TY - JOUR A1 - Friedrich, Tobias A1 - Katzmann, Maximilian A1 - Krohmer, Anton T1 - Unbounded Discrepancy of Deterministic Random Walks on Grids JF - SIAM journal on discrete mathematics N2 - Random walks are frequently used in randomized algorithms. We study a derandomized variant of a random walk on graphs called the rotor-router model. In this model, instead of distributing tokens randomly, each vertex serves its neighbors in a fixed deterministic order. For most setups, both processes behave in a remarkably similar way: Starting with the same initial configuration, the number of tokens in the rotor-router model deviates only slightly from the expected number of tokens on the corresponding vertex in the random walk model. The maximal difference over all vertices and all times is called single vertex discrepancy. Cooper and Spencer [Combin. Probab. Comput., 15 (2006), pp. 815-822] showed that on Z(d), the single vertex discrepancy is only a constant c(d). Other authors also determined the precise value of c(d) for d = 1, 2. All of these results, however, assume that initially all tokens are only placed on one partition of the bipartite graph Z(d). We show that this assumption is crucial by proving that, otherwise, the single vertex discrepancy can become arbitrarily large. For all dimensions d >= 1 and arbitrary discrepancies l >= 0, we construct configurations that reach a discrepancy of at least l. KW - deterministic random walk KW - rotor-router model KW - single vertex discrepancy Y1 - 2018 U6 - https://doi.org/10.1137/17M1131088 SN - 0895-4801 SN - 1095-7146 VL - 32 IS - 4 SP - 2441 EP - 2452 PB - Society for Industrial and Applied Mathematics CY - Philadelphia ER - TY - JOUR A1 - Paganelli, Maria Pia A1 - Schumacher, Reinhard T1 - The vigorous and doux soldier BT - David Hume’s military defence of commerce JF - History of European ideas N2 - If war is an inevitable condition of human nature, as David Hume suggests, then what type of societies can best protect us from defeat and conquest? For David Hume, commerce decreases the relative cost of war and promotes technological military advances as well as martial spirit. Commerce therefore makes a country militarily stronger and better equipped to protect itself against attacks than any other kind of society. Hume does not assume commerce would yield a peaceful world nor that commercial societies would be militarily weak, as many contemporary scholars have argued. On the contrary, for him, military might is a beneficial consequence of commerce. KW - Trade and conflict KW - commercial peace KW - David Hume KW - doux commerce KW - cost of war KW - martial spirit Y1 - 2018 U6 - https://doi.org/10.1080/01916599.2018.1509225 SN - 0191-6599 SN - 1873-541X VL - 44 IS - 8 SP - 1141 EP - 1152 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Daviter, Falk T1 - The framing of EU policies JF - Handbook of European Policies Interpretive Approaches to the EU N2 - This chapter discusses how framing analysis can contribute to studies of policy making in the European Union (EU). Framing analysis is understood as an analytical perspective that focuses on how policy problems are constructed and categorised. This analytical perspective allows researchers to reconstruct how shifting problem frames empower competing constituencies and create changing patterns of political participation at the supranational level. Studies that assume a longitudinal perspective on EU policy development show how the framing of EU policy is constitutive of the way in which the jurisdictional boundaries and constitutional mandates of the EU evolve over time. Reviewing the growing body of empirical studies on EU policy framing in the context of the diverse theoretical origins of framing analysis, the chapter argues that framing research which takes seriously the notion that policy-making involves both puzzling and powering allows this analytical perspective to contribute a unique perspective on EU policy making. Y1 - 2018 SN - 978-1-78471-936-4 SN - 978-1-78471-935-7 U6 - https://doi.org/10.1080/13501760701314474 SP - 91 EP - 112 PB - Edward Elgar Publishing CY - Cheltenham ER - TY - JOUR A1 - Afantenos, Stergos A1 - Peldszus, Andreas A1 - Stede, Manfred T1 - Comparing decoding mechanisms for parsing argumentative structures JF - Argument & Computation N2 - Parsing of argumentative structures has become a very active line of research in recent years. Like discourse parsing or any other natural language task that requires prediction of linguistic structures, most approaches choose to learn a local model and then perform global decoding over the local probability distributions, often imposing constraints that are specific to the task at hand. Specifically for argumentation parsing, two decoding approaches have been recently proposed: Minimum Spanning Trees (MST) and Integer Linear Programming (ILP), following similar trends in discourse parsing. In contrast to discourse parsing though, where trees are not always used as underlying annotation schemes, argumentation structures so far have always been represented with trees. Using the ‘argumentative microtext corpus’ [in: Argumentation and Reasoned Action: Proceedings of the 1st European Conference on Argumentation, Lisbon 2015 / Vol. 2, College Publications, London, 2016, pp. 801–815] as underlying data and replicating three different decoding mechanisms, in this paper we propose a novel ILP decoder and an extension to our earlier MST work, and then thoroughly compare the approaches. The result is that our new decoder outperforms related work in important respects, and that in general, ILP and MST yield very similar performance. KW - Argumentation structure KW - argument mining KW - parsing Y1 - 2018 U6 - https://doi.org/10.3233/AAC-180033 SN - 1946-2166 SN - 1946-2174 VL - 9 IS - 3 SP - 177 EP - 192 PB - IOS Press CY - Amsterdam ER - TY - JOUR A1 - Gabriel, Marvin A1 - Toader, Camelia A1 - Faul, Franziska A1 - Rosskopf, Niko A1 - Grundling, Piet-Louis A1 - van Huyssteen, Cornelius W. A1 - Grundling, Althea T. A1 - Zeitz, Jutta T1 - Physical and hydrological properties of peat as proxies for degradation of South African peatlands: Implications for conservation and restoration JF - Mires and peat N2 - The physical and hydrological properties of peat from seven peatlands in northern Maputaland (South Africa) were investigated and related to the degradation processes of peatlands in different hydrogeomorphic settings. The selected peatlands are representative of typical hydrogeomorphic settings and different stages of human modification from natural to severely degraded. Nineteen transects (141 soil corings in total) were examined in order to describe peat properties typical of the distinct hydrogeomorphic settings. We studied degree of decomposition, organic matter content, bulk density, water retention, saturated hydraulic conductivity and hydrophobicity of the peats. From these properties we derived pore size distribution, unsaturated hydraulic conductivity and maximum capillary rise. We found that, after drainage, degradation advances faster in peatlands containing wood peat than in peatlands containing radicell peat. Eucalyptus plantations in catchment areas are especially threatening to peatlands in seeps, interdune depressions and unchannelled valley bottoms. All peatlands and their recharge areas require wise management, especially valley-bottom peatlands with swamp forest vegetation. Blocking drainage ditches is indispensable as a first step towards achieving the restoration of drained peatland areas, and further measures may be necessary to enhance the distribution of water. The sensitive swamp forest ecosystems should be given conservation priority. KW - moorsh forming process KW - swamp forest KW - restoration KW - unsaturated hydraulic conductivity Y1 - 2018 U6 - https://doi.org/10.19189/MaP.2018.OMB.336 SN - 1819-754X VL - 21 PB - International Peat Society CY - Dundee ER - TY - JOUR A1 - Thaler, Verena Sabine A1 - Herbst, Uta A1 - Merz, Michael A. T1 - A real product scandal’s impact on a high-equity brand BT - a new approach to assessing scandal impact to assessing scandal impact JF - Journal of Product & Brand Management N2 - Findings - The results provide (longitudinal) support for the proposed evaluative approach. They reveal new evidence that building brand equity is a means to mitigate negative effects, and indicate that negative spillover effects within a high-equity brand portfolio are unlikely. Finally, this research identifies situations in which developing a new brand might be more beneficial than leveraging an existing brand. Practical implications - This research has significant implications for firms with high-equity brands that might be affected by a scandal. The findings support managers to navigate their brands through a crisis. KW - Crisis management KW - Consumer brand equity KW - Product scandal Y1 - 2018 U6 - https://doi.org/10.1108/JPBM-05-2017-1469 SN - 1061-0421 VL - 27 IS - 4 SP - 427 EP - 439 PB - Emerald Group Publishing Limited CY - Bingley ER - TY - JOUR A1 - Wright, Michelle F. A1 - Wachs, Sebastian A1 - Harper, Bridgette D. T1 - The moderation of empathy in the longitudinal association between witnessing cyberbullying, depression, and anxiety JF - Journal of Psychosocial Research on Cyberspace N2 - While the role of and consequences of being a bystander to face-to-face bullying has received some attention in the literature, to date, little is known about the effects of being a bystander to cyberbullying. It is also unknown how empathy might impact the negative consequences associated with being a bystander of cyberbullying. The present study focused on examining the longitudinal association between bystander of cyberbullying depression, and anxiety, and the moderating role of empathy in the relationship between bystander of cyberbullying and subsequent depression and anxiety. There were 1,090 adolescents (M-age = 12.19; 50% female) from the United States included at Time 1, and they completed questionnaires on empathy, cyberbullying roles (bystander, perpetrator, victim), depression, and anxiety. One year later, at Time 2, 1,067 adolescents (M-age = 13.76; 51% female) completed questionnaires on depression and anxiety. Results revealed a positive association between bystander of cyberbullying and depression and anxiety. Further, empathy moderated the positive relationship between bystander of cyberbullying and depression, but not for anxiety. Implications for intervention and prevention programs are discussed. KW - Bystander KW - cyberbullying KW - empathy KW - depression KW - anxiety KW - longitudinal Y1 - 2018 U6 - https://doi.org/10.5817/CP2018-4-6 SN - 1802-7962 VL - 12 IS - 4 PB - Masrykova Univ. CY - Brno ER - TY - JOUR A1 - Meixner, Johannes M. A1 - Warner, Greta J. A1 - Lensing, Johanna Nele A1 - Schiefele, Ulrich A1 - Elsner, Birgit T1 - The relation between executive functions and reading comprehension in primary-school students BT - a cross-lagged-panel analysis JF - Early Childhood Research Quarterly N2 - Higher-order cognitive skills are necessary prerequisites for reading and understanding words, sentences and texts. In particular, research on executive functions in the cognitive domain has shown that good executive functioning in children is positively related to reading comprehension skills and that deficits in executive functioning are related to difficulties with reading comprehension. However, developmental research on literacy and self-regulation in the early school years suggests that the relation between higher-order cognitive skills and reading might not be unidirectional, but mutually interdependent in nature. Therefore, the present longitudinal study explored the bidirectional relations between executive functions and reading comprehension during primary school across a 1-year period. At two time points (T1, T2), we assessed reading comprehension at the word, sentence, and text levels as well as three components of executive functioning, that is, updating, inhibition, and attention shifting. The sample consisted of three sequential cohorts of German primary school students (N = 1657) starting in first, second, and third grade respectively (aged 6-11 years at T1). Using a latent cross-lagged-panel design, we found bidirectional longitudinal relations between executive functions and reading comprehension for second and third graders. However, for first graders, only the path from executive functioning at T1 to reading comprehension at T2 attained significance. Succeeding analyses revealed updating as the crucial component of the effect from executive functioning on later reading comprehension, whereas text reading comprehension was most predictive of later executive functioning. The potential processes underlying the observed bidirectional relations are discussed with respect to developmental changes in reading comprehension across the primary years. KW - Reading Comprehension KW - Executive Functions KW - Longitudinal Study KW - Latent Variable Analysis KW - Cross-Lagged-Panel Design KW - Bidirectional Relations Y1 - 2018 U6 - https://doi.org/10.1016/j.ecresq.2018.04.010 SN - 0885-2006 SN - 1873-7706 VL - 46 SP - 62 EP - 74 PB - Elsevier CY - New York ER - TY - JOUR A1 - Bacskai-Atkari, Julia T1 - Marking Finiteness and Low Peripheries JF - Boundaries Crossed, at the Interfaces of Morphosyntax, Phonology, Pragmatics and Semantics N2 - The article takes up on the observations made byKenesei (1994) regarding the position of the Hungarian interrogative marker -e in the clause and its distribution across clause types. Specifically, there are three crucial points: (i) the marker -e is related to the CP-domain, where clause typing is encoded; (ii) -e is obligatory in embedded clauses and optional in main clauses; (iii) -e is licensed in finite clauses only. I argue that certain clause-typing properties are reflected in the Hungarian clause in a lower functional domain, FP. In particular, finiteness and the interrogative nature of the clause are encoded here, as also indicated by focussing in non-interrogative clauses and by constituent questions, respectively. The marker -e is base-generated in the F head, as opposed to a designated FocP or TP/IP, allowing it to fulfil its clause-typing functions. Base-generation is crucial (as opposed to lowering from C) since it is able to capture the relatedness between -e and finiteness: -e is specified as [fin] and while the FP may be generated to host focussed constituents (including wh-elements) in non-finite clauses, a lexically [fin] head cannot be inserted. KW - Clause typing KW - Finiteness KW - Focus KW - Functional left peripheries KW - Interrogatives KW - Polar questions Y1 - 2018 SN - 978-3-319-90710-9 SN - 978-3-319-90709-3 U6 - https://doi.org/10.1007/978-3-319-90710-9_12 SN - 0924-4670 VL - 94 SP - 183 EP - 198 PB - Springer CY - Cham ER - TY - JOUR A1 - Angerer, Marie-Luise T1 - Intensive bondage JF - Affect in relation: families, places, technologies Y1 - 2018 SN - 978-1-315-16386-4 SN - 978-1-138-05905-4 SP - 241 EP - 258 PB - Routledge CY - Abingdon ER - TY - JOUR A1 - Barbosa, Luis Romero A1 - Almeida, Cristiano das Neves A1 - Rabelo Coelho, Victor Hugo A1 - Freitas, Emerson da Silva A1 - Galvao, Carlos de Oliveira A1 - de Araujo, Jose Carlos T1 - Sub-hourly rainfall patterns by hyetograph type under distinct climate conditions in Northeast of Brazil BT - a comparative inference of their key properties BT - uma inferência comparativa das suas principais propriedades JF - RBRH Revista Brasileira de Recursos Hídricos Brazilian Journal of Water Resources N2 - The lack of process-based classification procedures may lead to unrealistic hyetograph design due to complex oscillation of rainfall depths when assimilated at high temporal resolutions. Four consecutive years of sub-hourly rainfall data were assimilated in three study areas (Guaraira, GEB, Sao Joao do Cariri, CEB, and Aiuaba, AEB) under distinct climates (very hot semi-arid and tropical wet). This study aimed to define rainfall events (for Minimum Inter-event Time, MIT, and Minimum Rainfall Depth, MRD, equal to 30 min and 1.016 mm, respectively), classify their hyetograph types (rectangular, R, unimodal with left-skewed, UL, right-skewed, UR, and centred peaks, UC, bimodal, B, and shapeless, SL), and compare their key rainfall properties (frequency, duration, depth, rate and peak). A rain pulse aggregation process allowed for reshaping SL-events for six different time spans varying from 2 to 30 min. The results revealed that the coastal area held predominantly R-events (64% events and 49% rainfall depth), in western semi-arid prevailed UL-events (57% events and 63% rainfall depth), whereas in eastern semi-arid mostly were R-events (61% events and 30% rainfall depth) similar to coastal area. It is concluded that each cloud formation type had important effects on hyetograph properties, differentiating them even within the same climate. N2 - A falta de procedimentos de classificação baseados em processos pode levar a uma projeção irreal de hietogramas devido à complexa oscilação das lâminas precipitadas quando assimiladas em altas resoluções temporais. Quatro anos consecutivos de dados pluviográficos sub-horários foram assimilados em três áreas de estudo (Guaraíra, GEB, São João do Cariri, CEB, e Aiuaba, AEB) sob climas distintos (semiárido muito quente e tropical úmido). O objetivo deste estudo foi definir os eventos chuvosos (para Tempo Mínimo entre Eventos, MIT, e Altura Mínima de Precipitação, MRD, iguais a 30 min e 1.016 mm, respectivamente), classificar seus tipos de hietograma (retangular, R, unimodal com pico oblíquo à esquerda, UL, oblíquo à direita, UR, e centrado, UC, bimodal, B, e disforme, SL), e comparar suas principais propriedades de precipitação (frequência, duração, altura, taxa e pico). Um processo de agregação de pulsos de precipitação permitiu remodelar os eventos SL para seis períodos de tempo variando de 2 a 30 min. Os resultados revelaram que a área costeira possuía predominantemente eventos R (64% de eventos e 49% de lâmina precipitada), no semiárido ocidental prevaleceram os eventos UL (57% de eventos e 63% de lâmina precipitada), enquanto no semiárido oriental a maioria foram os eventos R (61% de eventos e 30% de lâmina precipitada) semelhante à área costeira. Conclui-se que cada tipo de formação de nuvens teve efeitos importantes sobre as propriedades dos hietogramas, diferenciando-os até dentro do mesmo clima. T2 - Padrões sub-horários da precipitação por tipo de hietograma em condições climáticas distintas no Nordeste do Brasil KW - Rainfall event KW - MIT KW - MRD KW - Hyetograph classification KW - Northeast of Brazil Y1 - 2018 U6 - https://doi.org/10.1590/2318-0331.231820180076 SN - 1414-381X SN - 2318-0331 VL - 23 PB - Associação Brasileira de Recursos Hídricos CY - Porto Alegre ER - TY - JOUR A1 - Keller, Matthias A1 - Pinchover, Yehuda A1 - Pogorzelski, Felix T1 - An improved discrete hardy inequality JF - The American mathematical monthly : an official publication of the Mathematical Association of America N2 - In this note, we prove an improvement of the classical discrete Hardy inequality. Our improved Hardy-type inequality holds with a weight w which is strictly greater than the classical Hardy weight w(H)(n) : 1/(2n)(2), where N. KW - Primary 26D15 Y1 - 2018 U6 - https://doi.org/10.1080/00029890.2018.1420995 SN - 0002-9890 SN - 1930-0972 VL - 125 IS - 4 SP - 347 EP - 350 PB - Taylor & Francis Group CY - Philadelphia ER - TY - JOUR A1 - Gläßer, Jana A1 - Lauterbach, Wolfgang A1 - Berger, Fred T1 - Predicting the Timing of Social Transitions from Personal, Social and Socio-Economic