TY - GEN A1 - Caliendo, Marco A1 - Schmidl, Ricarda T1 - Youth unemployment and active labor market policies in Europe T2 - Postprints der Universität Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe N2 - Since the economic crisis in 2008, European youth unemployment rates have been persistently high at around 20% on average. The majority of European countries spends significant resources each year on active labor market programs (ALMP) with the aim of improving the integration prospects of struggling youths. Among the most common programs used are training courses, job search assistance and monitoring, subsidized employment, and public work programs. For policy makers, it is of upmost importance to know which of these programs work and which are able to achieve the intended goals – may it be the integration into the first labor market or further education. Based on a detailed assessment of the particularities of the youth labor market situation, we discuss the pros and cons of different ALMP types. We then provide a comprehensive survey of the recent evidence on the effectiveness of these ALMP for youth in Europe, highlighting factors that seem to promote or impede their effectiveness in practice. Overall, the findings with respect to employment outcomes are only partly promising. While job search assistance (with and without monitoring) results in overwhelmingly positive effects, we find more mixed effects for training and wage subsidies, whereas the effects for public work programs are clearly negative. The evidence on the impact of ALMP on furthering education participation as well as employment quality is scarce, requiring additional research and allowing only limited conclusions so far. T3 - Zweitveröffentlichungen der Universität Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe - 125 KW - youth unemployment KW - active labor market policies KW - evaluation KW - training KW - job search Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-436950 SN - 1867-5808 IS - 125 ER - TY - JOUR A1 - Guiet, Amandine A1 - Unmüssig, Tobias A1 - Göbel, Caren A1 - Vainio, Ulla A1 - Wollgarten, Markus A1 - Driess, Matthias A1 - Schlaad, Helmut A1 - Polte, Jörg A1 - Fischer, Anna T1 - Yolk@Shell Nanoarchitectures with Bimetallic Nanocores - Synthesis and Electrocatalytic Applications JF - Earth & planetary science letters KW - AgAu alloy nanoparticles KW - tin-rich ITO KW - yolk@shell materials KW - nanoreactor KW - soft-templating KW - inverse micelles KW - polystyrene-block-poly(4-vinylpyridine) Y1 - 2016 U6 - https://doi.org/10.1021/acsami.6b06595 SN - 1944-8244 VL - 8 SP - 28019 EP - 28029 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Kleinpeter, Erich A1 - Koch, Andreas T1 - Y-aromaticity - existing: yes or no? An answer given on the magnetic criterion (TSNMRS) JF - Tetrahedron N2 - The spatial magnetic properties (Through Space NMR Shieldings - TSNMRS) of a number of Y-shaped structures possessing 4n+2 pi-electrons (i.a. the trimethylenemethane ions TMM2+, TMM2-, the guanidinium cation, substituted and hetero analogues) have been computed, visualized as Isochemical Shielding Surfaces (ICSS) of various size and direction, were examined subject to present Y-aromaticity and the results compared with energetic and geometric criteria obtained already. (C) 2016 Elsevier Ltd. All rights reserved. KW - Y-aromaticity KW - pi-Electron delocalization KW - Theoretical calculations KW - ICSS KW - TSNMRS Y1 - 2016 U6 - https://doi.org/10.1016/j.tet.2016.02.020 SN - 0040-4020 VL - 72 SP - 1675 EP - 1685 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Cioni, Maria-Rosa L. A1 - Bekki, Kenji A1 - Girardi, Leo A1 - de Grijs, Richard A1 - Irwin, Mike J. A1 - Ivanov, Valentin D. A1 - Marconi, Marcella A1 - Oliveira, Joana M. A1 - Piatti, Andres E. A1 - Ripepi, Vincenzo A1 - van Loon, Jacco Th. T1 - XVII. Proper motions of the Small Magellanic Cloud and the Milky Way globular cluster 47 Tucanae JF - Physical review : E, Statistical, nonlinear and soft matter physics N2 - Aims. In this study we use multi-epoch near-infrared observations from the VISTA survey of the Magellanic Cloud system (VMC) to measure the proper motions of different stellar populations in a tile of 1.5 deg2 in size in the direction of the Galactic globular cluster 47 Tuc. We obtain the proper motion of the cluster itself, of the Small Magellanic Cloud (SMC), and of the field Milky Way stars. Methods. Stars of the three main stellar components are selected according to their spatial distributions and their distributions in colour−magnitude diagrams. Their average coordinate displacement is computed from the difference between multiple Ks-band observations for stars as faint as Ks = 19 mag. Proper motions are derived from the slope of the best-fitting line among ten VMC epochs over a time baseline of ~1 yr. Background galaxies are used to calibrate the absolute astrometric reference frame. Results. The resulting absolute proper motion of 47 Tuc is (μαcos(δ), μδ) = (+7.26 ± 0.03, −1.25 ± 0.03) mas yr-1. This measurement refers to about 35 000 sources distributed between 10′ and 60′ from the cluster centre. For the SMC we obtain (μαcos(δ), μδ) = (+1.16 ± 0.07, −0.81 ± 0.07) mas yr-1 from about 5250 red clump and red giant branch stars. The absolute proper motion of the Milky Way population in the line of sight (l = 305.9, b = −44.9) of this VISTA tile is (μαcos(δ), μδ) = (+10.22 ± 0.14, −1.27 ± 0.12) mas yr-1 and has been calculated from about 4000 sources. Systematic uncertainties associated with the astrometric reference system are 0.18 mas yr-1. Thanks to the proper motion we detect 47 Tuc stars beyond its tidal radius. KW - proper motions KW - surveys KW - Magellanic Clouds KW - globular clusters: individual: 47 Tucanae Y1 - 2016 U6 - https://doi.org/10.1051/0004-6361/201527004 SN - 1432-0746 VL - 586 SP - 67 EP - 75 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Toala, Jesús Alberto A1 - Oskinova, Lidia M. A1 - Gonzalez-Galan, Ana A1 - Guerrero, Martín A. A1 - Ignace, R. A1 - Pohl, Martin T1 - X-RAY OBSERVATIONS OF BOW SHOCKS AROUND RUNAWAY O STARS. THE CASE OF zeta OPH AND BD+43 degrees 3654 JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - Non-thermal radiation has been predicted within bow shocks around runaway stars by recent theoretical works. We present X-ray observations toward the runaway stars zeta Oph by Chandra and Suzaku and of BD+43 degrees 3654 by XMM-Newton to search for the presence of non-thermal X-ray emission. We found no evidence of non-thermal emission spatially coincident with the bow shocks; nonetheless, diffuse emission was detected in the vicinity of zeta Oph. After a careful analysis of its spectral characteristics, we conclude that this emission has a thermal nature with a plasma temperature of T approximate to 2 x 10(6) K. The cometary shape of this emission seems to be in line with recent predictions of radiation-hydrodynamic models of runaway stars. The case of BD+43 degrees 3654 is puzzling, as non-thermal emission has been reported in a previous work for this source. KW - stars: individual (zeta Oph, BD+43 degrees 3654) KW - stars: winds, outflows Y1 - 2016 U6 - https://doi.org/10.3847/0004-637X/821/2/79 SN - 0004-637X SN - 1538-4357 VL - 821 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Oskinova, Lidia M. T1 - X-ray diagnostics of massive star winds JF - Advances in space research N2 - Nearly all types of massive stars with radiatively driven stellar winds are X-ray sources that can be observed by the presently operating powerful X-ray telescopes. In this review I briefly address recent advances in our understanding of stellar winds obtained from X-ray observations. X-rays may strongly influence the dynamics of weak winds of main sequence B-type stars. X-ray pulsations were detected in a beta Cep type variable giving evidence of tight photosphere-wind connections. The winds of OB dwarfs with subtypes later than O9V may be predominantly in a hot phase, and X-ray observations offer the best window for their studies. The X-ray properties of OB super giants are largely determined by the effects of radiative transfer in their clumped stellar winds. The recently suggested method to directly measure mass-loss rates of O stars by fitting the shapes of X-ray emission lines is considered but its validity cannot be confirmed. To obtain robust quantitative information on stellar wind parameters from X-ray spectroscopy, a multiwavelength analysis by means of stellar atmosphere models is required. Independent groups are now performing such analyses with encouraging results. Joint analyses of optical, UV, and X-ray spectra of OB supergiants yield consistent mass-loss rates. Depending on the adopted clumping parameters, the empirically derived mass-loss rates are a factor of a few smaller or comparable to those predicted by standard recipes (Vink et al., 2001). All sufficiently studied O stars display variable X-ray emission that might be related to corotating interaction regions in their winds. In the latest stages of stellar evolution, single red supergiants (RSG) and luminous blue variable (LBV) stars do not emit observable amounts of X-rays. On the other hand, nearly all types of Wolf-Rayet (WR) stars are X-ray sources. X-ray spectroscopy allows a sensitive probe of WR wind abundances and opacities. (C) 2016 COSPAR. Published by Elsevier Ltd. All rights reserved. KW - Blue stars KW - Stellar winds KW - X-ray emission spectra Y1 - 2016 U6 - https://doi.org/10.1016/j.asr.2016.06.030 SN - 0273-1177 SN - 1879-1948 VL - 58 SP - 739 EP - 760 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Kroll, Thomas A1 - Kern, Jan A1 - Kubin, Markus A1 - Ratner, Daniel A1 - Gul, Sheraz A1 - Fuller, Franklin D. A1 - Löchel, Heike A1 - Krzywinski, Jacek A1 - Lutman, Alberto A1 - Ding, Yuantao A1 - Dakovski, Georgi L. A1 - Moeller, Stefan A1 - Turner, Joshua J. A1 - Alonso-Mori, Roberto A1 - Nordlund, Dennis L. A1 - Rehanek, Jens A1 - Weniger, Christian A1 - Firsov, Alexander A1 - Brzhezinskaya, Maria A1 - Chatterjee, Ruchira A1 - Lassalle-Kaiser, Benedikt A1 - Sierra, Raymond G. A1 - Laksmono, Hartawan A1 - Hill, Ethan A1 - Borovik, Andrew S. A1 - Erko, Alexei A1 - Föhlisch, Alexander A1 - Mitzner, Rolf A1 - Yachandra, Vittal K. A1 - Yano, Junko A1 - Wernet, Philippe A1 - Bergmann, Uwe T1 - X-ray absorption spectroscopy using a self-seeded soft X-ray free-electron laser JF - Optics express : the international electronic journal of optics N2 - X-ray free electron lasers (XFELs) enable unprecedented new ways to study the electronic structure and dynamics of transition metal systems. L-edge absorption spectroscopy is a powerful technique for such studies and the feasibility of this method at XFELs for solutions and solids has been demonstrated. However, the required x-ray bandwidth is an order of magnitude narrower than that of self-amplified spontaneous emission (SASE), and additional monochromatization is needed. Here we compare L-edge x-ray absorption spectroscopy (XAS) of a prototypical transition metal system based on monochromatizing the SASE radiation of the linac coherent light source (LCLS) with a new technique based on self-seeding of LCLS. We demonstrate how L-edge XAS can be performed using the self-seeding scheme without the need of an additional beam line monochromator. We show how the spectral shape and pulse energy depend on the undulator setup and how this affects the x-ray spectroscopy measurements. (C) 2016 Optical Society of America Y1 - 2016 U6 - https://doi.org/10.1364/OE.24.022469 SN - 1094-4087 VL - 24 SP - 22469 EP - 22480 PB - Optical Society of America CY - Washington ER - TY - BOOK A1 - Ette, Ottmar T1 - Writing-between-worlds BT - transarea studies and the literatures-without-a-fixed-abode T3 - Mimesis ; 64 Y1 - 2016 SN - 978-3-11-046109-1 PB - de Gruyter CY - Berlin ER - TY - JOUR A1 - Marton, Klara A1 - Eichorn, Naomi A1 - Campanelli, Luca A1 - Zakarias, Lilla T1 - Working Memory and Interference Control in Children with Specific Language Impairment JF - Language and linguistics compass N2 - Language and communication disorders are often associated with deficits in working memory (WM) and interference control. WM studies involving children with specific language impairment (SLI) have traditionally been framed using either resource theories or decay accounts, particularly Baddeley's model. Although significant interference problems in children with SLI are apparent in error analysis data from WM and language tasks, interference theories and paradigms have not been widely used in the SLI literature. A primary goal of the present paper is to provide an overview of interference deficits in children with SLI. Review of the extant literature on interference control shows deficits in this population; however, the source and the nature of the deficit remain unclear. Thus, a second key aim in our review is to demonstrate the need for theoretically driven experimental paradigms in order to better understand individual variations associated with interference weaknesses in children with SLI. Y1 - 2016 U6 - https://doi.org/10.1111/lnc3.12189 SN - 1749-818X VL - 10 SP - 211 EP - 224 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Muschalla, Beate A1 - Linden, Michael A1 - Joebges, Michael T1 - Work-Anxiety and Sickness Absence After a Short Inpatient Cognitive Behavioral Group Intervention in Comparison to a Recreational Group Meeting JF - Journal of occupational and environmental medicine N2 - Objective: The aim of this study was to study the effects of a short-term cognitive behavior therapy on work-anxiety and sickness-absence in patients with work-anxiety. Methods: Three-hundred forty-five inpatients who suffered from cardiologic, neurological, or orthopedic problems and additionally work-anxiety were randomly assigned into two different group interventions. Patients got four sessions of a group intervention, which either focused on cognitive behavior-therapy anxiety-management (work-anxiety coping group, WAG) or unspecific recreational activities (RG). Results: No differences were found between WAG and RG for work-anxiety and subjective work ability. When looking at patients who were suffering only from work-anxiety, and no additional mental disorder, the duration of sickness absence until 6 months follow-up was shorter in the WAG (WAG: 11 weeks, RG: 16 weeks, P = 0.050). Conclusion: A shortterm WAG may help return to work in patients with work-anxieties, as long as there is no comorbid mental disorder. Y1 - 2016 U6 - https://doi.org/10.1097/JOM.0000000000000678 SN - 1076-2752 SN - 1536-5948 VL - 58 SP - 398 EP - 406 PB - American Institute of Physics CY - Philadelphia ER - TY - JOUR A1 - Shenar, Tomer A1 - Hainich, Rainer A1 - Todt, Helge Tobias A1 - Sander, Andreas Alexander Christoph A1 - Hamann, Wolf-Rainer A1 - Moffat, Anthony F. J. A1 - Eldridge, J. J. A1 - Pablo, H. A1 - Oskinova, Lidia M. A1 - Richardson, N. D. T1 - Wolf-Rayet stars in the Small Magellanic Cloud II. Analysis of the binaries JF - American mineralogist : an international journal of earth and planetary materials N2 - Context. Massive Wolf-Rayet (WR) stars are evolved massive stars (M-i greater than or similar to 20 M-circle dot) characterized by strong mass-loss. Hypothetically, they can form either as single stars or as mass donors in close binaries. About 40% of all known WR stars are confirmed binaries, raising the question as to the impact of binarity on the WR population. Studying WR binaries is crucial in this context, and furthermore enable one to reliably derive the elusive masses of their components, making them indispensable for the study of massive stars. Aims. By performing a spectral analysis of all multiple WR systems in the Small Magellanic Cloud (SMC), we obtain the full set of stellar parameters for each individual component. Mass-luminosity relations are tested, and the importance of the binary evolution channel is assessed. Methods. The spectral analysis is performed with the PotsdamWolf-Rayet (PoWR) model atmosphere code by superimposing model spectra that correspond to each component. Evolutionary channels are constrained using the Binary Population and Spectral Synthesis (BPASS) evolution tool. Results. Significant hydrogen mass fractions (0.1 < X-H < 0.4) are detected in all WN components. A comparison with mass-luminosity relations and evolutionary tracks implies that the majority of the WR stars in our sample are not chemically homogeneous. The WR component in the binary AB6 is found to be very luminous (log L approximate to 6.3 [L-circle dot]) given its orbital mass (approximate to 10 M-circle dot), presumably because of observational contamination by a third component. Evolutionary paths derived for our objects suggest that Roche lobe overflow had occurred in most systems, affecting their evolution. However, the implied initial masses (greater than or similar to 60 M-circle dot) are large enough for the primaries to have entered the WR phase, regardless of binary interaction. Conclusions. Together with the results for the putatively single SMC WR stars, our study suggests that the binary evolution channel does not dominate the formation of WR stars at SMC metallicity. KW - stars: massive KW - stars: Wolf-Rayet KW - stars: evolution KW - binaries: close KW - binaries: symbiotic KW - Magellanic Clouds Y1 - 2016 U6 - https://doi.org/10.1051/0004-6361/201527916 SN - 1432-0746 VL - 591 PB - EDP Sciences CY - Les Ulis ER - TY - THES A1 - Wittenberg, Eva T1 - With Light Verb Constructions from Syntax to Concepts T1 - Mit Funktionsverbgefügen von der Syntax zur konzeptuellen Struktur N2 - This dissertation uses a common grammatical phenomenon, light verb constructions (LVCs) in English and German, to investigate how syntax-semantics mapping defaults influence the relationships between language processing, representation and conceptualization. LVCs are analyzed as a phenomenon of mismatch in the argument structure. The processing implication of this mismatch are experimentally investigated, using ERPs and a dual task. Data from these experiments point to an increase in working memory. Representational questions are investigated using structural priming. Data from this study suggest that while the syntax of LVCs is not different from other structures’, the semantics and mapping are represented differently. This hypothesis is tested with a new categorization paradigm, which reveals that the conceptual structure that LVC evoke differ in interesting, and predictable, ways from non-mismatching structures’. N2 - Diese Dissertation untersucht mittels psycho- und neurolinguistischer Experimente, wie deutsche und englische Funktionsverbgefüge (’light verb constructions’) mental repräsentiert und verarbeitet werden. Funktionsverbgefüge sind Konstruktionen wie einen Kuss geben, in denen die Semantik überwiegend durch die Nominalisierung Kuss geliefert wird, während das Funktionsverb geben lediglich den syntaktischen Rahmen und grammatische Marker, aber nur wenige Bedeutungsaspekte beiträgt. T3 - Potsdam Cognitive Science Series - 7 KW - light verb constructions KW - syntax KW - semantics KW - event-related potential KW - priming KW - Syntax KW - Semantik KW - Sprachverarbeitung KW - Funktionsverbgefüge KW - Priming Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-82361 SN - 978-3-86956-329-9 SN - 2190-4545 SN - 2190-4553 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Pinyou, Piyanut A1 - Ruff, Adrian A1 - Poeller, Sascha A1 - Alsaoub, Sabine A1 - Leimkühler, Silke A1 - Wollenberger, Ursula A1 - Schuhmann, Wolfgang T1 - Wiring of the aldehyde oxidoreductase PaoABC to electrode surfaces via entrapment in low potential phenothiazine-modified redox polymers JF - Bioelectrochemistry : an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry ; official journal of the Bioelectrochemical Society N2 - Phenothiazine-modified redox hydrogels were synthesized and used for the wiring of the aldehyde oxidoreductase PaoABC to electrode surfaces. The effects of the pH value and electrode surface modification on the biocatalytic activity of the layers were studied in the presence of vanillin as the substrate. The enzyme electrodes were successfully employed as bioanodes in vanillin/O-2 biofuel cells in combination with a high potential bilirubin oxidase biocathode. Open circuit voltages of around 700 mV could be obtained in a two compartment biofuel cell setup. Moreover, the use of a rather hydrophobic polymer with a high degree of crosslinking sites ensures the formation of stable polymer/enzyme films which were successfully used as bioanode in membrane-less biofuel cells. (C) 2015 Elsevier B.V. All rights reserved. KW - Aldehyde oxidoreductase KW - Enzyme electrode KW - Redox polymer KW - Phenothiazine KW - Biosensor KW - Biofuel cell Y1 - 2016 U6 - https://doi.org/10.1016/j.bioelechem.2015.12.005 SN - 1567-5394 SN - 1878-562X VL - 109 SP - 24 EP - 30 PB - Elsevier CY - Lausanne ER - TY - JOUR A1 - Borck, Rainald T1 - Will skyscrapers save the planet? Building height limits and urban greenhouse gas emissions JF - Regional science and urban economics N2 - This paper studies the effectiveness of building height limits as a policy to limit greenhouse gas (GHG) emissions. It shows that building height limits lead to urban sprawl and higher emissions from commuting. On the other hand, aggregate housing consumption may decrease, which reduces emissions from residential energy use. A numerical model is used to evaluate whether total GHG emissions may be lower under building height restrictions. Welfare is not concave in the strictness of building height limits, so either no limit or a very strict one (depending on the strength of the externality) might maximize welfare. The paper discusses several extensions, such as congestion, endogenous transport mode choice, migration, and urban heat island effect. (C) 2016 Elsevier B.V. All rights reserved KW - Greenhouse gas emissions KW - City structure KW - Building height limits Y1 - 2016 U6 - https://doi.org/10.1016/j.regsciurbeco.2016.01.004 SN - 0166-0462 SN - 1879-2308 VL - 58 SP - 13 EP - 25 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Estrany, Joan A1 - López-Tarazón, José Andrés A1 - Smith, Hugh G. T1 - WILDFIRE EFFECTS ON SUSPENDED SEDIMENT DELIVERY QUANTIFIED USING FALLOUT RADIONUCLIDE TRACERS IN A MEDITERRANEAN CATCHMENT JF - Physical review : E, Statistical, nonlinear and soft matter physics N2 - Over short and long timescales, wildfires can be an important cause of hydrological and geomorphological change. Mediterranean rivers are part of a fire-prone and high-energy environment in which the timing of major storms in relation to fire influences the impact on fluvial systems; accordingly, the identification of major sources, stores and fluxes of sediments is essential for providing more effective post-fire management strategies. In this study, caesium-137 and excess lead-210 were used as tracers to quantify the proportional contributions of fine sediment from hillslope surface and channel bank sources to suspended sediment and channel bed deposits before the impact of a forest wildfire in Na Borges, a Mediterranean groundwater-dominated river. It also compared burnt and unburnt spatial sources of sediment within a single catchment and the extent to which burnt material was transported downstream. The study focused on two small and steep sub-catchments, where just one of the catchments was partially affected by a wildfire. The pre-fire dynamics indicated that surface soils were the main sediment source in these ephemeral creeks. Post-fire sediment dynamics were characterised by a single flood event with a short recurrence interval (i.e. return period ca. <1 year). Sediment generated from the burnt area contributed 12% on average to bed-stored sediments within the burnt catchment, which reduced downstream to 5% along the main channel of the Na Borges River. The findings demonstrate the potential for using fallout radionuclide tracers to understand the wider impacts of wildfires on fluvial environments located outside of the burn area. Copyright (C) 2015 John Wiley & Sons, Ltd. KW - wildfire KW - sediment delivery processes KW - sediment source fingerprinting KW - fallout radionuclides KW - Mediterranean fluvial systems Y1 - 2016 U6 - https://doi.org/10.1002/ldr.2462 SN - 1085-3278 SN - 1099-145X VL - 27 SP - 1501 EP - 1512 PB - Wiley CY - Hoboken ER - TY - GEN A1 - Meiling, Till Thomas A1 - Cywiński, Piotr J. A1 - Bald, Ilko T1 - White carbon: Fluorescent carbon nanoparticles with tunable quantum yield in a reproducible green synthesis N2 - In this study, a new reliable, economic, and environmentally-friendly one-step synthesis is established to obtain carbon nanodots (CNDs) with well-defined and reproducible photoluminescence (PL) properties via the microwave-assisted hydrothermal treatment of starch and Tris-acetate-EDTA (TAE) buffer as carbon sources. Three kinds of CNDs are prepared using different sets of above mentioned starting materials. The as-synthesized CNDs: C-CND (starch only), N-CND 1 (starch in TAE) and N-CND 2 (TAE only) exhibit highly homogenous PL and are ready to use without need for further purification. The CNDs are stable over a long period of time (>1 year) either in solution or as freeze-dried powder. Depending on starting material, CNDs with PL quantum yield (PLQY) ranging from less than 1% up to 28% are obtained. The influence of the precursor concentration, reaction time and type of additives on the optical properties (UV-Vis absorption, PL emission spectrum and PLQY) is carefully investigated, providing insight into the chemical processes that occur during CND formation. Remarkably, upon freeze-drying the initially brown CND-solution turns into a non-fluorescent white/slightly brown powder which recovers PL in aqueous solution and can potentially be applied as fluorescent marker in bio-imaging, as a reduction agent or as a photocatalyst. