TY - JOUR A1 - Trukenbrod, Hans Arne A1 - Engbert, Ralf T1 - Eye movements in a sequential scanning task - evidence for distributed processing JF - Journal of vision N2 - Current models of eye movement control are derived from theories assuming serial processing of single items or from theories based on parallel processing of multiple items at a time. This issue has persisted because most investigated paradigms generated data compatible with both serial and parallel models. Here, we study eye movements in a sequential scanning task, where stimulus n indicates the position of the next stimulus n + 1. We investigate whether eye movements are controlled by sequential attention shifts when the task requires serial order of processing. Our measures of distributed processing in the form of parafoveal-on-foveal effects, long-range modulations of target selection, and skipping saccades provide evidence against models strictly based on serial attention shifts. We conclude that our results lend support to parallel processing as a strategy for eye movement control. KW - eye movements KW - distributed processing KW - sequential attention shifts KW - parafoveal-on-foveal effects KW - skipping costs/benefits Y1 - 2012 U6 - https://doi.org/10.1167/12.1.5 SN - 1534-7362 VL - 12 IS - 1 PB - Association for Research in Vision and Opthalmology CY - Rockville ER - TY - JOUR A1 - Korup, Oliver A1 - Görüm, Tolga A1 - Hayakawa, Yuichi T1 - Without power? - Landslide inventories in the face of climate change JF - Earth surface processes and landforms : the journal of the British Geomorphological Research Group N2 - Projected scenarios of climate change involve general predictions about the likely changes to the magnitude and frequency of landslides, particularly as a consequence of altered precipitation and temperature regimes. Whether such landslide response to contemporary or past climate change may be captured in differing scaling statistics of landslide size distributions and the erosion rates derived thereof remains debated. We test this notion with simple Monte Carlo and bootstrap simulations of statistical models commonly used to characterize empirical landslide size distributions. Our results show that significant changes to total volumes contained in such inventories may be masked by statistically indistinguishable scaling parameters, critically depending on, among others, the size of the largest of landslides recorded. Conversely, comparable model parameter values may obscure significant, i.e. more than twofold, changes to landslide occurrence, and thus inferred rates of hillslope denudation and sediment delivery to drainage networks. A time series of some of Earth's largest mass movements reveals clustering near and partly before the last glacial-interglacial transition and a distinct step-over from white noise to temporal clustering around this period. However, elucidating whether this is a distinct signal of first-order climate-change impact on slope stability or simply coincides with a transition from short-term statistical noise to long-term steady-state conditions remains an important research challenge. KW - landslide KW - climate change KW - magnitude & frequency Y1 - 2012 U6 - https://doi.org/10.1002/esp.2248 SN - 0197-9337 VL - 37 IS - 1 SP - 92 EP - 99 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Huggel, Christian A1 - Clague, John J. A1 - Korup, Oliver T1 - Is climate change responsible for changing landslide activity in high mountains? JF - Earth surface processes and landforms : the journal of the British Geomorphological Research Group N2 - Climate change, manifested by an increase in mean, minimum, and maximum temperatures and by more intense rainstorms, is becoming more evident in many regions. An important consequence of these changes may be an increase in landslides in high mountains. More research, however, is necessary to detect changes in landslide magnitude and frequency related to contemporary climate, particularly in alpine regions hosting glaciers, permafrost, and snow. These regions not only are sensitive to changes in both temperature and precipitation, but are also areas in which landslides are ubiquitous even under a stable climate. We analyze a series of catastrophic slope failures that occurred in the mountains of Europe, the Americas, and the Caucasus since the end of the 1990s. We distinguish between rock and ice avalanches, debris flows from de-glaciated areas, and landslides that involve dynamic interactions with glacial and river processes. Analysis of these events indicates several important controls on slope stability in high mountains, including: the non-linear response of firn and ice to warming; three-dimensional warming of subsurface bedrock and its relation to site geology; de-glaciation accompanied by exposure of new sediment; and combined short-term effects of precipitation and temperature. Based on several case studies, we propose that the following mechanisms can significantly alter landslide magnitude and frequency, and thus hazard, under warming conditions: (1) positive feedbacks acting on mass movement processes that after an initial climatic stimulus may evolve independently of climate change; (2) threshold behavior and tipping points in geomorphic systems; (3) storage of sediment and ice involving important lag-time effects. KW - climate change KW - landslides KW - glaciers KW - permafrost Y1 - 2012 U6 - https://doi.org/10.1002/esp.2223 SN - 0197-9337 VL - 37 IS - 1 SP - 77 EP - 91 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Baranac-Stojanovic, Marija A1 - Koch, Andreas A1 - Kleinpeter, Erich T1 - Is the conventional interpretation of the anisotropic effects of C=C double bonds and aromatic rings in NMR spectra in terms of the p-electron shielding/deshielding contributions correct? JF - Chemistry - a European journal N2 - Based on the nucleus-independent chemical shift (NICS) concept, isotropic magnetic shielding values have been computed along the three Cartesian axes for ethene, cyclobutadiene, benzene, naphthalene, and benzocyclobutadiene, starting from the molecular/ring center up to 10 angstrom away. These through-space NMR spectroscopic shielding (TSNMRS) values, which reflect the anisotropic effects, have been broken down into contributions from localized- and canonical molecular orbitals (LMOs and CMOs); these contributions revealed that the proton NMR spectroscopic chemical shifts of nuclei that are spatially close to the C?C double bond or the aromatic ring should not be explained in terms of the conventionally accepted p-electron shielding/deshielding effects. In fact, these effects followed the predictions only for the antiaromatic cyclobutadiene ring. KW - ab initio calculations KW - anisotropic effects KW - NMR spectroscopy KW - nucleus-independent chemical shift KW - pi interactions Y1 - 2012 U6 - https://doi.org/10.1002/chem.201101882 SN - 0947-6539 VL - 18 IS - 1 SP - 370 EP - 376 PB - Wiley-Blackwell CY - Malden ER - TY - JOUR A1 - Elsner, Birgit A1 - Schellhas, Bernd T1 - The acquisition of flexible tool use in preschoolers the impact of prior experience JF - Zeitschrift für Psychologie = Journal of psychology N2 - To investigate how preschoolers acquire a tool use strategy and how they adapt their tool use to a changed situation, 2- to 4-year-olds were asked to retrieve chips from a transparent box with a rod, either by stabbing and lifting through a top opening or by pushing through a front and a back opening. In both conditions, about 40% of the children acquired effective tool use by individual learning, and 90% of the other children learned this by observing only one demonstration. When confronted with a changed situation (i.e., previous opening covered, alternative opening uncovered), children perseverated with the recently learned, but now ineffective tool use strategy. Neither age nor acquisition type of the first strategy affected preschoolers' perseverations. Results indicate that prior tool use experiences have differential effects in situations that require either transferring known functions to novel objects or using a familiar tool for an alternative purpose. KW - tool use KW - preschoolers (2-4 years) KW - learning KW - transfer KW - action planning Y1 - 2012 U6 - https://doi.org/10.1027/2151-2604/a000090 SN - 2190-8370 VL - 220 IS - 1 SP - 44 EP - 49 PB - Hogrefe CY - Göttingen ER - TY - JOUR A1 - Silva-Iturriza, Adriana A1 - Ketmaier, Valerio A1 - Tiedemann, Ralph T1 - Profound population structure in the Philippine Bulbul Hypsipetes philippinus (Pycnonotidae, Ayes) is not reflected in its Haemoproteus haemosporidian parasite JF - Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics and infectious diseases (MEEGID) N2 - In this study we used molecular markers to screen for the occurrence and prevalence of the three most common haemosporidian genera (Haemoproteus, Plasmodium, and Leucocytozoon) in blood samples of the Philippine Bulbul (Hypsipetes philippinus), a thrush-size passerine bird endemic to the Philippine Archipelago. We then used molecular data to ask whether the phylogeographic patterns in this insular host-parasite system might follow similar evolutionary trajectories or not. We took advantage of a previous study describing the pattern of genetic structuring in the Philippine Bulbul across the Central Philippine Archipelago (6 islands, 7 populations and 58 individuals; three mitochondrial DNA genes). The very same birds were here screened for the occurrence of parasites by species-specific PCR assays of the mitochondrial cytochrome b gene (471 base pairs). Twenty-eight out of the 58 analysed birds had Haemoproteus (48%) infections while just 2% of the birds were infected with either Leucocytozoon or Plasmodium. Sixteen of the 28 birds carrying Haemoproteus had multiple infections. The phylogeography of the Philippine Bulbul mostly reflects the geographical