Resources of German Adolescents JF - Comparative Population Studies N2 - Social transitions are characterized by an increased heterogeneity in Western societies. Following the life course perspective, individual agency becomes central in shaping one’s life course. This article examines social transitions of adolescents using individual resource theory to explain differences of the timing of five transitions in partnership and family formation: the first sexual experience, the first intimate relationship, the first cohabitation, the first marriage, and the birth of the first child. Since little is so far known about how individual characteristics interact and influence the social transition to adulthood, we focus on the varying impacts of personal, social and socio-economic resources across the social life course. We use longitudinal data from the German LifE-Study, which focuses on the birth cohort of individuals born between 1965 and 1967. Using event history analysis, we find that the timing of the first sexual experience and first partnership transitions are mainly influenced by personal and social ressources, whereas socio-economic resources offer better explanations for the timing of entering marriage and parenthood. Most striking are the different explanatory models for women and men. KW - Social transitions KW - Partnership and family formation KW - Resources KW - Life course KW - Youth Y1 - 2018 U6 - https://doi.org/10.12765/CPoS-2018-11en SN - 1869-8980 SN - 1869-8999 VL - 43 SP - 157 EP - 186 PB - Bundesinstitut Bevölkerungsforschung CY - Wiesbaden ER - TY - JOUR A1 - Machatschek, Rainhard Gabriel A1 - Schulz, Burkhard A1 - Lendlein, Andreas T1 - The influence of pH on the molecular degradation mechanism of PLGA JF - MRS Advances N2 - Poly[(rac-lactide)-co-glycolide] (PLGA) is used in medicine to provide mechanical support for healing tissue or as matrix for controlled drug release. The properties of this copolymer depend on the evolution of the molecular weight of the material during degradation. which is determined by the kinetics of the cleavage of hydrolysable bonds. The generally accepted description of the degradation of PLGA is a random fragmentation that is autocatalyzed by the accumulation of acidic fragments inside the bulk material. Since mechanistic studies with lactide oligomers have concluded a chain-end scission mechanism and monolayer degradation experiments with polylactide found no accelerated degradation at lower pH, we hypothesize that the impact of acidic fragments on the molecular degradation kinetics of PLGA is overestimated By means of the Langmuir monolayer degradation technique. the molecular degradation kinetics of PLGA at different pH could be determined. Protons did not catalyze the degradation of PLGA. The molecular mechanism at neutral pH and low pH is a combination of random and chainend-cut events, while the degradation under strongly alkaline conditions is determined by rapid chainend cuts. We suggest that the degradation of bulk PLGA is not catalyzed by the acidic degradation products. Instead. increased concentration of small fragments leads to accelerated mass loss via fast chain-end cut events. In the future, we aim to substantiate the proposed molecular degradation mechanism of PLGA with interfacial rheology. Y1 - 2018 U6 - https://doi.org/10.1557/adv.2018.602 SN - 2059-8521 VL - 3 IS - 63 SP - 3883 EP - 3889 PB - Cambridge Univ. Press CY - New York ER - TY - JOUR A1 - Wischke, Christian A1 - Baehr, Elen A1 - Racheva, Miroslava A1 - Heuchel, Matthias A1 - Weigel, Thomas A1 - Lendlein, Andreas T1 - Surface immobilization strategies for tyrosinase as biocatalyst applicable to polymer network synthesis JF - MRS Advances N2 - Enzymes have recently attracted increasing attention in material research based on their capacity to catalyze the conversion of polymer-bound moieties for synthesizing polymer networks, particularly bulk hydrogels. hi this study. the surface immobilization of a relevant enzyme. mushroom tyrosinase, should be explored using glass as model surface. In a first step. the glass support was functionalized with silanes to introduce either amine or carboxyl groups, as confirmed e.g. by X-ray photoelectron spectroscopy. By applying glutaraldehyde and EDC/NHS chemistry, respectively, surfaces have been activated for subsequent successful coupling of tyrosinase. Via protein hydrolysis and amino acid characterization by HPLC, the quantity of bound tyrosinase was shown to correspond to a full surface coverage. Based on the visualized enzymatic conversion of a test substrate at the glass support. the functionalized surfaces may be explored for surface-associated material synthesis in the future. Y1 - 2018 U6 - https://doi.org/10.1557/adv.2018.630 SN - 2059-8521 VL - 3 IS - 63 SP - 3875 EP - 3881 PB - Cambridge Univ. Press CY - New York ER - TY - JOUR A1 - Farhan, Muhammad A1 - Rudolph, Tobias A1 - Kratz, Karl A1 - Lendlein, Andreas T1 - Torsional Fiber Actuators from Shape-memory Polymer JF - MRS Advances N2 - Humanoid robots, prosthetic limbs and exoskeletons require soft actuators to perform their primary function, which is controlled movement. In this wont we explored whether crosslinked poly[ethylene-co-(vinyl acetate)] (cPEVA) fibers, with different vinyl acetate (VA) content can serve as torsional fiber actuators. exhibiting temperature controlled reversible rotational changes. Broad melting transitions ranging from 50 to 90 degrees C for cPEVA18-165 or from 40 to 80 degrees C for cPEVA28-165 fibers in combination with complete crystallization at temperatures around 10 degrees C make them suitable actuating materials with adjustable actuation temperature ranges between 10 and 70 degrees C during repetitive cooling and heating. The obtained fibers exhibited a circular cross section with diameters around 0.4 +/- 0.1 mm, while a length of 4 cm was employed for the investigation of reversible rotational actuation after programming by twist insertion using 30 complete rotations at a temperature above melting transition. Repetitive heating and cooling between 10 to 60 degrees C or 70 degrees C of one-end-tethered programmed fibers revealed reversible rotations and torsional force. During cooling 3 +/- 1 complete rotations (Delta theta(r) = + 1080 +/- 360 degrees) in twisting direction were observed, while 4 +/- 1 turns in the opposite direction (Delta theta(r) = - 1440 +/- 1360 degrees) were found during heating. Such torsional fiber actuators, which are capable of approximately one rotation per cm fiber length, can serve as miniaturized rotary motors to provide rotational actuation in futuristic humanoid robots. Y1 - 2018 U6 - https://doi.org/10.1557/adv.2018.621 SN - 2059-8521 VL - 3 IS - 63 SP - 3861 EP - 3868 PB - Cambridge Univ. Press CY - New York ER - TY - JOUR A1 - Yan, Wan A1 - Fang, Liang A1 - Nöchel, Ulrich A1 - Gould, Oliver E. C. A1 - Behl, Marc A1 - Kratz, Karl A1 - Lendlein, Andreas T1 - Investigating the roles of crystallizable and glassy switching segments within multiblock copolymer shape-memory materials JF - MRS Advances N2 - The variation of the molecular architecture of multiblock copolymers has enabled the introduction of functional behaviour and the control of key mechanical properties. In the current study, we explore the synergistic relationship of two structural components in a shape-memory material formed of a multiblock copolymer with crystallizable poly(epsilon-caprolactone) and crystallizable polyfoligo(3S-iso-butylmorpholine-2,5-dione) segments (PCL-PIBMD). The thermal and structural properties of PCL-PIBMD films were compared with PCI.-PU and PMMD-PU investigated by means of DSC, SAXS and WARS measurements. The shape-memory properties were quantified by cyclic, thermomechanical tensile tests, where deformation strains up to 900% were applied for programming PCL-PIBMD films at 50 degrees C. Toluene vapor treatment experiments demonstrated that the temporary shape was fixed mainly by glassy PIBMD domains at strains lower than 600% with the PCL contribution to fixation increasing to 42 +/- 2% at programming strains of 900% This study into the shape-memory mechanism of PCL-PIBMD provides insight into the structure function relation in multiblock copolymers with both crystallizable and glassy switching segments. Y1 - 2018 U6 - https://doi.org/10.1557/adv.2018.590 SN - 2059-8521 VL - 3 IS - 63 SP - 3741 EP - 3749 PB - Cambridge Univ. Press CY - New York ER - TY - JOUR A1 - Rungrottheera, Wannarut A1 - Lyu, Xiaojing A1 - Schulze, Bert-Wolfgang T1 - Parameter-dependent edge calculus and corner parametrices JF - Journal of nonlinear and convex analysis : an international journal N2 - Let B be a compact manifold with smooth edge of dimension > 0. We study the interplay between parameter-dependent edge algebra algebra on B and operator families belonging to the corner calculus, and we characterize parametrices in the corner case. KW - Edge calculus KW - corner parametrices Y1 - 2018 SN - 1345-4773 SN - 1880-5221 VL - 19 IS - 12 SP - 2021 EP - 2051 PB - Yokohama Publishers CY - Yokohama ER - TY - JOUR A1 - Ambassa, Pacome L. A1 - Kayem, Anne Voluntas dei Massah A1 - Wolthusen, Stephen D. A1 - Meinel, Christoph T1 - Inferring private user behaviour based on information leakage JF - Smart Micro-Grid Systems Security and Privacy N2 - In rural/remote areas, resource constrained smart micro-grid (RCSMG) architectures can provide a cost-effective power supply alternative in cases when connectivity to the national power grid is impeded by factors such as load shedding. RCSMG architectures can be designed to handle communications over a distributed lossy network in order to minimise operation costs. However, due to the unreliable nature of lossy networks communication data can be distorted by noise additions that alter the veracity of the data. In this chapter, we consider cases in which an adversary who is internal to the RCSMG, deliberately distorts communicated data to gain an unfair advantage over the RCSMG’s users. The adversary’s goal is to mask malicious data manipulations as distortions due to additive noise due to communication channel unreliability. Distinguishing malicious data distortions from benign distortions is important in ensuring trustworthiness of the RCSMG. Perturbation data anonymisation algorithms can be used to alter transmitted data to ensure that adversarial manipulation of the data reveals no information that the adversary can take advantage of. However, because existing data perturbation anonymisation algorithms operate by using additive noise to anonymise data, using these algorithms in the RCSMG context is challenging. This is due to the fact that distinguishing benign noise additions from malicious noise additions is a difficult problem. In this chapter, we present a brief survey of cases of privacy violations due to inferences drawn from observed power consumption patterns in RCSMGs centred on inference, and propose a method of mitigating these risks. The lesson here is that while RCSMGs give users more control over power management and distribution, good anonymisation is essential to protecting personal information on RCSMGs. KW - Approximation algorithms KW - Electrical products KW - Home appliances KW - Load modeling KW - Monitoring KW - Power demand KW - Wireless sensor networks KW - Distributed snapshot algorithm KW - Micro-grid networks KW - Power consumption characterization KW - Sensor networks Y1 - 2018 SN - 978-3-319-91427-5 SN - 978-3-319-91426-8 U6 - https://doi.org/10.1007/978-3-319-91427-5_7 VL - 71 SP - 145 EP - 159 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Marufu, Anesu M. C. A1 - Kayem, Anne Voluntas dei Massah A1 - Wolthusen, Stephen D. T1 - The design and classification of cheating attacks on power marketing schemes in resource constrained smart micro-grids JF - Smart Micro-Grid Systems Security and Privacy N2 - In this chapter, we provide a framework to specify how cheating attacks can be conducted successfully on power marketing schemes in resource constrained smart micro-grids. This is an important problem because such cheating attacks can destabilise and in the worst case result in a breakdown of the micro-grid. We consider three aspects, in relation to modelling cheating attacks on power auctioning schemes. First, we aim to specify exactly how in spite of the resource constrained character of the micro-grid, cheating can be conducted successfully. Second, we consider how mitigations can be modelled to prevent cheating, and third, we discuss methods of maintaining grid stability and reliability even in the presence of cheating attacks. We use an Automated-Cheating-Attack (ACA) conception to build a taxonomy of cheating attacks based on the idea of adversarial acquisition of surplus energy. Adversarial acquisitions of surplus energy allow malicious users to pay less for access to more power than the quota allowed for the price paid. The impact on honest users, is the lack of an adequate supply of energy to meet power demand requests. We conclude with a discussion of the performance overhead of provoking, detecting, and mitigating such attacks efficiently. KW - Smart micro-grids KW - Cheating attacks KW - Power auctioning Y1 - 2018 SN - 978-3-319-91427-5 SN - 978-3-319-91426-8 U6 - https://doi.org/10.1007/978-3-319-91427-5_6 VL - 71 SP - 103 EP - 144 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Kayem, Anne Voluntas dei Massah A1 - Meinel, Christoph A1 - Wolthusen, Stephen D. T1 - A resilient smart micro-grid architecture for resource constrained environments JF - Smart Micro-Grid Systems Security and Privacy N2 - Resource constrained smart micro-grid architectures describe a class of smart micro-grid architectures that handle communications operations over a lossy network and depend on a distributed collection of power generation and storage units. Disadvantaged communities with no or intermittent access to national power networks can benefit from such a micro-grid model by using low cost communication devices to coordinate the power generation, consumption, and storage. Furthermore, this solution is both cost-effective and environmentally-friendly. One model for such micro-grids, is for users to agree to coordinate a power sharing scheme in which individual generator owners sell excess unused power to users wanting access to power. Since the micro-grid relies on distributed renewable energy generation sources which are variable and only partly predictable, coordinating micro-grid operations with distributed algorithms is necessity for grid stability. Grid stability is crucial in retaining user trust in the dependability of the micro-grid, and user participation in the power sharing scheme, because user withdrawals can cause the grid to breakdown which is undesirable. In this chapter, we present a distributed architecture for fair power distribution and billing on microgrids. The architecture is designed to operate efficiently over a lossy communication network, which is an advantage for disadvantaged communities. We build on the architecture to discuss grid coordination notably how tasks such as metering, power resource allocation, forecasting, and scheduling can be handled. All four tasks are managed by a feedback control loop that monitors the performance and behaviour of the micro-grid, and based on historical data makes decisions to ensure the smooth operation of the grid. Finally, since lossy networks are undependable, differentiating system failures from adversarial manipulations is an important consideration for grid stability. We therefore provide a characterisation of potential adversarial models and discuss possible mitigation measures. KW - Resource constrained smart micro-grids KW - Architectures KW - Disadvantaged communities KW - Energy KW - Grid stability KW - Forecasting KW - Feedback control loop Y1 - 2018 SN - 978-3-319-91427-5 SN - 978-3-319-91426-8 U6 - https://doi.org/10.1007/978-3-319-91427-5_5 VL - 71 SP - 71 EP - 101 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Kayem, Anne Voluntas dei Massah A1 - Wolthusen, Stephen D. A1 - Meinel, Christoph T1 - Power Systems BT - a matter of security and privacy JF - Smart Micro-Grid Systems Security and Privacy N2 - Studies indicate that reliable access to power is an important enabler for economic growth. To this end, modern energy management systems have seen a shift from reliance on time-consuming manual procedures, to highly automated management, with current energy provisioning systems being run as cyber-physical systems. Operating energy grids as a cyber-physical system offers the advantage of increased reliability and dependability, but also raises issues of security and privacy. In this chapter, we provide an overview of the contents of this book showing the interrelation between the topics of the chapters in terms of smart energy provisioning. We begin by discussing the concept of smart-grids in general, proceeding to narrow our focus to smart micro-grids in particular. Lossy networks also provide an interesting framework for enabling the implementation of smart micro-grids in remote/rural areas, where deploying standard smart grids is economically and structurally infeasible. To this end, we consider an architectural design for a smart micro-grid suited to low-processing capable devices. We model malicious behaviour, and propose mitigation measures based properties to distinguish normal from malicious behaviour. KW - Lossy networks KW - Low-processing capable devices KW - Smart micro-grids KW - Security KW - Privacy KW - Energy Y1 - 2018 SN - 978-3-319-91427-5 SN - 978-3-319-91426-8 U6 - https://doi.org/10.1007/978-3-319-91427-5_1 VL - 71 SP - 1 EP - 8 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Mücke, Nicole A1 - Blanchard, Gilles T1 - Parallelizing spectrally regularized kernel algorithms JF - Journal of machine learning research N2 - We consider a distributed learning approach in supervised learning for a large class of spectral regularization methods in an reproducing kernel Hilbert space (RKHS) framework. The data set of size n is partitioned into m = O (n(alpha)), alpha < 1/2, disjoint subsamples. On each subsample, some spectral regularization method (belonging to a large class, including in particular Kernel Ridge Regression, L-2-boosting and spectral cut-off) is applied. The regression function f is then estimated via simple averaging, leading to a substantial reduction in computation time. We show that minimax optimal rates of convergence are preserved if m grows sufficiently slowly (corresponding to an upper bound for alpha) as n -> infinity, depending on the smoothness assumptions on f and the intrinsic dimensionality. In spirit, the analysis relies on a classical bias/stochastic error analysis. KW - Distributed Learning KW - Spectral Regularization KW - Minimax Optimality Y1 - 2018 SN - 1532-4435 VL - 19 PB - Microtome Publishing CY - Cambridge, Mass. ER - TY - JOUR A1 - Krüger-Genge, Anne A1 - Dietze, Stefanie A1 - Yan, Wan A1 - Liu, Yue A1 - Fang, Liang A1 - Kratz, Karl A1 - Lendlein, Andreas A1 - Jung, Friedrich T1 - Endothelial cell migration, adhesion and proliferation on different polymeric substrates JF - Clinical hemorheology and microcirculation : blood flow and vessels N2 - BACKGROUND: The formation of a functionally-confluent endothelial cell (EC) monolayer affords proliferation of EC, which only happens in case of appropriate migratory activity. AIM OF THE STUDY: The migratory pathway of human umbilical endothelial cells (HUVEC) was investigated on different polymeric substrates. MATERIAL AND METHODS: Surface characterization of the polymers was performed by contact angle measurements and atomic force microscopy under wet conditions. 