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 264 KW - Fluorescence spectroscopy KW - Nanoparticles KW - Synthesis and processing Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-97087 ER - TY - JOUR A1 - Meiling, Till T. A1 - Cywinski, Piotr J. A1 - Bald, Ilko T1 - White carbon: Fluorescent carbon nanoparticles with tunable quantum yield in a reproducible green synthesis JF - Scientific reports N2 - In this study, a new reliable, economic, and environmentally-friendly one-step synthesis is established to obtain carbon nanodots (CNDs) with well-defined and reproducible photoluminescence (PL) properties via the microwave-assisted hydrothermal treatment of starch and Tris-acetate-EDTA (TAE) buffer as carbon sources. Three kinds of CNDs are prepared using different sets of above mentioned starting materials. The as-synthesized CNDs: C-CND (starch only), N-CND 1 (starch in TAE) and N-CND 2 (TAE only) exhibit highly homogenous PL and are ready to use without need for further purification. The CNDs are stable over a long period of time (> 1 year) either in solution or as freeze-dried powder. Depending on starting material, CNDs with PL quantum yield (PLQY) ranging from less than 1% up to 28% are obtained. The influence of the precursor concentration, reaction time and type of additives on the optical properties (UV-Vis absorption, PL emission spectrum and PLQY) is carefully investigated, providing insight into the chemical processes that occur during CND formation. Remarkably, upon freeze-drying the initially brown CND-solution turns into a non-fluorescent white/slightly brown powder which recovers PL in aqueous solution and can potentially be applied as fluorescent marker in bio-imaging, as a reduction agent or as a photocatalyst. Y1 - 2016 U6 - https://doi.org/10.1038/srep28557 SN - 2045-2322 VL - 6 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Meiling, Till Thomas A1 - Cywiński, Piotr J. A1 - Bald, Ilko T1 - White carbon: Fluorescent carbon nanoparticles with tunable quantum yield in a reproducible green synthesis JF - Scientific reports N2 - In this study, a new reliable, economic, and environmentally-friendly one-step synthesis is established to obtain carbon nanodots (CNDs) with well-defined and reproducible photoluminescence (PL) properties via the microwave-assisted hydrothermal treatment of starch and Tris-acetate-EDTA (TAE) buffer as carbon sources. Three kinds of CNDs are prepared using different sets of above mentioned starting materials. The as-synthesized CNDs: C-CND (starch only), N-CND 1 (starch in TAE) and N-CND 2 (TAE only) exhibit highly homogenous PL and are ready to use without need for further purification. The CNDs are stable over a long period of time (>1 year) either in solution or as freeze-dried powder. Depending on starting material, CNDs with PL quantum yield (PLQY) ranging from less than 1% up to 28% are obtained. The influence of the precursor concentration, reaction time and type of additives on the optical properties (UV-Vis absorption, PL emission spectrum and PLQY) is carefully investigated, providing insight into the chemical processes that occur during CND formation. Remarkably, upon freeze-drying the initially brown CND-solution turns into a non-fluorescent white/slightly brown powder which recovers PL in aqueous solution and can potentially be applied as fluorescent marker in bio-imaging, as a reduction agent or as a photocatalyst. KW - Fluorescence spectroscopy KW - Nanoparticles KW - Synthesis and processing Y1 - 2016 U6 - https://doi.org/10.1038/srep28557 VL - 6 PB - Nature Publishing Group CY - London ER - TY - JOUR A1 - Schneider, A. -K. A1 - van Schaik, L. A1 - Zangerle, A. A1 - Eccard, Jana A1 - Schroeder, B. T1 - Which abiotic filters shape earthworm distribution patterns at the catchment scale? JF - European journal of soil science N2 - Earthworms affect various soil ecosystem processes in their role as ecosystem engineers. The spatial distribution of earthworms determines the spatial distribution of their functional effects. In particular, earthworm-induced macropore networks may act as preferential flow pathways. In this research we aimed to determine earthworm distributions at the catchment scale with species distribution models (SDMs). We used land-use types, temporally invariant topography-related variables and plot-scale soil characteristics such as pH and organic matter content. We used data from spring 2013 to estimate probability distributions of the occurrence of ten earthworm species. To assess the robustness of these models, we tested temporal transferability by evaluating the accuracy of predictions from the models derived for the spring data with the predictions from data of two other field surveys in autumn 2012 and 2013. In addition, we compared the performance of SDMs based (i) on temporally varying plot-scale predictor variables with (ii) those based on temporally invariant catchment-scale predictors. Models based on catchment-scale predictors, especially land use and slope, experience a small loss of predictive performance only compared with plot-scale SDMs but have greater temporal transferability. Earthworm distribution maps derived from this kind of SDM are a prerequisite for understanding the spatial distribution patterns of functional effects related to earthworms. Y1 - 2016 U6 - https://doi.org/10.1111/ejss.12346 SN - 1351-0754 SN - 1365-2389 VL - 67 SP - 431 EP - 442 PB - Wiley-Blackwell CY - Hoboken ER - TY - GEN A1 - Nicenboim, Bruno A1 - Logacev, Pavel A1 - Gattei, Carolina A1 - Vasishth, Shravan T1 - When High-Capacity Readers Slow Down and Low-Capacity Readers Speed Up BT - Working Memory and Locality Effects N2 - We examined the effects of argument-head distance in SVO and SOV languages (Spanish and German), while taking into account readers' working memory capacity and controlling for expectation (Levy, 2008) and other factors. We predicted only locality effects, that is, a slowdown produced by increased dependency distance (Gibson, 2000; Lewis and Vasishth, 2005). Furthermore, we expected stronger locality effects for readers with low working memory capacity. Contrary to our predictions, low-capacity readers showed faster reading with increased distance, while high-capacity readers showed locality effects. We suggest that while the locality effects are compatible with memory-based explanations, the speedup of low-capacity readers can be explained by an increased probability of retrieval failure. We present a computational model based on ACT-R built under the previous assumptions, which is able to give a qualitative account for the present data and can be tested in future research. Our results suggest that in some cases, interpreting longer RTs as indexing increased processing difficulty and shorter RTs as facilitation may be too simplistic: The same increase in processing difficulty may lead to slowdowns in high-capacity readers and speedups in low-capacity ones. Ignoring individual level capacity differences when investigating locality effects may lead to misleading conclusions. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 288 KW - locality KW - working memory capacity KW - individual differences KW - Spanish KW - German KW - ACT-R Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-90663 SP - 1 EP - 24 ER - TY - JOUR A1 - Nicenboim, Bruno A1 - Logacev, Pavel A1 - Gattei, Carolina A1 - Vasishth, Shravan T1 - When High-Capacity Readers Slow Down and Low-Capacity Readers Speed Up BT - Working Memory and Locality Effects JF - Frontiers in psychology N2 - We examined the effects of argument-head distance in SVO and SOV languages (Spanish and German), while taking into account readers' working memory capacity and controlling for expectation (Levy, 2008) and other factors. We predicted only locality effects, that is, a slowdown produced by increased dependency distance (Gibson, 2000; Lewis and Vasishth, 2005). Furthermore, we expected stronger locality effects for readers with low working memory capacity. Contrary to our predictions, low-capacity readers showed faster reading with increased distance, while high-capacity readers showed locality effects. We suggest that while the locality effects are compatible with memory-based explanations, the speedup of low-capacity readers can be explained by an increased probability of retrieval failure. We present a computational model based on ACT-R built under the previous assumptions, which is able to give a qualitative account for the present data and can be tested in future research. Our results suggest that in some cases, interpreting longer RTs as indexing increased processing difficulty and shorter RTs as facilitation may be too simplistic: The same increase in processing difficulty may lead to slowdowns in high-capacity readers and speedups in low-capacity ones. Ignoring individual level capacity differences when investigating locality effects may lead to misleading conclusions. KW - locality KW - working memory capacity KW - individual differences KW - Spanish KW - German KW - ACT-R Y1 - 2016 U6 - https://doi.org/10.3389/fpsyg.2016.00280 SN - 1664-1078 VL - 7 SP - 1 EP - 24 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Sievers, Steven A1 - Rawel, Harshadrai Manilal A1 - Ringel, Karl Peter A1 - Niggemann, Bodo A1 - Beyer, Kirsten T1 - Wheat protein recognition pattern in tolerant and allergic children JF - Pediatric Allergy and Immunology N2 - BackgroundWheat is one of the most common food allergens in early childhood. In contrast to other food allergies, wheat-specific IgE correlates badly with clinical symptoms and relevant components have been identified mostly for wheat-depended exercise-induced anaphylaxis. Moreover, a high percentage of patients present with immediate type symptoms but wheat-specific IgE cannot be detected with commercial available systems. ObjectiveWe addressed the question whether the IgE recognition pattern between wheat allergic (WA) and clinically tolerant (WT) children differs in order to identify individual proteins useful for component-resolved diagnostics. MethodsSera of 106 children with suspected wheat allergy, of whom 44 children had clinical relevant wheat allergy and 62 were tolerant upon oral food challenge, were analyzed for wheat-specific IgE using the ImmunoCap system as well as immunoblots against water and salt soluble, and water-insoluble protein fractions. 40 randomly selected sera were analyzed for specific IgE to 5-gliadin. ResultsSixty-three percent of the WT and 86% of the WA children were sensitized to wheat with >0.35 kU(A)/l in ImmunoCAP analysis. We could confirm the role of -, ss-, -, and -gliadins, and LMW glutenin subunits as major allergens and found also IgE binding to a broad spectrum of water- and salt-soluble protein bands. It is of great importance that wheat allergic and tolerant patients showed IgE binding to the same protein bands. WT and WA did not significantly differ in levels of 5-gliadin-specific IgE. Conclusions & Clinical RelevanceChildren with challenge proven clinical relevant food allergy and tolerant ones had a similar spectrum of IgE binding to the same protein bands. These findings imply that component-resolved diagnostics might not be helpful in the diagnostic work-up of wheat allergy. KW - wheat KW - IgE KW - 5-gliadin KW - protein pattern KW - immunoblot Y1 - 2016 U6 - https://doi.org/10.1111/pai.12502 SN - 0905-6157 SN - 1399-3038 VL - 27 SP - 147 EP - 155 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Al-Ani, Ayad T1 - What is the Role for Civil Society, State Institutions, Entrepreneurs and Non State Actors After the Arab Spring? JF - Arabian Journal of Business and Management Review Y1 - 2016 U6 - https://doi.org/10.4172/2223-5833.1000241 SN - 2223-5833 VL - 6 IS - 4 ER - TY - JOUR A1 - Khadem, S. M. J. A1 - Hille, Carsten A1 - Löhmannsröben, Hans-Gerd A1 - Sokolov, Igor M. T1 - What information is contained in the fluorescence correlation spectroscopy curves, and where JF - Physical review : E, Statistical, nonlinear and soft matter physics Y1 - 2016 U6 - https://doi.org/10.1103/PhysRevE.94.022407 SN - 2470-0045 SN - 2470-0053 VL - 94 PB - American Physical Society CY - College Park ER - TY - JOUR A1 - Lehmann, Andreas A1 - Scheffler, Christiane T1 - What does the mean menarcheal age mean?An analysis of temporal pattern in variability in a historical swiss population from the 19th and 20th centuries JF - American journal of human biology : the official journal of the Human Biology Council N2 - ObjectivesAge at menarche is one of the most important factors when observing growth and development. The aim of this study was to assess the temporal pattern in variability of menarcheal age for a historic Swiss population from the 19th and 20th centuries. ResultsMean menarcheal age declined from 17.34 years (n=358) around 1830 to 13.80 years (n=141) around 1950. Within-cohort variance decreased from 7.5 to 2.1 year(2). Skewness was negatively correlated with birth year (r=-0.58). ConclusionThis study provided evidence for a secular trend in various statistical parameters for age at menarche since the 19th century. Furthermore, the results of the analysis of temporal pattern in variability revealed that the secular trend in menarcheal age happened in two phases. Am. J. Hum. Biol. 28:705-713, 2016. (c) 2016 Wiley Periodicals, Inc. Y1 - 2016 U6 - https://doi.org/10.1002/ajhb.22854 SN - 1042-0533 SN - 1520-6300 VL - 28 SP - 705 EP - 713 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Hiltl, Stephanie A1 - Böker, Alexander T1 - Wetting Phenomena on (Gradient) Wrinkle Substrates JF - Langmuir N2 - We characterize the wetting behavior of nano structured wrinkle and gradient wrinkle substrates. Different contact angles on both sides of a water droplet after deposition on a gradient sample induce the self-propelled motion of the liquid toward smaller wrinkle dimensions. The droplet motion is self-limited by the contact angles balancing out. Because of the correlation between droplet motion and contact angles, we investigate the wetting behavior of wrinkle substrates with constant dimensions (wavelengths of 400-1200 nm). Contact angles of water droplets on those substrates increase with increasing dimensions of the underlying substrate. The results are independent of the two measurement directions, parallel and perpendicular to the longitudinal axis of the nanostructure. The presented findings may be considered for designing microfluidic or related devices and initiate ideas for the development of further wrinkle applications. Y1 - 2016 U6 - https://doi.org/10.1021/acs.langmuir.6b02364 SN - 0743-7463 VL - 32 SP - 8882 EP - 8888 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Jendrzyca, Anna A1 - Warschburger, Petra T1 - Weight stigma and eating behaviours in elementary school children: A prospective population-based study JF - Appetite : multidisciplinary research on eating and drinking N2 - The relevance of weight stigma as an important factor in disordered eating has been supported by research. However, because most of the studies were cross-sectional and focussed on older children, the causal relationships could not be fully determined in childhood. The current study explores the role of weight stigma in body dissatisfaction and eating behaviours. The sample consisted of 773 girls and 713 boys, aged 6–11 years, who completed surveys assessing weight stigma experiences, body dissatisfaction and eating behaviours at two points of measurement, approximately one year apart. The children's external and disordered eating was rated via parental questionnaires. As expected, the pattern of the associations between weight status, weight stigma, body dissatisfaction and eating behaviours differed by gender. Experience of weight stigma in girls led to external and restrained eating one year later, whereas in boys no such association was observed. Body dissatisfaction mediated the association between weight stigma and restrained eating behaviours in girls, whereas in boys, body dissatisfaction directly influenced restrained eating behaviours. However, in both girls and boys weight status predicted body dissatisfaction and disordered eating, while weight stigma did not have a direct effect on disordered eating. Results suggest that interventions involving weight stigma should be a part of eating disorder prevention programmes, and gender-specific pathways should be considered. KW - Weight stigma KW - Disordered eating behaviours KW - Body dissatisfaction KW - Childhood KW - Prospective study Y1 - 2016 U6 - https://doi.org/10.1016/j.appet.2016.02.005 SN - 0195-6663 SN - 1095-8304 VL - 102 SP - 51 EP - 59 PB - Elsevier CY - London ER - TY - JOUR A1 - Ullrich, Andre A1 - Vladova, Gergana T1 - Weighing the Pros and Cons of Engaging in Open Innovation JF - Technology Innovation Management Review N2 - The positive aspects of open innovation projects are widely discussed in innovation management research and practice by means of case studies and best practices. However, enterprises, particularly small and medium-sized enterprises (SMEs) also face miscellaneous challenges in open innovation practice, leading to uncertainty and even renunciation of open innovation project participation. Thus, it is essential for SMEs to find the right balance between possible positive effects and negative consequences - the latter being the less studied "dark sides" of open innovation. However, appropriate methods of finding this balance are still lacking. In this article, we discuss the assessment of open innovation project participation by presenting a weighing and decision process framework as a conceivable solution approach. The framework includes an internal, external, and integrated analysis as well as a recommendation and decision phase. Piece by piece, we investigate the current situation and the innovation goals of the enterprise as an initial point for a decision for or against engaging in open innovation. Furthermore, we discuss the development of a software tool that automatically applies this framework and allows self-assessment by SMEs. KW - open innovation KW - open innovation participation KW - self-assessment tool KW - risks KW - benefits KW - entrepreneurship KW - SMEs Y1 - 2016 SN - 1927-0321 VL - 8 SP - 34 EP - 40 PB - Carleton University Graphic Services CY - Ottawa ER - TY - JOUR A1 - Menne, Ulrich T1 - Weakly Differentiable Functions on Varifolds JF - Indiana University mathematics journal N2 - The present paper is intended to provide the basis for the study of weakly differentiable functions on rectifiable varifolds with locally bounded first variation. The concept proposed here is defined by means of integration-by-parts identities for certain compositions with smooth functions. In this class, the idea of zero boundary values is realised using the relative perimeter of superlevel sets. Results include a variety of Sobolev Poincare-type embeddings, embeddings into spaces of continuous and sometimes Holder-continuous functions, and point wise differentiability results both of approximate and integral type as well as coarea formulae. As a prerequisite for this study, decomposition properties of such varifolds and a relative isoperimetric inequality are established. Both involve a concept of distributional boundary of a set introduced for this purpose. As applications, the finiteness of the geodesic distance associated with varifolds with suitable summability of the mean curvature and a characterisation of curvature varifolds are obtained. KW - Rectifiable varifold KW - (generalised) wealdy differentiable function KW - distributional boundary KW - decomposition KW - relative isoperimetric inequality KW - Sobolev Poincare inequality KW - approximate differentiability KW - coarea formula KW - geodesic distance KW - curvature varifold Y1 - 2016 U6 - https://doi.org/10.1512/iumj.2016.65.5829 SN - 0022-2518 SN - 1943-5258 VL - 65 SP - 977 EP - 1088 PB - Indiana University, Department of Mathematics CY - Bloomington ER - TY - JOUR A1 - Mehner, T. A1 - Attermeyer, Katrin A1 - Brauns, Mario A1 - Brothers, Soren M. A1 - Diekmann, J. A1 - Gaedke, Ursula A1 - Grossart, Hans-Peter A1 - Koehler, J. A1 - Lischke, Betty A1 - Meyer, N. A1 - Scharnweber, Inga Kristin A1 - Syvaranta, J. A1 - Vanni, M. J. A1 - Hilt, S. T1 - Weak Response of Animal Allochthony and Production to Enhanced Supply of Terrestrial Leaf Litter in Nutrient-Rich Lakes JF - Ecosystems N2 - Ecosystems are generally linked via fluxes of nutrients and energy across their boundaries. For example, freshwater ecosystems in temperate regions may receive significant inputs of terrestrially derived carbon via autumnal leaf litter. This terrestrial particulate organic carbon (POC) is hypothesized to subsidize animal production in lakes, but direct evidence is still lacking. We divided two small eutrophic lakes each into two sections and added isotopically distinct maize litter to the treatment sections to simulate increased terrestrial POC inputs via leaf litter in autumn. We quantified the reliance of aquatic consumers on terrestrial resources (allochthony) in the year subsequent to POC additions by applying mixing models of stable isotopes. We also estimated lake-wide carbon (C) balances to calculate the C flow to the production of the major aquatic consumer groups: benthic macroinvertebrates, crustacean zooplankton, and fish. The sum of secondary production of crustaceans and benthic macroinvertebrates supported by terrestrial POC was higher in the treatment sections of both lakes. In contrast, total secondary and tertiary production (supported by both autochthonous and allochthonous C) was higher in the reference than in the treatment sections of both lakes. Average aquatic consumer allochthony per lake section was 27-40%, although terrestrial POC contributed less than about 10% to total organic C supply to the lakes. The production of aquatic consumers incorporated less than 5% of the total organic C supply in both lakes, indicating a low ecological efficiency. We suggest that the consumption of terrestrial POC by aquatic consumers facilitates a strong coupling with the terrestrial environment. However, the high autochthonous production and the large pool of autochthonous detritus in these nutrient-rich lakes make terrestrial POC quantitatively unimportant for the C flows within food webs. KW - stable isotopes KW - terrestrial subsidy KW - carbon budget KW - ecological efficiency KW - benthic food web KW - pelagic food web Y1 - 2016 U6 - https://doi.org/10.1007/s10021-015-9933-2 SN - 1432-9840 SN - 1435-0629 VL - 19 SP - 311 EP - 325 PB - Springer CY - New York ER - TY - JOUR A1 - Schmidt, Burkhard A1 - Lorenz, Ulf T1 - WavePacket BT - a Matlab package for numerical quantum dynamics. I: Closed quantum systems and discrete variable representations JF - Computer physics communications : an international journal devoted to computational physics and computer programs in physics N2 - WavePacket is an open-source program package for the numerical simulation of quantum-mechanical dynamics. It can be used to solve time-independent or time-dependent linear Schrödinger and Liouville–von Neumann-equations in one or more dimensions. Also coupled equations can be treated, which allows to simulate molecular quantum dynamics beyond the Born–Oppenheimer approximation. Optionally accounting for the interaction with external electric fields within the semiclassical dipole approximation, WavePacket can be used to simulate experiments involving tailored light pulses in photo-induced physics or chemistry. The graphical capabilities allow visualization of quantum dynamics ‘on the fly’, including Wigner phase space representations. Being easy to use and highly versatile, WavePacket is well suited for the teaching of quantum mechanics as well as for research projects in atomic, molecular and optical physics or in physical or theoretical chemistry. The present Part I deals with the description of closed quantum systems in terms of Schrödinger equations. The emphasis is on discrete variable representations for spatial discretization as well as various techniques for temporal discretization. The upcoming Part II will focus on open quantum systems and dimension reduction; it also describes the codes for optimal control of quantum dynamics. The present work introduces the MATLAB version of WavePacket 5.2.1 which is hosted at the Sourceforge platform, where extensive Wiki-documentation as well as worked-out demonstration examples can be found. KW - Schrodinger equation KW - Quantum dynamics KW - Numerical propagation KW - Bound states KW - Discrete variable representation KW - Non-adiabatic transitions Y1 - 0207 U6 - https://doi.org/10.1016/j.cpc.2016.12.007 SN - 0010-4655 SN - 1879-2944 VL - 213 SP - 223 EP - 234 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Agarwal, Ankit A1 - Maheswaran, Rathinasamy A1 - Kurths, Jürgen A1 - Khosa, R. T1 - Wavelet Spectrum and Self-Organizing Maps-Based Approach for Hydrologic Regionalization -a Case Study in the Western United States JF - Water Resources Management N2 - Hydrologic regionalization deals with the investigation of homogeneity in watersheds and provides a classification of watersheds for regional analysis. The classification thus obtained can be used as a basis for mapping data from gauged to ungauged sites and can improve extreme event prediction. This paper proposes a wavelet power spectrum (WPS) coupled with the self-organizing map method for clustering hydrologic catchments. The application of this technique is implemented for gauged catchments. As a test case study, monthly streamflow records observed at 117 selected catchments throughout the western United States from 1951 through 2002. Further, based on WPS of each station, catchments are classified into homogeneous clusters, which provides a representative WPS pattern for the streamflow stations in each cluster. KW - Wavelet power spectrum KW - Regionalization KW - Ungauged catchments KW - K-means technique KW - Self-organizing map Y1 - 2016 U6 - https://doi.org/10.1007/s11269-016-1428-1 SN - 0920-4741 SN - 1573-1650 VL - 30 SP - 4399 EP - 4413 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Shprits, Yuri A1 - Drozdov, Alexander A1 - Spasojevic, Maria A1 - Kellerman, Adam C. A1 - Usanova, Maria E. A1 - Engebretson, Mark J. A1 - Agapitov, Oleksiy V. A1 - Zhelavskaya, Irina A1 - Raita, Tero J. A1 - Spence, Harlan E. A1 - Baker, Daniel N. A1 - Zhu, Hui A1 - Aseev, Nikita T1 - Wave-induced loss of ultra-relativistic electrons in the Van Allen radiation belts JF - Nature Communications Y1 - 2016 U6 - https://doi.org/10.1038/ncomms12883 SN - 2041-1723 VL - 7 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Taubert, Andreas A1 - Balischewski, Christian A1 - Hentrich, Doreen A1 - Elschner, Thomas A1 - Eidner, Sascha A1 - Günter, Christina A1 - Behrens, Karsten A1 - Heinze, Thomas T1 - Water-Soluble Cellulose Derivatives Are Sustainable Additives for Biomimetic Calcium Phosphate Mineralization JF - Inorganics : open access journal N2 - The effect of cellulose-based polyelectrolytes on biomimetic calcium phosphate mineralization is described. Three cellulose derivatives, a polyanion, a polycation, and a polyzwitterion were used as additives. Scanning electron microscopy, X-ray diffraction, IR and Raman spectroscopy show that, depending on the composition of the starting solution, hydroxyapatite or brushite precipitates form. Infrared and Raman spectroscopy also show that significant amounts of nitrate ions are incorporated in the precipitates. Energy dispersive X-ray spectroscopy shows that the Ca/P ratio varies throughout the samples and resembles that of other bioinspired calcium phosphate hybrid materials. Elemental analysis shows that the carbon (i.e., polymer) contents reach 10% in some samples, clearly illustrating the formation of a true hybrid material. Overall, the data indicate that a higher polymer concentration in the reaction mixture favors the formation of polymer-enriched materials, while lower polymer concentrations or high precursor concentrations favor the formation of products that are closely related to the control samples precipitated in the absence of polymer. The results thus highlight the potential of (water-soluble) cellulose derivatives for the synthesis and design of bioinspired and bio-based hybrid materials. KW - cellulose KW - polyamine KW - polyammonium salt KW - polycarboxylate KW - polyzwitterion KW - calcium phosphate KW - biomineralization KW - brushite KW - hydroyxapatite KW - biomaterial Y1 - 2016 U6 - https://doi.org/10.3390/inorganics4040033 SN - 2304-6740 VL - 4 PB - MDPI CY - Basel ER - TY - THES A1 - Janetschek, Hannah T1 - Water development programs in India T1 - Entwicklungszusammenarbeit im Wassersektor Indiens BT - governance processes and effectiveness BT - Governanceprozesse und Effektivität N2 - In the past decades, development cooperation (DC) led by conventional bi- and multilateral donors has been joined by a large number of small, private or public-private donors. This pluralism of actors raises questions as to whether or not these new donors are able to implement projects more or less effectively than their conventional counterparts. In contrast to their predecessors, the new donors have committed themselves to be more pragmatic, innovative and flexible in their development cooperation measures. However, they are also criticized for weakening the function of local civil society and have the reputation of being an intransparent and often controversial alternative to public services. With additional financial resources and their new approach to development, the new donors have been described in the literature as playing a controversial role in transforming development cooperation. This dissertation compares the effectiveness of initiatives by new and conventional donors with regard to the provision of public goods and services to the poor in the water and sanitation sector in India. India is an emerging country but it is experiencing high poverty rates and poor water supply in predominantly rural areas. It lends itself for analyzing this research theme as it is currently being confronted by a large number of actors and approaches that aim to find solutions for these challenges . In the theoretical framework of this dissertation, four governance configurations are derived from the interaction of varying actor types with regard to hierarchical and non-hierarchical steering of their interactions. These four governance configurations differ in decision-making responsibilities, accountability and delegation of tasks or direction of information flow. The assumption on actor relationships and steering is supplemented by possible alternative explanations in the empirical investigation, such as resource availability, the inheritance of structures and institutions from previous projects in a project context, gaining acceptance through beneficiaries (local legitimacy) as a door opener, and asymmetries of power in the project context. Case study evidence from seven projects reveals that the actors' relationship is important for successful project delivery. Additionally, the results show that there is a systematic difference between conventional and new donors. Projects led by conventional donors were consistently more successful, due to an actor relationship that placed the responsibility in the hands of the recipient actors and benefited from the trust and reputation of a long-term cooperation. The trust and reputation of conventional donors always went along with a back-up from federal level and trickled down as reputation also at local level implementation. Furthermore, charismatic leaders, as well as the acquired structures and institutions of predecessor projects, also proved to be a positive influencing factor for successful project implementation. Despite the mixed results of the seven case studies, central recommendations for action can be derived for the various actors involved in development cooperation. For example, new donors could fulfill a supplementary function with conventional donors by developing innovative project approaches through pilot studies and then implementing them as a supplement to the projects of conventional donors on the ground. In return, conventional donors would have to make room the new donors by integrating their approaches into already programs in order to promote donor harmonization. It is also important to identify and occupy niches for activities and to promote harmonization among donors on state and federal sides. The empirical results demonstrate the need for a harmonization strategy of different donor types in order to prevent duplication, over-experimentation and the failure of development programs. A transformation to successful and sustainable development cooperation can only be achieved through more coordination processes and national self-responsibility. N2 - In der Entwicklungszusammenarbeit (EZ) wurden in den vergangenen Jahrzehnten herkömmliche bi- und multilaterale EZ-Geber durch eine Vielzahl kleinerer, privater oder privat-öffentlicher Geber ergänzt. Es stellt sich nun die Frage nach der Effektivität dieser neuen Geber im Vergleich zu den bisherigen. Die neuen Geber setzen ebenfalls EZ-Maßnahmen um und haben sich einem Mehr an Pragmatismus, Innovation und Flexibilität verschrieben. Sie stehen jedoch auch in der Kritik, die Funktion der lokalen Zivilgesellschaft zu schwächen und in fragilen Kontexten eine intransparente und oft umstrittene Alternative zur staatlichen Daseinsvorsorge darzustellen. Das transformative Potential dieser neuen Geber durch zusätzliche EZ-Gelder und für bessere Entwicklung ist in der Literatur umstritten. In der vorliegenden Dissertation erfolgt ein Vergleich der neuen und herkömmlichen Geber hinsichtlich ihrer Effektivität in der Erbringung von öffentlichen Gütern und Dienstleistungen im Wasser- und Abwasserbereich in Indien. Indien bietet sich als Länderkontext für die Untersuchung dieser Forschungsfrage insbesondere an, da es sich als Schwellenland mit gegenwärtig immer noch sehr hoher Armut und schlechter Wasserversorgung in vorwiegend ländlichen Gebieten einer Vielzahl von Akteuren und Ansätzen zur Lösung dieser Herausforderungen gegenüber sieht. Im theoretischen Rahmen der Dissertation werden aus dem Zusammenspiel von Akteurstypen und hierarchischer und nicht-hierarchischer Steuerung, vier Governance-Typen entwickelt. Diese vier Steuerungsmodi unterscheiden sich hinsichtlich der Entscheidungsfindung, Rechenschaftslegung und Delegierung von Aufgaben bzw. Richtung des Informationsflusses. Diese Governance-Typen werden in der empirischen Untersuchung um mögliche alternative Erklärungen ergänzt wie Ressourcenverfügbarkeit, Bedeutung von vorhergehenden Projekten in einem Projektkontext, lokale Legitimität als Türöffner und Machtasymmetrien im Projektkontext. Die empirische Analyse von sieben Fällen macht deutlich, dass die Akteursbeziehung eine notwendige Bedingung für erfolgreiche und eigenständige Projektumsetzung in der EZ ist. Darüber hinaus belegen die Ergebnisse, dass es einen systematischen Unterschied zwischen herkömmlichen und neuen Gebern gibt. Die Projekte der herkömmlichen Geber waren durchweg erfolgreicher und wiesen alle eine Akteursinteraktion auf, die die Verantwortung in die Hände des EZ-Empfängers legte und darüber hinaus von Vertrauen und Reputation einer langjährigen Zusammenarbeit profitierten. Der Erfolg der herkömmlichen Geber basierte vorwiegend auf der Rückendeckung der lokalen Umsetzung durch die nationale Ebene. Neben charismatischen Führungsfiguren stellten sich auch übernommene Strukturen und Akteure von Vorgängerprojekten als positive Einflussfaktoren für eine erfolgreiche Projektumsetzung heraus. Aus den Erfolgen und Misserfolgen der sieben hier untersuchten Fälle lassen sich zentrale Handlungsempfehlungen für die unterschiedlichen Akteure der EZ-Umsetzung ableiten. So könnten neue Geber eine Ergänzungsfunktion zu herkömmlichen Gebern erfüllen, indem sie durch Pilotstudien innovative Projektansätze entwickeln und diese dann als Ergänzung zu den Projekten herkömmlicher Geber vor Ort umsetzen. Herkömmliche Geber müssten im Gegenzug in ihren Programmen Raum für die Integration der Ansätze von neuen Gebern schaffen, um so eine Geberharmonisierung zu fördern. Auf staatlicher und bundesstaatlicher Nehmerseite gilt es ebenfalls, Nischen für Aktivitäten zu identifizieren und zu besetzen und die Harmonisierung unter den Gebern zu fördern. Die empirischen Ergebnisse belegen die Notwendigkeit einer Harmonisierungsstrategie von unterschiedlichen Gebertypen, um vor Ort Duplikation, Experimente und Misserfolge von EZ-Programmen zu verhindern. Eine Transformation zu einer erfolgreichen und nachhaltigen EZ kann nur durch mehr Koordinationsprozesse und nationale Eigenverantwortung erreicht werden. KW - governance KW - aid effectiveness KW - water development aid KW - development aid India KW - donor harmonization KW - actor interplay KW - new donors KW - conventional donors KW - donor reputation KW - governance KW - Wirksamkeit der Entwicklungszusammenarbeit KW - Wasserentwicklungszusammenarbeit KW - Entwicklungszusammenarbeit mit Indien KW - Geberharmonisierung KW - Akteursinteraktion KW - neue Geber KW - herkömmliche Geber KW - Reputation der Geber Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-401337 ER - TY - JOUR A1 - Singh, Alka A1 - Seitz, Florian A1 - Eicker, Annette A1 - Güntner, Andreas T1 - Water Budget Analysis within the Surrounding of Prominent Lakes and Reservoirs from Multi-Sensor Earth Observation Data and Hydrological Models: Case Studies of the Aral Sea and Lake Mead JF - Remote sensing N2 - The hydrological budget of a region is determined based on the horizontal and vertical water fluxes acting in both inward and outward directions. These integrated water fluxes vary, altering the total water storage and consequently the gravitational force of the region. The time-dependent gravitational field can be observed through the Gravity Recovery and Climate Experiment (GRACE) gravimetric satellite mission, provided that the mass variation is above the sensitivity of GRACE. This study evaluates mass changes in prominent reservoir regions through three independent approaches viz. fluxes, storages, and gravity, by combining remote sensing products, in-situ data and hydrological model outputs using WaterGAP Global Hydrological Model (WGHM) and Global Land Data Assimilation System (GLDAS). The results show that the dynamics revealed by the GRACE signal can be better explored by a hybrid method, which combines remote sensing-based reservoir volume estimates with hydrological model outputs, than by exclusive model-based storage estimates. For the given arid/ semi-arid regions, GLDAS based storage estimations perform better than WGHM. KW - GRACE KW - water budget KW - reservoir KW - water fluxes KW - GLDAS KW - WGHM KW - Aral Sea KW - Lake Mead Y1 - 2016 U6 - https://doi.org/10.3390/rs8110953 SN - 2072-4292 VL - 8 PB - MDPI CY - Basel ER - TY - GEN A1 - Singh, Alka A1 - Seitz, Florian A1 - Eicker, Annette A1 - Güntner, Andreas T1 - Water budget analysis within the surrounding of prominent lakes and reservoirs from multi-sensor earth observation data and hydrological models BT - case studies of the Aral Sea and Lake Mead T2 - remote sensing N2 - The hydrological budget of a region is determined based on the horizontal and vertical water fluxes acting in both inward and outward directions. These integrated water fluxes vary, altering the total water storage and consequently the gravitational force of the region. The time-dependent gravitational field can be observed through the Gravity Recovery and Climate Experiment (GRACE) gravimetric satellite mission, provided that the mass variation is above the sensitivity of GRACE. This study evaluates mass changes in prominent reservoir regions through three independent approaches viz. fluxes, storages, and gravity, by combining remote sensing products, in-situ data and hydrological model outputs using WaterGAP Global Hydrological Model (WGHM) and Global Land Data Assimilation System (GLDAS). The results show that the dynamics revealed by the GRACE signal can be better explored by a hybrid method, which combines remote sensing-based reservoir volume estimates with hydrological model outputs, than by exclusive model-based storage estimates. For the given arid/ semi-arid regions, GLDAS based storage estimations perform better than WGHM. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 453 KW - GRACE KW - water budget KW - reservoir KW - water fluxes KW - GLDAS KW - WGHM KW - Aral Sea KW - Lake Mead Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-407902 ER - TY - JOUR A1 - Reppert, Alexander von A1 - Sarhan, Radwan Mohamed A1 - Stete, Felix A1 - Pudell, Jan-Etienne A1 - Del Fatti, N. A1 - Crut, A. A1 - Koetz, Joachim A1 - Liebig, Ferenc A1 - Prietzel, Claudia Christina A1 - Bargheer, Matias T1 - Watching the Vibration and Cooling of Ultrathin Gold Nanotriangles by Ultrafast X-ray Diffraction JF - The journal of physical chemistry : C, Nanomaterials and interfaces N2 - We study the vibrations of ultrathin gold nanotriangles upon optical excitation of the electron gas by ultrafast X-ray diffraction. We quantitatively measure the strain evolution in these highly asymmetric nano-objects, providing a direct estimation of the amplitude and phase of the excited vibrational motion. The maximal strain value is well reproduced by calculations addressing pump absorption by the nanotriangles and their resulting thermal expansion. The amplitude and phase of the out-of-plane vibration mode with 3.6 ps period dominating the observed oscillations are related to two distinct excitation mechanisms. Electronic and phonon pressures impose stresses with different time dependences. The nanosecond relaxation of the expansion yields a direct temperature sensing of the nano-object. The presence of a thin organic molecular layer at the nanotriangle/substrate interfaces drastically reduces the thermal conductance to the substrate. Y1 - 2016 U6 - https://doi.org/10.1021/acs.jpcc.6b11651 SN - 1932-7447 VL - 120 SP - 28894 EP - 28899 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Krahé, Barbara T1 - Vulnerability to Sexual Victimization in Female and Male College Students in Brazil: Cross-Sectional and Prospective Evidence JF - Archives of sexual behavior : the official publication of the International Academy of Sex Research N2 - Using both cross-sectional and prospective analyses, this study examined vulnerability factors for sexual victimization in 541 female and male Brazilian college students, of whom a subgroup of 250 took part in two measurements 6 months apart. Risk factors for sexual victimization (alcohol consumption, casual sex, and ambiguous communication) in participants’ cognitive scripts for consensual sex were linked to sexual victimization via their translation into risky sexual behavior. Pornography use was indirectly linked to sexual victimization through its influence on risky sexual scripts and sexual behavior. Child sexual abuse predicted sexual victimization in the cross-sectional analysis, and victimization since age 14 predicted revictimization in the six months covered by the prospective period. Few gender differences were found. This study is the first prospective investigation of vulnerability factors for sexual victimization in Brazil, and similarities to evidence from North America are discussed. KW - Sexual victimization KW - Brazil KW - Sexual scripts KW - Pornography use KW - Childhood sexual abuse KW - Risky sexual behavior Y1 - 2016 U6 - https://doi.org/10.1007/s10508-014-0451-7 SN - 0004-0002 SN - 1573-2800 VL - 45 SP - 1101 EP - 1115 PB - Springer CY - New York ER - TY - GEN A1 - Reimold, W. U. A1 - Schulz, Toni A1 - Hoffmann, M. A1 - Wannek, Dshamilja A1 - Hauser, N. A1 - van Acken, David A1 - Luguet, A. T1 - VREDEFORT GRANOPHYRE GENESIS: CLUES FROM RE-OS ISOTOPE DATA T2 - Physical review : E, Statistical, nonlinear and soft matter physics Y1 - 2016 SN - 1086-9379 SN - 1945-5100 VL - 51 SP - A533 EP - A533 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Mumm, Rebekka A1 - Hermanussen, Michael A1 - Scheffler, Christiane T1 - voice break as the marker of biological age JF - Acta paediatrica : nurturing the child N2 - Aim: We aimed to develop the first references for body height, body weight and body mass index (BMI) for boys based on the individual developmental tempo with respect to their voice break status. Methods: We re-analysed data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS study) on body height, body weight and body mass index based on the voice break, or mutation, in 3956 boys aged 10-17 years. We used the LMS method to construct smoothed references centiles for the studied variables in premutational, mutational and postmutational boys. Results: Body height, body weight and BMI differed significantly (p < 0.001) between the different stages of voice break. On average, boys were 5.9 cm taller, 5.8 kg heavier and had a 0.7 kg/m(2) higher BMI with every higher stage of voice break. Currently used growth references for chronological age in comparison with maturity-related references led to an average of 5.4% of boys being falsely classified as overweight. KW - Body mass index KW - Developmental tempo KW - Growth reference values KW - Overweight KW - Voice break Y1 - 2016 U6 - https://doi.org/10.1111/apa.13488 SN - 0803-5253 SN - 1651-2227 VL - 105 SP - e459 EP - e463 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - de Guevara, Berit Bliesemann T1 - visits in zones of conflict and intervention JF - Journal of intervention and statebuilding N2 - This article explores the practice and political significance of politicians’ journeys to conflict zones. It focuses on the German example, looking at field trips to theatres of international intervention as a way of first-hand knowledge in policymaking. Paying tribute to Lisa Smirl and her work on humanitarian spaces, objects and imaginaries and on liminality in aid worker biographies, two connected arguments are developed. First, through the exploration of the routinized practices of politicians’ field trips the article shows how these journeys not only remain confined to the ‘auxiliary space’ of aid/intervention, but that it is furthermore a staged reality of this auxiliary space that most politicians experience on their journeys. The question is then asked, second, what politicians actually experience on their journeys and how their experiences relate to their policy knowledge about conflict and intervention. It is shown that political field trips enable sensory/affectual, liminoid and liminal experiences, which have functions such as authority accumulation, agenda setting, community building, and civilizing domestic politics, while at the same time reinforcing, in most cases, pre-existing conflict and intervention imaginaries. KW - field trips KW - on-site visits KW - battlefield tourism KW - sensory experience KW - affect KW - conflict knowledge KW - spaces of aid KW - liminality KW - German Bundestag KW - parliamentarians KW - German foreign policy KW - Lisa Smirl Y1 - 2016 U6 - https://doi.org/10.1080/17502977.2015.1137394 SN - 1750-2977 SN - 1750-2985 VL - 10 SP - 56 EP - 76 PB - Soil Science Society of America CY - Abingdon ER - TY - JOUR A1 - Adel, Mustafa A1 - Elbehery, Ali H. A. A1 - Aziz, Sherry K. A1 - Aziz, Ramy K. A1 - Grossart, Hans-Peter A1 - Siam, Rania T1 - Viruses-to-mobile genetic elements skew in the deep Atlantis II brine pool sediments JF - Scientific reports N2 - The central rift of the Red Sea has 25 brine pools with different physical and geochemical characteristics. Atlantis II (ATIID), Discovery Deeps (DD) and Chain Deep (CD) are characterized by high salinity, temperature and metal content. Several studies reported microbial communities in these brine pools, but few studies addressed the brine pool sediments. Therefore, sediment cores were collected from ATIID, DD, CD brine pools and an adjacent brine-influenced site. Sixteen different lithologic sediment sections were subjected to shotgun DNA pyrosequencing to generate 1.47 billion base pairs (1.47 x 10(9) bp). We generated sediment-specific reads and attempted to annotate all reads. We report the phylogenetic and biochemical uniqueness of the deepest ATIID sulfur-rich brine pool sediments. In contrary to all other sediment sections, bacteria dominate the deepest ATIID sulfur-rich brine pool sediments. This decrease in virus-to-bacteria ratio in selected sections and depth coincided with an overrepresentation of mobile genetic elements. Skewing in the composition of viruses-to-mobile genetic elements may uniquely contribute to the distinct microbial consortium in sediments in proximity to hydrothermally active vents of the Red Sea and possibly in their surroundings, through differential horizontal gene transfer. Y1 - 2016 U6 - https://doi.org/10.1038/srep32704 SN - 2045-2322 VL - 6 SP - 8882 EP - 8888 PB - Nature Publ. Group CY - London ER - TY - GEN A1 - Krahé, Barbara T1 - Violent Media Effects on Aggression: A Commentary from a Cross-Cultural Perspective T2 - Analyses of social issues and public policy N2 - It is argued that, despite differences in cultural norms and practices, the evidence for a link between violent media use and aggression is remarkably consistent across different countries. Along with evidence that different operationalizations of violent media use also converge across countries, these findings strengthen the conclusion that violent media are a risk factor for aggression and validate the psychological explanations for these effects. However, we need comparative studies based on a consistent methodology and a theory-based selection of cultural difference variables to properly examine the potential impact of culture on the association between violent media use and aggression. Y1 - 2016 U6 - https://doi.org/10.1111/asap.12107 SN - 1529-7489 SN - 1530-2415 VL - 16 SP - 439 EP - 442 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Rauch, Thomas A1 - Quinet, P. A1 - Hoyer, D. A1 - Werner, K. A1 - Richter, Philipp A1 - Kruk, J. W. A1 - Demleitner, M. T1 - VII. New Kr IV - VII oscillator strengths and an improved spectral analysis of the hot, hydrogen-deficient DO-type white dwarf RE 0503-289 JF - Plant physiology : an international journal devoted to physiology, biochemistry, cellular and molecular biology, biophysics and environmental biology of plants N2 - Context. For the spectral analysis of high-resolution and high signal-to-noise (S/N) spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation. Aims. New Kr IV-VII oscillator strengths for a large number of lines enable us to construct more detailed model atoms for our NLTE model-atmosphere calculations. This enables us to search for additional Kr lines in observed spectra and to improve Kr abundance determinations. Methods. We calculated Kr IV-VII oscillator strengths to consider radiative and collisional bound-bound transitions in detail in our NLTE stellar-atmosphere models for the analysis of Kr lines that are exhibited in high-resolution and high S/N ultraviolet (UV) observations of the hot white dwarf RE 0503-289. Results. We reanalyzed the effective temperature and surface gravity and determined T-eff = 70 000 +/- 2000 K and log (g/cm s(-2)) = 7.5 +/- 0.1. We newly identified ten Kr V lines and one Kr vi line in the spectrum of RE 0503-289. We measured a Kr abundance of 3.3 +/- 0.3 (logarithmic mass fraction). We discovered that the interstellar absorption toward RE 0503-289 has a multi-velocity structure within a radial-velocity interval of -40 km s(-1) < upsilon(rad) < +18 km s(-1). Conclusions. Reliable measurements and calculations of atomic data are a prerequisite for state-of-the-art NLTE stellar-atmosphere modeling. Observed Kr V-VII line profiles in the UV spectrum of the white dwarf RE 0503-289 were simultaneously well reproduced with our newly calculated oscillator strengths. KW - atomic data KW - line: identification KW - stars: abundances KW - stars: individual: RE 0503-289 KW - virtual observatory tools KW - stars: individual: RE 0457-281 Y1 - 2016 U6 - https://doi.org/10.1051/0004-6361/201628131 SN - 1432-0746 VL - 590 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Kunnus, Kristjan A1 - Zhang, Wenkai A1 - Delcey, Mickael G. A1 - Pinjari, Rahul V. A1 - Miedema, Piter S. A1 - Schreck, Simon A1 - Quevedo, Wilson A1 - Schröder, Henning A1 - Föhlisch, Alexander A1 - Gaffney, Kelly J. A1 - Lundberg, Marcus A1 - Odelius, Michael A1 - Wernet, Philippe T1 - Viewing the Valence Electronic Structure of Ferric and Ferrous Hexacyanide in Solution from the Fe and Cyanide Perspectives JF - The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces & biophysical chemistry N2 - The valence-excited states of ferric and ferrous hexacyanide ions in aqueous solution were mapped by resonant inelastic X-ray scattering (RIXS) at the Fe L-2,L-3 and N K edges. Probing of both the central Fe and the ligand N atoms enabled identification of the metal-and ligand-centered excited states, as well as ligand-to-metal and metal-to-ligand charge-transfer excited states. Ab initio calculations utilizing the RASPT2 method were used to simulate the Fe L-2,L-3-edge RIXS spectra and enabled quantification of the covalencies of both occupied and empty orbitals of pi and sigma symmetry. We found that pi back-donation in the ferric complex is smaller than that in the ferrous complex. This is evidenced by the relative amounts of Fe 3d character in the nominally 2 pi CN- molecular orbital of 7% and 9% in ferric and ferrous hexacyanide, respectively. Utilizing the direct sensitivity of Fe L-3-edge RIXS to the Fe 3d character in the occupied molecular orbitals, we also found that the donation interactions are dominated by sigma bonding. The latter was found to be stronger in the ferric complex, with an Fe 3d contribution to the nominally 5 sigma CN- molecular orbitals of 29% compared to 20% in the ferrous complex. These results are consistent with the notion that a higher charge at the central metal atom increases donation and decreases back-donation. Y1 - 2016 U6 - https://doi.org/10.1021/acs.jpcb.6b04751 SN - 1520-6106 VL - 120 SP - 7182 EP - 7194 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Aliu, E. A1 - Archambault, S. A1 - Archer, A. A1 - Arlen, T. A1 - Aune, T. A1 - Barnacka, Anna A1 - Behera, B. A1 - Beilicke, M. A1 - Benbow, W. A1 - Berger, K. A1 - Bird, R. A1 - Böttcher, Markus A1 - Bouvier, A. A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Cardenzana, J. V. A1 - Cerruti, M. A1 - Cesarini, A. A1 - Chen, Xuhui A1 - Ciupik, L. A1 - Collins-Hughes, E. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dumm, J. A1 - Eisch, J. D. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gall, D. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Griffiths, S. T. A1 - Grube, J. A1 - Gyuk, G. A1 - Hütten, M. A1 - Hakansson, Nils A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krause, M. A1 - Krawczynski, H. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Meagher, K. A1 - Millis, J. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Orr, M. A1 - Otte, A. N. A1 - Pandel, D. A1 - Park, N. A1 - Pelassa, V. A1 - Perkins, J. S. A1 - Pichel, A. A1 - Pohl, Martin A1 - Popkow, A. A1 - Quinn, J. A1 - Ragan, K. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Roache, E. A1 - Rousselle, J. A1 - Rovero, A. C. A1 - Saxon, D. B. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Sheidaei, F. A1 - Skole, C. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Theiling, M. A1 - Todd, N. W. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Varlotta, A. A1 - Vassiliev, V. V. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Welsing, R. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Zitzer, B. A1 - Baring, M. G. A1 - Gonzalez, J. Becerra A1 - Cillis, A. N. A1 - Horan, D. A1 - Paneque, D. T1 - Very high energy outburst of Markarian 501 in May 2009 JF - Physical chemistry, chemical physics : a journal of European Chemical Societies N2 - The very high energy (VHE; E > 100 GeV) blazar Markarian 501 was observed between April 17 and May 5 (MJD 54 938-54 956), 2009, as part of an extensive multiwavelength campaign from radio to VHE. Strong VHE yray activity was detected on May 1st with Whipple and VERITAS, when the flux (E > 400 GeV) increased to 10 times the preflare baseline flux (3.9 x 10(-11) ph cm(-2) s(-1)), reaching five times the flux of the Crab Nebula. This coincided with a decrease in the optical polarization and a rotation of the polarization angle by 15. This VHE flare showed a fast flux variation with an increase of a factor similar to 4 in 25 min, and a falling time of similar to 50 min. We present the observations of the quiescent state previous to the flare and of the high state after the flare, focusing on the flux and spectral variability from Whipple, VERITAS, Fermi-LAT, RXTE, and Swift combined with optical and radio data. KW - BL Lacertae objects: individual: Mrk 501 KW - gamma rays: galaxies Y1 - 2016 U6 - https://doi.org/10.1051/0004-6361/201628744 SN - 1432-0746 VL - 594 PB - EDP Sciences CY - Les Ulis ER - TY - GEN A1 - Schick, Daniel A1 - Eckert, Sebastian A1 - Pontius, Niko A1 - Mitzner, Rolf A1 - Föhlisch, Alexander A1 - Holldack, Karsten A1 - Sorgenfrei, Nomi T1 - Versatile soft X-ray-optical cross-correlator for ultrafast applications T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - We present an X-ray-optical cross-correlator for the soft (> 150 eV) up to the hard X-ray regime based on a molybdenum-silicon superlattice. The cross-correlation is done by probing intensity and position changes of superlattice Bragg peaks caused by photoexcitation of coherent phonons. This approach is applicable for a wide range of X-ray photon energies as well as for a broad range of excitation wavelengths and requires no external fields or changes of temperature. Moreover, the cross-correlator can be employed on a 10 ps or 100 fs time scale featuring up to 50% total X-ray reflectivity and transient signal changes of more than 20%. (C) 2016 Author(s). T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1331 Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-436962 SN - 1866-8372 IS - 1331 SP - 054304-1 EP - 054304-8 ER - TY - JOUR A1 - Schick, Daniel A1 - Eckert, Sebastian A1 - Pontius, Niko A1 - Mitzner, Rolf A1 - Föhlisch, Alexander A1 - Holldack, Karsten A1 - Sorgenfrei, Nomi T1 - Versatile soft X-ray-optical cross-correlator for ultrafast applications JF - Structural dynamics N2 - We present an X-ray-optical cross-correlator for the soft (> 150 eV) up to the hard X-ray regime based on a molybdenum-silicon superlattice. The cross-correlation is done by probing intensity and position changes of superlattice Bragg peaks caused by photoexcitation of coherent phonons. This approach is applicable for a wide range of X-ray photon energies as well as for a broad range of excitation wavelengths and requires no external fields or changes of temperature. Moreover, the cross-correlator can be employed on a 10 ps or 100 fs time scale featuring up to 50% total X-ray reflectivity and transient signal changes of more than 20%. (C) 2016 Author(s). Y1 - 2016 U6 - https://doi.org/10.1063/1.4964296 SN - 2329-7778 VL - 3 SP - 054304-1 EP - 054304-8 PB - American Institute of Physics CY - Melville ER - TY - JOUR A1 - Abeysekara, A. U. A1 - Archambault, S. A1 - Archer, A. A1 - Benbow, W. A1 - Bird, R. A1 - Biteau, Jonathan A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Byrum, K. A1 - Cardenzana, J. V. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Christiansen, J. L. A1 - Ciupik, L. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dickinson, H. J. A1 - Dumm, J. A1 - Eisch, J. D. A1 - Errando, M. A1 - Falcone, A. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Flinders, A. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Gyuk, G. A1 - Huetten, M. A1 - Hanna, D. A1 - Holder, J. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Meagher, K. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Pelassa, V. A1 - Petrashyk, A. A1 - Petry, D. A1 - Pohl, Martin A1 - Popkow, A. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Ratliff, G. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Reynolds, K. A1 - Richards, G. T. A1 - Roache, E. A1 - Rulten, C. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Zitzer, B. T1 - VERITAS and multiwavelength observations of the BL Lacertae object 1ES 1741+196 JF - Monthly notices of the Royal Astronomical Society N2 - We present results from multiwavelength observations of the BL Lacertae object 1ES 1741 + 196, including results in the very high energy gamma-ray regime using the Very Energetic Radiation Imaging Telescope Array System (VERITAS). The VERITAS time-averaged spectrum, measured above 180 GeV, is well modelled by a power law with a spectral index of 2.7 +/- 0.7(stat) +/- 0.2(syst). The integral flux above 180 GeV is (3.9 +/- 0.8(stat) +/- 1.0(syst)) x 10(-8) m(-2) s(-1), corresponding to 1.6 per cent of the Crab nebula flux on average. The multiwavelength spectral energy distribution of the source suggests that 1ES 1741+196 is an extreme-high-frequency-peaked BL Lacertae object. The observations analysed in this paper extend over a period of six years, during which time no strong flares were observed in any band. This analysis is therefore one of the few characterizations of a blazar in a non-flaring state. KW - astroparticle physics KW - relativistic processes KW - galaxies: individual: 1ES 1741+196=VER J1744+195 Y1 - 2016 U6 - https://doi.org/10.1093/mnras/stw664 SN - 0035-8711 SN - 1365-2966 VL - 459 SP - 2550 EP - 2557 PB - Oxford Univ. Press CY - Oxford ER - TY - GEN A1 - Kneis, David A1 - Abon, Catherine Cristobal A1 - Bronstert, Axel A1 - Heistermann, Maik T1 - Verification of short-term runoff forecasts for a small Philippine basin (Marikina) T2 - Hydrological sciences journal = Journal des sciences hydrologiques N2 - Storm runoff from the Marikina River Basin frequently causes flood events in the Philippine capital region Metro Manila. This paper presents and evaluates a system to predict short-term runoff from the upper part of that basin (380km(2)). It was designed as a possible component of an operational warning system yet to be installed. For the purpose of forecast verification, hindcasts of streamflow were generated for a period of 15 months with a time-continuous, conceptual hydrological model. The latter was fed with real-time observations of rainfall. Both ground observations and weather radar data were tested as rainfall forcings. The radar-based precipitation estimates clearly outperformed the raingauge-based estimates in the hydrological verification. Nevertheless, the quality of the deterministic short-term runoff forecasts was found to be limited. For the radar-based predictions, the reduction of variance for lead times of 1, 2 and 3hours was 0.61, 0.62 and 0.54, respectively, with reference to a no-forecast scenario, i.e. persistence. The probability of detection for major increases in streamflow was typically less than 0.5. Given the significance of flood events in the Marikina Basin, more effort needs to be put into the reduction of forecast errors and the quantification of remaining uncertainties. Y1 - 2016 U6 - https://doi.org/10.1080/02626667.2016.1183773 SN - 0262-6667 SN - 2150-3435 VL - 62 SP - 205 EP - 216 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Klemm, Juliane A1 - Herzschuh, Ulrike A1 - Pestryakova, Luidmila Agafyevna T1 - Vegetation, climate and lake changes over the last 7000 years at the boreal treeline in north-central Siberia JF - Quaternary science reviews : the international multidisciplinary research and review journal KW - Tundra-taiga ecotone KW - Larix gmelinii KW - Palynology KW - Sediment geochemistry KW - Mean July temperature KW - Ordination KW - WA-PLS KW - Procrustes rotation Y1 - 2016 U6 - https://doi.org/10.1016/j.quascirev.2015.08.015 SN - 0277-3791 VL - 147 SP - 422 EP - 434 PB - Elsevier CY - Oxford ER - TY - THES A1 - Niemeyer, Bastian T1 - Vegetation reconstruction and assessment of plant diversity at the treeline ecotone in northern Siberia Y1 - 2016 ER - TY - JOUR A1 - Zibulski, Romy A1 - Herzschuh, Ulrike A1 - Pestryakova, Luidmila Agafyevna T1 - Vegetation patterns along micro-relief and vegetation type transects in polygonal landscapes of the Siberian Arctic JF - Journal of vegetation science N2 - QuestionHow important is the effect of micro-relief and vegetation type on the characteristics of vascular plants and bryophytes in low-centred polygons? LocationSiberian Arctic, Russia. MethodsEight low-centred polygons in northern Siberia were surveyed for vegetation along transects running from the rim to the pond via the rim-pond transition of each polygon and across a vegetation type gradient from open forest to tundra. ResultsThe cover of vascular plants and bryophytes displays no significant differences between the rim and rim-pond transition but is significantly lower in the pond section of the polygons. Alpha-diversity of vascular plants decreases strongly from rim to pond, whereas bryophyte diversity in pond plots is significantly distinct from the rim and the rim-pond transition. There is no clear trend in cover for either plant group along the vegetation type transect and only a weak trend in -diversity. However, both gradients are reflected in the compositional turnover. The applied indicator species analysis identified taxa characteristic of certain environmental conditions. Among others, we found vascular plants primarily characteristic of the rim and bryophyte taxa characteristic of each micro-relief level and vegetation type. ConclusionsThe observed gradual pattern in -diversity and composition of polygonal vegetation suggests that micro-relief is the main driver of changes in the vegetation composition, while vegetation type and the related forest cover change are of subordinate importance for polygonal vegetation patterns along the Siberian tree line. KW - Bryophytes KW - Indicator species KW - Low-centred polygon KW - NMDS KW - Russia KW - Tree line KW - Tundra KW - Vascular plants Y1 - 2016 U6 - https://doi.org/10.1111/jvs.12356 SN - 1100-9233 SN - 1654-1103 VL - 27 SP - 377 EP - 386 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Carus, Jana A1 - Paul, Maike A1 - Schroeder, Boris T1 - Vegetation as self-adaptive coastal protection: Reduction of current velocity and morphologic plasticity of a brackish marsh pioneer JF - Ecology and evolution N2 - By reducing current velocity, tidal marsh vegetation can diminish storm surges and storm waves. Conversely, currents often exert high mechanical stresses onto the plants and hence affect vegetation structure and plant characteristics. In our study, we aim at analysing this interaction from both angles. On the one hand, we quantify the reduction of current velocity by Bolboschoenus maritimus, and on the other hand, we identify functional traits of B. maritimus’ ramets along environmental gradients. Our results show that tidal marsh vegetation is able to buffer a large proportion of the flow velocity at currents under normal conditions. Cross-shore current velocity decreased with distance from the marsh edge and was reduced by more than 50% after 15 m of vegetation. We were furthermore able to show that plants growing at the marsh edge had a significantly larger diameter than plants from inside the vegetation. We found a positive correlation between plant thickness and cross-shore current which could provide an adaptive value in habitats with high mechanical stress. With the adapted morphology of plants growing at the highly exposed marsh edge, the entire vegetation belt is able to better resist the mechanical stress of high current velocities. This self-adaptive effect thus increases the ability of B. maritimus to grow and persist in the pioneer zone and may hence better contribute to ecosystem-based coastal protection by reducing current velocity. KW - Adaptive value KW - Bolboschoenus maritimus KW - brackish marsh KW - flow velocity KW - mechanical pressure KW - morphological adaptation KW - phenotypic plasticity KW - pioneer zone Y1 - 2016 U6 - https://doi.org/10.1002/ece3.1904 SN - 2045-7758 VL - 6 SP - 1579 EP - 1589 PB - Wiley CY - Hoboken ER - TY - INPR A1 - Alsaedy, Ammar T1 - Variational primitive of a differential form N2 - In this paper we specify the Dirichlet to Neumann operator related to the Cauchy problem for the gradient operator with data on a part of the boundary. To this end, we consider a nonlinear relaxation of this problem which is a mixed boundary problem of Zaremba type for the p-Laplace equation. T3 - Preprints des Instituts für Mathematik der Universität Potsdam - 5 (2016) 4 KW - Dirichlet-to-Neumann operator KW - Cauchy problem KW - p-Laplace operator KW - calculus of variations Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-89223 SN - 2193-6943 VL - 5 IS - 4 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Wolff, Wanja A1 - Sandouqa, Yaser A1 - Brand, Ralf T1 - Using, the simple sample count to estimate the frequency of prescription drug neuroenhancement in a sample of Jordan employees JF - International journal of drug policy N2 - Background: Epidemiological research indicates that the use of prescription drugs to enhance cognitive functioning is prevalent in Western countries, however, research on this phenomenon in Arab countries is lacking. Our study aimed to investigate the frequency of neuroenhancement (NE) using prescription drugs in a sample of employees in Jordan. Methods: A sample of 1186 employees (37.11 +/- 8.37 years old, 495 female), of whom 723 (35.65 +/- 7.53 years old, 396 female) served as teachers, completed a paper-pencil questionnaire. The single sample count technique (SSC) was used in order to secure confidential, self-reporting of prescription drug NE. Results: The 12-month prevalence of NE, estimated with the SSC was 15.43%. At 26.16%, the prevalence estimate was markedly higher in the subsample of teachers compared to non-teachers, 0.29%. Surprisingly, 336 participants did not use the SSC and directly affirmed or denied prescription drug NE. These direct responses yielded a prevalence of 11.57% for the full sample, 9.73% for the teachers and 15.60% for the non-teachers. Conclusion: This is the first study of the frequency of NE in an Arab sample. Results indicate that the use of prescription drug NE is not limited to Western countries and that teachers in Jordan might constitute a high-risk population. Further, participants seem to differ in their use of indirect estimation methods for reporting prescription drug NE. For future research, it might be useful to triangulate standard self reports and indirect estimation methods to assess NE. Possible cultural differences and specific high-risk populations for NE should be investigated further. (C) 2015 Elsevier B.V. All rights reserved. KW - Neuroenhancement KW - Jordan KW - Single sample count Y1 - 2016 U6 - https://doi.org/10.1016/j.drugpo.2015.12.014 SN - 0955-3959 SN - 1873-4758 VL - 31 SP - 51 EP - 55 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kretschmer, Marlene A1 - Coumou, Dim A1 - Donges, Jonathan A1 - Runge, Jakob T1 - Using Causal Effect Networks to Analyze Different Arctic Drivers of Midlatitude Winter Circulation JF - Journal of climate N2 - In recent years, the Northern Hemisphere midlatitudes have suffered from severe winters like the extreme 2012/13 winter in the eastern United States. These cold spells were linked to a meandering upper-tropospheric jet stream pattern and a negative Arctic Oscillation index (AO). However, the nature of the drivers behind these circulation patterns remains controversial. Various studies have proposed different mechanisms related to changes in the Arctic, most of them related to a reduction in sea ice concentrations or increasing Eurasian snow cover. Here, a novel type of time series analysis, called causal effect networks (CEN), based on graphical models is introduced to assess causal relationships and their time delays between different processes. The effect of different Arctic actors on winter circulation on weekly to monthly time scales is studied, and robust network patterns are found. Barents and Kara sea ice concentrations are detected to be important external drivers of the midlatitude circulation, influencing winter AO via tropospheric mechanisms and through processes involving the stratosphere. Eurasia snow cover is also detected to have a causal effect on sea level pressure in Asia, but its exact role on AO remains unclear. The CEN approach presented in this study overcomes some difficulties in interpreting correlation analyses, complements model experiments for testing hypotheses involving teleconnections, and can be used to assess their validity. The findings confirm that sea ice concentrations in autumn in the Barents and Kara Seas are an important driver of winter circulation in the midlatitudes. Y1 - 2016 U6 - https://doi.org/10.1175/JCLI-D-15-0654.1 SN - 0894-8755 SN - 1520-0442 VL - 29 SP - 4069 EP - 4081 PB - American Meteorological Soc. CY - Boston ER - TY - JOUR A1 - Brand, Ralf A1 - Koch, Helen T1 - Using Caffeine Pills for Performance Enhancement. An Experimental Study Neuroenhancements JF - Frontiers in psychology N2 - Recent research has indicated that university students sometimes use caffeine pills for neuroenhancement (NE; non-medical use of psychoactive substances or technology to produce a subjective enhancement in psychological functioning and experience), especially during exam preparation. In our factorial survey experiment, we manipulated the evidence participants were given about the prevalence of NE amongst peers and measured the resulting effects on the psychological predictors included in the Prototype-Willingness Model of risk behavior. Two hundred and thirty-one university students were randomized to a high prevalence condition (read faked research results overstating usage of caffeine pills amongst peers by a factor of 5; 50%), low prevalence condition (half the estimated prevalence; 5%) or control condition (no information about peer prevalence). Structural equation modeling confirmed that our participants’ willingness and intention to use caffeine pills in the next exam period could be explained by their past use of neuroenhancers, attitude to NE and subjective norm about use of caffeine pills whilst image of the typical user was a much less important factor. Provision of inaccurate information about prevalence reduced the predictive power of attitude with respect to willingness by 40-45%. This may be because receiving information about peer prevalence which does not fit with their perception of the social norm causes people to question their attitude. Prevalence information might exert a deterrent effect on NE via the attitude-willingness association. We argue that research into NE and deterrence of associated risk behaviors should be informed by psychological theory. KW - attitude KW - prevalence information KW - prototype-willingness-model KW - social reactivity KW - doping Y1 - 2016 U6 - https://doi.org/10.3389/fpsyg.2016.00101 SN - 1664-1078 VL - 7 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Brand, Ralf A1 - Koch, Helen T1 - Using Caffeine Pills for Performance Enhancement BT - An Experimental Study on University Students’ Willingness and Their Intention to Try Neuroenhancements JF - Frontiers in psychology N2 - Recent research has indicated that university students sometimes use caffeine pills for neuroenhancement (NE; non-medical use of psychoactive substances or technology to produce a subjective enhancement in psychological functioning and experience), especially during exam preparation. In our factorial survey experiment, we manipulated the evidence participants were given about the prevalence of NE amongst peers and measured the resulting effects on the psychological predictors included in the Prototype-Willingness Model of risk behavior. Two hundred and thirty-one university students were randomized to a high prevalence condition (read faked research results overstating usage of caffeine pills amongst peers by a factor of 5; 50%), low prevalence condition (half the estimated prevalence; 5%) or control condition (no information about peer prevalence). Structural equation modeling confirmed that our participants’ willingness and intention to use caffeine pills in the next exam period could be explained by their past use of neuroenhancers, attitude to NE and subjective norm about use of caffeine pills whilst image of the typical user was a much less important factor. Provision of inaccurate information about prevalence reduced the predictive power of attitude with respect to willingness by 40-45%. This may be because receiving information about peer prevalence which does not fit with their perception of the social norm causes people to question their attitude. Prevalence information might exert a deterrent effect on NE via the attitude-willingness association. We argue that research into NE and deterrence of associated risk behaviors should be informed by psychological theory. KW - attitude KW - prevalence information KW - prototype-willingness-model KW - social reactivity KW - doping Y1 - 2016 U6 - https://doi.org/10.3389/fpsyg.2016.00101 SN - 1664-1078 VL - 7 SP - 1 EP - 11 PB - Frontiers Research Foundation CY - Lausanne ER - TY - GEN A1 - Brand, Ralf A1 - Koch, Helen T1 - Using Caffeine Pills for Performance Enhancement BT - An Experimental Study on University Students’ Willingness and Their Intention to Try Neuroenhancements N2 - Recent research has indicated that university students sometimes use caffeine pills for neuroenhancement (NE; non-medical use of psychoactive substances or technology to produce a subjective enhancement in psychological functioning and experience), especially during exam preparation. In our factorial survey experiment, we manipulated the evidence participants were given about the prevalence of NE amongst peers and measured the resulting effects on the psychological predictors included in the Prototype-Willingness Model of risk behavior. Two hundred and thirty-one university students were randomized to a high prevalence condition (read faked research results overstating usage of caffeine pills amongst peers by a factor of 5; 50%), low prevalence condition (half the estimated prevalence; 5%) or control condition (no information about peer prevalence). Structural equation modeling confirmed that our participants’ willingness and intention to use caffeine pills in the next exam period could be explained by their past use of neuroenhancers, attitude to NE and subjective norm about use of caffeine pills whilst image of the typical user was a much less important factor. Provision of inaccurate information about prevalence reduced the predictive power of attitude with respect to willingness by 40-45%. This may be because receiving information about peer prevalence which does not fit with their perception of the social norm causes people to question their attitude. Prevalence information might exert a deterrent effect on NE via the attitude-willingness association. We argue that research into NE and deterrence of associated risk behaviors should be informed by psychological theory. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 286 KW - attitude KW - doping KW - prevalence information KW - prototype-willingness-model KW - social reactivity Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-90506 ER - TY - JOUR A1 - Mondal, Suvendu Sekhar A1 - Marquardt, Dorothea A1 - Janiak, Christoph A1 - Holdt, Hans-Jürgen T1 - Use of a 4,5-dicyanoimidazolate anion based ionic liquid for the synthesis of iron and silver nanoparticles JF - Dalton transactions : an international journal of inorganic chemistry N2 - Sixteen new ionic liquids (ILs) with tetraethylammonium, 1-butyl-3-methylimidazolium, 3-methyl-1-octylimidazolium and tetrabutylphosphonium cations paired with 2-substituted 4,5-dicyanoimidazolate anions (substituent at C2 = methyl, trifluoromethyl, pentafluoroethyl, N,N′-dimethyl amino and nitro) have been synthesized and characterized by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA). The effects of cation and anion type and structure of the resulting ILs, including several room temperature ionic liquids (RTILs), are reflected in the crystallization, melting points and thermal decomposition of the ILs. ILs exhibited large liquid and crystallization ranges and formed glasses on cooling with glass transition temperatures in the range of −22 to −71 °C. We selected one of the newly designed ILs due to its bigger size, compared to the common conventional IL anion and high electron-withdrawing nitrile group leads to an overall stabilization anion that may stabilize the metal nanoparticles. Stable and better separated iron and silver nanoparticles are obtained by the decomposition of corresponding Fe2(CO)9 and AgPF6, respectively, under N2-atmosphere in newly designed nitrile functionalized 4,5-dicyanoimidazolate anion based IL. Very small and uniform size for Fe-nanoparticles of about 1.8 ± 0.6 nm were achieved without any additional stabilizers or capping molecules. Comparatively bigger size of Ag-nanoparticles was obtained through the reduction of AgPF6 by hydrogen gas. Additionally, the AgPF6 precursor was decomposed under microwave irradiation (MWI), fabricating nut-in-shell-like, that is, core-separated-from-shell Ag-nano-structures. Y1 - 2016 U6 - https://doi.org/10.1039/C6DT00225K SN - 1477-9226 IS - 45 SP - 5476 EP - 5483 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Mondal, Suvendu Sekhar A1 - Marquardt, Dorothea A1 - Janiak, Christoph A1 - Holdt, Hans-Jürgen T1 - Use of a 4,5-dicyanoimidazolate anion based ionic liquid for the synthesis of iron and silver nanoparticles JF - Dalton transactions : a journal of inorganic chemistry, including bioinorganic, organometallic, and solid-state chemistry N2 - Sixteen new ionic liquids (ILs) with tetraethylammonium, 1-butyl-3-methylimidazolium, 3-methyl-1-octylimidazolium and tetrabutylphosphonium cations paired with 2-substituted 4,5-dicyanoimidazolate anions (substituent at C2 = methyl, trifluoromethyl, pentafluoroethyl, N,N′-dimethyl amino and nitro) have been synthesized and characterized by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA). The effects of cation and anion type and structure of the resulting ILs, including several room temperature ionic liquids (RTILs), are reflected in the crystallization, melting points and thermal decomposition of the ILs. ILs exhibited large liquid and crystallization ranges and formed glasses on cooling with glass transition temperatures in the range of −22 to −71 °C. We selected one of the newly designed ILs due to its bigger size, compared to the common conventional IL anion and high electron-withdrawing nitrile group leads to an overall stabilization anion that may stabilize the metal nanoparticles. Stable and better separated iron and silver nanoparticles are obtained by the decomposition of corresponding Fe2(CO)9 and AgPF6, respectively, under N2-atmosphere in newly designed nitrile functionalized 4,5-dicyanoimidazolate anion based IL. Very small and uniform size for Fe-nanoparticles of about 1.8 ± 0.6 nm were achieved without any additional stabilizers or capping molecules. Comparatively bigger size of Ag-nanoparticles was obtained through the reduction of AgPF6 by hydrogen gas. Additionally, the AgPF6 precursor was decomposed under microwave irradiation (MWI), fabricating nut-in-shell-like, that is, core-separated-from-shell Ag-nano-structures. Y1 - 2016 U6 - https://doi.org/10.1039/c6dt00225k SN - 1477-9226 SN - 1477-9234 VL - 45 SP - 5476 EP - 5483 PB - Royal Society of Chemistry CY - Cambridge ER - TY - GEN A1 - Chaykovska, Lyubov A1 - Heunisch, Fabian A1 - von Einem, Gina A1 - Alter, Markus L. A1 - Hocher, Carl-Friedrich A1 - Tsuprykov, Oleg A1 - Dschietzig, Thomas A1 - Kretschmer, Axel A1 - Hocher, Berthold T1 - Urinary vitamin D binding protein and KIM-1 are potent new biomarkers of major adverse renal events in patients undergoing coronary angiography T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Background Vitamin-D-binding protein (VDBP) is a low molecular weight protein that is filtered through the glomerulus as a 25-(OH) vitamin D 3/VDBP complex. In the normal kidney VDBP is reabsorbed and catabolized by proximal tubule epithelial cells reducing the urinary excretion to trace amounts. Acute tubular injury is expected to result in urinary VDBP loss. The purpose of our study was to explore the potential role of urinary VDBP as a biomarker of an acute renal damage. Method We included 314 patients with diabetes mellitus or mild renal impairment undergoing coronary angiography and collected blood and urine before and 24 hours after the CM application. Patients were followed for 90 days for the composite endpoint major adverse renal events (MARE: need for dialysis, doubling of serum creatinine after 90 days, unplanned emergency rehospitalization or death). Results Increased urine VDBP concentration 24 hours after contrast media exposure was predictive for dialysis need (no dialysis: 113.06 +/- 299.61ng/ml, n = 303; need for dialysis: 613.07 +/- 700.45 ng/ml, n = 11, Mean +/- SD, p < 0.001), death (no death during follow-up: 121.41 +/- 324.45 ng/ml, n = 306; death during follow-up: 522.01 +/- 521.86 ng/ml, n = 8; Mean +/- SD, p < 0.003) and MARE (no MARE: 112.08 +/- 302.00ng/ml, n = 298; MARE: 506.16 +/- 624.61 ng/ml, n = 16, Mean +/- SD, p < 0.001) during the follow-up of 90 days after contrast media exposure. Correction of urine VDBP concentrations for creatinine excretion confirmed its predictive value and was consistent with increased levels of urinary Kidney Injury Molecule1 (KIM-1) and baseline plasma creatinine in patients with above mentioned complications. The impact of urinary VDBP and KIM-1 on MARE was independent of known CIN risk factors such as anemia, preexisting renal failure, preexisting heart failure, and diabetes. Conclusions Urinary VDBP is a promising novel biomarker of major contrast induced nephropathy-associated events 90 days after contrast media exposure. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 558 KW - acute kidney injury KW - cardiac surgery KW - molecule-1 KIM-1 KW - early diagnosis KW - failure KW - intervention KW - disease KW - NGAL Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-411928 SN - 1866-8372 IS - 558 ER - TY - JOUR A1 - Chaykovska, Lyubov A1 - Heunisch, Fabian A1 - von Einem, Gina A1 - Alter, Markus L. A1 - Hocher, Carl-Friedrich A1 - Tsuprykov, Oleg A1 - Dschietzig, Thomas A1 - Kretschmer, Axel A1 - Hocher, Berthold T1 - Urinary Vitamin D Binding Protein and KIM-1 Are Potent New Biomarkers of Major Adverse Renal Events in Patients Undergoing Coronary Angiography JF - PLoS one N2 - Background Vitamin-D-binding protein (VDBP) is a low molecular weight protein that is filtered through the glomerulus as a 25-(OH) vitamin D 3/VDBP complex. In the normal kidney VDBP is reabsorbed and catabolized by proximal tubule epithelial cells reducing the urinary excretion to trace amounts. Acute tubular injury is expected to result in urinary VDBP loss. The purpose of our study was to explore the potential role of urinary VDBP as a biomarker of an acute renal damage. Method We included 314 patients with diabetes mellitus or mild renal impairment undergoing coronary angiography and collected blood and urine before and 24 hours after the CM application. Patients were followed for 90 days for the composite endpoint major adverse renal events (MARE: need for dialysis, doubling of serum creatinine after 90 days, unplanned emergency rehospitalization or death). Results Increased urine VDBP concentration 24 hours after contrast media exposure was predictive for dialysis need (no dialysis: 113.06 +/- 299.61ng/ml, n = 303; need for dialysis: 613.07 +/- 700.45 ng/ml, n = 11, Mean +/- SD, p < 0.001), death (no death during follow-up: 121.41 +/- 324.45 ng/ml, n = 306; death during follow-up: 522.01 +/- 521.86 ng/ml, n = 8; Mean +/- SD, p < 0.003) and MARE (no MARE: 112.08 +/- 302.00ng/ml, n = 298; MARE: 506.16 +/- 624.61 ng/ml, n = 16, Mean +/- SD, p < 0.001) during the follow-up of 90 days after contrast media exposure. Correction of urine VDBP concentrations for creatinine excretion confirmed its predictive value and was consistent with increased levels of urinary Kidney Injury Molecule1 (KIM-1) and baseline plasma creatinine in patients with above mentioned complications. The impact of urinary VDBP and KIM-1 on MARE was independent of known CIN risk factors such as anemia, preexisting renal failure, preexisting heart failure, and diabetes. Conclusions Urinary VDBP is a promising novel biomarker of major contrast induced nephropathy-associated events 90 days after contrast media exposure. Y1 - 2016 U6 - https://doi.org/10.1371/journal.pone.0145723 SN - 1932-6203 VL - 11 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Archambault, S. A1 - Archer, A. A1 - Benbow, W. A1 - Bird, R. A1 - Biteau, Jonathan A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Byrum, K. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Ciupik, L. A1 - Connolly, M. P. A1 - Cui, W. A1 - Eisch, J. D. A1 - Errando, M. A1 - Falcone, A. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Gyuk, G. A1 - Huetten, M. A1 - Hakansson, Nils A1 - Hanna, D. A1 - Holder, J. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Meagher, K. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nguyen, T. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Perkins, J. S. A1 - Pichel, A. A1 - Pohl, Martin A1 - Popkow, A. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Rovero, A. C. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Williams, D. A. A1 - Zitzer, B. A1 - Fumagalli, M. A1 - Prochaska, J. X. T1 - UPPER LIMITS FROM FIVE YEARS OF BLAZAR OBSERVATIONS WITH THE VERITAS CHERENKOV TELESCOPES JF - The astronomical journal N2 - Between the beginning of its full-scale scientific operations in 2007 and 2012, the VERITAS Cherenkov telescope array observed more than 130 blazars; of these, 26 were detected as very-high-energy (VHE; E > 100 GeV) gamma-ray sources. In this work, we present the analysis results of a sample of 114 undetected objects. The observations constitute a total live-time of similar to 570 hr. The sample includes several unidentified Fermi-Large Area Telescope (LAT) sources (located at high Galactic latitude) as well as all the sources from the second Fermi-LAT catalog that are contained within the field of view of the VERITAS observations. We have also performed optical spectroscopy measurements in order to estimate the redshift of some of these blazars that do not have spectroscopic distance estimates. We present new optical spectra from the Kast instrument on the Shane telescope at the Lick observatory for 18 blazars included in this work, which allowed for the successful measurement or constraint on the redshift of four of them. For each of the blazars included in our sample, we provide the flux upper limit in the VERITAS energy band. We also study the properties of the significance distributions and we present the result of a stacked analysis of the data set, which shows a 4s excess. KW - BL Lacertae objects: general KW - galaxies: active KW - gamma rays: galaxies KW - radiation mechanisms: non-thermal Y1 - 2016 U6 - https://doi.org/10.3847/0004-6256/151/6/142 SN - 0004-6256 SN - 1538-3881 VL - 151 PB - IOP Publ. Ltd. CY - Bristol ER - TY - THES A1 - Klier, Dennis Tobias T1 - Upconversion luminescence in Er-codoped NaYF4 nanoparticles T1 - Frequenzaufkonversion in Er-codotierten NaYF4 Nanopartikeln BT - fundamental photophysics and optimization for life science applications BT - fundamentale Photophysik und Optimierung für Anwendungen in den Lebenswissenschaften N2 - In the context of an increasing population of aging people and a shift of medical paradigm towards an individualized medicine in health care, nanostructured lanthanides doped sodium yttrium fluoride (NaYF4) represents an exciting class of upconversion nanomaterials (UCNM) which are suitable to bring forward developments in biomedicine and -biodetection. Despite the fact that among various fluoride based upconversion (UC) phosphors lanthanide doped NaYF4 is one of the most studied upconversion nanomaterial, many open questions are still remaining concerning the interplay of the population routes of sensitizer and activator electronic states involved in different luminescence upconversion photophysics as well as the role of phonon coupling. The collective work aims to explore a detailed understanding of the upconversion mechanism in nanoscaled NaYF4 based materials co-doped with several lanthanides, e.g. Yb3+ and Er3+ as the "standard" type upconversion nanoparticles (UCNP) up to advanced UCNP with Gd3+ and Nd3+. Especially the impact of the crystal lattice structure as well as the resulting lattice phonons on the upconversion luminescence was investigated in detail based on different mixtures of cubic and hexagonal NaYF4 nanoscaled crystals. Three synthesis methods, depending on the attempt of the respective central spectroscopic questions, could be accomplished in the following work. NaYF4 based upconversion nanoparticles doped with several combination of lanthanides (Yb3+, Er3+, Gd3+ and Nd3+) were synthesized successfully using a hydrothermal synthesis method under mild conditions as well as a co-precipitation and a high temperature co-precipitation technique. Structural information were gathered by means of X-ray diffraction (XRD), electron microscopy (TEM), dynamic light scattering (DLS), Raman spectroscopy and inductively coupled plasma atomic emission spectrometry (ICP-OES). The results were discussed in detail with relation to the spectroscopic results. A variable spectroscopic setup was developed for multi parameter upconversion luminescence studies at various temperature 4 K to 328 K. Especially, the study of the thermal behavior of upconversion luminescence as well as time resolved area normalized emission spectra were a prerequisite for the detailed understanding of intramolecular deactivation processes, structural changes upon annealing or Gd3+ concentration, and the role of phonon coupling for the upconversion efficiency. Subsequently it became possible to synthesize UCNP with tailored upconversion luminescence properties. In the end, the potential of UCNP for life science application should be enunciated in context of current needs and improvements of a nanomaterial based optical sensors, whereas the "standard" UCNP design was attuned according to the special conditions in the biological matrix. In terms of a better biocompatibility due to a lower impact on biological tissue and higher penetrability for the excitation light. The first step into this direction was to use Nd3+ ions as a new sensitizer in tridoped NaYF4 based UCNP, whereas the achieved absolute and relative temperature sensitivity is comparable to other types of local temperature sensors in the literature. N2 - Ziel der Arbeit war es ein erweitertes Verständnis des Mechanismus der Lichtaufkonversion, sowie dessen gezielte Manipulation in verschiedenen Nanomaterialien auf Natriumyttrium-fluoridbasis zu erlangen. Die optischen Eigenschaften werden dabei durch eine gezielte Zusammenstellung verschiedener Lanthanoidionen hervorgerufen, welche während der Synthese in die Materialien eingebracht werden. Der Fokus lag hierbei in der Aufklärung des Zusammenspiels zwischen der Struktur der Materialien und deren Lichtaufkonver-sionsvermögen sowie dem Erlangen eines generellen Verständnisses der einzelnen Teilschritte des Lichtaufkonversionsmechanismus. Dabei wird das Licht, welches nach Anregung der Lanthanoidionen durch einen Laser von diesen emittiert wird, hinsichtlich der Farbzusammensetzung und des Abklingverhaltens der Lumineszenz untersucht. Diese Erkenntnisse geben sowohl einen Einblick in die verschiedenen Teilschritte des Lichtaufkonversionsmechanismus, als auch deren Korrelation zur Struktur der Nanomaterialien. Während der Arbeit wurde ein variabler Messplatz mit einer wellenlängendurchstimmbaren Anregungslichtquelle, einer Detektionseinheit mit hervorragender spektraler und zeitlicher Auflösung für die Messung des emittierten Lichtes sowie einer Temperiereinheit, mit der die Proben in einem Temperaturbereich von 4 Kelvin (-269,15 °C) bis 328 Kelvin (50 °C) temperiert werden können, aufgebaut. Die Proben wurden mithilfe der modernen Kopräzipitations- und Hydrothermalsynthese in verschiedenen Zusammensetzungen und Oberflächenmodifizierungen hergestellt, um sowohl Partikel für fundamentale Untersuchungen der Lichtaufkonversion verfügbar zu haben, als auch den hohen Anforderungen für Anwendungen in den Lebenswissenschaften gerecht zu werden. Die Reaktion fand bei hohen Temperaturen (160 °C bis 320 °C) unter Schutzgasatmosphäre statt und gewährleistete so die Bildung von hochkristallinen Partikeln, deren Größe stark mit der Synthesetemperatur korreliert. Mithilfe von zeitaufgelösten Lumineszenzuntersuchungen gelang ein sehr detaillierter Einblick in strukturelle Veränderungen der Nanopartikeln, welche durch klassische strukturanalytische Methoden, wie der Röntgenpulverdiffraktometrie, nicht in dem Maße möglich sind. Zudem konnte ein erheblicher Teil dazu beigetragen werden, das komplexe Zusammenspiel von Energietransportmechanismen, Gitterschwingungen und thermisch induzierten Prozessen zu verstehen. Zuletzt wurden, basierend auf der Vielzahl an gewonnenen Erkenntnissen, speziell designte Nanopartikel hergestellt. Die Farbe des Emissionslichts dieser Partikel wies dabei eine hohe Abhängigkeit von der Umgebungstemperatur auf. Auftretende Herausforderungen induziert durch das verwendete Anregungslicht im Nahinfrarotenbereich, wie das Aufheizen oder die zu hohe Absorption der Probe, wurden durch die Erweiterung des Aufkonversionssystems gelöst. Damit konnten beste Voraussetzungen für potentielle Anwendungen, wie zum Beispiel als Nanothermometer geschaffen werden. KW - Nanopartikel KW - nanoparticle KW - Frequenzaufkonversion KW - upconversion KW - Lanthanoide KW - lanthanides Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-98486 ER - TY - THES A1 - Shahnejat-Bushehri, Sara T1 - Unravelling the role of the Arabidopsis NAC transcription factor JUNGBRUNNEN1 (JUB1) for the regulation of growth and stress responses Y1 - 2016 ER - TY - JOUR A1 - Ambrasat, Jens A1 - von Scheve, Christian A1 - Schauenburg, Gesche A1 - Conrad, Markus A1 - Schröder, Tobias T1 - Unpacking the Habitus: Meaning Making Across Lifestyles JF - Sociological Forum KW - cognition KW - culture KW - habitus KW - identity KW - lifestyles KW - stratification Y1 - 2016 U6 - https://doi.org/10.1111/socf.12293 SN - 0884-8971 SN - 1573-7861 VL - 31 SP - 994 EP - 1017 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Godec, Aljaz A1 - Metzler, Ralf T1 - Universal Proximity Effect in Target Search Kinetics in the Few-Encounter Limit JF - Physical review : X, Expanding access N2 - When does a diffusing particle reach its target for the first time? This first-passage time (FPT) problem is central to the kinetics of molecular reactions in chemistry and molecular biology. Here, we explain the behavior of smooth FPT densities, for which all moments are finite, and demonstrate universal yet generally non-Poissonian long-time asymptotics for a broad variety of transport processes. While Poisson-like asymptotics arise generically in the presence of an effective repulsion in the immediate vicinity of the target, a time-scale separation between direct and reflected indirect trajectories gives rise to a universal proximity effect: Direct paths, heading more or less straight from the point of release to the target, become typical and focused, with a narrow spread of the corresponding first-passage times. Conversely, statistically dominant indirect paths exploring the entire system tend to be massively dissimilar. The initial distance to the target particularly impacts gene regulatory or competitive stochastic processes, for which few binding events often determine the regulatory outcome. The proximity effect is independent of details of the transport, highlighting the robust character of the FPT features uncovered here. Y1 - 2016 U6 - https://doi.org/10.1103/PhysRevX.6.041037 SN - 2160-3308 VL - 6 PB - American Physical Society CY - College Park ER - TY - GEN A1 - Farhy, Yael A1 - Veríssimo, Joao Marques A1 - Clahsen, Harald T1 - Universal and particular in morphological processing BT - evidence from Hebrew T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Do properties of individual languages shape the mechanisms by which they are processed? By virtue of their non-concatenative morphological structure, the recognition of complex words in Semitic languages has been argued to rely strongly on morphological information and on decomposition into root and pattern constituents. Here, we report results from a masked priming experiment in Hebrew in which we contrasted verb forms belonging to two morphological classes, Paal and Piel, which display similar properties, but crucially differ on whether they are extended to novel verbs. Verbs from the open-class Piel elicited familiar root priming effects, but verbs from the closed-class Paal did not. Our findings indicate that, similarly to other (e.g., Indo-European) languages, down-to-the-root decomposition in Hebrew does not apply to stems of non-productive verbal classes. We conclude that the Semitic word processor is less unique than previously thought: Although it operates on morphological units that are combined in a non-linear way, it engages the same universal mechanisms of storage and computation as those seen in other languages. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 468 KW - language universals KW - morphology KW - priming KW - Semitic Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-412541 EP - 468 ER - TY - JOUR A1 - Veríssimo, Joao Marques A1 - Farhy, Yael A1 - Clahsen, Harald T1 - Universal and particular in morphological processing BT - Evidence from Hebrew JF - Quarterly Journal of Experimental Psychology N2 - Do properties of individual languages shape the mechanisms by which they are processed? By virtue of their nonconcatenative morphological structure, the recognition of complex words in Semitic languages has been argued to rely strongly on morphological information and on decomposition into root and pattern constituents. Here, we report results from a masked priming experiment in Hebrew in which we contrasted verb forms belonging to two morphological classes, Paal and Piel, which display similar properties, but crucially differ on whether they are extended to novel verbs. Verbs from the open-class Piel elicited familiar root priming effects, but verbs from the closed-class Paal did not. Our findings indicate that, similarly to other (e.g., Indo-European) languages, down-to-the-root decomposition in Hebrew does not apply to stems of non-productive verbal classes. We conclude that the Semitic word processor is less unique than previously thought: Although it operates on morphological units that are combined in a non-linear way, it engages the same universal mechanisms of storage and computation as those seen in other languages. KW - Language universals , morphology , priming , Semitic Y1 - 2018 UR - http://journals.sagepub.com/doi/pdf/10.1080/17470218.2017.1310917 U6 - https://doi.org/10.1080/17470218.2017.1310917 VL - 71 IS - 5 SP - 1125 EP - 1132 ER - TY - JOUR A1 - Wolff, Wanja A1 - Schindler, Sebastian A1 - Englert, Christoph A1 - Brand, Ralf A1 - Kissler, Johanna T1 - Uninstructed BIAT faking when ego depleted or in normal state: differential effect on brain and behavior JF - BMC neuroscience N2 - Background: Deception can distort psychological tests on socially sensitive topics. Understanding the cerebral processes that are involved in such faking can be useful in detection and prevention of deception. Previous research shows that faking a brief implicit association test (BIAT) evokes a characteristic ERP response. It is not yet known whether temporarily available self-control resources moderate this response. We randomly assigned 22 participants (15 females, 24.23 +/- 2.91 years old) to a counterbalanced repeated-measurements design. Participants first completed a Brief-IAT (BIAT) on doping attitudes as a baseline measure and were then instructed to fake a negative doping attitude both when self-control resources were depleted and non-depleted. Cerebral activity during BIAT performance was assessed using high-density EEG. Conclusions: Results indicate that temporarily available self-control resources do not affect overt faking success on a BIAT. However, differences were found on an electrophysiological level. This indicates that while on a phenotypical level self-control resources play a negligible role in deliberate test faking the underlying cerebral processes are markedly different. KW - EEG/ERP KW - Implicit association test (IAT) KW - Faking KW - Deception KW - Ego depletion KW - Cognitive control Y1 - 2016 U6 - https://doi.org/10.1186/s12868-016-0249-8 SN - 1471-2202 VL - 17 PB - BioMed Central CY - London ER - TY - GEN A1 - Wolff, Wanja A1 - Schindler, Sebastian A1 - Englert, Christoph A1 - Brand, Ralf A1 - Kissler, Johanna T1 - Uninstructed BIAT faking when ego depleted or in normal state BT - differential effect on brain and behavior T2 - BMC neuroscience N2 - Background: Deception can distort psychological tests on socially sensitive topics. Understanding the cerebral processes that are involved in such faking can be useful in detection and prevention of deception. Previous research shows that faking a brief implicit association test (BIAT ) evokes a characteristic ERP response. It is not yet known whether temporarily available self-control resources moderate this response. We randomly assigned 22 participants (15 females, 24.23 ± 2.91 years old) to a counterbalanced repeated-measurements design. Participants first com- pleted a Brief-IAT (BIAT ) on doping attitudes as a baseline measure and were then instructed to fake a negative dop - ing attitude both when self-control resources were depleted and non-depleted. Cerebral activity during BIAT perfor - mance was assessed using high-density EEG. Results: Compared to the baseline BIAT, event-related potentials showed a first interaction at the parietal P1, while significant post hoc differences were found only at the later occurring late positive potential. Here, signifi- cantly decreased amplitudes were recorded for ‘normal’ faking, but not in the depletion condition. In source space, enhanced activity was found for ‘normal’ faking in the bilateral temporoparietal junction. Behaviorally, participants were successful in faking the BIAT successfully in both conditions. Conclusions: Results indicate that temporarily available self-control resources do not affect overt faking success on a BIAT. However, differences were found on an electrophysiological level. This indicates that while on a phenotypical level self-control resources play a negligible role in deliberate test faking the underlying cerebral processes are markedly different. KW - EEG/ERP KW - implicit association test (IAT) KW - faking KW - deception KW - ego depletion KW - cognitive control Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-407342 ER - TY - JOUR A1 - Logacev, Pavel A1 - Vasishth, Shravan T1 - Understanding underspecification: A comparison of two computational implementations JF - The quarterly journal of experimental psychology N2 - Swets et al. (2008. Underspecification of syntactic ambiguities: Evidence from self-paced reading. Memory and Cognition, 36(1), 201–216) presented evidence that the so-called ambiguity advantage [Traxler et al. (1998 Traxler, M. J., Pickering, M. J., & Clifton, C. (1998). Adjunct attachment is not a form of lexical ambiguity resolution. Journal of Memory and Language, 39(4), 558–592. doi: 10.1006/jmla.1998.2600[CrossRef], [Web of Science ®], [Google Scholar]). Adjunct attachment is not a form of lexical ambiguity resolution. Journal of Memory and Language, 39(4), 558–592], which has been explained in terms of the Unrestricted Race Model, can equally well be explained by assuming underspecification in ambiguous conditions driven by task-demands. Specifically, if comprehension questions require that ambiguities be resolved, the parser tends to make an attachment: when questions are about superficial aspects of the target sentence, readers tend to pursue an underspecification strategy. It is reasonable to assume that individual differences in strategy will play a significant role in the application of such strategies, so that studying average behaviour may not be informative. In order to study the predictions of the good-enough processing theory, we implemented two versions of underspecification: the partial specification model (PSM), which is an implementation of the Swets et al. proposal, and a more parsimonious version, the non-specification model (NSM). We evaluate the relative fit of these two kinds of underspecification to Swets et al.’s data; as a baseline, we also fitted three models that assume no underspecification. We find that a model without underspecification provides a somewhat better fit than both underspecification models, while the NSM model provides a better fit than the PSM. We interpret the results as lack of unambiguous evidence in favour of underspecification; however, given that there is considerable existing evidence for good-enough processing in the literature, it is reasonable to assume that some underspecification might occur. Under this assumption, the results can be interpreted as tentative evidence for NSM over PSM. More generally, our work provides a method for choosing between models of real-time processes in sentence comprehension that make qualitative predictions about the relationship between several dependent variables. We believe that sentence processing research will greatly benefit from a wider use of such methods. KW - Computational modelling KW - Underspecification KW - Shallow processing Y1 - 2016 U6 - https://doi.org/10.1080/17470218.2015.1134602 SN - 1747-0218 SN - 1747-0226 VL - 69 SP - 996 EP - 1012 PB - BioMed Central CY - Abingdon ER - TY - GEN A1 - Logačev, Pavel A1 - Vasishth, Shravan T1 - Understanding underspecification BT - A comparison of two computational implementations N2 - Swets et al. (2008. Underspecification of syntactic ambiguities: Evidence from self-paced reading. Memory and Cognition, 36(1), 201–216) presented evidence that the so-called ambiguity advantage [Traxler et al. (1998). Adjunct attachment is not a form of lexical ambiguity resolution. Journal of Memory and Language, 39(4), 558–592], which has been explained in terms of the Unrestricted Race Model, can equally well be explained by assuming underspecification in ambiguous conditions driven by task-demands. Specifically, if comprehension questions require that ambiguities be resolved, the parser tends to make an attachment: when questions are about superficial aspects of the target sentence, readers tend to pursue an underspecification strategy. It is reasonable to assume that individual differences in strategy will play a significant role in the application of such strategies, so that studying average behaviour may not be informative. In order to study the predictions of the good-enough processing theory, we implemented two versions of underspecification: the partial specification model (PSM), which is an implementation of the Swets et al. proposal, and a more parsimonious version, the non-specification model (NSM). We evaluate the relative fit of these two kinds of underspecification to Swets et al.’s data; as a baseline, we also fitted three models that assume no underspecification. We find that a model without underspecification provides a somewhat better fit than both underspecification models, while the NSM model provides a better fit than the PSM. We interpret the results as lack of unambiguous evidence in favour of underspecification; however, given that there is considerable existing evidence for good-enough processing in the literature, it is reasonable to assume that some underspecification might occur. Under this assumption, the results can be interpreted as tentative evidence for NSM over PSM. More generally, our work provides a method for choosing between models of real-time processes in sentence comprehension that make qualitative predictions about the relationship between several dependent variables. We believe that sentence processing research will greatly benefit from a wider use of such methods. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 295 KW - Computational modelling KW - Underspecification KW - Shallow processing Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-93441 SP - 996 EP - 1012 ER - TY - THES A1 - Olen, Stephanie M. T1 - Understanding Himalayan denudation at the catchment and orogen scale T1 - Verständnis von Denudation auf regionalem und orogenem Maßstab im Himalaja N2 - Understanding the rates and processes of denudation is key to unraveling the dynamic processes that shape active orogens. This includes decoding the roles of tectonic and climate-driven processes in the long-term evolution of high- mountain landscapes in regions with pronounced tectonic activity and steep climatic and surface-process gradients. Well-constrained denudation rates can be used to address a wide range of geologic problems. In steady-state landscapes, denudation rates are argued to be proportional to tectonic or isostatic uplift rates and provide valuable insight into the tectonic regimes underlying surface denudation. The use of denudation rates based on terrestrial cosmogenic nuclide (TCN) such as 10Beryllium has become a widely-used method to quantify catchment-mean denudation rates. Because such measurements are averaged over timescales of 102 to 105 years, they are not as susceptible to stochastic changes as shorter-term denudation rate estimates (e.g., from suspended sediment measurements) and are therefore considered more reliable for a comparison to long-term processes that operate on geologic timescales. However, the impact of various climatic, biotic, and surface processes on 10Be concentrations and the resultant denudation rates remains unclear and is subject to ongoing discussion. In this thesis, I explore the interaction of climate, the biosphere, topography, and geology in forcing and modulating denudation rates on catchment to orogen scales. There are many processes in highly dynamic active orogens that may effect 10Be concentrations in modern river sands and therefore impact 10Be-derived denudation rates. The calculation of denudation rates from 10Be concentrations, however, requires a suite of simplifying assumptions that may not be valid or applicable in many orogens. I investigate how these processes affect 10Be concentrations in the Arun Valley of Eastern Nepal using 34 new 10Be measurements from the main stem Arun River and its tributaries. The Arun Valley is characterized by steep gradients in climate and topography, with elevations ranging from <100 m asl in the foreland basin to >8,000 asl in the high sectors to the north. This is coupled with a five-fold increase in mean annual rainfall across strike of the orogen. Denudation rates from tributary samples increase toward the core of the orogen, from <0.2 to >5 mm/yr from the Lesser to Higher Himalaya. Very high denudation rates (>2 mm/yr), however, are likely the result of 10Be TCN dilution by surface and climatic processes, such as large landsliding and glaciation, and thus may not be representative of long-term denudation rates. Mainstem Arun denudation rates increase downstream from ~0.2 mm/yr at the border with Tibet to 0.91 mm/yr at its outlet into the Sapt Kosi. However, the downstream 10Be concentrations may not be representative of the entire upstream catchment. Instead, I document evidence for downstream fining of grains from the Tibetan Plateau, resulting in an order-of-magnitude apparent decrease in the measured 10Be concentration. In the Arun Valley and across the Himalaya, topography, climate, and vegetation are strongly interrelated. The observed increase in denudation rates at the transition from the Lesser to Higher Himalaya corresponds to abrupt increases in elevation, hillslope gradient, and mean annual rainfall. Thus, across strike (N-S), it is difficult to decipher the potential impacts of climate and vegetation cover on denudation rates. To further evaluate these relationships I instead took advantage of an along-strike west-to-east increase of mean annual rainfall and vegetation density in the Himalaya. An analysis of 136 published 10Be denudation rates from along strike of the revealed that median denudation rates do not vary considerably along strike of the Himalaya, ~1500 km E-W. However, the range of denudation rates generally decreases from west to east, with more variable denudation rates in the northwestern regions of the orogen than in the eastern regions. This denudation rate variability decreases as vegetation density increases (R=- 0.90), and increases proportionately to the annual seasonality of vegetation (R=0.99). Moreover, rainfall and vegetation modulate the relationship between topographic steepness and denudation rates such that in the wet, densely vegetated regions of the Himalaya, topography responds more linearly to changes in denudation rates than in dry, sparsely vegetated regions, where the response of topographic steepness to denudation rates is highly nonlinear. Understanding the relationships between denudation rates, topography, and climate is also critical for interpreting sedimentary archives. However, there is a lack of understanding of how terrestrial organic matter is transported out of orogens and into sedimentary archives. Plant wax lipid biomarkers derived from terrestrial and marine sedimentary records are commonly used as paleo- hydrologic proxy to help elucidate these problems. I address the issue of how to interpret the biomarker record by using the plant wax isotopic composition of modern suspended and riverbank organic matter to identify and quantify organic matter source regions in the Arun Valley. Topographic and geomorphic analysis, provided by the 10Be catchment-mean denudation rates, reveals that a combination of topographic steepness (as a proxy for denudation) and vegetation density is required to capture organic matter sourcing in the Arun River. My studies highlight the importance of a rigorous and careful interpretation of denudation rates in tectonically active orogens that are furthermore characterized by strong climatic and biotic gradients. Unambiguous information about these issues is critical for correctly decoding and interpreting the possible tectonic and climatic forces that drive erosion and denudation, and the manifestation of the erosion products in sedimentary archives. N2 - Schlüssel im Verständnis der dynamischen Prozesse in aktiven Orogenen ist die Kenntnis der Abtragungsraten und -prozesse. Eine breite Auswahl geologischer Fragen können mit well-constrained Abtragungsraten erörtert werden. Sind Landschaften im Gleichgewicht so sind die Denudationsraten proportional zu den tektonischen und isostatischen Hebungsraten und geben somit wichtige Hinweise über die tektonischen Eigenschaften der Region. Eine weit verbreitete und etablierte Methode zur Bestimmung mittlerer Denudationsraten eines bestimmten Einzugsgebietes ist Beryllium-10, ein terrestrisches kosmogenes Nuklid (10Be TCN). 10Be TCN Messungen stellen durchschnittliche Abtragungsraten über einen Zeitraum von 10^2 – 10^5 Jahren dar und sind daher weniger verletzlich gegenüber stochastischen Änderungen wie Erosionsraten, die über einen kurzen Zeitraum ermittelt werden z.B. in Suspension. Sie sind daher zuverlässig einsetzbar um langfristige Prozesse zu vergleichen. Allerdings ist unklar welche Einfluss verschiedene klimatische, biologische oder erdoberflächen Prozesse auf die 10Be Konzentration ausüben und somit auch auf die resultierenden Abtragungsraten. In dieser Doktorarbeit, setze ich mich mit dem Zwischenspiel von Klima, Biosphäre, Topographie und Geologie auseinander und dem Einfluss, den sie auf Abtragungsraten ausüben sowohl auf regionalem wie auch auf orogenem Maßstab. In hoch dynamischen aktiven Gebirgen gibt es viele Prozesse, welche die 10Be Konzentration in heutigen Flusssanden beeinflussen und damit auch die, mittels 10Be berechneten, Abtragungsraten. Um diese Raten mittels 10Be Konzentrationen zu berechnen benötigen wir einige vereinfachende Annahmen, die möglicherweise in anderen Regionen keine Gültigkeit haben. Ich untersuche den Einfluss dieser Prozesse auf die 10Be Konzentration. Dazu haben wir im Arun Tal im Osten Nepals 34 neue 10Be Konzentrationen des Arun Flusses und seinen Zuflüssen untersucht. Charakteristisch für das Arun Tal sind die steilen Gradienten im Klima mit einem fünffachen Anstieg des mittleren jährlichen Regenfalls über das Orogens, und in der Topographie mit Höhen von weniger als 100 m über Meer im Vorlandbecken bis über 8000 m über Meer im Gebirge. Die Abtragungsraten der Proben der Zuflüsse nehmen gegen das Zentrum des Gebirges von weniger <0.2 zu mehr als >5 mm/yr zu d.h. ansteigend vom Lesser zum Higher Himalaya. Sehr hohe Denudationsraten (> 2mm/yr) können durch erdoberflächen und klimatische Prozesse verwässert werden z. B. grosse Erdrutsche und Vergletscherungen, und sind daher nicht unbedingt repräsentativ für langzeitliche Abtragungsraten. Im Arun nehmen die Raten des Hauptflusses flussabwärts von 0.2 mm/yr im Bereich der Grenze zu Tibet auf 0.91 mm/yr am Ausfluss in Sapt Kosi zu. Es ist möglich, dass diese 10Be Konzentrationen nicht das vollständige flussauswärtsliegende Einzugsgebiet repräsentieren. Stattdessen lege ich dar wie sich die Korngrösse ab dem tibetischen Plateau verfeinert und dazu führt, dass die 10Be Konzentrationen offenkundig im Bereich einer Grössenordnung abnehmen. Im Arun Tal und sowie über den ganzen Himalaja sind Topographie, Klima und Vegetation sehr stark miteinander verbunden. Das Ansteigen der Denudationsraten im Übergang vom Lesser zum Higher Himalaya stimmt mit dem abrupten Ansteigen der Höhe, des Hangneigungsgradienten und des mittleren jährlichen Regenfalles überein. Es ist schwierig die möglichen Einflüssen von Klima und der Vegetationsdichte auf die Abtragungsraten über das Orogen hinweg (N-S) zu entziffern. Stattdessen, nutzen wir den Vorteil der, von West nach Ost, parallel zum Himalaja verlaufenden, Zunahme des mittleren jährlichen Regenfalles und der Vegetationsdichte. Eine Analyse 136 publizierter 10Be TCN Abtragungsraten entlang des Gebirges, zeigt dass die im Streichen liegenden mittleren Denudationsraten (ca. 1500 km Ost-West) nicht deutlich variieren. Generell sinkt die Wertebereich der Denudationsraten vom Westen gegen Osten, wobei in den nordwestlichen Regionen des Himalajas variablere Abtragungsraten vorherrschen als in den östlichen Regionen. Diese Vielfalt in den Denudationsraten sinkt mit steigender Vegetationsdichte (R=-0.90) und steigt proportional zur (jährlichen) Saisonalität der Vegetation (R=0.99). Vielmehr noch wird das Verhältnis zwischen der topographischen Steilheit und den Abtragungsraten durch Regen und Vegetation beeinflusst z. B. in feuchten Gebieten mit starker Vegetation reagiert die Topographie linearer auf Wechsel in den Abtragungsraten als in trockenen, kaum bewachsenen Regionen, wo die Reaktion der topographischen Steilheit auf die Denudationsraten äusserst nicht-linear ist. Das Verständnis der Beziehung zwischen Erosion, Topographie und Klima ist auch entscheidend für die Interpretation von Sedimentarchiven. Unser Wissen über die Repräsentativität von terrestrisches organisches Material, abgelagert in z.B. Flussdeltas, für die Einzugsgebiete der entsprechenden Flüsse, ist nach wie vor nur vage. Dennoch sind Blattwachse höherer Landpflanzen, extrahiert aus terrestrischen und marinen Sedimenten, ein häufig verwendeter paläohydrologischer Proxy. Im Rahmen dieser Arbeit nutzen wir die Isotopenzusammensetzung von Pflanzenwachsen aus Suspensionsmaterial und aus Flusssedimenten als Herkunftsmarker und zur Quantifizierung des organischen Materials im Arun Tal. Die Analyse von Vegetationsdichte und Regenverteilung in Kombination mit Abtragungsraten des Einzugsgebietes, welche durch die mittleren 10Be-Erosionsraten gestützt werden, zeigen, dass das Vorhandensein dichter Vegetation ein zwar notwendiges, aber nicht hinreichendes Kriterium für hohen OM-Export ist. Vielmehr können wir zeigen, dass nur eine Kombination aus dichter Vegetationsdecke und Erosion zu hohem OM-Export führt. Für die Interpretation entspechender Archive bedeutet das, dass sie im Wesentlichen jene Bereiche des Einzugsgebietes repräsentieren, welche durch hohe Pflanzendichte und starke Erosion charakterisiert sind. Diese Studien belegen wie wichtig es ist die Abtragungsraten in aktiven Gebirgen umfassend zu verstehen. Für die Interpretation kann dieses Verständnis der möglichen tektonischen und klimatischen Gewalten, welche Erosion und Abtragung steuern, und auch das Verständnis der Sedimentarchive aus den Gebirgen stammend, entscheidend sein. KW - geology KW - geomorphology KW - Himalaya KW - Geologie KW - Geomorphologie KW - Himalaja Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-91423 ER - TY - JOUR A1 - Bodrova, Anna S. A1 - Chechkin, Aleksei V. A1 - Cherstvy, Andrey G. A1 - Safdari, Hadiseh A1 - Sokolov, Igor M. A1 - Metzler, Ralf T1 - Underdamped scaled Brownian motion: (non-)existence of the overdamped limit in anomalous diffusion JF - Scientific reports N2 - It is quite generally assumed that the overdamped Langevin equation provides a quantitative description of the dynamics of a classical Brownian particle in the long time limit. We establish and investigate a paradigm anomalous diffusion process governed by an underdamped Langevin equation with an explicit time dependence of the system temperature and thus the diffusion and damping coefficients. We show that for this underdamped scaled Brownian motion (UDSBM) the overdamped limit fails to describe the long time behaviour of the system and may practically even not exist at all for a certain range of the parameter values. Thus persistent inertial effects play a non-negligible role even at significantly long times. From this study a general questions on the applicability of the overdamped limit to describe the long time motion of an anomalously diffusing particle arises, with profound consequences for the relevance of overdamped anomalous diffusion models. We elucidate our results in view of analytical and simulations results for the anomalous diffusion of particles in free cooling granular gases. Y1 - 2016 U6 - https://doi.org/10.1038/srep30520 SN - 2045-2322 VL - 6 PB - Nature Publ. Group CY - London ER - TY - GEN A1 - Bodrova, Anna S. A1 - Chechkin, Aleksei V. A1 - Cherstvy, Andrey G. A1 - Safdari, Hadiseh A1 - Sokolov, Igor M. A1 - Metzler, Ralf T1 - Underdamped scaled Brownian motion BT - (non-)existence of the overdamped limit in anomalous diffusion N2 - It is quite generally assumed that the overdamped Langevin equation provides a quantitative description of the dynamics of a classical Brownian particle in the long time limit. We establish and investigate a paradigm anomalous diffusion process governed by an underdamped Langevin equation with an explicit time dependence of the system temperature and thus the diffusion and damping coefficients. We show that for this underdamped scaled Brownian motion (UDSBM) the overdamped limit fails to describe the long time behaviour of the system and may practically even not exist at all for a certain range of the parameter values. Thus persistent inertial effects play a non-negligible role even at significantly long times. From this study a general questions on the applicability of the overdamped limit to describe the long time motion of an anomalously diffusing particle arises, with profound consequences for the relevance of overdamped anomalous diffusion models. We elucidate our results in view of analytical and simulations results for the anomalous diffusion of particles in free cooling granular gases. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 267 Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-97158 ER - TY - JOUR A1 - Bodrova, Anna S. A1 - Chechkin, Aleksei V. A1 - Cherstvy, Andrey G. A1 - Safdari, Hadiseh A1 - Sokolov, Igor M. A1 - Metzler, Ralf T1 - Underdamped scaled Brownian motion BT - (non-)existence of the overdamped limit in anomalous diffusion JF - Scientific reports N2 - It is quite generally assumed that the overdamped Langevin equation provides a quantitative description of the dynamics of a classical Brownian particle in the long time limit. We establish and investigate a paradigm anomalous diffusion process governed by an underdamped Langevin equation with an explicit time dependence of the system temperature and thus the diffusion and damping coefficients. We show that for this underdamped scaled Brownian motion (UDSBM) the overdamped limit fails to describe the long time behaviour of the system and may practically even not exist at all for a certain range of the parameter values. Thus persistent inertial effects play a non-negligible role even at significantly long times. From this study a general questions on the applicability of the overdamped limit to describe the long time motion of an anomalously diffusing particle arises, with profound consequences for the relevance of overdamped anomalous diffusion models. We elucidate our results in view of analytical and simulations results for the anomalous diffusion of particles in free cooling granular gases. Y1 - 2016 U6 - https://doi.org/10.1038/srep30520 SN - 2045-2322 VL - 6 PB - Nature Publishing Group CY - London ER - TY - JOUR A1 - Kashima, Eri A1 - Williams, Daniel A1 - Ellison, T. Mark A1 - Schokkin, Dineke A1 - Escudero, Paola T1 - Uncovering the acoustic vowel space of a previously undescribed language: The vowels of Nambo JF - The journal of the Acoustical Society of America N2 - This study presents the first acoustic description of the vowel space of a Papuan language—Nambo, spoken in southern Papua New Guinea—based on duration and first and second formant measurements from 19 adult male and female speakers across three age groups (young, middle-aged, senior). Phonemically, Nambo has six full vowels /i, e, æ, ɑ, o, u/ and a reduced vowel tentatively labeled /ə/. Unlike the full vowels, the quality of /ə/ showed great variation: seniors' and young females' realizations tended to be more open and retracted than those by young males, while middle-aged speakers' productions fell between these two variants. Y1 - 2016 U6 - https://doi.org/10.1121/1.4954395 SN - 0001-4966 SN - 1520-8524 VL - 139 SP - EL252 EP - EL256 PB - American Institute of Physics CY - Melville ER - TY - GEN A1 - Schwanghart, Wolfgang A1 - Worni, Raphael A1 - Huggel, Christian A1 - Stoffel, Markus A1 - Korup, Oliver T1 - Uncertainty in the Himalayan energy–water nexus BT - estimating regional exposure to glacial lake outburst floods N2 - Himalayan water resources attract a rapidly growing number of hydroelectric power projects (HPP) to satisfy Asia's soaring energy demands. Yet HPP operating or planned in steep, glacier-fed mountain rivers face hazards of glacial lake outburst floods (GLOFs) that can damage hydropower infrastructure, alter water and sediment yields, and compromise livelihoods downstream. Detailed appraisals of such GLOF hazards are limited to case studies, however, and a more comprehensive, systematic analysis remains elusive. To this end we estimate the regional exposure of 257 Himalayan HPP to GLOFs, using a flood-wave propagation model fed by Monte Carlo-derived outburst volumes of >2300 glacial lakes. We interpret the spread of thus modeled peak discharges as a predictive uncertainty that arises mainly from outburst volumes and dam-breach rates that are difficult to assess before dams fail. With 66% of sampled HPP are on potential GLOF tracks, up to one third of these HPP could experience GLOF discharges well above local design floods, as hydropower development continues to seek higher sites closer to glacial lakes. We compute that this systematic push of HPP into headwaters effectively doubles the uncertainty about GLOF peak discharge in these locations. Peak discharges farther downstream, in contrast, are easier to predict because GLOF waves attenuate rapidly. Considering this systematic pattern of regional GLOF exposure might aid the site selection of future Himalayan HPP. Our method can augment, and help to regularly update, current hazard assessments, given that global warming is likely changing the number and size of Himalayan meltwater lakes. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 266 KW - hydropower KW - water resources KW - glacial hazards KW - glacial lake outburst floods KW - Himalayas Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-97136 ER - TY - JOUR A1 - Schwanghart, Wolfgang A1 - Worni, Raphael A1 - Huggel, Christian A1 - Stoffel, Markus A1 - Korup, Oliver T1 - Uncertainty in the Himalayan energy–water nexus BT - estimating regional exposure to glacial lake outburst floods JF - Environmental research letters : ERL N2 - Himalayan water resources attract a rapidly growing number of hydroelectric power projects (HPP) to satisfy Asia's soaring energy demands. Yet HPP operating or planned in steep, glacier-fed mountain rivers face hazards of glacial lake outburst floods (GLOFs) that can damage hydropower infrastructure, alter water and sediment yields, and compromise livelihoods downstream. Detailed appraisals of such GLOF hazards are limited to case studies, however, and a more comprehensive, systematic analysis remains elusive. To this end we estimate the regional exposure of 257 Himalayan HPP to GLOFs, using a flood-wave propagation model fed by Monte Carlo-derived outburst volumes of >2300 glacial lakes. We interpret the spread of thus modeled peak discharges as a predictive uncertainty that arises mainly from outburst volumes and dam-breach rates that are difficult to assess before dams fail. With 66% of sampled HPP are on potential GLOF tracks, up to one third of these HPP could experience GLOF discharges well above local design floods, as hydropower development continues to seek higher sites closer to glacial lakes. We compute that this systematic push of HPP into headwaters effectively doubles the uncertainty about GLOF peak discharge in these locations. Peak discharges farther downstream, in contrast, are easier to predict because GLOF waves attenuate rapidly. Considering this systematic pattern of regional GLOF exposure might aid the site selection of future Himalayan HPP. Our method can augment, and help to regularly update, current hazard assessments, given that global warming is likely changing the number and size of Himalayan meltwater lakes. KW - Himalayas KW - glacial hazards KW - glacial lake outburst floods KW - hydropower KW - water resources Y1 - 2016 U6 - https://doi.org/10.1088/1748-9326/11/7/074005 SN - 1748-9326 VL - 11 PB - IOP Publ. CY - Bristol ER - TY - JOUR A1 - Schwanghart, Wolfgang A1 - Worni, Raphael A1 - Huggel, Christian A1 - Stoffel, Markus A1 - Korup, Oliver T1 - Uncertainty in the Himalayan energy-water nexus: estimating regional exposure to glacial lake outburst floods JF - Environmental research letters N2 - Himalayan water resources attract a rapidly growing number of hydroelectric power projects (HPP) to satisfy Asia's soaring energy demands. Yet HPP operating or planned in steep, glacier-fed mountain rivers face hazards of glacial lake outburst floods (GLOFs) that can damage hydropower infrastructure, alter water and sediment yields, and compromise livelihoods downstream. Detailed appraisals of such GLOF hazards are limited to case studies, however, and a more comprehensive, systematic analysis remains elusive. To this end we estimate the regional exposure of 257 Himalayan HPP to GLOFs, using a flood-wave propagation model fed by Monte Carlo-derived outburst volumes of >2300 glacial lakes. We interpret the spread of thus modeled peak discharges as a predictive uncertainty that arises mainly from outburst volumes and dam-breach rates that are difficult to assess before dams fail. With 66% of sampled HPP are on potential GLOF tracks, up to one third of these HPP could experience GLOF discharges well above local design floods, as hydropower development continues to seek higher sites closer to glacial lakes. We compute that this systematic push of HPP into headwaters effectively doubles the uncertainty about GLOF peak discharge in these locations. Peak discharges farther downstream, in contrast, are easier to predict because GLOF waves attenuate rapidly. Considering this systematic pattern of regional GLOF exposure might aid the site selection of future Himalayan HPP. Our method can augment, and help to regularly update, current hazard assessments, given that global warming is likely changing the number and size of Himalayan meltwater lakes. KW - hydropower KW - water resources KW - glacial hazards KW - glacial lake outburst floods KW - Himalayas Y1 - 2016 U6 - https://doi.org/10.1088/1748-9326/11/7/074005 SN - 1748-9326 VL - 11 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Zhang, Pengfei A1 - Behl, Marc A1 - Peng, Xingzhou A1 - Razzaq, Muhammad Yasar A1 - Lendlein, Andreas T1 - Ultrasonic Cavitation Induced Shape-Memory Effect in Porous Polymer Networks JF - Macromolecular rapid communications N2 - Inspired by the application of ultrasonic cavitation based mechanical force (CMF) to open small channels in natural soft materials (skin or tissue), it is explored whether an artificial polymer network can be created, in which shape-changes can be induced by CMF. This concept comprises an interconnected macroporous rhodium-phosphine (Rh-P) coordination polymer network, in which a CMF can reversibly dissociate the Rh-P microphases. In this way, the ligand exchange of Rh-P coordination bonds in the polymer network is accelerated, resulting in a topological rearrangement of molecular switches. This rearrangement of molecular switches enables the polymer network to release internal tension under ultrasound exposure, resulting in a CMF-induced shape-memory capability. The interconnected macroporous structure with thin pore walls is essential for allowing the CMF to effectively permeate throughout the polymer network. Potential applications of this CMF-induced shape-memory polymer can be mechanosensors or ultrasound controlled switches. Y1 - 2016 U6 - https://doi.org/10.1002/marc.201600439 SN - 1022-1336 SN - 1521-3927 VL - 37 SP - 1897 EP - 1903 PB - Wiley-VCH CY - Weinheim ER - TY - GEN A1 - Gühr, Markus T1 - Ultrafast Soft X-ray Probing of Gas Phase Molecular Dynamics N2 - The molecular ability to selectively and efficiently convert sunlight into other forms of energy like heat, bond change, or charge separation is truly remarkable. The decisive steps in these transformations often happen on a femtosecond timescale and require transitions among different electronic states that violate the Born-Oppenheimer approximation (BOA). Non-BOA transitions pose challenges to both theory and experiment. From a theoretical point of view, excited state dynamics and nonadiabatic transitions both are difficult problems (see Figure 1(a)). However, the theory on non-BOA dynamics has advanced significantly over the last two decades. Full dynamical simulations for molecules of the size of nucleobases have been possible for a couple of years and allow predictions of experimental observables like photoelectron energy or ion yield. The availability of these calculations for isolated molecules has spurred new experimental efforts to develop methods that are sufficiently different from all optical techniques. For determination of transient molecular structure, femtosecond X-ray diffraction and electron diffraction have been implemented on optically excited molecules. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 268 Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-97215 ER - TY - THES A1 - Schröder, Henning T1 - Ultrafast electron dynamics in Fe(CO)5 and Cr(CO)6 T1 - Ultraschnelle Elektronendynamik in Fe(CO)5 und Cr(CO)6 N2 - In this thesis, the two prototype catalysts Fe(CO)₅ and Cr(CO)₆ are investigated with time-resolved photoelectron spectroscopy at a high harmonic setup. In both of these metal carbonyls, a UV photon can induce the dissociation of one or more ligands of the complex. The mechanism of the dissociation has been debated over the last decades. The electronic dynamics of the first dissociation occur on the femtosecond timescale. For the experiment, an existing high harmonic setup was moved to a new location, was extended, and characterized. The modified setup can induce dynamics in gas phase samples with photon energies of 1.55eV, 3.10eV, and 4.65eV. The valence electronic structure of the samples can be probed with photon energies between 20eV and 40eV. The temporal resolution is 111fs to 262fs, depending on the combination of the two photon energies. The electronically excited intermediates of the two complexes, as well as of the reaction product Fe(CO)₄, could be observed with photoelectron spectroscopy in the gas phase for the first time. However, photoelectron spectroscopy gives access only to the final ionic states. Corresponding calculations to simulate these spectra are still in development. The peak energies and their evolution in time with respect to the initiation pump pulse have been determined, these peaks have been assigned based on literature data. The spectra of the two complexes show clear differences. The dynamics have been interpreted with the assumption that the motion of peaks in the spectra relates to the movement of the wave packet in the multidimensional energy landscape. The results largely confirm existing models for the reaction pathways. In both metal carbonyls, this pathway involves a direct excitation of the wave packet to a metal-to-ligand charge transfer state and the subsequent crossing to a dissociative ligand field state. The coupling of the electronic dynamics to the nuclear dynamics could explain the slower dissociation in Fe(CO)₅ as compared to Cr(CO)₆. N2 - Diese Dissertation handelt von der Untersuchung der zwei Modell-Katalysatoren Fe(CO)₅ und Cr(CO)₆ mittels zeitaufgelöster Photoelektronen Spektroskopie an einem High Harmonic Setup. In beiden Metallcarbonyl kann die Dissoziation von einem, oder mehreren Liganden durch ein UV Photon ausgelöst werden. Der Dissoziation-Mechanismus wurde in den letzten Jahrzehnten diskutiert. Die Abspaltung des ersten Liganden und die damit verbundenen elektronischen Dynamiken finden auf Zeitskalen von Femtosekunden statt. Für die Durchführung dieses Experiments wurde ein bestehender High Harmonic Setup in ein neues Labor verlegt. Der Aufbau wurde erweitert und charakterisiert. Mit dem modifizierten Aufbau können nun Reaktionen in Gas-Phasen-Proben mit Photonenenergien von 1.55eV, 3.10eV und 4.65eV ausgelöst werden. Dabei kann die Valenz-Elektronen-Struktur mit Photonenenergien zwischen 20eV und 40eV untersucht werden. Die Zeitauflösung liegt im Bereich von 111fs bis 262fs und hängt von der Kombination der zwei Photonenenergien ab. Die beiden Komplexe sowie Fe(CO)₄ konnten in der Gas-Phase zum ersten Mal in elektronisch angeregten Zuständen mittels zeitaufgelöster Photoelektronenspektroskopie beobachtet werden. Im Allgemeinen kann jedoch mit der Photoelektronenspektroskopie nur der ionische Endzustand untersucht werden. Modellrechnungen zu den Spektren und die Entwicklung der dazugehörigen Theorie befinden derzeit noch in der Entwicklungsphase. Die Peaks in den Spektren konnten anhand von Literatur zugeordnet werden. Die Spektren der beiden Komplexe unterscheiden sich deutlich. Zu deren Interpretation wurde die Näherung verwendet, dass die Dynamik der Peaks in den Spektren die Bewegung des Wellenpakets in der multidimensionalen Energielandschaft darstellt. Die neuen Daten bestätigen weitestgehend bestehende Modelle für die Reaktionsmechanismen. Der Reaktionsmechanismus verläuft für beide Metallcarbonyle über eine direkte Anregung des Wellenpakets in einen metal-to-ligand charge transfer Zustand. Von dem angeregten Zustand aus kann das Wellenpaket in den dissoziativen ligand field Zustand wechseln. Dass die Reaktion in Fe(CO)₅ langsamer als in Cr(CO)₆ abläuft, kann durch die Kopplung der Dynamiken von Elektronen und Kernen erklärt werden. KW - dissertation KW - Dissertation KW - photo electron spectroscopy KW - physical chemistry KW - molecular dynamics KW - high harmonic generation KW - iron pentacarbonyl KW - chromium hexacarbonyl KW - metal carbonyls KW - ultrafast KW - dynamics KW - Photoelektronen KW - Spektroskopie KW - Moleküldynamik KW - high harmonic KW - Eisenpentacarbonyl KW - Chromhexacarbonyl KW - Photodissoziation KW - photodissociation KW - ligand KW - bond Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-94589 ER - TY - THES A1 - Schmidt, Andreas T1 - Udmurt as an OV language T1 - Das Udmurtische als OV-Sprache BT - and Finnish as a VO language BT - und das Finnische als VO-Sprache N2 - This is the first study to investigate Hubert Haider's (2000, 2010, 2013, 2014) proposed systematic differences between OV and VO language in a family other than Germanic. Its aim is to gather evidence on whether basic word order is predictive of further properties of a language. The languages under investigation are the Finno-Ugric languages Udmurt (as an OV language) and Finnish (as a VO language). Counter to Kayne (1994), Haider proposes that the structure of a sentence with a head-final VP is fundamentally different from that of a sentence with a head-initial VP, e.g., OV languages do not exhibit a VP-shell structure, and they do not employ a TP layer with a structural subject position. Haider's proposed structural differences are said to result in the following empirically testable differences: (a) VP: the availability of VP-internal adverbial intervention and scrambling only in OV-VPs; (b) subjects: the lack of certain subject-object asymmetries in OV languages, i.e., lack of the subject condition and lack of superiority effects; (c) V-complexes: the availability of partial predicate fronting only in OV languages; different orderings between selecting and selected verbs; the intervention of non-verbal material between verbs only in VO languages; (d) V-particles: differences in the distribution of resultative phrases and verb particles. Udmurt and Finnish behave in line with Haider's predictions with regard to the status of the subject, with regard to the order of selecting and selected verbs, and with regard to the availability of partial predicate fronting. Moreover, Udmurt allows for adverbial intervention and scrambling, as predicted, whereas the status of these properties in Finnish could not be reliably determined due to obligatory V-to-T. There is also counterevidence to Haider's predictions: Udmurt allows for non-verbal material between verbs, and the distribution of resultative phrases and verb particles is essentially as free as the distribution of adverbial phrases in both Finno-Ugric languages. As such, Haider's theory is not falsified by the data from Udmurt and Finnish (except for his theory on verb particles), but it is also not fully supported by the data. N2 - Dies ist die erste Studie in der untersucht wird, ob sich die von Hubert Haider (2010, 2013, 2014) festgestellten, syntaktischen Unterschiede zwischen der Objekt-Verb(OV)-Sprache Deutsch und der Verb-Objekt(VO)-Sprache Englisch für eine weitere OV- und eine weitere VO-Sprache einer anderen Sprachfamilie nachweisen lassen. Damit kann gezeigt werden, ob die Grundwortstellung eine syntaktisch relevante Eigenschaft einer Sprache ist. Die zur Untersuchung ausgewählten Sprachen stammen aus der Uralischen/Finno-Ugrischen Sprachfamilie und sind die OV-Sprache Udmurtisch, gesprochen in Udmurtien (Russland), und die VO-Sprache Finnisch. Auf Grundlage der Unterschiede zwischen dem Deutschen und Englischen wurden Vorhersagen für die syntaktischen Eigenschaften des Udmurtischen und Finnischen getroffen. Diese Vorhersagen wurden mithilfe der vorhandenen Literatur zu diesen beiden Sprachen und mithilfe von neu erhobenen Daten überprüft. Für das bisher weniger erforschte Udmurtische überwiegt der Anteil an neu erhobenen Daten während für das Finnische überwieged auf die Literatur zurückgegriffen wird. Das Udmurtische stimmt bezüglich Haiders Vorhersagen überwieged mit dem Deutschen überein: (a) variable Wortstellung innerhalb der VP ist möglich (scrambling); (b) die VP-interne Trennung von Verb und direktem Objekt ist möglich (adverbial intervention); (c) die Extraktion aus präverbalen Konstituenten und insbesondere Subjekten ist möglich (subject condition); (d) in Fragen mit mehreren Interrogativelementen kann dem Interrogativsubjekt ein anderes Interrogativelement vorangehen (superiority effect); (e) Subkonstituenten der VP können vorangestellt werden (partial VP-fronting); (f) selegierte Verben gehen selektierenden Verben in kanonischer Wortstellung voraus; (g) die Abfolge der Verben in einer Serie selegierender und selektierter Verben ist variabel. Die Beobachtung zu superiority effects ist allerdings nicht aussagekräftig, weil Interrogativphrasen im Udmurtischen nicht obligatorisch vorangestellt werden müssen. Außerdem widerspricht das Udmurtische Haiders Vorhersage darin, dass (h) in sehr viel mehr Kontexten als im Deutschen nicht-verbale Elemente zwischen den Verben einer Serie von Verben auftreten können (verb clustering). Dies ist auch die einzige Gemeinsamkeit, die das Udmurtische in jenen Punkten mit dem Englischen aufweist. Wie vorhergesagt verhält sich das Finnische in den obengenannten Eigenschaften meist gegenteilig zum Udmurtischen und entsprechend zum Englischen: (c) die Extraktion aus präverbalen Konstituenten ist nicht möglich; (d) in Fragen mit mehreren Interrogativelementen kann dem Interrogativsubjekt nicht ein anderes Interrogativelement vorangehen; (e) Subkonstituenten der VP können nicht vorangestellt werden, Ausnahmefälle sind als Fälle der Voranstellung einer 'entleerten' VP zu betrachten (remnant movement); (f) selegierte Verben folgen selektierenden Verben in kanonischer Wortstellung; (g) die Abfolge der Verben in einer Serie selegierender und selektierter Verben ist nicht variabel, Ausnahmefälle sind ebenfalls als remnant movement zu betrachten. Zu Eigenschaften (a) und (b) konnte kein klares Urteil gefällt werden da das Finnische obligatorische Verbanhebung in eine Position oberhalb von VP aufweist. Das Udmurtische und das Finnische unterscheiden sich gemeinsam von den germanischen Sprachen dadurch, dass (i) Resultativphrasen und Verbpartikeln (sekundäre Prädikate) nicht ein von anderen Phrasen (z.B. Adverbialphrasen) unterscheidbarer syntaktischer Status zukommt. Diesbezüglich wird behauptet, dass Haiders Vorhersage auf der falschen Prämisse beruht, dass die syntaktischen Eigenschaften sekundärer Prädikation crosslinguistisch uniform sind. Somit kann dieser Widerspruch zu Haiders Vorhersagen nicht auf die Grundwortstellung zurückgeführt werden. Insgesamt kann anhand der Daten der Schluss gezogen werden, dass sich Haiders Vorhersagen bestätigt haben. Die OV-Sprache Udmurtisch verhält sich in Bezug auf Haiders Kriterien fast gleich der OV-Sprache Deutsch und stimmt in nur einem Punkt mit dem Englischen überein. Die VO-Sprache Finnisch hingegen ist der VO-Sprache Englisch viel ähnlicher als dem Deutschen. Schließlich: obwohl Udmurtisch und Finnisch miteinander verwandt sind und viele Gemeinsamkeiten in augenscheinlicheren Eigenschaften wie dem Lexikon oder der Morphologie aufweisen unterscheiden sie sich bezüglich Haiders syntaktischen Eigenschaften in fast allen Punkten. Die Grundwortstellung hat also einen größeren Einfluss auf die Ausprägung von Haiders Kriterien als die Verwandtschaft der Sprachen. Die Ergebnisse dieser Studie zeigen erste Evidenz dafür, dass sich die Unterschiede zwischen dem Deutschen und dem Englischen auch in anderen Sprachpaaren zeigen können. Dies ist ein erster Schritt dahin die Grundwortstellung als Prädiktor für syntaktische Eigenschaften zu etablieren. Das ist ein Anreiz, weitere Sprachen auf Haiders Kriterien hin zu untersuchen. Es ist außerdem ein Anreiz, die Grundwortstellung in der syntaktischen Theoriebildung zu berücksichtigen. Das bedeutet auch, dass Englisch nur bedingt als Vorbild für die syntaktische Analyse einiger Aspekte von OV-Sprachen angemessen ist. KW - word order KW - typology KW - syntax KW - Finno-Ugric languages KW - superiority KW - scrambling KW - subject condition KW - Wortstellung KW - Typologie KW - Syntax KW - Finno-Ugrische Sprachen Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-89465 ER - TY - JOUR A1 - Wehrhan, Marc A1 - Rauneker, Philipp A1 - Sommer, Michael T1 - UAV-Based Estimation of Carbon Exports from Heterogeneous Soil Landscapes-A Case Study from the CarboZALF Experimental Area JF - SENSORS N2 - The advantages of remote sensing using Unmanned Aerial Vehicles (UAVs) are a high spatial resolution of images, temporal flexibility and narrow-band spectral data from different wavelengths domains. This enables the detection of spatio-temporal dynamics of environmental variables, like plant-related carbon dynamics in agricultural landscapes. In this paper, we quantify spatial patterns of fresh phytomass and related carbon (C) export using imagery captured by a 12-band multispectral camera mounted on the fixed wing UAV Carolo P360. The study was performed in 2014 at the experimental area CarboZALF-D in NE Germany. From radiometrically corrected and calibrated images of lucerne (Medicago sativa), the performance of four commonly used vegetation indices (VIs) was tested using band combinations of six near-infrared bands. The highest correlation between ground-based measurements of fresh phytomass of lucerne and VIs was obtained for the Enhanced Vegetation Index (EVI) using near-infrared band b(899). The resulting map was transformed into dry phytomass and finally upscaled to total C export by harvest. The observed spatial variability at field- and plot-scale could be attributed to small-scale soil heterogeneity in part. KW - VI KW - soil landscape KW - carbon export KW - agriculture KW - multispectral KW - UAV Y1 - 2016 U6 - https://doi.org/10.3390/s16020255 SN - 1424-8220 VL - 16 PB - MDPI CY - Basel ER - TY - GEN A1 - Wehrhan, Marc A1 - Rauneker, Philipp A1 - Sommer, Michael T1 - UAV-Based estimation of carbon exports from heterogeneous soil landscapes BT - a case study from the CarboZALF experimental area T2 - Sensors N2 - The advantages of remote sensing using Unmanned Aerial Vehicles (UAVs) are a high spatial resolution of images, temporal flexibility and narrow-band spectral data from different wavelengths domains. This enables the detection of spatio-temporal dynamics of environmental variables, like plant-related carbon dynamics in agricultural landscapes. In this paper, we quantify spatial patterns of fresh phytomass and related carbon (C) export using imagery captured by a 12-band multispectral camera mounted on the fixed wing UAV Carolo P360. The study was performed in 2014 at the experimental area CarboZALF-D in NE Germany. From radiometrically corrected and calibrated images of lucerne (Medicago sativa), the performance of four commonly used vegetation indices (VIs) was tested using band combinations of six near-infrared bands. The highest correlation between ground-based measurements of fresh phytomass of lucerne and VIs was obtained for the Enhanced Vegetation Index (EVI) using near-infrared band b(899). The resulting map was transformed into dry phytomass and finally upscaled to total C export by harvest. The observed spatial variability at field- and plot-scale could be attributed to small-scale soil heterogeneity in part. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 451 KW - VI KW - soil landscape KW - carbon export KW - agriculture KW - multispectral KW - UAV Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-407706 ER - TY - THES A1 - Hildebrand, Viet T1 - Twofold switchable block copolymers based on new polyzwitterions T1 - Neue Polyzwitterionbasierte Blockcopolymere mit „Schizophrenem Verhalten“ N2 - In complement to the well-established zwitterionic monomers 3-((2-(methacryloyloxy)ethyl)dimethylammonio)propane-1-sulfonate (“SPE”) and 3-((3-methacrylamidopropyl)dimethylammonio)propane-1-sulfonate (“SPP”), the closely related sulfobetaine monomers were synthesized and polymerized by reversible addition-fragmentation chain transfer (RAFT) polymerization, using a fluorophore labeled RAFT agent. The polyzwitterions of systematically varied molar mass were characterized with respect to their solubility in water, deuterated water, and aqueous salt solutions. These poly(sulfobetaine)s show thermoresponsive behavior in water, exhibiting upper critical solution temperatures (UCST). Phase transition temperatures depend notably on the molar mass and polymer concentration, and are much higher in D2O than in H2O. Also, the phase transition temperatures are effectively modulated by the addition of salts. The individual effects can be in parts correlated to the Hofmeister series for the anions studied. Still, they depend in a complex way on the concentration and the nature of the added electrolytes, on the one hand, and on the detailed structure of the zwitterionic side chain, on the other hand. For the polymers with the same zwitterionic side chain, it is found that methacrylamide-based poly(sulfobetaine)s exhibit higher UCST-type transition temperatures than their methacrylate analogs. The extension of the distance between polymerizable unit and zwitterionic groups from 2 to 3 methylene units decreases the UCST-type transition temperatures. Poly(sulfobetaine)s derived from aliphatic esters show higher UCST-type transition temperatures than their analogs featuring cyclic ammonium cations. The UCST-type transition temperatures increase markedly with spacer length separating the cationic and anionic moieties from 3 to 4 methylene units. Thus, apparently small variations of their chemical structure strongly affect the phase behavior of the polyzwitterions in specific aqueous environments. Water-soluble block copolymers were prepared from the zwitterionic monomers and the non-ionic monomer N-isopropylmethacrylamide (“NIPMAM”) by the RAFT polymerization. Such block copolymers with two hydrophilic blocks exhibit twofold thermoresponsive behavior in water. The poly(sulfobetaine) block shows an UCST, whereas the poly(NIPMAM) block exhibits a lower critical solution temperature (LCST). This constellation induces a structure inversion of the solvophobic aggregate, called “schizophrenic micelle”. Depending on the relative positions of the two different phase transitions, the block copolymer passes through a molecularly dissolved or an insoluble intermediate regime, which can be modulated by the polymer concentration or by the addition of salt. Whereas, at low temperature, the poly(sulfobetaine) block forms polar aggregates that are kept in solution by the poly(NIPMAM) block, at high temperature, the poly(NIPMAM) block forms hydrophobic aggregates that are kept in solution by the poly(sulfobetaine) block. Thus, aggregates can be prepared in water, which switch reversibly their “inside” to the “outside”, and vice versa. N2 - Diese Arbeit befasst sich mit der Synthese und Charakterisierung von doppelt thermisch-responsiven Blockcopolymeren mit einem polaren nicht-ionischen Block (der einen LCST-Übergang in wässriger Lösung induziert) und einem zwitterionischen Block (der einen UCST-Übergang aufweisen soll), der durch Salzzusatz über einen weiten Temperaturbereich modulierbar ist. Dafür wurden geeignete zwitterionische Polymer¬blöcke identifiziert und hergestellt, die ein derartiges Löslichkeitsprofil aufweisen. Da bislang nur relativ wenige Poly-sulfobetaine beschrieben sind und entsprechend das wässrige Phasenverhalten nur für einzelne ausgewählte Polymere bekannt ist, wurde ein Grundverständnis von chemischer Struktur und Phasen¬übergangs¬verhalten durch eine systematische Variation des Substitutionsmusters angestrebt. Die als geeignet erkannten Sulfobetain-Monomere wurden mit dem nicht-ionischen Monomer N-Isopropyl-methacrylamid („NIPMAM“) zu Blockcopolymeren von unterschiedlicher Größe und Blocklängen zusammengefügt. Die neuen Blockcopolymere wurden anschließend bezüglich der Lage der Phasenübergänge mit Trübheitsmessungen untersucht. Es wurden 2 Serien neuer zwitterionischer Monomere synthetisiert, deren Struktur den sehr gut untersuchten 3-((2-(methacryloyloxy)ethyl)dimethylammonio)propane-1-sulfonate („SPE“) und 3-((3-methacrylamidopropyl)dimethylammonio)propane-1-sulfonate („SPP“) ähnlich ist. Aus den Monomeren wurden fluoreszenz-markierte Homopolymere mit unterschiedlichen Molmassen mittels der Reversiblen Additions-Fragmentierungs Kettenübertragungs (RAFT) – Polymerisation unter Verwendung eines geeigneten RAFT Reagenzes synthetisiert. Die Poly¬sulfobetaine wurden bezüglich ihrer Löslichkeit in Wasser, in deuteriertem Wasser und in Salzlösungen untersucht. Ihr wässriges Phasenverhalten mit einem UCST-Übergang ist stark abhängig von ihrer Molmasse und von der Polymerkonzentration der untersuchten Lösung. Auffällig ist, dass die Phasenübergangstemperatur in D2O deutlich höher liegt als in H2O. Des Weiteren konnten die Löslichkeit und Phasen-übergangstemperatur durch Salzzusatz effektiv moduliert werden. Prinzipiell stellte sich bei den untersuchten Anionen heraus, dass das Einsalzen bzw. das Aussalzen der empirischen Hofmeister Serie folgt. Dabei hängen die individuellen Effekte sehr stark von der Konzentration und von der Art des Salzes, aber auch in nicht-trivialer Weise von der detaillierten zwitterionischen Struktur stark ab. Durch die systematische Variation der Monomerstruktur wurden interessante Tendenzen offenbar. Die Methacrylamid-basierte Polysulfobetaine besitzen eine höhere Phasenübergangstemperatur als ihre Methacrylat-basierten Analoga. Die Vergrößerung der Distanz zwischen Polymerrückrat und der zwitterionischen Gruppe von 2 auf 3 Methylengruppen führt zu einer Erniedrigung der Phasenübergangstemperatur. Polysulfobetaine mit aliphatischen Resten (Methyl-gruppen) am Ammonium-Ion haben eine höhere Phasenübergangstemperatur als ihre Analoga, in denen der Ammonium-Stickstoff Teil eines Heterozyklus ist. Als letzte Strukturvariable wurde die Distanz zwischen Kation und Anion von 3 auf 4 Methylengruppen vergrößert; diese Änderung führt zu einer massiven Erhöhung der Phasenübergangstemperatur. Die Polysulfobetaine wurden verwendet, um mit dem nicht-ionischen Monomer NIPMAM wasserlösliche Blockcopolymere mittels der RAFT Polymerisation herzustellen. Diese Blockcopolymere besitzen doppelt thermisch-responsives Verhalten (mit einem UCST- und einem LCST-Übergang). Die Besonderheit einer solchen Konstellation ist, dass eine Strukturinversion der solvophoben Aggregate induziert werden kann. Daher werden solche Blockcopolymer-Assoziate auch als „schizophrene Mizellen“ bezeichnet. Je nach der relativen Lage der beiden Phasenübergänge, die sich durch Polymerkonzentration oder durch Salzzusatz einstellen lässt, läuft die Strukturinversion über ein molekular gelöstes oder über ein unlösliches Zwischenstadium ab. Der Polysulfobetain-Block bildet bei niedriger Temperatur Aggregate, die durch den gelösten poly(NIPMAM)-Block in Lösung gehalten werden. Dahingegen bildet der poly(NIPMAM)-Block bei hoher Temperatur Aggregate, welche ihrerseits durch den gelösten Polysulfobetain-Block in Lösung gehalten werden. Somit werden „schizophrene“ Aggregate in Wasser erzeugt, die fähig sind, reversibel ihr „Inneres“ nach „Außen“ und umgekehrt zu schalten durch Nutzen eines einfachen thermischen Impulses. KW - switchable block copolymer KW - polyzwitterion KW - polysulfobetaine KW - thermoresponsive polymers KW - schizophrenic behavior KW - LCST and UCST KW - electrolyte sensitivity KW - zweifach schaltbare Blockcopolymere KW - Polyzwitterion KW - Polysulfobetaine KW - thermoresponsive Polymere KW - schizophrenes Verhalten KW - LCST und UCST KW - Elektrolytempfindlichkeit Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-101372 ER - TY - JOUR A1 - Wessig, Pablo A1 - Behrends, Nicole A1 - Kumke, Michael Uwe A1 - Eisold, Ursula A1 - Meiling, Til A1 - Hille, Carsten T1 - Two-photon FRET pairs based on coumarin and DBD dyes JF - RSC Advances N2 - The synthesis and photophysical properties of two new FRET pairs based on coumarin as a donor and DBD dye as an acceptor are described. The introduction of a bromo atom dramatically increases the two-photon excitation (2PE) cross section providing a 2PE-FRET system, which is also suitable for 2PE-FLIM. Y1 - 2016 U6 - https://doi.org/10.1039/c6ra03983a SN - 2046-2069 VL - 6 SP - 33510 EP - 33513 PB - Royal Society of Chemistry CY - Cambridge ER - TY - GEN A1 - Wessig, Pablo A1 - Hille, Carsten A1 - Kumke, Michael Uwe A1 - Meiling, Till Thomas A1 - Behrends, Nicole A1 - Eisold, Ursula T1 - Two-photon FRET pairs based on coumarin and DBD dyes N2 - The synthesis and photophysical properties of two new FRET pairs based on coumarin as a donor and DBD dye as an acceptor are described. The introduction of a bromo atom dramatically increases the two-photon excitation (2PE) cross section providing a 2PE-FRET system, which is also suitable for 2PE-FLIM. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 318 KW - resonance energy-tansfer KW - conformational-changes KW - microscopy KW - proteins KW - acid Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-394445 SP - 33510 EP - 33513 ER - TY - JOUR A1 - Patel, Riddhi P. A1 - Förster, Daniel W. A1 - Kitchener, Andrew C. A1 - Rayan, Mark D. A1 - Mohamed, Shariff W. A1 - Werner, Laura A1 - Lenz, Dorina A1 - Pfestorf, Hans A1 - Kramer-Schadt, Stephanie A1 - Radchuk, Viktoriia A1 - Fickel, Jörns A1 - Wilting, Andreas T1 - Two species of Southeast Asian cats in the genus Catopuma with diverging histories: an island endemic forest specialist and a widespread habitat generalist JF - Royal Society Open Science N2 - Background. The bay cat Catopuma badia is endemic to Borneo, whereas its sister species the Asian golden cat Catopuma temminckii is distributed from the Himalayas and southern China through Indochina, Peninsular Malaysia and Sumatra. Based onmorphological data, up to five subspecies of the Asian golden cat have been recognized, but a taxonomic assessment, including molecular data and morphological characters, is still lacking. Results. We combined molecular data (whole mitochondrial genomes), morphological data (pelage) and species distribution projections (up to the Late Pleistocene) to infer how environmental changes may have influenced the distribution of these sister species over the past 120 000 years. The molecular analysis was based on sequenced mitogenomes of 3 bay cats and 40 Asian golden cats derived mainly from archival samples. Our molecular data suggested a time of split between the two species approximately 3.16 Ma and revealed very low nucleotide diversity within the Asian golden cat population, which supports recent expansion of the population. Discussion. The low nucleotide diversity suggested a population bottleneck in the Asian golden cat, possibly caused by the eruption of the Toba volcano in Northern Sumatra (approx. 74 kya), followed by a continuous population expansion in the Late Pleistocene/Early Holocene. Species distribution projections, the reconstruction of the demographic history, a genetic isolation-by-distance pattern and a gradual variation of pelage pattern support the hypothesis of a post-Toba population expansion of the Asian golden cat from south China/Indochina to PeninsularMalaysia and Sumatra. Our findings reject the current classification of five subspecies for the Asian golden cat, but instead support either a monotypic species or one comprising two subspecies: (i) the Sunda golden cat, distributed south of the Isthmus of Kra: C. t. temminckii and (ii) Indochinese, Indian, Himalayan and Chinese golden cats, occurring north of the Isthmus: C. t. moormensis. KW - Felidae KW - Southeast Asia KW - last glacial maximum KW - Toba volcanic eruption KW - hybrid capture KW - next generation sequencing Y1 - 2016 U6 - https://doi.org/10.1098/rsos.160350 SN - 2054-5703 VL - 3 SP - 741 EP - 752 PB - Royal Society CY - London ER - TY - GEN A1 - Barniske, Andreas A1 - Oskinova, Lidia M. A1 - Hamann, Wolf-Rainer T1 - Two extremely luminous WN stars in the Galactic center with circumstellar emission from dust and gas (vol 486, pg 971, 2008) T2 - Physical chemistry, chemical physics : a journal of European Chemical Societies KW - stars: Wolf-Rayet KW - HII regions KW - Galaxy: center KW - stars: individual: WR 102ka KW - stars: individual: WR 102c KW - errata, addenda Y1 - 2016 U6 - https://doi.org/10.1051/0004-6361/200809568e SN - 1432-0746 VL - 587 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Wentrup, Curt A1 - Koch, Rainer A1 - Kleinpeter, Erich T1 - Twisted C=C Double Bonds with Very Low Rotational Barriers in Dioxanediones and Isoxazolones Determined by Low-Temperature Dynamic NMR Spectroscopy and Computational Chemistry JF - European journal of organic chemistry KW - NMR spectroscopy KW - Twisted double bonds KW - Push-pull effect KW - Density functional calculations Y1 - 2016 U6 - https://doi.org/10.1002/ejoc.201600931 SN - 1434-193X SN - 1099-0690 SP - 4985 EP - 4990 PB - Wiley-VCH CY - Weinheim ER - TY - THES A1 - Hohenbrink, Tobias Ludwig T1 - Turning a problem into a solution: heterogeneities in soil hydrology T1 - Ein Problem zur Lösung machen: Heterogenitäten in der Bodenhydrologie N2 - It is commonly recognized that soil moisture exhibits spatial heterogeneities occurring in a wide range of scales. These heterogeneities are caused by different factors ranging from soil structure at the plot scale to land use at the landscape scale. There is an urgent need for effi-cient approaches to deal with soil moisture heterogeneity at large scales, where manage-ment decisions are usually made. The aim of this dissertation was to test innovative ap-proaches for making efficient use of standard soil hydrological data in order to assess seep-age rates and main controls on observed hydrological behavior, including the role of soil het-erogeneities. As a first step, the applicability of a simplified Buckingham-Darcy method to estimate deep seepage fluxes from point information of soil moisture dynamics was assessed. This was done in a numerical experiment considering a broad range of soil textures and textural het-erogeneities. The method performed well for most soil texture classes. However, in pure sand where seepage fluxes were dominated by heterogeneous flow fields it turned out to be not applicable, because it simply neglects the effect of water flow heterogeneity. In this study a need for new efficient approaches to handle heterogeneities in one-dimensional water flux models was identified. As a further step, an approach to turn the problem of soil moisture heterogeneity into a solu-tion was presented: Principal component analysis was applied to make use of the variability among soil moisture time series for analyzing apparently complex soil hydrological systems. It can be used for identifying the main controls on the hydrological behavior, quantifying their relevance, and describing their particular effects by functional averaged time series. The ap-proach was firstly tested with soil moisture time series simulated for different texture classes in homogeneous and heterogeneous model domains. Afterwards, it was applied to 57 mois-ture time series measured in a multifactorial long term field experiment in Northeast Germa-ny. The dimensionality of both data sets was rather low, because more than 85 % of the total moisture variance could already be explained by the hydrological input signal and by signal transformation with soil depth. The perspective of signal transformation, i.e. analyzing how hydrological input signals (e.g., rainfall, snow melt) propagate through the vadose zone, turned out to be a valuable supplement to the common mass flux considerations. Neither different textures nor spatial heterogeneities affected the general kind of signal transfor-mation showing that complex spatial structures do not necessarily evoke a complex hydro-logical behavior. In case of the field measured data another 3.6% of the total variance was unambiguously explained by different cropping systems. Additionally, it was shown that dif-ferent soil tillage practices did not affect the soil moisture dynamics at all. The presented approach does not require a priori assumptions about the nature of physical processes, and it is not restricted to specific scales. Thus, it opens various possibilities to in-corporate the key information from monitoring data sets into the modeling exercise and thereby reduce model uncertainties. N2 - Es ist allgemein anerkannt, dass Bodenfeuchte auf verschiedenen Raumskalen räumliche Heterogenitäten aufweist. Diese Heterogenitäten werden durch verschiedene Faktoren verursacht, die auf den unterschiedlichen Skalen wirken. Dies können z.B. die Bodenstruktur auf Plotskala oder die Landnutzung auf Landschaftsskala sein. Es werden dringend effiziente Ansätze benötigt, um mit den Heterogenitäten der Bodenfeuchte umzugehen. Dies gilt be-sonders für große Skalen, auf denen in der Regel weitreichende Managemententscheidun-gen getroffen werden. Das Ziel dieser Dissertation war es, effiziente Methoden zu testen, die es ermöglichen auf Basis bodenhydrologischer Daten sowohl Sickerwasserraten als auch die Haupteinflussfaktoren der Bodenfeuchtedynamik zu bestimmen. Dies bezieht Effekte von Bodenheterogenitäten mit ein. In einem ersten Schritt wurde die Eignung einer vereinfachten Buckingham-Darcy Methode zur Abschätzung von Sickerwasserflüssen auf Grundlage punktuell gemessener Zeitreihen der Bodenfeuchte untersucht. Hierzu wurde eine Simulationsstudie durchgeführt, in der ein breites Spektrum an Bodentexturen und Texturheterogenitäten berücksichtigt wurde. Die Methode lieferte gute Ergebnisse für die meisten Texturklassen. In reinem Sand jedoch stell-te sie sich als nicht anwendbar heraus, da hier Sickerwasserflüsse von heterogenen Fließfel-dern dominiert wurden. In dieser Studie wurde ein Bedarf an neuen effizienten Ansätzen für den Umgang mit Heterogenitäten in eindimensionalen Wasserflussmodellen identifiziert. In einem weiteren Schritt wurde ein Ansatz vorgestellt, um aus dem Problem der Boden-feuchteheterogenität eine Lösung zu machen: In einer Hauptkomponentenanalyse wurde die Variabilität zwischen Bodenfeuchtezeitreihen genutzt, um die wahre Komplexität bo-denhydrologischer Systeme zu analysieren. Auf diesem Weg ist es möglich die Haupteinfluss-faktoren des hydrologischen Verhaltens zu identifizieren, ihre Relevanz zu quantifizieren und ihre jeweiligen Effekte als funktional gemittelte Zeitreihen zu beschreiben. Der Ansatz wurde zunächst mit simulierten Bodenfeuchtezeitreihen für unterschiedliche Texturklassen im ho-mogenen und heterogenen Fall getestet. Anschließend wurde die Methode auf 57 Boden-feuchtezeitreihen angewendet, die in einem Langzeitfeldexperiment in Nordostdeutschland gemessen wurden. Die Dimensionalität beider Datensätze war gering, da mehr als 85 % der gesamten Boden-feuchtevarianz bereits durch das hydrologische Eingangssignal und die Transformation dieses Signals mit zunehmender Bodentiefe erklärt werden konnten. Analysen der Signaltransfor-mation haben sich als wertvolle Ergänzung zu den weit verbreiteten Massenflussbetrachtun-gen herausgestellt. Hierbei wird untersucht, wie sich hydrologische Eingangssignale (z.B. Nie-derschlag oder Schneeschmelze) in der vadosen Zone fortpflanzen. Die generellen Muster der Signaltransformation wurden weder durch verschiedene Bodentexturen noch durch räumliche Heterogeneitäten beeinfluss. Dies zeigt, dass komplexe räumliche Strukturen nicht zwangsläufig ein komplexes hydrologisches Verhalten hervorrufen. Im Fall der Felddaten wurden weitere 3,6 % der Gesamtvarianz durch verschiedene Fruchtfolgen erklärt. Darüber hinaus konnte gezeigt werden, dass die Bodenbearbeitung keinen Einfluss auf die Boden-feuchtedynamik hatte. Der vorgestellte Ansatz erfordert keine Vorannahmen über physikalische Prozesse und ist nicht auf eine bestimmte Skala begrenzt. Dadurch ergeben sich viele Möglichkeiten, wichtige Informationen aus Monitoringdatensätzen in die Modellbildung einzubeziehen und damit Modell-unsicherheiten zu verringern. KW - soil hydrology KW - soil heterogeneity KW - soil moisture KW - deep seepage KW - time series analysis KW - transformation of hydrological signals KW - Bodenhydrologie KW - Bodenheterogenität KW - Bodenfeuchte KW - Tiefenversickerung KW - Zeitreihenanalyse KW - Transformation hydrologischer Signale Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-101485 ER - TY - JOUR A1 - Koshkina, Olga A1 - Westmeier, Dana A1 - Lang, Thomas A1 - Bantz, Christoph A1 - Hahlbrock, Angelina A1 - Würth, Christian A1 - Resch-Genger, Ute A1 - Braun, Ulrike A1 - Thiermann, Raphael A1 - Weise, Christoph A1 - Eravci, Murat A1 - Mohr, Benjamin A1 - Schlaad, Helmut A1 - Stauber, Roland H. A1 - Docter, Dominic A1 - Bertin, Annabelle A1 - Maskos, Michael T1 - Tuning the Surface of Nanoparticles: Impact of Poly(2-ethyl-2-oxazoline) on Protein Adsorption in Serum and Cellular Uptake JF - Macromolecular bioscience N2 - Due to the adsorption of biomolecules, the control of the biodistribution of nanoparticles is still one of the major challenges of nanomedicine. Poly(2-ethyl-2-oxazoline) (PEtOx) for surface modification of nanoparticles is applied and both protein adsorption and cellular uptake of PEtOxylated nanoparticles versus nanoparticles coated with poly(ethylene glycol) (PEG) and non-coated positively and negatively charged nanoparticles are compared. Therefore, fluorescent poly(organosiloxane) nanoparticles of 15 nm radius are synthesized, which are used as a scaffold for surface modification in a grafting onto approach. With multi-angle dynamic light scattering, asymmetrical flow field-flow fractionation, gel electrophoresis, and liquid chromatography-mass spectrometry, it is demonstrated that protein adsorption on PEtOxylated nanoparticles is extremely low, similar as on PEGylated nanoparticles. Moreover, quantitative microscopy reveals that PEtOxylation significantly reduces the non-specific cellular uptake, particularly by macrophage-like cells. Collectively, studies demonstrate that PEtOx is a very effective alternative to PEG for stealth modification of the surface of nanoparticles. KW - cellular uptake KW - nanoparticles KW - poly(2-ethyl-2oxazoline) KW - poly(ethylene glycol) KW - protein adsorption Y1 - 2016 U6 - https://doi.org/10.1002/mabi.201600074 SN - 1616-5187 SN - 1616-5195 VL - 16 SP - 1287 EP - 1300 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Verborgh, Ruben A1 - Vander Sande, Miel A1 - Hartig, Olaf A1 - Van Herwegen, Joachim A1 - De Vocht, Laurens A1 - De Meester, Ben A1 - Haesendonck, Gerald A1 - Colpaert, Pieter T1 - Triple Pattern Fragments: A low-cost knowledge graph interface for the Web JF - Web semantics : science, services and agents on the World Wide Web N2 - Billions of Linked Data triples exist in thousands of RDF knowledge graphs on the Web, but few of those graphs can be queried live from Web applications. Only a limited number of knowledge graphs are available in a queryable interface, and existing interfaces can be expensive to host at high availability. To mitigate this shortage of live queryable Linked Data, we designed a low-cost Triple Pattern Fragments interface for servers, and a client-side algorithm that evaluates SPARQL queries against this interface. This article describes the Linked Data Fragments framework to analyze Web interfaces to Linked Data and uses this framework as a basis to define Triple Pattern Fragments. We describe client-side querying for single knowledge graphs and federations thereof. Our evaluation verifies that this technique reduces server load and increases caching effectiveness, which leads to lower costs to maintain high server availability. These benefits come at the expense of increased bandwidth and slower, but more stable query execution times. These results substantiate the claim that lightweight interfaces can lower the cost for knowledge publishers compared to more expressive endpoints, while enabling applications to query the publishers’ data with the necessary reliability. KW - Linked Data KW - Linked Data Fragments KW - Querying KW - SPARQL Y1 - 2016 U6 - https://doi.org/10.1016/j.websem.2016.03.003 SN - 1570-8268 VL - 37-38 SP - 184 EP - 206 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kruse, Stefan A1 - Wieczorek, Mareike A1 - Jeltsch, Florian A1 - Herzschuh, Ulrike T1 - Treeline dynamics in Siberia under changing climates as inferred from an individual-based model for Larix JF - Ecological modelling : international journal on ecological modelling and engineering and systems ecolog KW - Forest change KW - IBM KW - ODD model description KW - Larix gmelinii KW - Permafrost ecosystem KW - Time-lag effects Y1 - 2016 U6 - https://doi.org/10.1016/j.ecolmodel.2016.08.003 SN - 0304-3800 SN - 1872-7026 VL - 338 SP - 101 EP - 121 PB - Elsevier CY - Amsterdam ER -