origin of samples and it is consistent with the occurrence of two different subspecies on (1) Semirara and (2) Carabao, Boracay, North Gigante, Panay, and Negros, respectively. Haemoproteus phylogeography shows very little geographical structure, suggesting extensive gene flow among locations. While movements of birds among islands seem very sporadic, we found co-occurring evolutionary divergent parasite lineages. We conclude that historical processes have played a major role in shaping the host phylogeography, while they have left no signature in that of the parasites. Here ongoing population processes, possibly multiple reinvasions mediated by other hosts, are predominant. KW - Haemoproteus KW - Hypsipetes philippinus KW - Comparative phylogeography KW - mtDNA Y1 - 2012 U6 - https://doi.org/10.1016/j.meegid.2011.10.024 SN - 1567-1348 VL - 12 IS - 1 SP - 127 EP - 136 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Scheffler, Christiane A1 - Obermüller, Janina T1 - Development of fat distribution patterns in children and its association with the type of body shape assessed by the Metric-Index JF - Journal of biological and clinical anthropology : Anthropologischer Anzeiger ; Mitteilungsorgan der Gesellschaft für Anthropologie N2 - The present cross-sectional anthropometric study evaluates new approaches in preventing overweight in children. Anthropometric data were obtained in 289 German children (146 boys, 143 girls) aged 6-11 years and 41 20-29 year old German female students for describing the type of body shape by Metric-Index (thoracic breadth, thoracic depth, height). The data were correlated with 15 fat layers measured with a lipometer with Principal Component Analyses and ANOVA. In females the android respectively gynoid type of body shape was significantly associated with the pyknomorphic respectively leptomorphic type. The study demonstrates that this pattern is established by an age of 8 years, when the earliest maturing children start to enter puberty. This pattern can be used to check the individual's risk of overweight and to recommend preventive healthcare interventions. KW - school children KW - type of body shape KW - risk of overweight KW - prevention Y1 - 2012 U6 - https://doi.org/10.1127/0003-5548/2011/0138 SN - 0003-5548 VL - 69 IS - 1 SP - 45 EP - 55 PB - Schweizerbart CY - Stuttgart ER - TY - JOUR A1 - Pollatos, Olga A1 - Herbert, Beate M. A1 - Fuestoes, Juergen A1 - Weimer, Katja A1 - Enck, Paul A1 - Zipfel, Stephan T1 - Food deprivation sensitizes pain perception JF - International journal of psychophysiology : official journal of the International Organization of Psychophysiology N2 - While food deprivation has known effects on sympathovagal balance, little is known about hunger's influence on the perception of pain. Since autonomic activities influence many cognitive and emotional processes, this suggests that food deprivation should interact with the perception of pain. This study analyzed the possible effects of short-term food deprivation on pain sensitivity in healthy female participants. This study was comprised of 32 healthy female participants who underwent a 48-hr inpatient hospital investigation. Prior to testing, heart rate and heart rate variability were assessed. After a standardized breakfast, day 1 measurements were taken. Food intake was then not allowed again until the following evening for 22 participants (experimental group), while 12 participants were served standard meals (control group). Pain threshold and tolerance were assessed at 10:00 a. m. on both days using a pressure algometer. Additionally pain experience was examined. Food deprivation significantly reduced pain thresholds and tolerance scores in the experimental group. Additionally, the sympathovagal balance changed, characterized by a decrease in parasympathetic activation. Higher vagal withdrawal after food deprivation was associated with higher pain sensitivity in the experimental group. Furthermore, perceived unpleasantness and pain intensity increased for threshold and tolerance stimuli in the experimental group. We conclude that short-term food deprivation sensitized pain perception in healthy females. An imbalance in sympathovagal activation evoked by food deprivation accounted for this effect. Our results might be a pathogenic mechanism for the development of emotional difficulties associated with disturbed eating behavior. KW - short-term food deprivation KW - pain threshold KW - pain tolerance KW - sympathovagal balance Y1 - 2012 U6 - https://doi.org/10.1027/0269-8803/a000062 SN - 0269-8803 VL - 26 IS - 1 SP - 1 EP - 9 PB - Hogrefe CY - Göttingen ER - TY - JOUR A1 - Sereshki, L. E. A1 - Lomholt, M. A. A1 - Metzler, Ralf T1 - A solution to the subdiffusion-efficiency paradox inactive states enhance reaction efficiency at subdiffusion conditions in living cells JF - epl : a letters journal exploring the frontiers of physics N2 - Macromolecular crowding in living biological cells effects subdiffusion of larger biomolecules such as proteins and enzymes. Mimicking this subdiffusion in terms of random walks on a critical percolation cluster, we here present a case study of EcoRV restriction enzymes involved in vital cellular defence. We show that due to its so far elusive propensity to an inactive state the enzyme avoids non-specific binding and remains well-distributed in the bulk cytoplasm of the cell. Despite the reduced volume exploration capability of subdiffusion processes, this mechanism guarantees a high efficiency of the enzyme. By variation of the non-specific binding constant and the bond occupation probability on the percolation network, we demonstrate that reduced nonspecific binding are beneficial for efficient subdiffusive enzyme activity even in relatively small bacteria cells. Our results corroborate a more local picture of cellular regulation. Y1 - 2012 U6 - https://doi.org/10.1209/0295-5075/97/20008 SN - 0295-5075 VL - 97 IS - 2 PB - EDP Sciences CY - Mulhouse ER - TY - JOUR A1 - Rusconi, Marco A1 - Valleriani, Angelo A1 - Dunlop, John William Chapman A1 - Kurths, Jürgen A1 - Weinkamer, Richard T1 - Quantitative approach to the stochastics of bone remodeling JF - epl : a letters journal exploring the frontiers of physics N2 - During life bones constantly adapt their structure to their mechanical environment via a mechanically controlled process called bone remodeling. For trabecular bone, this process modifies the thickness of each trabecula leading occasionally to full resorption. We describe the irreversible dynamics of the trabecular thickness distribution (TTD) by means of a Markov chain discrete in space and time. By using thickness data from adult patients, we derive the transition probabilities in the chain. This allows a quantification, in terms of geometrical quantities, of the control of bone remodeling and thus to determine the evolution of the TTD with age. Y1 - 2012 U6 - https://doi.org/10.1209/0295-5075/97/28009 SN - 0295-5075 VL - 97 IS - 2 PB - EDP Sciences CY - Mulhouse ER - TY - JOUR A1 - Brietzke, Thomas Martin A1 - Mickler, Wulfhard A1 - Kelling, Alexandra A1 - Holdt, Hans-Jürgen T1 - Mono- and dinuclear ruthenium(II) 1,6,7,12-tetraazaperylene complexes JF - Dalton transactions : a journal of inorganic chemistry, including bioinorganic, organometallic, and solid-state chemistry N2 - We report the synthesis of free 1,6,7,12-tetraazaperylene (tape). Tape was obtained from 1,1'-bis-2,7-naphthyridine by potassium promoted cyclization followed by oxidation with air. Mono-and dinuclear ruthenium(II) 1,6,7,12-tetraazaperylene complexes of the general formulas [Ru(L-L)(2)(tape)](PF6)(2), [1] (PF6)(2)-[5](PF6)(2), and [{Ru(L-L)(2)}(2)(mu-tape)](PF6)(4), [6](PF6)(4)-[10](PF6)(4), with{L-L = phen, bpy, dmbpy (4,4'-dimethyl-2,2'-bipyridine), dtbbpy (4,4'-ditertbutyl-2,2'-bipyridine) and tmbpy (4,4' 5,5'-tetramethyl-2,2'- bipyridine)}, respectively, were synthesized. The X-ray structures of tape center dot 2CHCl(3) and the mononuclear complexes [Ru(bpy)(2)(tape)](PF6)(2)center dot 0.5CH(3)CN center dot 0.5toluene, [Ru(dmbpy)(2)(tape)] (PF6)(2)center dot 2toluene and [Ru(dtbbpy)(2)(tape)](PF6)(2) center dot 3acetone center dot 0.5H(2)O were solved. The UV-vis absorption spectra and the electrochemical behavior of the ruthenium(II) tape complexes were explored and compared with the data of the analogous dibenzoeilatin (dbneil), 2,2'-bipyrimidine (bpym) and tetrapyrido [3,2-a:2',3'-c:3 '',2''-h:2''',3'''-j] phenazin (tpphz) species. Y1 - 2012 U6 - https://doi.org/10.1039/c2dt11805j SN - 1477-9226 VL - 41 IS - 9 SP - 2788 EP - 2797 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Sun, Sheng-Yun A1 - Huang, Jin A1 - Meng, Min-Jie A1 - Lu, Jia-Hai A1 - Hocher, Berthold A1 - Liu, Kang-Li A1 - Yang, Qin-He A1 - Zhu, Xiao-Feng T1 - Improvement of lipid profile and reduction of body weight by Shan He Jian Fei Granules in high fat diet-induced obese rats JF - Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion N2 - Background: The goal was to study lipid profiles (TG, TC, LDL, HDL), effects on serum leptin, and fat tissue adiponectin, and resistin as well as body weight effects of Shan He Jian Fei Granules (SHJFG) in rats on a high fat diet. Methods: Rats were randomly divided into five groups: normal control group fed with normal fat diet, rats on high fat diet receiving low dosage, middle dosage, high dosage of Shan He Jian Fei Granules (SHJFG) as well as a high fat diet group receiving placebo. Rats were treated for 8 weeks. Body weight and naso-anal length of each rat were recorded and Lee's index was calculated. Serum TG, TC, LDL, HDL and leptin concentrations were analyzed. The gene expressions of adiponectin and resistin in adipose tissues were tested by RT-PCR. Results: Compared to the high-fat diet group, body weights, Lee's indexes, weight of fat tissues and serum TG, TC, LDL and leptin of SHJFG groups significantly