30,000 HUVEC per well were seeded on polytetrafluoroethylene (PTFE) (theta(adv) = 119 degrees +/- 2 degrees), on low-attachment plate LAP (theta(adv) = 28 degrees +/- 2 degrees) and on polystyrene based tissue culture plates (TCP, theta(adv) = 22 degrees +/- 1 degrees). HUVEC tracks (trajectories) were recorded by time lapse microscopy and the euclidean distance (straight line between starting and end point), the total distance and the velocities of HUVEC not leaving the vision field were determined. RESULTS: On PTFE, 42 HUVEC were in the vision field directly after seeding. The mean length of single migration steps (SML) was 6.1 +/- 5.2 mu m, the mean velocity (MV) 0.40 +/- 0.3 mu m.min(-1) and the complete length of the trajectory (LT) was 710 +/- 440 mu m. On TCP 82 HUVEC were in the vision field subsequent to seeding. The LT was 840 +/- 550 mu m, the SML 6.1 +/- 5.2 mu m and the MV 0.44 +/- 0.3 mu m.min(-1). The trajectories on LAP differed significantly in respect to SML (2.4 +/- 3.9 mu m, p <0.05), the MV (0.16 +/- 0.3 mu m.min(-1), p <0.05) and the LT (410 +/- 300 mu m, p <0.05), compared to PTFE and TCP. Solely on TCP a nearly confluent EC monolayer developed after three days. While on TCP diffuse signals of vinculin were found over the whole basal cell surface organizing the binding of the cells by focal adhesions, on PTFE vinculin was merely arranged at the cell rims, and on the hydrophilic material (LAP) no focal adhesions were found. CONCLUSION: The study revealed that the wettability of polymers affected not only the initial adherence but also the migration of EC, which is of importance for the proliferation and ultimately the endothelialization of polymer-based biomaterials. KW - Endothelial cells KW - migration KW - polymer-based biomaterials KW - cytokine release Y1 - 2019 U6 - https://doi.org/10.3233/CH-189317 SN - 1386-0291 SN - 1875-8622 VL - 70 IS - 4 SP - 511 EP - 529 PB - IOS Press CY - Amsterdam ER - TY - JOUR A1 - Paycha, Sylvie T1 - When the market wins over research and higher education JF - Sustainable Futures for Higher Education : the Making of Knowledge Makers N2 - In this chapter, an overview of systematic eradication of basic science foci in European universities in the last two decades is given. This happens under the slogan of optimisation of the university education to the needs and demands of the society. It is pointed out that reliance on “market demands” brings with it long-term deficiencies in the maintenance of basic and advanced knowledge construction in societies necessary for long-term future technological advances. University policies that claim improvement of higher education towards more immediate efficiency may end up with the opposite effect of affecting its quality and long term expected positive impact on society. Y1 - 2018 SN - 978-3-319-96035-7 SN - 978-3-319-96034-0 U6 - https://doi.org/10.1007/978-3-319-96035-7_2 SN - 2364-6799 VL - 7 SP - 23 EP - 28 PB - Springer CY - Cham ER - TY - JOUR A1 - Krahe, Barbara T1 - The impact of violent media on aggression JF - The Routledge International Handbook of Human Aggression : Current Issues and Perspectives Y1 - 2018 SN - 978-1-315-61877-7 SN - 978-1-138-66818-8 SP - 319 EP - 330 PB - Routledge CY - Abingdon ER - TY - JOUR A1 - Höhne, Chris A1 - Fuhr, Harald A1 - Hickmann, Thomas A1 - Lederer, Markus A1 - Stehle, Fee ED - Nuesiri, Emmanuel O. T1 - REDD plus and the reconfiguration of public authority in the forest sector BT - a comparative case study of Indonesia and Brazil JF - Global Forest Governance and Climate Change N2 - Since the 1980s, central governments have decentralized forestry to local governments in many countries of the Global South. More recently, REDD+ has started to impact forest policy-making in these countries by providing incentives to ensure a national-level approach to reducing emissions from deforestation and forest degradation. Höhne et al. analyze to what extent central governments have rebuilt capacity at the national level, imposed regulations from above, and interfered in forest management by local governments for advancing REDD+. Using the examples of Brazil and Indonesia, the chapter illustrates that while REDD+ has not initiated a large-scale recentralization in the forestry sector, it has supported the reinforcement and pooling of REDD+ related competences at the central government level. Y1 - 2018 SN - 978-3-319-71946-7 SN - 978-3-319-71945-0 U6 - https://doi.org/10.1007/978-3-319-71946-7_8 SP - 203 EP - 241 PB - Palgrave CY - Basingstoke ER - TY - JOUR A1 - Bachoc, Francois A1 - Blanchard, Gilles A1 - Neuvial, Pierre T1 - On the post selection inference constant under restricted isometry properties JF - Electronic journal of statistics N2 - Uniformly valid confidence intervals post model selection in regression can be constructed based on Post-Selection Inference (PoSI) constants. PoSI constants are minimal for orthogonal design matrices, and can be upper bounded in function of the sparsity of the set of models under consideration, for generic design matrices. In order to improve on these generic sparse upper bounds, we consider design matrices satisfying a Restricted Isometry Property (RIP) condition. We provide a new upper bound on the PoSI constant in this setting. This upper bound is an explicit function of the RIP constant of the design matrix, thereby giving an interpolation between the orthogonal setting and the generic sparse setting. We show that this upper bound is asymptotically optimal in many settings by constructing a matching lower bound. KW - Inference post model-selection KW - confidence intervals KW - PoSI constants KW - linear regression KW - high-dimensional inference KW - sparsity KW - restricted isometry property Y1 - 2018 U6 - https://doi.org/10.1214/18-EJS1490 SN - 1935-7524 VL - 12 IS - 2 SP - 3736 EP - 3757 PB - Institute of Mathematical Statistics CY - Cleveland ER - TY - JOUR A1 - Blanchard, Gilles A1 - Carpentier, Alexandra A1 - Gutzeit, Maurilio T1 - Minimax Euclidean separation rates for testing convex hypotheses in R-d JF - Electronic journal of statistics N2 - We consider composite-composite testing problems for the expectation in the Gaussian sequence model where the null hypothesis corresponds to a closed convex subset C of R-d. We adopt a minimax point of view and our primary objective is to describe the smallest Euclidean distance between the null and alternative hypotheses such that there is a test with small total error probability. In particular, we focus on the dependence of this distance on the dimension d and variance 1/n giving rise to the minimax separation rate. In this paper we discuss lower and upper bounds on this rate for different smooth and non-smooth choices for C. KW - Minimax hypothesis testing KW - Gaussian sequence model KW - nonasymptotic minimax separation rate Y1 - 2018 U6 - https://doi.org/10.1214/18-EJS1472 SN - 1935-7524 VL - 12 IS - 2 SP - 3713 EP - 3735 PB - Institute of Mathematical Statistics CY - Cleveland ER - TY - JOUR A1 - Blanchard, Gilles A1 - Hoffmann, Marc A1 - Reiss, Markus T1 - Early stopping for statistical inverse problems via truncated SVD estimation JF - Electronic journal of statistics N2 - We consider truncated SVD (or spectral cut-off, projection) estimators for a prototypical statistical inverse problem in dimension D. Since calculating the singular value decomposition (SVD) only for the largest singular values is much less costly than the full SVD, our aim is to select a data-driven truncation level (m) over cap is an element of {1, . . . , D} only based on the knowledge of the first (m) over cap singular values and vectors. We analyse in detail whether sequential early stopping rules of this type can preserve statistical optimality. Information-constrained lower bounds and matching upper bounds for a residual based stopping rule are provided, which give a clear picture in which situation optimal sequential adaptation is feasible. Finally, a hybrid two-step approach is proposed which allows for classical oracle inequalities while considerably reducing numerical complexity. KW - Linear inverse problems KW - truncated SVD KW - spectral cut-off KW - early stopping KW - discrepancy principle KW - adaptive estimation KW - oracle inequalities Y1 - 2018 U6 - https://doi.org/10.1214/18-EJS1482 SN - 1935-7524 VL - 12 IS - 2 SP - 3204 EP - 3231 PB - Institute of Mathematical Statistics CY - Cleveland ER - TY - JOUR A1 - Wawrzinek, Jennifer T1 - Postcolonial dandies and the death of the flâneur JF - South and North : Contemporary Urban Orientations Y1 - 2018 SN - 978-1-351-04704-3 SN - 978-0-815-39684-0 SP - 161 EP - 179 PB - Routledge CY - London ER - TY - JOUR A1 - Wilke, Max T1 - X-Ray Absorption Spectroscopy Measurements JF - Magmas Under Pressure : Advances in High-Pressure Experiments on Structure and Properties of Melts N2 - An overview is given on the current state of X-ray absorption measurements on silicate melts and glasses. The challenges, limitations, and achievements of analyzing X-ray absorption spectra measured in liquids to determine structural properties of major and minor elements in magmas are described, with particular focus on describing non-Gaussian pair distribution functions in highly disordered glasses and melts, measured at in situ conditions. This includes a discussion on the progress of combining experiments with data from molecular dynamics simulations. For the measurements at conditions of the deep Earth, various experimental approaches and necessities are discussed and two examples are described in more detail. Finally, the achievements and prospects are presented for measuring X-ray absorption spectra indirectly by X-ray Raman scattering. Y1 - 2018 SN - 978-0-12-811274-8 SN - 978-0-12-811301-1 U6 - https://doi.org/10.1016/B978-0-12-811301-1.00006-X SP - 155 EP - 178 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Jungbauer, Johannes A1 - Heitmann, Katharina A1 - Westphal, Andrea A1 - Vock, Miriam T1 - Erwachsene Kinder psychisch erkrankter Eltern T1 - Adult children of parents with mental illnesses BT - Ergebnisse einer explorativen Fragebogenstudie BT - Results from an exploratory survey JF - Zeitschrift für Familienforschung JF - Journal of Family Research N2 - Zielsetzung: In diesem Beitrag werden Ergebnisse der EKipeE-Studie vorgestellt, in der erwachsene Kinder psychisch kranker Eltern befragt wurden. Ziel war es, die von den Befragten wahrgenommenen langfristigen Auswirkungen auf ihre Biographie, ihre Persönlichkeit und ihre Sozialbeziehungen zu beschreiben. Außerdem sollten Zusammenhänge zwischen ausgewählten belastenden Kindheitserfahrungen und Problemen im Erwachsenenalter untersucht werden. Ferner sollten die Unterstützungsbedürfnisse und -wünsche der erwachsenen Kinder erfasst werden. Methode: Im Rahmen einer online-Fragebogenstudie wurden N=561 erwachsene Kinder psychisch kranker Eltern befragt. Die quantitativen Fragebogendaten wurden mit SPSS 23.0 statistisch ausgewertet; die freien Antworten und Kommentare wurden inhaltsanalytisch ausgewertet. Ergebnisse: Die Studienteilnehmer berichteten vielfältige emotionale und soziale Probleme, die sie als Folgen ihrer Kindheitserfahrungen wahrnehmen. Sehr häufig haben sie das Gefühl, in ihrer Identität und ihrem Verhalten negativ geprägt zu sein. Viele äußern deswegen einen Bedarf an professioneller Beratung und Unterstützung. Diskussion: Es handelt sich um die bislang umfangreichste Studie zu den langfristigen Folgen einer Kindheit mit einem psychisch kranken Elternteil im deutschsprachigen Raum. Die Ergebnisse verdeutlichen, dass frühzeitige Hilfe- und Präventionsangebote für betroffene Kinder, Eltern und Familien notwendig sind. Auch die Bereitstellung spezifischer Beratungsangebote für erwachsene Kinder psychisch kranker Eltern wird empfohlen. N2 - Objective: This paper presents the results of the EKipeE Study, which surveyed the adult children of parents with mental illnesses. The objective of the study was to extrapolate the long-term effects that parents’ mental illnesses had on their children’s biographies, personalities, and social relationships. The study also aimed to make connections between specific stressful situations in childhood and problems in later life. Additionally, the study aimed to understand what kind of support the adult children required and wanted. Method: Using an online questionnaire, N=561 adult children of parents with mental illnesses were surveyed. The quantitative survey data was statistically analyzed using SPSS 23.0; the qualitative data from answers and other remarks was evaluated using content analysis. Results: Participants in the study reported a diverse range of emotions and social problems that they perceived as having resulted from their childhood experiences. They often had the feeling that their identity and behavior had been affected negatively. Consequently, many expressed a need for professional counselling and support. Discussion: The study was the most extensive to date within German- speaking countries to survey the long-term effects of a childhood spent with a parent with mental illnesses. The results underline the need for early support and prevention services for affected children, parents, and families. The provision of specific counselling services for adult children of parents with mental illnesses is also recommended. KW - adult children KW - parents with mental illnesses KW - long-term effects KW - development risks KW - support for affected families KW - erwachsene Kinder KW - psychisch kranke Eltern KW - langfristige Auswirkungen KW - Entwicklungsrisiken KW - Hilfebedarf für betroffene Familien Y1 - 2018 U6 - https://doi.org/10.3224/zff.v30i2.05 SN - 1437-2940 SN - 2196-2154 VL - 30 IS - 2 SP - 216 EP - 229 PB - Budrich CY - Leverkusen ER - TY - JOUR A1 - Razzaq, Muhammad Yasar A1 - Behl, Marc A1 - Lendlein, Andreas T1 - Thermally-induced actuation of magnetic nanocomposites based on Oligo(ω-pentadecalactone) and covalently integrated magnetic nanoparticles JF - MRS advances: a journal of the Materials Research Society (MRS) N2 - The incorporation of inorganic particles in a polymer matrix has been established as a method to adjust the mechanical performance of composite materials. We report on the influence of covalent integration of magnetic nanoparticles (MNP) on the actuation behavior and mechanical performance of hybrid nanocomposite (H-NC) based shape-memory polymer actuators (SMPA). The H-NC were synthesized by reacting two types of oligo(ω-pentadecalactone) (OPDL) based precursors with terminal hydroxy groups, a three arm OPDL (3 AOPDL, Mn = 6000 g mol•1−1 ) and an OPDL (Mn =3300 g • mol−1 ) coated magnetite nanoparticle (Ø = 10 ± 2 nm), with a diisocyanate. These H-NC were compared to the homopolymer network regarding the actuation performance, contractual stress (σcontr) as well as thermal and mechanical properties. The melting range of the OPDL crystals (ΔTm,OPDL) was shifted in homo polymer networks from 36 ºC − 76 ºC to 41ºC − 81 °C for H-NC with 9 wt% of MNP content. The actuators were explored by variation of separating temperature (Tsep), which splits the OPDL crystalline domain into actuating and geometry determining segments. Tsep was varied in the melting range of the nanocomposites and the actuation capability and contractual stress (σcontr) of the nanocomposite actuators could be adjusted. The reversible strain (εrev) was decreased from 11 ± 0.3% for homo polymer network to 3.2±0.3% for H-NC9 with 9 wt% of MNP indicating a restraining effect of the MNP on chain mobility. The results show that the performance of H-NCs in terms of thermal and elastic properties can be tailored by MNP content, however for higher reversible actuation, lower MNP contents are preferable. Y1 - 2018 U6 - https://doi.org/10.1557/adv.2018.613 SN - 2059-8521 VL - 3 IS - 63 SP - 3783 EP - 3791 PB - Cambridge University Press CY - New York ER - TY - JOUR A1 - Lukan, Tjaša A1 - Machens, Fabian A1 - Coll, Anna A1 - Baebler, Špela A1 - Messerschmidt, Katrin A1 - Gruden, Kristina T1 - Plant X-tender BT - an extension of the AssemblX system for the assembly and expression of multigene constructs in plants JF - PLOS ONE N2 - Cloning multiple DNA fragments for delivery of several genes of interest into the plant genome is one of the main technological challenges in plant synthetic biology. Despite several modular assembly methods developed in recent years, the plant biotechnology community has not widely adopted them yet, probably due to the lack of appropriate vectors and software tools. Here we present Plant X-tender, an extension of the highly efficient, scar-free and sequence-independent multigene assembly strategy AssemblX, based on overlap-depended cloning methods and rare-cutting restriction enzymes. Plant X-tender consists of a set of plant expression vectors and the protocols for most efficient cloning into the novel vector set needed for plant expression and thus introduces advantages of AssemblX into plant synthetic biology. The novel vector set covers different backbones and selection markers to allow full design flexibility. We have included ccdB counterselection, thereby allowing the transfer of multigene constructs into the novel vector set in a straightforward and highly efficient way. Vectors are available as empty backbones and are fully flexible regarding the orientation of expression cassettes and addition of linkers between them, if required. We optimised the assembly and subcloning protocol by testing different scar-less assembly approaches: the noncommercial SLiCE and TAR methods and the commercial Gibson assembly and NEBuilder HiFi DNA assembly kits. Plant X-tender was applicable even in combination with low efficient homemade chemically competent or electrocompetent Escherichia coli. We have further validated the developed procedure for plant protein expression by cloning two cassettes into the newly developed vectors and subsequently transferred them to Nicotiana benthamiana in a transient expression setup. Thereby we show that multigene constructs can be delivered into plant cells in a streamlined and highly efficient way. Our results will support faster introduction of synthetic biology into plant science. Y1 - 2018 U6 - https://doi.org/10.1371/journal.pone.0190526 SN - 1932-6203 VL - 13 IS - 1 PB - Public Library of Science CY - San Fransisco ER - TY - JOUR A1 - Ryll, Britta A1 - Schmitz, Andreas A1 - de Boor, Johannes A1 - Franz, Alexandra A1 - Whitfield, Pamela S. A1 - Reehuis, Manfred A1 - Hoser, Andreas A1 - Müller, Eckhard A1 - Habicht, Klaus A1 - Fritscht, Katharina T1 - Structure, phase composition, and thermoelectric properties of YbxCo4Sb12 and their dependence on synthesis method JF - ACS applied energy materials N2 - We present a combined microscopic and macroscopic study of YbxCo4Sb12 skutterudites for a range of nominal filling fractions, 0.15 < x < 0.75. The samples were synthesized using two different methods — a melt–quench–annealing route in evacuated quartz ampoules and a non-equilibrium ball-mill route — for which we directly compare the crystal structure and phase composition as well as the thermoelectric properties. Rietveld refinements of high-quality neutron powder diffraction data reveal about a 30–40% smaller Yb occupancy on the crystallographic 2a site than nominally expected for both synthesis routes. We observe a maximum filling fraction of at least 0.439(7) for a sample synthesized by the ball-mill routine, exceeding theoretical predictions of the filling fraction limit of 0.2–0.3. A single secondary phase of CoSb2 is observed in ball-mill-synthesized samples, while two secondary phases, CoSb2 and YbSb2, are detected for samples prepared by the ampoule route. A detrimental influence of the secondary phases on the thermoelectric properties is observed for secondary-phase fractions larger than 8 wt % regardless of the kind of secondary phase. The largest figure of merit of all samples with a ZT ∼ 1.0 at 723 K is observed for the sample with a refined Yb content of x2a = 0.159(3), synthesized by the ampoule route. KW - thermoelectric materials KW - skutterudite KW - melt-quench-anneal KW - ball mill KW - neutron powder diffraction KW - thermoelectric properties KW - figure of merit Y1 - 2017 U6 - https://doi.org/10.1021/acsaem.7b00015 SN - 2574-0962 VL - 1 IS - 1 SP - 113 EP - 122 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Kretschmer, Marlene A1 - Cohen, Judah A1 - Matthias, Vivien A1 - Runge, Jakob A1 - Coumou, Dim T1 - The different stratospheric influence on cold-extremes in Eurasia and North America JF - npj Climate and Atmospheric Science N2 - The stratospheric polar vortex can influence the tropospheric circulation and thereby winter weather in the mid-latitudes. Weak vortex states, often associated with sudden stratospheric warmings (SSW), have been shown to increase the risk of cold-spells especially over Eurasia, but its role for North American winters is less clear. Using cluster analysis, we show that there are two dominant patterns of increased polar cap heights in the lower stratosphere. Both patterns represent a weak polar vortex but they are associated with different wave mechanisms and different regional tropospheric impacts. The first pattern is zonally symmetric and associated with absorbed upward-propagating wave activity, leading to a negative phase of the North Atlantic Oscillation (NAO) and cold-air outbreaks over northern Eurasia. This coupling mechanism is well-documented in the literature and is consistent with the downward migration of the northern annular mode (NAM). The second pattern is zonally asymmetric and linked to downward reflected planetary waves over Canada followed by a negative phase of the Western Pacific Oscillation (WPO) and cold-spells in Central Canada and the Great Lakes region. Causal effect network (CEN) analyses confirm the atmospheric pathways associated with this asymmetric pattern. Moreover, our findings suggest the reflective mechanism to be sensitive to the exact region of upward wave-activity fluxes and to be state-dependent on the strength of the vortex. Identifying the causal pathways that operate on weekly to monthly timescales can pave the way for improved sub-seasonal to seasonal forecasting of cold spells in the mid-latitudes. Y1 - 2018 U6 - https://doi.org/10.1038/s41612-018-0054-4 SN - 2397-3722 VL - 1 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Elsässer, Joshua Philipp A1 - Hickmann, Thomas A1 - Stehle, Fee T1 - The Role of Cities in South Africa’s Energy Gridlock JF - Case Studies in the Environment N2 - South Africa’s energy sector finds itself in a gridlock situation. The sector is controlled by the state-owned utility Eskom holding the monopoly on the generation and transmission of electricity, which is almost exclusively produced from domestically extracted coal. At the same time, the constitutional mandate enables municipalities to distribute and sell electricity generated by Eskom to local consumers, which constitutes a large part of the cities’ municipal income. This is a strong disincentive for city governments to promote reductions in energy consumption and substantially limits the scope for urban action on energy efficiency and renewable energies. In the present case study, we portray the current development in South Africa’s energy policy and trace how deadlocked legal, financial, and institutional barriers block the transition from a coal-based energy system toward a greener and more sustainable energy economy. We furthermore point to the efforts of major South African cities to introduce low-carbon strategies in their jurisdictions and highlight key challenges for the future development of the country’s energy sector. By engaging with this case study, readers will become familiar with a prime example of the wider phenomenon of national political–economic obstacles to the progress in sustainable urban development. Y1 - 2018 U6 - https://doi.org/10.1525/cse.2018.001297 SN - 2473-9510 VL - 2 IS - 1 SP - 1 EP - 7 PB - University of California Press CY - Oakland ER - TY - JOUR A1 - Hänsel, Sylvaine T1 - Material and expression - reflections on sculptures by Richard Serra and Eduardo Chillida JF - Sculpture Journal N2 - When considering artists from the second half of the twentieth century who used steel as material for their sculptures, Eduardo Chillida and Richard Serra are among the first to come to mind. Both artists are prominent in public spaces and both present large-size sculptures which challenge viewers. Both use clear geometrical patterns, and both develop their oeuvre from an intense involvement with the properties and possibilities of the material. However, their sculptures show fundamentally diverging conceptions not only in the manner of their creation, but also in their reception. Chillida and Serra have almost nothing in common; they never made reference to each other, although their sculptures often stand in neighbourly proximity. Nevertheless a comparison or more precisely a synopsis can illustrate a number of problems that rise in dealing with sculpture today. Serra’s works convince mostly when they concentrate on complex formal qualities resulting from constellations of geometrical forms and given spaces. However, sculptures in public space consistently have the difficult task of creating memorial places which ideally speak for themselves. Chillida’s sculptures fulfil this purpose because of their expressive pictorial potential. The material COR-TEN steel provides them with power and emphasis. Y1 - 2018 U6 - https://doi.org/10.3828/sj.2018.27.3.5 SN - 1366-2724 SN - 1756-9923 VL - 27 IS - 3 SP - 321 EP - 331 PB - Liverpool Univ. Press CY - Liverpool ER - TY - JOUR A1 - Lisson, Paula A1 - Ballier, Nicolas T1 - Investigating Lexical Progression through Lexical Diversity Metrics in a Corpus of French L3 JF - Discours : revue de linguistique, psycholinguistique et informatique N2 - This article presents a corpus-based evaluation of 13 lexical diversity metrics as measures of longitudinal progression in written productions of learners of French as third language (L3). Our case study (24 learners, 3 productions per learner in the course of 3 months) deals with a semi-longitudinal corpus, where each of the productions is supposed to be more complex than the previous one. Random forests (Breiman, 2001; Hothorn et al., 2019) are used in order to see whether lexical diversity metric scores capture enough vocabulary diversity progression to predict the production wave. We report that lexical diversity metrics capture lexical progression through the three productions of each student. In particular, two metrics appear to be the most informative for lexical progression: Herdan’s C and Yule’s K. KW - lexical diversity KW - learner corpora KW - L3 French Y1 - 2018 U6 - https://doi.org/10.4000/discours.9950 SN - 1963-1723 IS - 23 PB - Université de Paris-Sorbonne, Maion Recherche CY - Paris ER - TY - JOUR A1 - Sprinz, Detlef F. A1 - Bang, Guri A1 - Brueckner, Lars A1 - Kameyama, Yasuko ED - Luterbacher, Urs ED - Sprinz, Detlef F. T1 - Major Countries JF - Global climate policy: actors, concepts, and enduring challenges Y1 - 2018 SN - 978-0-262-53534-2 SN - 978-0-262-03792-1 SP - 171 EP - 216 PB - MIT Press CY - Cambridge ER - TY - JOUR A1 - Ette, Ottmar T1 - TransArea Tangier BT - the city and the literatures of the world JF - Re-mapping World Literature Writing, Book Markets and Epistemologies between Latin America and the Global South / Escrituras, mercados y epistemologías entre América Latina y el Sur Global Y1 - 2018 SN - 978-3-11-054957-7 SN - 978-3-11-054952-2 U6 - https://doi.org/10.1515/9783110549577-019 SN - 2513-0757 SP - 283 EP - 321 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Stober, Sebastian A1 - Sternin, Avital T1 - Decoding music perception and imagination using deep-learning techniques JF - Signal processing and machine learning for brain-machine interfaces N2 - Deep learning is a sub-field of machine learning that has recently gained substantial popularity in various domains such as computer vision, automatic speech recognition, natural language processing, and bioinformatics. Deep-learning techniques are able to learn complex feature representations from raw signals and thus also have potential to improve signal processing in the context of brain-computer interfaces (BCIs). However, they typically require large amounts of data for training - much more than what can often be provided with reasonable effort when working with brain activity recordings of any kind. In order to still leverage the power of deep-learning techniques with limited available data, special care needs to be taken when designing the BCI task, defining the structure of the deep model, and choosing the training method. This chapter presents example approaches for the specific scenario of music-based brain-computer interaction through electroencephalography - in the hope that these will prove to be valuable in different settings as well. We explain important decisions for the design of the BCI task and their impact on the models and training techniques that can be used. Furthermore, we present and compare various pre-training techniques that aim to improve the signal-to-noise ratio. Finally, we discuss approaches to interpret the trained models. Y1 - 2018 SN - 978-1-78561-399-9 SN - 978-1-78561-398-2 U6 - https://doi.org/10.1049/PBCE114E VL - 114 SP - 271 EP - 299 PB - Institution of Engineering and Technology CY - London ER - TY - JOUR A1 - Merz, Bruno A1 - Apel, Heiko A1 - Dung Nguyen, Viet-Dung A1 - Falter, Daniela A1 - Guse, Björn A1 - Hundecha, Yeshewatesfa A1 - Kreibich, Heidi A1 - Schröter, Kai A1 - Vorogushyn, Sergiy T1 - From precipitation to damage BT - a coupled model chain for spatially coherent, large-scale flood risk assessment JF - Global flood hazard : applications in modeling, mapping and forecasting N2 - Flood risk assessments for large river basins often involve piecing together smaller-scale assessments leading to erroneous risk statements. We describe a coupled model chain for quantifying flood risk at the scale of 100,000 km(2). It consists of a catchment model, a 1D-2D river network model, and a loss model. We introduce the model chain and present two applications. The first application for the Elbe River basin with an area of 66,000 km(2) demonstrates that it is feasible to simulate the complete risk chain for large river basins in a continuous simulation mode with high temporal and spatial resolution. In the second application, RFM is coupled to a multisite weather generator and applied to the Mulde catchment with an area of 6,000 km(2). This approach is able to provide a very long time series of spatially heterogeneous patterns of precipitation, discharge, inundation, and damage. These patterns respect the spatial correlation of the different processes and are suitable to derive large-scale risk estimates. We discuss how the RFM approach can be transferred to the continental scale. Y1 - 2018 SN - 978-1-119-21788-6 SN - 978-1-119-21786-2 U6 - https://doi.org/10.1002/9781119217886.ch10 SN - 0065-8448 VL - 233 SP - 169 EP - 183 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Scheller, Henrik T1 - German Federalism: On the Way to a "Cooperative Centralism"? JF - Identities, trust, and cohesion in federal systems: public perspectives N2 - Germany has a long tradition of federalism extending far back in history (Ziblatt 2004; Broschek 2011). This tradition has always been characterized by a discrepancy between the attitudes of the public to its federalism and the reform ideas of the (political) elites. While the public has a strong desire for an equality of living conditions, solidarity, social cohesion, and cooperation between the orders of government, academic discourse is shaped by calls for wide-ranging federalism reforms, which are oriented toward the American model of "dual federalism." Against this background, this chapter contrasts public attitudes on key aspects of the federal system with long-lasting academic recommendations for reform. Light will be shed on the general perception of the federal system as a whole, the division of powers, and in particular the issue of joint decision-making (Politikverflechtung) between the orders of government-all issues that have been repeatedly interrogated in various surveys. A further aspect of these polls is the question of the extent to which solidarity or competition shall be realized between the federal and Land governments-a question that is highly controversial in politics and academia (especially in the fiscal equalization debate), though public perceptions are quite different. Y1 - 2018 SN - 978-1-55339-535-5 SN - 978-1-55339-536-2 SP - 255 EP - 279 PB - McGill-Queens University Press CY - Montreal ER - TY - JOUR A1 - Fyndanis, Valantis A1 - Arcara, Giorgio A1 - Capasso, Rita A1 - Christidou, Paraskevi A1 - De Pellegrin, Serena A1 - Gandolfi, Marialuisa A1 - Messinis, Lambros A1 - Panagea, Evgenia A1 - Papathanasopoulos, Panagiotis A1 - Smania, Nicola A1 - Semenza, Carlo A1 - Miceli, Gabriele T1 - Time reference in nonfluent and fluent aphasia BT - a cross-linguistic test of the PAst Discourse Linking Hypothesis JF - Clinical linguistics & phonetics N2 - Recent studies by Bastiaanse and colleagues found that time reference is selectively impaired in people with nonfluent agrammatic aphasia, with reference to the past being more difficult to process than reference to the present or to the future. To account for this dissociation, they formulated the PAst DIscourse LInking Hypothesis (PADILIH), which posits that past reference is more demanding than present/future reference because it involves discourse linking. There is some evidence that this hypothesis can be applied to people with fluent aphasia as well. However, the existing evidence for the PADILIH is contradictory, and most of it has been provided by employing a test that predominantly taps retrieval processes, leaving largely unexplored the underlying ability to encode time reference-related prephonological features. Within a cross-linguistic approach, this study tests the PADILIH by means of a sentence completion task that 'equally' taps encoding and retrieval abilities. This study also investigates if the PADILIH’s scope can be extended to fluent aphasia. Greek- and Italian-speaking individuals with aphasia participated in the study. The Greek group consisted of both individuals with nonfluent agrammatic aphasia and individuals with fluent aphasia, who also presented signs of agrammatism. The Italian group consisted of individuals with agrammatic nonfluent aphasia only. The two Greek subgroups performed similarly. Neither language group of participants with aphasia exhibited a pattern of performance consistent with the predictions of the PADILIH. However, a double dissociation observed within the Greek group suggests a hypothesis that may reconcile the present results with the PADILIH. KW - Time reference KW - past reference KW - future reference KW - encoding KW - retrieval Y1 - 2018 U6 - https://doi.org/10.1080/02699206.2018.1445291 SN - 0269-9206 SN - 1464-5076 VL - 32 IS - 9 SP - 823 EP - 843 PB - Taylor & Francis Group CY - Philadelphia ER - TY - JOUR A1 - Goswami, Bedartha A1 - Boers, Niklas A1 - Rheinwalt, Aljoscha A1 - Marwan, Norbert A1 - Heitzig, Jobst A1 - Breitenbach, Sebastian Franz Martin A1 - Kurths, Jürgen T1 - Abrupt transitions in time series with uncertainties JF - Nature Communications N2 - Identifying abrupt transitions is a key question in various disciplines. Existing transition detection methods, however, do not rigorously account for time series uncertainties, often neglecting them altogether or assuming them to be independent and qualitatively similar. Here, we introduce a novel approach suited to handle uncertainties by representing the time series as a time-ordered sequence of probability density functions. We show how to detect abrupt transitions in such a sequence using the community structure of networks representing probabilities of recurrence. Using our approach, we detect transitions in global stock indices related to well-known periods of politico-economic volatility. We further uncover transitions in the El Niño-Southern Oscillation which coincide with periods of phase locking with the Pacific Decadal Oscillation. Finally, we provide for the first time an ‘uncertainty-aware’ framework which validates the hypothesis that ice-rafting events in the North Atlantic during the Holocene were synchronous with a weakened Asian summer monsoon. Y1 - 2018 U6 - https://doi.org/10.1038/s41467-017-02456-6 SN - 2041-1723 VL - 9 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Gellert, Paul A1 - Häusler, Andreas A1 - Suhr, Ralf A1 - Gholami, Maryam A1 - Rapp, Michael A. A1 - Kuhlmey, Adelheid A1 - Nordheim, Johanna T1 - Testing the stress-buffering hypothesis of social support in couples coping with early-stage dementia JF - PLoS one N2 - Purpose: To test whether the negative relationship between perceived stress and quality of life (Hypothesis 1) can be buffered by perceived social support in patients with dementia as well as in caregivers individually (Hypothesis 2: actor effects) and across partners (Hypothesis 3: partner effects and actor-partner effects). Method: A total of 108 couples (N = 216 individuals) comprised of one individual with early-stage dementia and one caregiving partner were assessed at baseline and one month apart. Moderation effects were investigated by applying linear mixed models and actor-partner interdependence models. Results: Although the stress-quality of life association was more pronounced in caregivers (beta = -.63, p<.001) compared to patients (beta= -.31, p<.001), this association was equally moderated by social support in patients (beta = .14, p<.05) and in the caregivers (beta =.13, p<.05). From one partner to his or her counterpart, the partner buffering and actor-partner-buffering effect were not present. Conclusion: The stress-buffering effect has been replicated in individuals with dementia and caregivers but not across partners. Interventions to improve quality of life through perceived social support should not only focus on caregivers, but should incorporate both partners. Y1 - 2018 U6 - https://doi.org/10.1371/journal.pone.0189849 SN - 1932-6203 VL - 13 IS - 1 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Sharma, Niharika A1 - Dang, Trang Minh A1 - Singh, Namrata A1 - Ruzicic, Slobodan A1 - Müller-Röber, Bernd A1 - Baumann, Ute A1 - Heuer, Sigrid T1 - Allelic variants of OsSUB1A cause differential expression of transcription factor genes in response to submergence in rice JF - Rice N2 - Background: Flooding during seasonal monsoons affects millions of hectares of rice-cultivated areas across Asia. Submerged rice plants die within a week due to lack of oxygen, light and excessive elongation growth to escape the water. Submergence tolerance was first reported in an aus-type rice landrace, FR13A, and the ethylene-responsive transcription factor (TF) gene SUB1A-1 was identified as the major tolerance gene. Intolerant rice varieties generally lack the SUB1A gene but some intermediate tolerant varieties, such as IR64, carry the allelic variant SUB1A-2. Differential effects of the two alleles have so far not been addressed. As a first step, we have therefore quantified