decreased (p<0.05), whereas mRNA expressions of adiponectin and resistin of SHJFG groups significantly increased (p<0.05). Conclusions: SHJFG could significantly lower body weight and serum TG, TC, and LDL of obese rats. The effects of SHJFG in lowering leptin synthesis and raising mRNA expression of adiponectin and resistin in fat tissues may act as part of the mechanisms in lowering body weight of obese rats. Further studies are needed to demonstrate whether SHJFG may also reduce overall cardiovascular morbidity and mortality like other lipid lowering drugs. KW - obesity KW - high-fat diet KW - Shan He Jian Fei Granules (SHJFG) KW - lipid KW - adiponectin KW - resistin KW - leptin Y1 - 2012 SN - 1433-6510 VL - 58 IS - 1-2 SP - 81 EP - 87 PB - Clin Lab Publ., Verl. Klinisches Labor CY - Heidelberg ER - TY - JOUR A1 - Balci, Kubilay A1 - Yapar, G. A1 - Akkaya, Y. A1 - Akyuz, S. A1 - Koch, Andreas A1 - Kleinpeter, Erich T1 - A conformational analysis and vibrational spectroscopic investigation on 1,2-bis(o-carboxyphenoxy) ethane molecule JF - Vibrational spectroscopy : an international journal devoted to applications of infrared and raman spectroscopy N2 - The minima on the potential energy surface of 1,2-bis(o-carboxyphenoxy)ethane (CPE) molecule in its electronic ground state were searched by a molecular dynamics simulation performed with MM2 force field. For each of the found minimum-energy conformers, the corresponding equilibrium geometry, charge distribution, HOMO-LUMO energy gap, force field, vibrational normal modes and associated IR and Raman spectral data were determined by means of the density functional theory (DFT) based electronic structure calculations carried out by using B3LYP method and various Pople-style basis sets. The obtained theoretical data confirmed the significant effects of the intra- and inter-molecular hydrogen bonding interactions on the conformational structure, force field, and group vibrations of the molecule. The same data have also revealed that two of the determined stable conformers, both of which exhibit pseudo-crown structure, are considerably more favorable in energy to the others and accordingly provide the major contribution to the experimental spectra of CPE. In the light of the improved vibrational spectral data obtained within the "SQM FF" methodology and "Dual Scale Factors" approach for the monomer and dimer forms of these two conformers, a reliable assignment of the fundamental bands observed in the experimental room-temperature IR and Raman spectra of the molecule was given, and the sensitivities of its group vibrations to conformation, substitution and dimerization were discussed. KW - Glycol podands KW - Salicylic acid KW - IR and Raman spectra KW - SQM FF KW - Dual Scale Factors Y1 - 2012 U6 - https://doi.org/10.1016/j.vibspec.2011.11.011 SN - 0924-2031 VL - 58 IS - 1-2 SP - 27 EP - 43 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kühne, Ralph A1 - Huitema, George A1 - Carle, George T1 - Charging and billing in modern communications networks a comprehensive survey of the state of the art and future requirements JF - IEEE communications surveys & tutorials N2 - In mobile telecommunication networks the trend for an increasing heterogeneity of access networks, the convergence with fixed networks as well as with the Internet are apparent. The resulting future converged network with an expected wide variety of services and a possibly stiff competition between the different market participants as well as legal issues will bring about requirements for charging systems that demand for more flexibility, scalability and efficiency than is available in today's systems. This article surveys recent developments in charging and billing architectures comprising both standardisation work as well as research projects. The second main contribution of this article is a comparison of key features of these developments thus giving a list of essential charging and billing ingredients for tomorrow's communication and service environments. KW - charging KW - billing KW - accounting KW - communication network KW - architectures KW - requirements Y1 - 2012 U6 - https://doi.org/10.1109/SURV.2011.122310.000084 SN - 1553-877X VL - 14 IS - 1 SP - 170 EP - 192 PB - Inst. of Electr. and Electronics Engineers CY - Piscataway ER - TY - JOUR A1 - Oberhänsli, Roland A1 - Bousquet, Romain A1 - Candan, Osman A1 - Okay, Aral I. T1 - Dating subduction events in East Anatolia, Turkey JF - Turkish journal of earth sciences = Türk yerbilimleri dergisi N2 - Metamorphic studies in the cover sequences of the Bitlis complex allow the thermal evolution of the massif to be constrained using metamorphic index minerals. Regionally distributed metamorphic index minerals such as glaucophane, carpholite, relics of carpholite in chloritoid-bearing schists and pseudomorphs after aragonite in marbles record a LT-HP evolution:This demonstrates that the Bitlis complex was subducted and stacked to form a nappe complex during the closure of the Neo-Tethys. During late Cretaceous to Cenozoic evolution the Bitlis complex experienced peak metamorphism of 1.0-1.1 GPa at 350-400 degrees C. During the retrograde evolution temperatures remained below 460 degrees C. Ar-39/Ar-40 dating of white mica in different parageneses from the Bitlis complex reveals a 74-79 Ma (Campanian) date of peak metamorphism and rapid exhumation to an almost isothermal greenschist stage at 67-70 Ma (Maastrichtian). The HP Eocene flysch escaped the greenschist facies stage and were exhumed under very cold conditions. These single stage evolutions contrast with the multistage evolution reported further north from the Amassia-Stepanavan Suture in Armenia. Petrological investigations and isotopic dating show that the collision of Arabia with Eurasia resulted in an assemblage of different blocks derived from the northern as well as from the southern plate and a set of subduction zones producing HP rocks with diverse exhumation histories. KW - Bitlis complex KW - HP metamorphism KW - Ar dating KW - geodynamic evolution of SE Anatolia KW - subduction history Y1 - 2012 U6 - https://doi.org/10.3906/yer-1006-26 SN - 1300-0985 VL - 21 IS - 1 SP - 1 EP - 17 PB - Tübitak CY - Ankara ER - TY - JOUR A1 - Yin, Jian A1 - Linker, Torsten T1 - Recent advances in the stereoselective synthesis of carbohydrate 2-C-analogs JF - Organic & biomolecular chemistry : an international journal of synthetic, physical and biomolecular organic chemistry N2 - C-branched carbohydrates are of current interest for glycochemistry, are widely found in nature and serve as important subunits in many antibiotics, bacterial polysaccharides and macrolides. Among C-functionalized saccharides, 2-C-branched carbohydrates represent challenging structures for synthetic chemists, since in contrast to C-glycosides they are not easily accessible from glycosyl bromides or other simple precursors. In this perspective we want to summarize recent approaches to 2-C-branched carbohydrates over the past fifteen years. The two main strategies are based on ring-opening of 1,2-cyclopropanated carbohydrates by various reagents, as well as radical additions to glycals and further transformations, developed in our group. Both methods are characterized by high stereoselectivities and good yields and give access to a broad variety of functionalized carbohydrate 2-C-analogs. Y1 - 2012 U6 - https://doi.org/10.1039/c2ob06529k SN - 1477-0520 VL - 10 IS - 12 SP - 2351 EP - 2362 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Sarauli, David A1 - Riedel, Marc A1 - Wettstein, Christoph A1 - Hahn, Robert A1 - Stiba, Konstanze A1 - Wollenberger, Ursula A1 - Leimkühler, Silke A1 - Schmuki, Patrik A1 - Lisdat, Fred T1 - Semimetallic TiO2 nanotubes new interfaces for bioelectrochemical enzymatic catalysis JF - Journal of materials chemistry N2 - Different self-organized TiO2 nanotube structures are shown to represent new interfaces for the achievement of bioelectrochemical enzymatic catalysis involving redox proteins and enzymes without further surface modification or the presence of mediators. Y1 - 2012 U6 - https://doi.org/10.1039/c2jm16427b SN - 0959-9428 VL - 22 IS - 11 SP - 4615 EP - 4618 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Albrecht, Torsten A1 - Levermann, Anders T1 - Fracture field for large-scale ice dynamics JF - Journal of glaciology N2 - Recent observations and modeling studies emphasize the crucial role of fracture mechanics for the stability of ice shelves and thereby the evolution of ice sheets. Here we introduce a macroscopic fracture-density field into a prognostic continuum ice-flow model and compute its evolution incorporating the initiation and growth of fractures as well as their advection with two-dimensional ice flow. To a first approximation, fracture growth is assumed to depend on the spreading rate only, while fracture initiation is defined in terms of principal stresses. The inferred fracture-density fields compare well with observed elongate surface structures. Since crevasses and other deep-reaching fracture structures have been shown to influence the overall ice-shelf dynamics, we propose the fracture-density field introduced here be used as a measure for ice softening and decoupling of the ice flow in fracture-weakened zones. This may yield more accurate and realistic velocity patterns in prognostic simulations. Additionally, the memory of past fracture events links the calving front to the upstream dynamics. Thus the fracture-density field proposed here may be employed in fracture-based calving parameterizations. The aim of this study is to introduce the field and investigate which of the observed surface structures can be reproduced by the simplest physically motivated fracture source terms. Y1 - 2012 U6 - https://doi.org/10.3189/2012JoG11J191 SN - 0022-1430 SN - 1727-5652 VL - 58 IS - 207 SP - 165 EP - 176 PB - International