and compared the expression of nearly 2500 rice TF genes between IR64 and its derived tolerant near isogenic line IR64-Sub1, which carries the SUB1A-1 allele. Gene expression was studied in internodes, where the main difference in expression between the two alleles was previously shown. Results: Nineteen and twenty-six TF genes were identified that responded to submergence in IR64 and IR64-Sub1, respectively. Only one gene was found to be submergence-responsive in both, suggesting different regulatory pathways under submergence in the two genotypes. These differentially expressed genes (DEGs) mainly included MYB, NAC, TIFY and Zn-finger TFs, and most genes were downregulated upon submergence. In IR64, but not in IR64-Sub1, SUB1B and SUB1C, which are also present in the Sub1 locus, were identified as submergence responsive. Four TFs were not submergence responsive but exhibited constitutive, genotype-specific differential expression. Most of the identified submergence responsive DEGs are associated with regulatory hormonal pathways, i.e. gibberellins (GA), abscisic acid (ABA), and jasmonic acid (JA), apart from ethylene. An in-silico promoter analysis of the two genotypes revealed the presence of allele-specific single nucleotide polymorphisms, giving rise to ABRE, DRE/CRT, CARE and Site II cis-elements, which can partly explain the observed differential TF gene expression. Conclusion: This study identified new gene targets with the potential to further enhance submergence tolerance in rice and provides insights into novel aspects of SUB1A-mediated tolerance. KW - Submergence tolerance KW - SUB1A KW - Rice KW - Transcription factors Y1 - 2018 U6 - https://doi.org/10.1186/s12284-017-0192-z SN - 1939-8425 SN - 1939-8433 VL - 11 IS - 2 PB - Springer Open CY - London ER - TY - JOUR A1 - Walter, Judith A1 - Lück, Erika A1 - Bauriegel, Albrecht A1 - Facklam, Michael A1 - Zeitz, Jutta T1 - Seasonal dynamics of soil salinity in peatlands BT - a geophysical approach JF - Geoderma : an international journal of soil science N2 - Inland salt meadows are particularly valuable ecosystems, because they support a variety of salt-adapted species (halophytes). They can be found throughout Europe; including the peatlands of the glacial lowlands in northeast Germany. These German ecosystems have been seriously damaged through drainage. To assess and ultimately limit the damages, temporal monitoring of soil salinity is essential, which can be conducted by geoelectrical techniques that measure the soil electrical conductivity. However, there is limited knowledge on how to interpret electrical conductivity surveys of peaty salt meadows. In this study, temporal and spatial monitoring of dissolved salts was conducted in saline peatland soils using different geoelectrical techniques at different scales (1D: conductivity probe, 2D: conductivity cross-sections). Cores and soil samples were taken to validate the geoelectrical surveys. Although the influence of peat on bulk conductivity is large, the seasonal dynamics of dissolved salts within the soil profile could be monitored by repeated geoelectrical measurements. A close correlation is observed between conductivity (similar to salinity) at different depths and temperature, precipitation and corresponding groundwater level. The conductivity distribution between top- and subsoil during the growing season reflected the leaching of dissolved salts by precipitation and the capillary rise of dissolved salts by increasing temperature (similar to evaporation). Groundwater levels below 0.38 cm resulted in very low conductivities in the topsoil, which is presumably due to limited soil moisture and thus precipitation of salts. Therefore, to prevent the disappearance of dissolved salts from the rooting zone, which are essential for the halophytes, groundwater levels should be adjusted to maintain depths of between 20 and 35 cm. Lower groundwater levels will lead to the loss of dissolved salts from the rooting zone and higher levels to increasing dilution with fresh rainwater. The easy-to-handle conductivity probe is an appropriate tool for salinity monitoring. Using this probe with regressions adjusted for sandy and organic substrates (peat and organic gyttja) additional influences on bulk conductivity (e.g. cation exchange capacity, water content) can be compensated for and the correlation between salinity and electrical conductivity is high. KW - Peatlands KW - Inland salinization KW - Soil salinity dynamics KW - Electrical conductivity KW - Pore-fluid conductivity Y1 - 2017 U6 - https://doi.org/10.1016/j.geoderma.2017.08.022 SN - 0016-7061 SN - 1872-6259 VL - 310 SP - 1 EP - 11 PB - Elsevier Science CY - Amsterdam ER - TY - JOUR A1 - Nitsch, Paula A1 - Kaupenjohann, Martin A1 - Wulf, Monika T1 - Forest continuity, soil depth and tree species are important parameters for SOC stocks in an old forest (Templiner Buchheide, northeast Germany) JF - Geoderma : an international journal of soil science N2 - Forest mineral soils have the potential to accumulate large amounts of carbon (C). Numerous factors, which have often been insufficiently studied, affect soil organic C (SOC) stocks. Detailed knowledge of variation in SOC storage is important to assess the C accumulation potential of forest soils. To examine the impacts of forest continuity, soil depth and tree species on SOC stocks, 15 ancient ( > 230 years of forest continuity) and 15 old ( > 100 but < 200 years of forest continuity) forest soils, topsoil and subsoil in the Templiner Buchheide (Brandenburg, NE Germany) were compared. The old forest sites were afforested on former grassland or wasteland. On all sites grew one of three dominant tree species: European beech (Fagus sylvatica), Scots pine (Pinus sylvestris) or oak (Quercus spec.). Pine forest sites had been underplanted with beech and were mixed-species stands. Soil samples were taken down to a mean depth of 55 cm. Total contents of SOC, nitrogen (N), phosphorus (P), sulphur (S), calcium (Ca), potassium (K) and magnesium (Mg); soil pH; and bulk densities were determined. The soils of ancient forest sites stored significantly more total SOC, N, P, S, K and Mg than did the old ones. Mean total SOC stocks in ancient forests of all three tree species were 12-17% larger compared with those in old forests. Significant differences in SOC stocks between the two forest continuity groups appeared only in subsoil and not in topsoil. Pine forest stored larger SOC stocks than did beech and oak forests. Significant differences were found between ancient pine and oak forests and between ancient beech and oak forests. Soils in ancient beech and pine forests at depths of between 29 and 55 cm contained, on average, even 50% larger SOC stocks than did soils at the same depths in ancient oak forests and in all old forests. Forest continuity significantly affected SOC stocks. These results support previous studies that old forests are still able to enrich SOC. Although soil samples were carried out to a mean depth of only 55 cm, the results indicate that differences in SOC stocks between ancient and old forest could also be found in deeper soil layers. It was suggested that beech and mixed-species stands of beech and pine and total soil P stocks had a positive effect on SOC stocks in subsoil. To understand SOC accumulation in forests, especially in subsoil, with a forest continuity of > 100 years, the role of different tree species and of total P cycling in forests, deeper sampling depths and repeated sampling would be required. KW - Ancient forest KW - C sequestration KW - Land-use history KW - Forest age KW - Total P KW - Subsoil Y1 - 2017 U6 - https://doi.org/10.1016/j.geoderma.2017.08.041 SN - 0016-7061 SN - 1872-6259 VL - 310 SP - 65 EP - 76 PB - Elsevier Science CY - Amsterdam ER - TY - JOUR A1 - Korzeniowska, Karolina A1 - Pfeifer, Norbert A1 - Landtwing, Stephan T1 - Mapping gullies, dunes, lava fields, and landslides via surface roughness JF - Geomorphology : an international journal on pure and applied geomorphology N2 - Gully erosion is a widespread and significant process involved in soil and land degradation. Mapping gullies helps to quantify past, and anticipate future, soil losses. Digital terrain models offer promising data for automatically detecting and mapping gullies especially in vegetated areas, although methods vary widely measures of local terrain roughness are the most varied and debated among these methods. Rarely do studies test the performance of roughness metrics for mapping gullies, limiting their applicability to small training areas. To this end, we systematically explored how local terrain roughness derived from high-resolution Light Detection And Ranging (LiDAR) data can aid in the unsupervised detection of gullies over a large area. We also tested expanding this method for other landforms diagnostic of similarly abrupt land-surface changes, including lava fields, dunes, and landslides, as well as investigating the influence of different roughness thresholds, resolutions of kernels, and input data resolution, and comparing our method with previously published roughness algorithms. Our results show that total curvature is a suitable metric for recognising analysed gullies and lava fields from LiDAR data, with comparable success to that of more sophisticated roughness metrics. Tested dunes or landslides remain difficult to distinguish from the surrounding landscape, partly because they are not easily defined in terms of their topographic signature. KW - Gullies KW - Surface roughness KW - Curvature KW - Digital terrain model (DTM) KW - LiDAR KW - Geomorphometry Y1 - 2017 U6 - https://doi.org/10.1016/j.geomorph.2017.10.011 SN - 0169-555X SN - 1872-695X VL - 301 SP - 53 EP - 67 PB - Elsevier Science CY - Amsterdam ER - TY - JOUR A1 - Giulbudagian, Michael A1 - Hönzke, Stefan A1 - Bergueiro, Julián A1 - Işık, Doğuş A1 - Schumacher, Fabian A1 - Saeidpour, Siavash A1 - Lohan, Silke A1 - Meinke, Martina A1 - Teutloff, Christian A1 - Schäfer-Korting, Monika A1 - Yealland, Guy A1 - Kleuser, Burkhard A1 - Hedtrich, Sarah A1 - Calderón, Marcelo T1 - Enhanced topical delivery of dexamethasone by beta-cyclodextrin decorated thermoresponsive nanogels JF - Nanoscale N2 - Highly hydrophilic, responsive nanogels are attractive as potential systems for the topical delivery of bioactives encapsulated in their three-dimensional polymeric scaffold. Yet, these drug carrier systems suffer from drawbacks for efficient delivery of hydrophobic drugs. Addressing this, β-cyclodextrin (βCD) could be successfully introduced into the drug carrier systems by exploiting its unique affinity toward dexamethasone (DXM) as well as its role as topical penetration enhancer. The properties of βCD could be combined with those of thermoresponsive nanogels (tNGs) based on dendritic polyglycerol (dPG) as a crosslinker and linear thermoresponsive polyglycerol (tPG) inducing responsiveness to temperature changes. Electron paramagnetic resonance (EPR) studies localized the drug within the hydrophobic cavity of βCD by differences in its mobility and environmental polarity. In fact, the fabricated carriers combining a particulate delivery system with a conventional penetration enhancer, resulted in an efficient delivery of DXM to the epidermis and the dermis of human skin ex vivo (enhancement compared to commercial DXM cream: ∼2.5 fold in epidermis, ∼30 fold in dermis). Furthermore, DXM encapsulated in βCD tNGs applied to skin equivalents downregulated the expression of proinflammatory thymic stromal lymphopoietin (TSLP) and outperformed a commercially available DXM cream. Y1 - 2017 U6 - https://doi.org/10.1039/c7nr04480a SN - 2040-3364 SN - 2040-3372 VL - 10 IS - 1 SP - 469 EP - 479 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Aydiner, Ekrem A1 - Cherstvy, Andrey G. A1 - Metzler, Ralf T1 - Wealth distribution, Pareto law, and stretched exponential decay of money BT - Computer simulations analysis of agent-based models JF - Physica : europhysics journal ; A, Statistical mechanics and its applications N2 - We study by Monte Carlo simulations a kinetic exchange trading model for both fixed and distributed saving propensities of the agents and rationalize the person and wealth distributions. We show that the newly introduced wealth distribution – that may be more amenable in certain situations – features a different power-law exponent, particularly for distributed saving propensities of the agents. For open agent-based systems, we analyze the person and wealth distributions and find that the presence of trap agents alters their amplitude, leaving however the scaling exponents nearly unaffected. For an open system, we show that the total wealth – for different trap agent densities and saving propensities of the agents – decreases in time according to the classical Kohlrausch–Williams–Watts stretched exponential law. Interestingly, this decay does not depend on the trap agent density, but rather on saving propensities. The system relaxation for fixed and distributed saving schemes are found to be different. KW - Econophysics KW - Wealth and income distribution KW - Pareto law KW - Scaling exponents Y1 - 2017 U6 - https://doi.org/10.1016/j.physa.2017.08.017 SN - 0378-4371 SN - 1873-2119 VL - 490 SP - 278 EP - 288 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Davidzon, Iary A1 - Ilbert, Olivier A1 - Faisst, Andreas L. A1 - Sparre, Martin A1 - Capak, Peter L. T1 - An Alternate Approach to Measure Specific Star Formation Rates at 2 < z < 7 JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We trace the specific star formation rate (sSFR) of massive star-forming galaxies (greater than or similar to 10(10)M(circle dot)) from z similar to 2 to 7. Our method is substantially different from previous analyses, as it does not rely on direct estimates of star formation rate, but on the differential evolution of the galaxy stellar mass function (SMF). We show the reliability of this approach by means of semianalytical and hydrodynamical cosmological simulations. We then apply it to real data, using the SMFs derived in the COSMOS and CANDELS fields. We find that the sSFR is proportional to (1 + z)(1.1) (+/-) (0.2) at z > 2, in agreement with other observations but in tension with the steeper evolution predicted by simulations from z similar to 4 to 2. We investigate the impact of several sources of observational bias, which, however, cannot account for this discrepancy. Although the SMF of high-redshift galaxies is still affected by significant errors, we show that future large-area surveys will substantially reduce them, making our method an effective tool to probe the massive end of the main sequence of star-forming galaxies. KW - galaxies: evolution KW - galaxies: high-redshift KW - galaxies: star formation Y1 - 2018 U6 - https://doi.org/10.3847/1538-4357/aaa19e SN - 0004-637X SN - 1538-4357 VL - 852 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Ni, Binbin A1 - Cao, Xing A1 - Shprits, Yuri A1 - Summers, Danny A1 - Gu, Xudong A1 - Fu, Song A1 - Lou, Yuequn T1 - Hot Plasma Effects on the Cyclotron-Resonant Pitch-Angle Scattering Rates of Radiation Belt Electrons Due to EMIC Waves JF - Geophysical research letters N2 - To investigate the hot plasma effects on the cyclotron-resonant interactions between electromagnetic ion cyclotron (EMIC) waves and radiation belt electrons in a realistic magnetospheric environment, calculations of the wave-induced bounce-averaged pitch angle diffusion coefficients are performed using both the cold and hot plasma dispersion relations. The results demonstrate that the hot plasma effects have a pronounced influence on the electron pitch angle scattering rates due to all three EMIC emission bands (H+, He+, and O+) when the hot plasma dispersion relation deviates significantly from the cold plasma approximation. For a given wave spectrum, the modification of the dispersion relation by hot anisotropic protons can strongly increase the minimum resonant energy for electrons interacting with O+ band EMIC waves, while the minimum resonant energies for H+ and He+ bands are not greatly affected. For H+ band EMIC waves, inclusion of hot protons tends to weaken the pitch angle scattering efficiency of >5MeV electrons. The most crucial differences introduced by the hot plasma effects occur for >3MeV electron scattering rates by He+ band EMIC waves. Mainly due to the changes of resonant frequency and wave group velocity when the hot protons are included, the difference in scattering rates can be up to an order of magnitude, showing a strong dependence on both electron energy and equatorial pitch angle. Our study confirms the importance of including hot plasma effects in modeling the scattering of ultra-relativistic radiation belt electrons by EMIC waves. Y1 - 2018 U6 - https://doi.org/10.1002/2017GL076028 SN - 0094-8276 SN - 1944-8007 VL - 45 IS - 1 SP - 21 EP - 30 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Laepple, Thomas A1 - Münch, Thomas A1 - Casado, Mathieu A1 - Hoerhold, Maria A1 - Landais, Amaelle A1 - Kipfstuhl, Sepp T1 - On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits JF - The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union N2 - Stable isotope ratios delta O-18 and delta D in polar ice provide a wealth of information about past climate evolution. Snow-pit studies allow us to relate observed weather and climate conditions to the measured isotope variations in the snow. They therefore offer the possibility to test our understanding of how isotope signals are formed and stored in firn and ice. As delta O-18 and delta D in the snowfall are strongly correlated to air temperature, isotopes in the near-surface snow are thought to record the seasonal cycle at a given site. Accordingly, the number of seasonal cycles observed over a given depth should depend on the accumulation rate of snow. However, snow-pit studies from different accumulation conditions in East Antarctica reported similar isotopic variability and comparable apparent cycles in the delta O-18 and delta D profiles with typical wavelengths of similar to 20 cm. These observations are unexpected as the accumulation rates strongly differ between the sites, ranging from 20 to 80mmw.e.yr(-1) (similar to 6-21 cm of snow per year). Various mechanisms have been proposed to explain the isotopic variations individually at each site; however, none of these are consistent with the similarity of the different profiles independent of the local accumulation conditions. Here, we systematically analyse the properties and origins of delta O-18 and delta D variations in high-resolution firn profiles from eight East Antarctic sites. First, we confirm the suggested cycle length (mean distance between peaks) of similar to 20 cm by counting the isotopic maxima. Spectral analysis further shows a strong similarity between the sites but indicates no dominant periodic features. Furthermore, the appar-ent cycle length increases with depth for most East Antarctic sites, which is inconsistent with burial and compression of a regular seasonal cycle. We show that these results can be explained by isotopic diffusion acting on a noise-dominated isotope signal. The firn diffusion length is rather stable across the Antarctic Plateau and thus leads to similar power spectral densities of the isotopic variations. This in turn implies a similar distance between isotopic maxima in the firn profiles. Our results explain a large set of observations discussed in the literature, providing a simple explanation for the interpretation of apparent cycles in shallow isotope records, without invoking complex mechanisms. Finally, the results underline previous suggestions that isotope