Glaciological Society CY - Cambridge ER - TY - JOUR A1 - Seemüller, Anna A1 - Müller, E. M. A1 - Rösler, Frank T1 - EEG-power and -coherence changes in a unimodal and a crossmodal working memory task with visual and kinesthetic stimuli JF - International journal of psychophysiology N2 - We investigated EEG-power and EEG-coherence changes in a unimodal and a crossmodal matching-to-sample working memory task with either visual or kinesthetic stimuli. Angle-shaped trajectories were used as stimuli presented either as a moving dot on a screen or as a passive movement of a haptic device. Effects were evaluated during the different phases of encoding, maintenance, and recognition. Alpha power was modulated during encoding by the stimulus modality, and in crossmodal conditions during encoding and maintenance by the expected modality of the upcoming test stimulus. These power modulations were observed over modality-specific cortex regions. Systematic changes of coherence for crossmodal compared to unimodal tasks were not observed during encoding and maintenance but only during recognition. There, coherence in the theta-band increased between electrode sites over left central and occipital cortex areas in the crossmodal compared to the unimodal conditions. The results underline the importance of modality-specific representations and processes in unimodal and crossmodal working memory tasks. Crossmodal recognition of visually and kinesthetically presented object features seems to be related to a direct interaction of somatosensory/motor and visual cortex regions by means of long-range synchronization in the theta-band and such interactions seem to take place at the beginning of the recognition phase, i.e. when crossmodal transfer is actually necessary. KW - Visual representations KW - Kinesthetic representations KW - Synchronization KW - Crossmodal matching KW - Haptics Y1 - 2012 U6 - https://doi.org/10.1016/j.ijpsycho.2011.10.009 SN - 0167-8760 VL - 83 IS - 1 SP - 87 EP - 95 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schneider von Deimling, Thomas A1 - Meinshausen, Malte A1 - Levermann, Anders A1 - Huber, Veronika A1 - Frieler, Katja A1 - Lawrence, D. M. A1 - Brovkin, Victor T1 - Estimating the near-surface permafrost-carbon feedback on global warming JF - Biogeosciences N2 - Thawing of permafrost and the associated release of carbon constitutes a positive feedback in the climate system, elevating the effect of anthropogenic GHG emissions on global-mean temperatures. Multiple factors have hindered the quantification of this feedback, which was not included in climate carbon-cycle models which participated in recent model intercomparisons (such as the Coupled Carbon Cycle Climate Model Intercomparison Project - (CMIP)-M-4). There are considerable uncertainties in the rate and extent of permafrost thaw, the hydrological and vegetation response to permafrost thaw, the decomposition timescales of freshly thawed organic material, the proportion of soil carbon that might be emitted as carbon dioxide via aerobic decomposition or as methane via anaerobic decomposition, and in the magnitude of the high latitude amplification of global warming that will drive permafrost degradation. Additionally, there are extensive and poorly characterized regional heterogeneities in soil properties, carbon content, and hydrology. Here, we couple a new permafrost module to a reduced complexity carbon-cycle climate model, which allows us to perform a large ensemble of simulations. The ensemble is designed to span the uncertainties listed above and thereby the results provide an estimate of the potential strength of the feedback from newly thawed permafrost carbon. For the high CO2 concentration scenario (RCP8.5), 33-114 GtC (giga tons of Carbon) are released by 2100 (68% uncertainty range). This leads to an additional warming of 0.04-0.23 degrees C. Though projected 21st century permafrost carbon emissions are relatively modest, ongoing permafrost thaw and slow but steady soil carbon decomposition means that, by 2300, about half of the potentially vulnerable permafrost carbon stock in the upper 3 m of soil layer (600-1000 GtC) could be released as CO2, with an extra 1-4% being released as methane. Our results also suggest that mitigation action in line with the lower scenario RCP3-PD could contain Arctic temperature increase sufficiently that thawing of the permafrost area is limited to 9-23% and the permafrost-carbon induced temperature increase does not exceed 0.04-0.16 degrees C by 2300. Y1 - 2012 U6 - https://doi.org/10.5194/bg-9-649-2012 SN - 1726-4170 SN - 1726-4189 VL - 9 IS - 2 SP - 649 EP - 665 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Aichner, Bernhard A1 - Herzschuh, Ulrike A1 - Wilkes, Heinz A1 - Schulz, Hans-Martin A1 - Wang, Yongbo A1 - Plessen, Birgit A1 - Mischke, Steffen A1 - Diekmann, Bernhard A1 - Zhang, Chengjun T1 - Ecological development of Lake Donggi Cona, north-eastern Tibetan Plateau, since the late glacial on basis of organic geochemical proxies and non-pollen palynomorphs JF - Palaeogeography, palaeoclimatology, palaeoecology : an international journal for the geo-sciences N2 - Organic geochemical proxy data from surface sediment samples and a sediment core from Lake Donggi Cona were used to infer environmental changes on the northeastern Tibetan Plateau spanning the last 18.4 kyr. Long-chain n-alkanes dominate the aliphatic hydrocarbon fraction of the sediment extract from most surface sediment samples and the sediment core. Unsaturated mid-chain n-alkanes (nC(23:1) and nC(25:1)) have high abundances in some samples, especially in core samples from the late glacial and early Holocene. TOC contents, organic biomarker and non-pollen-palynomorph concentrations and results from organic petrologic analysis on selected samples suggest three major episodes in the history of Lake Donggi Cona. Before ca. 12.6 cal ka BP samples contain low amounts of organic matter due to cold and arid conditions during the late glacial. After 12.6 cal ka BP, relatively high contents of TOC and concentrations of Botryococcus fossils, as well as enhanced concentrations of mid-chain n-alkanes and n-alkenes suggest a higher primary and macrophyte productivity than at present This is supported by high contents of palynomorphs derived from higher plants and algae and was possibly triggered by a decrease of salinity and amelioration of climate during the early Holocene. Since 6.8 cal ka BP Lake Donggi Cona has been an oligotrophic freshwater lake. Proxy data suggest that variations in insolation drive ecological changes in the lake, with increased aquatic productivity during the early Holocene summer insolation maximum. Short-term drops of TOC contents or biomarker concentrations (at 9.9 cal ka BP, after 8.0 and between 3.5 and 1.7 cal ka BP) can possibly be related to relatively cool and dry episodes reported from other sites on the north-eastern Tibetan Plateau, which are hypothesized to occur in phase with Northern Hemisphere cooling events. KW - Biomarker KW - Holocene KW - n-alkanes KW - Total organic carbon KW - Organic matter KW - Macerals KW - Aquatic macrophytes Y1 - 2012 U6 - https://doi.org/10.1016/j.palaeo.2011.10.015 SN - 0031-0182 VL - 313 IS - 2 SP - 140 EP - 149 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Omranian, Nooshin A1 - Müller-Röber, Bernd A1 - Nikoloski, Zoran T1 - PageRank-based identification of signaling crosstalk from transcriptomics data the case of Arabidopsis thaliana JF - Molecular BioSystems N2 - The levels of cellular organization, from gene transcription to translation to protein-protein interaction and metabolism, operate via tightly regulated mutual interactions, facilitating organismal adaptability and various stress responses. Characterizing the mutual interactions between genes, transcription factors, and proteins involved in signaling, termed crosstalk, is therefore crucial for understanding and controlling cells' functionality. We aim at using high-throughput transcriptomics data to discover previously unknown links between signaling networks. We propose and analyze a novel method for crosstalk identification which relies on transcriptomics data and overcomes the lack of complete information for signaling pathways in Arabidopsis thaliana. Our method first employs a network-based transformation of the results from the statistical analysis of differential gene expression in given groups of experiments under different signal-inducing conditions. The stationary distribution of a random walk (similar to the PageRank algorithm) on the constructed network is then used to determine the putative transcripts interrelating different signaling pathways. With the help of the proposed method, we analyze a transcriptomics data set including experiments from four different stresses/signals: nitrate, sulfur, iron, and hormones. We identified promising gene candidates, downstream of the transcription factors (TFs), associated to signaling crosstalk, which were validated through literature mining. In addition, we conduct a comparative analysis with the only other available method in this field which used a biclustering-based approach. Surprisingly, the biclustering-based approach fails to robustly identify any candidate genes involved in the crosstalk of the analyzed signals. We demonstrate that our proposed method is more robust in identifying gene candidates involved downstream of the signaling crosstalk for species for which large transcriptomics data sets, normalized with the same techniques, are available. Moreover, unlike approaches based on biclustering, our approach does not rely on any hidden parameters. Y1 - 2012 U6 - https://doi.org/10.1039/c2mb05365a SN - 1742-206X VL - 8 IS - 4 SP - 1121 EP - 1127 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Tronicke, Jens A1 - Paasche, Hendrik A1 - Böniger, Urs T1 - Crosshole traveltime