signals in single ice cores from low-accumulation regions have a small signal-to-noise ratio and thus likely do not allow the reconstruction of interannual to decadal climate variations. Y1 - 2018 U6 - https://doi.org/10.5194/tc-12-169-2018 SN - 1994-0416 SN - 1994-0424 VL - 12 IS - 1 SP - 169 EP - 187 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Krüger, Stefanie A1 - Schwarze, Michael A1 - Baumann, Otto A1 - Günter, Christina A1 - Bruns, Michael A1 - Kübel, Christian A1 - Szabo, Dorothee Vinga A1 - Meinusch, Rafael A1 - Bermudez, Veronica de Zea A1 - Taubert, Andreas T1 - Bombyx mori silk/titania/gold hybrid materials for photocatalytic water splitting BT - combining renewable raw materials with clean fuels JF - Beilstein journal of nanotechnology N2 - The synthesis, structure, and photocatalytic water splitting performance of two new titania (TiO2)/gold(Au)/Bombyx mori silk hybrid materials are reported. All materials are monoliths with diameters of up to ca. 4.5 cm. The materials are macroscopically homogeneous and porous with surface areas between 170 and 210 m(2)/g. The diameter of the TiO2 nanoparticles (NPs) - mainly anatase with a minor fraction of brookite - and the Au NPs are on the order of 5 and 7-18 nm, respectively. Addition of poly(ethylene oxide) to the reaction mixture enables pore size tuning, thus providing access to different materials with different photocatalytic activities. Water splitting experiments using a sunlight simulator and a Xe lamp show that the new hybrid materials are effective water splitting catalysts and produce up to 30 mmol of hydrogen per 24 h. Overall the article demonstrates that the combination of a renewable and robust scaffold such as B. mori silk with a photoactive material provides a promising approach to new monolithic photocatalysts that can easily be recycled and show great potential for application in lightweight devices for green fuel production. KW - Bombyx mori silk KW - gold KW - photocatalytic water splitting KW - titania Y1 - 2018 U6 - https://doi.org/10.3762/bjnano.9.21 SN - 2190-4286 VL - 9 SP - 187 EP - 204 PB - Beilstein-Institut zur Förderung der Chemischen Wissenschaften CY - Frankfurt, Main ER - TY - JOUR A1 - Tucker, Marlee A. A1 - Boehning-Gaese, Katrin A1 - Fagan, William F. A1 - Fryxell, John M. A1 - Van Moorter, Bram A1 - Alberts, Susan C. A1 - Ali, Abdullahi H. A1 - Allen, Andrew M. A1 - Attias, Nina A1 - Avgar, Tal A1 - Bartlam-Brooks, Hattie A1 - Bayarbaatar, Buuveibaatar A1 - Belant, Jerrold L. A1 - Bertassoni, Alessandra A1 - Beyer, Dean A1 - Bidner, Laura A1 - van Beest, Floris M. A1 - Blake, Stephen A1 - Blaum, Niels A1 - Bracis, Chloe A1 - Brown, Danielle A1 - de Bruyn, P. J. Nico A1 - Cagnacci, Francesca A1 - Calabrese, Justin M. A1 - Camilo-Alves, Constanca A1 - Chamaille-Jammes, Simon A1 - Chiaradia, Andre A1 - Davidson, Sarah C. A1 - Dennis, Todd A1 - DeStefano, Stephen A1 - Diefenbach, Duane A1 - Douglas-Hamilton, Iain A1 - Fennessy, Julian A1 - Fichtel, Claudia A1 - Fiedler, Wolfgang A1 - Fischer, Christina A1 - Fischhoff, Ilya A1 - Fleming, Christen H. A1 - Ford, Adam T. A1 - Fritz, Susanne A. A1 - Gehr, Benedikt A1 - Goheen, Jacob R. A1 - Gurarie, Eliezer A1 - Hebblewhite, Mark A1 - Heurich, Marco A1 - Hewison, A. J. Mark A1 - Hof, Christian A1 - Hurme, Edward A1 - Isbell, Lynne A. A1 - Janssen, Rene A1 - Jeltsch, Florian A1 - Kaczensky, Petra A1 - Kane, Adam A1 - Kappeler, Peter M. A1 - Kauffman, Matthew A1 - Kays, Roland A1 - Kimuyu, Duncan A1 - Koch, Flavia A1 - Kranstauber, Bart A1 - LaPoint, Scott A1 - Leimgruber, Peter A1 - Linnell, John D. C. A1 - Lopez-Lopez, Pascual A1 - Markham, A. Catherine A1 - Mattisson, Jenny A1 - Medici, Emilia Patricia A1 - Mellone, Ugo A1 - Merrill, Evelyn A1 - Mourao, Guilherme de Miranda A1 - Morato, Ronaldo G. A1 - Morellet, Nicolas A1 - Morrison, Thomas A. A1 - Diaz-Munoz, Samuel L. A1 - Mysterud, Atle A1 - Nandintsetseg, Dejid A1 - Nathan, Ran A1 - Niamir, Aidin A1 - Odden, John A1 - Oliveira-Santos, Luiz Gustavo R. A1 - Olson, Kirk A. A1 - Patterson, Bruce D. A1 - de Paula, Rogerio Cunha A1 - Pedrotti, Luca A1 - Reineking, Bjorn A1 - Rimmler, Martin A1 - Rogers, Tracey L. A1 - Rolandsen, Christer Moe A1 - Rosenberry, Christopher S. A1 - Rubenstein, Daniel I. A1 - Safi, Kamran A1 - Said, Sonia A1 - Sapir, Nir A1 - Sawyer, Hall A1 - Schmidt, Niels Martin A1 - Selva, Nuria A1 - Sergiel, Agnieszka A1 - Shiilegdamba, Enkhtuvshin A1 - Silva, Joao Paulo A1 - Singh, Navinder A1 - Solberg, Erling J. A1 - Spiegel, Orr A1 - Strand, Olav A1 - Sundaresan, Siva A1 - Ullmann, Wiebke A1 - Voigt, Ulrich A1 - Wall, Jake A1 - Wattles, David A1 - Wikelski, Martin A1 - Wilmers, Christopher C. A1 - Wilson, John W. A1 - Wittemyer, George A1 - Zieba, Filip A1 - Zwijacz-Kozica, Tomasz A1 - Mueller, Thomas T1 - Moving in the Anthropocene BT - global reductions in terrestrial mammalian movements JF - Science N2 - Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission. Y1 - 2018 U6 - https://doi.org/10.1126/science.aam9712 SN - 0036-8075 SN - 1095-9203 VL - 359 IS - 6374 SP - 466 EP - 469 PB - American Assoc. for the Advancement of Science CY - Washington ER - TY - JOUR A1 - Schmidt, Bernd A1 - Schultze, Christiane T1 - A one-pot synthesis of pyranocoumarins through microwave-promoted propargyl claisen rearrangement/wittig olefination JF - European journal of organic chemistry N2 - The reaction between propargyl ethers of hydroxybenzaldehydes and the ylide ethyl (triphenylphosphoranylidene)acetate was carried out under microwave irradiation to regioselectively afford angular pyranocoumarins. The chromene and coumarin heterocyclic scaffolds were simultaneously formed in the same synthetic step without changing the reaction conditions. The natural products seselin, braylin, and dipetalolactone were among the products synthesized by this method. KW - Domino reactions KW - Alkynes KW - Arenes KW - Oxygen heterocycles KW - Microwave chemistry KW - Rearrangement Y1 - 2017 SN - 1434-193X SN - 1099-0690 VL - 2018 IS - 2 SP - 223 EP - 227 PB - Wiley-VCH Verl. CY - Weinheim ER - TY - JOUR A1 - Guber, Christoph Rudolf A1 - Richter, Philipp A1 - Wendt, Martin T1 - Multiple origins for the DLA at zabs = 0.313 toward PKS 1127–145 indicated by a complex dust depletion pattern of Ca, Ti, and Mn JF - Astronomy and astrophysics : an international weekly journal N2 - Aims: We aim to investigate the dust depletion properties of optically thick gas in and around galaxies and its origin we study in detail the dust depletion patterns of Ti, Mn, and Ca in the multi-component damped Lyman alpha (DLA) absorber at z(abs) = 0.313 toward the quasar PKS 1127-145. Methods: We performed a detailed spectral analysis of the absorption profiles of Ca II, Mn II, TIII, and Na I associated with the DLA toward PKS 1127-145, based on optical high-resolution data obtained with the UVES instrument at the Very Large Telescope. We obtained column densities and Doppler-parameters for the ions listed above and determine their gas-phase abundances, from which we conclude on their dust depletion properties. We compared the Ca and Ti depletion properties of this DLA with that of other DLAs. Results: One of the six analyzed absorption components (component 3) shows a striking underabundance of Ti and Mn in the gas-phase, indicating the effect of dust depletion for these elements and a locally enhanced dust-to-gas ratio. In this DLA and in other similar absorbers, the Mn II abundance follows that of Ti II very closely, implying that both ions are equally sensitive to the dust depletion effects. Conclusions: Our analysis indicates that the DLA toward PKS 1127 145 has multiple origins. With its narrow line width and its strong dust depletion, component 3 points toward the presence of a neutral gas disk from a faint LSB galaxy in front of PKS 1127 145, while the other, more diffuse and dust-poor, absorption components possibly are related to tidal gas features from the interaction between the various, optically confirmed galaxy-group members. In general, the Mn/Ca II ratio in sub-DLAs and DLAs possibly serves as an important indicator to discriminate between dust-rich and dust-poor in neutral gas in and around galaxies. KW - quasars: absorption lines KW - galaxies: abundances KW - intergalactic medium KW - quasars: individual: PKS1127-145 KW - dust, extinction KW - ISM: kinematics and dynamics Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201730984 SN - 1432-0746 VL - 609 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Hainich, Rainer A1 - Oskinova, Lidia M. A1 - Shenar, Tomer A1 - Marchant Campos, Pablo A1 - Eldridge, J. J. A1 - Sander, Andreas Alexander Christoph A1 - Hamann, Wolf-Rainer A1 - Langer, Norbert A1 - Todt, Helge Tobias T1 - Observational properties of massive black hole binary progenitors JF - Astronomy and astrophysics : an international weekly journal N2 - Context: The first directly detected gravitational waves (GW 150914) were emitted by two coalescing black holes (BHs) with masses of ≈ 36 M⊙ and ≈ 29 M⊙. Several scenarios have been proposed to put this detection into an astrophysical context. The evolution of an isolated massive binary system is among commonly considered models. Aims: Various groups have performed detailed binary-evolution calculations that lead to BH merger events. However, the question remains open as to whether binary systems with the predicted properties really exist. The aim of this paper is to help observers to close this gap by providing spectral characteristics of massive binary BH progenitors during a phase where at least one of the companions is still non-degenerate. Methods: Stellar evolution models predict fundamental stellar parameters. Using these as input for our stellar atmosphere code (Potsdam Wolf-Rayet), we compute a set of models for selected evolutionary stages of massive merging BH progenitors at different metallicities. Results: The synthetic spectra obtained from our atmosphere calculations reveal that progenitors of massive BH merger events start their lives as O2-3V stars that evolve to early-type blue supergiants before they undergo core-collapse during the Wolf-Rayet phase. When the primary has collapsed, the remaining system will appear as a wind-fed high-mass X-ray binary. Based on our atmosphere models, we provide feedback parameters, broad band magnitudes, and spectral templates that should help to identify such binaries in the future. Conclusions: While the predicted parameter space for massive BH binary progenitors is partly realized in nature, none of the known massive binaries match our synthetic spectra of massive BH binary progenitors exactly. Comparisons of empirically determined mass-loss rates with those assumed by evolution calculations reveal significant differences. The consideration of the empirical mass-loss rates in evolution calculations will possibly entail a shift of the maximum in the predicted binary-BH merger rate to higher metallicities, that is, more candidates should be expected in our cosmic neighborhood than previously assumed. KW - gravitational waves KW - binaries: close KW - stars: early-type KW - stars: atmospheres KW - stars: winds KW - outflows KW - stars: mass-loss Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201731449 SN - 1432-0746 VL - 609 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Synodinos, Alexis D. A1 - Tietjen, Britta A1 - Lohmann, Dirk A1 - Jeltsch, Florian T1 - The impact of inter-annual rainfall variability on African savannas changes with mean rainfall JF - Journal of theoretical biology N2 - Savannas are mixed tree-grass ecosystems whose dynamics are predominantly regulated by resource competition and the temporal variability in climatic and environmental factors such as rainfall and fire. Hence, increasing inter-annual rainfall variability due to climate change could have a significant impact on savannas. To investigate this, we used an ecohydrological model of stochastic differential equations and simulated African savanna dynamics along a gradient of mean annual rainfall (520–780 mm/year) for a range of inter-annual rainfall variabilities. Our simulations produced alternative states of grassland and savanna across the mean rainfall gradient. Increasing inter-annual variability had a negative effect on the savanna state under dry conditions (520 mm/year), and a positive effect under moister conditions (580–780 mm/year). The former resulted from the net negative effect of dry and wet extremes on trees. In semi-arid conditions (520 mm/year), dry extremes caused a loss of tree cover, which could not be recovered during wet extremes because of strong resource competition and the increased frequency of fires. At high mean rainfall (780 mm/year), increased variability enhanced savanna resilience. Here, resources were no longer limiting and the slow tree dynamics buffered against variability by maintaining a stable population during ‘dry’ extremes, providing the basis for growth during wet extremes. Simultaneously, high rainfall years had a weak marginal benefit on grass cover due to density-regulation and grazing. Our results suggest that the effects of the slow tree and fast grass dynamics on tree-grass interactions will become a major determinant of the savanna vegetation composition with increasing rainfall variability. KW - Rainfall variability KW - Savanna-grassland bistability KW - Stochastic differential equations KW - Coexistence mechanisms KW - Fire Y1 - 2017 U6 - https://doi.org/10.1016/j.jtbi.2017.10.019 SN - 0022-5193 SN - 1095-8541 VL - 437 SP - 92 EP - 100 PB - Elsevier Ltd. CY - London ER - TY - JOUR A1 - Zellmeier, M. A1 - Brenner, Thomas J. K. A1 - Janietz, Silvia A1 - Nickel, N. H. A1 - Rappich, J. T1 - Polythiophenes as emitter layers for crystalline silicon solar cells BT - parasitic absorption, interface passivation, and open circuit voltage JF - Journal of applied physics N2 - We investigated the influence of the emitter (amorphous-Si, a-Si, or polythiophene derivatives: poly(3-hexylthiophene), P3HT, and poly(3-[3,6-dioxaheptyl]-thiophene), P3DOT) and the interface passivation (intrinsic a-Si or SiOX and methyl groups or SiOX) on the c-Si based 1 × 1 cm2 planar hybrid heterojunction solar cell parameters. We observed higher short circuit currents for the P3HT or P3DOT/c-Si solar cells than those obtained for a-Si/c-Si devices, independent of the interface passivation. The obtained VOC of 659 mV for the P3DOT/SiOX/c-Si heterojunction solar cell with hydrophilic 3,6-dioxaheptyl side chains is among the highest reported for c-Si/polythiophene devices. The maximum power conversion efficiency, PCE, was 11% for the P3DOT/SiOX/c-Si heterojunction solar cell. Additionally, our wafer lifetime measurements reveal a field effect passivation in the wafer induced by the polythiophenes when deposited on c-Si. Y1 - 2018 U6 - https://doi.org/10.1063/1.5006625 SN - 0021-8979 SN - 1089-7550 VL - 123 IS - 3 PB - American Institute of Physics CY - Melville ER - TY - JOUR A1 - Fujikura, Ushio A1 - Jing, Runchun A1 - Hanada, Atsushi A1 - Takebayashi, Yumiko A1 - Sakakibara, Hitoshi A1 - Yamaguchi, Shinjiro A1 - Kappel, Christian A1 - Lenhard, Michael T1 - Variation in splicing efficiency underlies morphological evolution in capsella JF - Developmental cell N2 - Understanding the molecular basis of morphological change remains a central challenge in evolutionary-developmental biology. The transition from outbreeding to selfing is often associated with a dramatic reduction in reproductive structures and functions, such as the loss of attractive pheromones in hermaphroditic Caenorhabditis elegans and a reduced flower size in plants. Here, we demonstrate that variation in the level of the brassinosteroid-biosynthesis enzyme CYP724A1 contributes to the reduced flower size of selfing Capsella rubella compared with its outbreeding ancestor Capsella grandiflora. The primary transcript of the C. rubella allele is spliced more efficiently than that of C. grandiflora, resulting in higher brassinosteroid levels. These restrict organ growth by limiting cell proliferation. More efficient splicing of the C. rubella allele results from two de novo mutations in the selfing lineage. Thus, our results highlight the potentially widespread importance of differential splicing efficiency and higher-than-optimal hormone levels in generating phenotypic variation. Y1 - 2017 U6 - https://doi.org/10.1016/j.devcel.2017.11.022 SN - 1534-5807 SN - 1878-1551 VL - 44 IS - 2 SP - 192 EP - 203 PB - Cell Press CY - Cambridge ER - TY - JOUR A1 - Wolf, Isabell Ann-Cathrin A1 - Gilles, Maria A1 - Peus, Verena A1 - Scharnholz, Barbara A1 - Seibert, Julia A1 - Jennen-Steinmetz, Christine A1 - Krumm, Bertram A1 - Rietschel, Marcella A1 - Deuschle, Michael A1 - Laucht, Manfred T1 - Impact of prenatal stress on mother-infant dyadic behavior during the still-face paradigm JF - Borderline Personality Disorder and Emotion Dysregulation : the official journal of the National Education Alliance for Borderline Personality Disorder (NEA.BPD) and Dachverband Dialektisch Behaviorale Therapie (DDBT) N2 - Background: Mother-infant interaction provides important training for the infant’s ability to cope with stress and the development of resilience. Prenatal stress (PS) and its impact on the offspring’s development have long been a focus of stress research, with studies highlighting both harmful and beneficial effects. The aim of the current study was to examine the possible influence of both psychological stress and hypothalamic-pituitary-adrenal (HPA) axis activity during pregnancy with mother-child dyadic behavior following stress exposure. Methods: The behavior of 164 mother-infant dyads during the still-face situation was filmed at six months postpartum and coded into three dyadic patterns: 1) both positive, 2) infant protesting-mother positive, and 3) infant protesting-mother negative. PS exposure was assessed prenatally according to psychological measures (i.e., psychopathological, perceived and psychosocial PS; n = 164) and HPA axis activity measures (maternal salivary cortisol, i.e., cortisol decline and area under the curve with respect to ground (AUCg); n = 134). Results: Mother-infant dyads in both the high- and low-stress groups showed decreasing positive and increasing negative dyadic behavior in the reunion episode, which is associated with the well-known “still-face” and “carry-over” effect. Furthermore, mother-infant dyads with higher psychosocial PS exhibited significantly more positive dyadic behavior than the low psychosocial PS group in the first play episode, but not in the reunion episode. Similarly, mother-infant dyads with high HPA axis activity (i.e. high AUCg) but steeper diurnal cortisol decline (i.e. cortisol decline) displayed significantly less negative behavior in the reunion episode than dyads with low HPA axis activity. No significant results were found for psychopathological stress and perceived stress. Conclusions: The results suggest a beneficial effect of higher psychosocial PS and higher prenatal maternal HPA axis activity in late gestation, which is in line with “stress inoculation” theories. KW - Prenatal stress KW - Face-to-face still-face paradigm KW - Resilience KW - Psychosocial stress KW - Cortisol Y1 - 2018 U6 - https://doi.org/10.1186/s40479-018-0078-8 SN - 2051-6673 VL - 5 PB - BioMed Central CY - London ER - TY - JOUR A1 - Vater, Aline A1 - Moritz, Steffen A1 - Roepke, Stefan T1 - Does a narcissism epidemic exist in modern western societies? BT - Comparing narcissism and self-esteem in East and West Germany JF - PLOS ONE N2 - Narcissism scores are higher in individualistic cultures compared with more collectivistic cultures. However, the impact of sociocultural factors on narcissism and self-esteem has not been well described. Germany was formerly divided into two different social systems, each with distinct economic, political and national cultures, and was reunified in 1989/90. Between 1949 and 1989/90, West Germany had an individualistic culture, whereas East Germany had a more collectivistic culture. The German reunification provides an exceptional opportunity to investigate the impact of sociocultural and generational differences on narcissism and self-esteem. In this study, we used an anonymous online survey to assess grandiose narcissism with the Narcissistic Personality Inventory (NPI) and the Pathological Narcissism Inventory (PNI) to assess grandiose and vulnerable aspects of narcissism, and self-esteem with the Rosenberg Self-Esteem Scale (RSE) in 1,025 German individuals. Data were analyzed according to age and place of birth. Our results showed that grandiose narcissism was higher and self-esteem was lower in individuals who grew up in former West Germany compared with former East Germany. Further analyses indicated no significant differences in grandiose narcissism, vulnerable narcissism or self-esteem in individuals that entered school after the German reunification (≤ 5 years of age in 1989). In the middle age cohort (6–18 years of age in 1989), significant differences in vulnerable narcissism, grandiose narcissism and self-esteem were observed. In the oldest age cohort (> 19 years of age in 1989), significant differences were only found in one of the two scales assessing grandiose narcissism (NPI). Our data provides empirical evidence that sociocultural factors are associated with differences in narcissism and self-esteem. Y1 - 2018 U6 - https://doi.org/10.1371/journal.pone.0188287 SN - 1932-6203 VL - 13 IS - 1 PB - Public Library of Science CY - San Fransisco ER - TY - JOUR A1 - Sustr, David A1 - Hlaváček, Antonín A1 - Duschl, Claus A1 - Volodkin, Dmitry T1 - Multi-fractional analysis of molecular diffusion in polymer multilayers by FRAP BT - a new simulation-based approach JF - The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces & biophysical N2 - Comprehensive analysis of the multifractional molecular diffusion provides a deeper understanding of the diffusion phenomenon in the fields of material science, molecular and cell biology, advanced biomaterials, etc. Fluorescence recovery after photobleaching (FRAP) is commonly employed to probe the molecular diffusion. Despite FRAP being a very popular method, it is not easy to assess multifractional molecular diffusion due to limited possibilities of approaches for analysis. Here we present a novel simulation-optimization-based approach (S-approach) that significantly broadens possibilities of the analysis. In the S-approach, possible fluorescence recovery scenarios are primarily simulated and afterward compared with a real measurement while optimizing parameters of a model until a sufficient match is achieved. This makes it possible to reveal multifractional molecular diffusion. Fluorescent latex particles of different size and fluorescein isothiocyanate in an aqueous medium were utilized as test systems. Finally, the S-approach has been used to evaluate diffusion of cytochrome c loaded into multilayers made of hyaluronan and polylysine. Software for evaluation of multifractional molecular diffusion by S-approach has been developed aiming to offer maximal versatility and user-friendly way for analysis. Y1 - 2017 U6 - https://doi.org/10.1021/acs.jpcb.7b11051 SN - 1520-6106 VL - 122 IS - 3 SP - 1323 EP - 1333 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Küçükgöze, Gökhan A1 - Leimkühler, Silke T1 - Direct comparison of the four aldehyde oxidase enzymes present in mouse gives insight into their substrate specificities JF - PLOS ONE N2 - Mammalian aldehyde oxidases (AOXs) are molybdo-flavoenzymes which are present in many tissues in various mammalian species, including humans and rodents. Different species contain a different number of AOX isoforms. In particular, the reasons why mammals other than humans express a multiplicity of tissue-specific AOX enzymes is unknown. In mouse, the isoforms mAOX1, mAOX3, mAOX4 and mAOX2 are present. We previously established a codon-optimized heterologous expression systems for the mAOX1-4 isoforms in Escherichia coli that gives yield to sufficient amounts of active protein for kinetic characterizations and sets the basis in this study for site-directed mutagenesis and structure-function studies. A direct and simultaneous comparison of the enzymatic properties and characteristics of the four enzymes on a larger number of substrates has never been performed. Here, thirty different structurally related aromatic, aliphatic and N-heterocyclic compounds were used as substrates, and the kinetic parameters of all four mAOX enzymes were directly compared. The results show that especially mAOX4 displays a higher substrate selectivity, while no major differences between mAOX1, mAOX2 and mAOX3 were identified. Generally, mAOX1 was the enzyme with the highest catalytic turnover for most substrates. To understand the factors that contribute to the substrate specificity of mAOX4, site-directed mutagenesis was applied to substitute amino acids in the substrate-binding funnel by the ones present in mAOX1, mAOX3, and mAOX2. An increase in activity was obtained by the amino acid exchange M1088V in the active site identified to be specific for mAOX4, to the amino acid identified in mAOX3. Y1 - 2018 U6 - https://doi.org/10.1371/journal.pone.0191819 SN - 1932-6203 VL - 13 IS - 1 PB - Public Library of Science CY - San Fransisco ER - TY - JOUR A1 - Xiong, Tao A1 - Włodarczyk, Radosław Stanisław A1 - Gallandi, Lukas A1 - Körzdörfer, Thomas A1 - Saalfrank, Peter T1 - Vibrationally resolved photoelectron spectra of lower diamondoids BT - a time-dependent approach JF - The journal of chemical physics : bridges a gap between journals of physics and journals of chemistry N2 - Vibrationally resolved lowest-energy bands of the photoelectron spectra (PES) of adamantane, diamantane, and urotropine were simulated by a time-dependent correlation function approach within the harmonic approximation. Geometries and normal modes for neutral and cationic molecules were obtained from B3LYP hybrid density functional theory (DFT). It is shown that the simulated spectra reproduce the experimentally observed vibrational finestructure (or its absence) quite well. Origins of the finestructure are discussed and related to recurrences of autocorrelation functions and dominant vibrations. Remaining quantitative and qualitative errors of the DFT-derived PES spectra refer to (i) an overall redshift by ∼0.5 eV and (ii) the absence of satellites in the high-energy region of the spectra. The former error is shown to be due to the neglect of many-body corrections to ordinary Kohn-Sham methods, while the latter has been argued to be due to electron-nuclear couplings beyond the Born-Oppenheimer approximation [Gali et al., Nat. Commun. 7, 11327 (2016)]. Y1 - 2018 U6 - https://doi.org/10.1063/1.5012131 SN - 0021-9606 SN - 1089-7690 VL - 148 IS - 4 PB - American Institute of Physics CY - Melville ER - TY - JOUR A1 - Pikovskij, Arkadij T1 - Reconstruction of a random phase dynamics network from observations JF - Physics letters : A N2 - We consider networks of coupled phase oscillators of different complexity: Kuramoto–Daido-type networks, generalized Winfree networks, and hypernetworks with triple interactions. For these setups an inverse problem of reconstruction of the network connections and of the coupling function from the observations of the phase dynamics is addressed. We show how a reconstruction based on the minimization of the squared error can be implemented in all these cases. Examples include random networks with full disorder both in the connections and in the coupling functions, as well as networks where the coupling functions are taken from experimental data of electrochemical oscillators. The method can be directly applied to asynchronous dynamics of units, while in the case of synchrony, additional phase resettings are necessary for reconstruction. KW - Phase dynamics KW - Network reconstruction Y1 - 2017 U6 - https://doi.org/10.1016/j.physleta.2017.11.012 SN - 0375-9601 SN - 1873-2429 VL - 382 IS - 4 SP - 147 EP - 152 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Omrani, Hadi A1 - Moazzen, Mohssen A1 - Oberhänsli, Roland T1 - Geodynamic evolution of the Sabzevar zone, northern central Iranian micro-continent JF - Mineralogy and petrology N2 - The Northern Central Iranian Micro-continent (CIM) represents Neotethys-related oceanic crust remnants, emplaced due to convergence between CIM and Eurasia plates during Eocene. Mafic and ultramafic units are exposed along the northern part of the CIM in the Sabzevar area. The geology and field relation of Sabzevar ophiolite indicate northward subduction of the Sabzevar basin. The average whole rock chemistry of mafic (gabbros) and ultramafic samples (lherzolite, harzburgite and dunite) is characterized by a range of MgO of 11.16-31.88, CaO 5.22-11.53 and Al2O3 2.77-14.57, respectively. Low LREE/HREE ratio of ultramafic samples is accompanied by enrichment of large ion lithophile elements (LILE) such as Sr, Pb and K. Mafic samples show two distinct groups with low and high LREE/HREE ratios. The spider diagram of mafic samples indicates enrichment in Sr, Pb and K and depletion in REE. Petrological and geochemical evidence and field relations show that the mafic rocks formed in a supra-subduction zone setting. Petrological studies reveal the role of fractional crystallization and assimilation effect by released fluids during subduction related generation of the Sabzevar mafic rocks. We suggest that the studied mafic rocks likely represent the basement of an initial island arc, which was generated in a supra-subduction zone setting within the Neotethys branch of the Sabzevar Ocean at the north of CIM. Copper, gold and chromite mineralizations are studied in relation to island arc setting and supra-subduction environment. Similarities in lithology, ophiolite age and mineralization between Sabzevar ophiolite and Bardaskan-Torbat Heydariyeh ophiolites testify for their separation due to rotation (or faulting) of the Central Iranian Micro-continent. KW - Supra-subduction zone KW - Ophiolite KW - Island arc KW - Mineralization KW - Neotethys KW - Iran Y1 - 2017 U6 - https://doi.org/10.1007/s00710-017-0505-3 SN - 0930-0708 SN - 1438-1168 VL - 112 IS - 1 SP - 65 EP - 83 PB - Springer CY - Wien ER - TY - JOUR A1 - Balint, Miklos A1 - Marton, Orsolya A1 - Schatz, Marlene A1 - Düring, Rolf-Alexander A1 - Grossart, Hans-Peter T1 - Proper experimental design requires randomization/balancing of molecular ecology experiments JF - Ecology and evolution N2 - Properly designed (randomized and/or balanced) experiments are standard in ecological research. Molecular methods are increasingly used in ecology, but studies generally do not report the detailed design of sample processing in the laboratory. This may strongly influence the interpretability of results if the laboratory procedures do not account for the confounding effects of unexpected laboratory events. We demonstrate this with a simple experiment where unexpected differences in laboratory processing of samples would have biased results if randomization in DNA extraction and PCR steps do not provide safeguards. We emphasize the need for proper experimental design and reporting of the laboratory phase of molecular ecology research to ensure the reliability and interpretability of results. KW - batch effect KW - bias KW - DNA extraction KW - environmental DNA KW - laboratory practice KW - lake community KW - metabarcoding KW - nondemonic intrusions KW - PCR KW - sediment Y1 - 2018 U6 - https://doi.org/10.1002/ece3.3687 SN - 2045-7758 VL - 8 IS - 3 SP - 1786 EP - 1793 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Bukowski, Alexandra R. A1 - Schittko, Conrad A1 - Petermann, Jana S. T1 - The strength of negative plant-soil feedback increases from the intraspecific to the interspecific and the functional group level JF - Ecology and evolution N2 - One of the processes that may play a key role in plant species coexistence and ecosystem functioning is plant-soil feedback, the effect of plants on associated soil communities and the resulting feedback on plant performance. Plant-soil feedback at the interspecific level (comparing growth on own soil with growth on soil from different species) has been studied extensively, while plant-soil feedback at the intraspecific level (comparing growth on own soil with growth on soil from different accessions within a species) has only recently gained attention. Very few studies have investigated the direction and strength of feedback among different taxonomic levels, and initial results have been inconclusive, discussing phylogeny, and morphology as possible determinants. To test our hypotheses that the strength of negative feedback on plant performance increases with increasing taxonomic level and that this relationship is explained by morphological similarities, we conducted a greenhouse experiment using species assigned to three taxonomic levels (intraspecific, interspecific, and functional group level). We measured certain fitness-related aboveground traits and used them along literature-derived traits to determine the influence of morphological similarities on the strength and direction of the feedback. We found that the average strength of negative feedback increased from the intraspecific over the interspecific to the functional group level. However, individual accessions and species differed in the direction and strength of the feedback. None of our results could be explained by morphological dissimilarities or individual traits. Synthesis. Our results indicate that negative plant-soil feedback is stronger if the involved plants belong to more distantly related species. We conclude that the taxonomic level is an important factor in the maintenance of plant coexistence with plant-soil feedback as a potential stabilizing mechanism and should be addressed explicitly in coexistence research, while the traits considered here seem to play a minor role. KW - Arabidopsis thaliana Col-0 KW - home-away effect KW - intraspecific diversity KW - morphological similarities KW - dissimilarities of plants KW - plant-soil (belowground) interactions KW - species coexistence KW - taxonomic levels KW - trait measurements Y1 - 2018 U6 - https://doi.org/10.1002/ece3.3755 SN - 2045-7758 VL - 8 IS - 4 SP - 2280 EP - 2289 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Martins, Renata F. A1 - Schmidt, Anke A1 - Lenz, Dorina A1 - Wilting, Andreas A1 - Fickel, Jörns T1 - Historical biogeography of Rusa unicolor and R-timorensis BT - Historical biogeography of Rusa unicolor and R. timorensis JF - Ecology and evolution N2 - In this study we compared the phylogeographic patterns of two Rusa species, Rusa unicolor and Rusa timorensis, in order to understand what drove and maintained differentiation between these two geographically and genetically close species and investigated the route of introduction of individuals to the islands outside of the Sunda Shelf. We analyzed full mitogenomes from 56 archival samples from the distribution areas of the two species and 18 microsatellite loci in a subset of 16 individuals to generate the phylogeographic patterns of both species. Bayesian inference with fossil calibration was used to estimate the age of each species and major divergence events. Our results indicated that the split between the two species took place during the Pleistocene, similar to 1.8Mya, possibly driven by adaptations of R. timorensis to the drier climate found on Java compared to the other islands of Sundaland. Although both markers identified two well-differentiated clades, there was a largely discrepant pattern between mitochondrial and nuclear markers. While nDNA separated the individuals into the two species, largely in agreement with their museum label, mtDNA revealed that all R. timorensis sampled to the east of the Sunda shelf carried haplotypes from R. unicolor and one Rusa unicolor from South Sumatra carried a R. timorensis haplotype. Our results show that hybridization occurred between these two sister species in Sundaland during the Late Pleistocene and resulted in human-mediated introduction of hybrid descendants in all islands outside Sundaland. KW - Cervidae KW - human introduction KW - hybridization KW - Phylogeography KW - Sundaland Y1 - 2017 U6 - https://doi.org/10.1002/ece3.3754 SN - 2045-7758 VL - 8 IS - 3 SP - 1465 EP - 1479 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Tomaszewska, Paulina A1 - Krahe, Barbara T1 - Predictors of sexual aggression victimization and perpetration among Polish University Students BT - a Longitudinal Study JF - Archives of sexual behavior : the official publication of the International Academy of Sex Research N2 - This two-wave study investigated predictors of sexual aggression victimization and perpetration in a convenience sample of 318 Polish university students (214 women), considering males and females from the perspective of both victims and perpetrators. At T1, we assessed participants’ risky sexual scripts (defined as cognitive representations of consensual sexual interactions containing elements related to sexual aggression), risky sexual behavior, pornography use, religiosity, sexual self-esteem, and attitudes toward sexual coercion. These variables were used to predict sexual aggression perpetration and victimization reports obtained 12 months later (T2) for two time windows: (a) since the age of 15 until a year ago and (b) in the past year. As expected, risky sexual scripts were linked to risky sexual behavior and indirectly increased the likelihood of victimization in both time windows. Lower sexual self-esteem predicted sexual victimization since age 15, but not in the past 12 months. Pornography use and religiosity indirectly predicted victimization via risky scripts and behavior. Attitudes toward sexual coercion were a prospective predictor of sexual aggression perpetration. The results extend the international literature on sexual aggression and have implications for sexual education and sexual aggression prevention programs. KW - Youth sexual aggression KW - Sexual scripts KW - Pornography KW - Religiosity KW - Poland Y1 - 2016 U6 - https://doi.org/10.1007/s10508-016-0823-2 SN - 0004-0002 SN - 1573-2800 VL - 47 IS - 2 SP - 493 EP - 505 PB - Springer CY - New York ER - TY - JOUR A1 - Hoehnel, Desirée A1 - Reimold, Wolf Uwe A1 - Altenberger, Uwe A1 - Hofmann, Axel A1 - Mohr-Westheide, Tanja A1 - Oezdemir, Seda A1 - Köberl, Christian T1 - Petrographic and Micro-XRF analysis of multiple archean impact-derived spherule layers in drill core CT3 from the northern Barberton Greenstone Belt (South Africa) JF - Journal of African earth sciences / Geological Society of Africa N2 - The Archean spherule layers (SLs) of the Barberton Greenstone Belt (BGB, South Africa) and Pilbara Craton (Australia) are the only known evidence of early, large impact events on Earth. Spherules in these layers have been, alternatively, interpreted as molten impact ejecta, condensation products from an impact vapor cloud, or ejecta from impact craters melted during atmospheric re-entry. Recently, a new exploration drill core (CT3) from the northern BGB revealed 17 SL intersections. Spherules are densely packed, sand-sized, and variably rounded or deformed. The CT3 SLs are intercalated with black and brown shale, and laminated chert. The determination of the original number of impact