tomography using particle swarm optimization a near-surface field example JF - Geophysics N2 - Particle swarm optimization (PSO) is a relatively new global optimization approach inspired by the social behavior of bird flocking and fish schooling. Although this approach has proven to provide excellent convergence rates in different optimization problems, it has seldom been applied to inverse geophysical problems. Until today, published geophysical applications mainly focus on finding an optimum solution for simple, 1D inverse problems. We have applied PSO-based optimization strategies to reconstruct 2D P-wave velocity fields from crosshole traveltime data sets. Our inversion strategy also includes generating and analyzing a representative ensemble of acceptable models, which allows us to appraise uncertainty and nonuniqueness issues. The potential of our strategy was tested on field data collected at a well-constrained test site in Horstwalde, Germany. At this field site, the shallow subsurface mainly consists of sand- and gravel-dominated glaciofluvial sediments, which, as known from several boreholes and other geophysical experiments, exhibit some well-defined layering at the scale of our crosshole seismic data. Thus, we have implemented a flexible, layer-based model parameterization, which, compared with standard cell-based parameterizations, allows for significantly reducing the number of unknown model parameters and for efficiently implementing a priori model constraints. Comparing the 2D velocity fields resulting from our PSO strategy to independent borehole and direct-push data illustrated the benefits of choosing an efficient global optimization approach. These include a straightforward and understandable appraisal of nonuniqueness issues as well as the possibility of an improved and also more objective interpretation. Y1 - 2012 U6 - https://doi.org/10.1190/GEO2010-0411.1 SN - 0016-8033 SN - 1942-2156 VL - 77 IS - 1 SP - R19 EP - R32 PB - Society of Exploration Geophysicists CY - Tulsa ER - TY - JOUR A1 - Zaklan, Aleksandar A1 - Cullmann, Astrid A1 - Neumann, Anne A1 - von Hirschhausen, Christian T1 - The globalization of steam coal markets and the role of logistics an empirical analysis JF - Energy economics N2 - In this paper, we provide a comprehensive multivariate cointegration analysis of three parts of the steam coal value chain - export, transport and import prices. The analysis is based on a rich dataset of international coal prices: in particular, we combine data on steam coal prices with freight rates, covering the period December 2001 until August 2009 at weekly frequency. We then test whether the demand and supply side components of steam coal trade are consistently integrated with one another. In addition, export and import prices as well as freight rates for individual trading routes, across regions and globally are combined. We find evidence of significant yet incomplete integration. We also find heterogeneous short-term dynamics of individual markets. Furthermore, we examine whether logistics enter coal price dynamics through transportation costs, which are mainly determined by oil prices. Our results suggest that this is generally not the case. KW - Steam coal KW - Market integration KW - Multivariate cointegration Y1 - 2012 U6 - https://doi.org/10.1016/j.eneco.2011.03.001 SN - 0140-9883 VL - 34 IS - 1 SP - 105 EP - 116 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Khelifi, N. A1 - Sarnthein, M. A1 - Naafs, B. D. A. T1 - Technical note: Late Pliocene age control and composite depths at ODP Site 982, revisited JF - CLIMATE OF THE PAST N2 - Ocean Drilling Program (ODP) Site 982 provided a key sediment section at Rockall Plateau for reconstructing northeast Atlantic paleoceanography and monitoring benthic delta O-18 stratigraphy over the late Pliocene to Quaternary onset of major Northern Hemisphere glaciation. A renewed hole-specific inspection of magnetostratigraphic reversals and the addition of epibenthic delta O-18 records for short Pliocene sections in holes 982A, B, and C, crossing core breaks in the delta O-18 record published for Hole 982B, now imply a major revision of composite core depths. After tuning to the orbitally tuned reference record LR04, the new composite delta O-18 record results in a hiatus, where the Kaena magnetic subchron might have been lost, and in a significant age reduction for all proxy records by 130 to 20 ky over the time span 3.2-2.7 million years ago (Ma). Our study demonstrates the general significance of reliable composite-depth scales and delta O-18 stratigraphies in ODP sediment records for generating ocean-wide correlations in paleoceanography. The new concept of age control makes the late Pliocene trends in SST (sea surface temperature) and atmospheric pCO(2) at Site 982 more consistent with various paleoclimate trends published from elsewhere in the North Atlantic. Y1 - 2012 U6 - https://doi.org/10.5194/cp-8-79-2012 SN - 1814-9324 VL - 8 IS - 1 SP - 79 EP - 87 PB - COPERNICUS GESELLSCHAFT MBH CY - GOTTINGEN ER - TY - JOUR A1 - Herbert, Beate M. A1 - Herbert, Cornelia A1 - Pollatos, Olga A1 - Weimer, Katja A1 - Enck, Paul A1 - Sauer, Helene A1 - Zipfel, Stephan T1 - Effects of short-term food deprivation on interoceptive awareness, feelings and autonomic cardiac activity JF - Biological psychology N2 - The perception of internal bodily signals (interoception) plays a relevant role for emotion processing and feelings. This study investigated changes of interoceptive awareness and cardiac autonomic activity induced by short-term food deprivation and its relationship to hunger and affective experience. 20 healthy women were exposed to 24 h of food deprivation in a controlled setting. Interoceptive awareness was assessed by using a heartbeat tracking task. Felt hunger, cardiac autonomic activity, mood and subjective appraisal of interoceptive sensations were assessed before and after fasting. Results show that short-term fasting intensifies interoceptive awareness, not restricted to food cues, via changes of autonomic cardiac and/or cardiodynamic activity. The increase of interoceptive awareness was positively related to felt hunger. Additionally, the results demonstrate the role of cardiac vagal activity as a potential index of emotion related self-regulation, for hunger, mood and the affective appraisal of interoceptive signals during acute fasting. KW - Interoceptive awareness KW - Hunger KW - Autonomic activity KW - Food deprivation KW - Self-regulation KW - Eating disorders Y1 - 2012 U6 - https://doi.org/10.1016/j.biopsycho.2011.09.004 SN - 0301-0511 VL - 89 IS - 1 SP - 71 EP - 79 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Telezhinsky, Igor O. A1 - Dwarkadas, Vikram V. A1 - Pohl, Martin T1 - Particle spectra from acceleration at forward and reverse shocks of young Type Ia Supernova Remnants JF - Astroparticle physics N2 - We study cosmic-ray acceleration in young Type Ia Supernova Remnants (SNRs) by means of test-particle diffusive shock acceleration theory and 1-D hydrodynamical simulations of their evolution. In addition to acceleration at the forward shock, we explore the particle acceleration at the reverse shock in the presence of a possible substantial magnetic field, and consequently the impact of this acceleration on the particle spectra in the remnant. We investigate the time evolution of the spectra for various time-dependent profiles of the magnetic field in the shocked region of the remnant. We test a possible influence on particle spectra of the Alfvenic drift of scattering centers in the precursor regions of the shocks. In addition, we study the radiation spectra and morphology in a broad band from radio to gamma-rays. It is demonstrated that the reverse shock contribution to the cosmic-ray particle population of young Type la SNRs may be significant, modifying the spatial distribution of particles and noticeably affecting the volume-integrated particle spectra in young SNRs. In particular spectral structures may arise in test-particle calculations that are often discussed as signatures of non-linear cosmic-ray modification of shocks. Therefore, the spectrum and morphology of emission, and their time evolution, differ from pure forward-shock solutions. KW - Supernova Remnants KW - Cosmic rays KW - Cosmic-ray acceleration KW - Hydrodynamics KW - Forward and reverse shocks Y1 - 2012 U6 - https://doi.org/10.1016/j.astropartphys.2011.10.001 SN - 0927-6505 VL - 35 IS - 6 SP - 300 EP - 311 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Sarauli, David A1 - Xu, Chenggang A1 - Dietzel, Birgit A1 - Stiba, Konstanze A1 - Leimkühler, Silke A1 - Schulz, Burkhard A1 - Lisdat, Fred T1 - Thin films of substituted polyanilines interactions with biomolecular systems JF - Soft matter N2 - We use substituted polyanilines for the construction of new polymer electrodes for interaction studies with the redox protein cytochrome c (cyt c) and the enzyme sulfite oxidase (SO). For these purposes four different polyaniline copolymers are chemically synthesized. Three of them are copolymers, containing 2-methoxyaniline-5-sulfonic acid with variable ratios of aniline; the fourth copolymer consists of 3-amino-benzoic acid and aniline. The results show that all polymers are suitable for being immobilized as thin stable films on gold wire and indium tin oxide (ITO) electrode surfaces from DMSO solution. This can be demonstrated by cyclic voltammetry and UV-Vis spectroscopy measurements. Moreover, cyt c can be electrochemically detected not only in solution, but also immobilized on top of the polymer films. Furthermore, the appearance of a significant catalytic current has been demonstrated for the sulfonated polyanilines, when the polymer-coated protein electrode is being measured upon addition of sulfite oxidase, confirming the establishment of a bioanalytical signal chain. Best results have been obtained for the polymer with highest sulfonation grade. The redox switching of the polymer by the enzymatic reaction can also be analyzed by following the spectral properties of the polymer electrode. Y1 - 2012 U6 - https://doi.org/10.1039/c2sm07261k SN - 1744-683X VL - 8 IS - 14 SP - 3848 EP - 3855 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Stede, Manfred A1 - Peldszus, Andreas T1 - The role of illocutionary status in the usage conditions of causal connectives and in coherence relations JF - Journal of pragmatics : an interdisciplinary journal of language studies N2 - The meaning of linguistic connectives has often been characterized in terms of their position in a bipartite (semantic, pragmatic) or a tripartite (content, epistemic, speech act) structure of domains, depending on what kinds of entities are being connected (largely: propositions or speech acts). This paper argues that a more fine-grained analysis can be achieved by directing some more attention to the characterization of the entities being related. We propose an inventory of categories of illocutionary status for labelling the spans that are being connected. On this basis, the distinction between the content and the epistemic domain, in particular, can be made more explicit. Focusing on the group of causal connectives in German, we conducted a corpus annotation study from which we derived distinct pragmatic 'usage profiles' of the most frequent causal connectives. Finally, we offer some suggestions on the role of illocutions in relation-based accounts of discourse structure. KW - Connective KW - Coherence relation KW - Speech act KW - Illocutionary force Y1 - 2012 U6 - https://doi.org/10.1016/j.pragma.2012.01.004 SN - 0378-2166 VL - 44 IS - 2 SP - 214 EP - 229 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - König, Tobias A1 - Sekhar, Y. Nataraja A1 - Santer, Svetlana T1 - Surface plasmon nanolithography impact of dynamically varying near-field boundary conditions at the air-polymer interface JF - Journal of materials chemistry N2 - It is well-known that surface plasmon generated near fields of suitably irradiated metal nano-structures can induce a patterning in an azobenzene-modified photosensitive polymer film placed on top. The change in the topography usually follows closely and permanently the underlying near field intensity pattern. With this approach, one can achieve a multitude of morphologies by additionally changing light intensity, polarization and the kind of metal used for nano-structuring. In this paper, we demonstrate that below a critical value of the polymer film thickness, the receding polymer material induces a change in refractive index of the glass-metal-polymer system, modifying the near field intensity distribution and causing a back-reaction on the flow of polymer material. This has a profound influence on the smallest size of topographical features that can be imprinted into the polymer. Y1 - 2012 U6 - https://doi.org/10.1039/c2jm15864g SN - 0959-9428 VL - 22 IS - 13 SP - 5945 EP - 5950 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Haakh, Harald Richard A1 - Henkel, Carsten T1 - Magnetic near fields as a probe of charge transport in spatially dispersive conductors JF - The European physical journal : B, Condensed matter and complex systems N2 - We calculate magnetic field fluctuations above a conductor with a nonlocal response (spatial dispersion) and consider a large range of distances. The cross-over from ballistic to diffusive charge transport leads to a reduced noise spectrum at distances below the electronic mean free path, as compared to a local description. We also find that the mean free path provides a lower limit to the correlation (coherence) length of the near field fluctuations. The short-distance behaviour is common to a wide range of materials, including semiconductors and superconductors. Our discussion is aimed at atom chip experiments where spin-flip transitions give access to material properties with mesoscopic spatial resolution. The results also hint at fundamental limits to the coherent operation of miniaturised atom traps and matter-wave interferometers. Y1 - 2012 U6 - https://doi.org/10.1140/epjb/e2011-20567-1 SN - 1434-6028 VL - 85 IS - 1 PB - Springer CY - New York ER - TY - JOUR A1 - Frisch, Johannes A1 - Schubert, Marcel A1 - Preis, Eduard A1 - Rabe, Jürgen P. A1 - Neher, Dieter A1 - Scherf, Ullrich A1 - Koch, Norbert T1 - Full electronic structure across a polymer heterojunction solar cell JF - Journal of materials chemistry N2 - We correlate the morphology and energy level alignment of bilayer structures comprising the donor poly(3-hexylthiophene) (P3HT) and the acceptor polyfluorene copolymer poly(9,90dialklylfluorene-alt-4,7-bis(2,5-thiendiyl)-2,1,3-benzothiadiazole) (PFTBTT) with the performance of these bilayers in organic photovoltaic cells (OPVCs). The conducting polymer poly(ethylenedioxythiophene): poly (styrenesulfonate) (PEDT:PSS) was used as the bottom electrode and Ca as the top electrode. Ultraviolet photoelectron spectroscopy (UPS) revealed that notable interface dipoles occur at all interfaces across the OPVC structure, highlighting that vacuum level alignment cannot reliably be used to estimate the electronic properties for device design. Particularly the effective electrode work function values (after contact formation with the conjugated polymers) differ significantly from those of the pristine electrode materials. Chemical reactions between PEDT: PSS and P3HT on the one hand and Ca and PFTBTT on the other hand are identified as cause for the measured interface dipoles. The vacuum level shift between P3HT and PFTBTT is related to mutual energy level pinning at gap states. Annealing induced morphological changes at the P3HT/PFTBTT interface increased the efficiency of OPVCs, while the electronic structure was not affected by thermal treatment. Y1 - 2012 U6 - https://doi.org/10.1039/c1jm14968g SN - 0959-9428 VL - 22 IS - 10 SP - 4418 EP - 4424 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Costa, Alexandre Cunha A1 - Bronstert, Axel A1 - Kneis, David T1 - Probabilistic flood forecasting for a mountainous headwater catchment using a nonparametric stochastic dynamic approach JF - Hydrological sciences journal = Journal des sciences hydrologiques N2 - Hydrological models are commonly used to perform real-time runoff forecasting for flood warning. Their application requires catchment characteristics and precipitation series that are not always available. An alternative approach is nonparametric modelling based only on runoff series. However, the following questions arise: Can nonparametric models show reliable forecasting? Can they perform as reliably as hydrological models? We performed probabilistic forecasting one, two and three hours ahead for a runoff series, with the aim of ascribing a probability density function to predicted discharge using time series analysis based on stochastic dynamics theory. The derived dynamic terms were compared to a hydrological model, LARSIM. Our procedure was able to forecast within 95% confidence interval 1-, 2- and 3-h ahead discharge probability functions with about 1.40 m(3)/s of range and relative errors (%) in the range [-30; 30]. The LARSIM model and the best nonparametric approaches gave similar results, but the range of relative errors was larger for the nonparametric approaches. KW - streamflow probabilistic forecasting KW - time series analysis KW - stochastic dynamical systems KW - parametric and nonparametric comparison Y1 - 2012 U6 - https://doi.org/10.1080/02626667.2011.637043 SN - 0262-6667 VL - 57 IS - 1 SP - 10 EP - 25 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Fay, Doris A1 - Sonnentag, Sabine T1 - Within-person fluctuations of proactive behavior how affect and experienced competence regulate work behavior JF - Human performance N2 - This article studies proactive work behavior from a within-person perspective. Building on the broaden-and-build model and the mood-as-information approach, we hypothesized that negative trait affect and positive state affect predict the relative time spent on proactive behavior. Furthermore, based on self-determination theory we argued that persons want to feel competent and that proactive behavior is one way to experience competence. In an experience-sampling study, 52 employees responded to surveys 3 times a day for 5 days. Hierarchical linear modeling confirmed the hypotheses on trait and state affect. Analyses furthermore showed that although a higher level of experienced competence at core task activities was associated with a subsequent increase in time spent on these activities, low experienced competence predicted an increase in time spent on proactive behavior. Y1 - 2012 U6 - https://doi.org/10.1080/08959285.2011.631647 SN - 0895-9285 VL - 25 IS - 1 SP - 72 EP - 93 PB - Routledge, Taylor & Francis Group CY - Philadelphia ER - TY - JOUR A1 - Xie, Zai-Lai A1 - Xu, Hai-Bing A1 - Gessner, Andre A1 - Kumke, Michael Uwe A1 - Priebe, Magdalena A1 - Fromm, Katharina M. A1 - Taubert, Andreas T1 - A transparent, flexible, ion conductive, and luminescent PMMA ionogel based on a Pt/Eu bimetallic complex and the ionic liquid [Bmim][N(Tf)(2)] JF - Journal of materials chemistry N2 - Transparent, ion-conducting, luminescent, and flexible ionogels based on the room temperature ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl) imide [Bmim][N(Tf)(2)], a PtEu2 chromophore, and poly(methylmethacrylate) (PMMA) have been prepared. The thermal stability of the PMMA significantly increases with IL incorporation. In particular, the onset weight loss observed at ca. 229 degrees C for pure PMMA increases to 305 degrees C with IL addition. The ionogel has a high ionic conductivity of 10(-3) S cm(-1) at 373 K and exhibits a strong emission in the red with a long average luminescence decay time of tau = 890 mu s. The resulting material is a new type of soft hybrid material featuring useful thermal, optical, and ion transport properties. Y1 - 2012 U6 - https://doi.org/10.1039/c2jm15862k SN - 0959-9428 VL - 22 IS - 16 SP - 8110 EP - 8116 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Koeth, Anja A1 - Tiersch, Brigitte A1 - Appelhans, Dietmar A1 - Gradzielski, Michael A1 - Cölfen, Helmut A1 - Koetz, Joachim T1 - Synthesis of Core-Shell Gold Nanoparticles with Maltose-Modified Poly(Ethyleneimine) JF - Journal of dispersion science and technology N2 - The synthesis of ultrafine gold nanoparticles in presence of maltose-modified hyperbranched poly(ethyleneimines) (PEI) is described. The polymer acted as both a reducing and stabilising agent in the particle formation process. The nanoparticles were characterized by means of dynamic light scattering (DLS), transmission electron microscopy (TEM), analytical ultracentrifugation (AUC), small-angle x-ray scattering (SAXS), and small-angle neutron scattering (SANS). The mechanism of nanoparticle formation can be described in two steps. The reduction process of the Au3+ ions located in the inner coil region of the hyperbranched PEI led to the formation of a compact gold core, and is accompanied by a collapse of the polymer coil. Therefore, in the subsequent reduction process a gold-polymer hybrid shell is formed. By using the PEI of higher molar mass, core-shell gold nanoparticles of about 3.6 nm size with a more narrow size distribution and special fluorescence behavior could be synthesized. KW - Gold nanoparticles KW - gold-polymer hybrid shell KW - maltose-modified poly(ethyleneimine) Y1 - 2012 U6 - https://doi.org/10.1080/01932691.2010.530084 SN - 0193-2691 VL - 33 IS - 1-3 SP - 52 EP - 60 PB - Taylor & Francis Group CY - Philadelphia ER - TY - JOUR A1 - Sumpf, Bernd A1 - Maiwald, Martin A1 - Muller, Andre A1 - Ginolas, Arnim A1 - Haeusler, Karl A1 - Erbert, Goetz A1 - Traenkle, Guenther T1 - Reliable operation for 14 500 h of a wavelength-stabilized Diode Laser System on a Microoptical Bench at 671 nm JF - IEEE transactions on components, packaging and manufacturing technology N2 - Reliability tests for wavelength-stabilized compact diode laser systems emitting at 671 nm are presented. The devices were mounted on microoptical benches with the dimensions of 13 mm x 4 mm. Reflecting Bragg gratings were used for wavelength stabilization and emission width narrowing. The reliability tests were performed at 25 degrees C and at an output power up to 10 mW per micrometer stripe width of the gain medium. Reliable operation could be demonstrated over a test time up to 14 500 h at an output power up to 1.0 W. Environmental tests using random vibrations with acceleration up to 29 g were performed without deterioration of the devices. KW - High-power lasers KW - laser resonators KW - Raman spectroscopy KW - reliability KW - semiconductor lasers Y1 - 2012 U6 - https://doi.org/10.1109/TCPMT.2011.2171342 SN - 2156-3950 VL - 2 IS - 1 SP - 116 EP - 121 PB - Inst. of Electr. and Electronics Engineers CY - Piscataway ER - TY - JOUR A1 - Koss, Michael T1 - The role of governments in legislative agenda setting JF - West European politics Y1 - 2012 U6 - https://doi.org/10.1080/01402382.2011.648482 SN - 0140-2382 VL - 35 IS - 2 SP - 436 EP - 437 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Goebel, Ronald A1 - White, Robin J. A1 - Titirici, Maria-Magdalena A1 - Taubert, Andreas T1 - Carbon-based ionogels tuning the properties of the ionic liquid via carbon-ionic liquid interaction JF - Physical chemistry, chemical physics : a journal of European Chemical Societies N2 - The behavior of two ionic liquids (ILs), 1-ethyl-3-methylimidazolium dicyanamide [Emim][DCA] and 1-ethyl-3-methylimidazolium triflate [Emim][TfO], in (meso) porous carbonaceous hosts was investigated. Prior to IL incorporation into the host, the carbon matrix was thermally annealed between 180 and 900 degrees C to control carbon condensation and surface chemistry. The resulting materials have an increasing "graphitic'' carbon character with increasing treatment temperature, reflected in a modified behavior of the ILs when impregnated into the carbon host. The two ILs show significant changes in the thermal behavior as measured from differential scanning calorimetry; these changes can be assigned to anion-pi interaction between the IL anions and the pore wall surfaces of these flexible carbonaceous support materials. Y1 - 2012 U6 - https://doi.org/10.1039/c2cp23929a SN - 1463-9076 VL - 14 IS - 17 SP - 5992 EP - 5997 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Razzaq, Muhammad Yasar A1 - Behl, Marc A1 - Frank, Ute A1 - Koetz, Joachim A1 - Szczerba, Wojciech A1 - Lendlein, Andreas T1 - Oligo(omega-pentadecalactone) decorated magnetic nanoparticles JF - Journal of materials chemistry N2 - Hybrid magnetic nanoparticles (mgNP) with a magnetite core diameter of 10 +/- 1 nm surface functionalized with oligo(omega-pentadecalactone) (OPDL) oligomers with M-n between 1300 and 3300 g mol(-1) could be successfully prepared having OPDL grafted from 200 mg g(-1) to 2170 mg g(-1). The particles are dispersible in chloroform resulting in stable suspensions. Magnetic response against an external magnetic field proved the superparamagnetic nature of the particles with a low coercivity (B-c) value of 297 mu T. The combination of the advantageous superparamagnetism of the mgNP with the exceptional stability of OPDL makes these novel hybrid mgNP promising candidates as multifunctional building blocks for magnetic nanocomposites with tunable physical properties. Y1 - 2012 U6 - https://doi.org/10.1039/c2jm16146j SN - 0959-9428 VL - 22 IS - 18 SP - 9237 EP - 9243 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Neumann, Mike A1 - Noeske, Robert A1 - Taubert, Andreas A1 - Tiersch, Brigitte A1 - Strauch, Peter T1 - Highly structured, biomorphous beta-SiC with high specific surface area from Equisetaceae JF - Journal of materials chemistry N2 - Mesoporous, highly structured silicon carbide (beta-SiC) was synthesised from renewable plant materials (two Equisetaceae species) in a one-step carbothermal process at remarkably low temperatures down to 1200 degrees C. The SiC precursor is a silicon-carbon mixture with finely dispersed carbon prepared by pyrolysis of the organic plant matrix. Yields are 3 to 100% (omega(Si/Si) related to the silicon deposited in the plant material), depending on reaction temperature and time. IR spectroscopy, X-ray diffraction, and nitrogen sorption prove the formation of high-purity beta-SiC with minor inorganic impurities after purification and a high specific surface area of up to 660 m(2) g(-1). Scanning electron microscopy shows that the plant morphology is maintained in the final SiC. Sedimentation analysis finds a mean particle size (diameters d(50)) of 20 mu m. Y1 - 2012 U6 - https://doi.org/10.1039/c2jm30253e SN - 0959-9428 VL - 22 IS - 18 SP - 9046 EP - 9051 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Schmidt, Bernd A1 - Elizarov, Nelli T1 - Selective arene functionalization through sequential oxidative and non-oxidative Heck reactions JF - Chemical communications N2 - A sequence of acetamide directed oxidative Heck reaction and deacetylation-diazotation-Heck coupling allows the traceless removal of the acetamide group and its dual exploitation as a catalyst directing group and a leaving group. Y1 - 2012 U6 - https://doi.org/10.1039/c2cc30752a SN - 1359-7345 VL - 48 IS - 36 SP - 4350 EP - 4352 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Guetschow, Johannes A1 - Nesme, Vincent A1 - Werner, Reinhard F. T1 - Self-similarity of cellular automata on abelian groups JF - Journal of cellular automata N2 - It is well known that the spacetime diagrams of some cellular automata have a self-similar fractal structure: for instance Wolfram's rule 90 generates a Sierpinski triangle. Explaining the self-similarity of the spacetime diagrams of cellular automata is a well-explored topic, but virtually all of the results revolve around a special class of automata, whose typical features include irreversibility, an alphabet with a ring structure, a global evolution that is a ring homomorphism, and a property known as (weakly) p-Fermat. The class of automata that we study in this article has none of these properties. Their cell structure is weaker, as it does not come with a multiplication, and they are far from being p-Fermat, even weakly. However, they do produce self-similar spacetime diagrams, and we explain why and how. KW - fractal KW - abelian group KW - linear cellular automaton KW - substitution system KW - self-similarity Y1 - 2012 SN - 1557-5969 VL - 7 IS - 2 SP - 83 EP - 113 PB - Old City Publishing Science CY - Philadelphia ER - TY - JOUR A1 - Keehner, Madeleine A1 - Fischer, Martin H. T1 - Unusual bodies, uncommon behaviors individual and group differences in embodied cognition in spatial tasks JF - Spatial cognition and computation N2 - This editorial introduces a set of papers on differential embodiment in spatial tasks. According to the theoretical notion of embodied cognition, our experiences of acting in the world, and the constraints of our sensory and motor systems, strongly shape our cognitive functions. In the current set of papers, the authors were asked to particularly consider idiosyncratic or differential embodied cognition in the context of spatial tasks and processes. In each contribution, differential embodiment is considered from one of two complementary perspectives: either by considering unusual individuals, who have atypical bodies or uncommon experiences of interacting with the world; or by exploring individual differences in the general population that reflect the naturally occurring variability in embodied processes. Our editorial summarizes the contributions to this special issue and discusses the insights they offer. We conclude from this collection of papers that exploring differences in the recruitment and involvement of embodied processes can be highly informative, and can add an extra dimension to our understanding of spatial cognitive functions. Taking a broader perspective, it can also shed light on important theoretical and empirical questions concerning the nature of embodied cognition per se. KW - embodied cognition KW - spatial cognition KW - individual differences KW - spatial ability KW - strategy KW - expertise KW - mental representation Y1 - 2012 U6 - https://doi.org/10.1080/13875868.2012.659303 SN - 1387-5868 VL - 12 IS - 2-3 SP - 71 EP - 82 PB - Taylor & Francis Group CY - Philadelphia ER - TY - JOUR A1 - Zhong, Qi A1 - Metwalli, Ezzeldin A1 - Kaune, Gunar A1 - Rawolle, Monika A1 - Bivigou Koumba, Achille Mayelle A1 - Laschewsky, André A1 - Papadakis, Christine M. A1 - Cubitt, Robert A1 - Müller-Buschbaum, Peter T1 - Switching kinetics of thin thermo-responsive hydrogel films of poly(monomethoxy-diethyleneglycol-acrylate) probed with in situ neutron reflectivity JF - Soft matter N2 - The switching kinetics of thin thermo-responsive hydrogel films of poly(monomethoxy-diethyleneglycol-acrylate) (PMDEGA) are investigated. Homogeneous and smooth PMDEGA films with a thickness of 35.9 nm are prepared on silicon substrates by spin coating. As probed with white light interferometry, PMDEGA films with a thickness of 35.9 nm exhibit a phase transition temperature of the lower critical solution temperature (LCST) type of 40 degrees C. In situ neutron reflectivity is performed to investigate the thermo-responsive behavior of these PMDEGA hydrogel films in response to a sudden thermal stimulus in deuterated water vapor atmosphere. The collapse transition proceeds in a complex way which can be seen as three steps. The first step is the shrinkage of the initially swollen film by a release of water. In the second step the thickness remains constant with water molecules embedded in the film. In the third step, perhaps due to a conformational rearrangement of the collapsed PMDEGA chains, water is reabsorbed from the vapor atmosphere, thereby giving rise to a relaxation process. Both the shrinkage and relaxation processes can be described by a simple model of hydrogel deswelling. Y1 - 2012 U6 - https://doi.org/10.1039/c2sm25401h SN - 1744-683X VL - 8 IS - 19 SP - 5241 EP - 5249 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Krause, E. Tobias A1 - Liesenjohann, Thilo T1 - Predation pressure and food abundance during early life alter risk-taking behaviour and growth of guppies (Poecilia reticulata) JF - Behaviour : an international journal of behavioural biology N2 - The trade-off between predation risk and the need to feed is one of the major constraints animals have to cope with. Virtually all animals have a higher risk of being preyed upon when being active (e.g., searching for food or mating partners), compared with being inactive (e.g., staying at their burrows, nests, etc.). Yet, staying safe leads to a higher risk of starvation and may reduce reproductive success and body growth. Hence selection on behaviour optimizing the search, handling and digestion of food while avoiding the risk of predation is strong and should lead to strategies maximising survival chances and inclusive fitness. These facts call for integrative studies manipulating both, abundance of food and predation risk in a factorial set up, analysing the effects of both factors on behaviour and physiological parameters. We present results of a 2 x 2 factorial experiment, manipulating risk of predation and food abundance in guppies. We found that the two factors have an additive effect on body growth, but that predation risk by a pike cichlid is the main factor affecting the expression of behavioural strategies in guppies. Low food availability and high predation risk led to lower body growth. High predation risk affected swimming depth and risk sensitivity of guppies and might represent adaptive behavioural changes to the environmental context experienced in early life. Our study shows that integrative studies, analysing multiple interdependent and interconnected factors in the wild and in the lab are needed to further understand animal behaviour and development. KW - predation KW - food abundance KW - nutritional stress KW - risk taking KW - early development KW - developmental stress KW - guppy KW - Poecilia reticulata Y1 - 2012 U6 - https://doi.org/10.1163/156853912X623748 SN - 0005-7959 VL - 149 IS - 1 SP - 1 EP - 14 PB - Brill CY - Leiden ER - TY - JOUR A1 - Janewa, Vanessa Schönfeld A1 - Ghosh, Arnab A1 - Scheffler, Christiane T1 - Comparison of BMI and percentage of body fat of Indian and German children and adolescents JF - Journal of biological and clinical anthropology : Anthropologischer Anzeiger ; Mitteilungsorgan der Gesellschaft für Anthropologie N2 - Today, serious health problems as overweight and obesity are not just constricted to the developed world, but also increase in the developing countries (Prentice 2006, Ramachandram et al. 2002). Focusing on this issue, BMI and percentage of body fat were compared in 2094 schoolchildren from two cross-sectional studies from India and Germany investigated in 2008 and 2009. The German children are in all age groups significantly taller, whereas the Indian children show higher values in BMI (e.g. 12 years: Indian: around 22 kg/m(2); German: around 19 kg/m(2)) and in the percentage of body fat (e.g. 12 years: Indian: around 27 %; German: around 18-20%) in most of the investigated age groups. The Indian children have significantly higher BMI between 10 and 13 (boys) respectively 14 years (girls). Indian children showed significant higher percentage of body fat between 10 and 15 years (boys) and between 8 and 16 years (girls). The difference in overweight between Indian and German children was strongest at 11 (boys) and 12 (girls) years: 70 % of the Indian but 20% of the German children were classified as overweight. In countries such as India that undergo nutritional transition, a rapid increase in obesity and overweight is observed. In contrast to the industrialized countries, the risk of overweight in developing countries is associated with high socioeconomic status. Other reasons of the rapid increase of overweight in the developing countries caused by different environmental or genetic factors are discussed. KW - Overweight KW - school children KW - industrial and developing countries Y1 - 2012 U6 - https://doi.org/10.1127/0003-5548/2012/0170 SN - 0003-5548 VL - 69 IS - 2 SP - 175 EP - 187 PB - Schweizerbart CY - Stuttgart ER - TY - JOUR A1 - Hermanussen, Michael A1 - Lieberman, Leslie Su A1 - Janewa, V. Schoenfeld A1 - Scheffler, Christiane A1 - Ghosh, Arunava A1 - Bogin, Barry A1 - Godina, Elena A1 - Kaczmarek, M. A1 - El-Shabrawi, M. A1 - Salama, E. E. A1 - Rühli, Frank J. A1 - Staub, Kaspar A1 - Woitek, U. A1 - Blaha, Pawel A1 - Aßmann, Christian A1 - van Buuren, Stef A1 - Lehmann, A. A1 - Satake, T. A1 - Thodberg, H. H. A1 - Jopp, E. A1 - Kirchengast, S. A1 - Tutkuviene, J. A1 - McIntyre, M. H. A1 - Wittwer-Backofen, U. A1 - Boldsen, Jesper L. A1 - Martin, D. D. A1 - Meier, J. T1 - Diversity in auxology between theory and practice JF - Journal of biological and clinical anthropology : Anthropologischer Anzeiger ; Mitteilungsorgan der Gesellschaft für Anthropologie N2 - Auxology has developed from mere describing child and adolescent growth into a vivid and interdisciplinary research area encompassing human biologists, physicians, social scientists, economists and biostatisticians. The meeting illustrated the diversity in auxology, with the various social, medical, biological and biostatistical aspects in studies on child growth and development. KW - child growth KW - adolescent growth KW - child development KW - height KW - weight KW - body mass KW - socio-economic environment Y1 - 2012 U6 - https://doi.org/10.1127/0003-5548/2012/0133 SN - 0003-5548 VL - 69 IS - 2 SP - 159 EP - 174 PB - Schweizerbart CY - Stuttgart ER - TY - JOUR A1 - Dunst, Alexander T1 - After trauma time and affect in american culture beyond 9/11 JF - Parallax Y1 - 2012 U6 - https://doi.org/10.1080/13534645.2012.672244 SN - 1353-4645 VL - 18 IS - 2 SP - 56 EP - 71 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Paredes, E. G. A1 - Boo, M. A1 - Amor, M. A1 - Bruguera, J. D. A1 - Döllner, Jürgen Roland Friedrich T1 - Extended hybrid meshing algorithm for multiresolution terrain models JF - International journal of geographical information science N2 - Hybrid terrains are a convenient approach for the representation of digital terrain models, integrating heterogeneous data from different sources. In this article, we present a general, efficient scheme for achieving interactive level-of-detail rendering of hybrid terrain models, without the need for a costly preprocessing or resampling of the original data. The presented method works with hybrid digital terrains combining regular grid data and local high-resolution triangulated irregular networks. Since grid and triangulated irregular network data may belong to different datasets, a straightforward combination of both geometries would lead to meshes with holes and overlapping triangles. Our method generates a single multiresolution model integrating the different parts in a coherent way, by performing an adaptive tessellation of the region between their boundaries. Hence, our solution is one of the few existing approaches for integrating different multiresolution algorithms within the same terrain model, achieving a simple interactive rendering of complex hybrid terrains. KW - 3D modeling KW - 3D visualization KW - geovisualization KW - triangulated irregular networks Y1 - 2012 U6 - https://doi.org/10.1080/13658816.2011.615317 SN - 1365-8816 VL - 26 IS - 5 SP - 771 EP - 793 PB - Routledge, Taylor & Francis Group CY - Abingdon ER -