events that are represented by these multiple SLs is central to the present paper. A comprehensive study of the sedimentary and petrographic characteristics of these SLs involved the determination of the size, shape and types of individual spherules, as well as their mineralogy. CT3 SLs consist of K-feldspar, phyllosilicate, siderite, dolomite, quartz, Ti- and Fe-oxides, as well as apatite. In addition, small amounts of carbonaceous, presumably organic material are observed in several spherules at 145 and 149 m depth. Only Ni-rich Cr-spinel (up to 11 wt% NiO) crystals, rare zircon grains, and alloys of platinum group elements ± Fe or Ni represent primary phases in these thoroughly altered strata. The 0.3 to 2.6-mm-sized spherules can be classified into four types: 1. Spherules crystallized completely with secondary K-feldspar (subtype 1A) or phyllosilicate (subtype 1B); spherules completely filled with Ti- and Fe-oxides (subtype 1C); spherules containing disordered or radially oriented, fibrous and lath-shaped K-feldspar textures (subtype 1D); or subtype 1B spherules that contain significant Cr-spinel (subtype 1E); 2. zoned compositions with these types 1A and/or 1B minerals (subtype 2A); spherules that contain central or marginal vesicles (subtype 2B); subtype 1B spherules whose rims consist of Ti and Fe-oxides (subtype 2C); 3. deformed spherules (subtype 3A) - of all types; (B) subtype 1B spherules are assimilated into groundmass; (C) open spherules or spherules with collapsed rims; and 4. interconnected spherules of type 1A. A few spherules show botryoidal devitrification textures interpreted to result from rapid cooling/devitrification of former melt droplets. SL 15 at a depth of 145 m is unique in being the only grain-size sorted SL; this bed may have been deposited by fallout through a water column. The SL and their host rocks can be easily distinguished by their significant differences in micro-XRF elemental distribution maps. Depending on which aspects of the SLs are primarily considered (such as similar geochemistry, similar layering, SL occurrences abundant at three different depth intervals), the 17 CT3 SLs can be assigned to three or up to 13 individual impact events. Uncertainty about the actual number of impact events represented remains, however, due to the complex folding deformation observed throughout the drill core. KW - Archean spherule layers KW - Barberton Greenstone Belt KW - Petrography KW - Micro-XRF KW - Record of multiple impacts Y1 - 2017 U6 - https://doi.org/10.1016/j.jafrearsci.2017.11.020 SN - 1464-343X SN - 1879-1956 VL - 138 SP - 264 EP - 288 PB - Elsevier Science CY - Oxford ER - TY - JOUR A1 - Weng, Wei A1 - Lüdeke, Matthias K. B. A1 - Zemp, Delphine Clara A1 - Lakes, Tobia A1 - Kropp, Jürgen T1 - Aerial and surface rivers BT - downwind impacts on water availability from land use changes in Amazonia JF - Hydrology and earth system sciences : HESS N2 - The abundant evapotranspiration provided by the Amazon forests is an important component of the hydrological cycle, both regionally and globally. Since the last century, deforestation and expanding agricultural activities have been changing the ecosystem and its provision of moisture to the atmosphere. However, it remains uncertain how the ongoing land use change will influence rainfall, runoff, and water availability as findings from previous studies differ. Using moisture tracking experiments based on observational data, we provide a spatially detailed analysis recognizing potential teleconnection between source and sink regions of atmospheric moisture. We apply land use scenarios in upwind moisture sources and quantify the corresponding rainfall and runoff changes in downwind moisture sinks. We find spatially varying responses of water regimes to land use changes, which may explain the diverse results from previous studies. Parts of the Peruvian Amazon and western Bolivia are identified as the sink areas most sensitive to land use change in the Amazon and we highlight the current water stress by Amazonian land use change on these areas in terms of the water availability. Furthermore, we also identify the influential source areas where land use change may considerably reduce a given target sink's water reception (from our example of the Ucayali River basin outlet, rainfall by 5–12 % and runoff by 19–50 % according to scenarios). Sensitive sinks and influential sources are therefore suggested as hotspots for achieving sustainable land–water management. Y1 - 2018 U6 - https://doi.org/10.5194/hess-22-911-2018 SN - 1027-5606 SN - 1607-7938 VL - 22 IS - 1 SP - 911 EP - 927 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Ramiaramanantsoa, Tahina A1 - Moffat, Anthony F. J. A1 - Harmon, Robert A1 - Ignace, R. A1 - St-Louis, Nicole A1 - Vanbeveren, Dany A1 - Shenar, Tomer A1 - Pablo, Herbert A1 - Richardson, Noel D. A1 - Howarth, Ian D. A1 - Stevens, Ian R. A1 - Piaulet, Caroline A1 - St-Jean, Lucas A1 - Eversberg, Thomas A1 - Pigulski, Andrzej A1 - Popowicz, Adam A1 - Kuschnig, Rainer A1 - Zoclonska, Elzbieta A1 - Buysschaert, Bram A1 - Handler, Gerald A1 - Weiss, Werner W. A1 - Wade, Gregg A. A1 - Rucinski, Slavek M. A1 - Zwintz, Konstanze A1 - Luckas, Paul A1 - Heathcote, Bernard A1 - Cacella, Paulo A1 - Powles, Jonathan A1 - Locke, Malcolm A1 - Bohlsen, Terry A1 - Chené, André-Nicolas A1 - Miszalski, Brent A1 - Waldron, Wayne L. A1 - Kotze, Marissa M. A1 - Kotze, Enrico J. A1 - Böhm, Torsten T1 - BRITE-Constellation high-precision time-dependent photometry of the early O-type supergiant zeta Puppis unveils the photospheric drivers of its small- and large-scale wind structures JF - Monthly notices of the Royal Astronomical Society N2 - From 5.5 months of dual-band optical photometric monitoring at the 1 mmag level, BRITE-Constellation has revealed two simultaneous types of variability in the O4I(n)fp star ζ Puppis: one single periodic non-sinusoidal component superimposed on a stochastic component. The monoperiodic component is the 1.78-d signal previously detected by Coriolis/Solar Mass Ejection Imager, but this time along with a prominent first harmonic. The shape of this signal changes over time, a behaviour that is incompatible with stellar oscillations but consistent with rotational modulation arising from evolving bright surface inhomogeneities. By means of a constrained non-linear light-curve inversion algorithm, we mapped the locations of the bright surface spots and traced their evolution. Our simultaneous ground-based multisite spectroscopic monitoring of the star unveiled cyclical modulation of its He ii λ4686 wind emission line with the 1.78-d rotation period, showing signatures of corotating interaction regions that turn out to be driven by the bright photospheric spots observed by BRITE. Traces of wind clumps are also observed in the He ii λ4686 line and are correlated with the amplitudes of the stochastic component of the light variations probed by BRITE at the photosphere, suggesting that the BRITE observations additionally unveiled the photospheric drivers of wind clumps in ζ Pup and that the clumping phenomenon starts at the very base of the wind. The origins of both the bright surface inhomogeneities and the stochastic light variations remain unknown, but a subsurface convective zone might play an important role in the generation of these two types of photospheric variability. KW - techniques: photometric KW - techniques: spectroscopic KW - stars: massive KW - stars: rotation KW - starspots KW - supergiants KW - stars: winds, outflows Y1 - 2017 U6 - https://doi.org/10.1093/mnras/stx2671 SN - 0035-8711 SN - 1365-2966 VL - 473 IS - 4 SP - 5532 EP - 5569 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Wachs, Sebastian A1 - Whittle, Helen C. A1 - Hamilton-Giachritsis, Catherine A1 - Wolf, Karsten D. A1 - Vazsonyi, Alexander T. A1 - Junger, Marianne T1 - Correlates of Mono- and Dual-Victims of Cybergrooming and Cyberbullying BT - Evidence from Four Countries JF - Cyberpsychology, behavior and social networking N2 - Today's adolescents grow up using information and communication technologies as an integral part of their everyday life. This affords them with extensive opportunities, but also exposes them to online risks, such as cybergrooming and cyberbullying victimization. The aims of this study were to investigate correlates of cybergrooming and cyberbullying victimization and examine whether victims of both cybergrooming and cyberbullying (dual-cybervictims) show higher involvement in compulsive Internet use (CIU) and troubled offline behavior (TOB) compared to victims of either cybergrooming or cyberbullying (mono-cybervictims). The sample consisted of 2,042 Dutch, German, Thai, and U.S. adolescents (age = 11–17 years; M = 14.2; SD = 1.4). About every ninth adolescent (10.9 percent) reported either mono- or dual-cybervictimization. Second, both CIU and TOB were associated with all three types of cybervictimization, and finally, both CIU and TOB were more strongly linked to dual-cybervictimization than to both forms of mono-cybervictimization. These findings contribute to a better understanding of the associations between different forms of cybervictimization and psychological health and behavior problems among adolescents. KW - cybergrooming KW - cyberbullying KW - cybervictimization KW - adolescents KW - compulsive Internet use KW - troubled offline behavior Y1 - 2018 U6 - https://doi.org/10.1089/cyber.2016.0733 SN - 2152-2715 SN - 2152-2723 VL - 21 IS - 2 SP - 91 EP - 98 PB - Liebert CY - New Rochelle ER - TY - JOUR A1 - Ohm, Stefan A1 - Hoischen, Clemens T1 - On the expected gamma-ray emission from nearby flaring stars JF - Monthly notices of the Royal Astronomical Society N2 - Stellar flares have been extensively studied in soft X-rays (SXRs) by basically every X-ray mission. Hard X-ray (HXR) emission from stellar superflares, however, have only been detected from a handful of objects over the past years. One very extreme event was the superflare from the young M-dwarf DGCVn binary star system, which triggered Swift/BAT as if it was a gamma-ray burst. In this work, we estimate the expected gamma-ray emission from DGCVn and the most extreme stellar flares by extrapolating from solar flares based on measured solar energetic particles (SEPs), as well as thermal and non-thermal emission properties. We find that ions are plausibly accelerated in stellar superflares to 100 GeV energies, and possibly up to TeV energies in the associated coronal mass ejections. The corresponding pi(0)-decay gamma-ray emission could be detectable from stellar superflares with ground-based gamma-ray telescopes. On the other hand, the detection of gamma-ray emission implies particle densities high enough that ions suffer significant losses due to inelastic proton-proton scattering. The next-generation Cherenkov Telescope Array (CTA) should be able to probe superflares from M dwarfs in the solar neighbourhood and constrain the energy in interacting cosmic rays and/or their maximum energy. The detection of gamma-ray emission from stellar flares would open a new window for the study of stellar physics, the underlying physical processes in flares and their impact on habitability of planetary systems. KW - radiation mechanisms: non-thermal KW - stars: flare KW - stars: individual: DGCVn-gamma rays: stars Y1 - 2018 U6 - https://doi.org/10.1093/mnras/stx2806 SN - 0035-8711 SN - 1365-2966 VL - 474 IS - 1 SP - 1335 EP - 1341 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Wieser, Matthias J. A1 - Hambach, Anna A1 - Weymar, Mathias T1 - Neurophysiological correlates of attentional bias for emotional faces in socially anxious individuals BT - Evidence from a visual search task and N2pc JF - Biological psychology N2 - Visual search paradigms have provided evidence for the enhanced capture of attention by threatening faces. Especially in social anxiety, hypervigilance for threatening faces has been found repeatedly across behavioral paradigms, whose reliability however have been questioned recently. In this EEG study, we sought to determine whether the detection of threat (angry faces) is specifically enhanced in individuals with high (HSA) compared to low social anxiety (LSA). In a visual search paradigm, the N2pc component of the event-related brain potential was measured as an electrophysiological indicator of attentional selection. Twenty-one HSA and twenty-one LSA participants were investigated while searching for threatening or friendly targets within an array of neutral faces, or neutral targets within threatening or friendly distractors. Whereas no differences were found in reaction times, HSA showed significant higher detection rates for angry faces, whereas LSA showed a clear ‘happiness bias’. HSA also showed enhanced N2pc amplitudes in response to emotional facial expressions (angry and happy), indicating a general attentional bias for emotional faces. Overall, the results show that social anxiety may be characterized not only by a spatial attentional bias for threatening faces, but for emotional faces in general. In addition, the results further demonstrate the utility of the N2pc component in capturing subtle attentional biases. KW - N2pc KW - EEG KW - Social anxiety KW - Facial expression KW - Threat Y1 - 2018 U6 - https://doi.org/10.1016/j.biopsycho.2018.01.004 SN - 0301-0511 SN - 1873-6246 VL - 132 SP - 192 EP - 201 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Käch, Heidi A1 - Mathe-Hubert, Hugo A1 - Dennis, Alice B. A1 - Vorburger, Christoph T1 - Rapid evolution of symbiont-mediated resistance compromises biological control of aphids by parasitoids JF - Evolutionary applications N2 - There is growing interest in biological control as a sustainable and environmentally friendly way to control pest insects. Aphids are among the most detrimental agricultural pests worldwide, and parasitoid wasps are frequently employed for their control. The use of asexual parasitoids may improve the effectiveness of biological control because only females kill hosts and because asexual populations have a higher growth rate than sexuals. However, asexuals may have a reduced capacity to track evolutionary change in their host populations. We used a factorial experiment to compare the ability of sexual and asexual populations of the parasitoid Lysiphlebus fabarum to control caged populations of black bean aphids (Aphis fabae) of high and low clonal diversity. The aphids came from a natural population, and one-third of the aphid clones harbored Hamiltonella defensa, a heritable bacterial endosymbiont that increases resistance to parasitoids. We followed aphid and parasitoid population dynamics for 3months but found no evidence that the reproductive mode of parasitoids affected their effectiveness as biocontrol agents, independent of host clonal diversity. Parasitoids failed to control aphids in most cases, because their introduction resulted in strong selection for clones protected by H.defensa. The increasingly resistant aphid populations escaped control by parasitoids, and we even observed parasitoid extinctions in many cages. The rapid evolution of symbiont-conferred resistance in turn imposed selection on parasitoids. In cages where asexual parasitoids persisted until the end of the experiment, they became dominated by a single genotype able to overcome the protection provided by H.defensa. Thus, there was evidence for parasitoid counteradaptation, but it was generally too slow for parasitoids to regain control over aphid populations. It appears that when pest aphids possess defensive symbionts, the presence of parasitoid genotypes able to overcome symbiont-conferred resistance is more important for biocontrol success than their reproductive mode. KW - aphids KW - Aphis fabae KW - biological control KW - defensive symbiosis KW - Hamiltonella defensa KW - Lysiphlebus fabarum KW - parasitoid KW - resistance Y1 - 2018 U6 - https://doi.org/10.1111/eva.12532 SN - 1752-4571 VL - 11 IS - 2 SP - 220 EP - 230 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Hesse, Julia A1 - Klier, Dennis Tobias A1 - Sgarzi, Massimo A1 - Nsubuga, Anne A1 - Bauer, Christoph A1 - Grenzer, Joerg A1 - Hübner, Rene A1 - Wislicenus, Marcus A1 - Joshi, Tanmaya A1 - Kumke, Michael Uwe A1 - Stephan, Holger T1 - Rapid Synthesis of Sub-10nm Hexagonal NaYF4-Based Upconverting Nanoparticles using Therminol((R))66 JF - ChemistryOpen : including thesis treasury N2 - We report a simple one-pot method for the rapid preparation of sub-10nm pure hexagonal (-phase) NaYF4-based upconverting nanoparticles (UCNPs). Using Therminol((R))66 as a co-solvent, monodisperse UCNPs could be obtained in unusually short reaction times. By varying the reaction time and reaction temperature, it was possible to control precisely the particle size and crystalline phase of the UCNPs. The upconversion (UC) luminescence properties of the nanocrystals were tuned by varying the concentrations of the dopants (Nd3+ and Yb3+ sensitizer ions and Er3+ activator ions). The size and phase-purity of the as-synthesized core and core-shell nanocrystals were assessed by using complementary transmission electron microscopy, dynamic light scattering, X-ray diffraction, and small-angle X-ray scattering studies. In-depth photophysical evaluation of the UCNPs was pursued by using steady-state and time-resolved luminescence spectroscopy. An enhancement in the UC intensity was observed if the nanocrystals, doped with optimized concentrations of lanthanide sensitizer/activator ions, were further coated with an inert/active shell. This was attributed to the suppression of surface-related luminescence quenching effects. KW - core-shell materials KW - lanthanides KW - nanostructures KW - photoluminescence KW - upconversion Y1 - 2018 U6 - https://doi.org/10.1002/open.201700186 SN - 2191-1363 VL - 7 IS - 2 SP - 159 EP - 168 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Nagel, Rebecca A1 - Kirschbaum, Frank A1 - Engelmann, Jacob A1 - Hofmann, Volker A1 - Pawelzik, Felix A1 - Tiedemann, Ralph T1 - Male-mediated species recognition among African weakly electric fishes JF - Royal Society Open Science N2 - Effective communication among sympatric species is often instrumental for behavioural isolation, where the failure to successfully discriminate between potential mates could lead to less fit hybrid offspring. Discrimination between con- and heterospecifics tends to occur more often in the sex that invests more in offspring production, i.e. females, but males may also mediate reproductive isolation. In this study, we show that among two Campylomormyrus Africanweakly electric fish species, males preferentially associate with conspecific females during choice tests using live fish as stimuli, i.e. when all sensory modalities potentially used for communication were present. We then conducted playback experiments to determine whether the species-specific electric organ discharge (EOD) used for electrocommunication serves as the cue for this conspecific association preference. Interestingly, only C. compressirostris males associated significantly more with the conspecific EOD waveform when playback stimuli were provided, while no such association preference was observed in C. tamandua males. Given our results, the EOD appears to serve, in part, as a male-mediated pre-zygotic isolation mechanism among sympatric species. However, the failure of C. tamandua males to discriminate between con- and heterospecific playback discharges suggests that multiple modalities may be necessary for species recognition in some African weakly electric fish species. KW - Campylomormyrus KW - communication KW - electric fishes KW - pre-zygotic isolation KW - species recognition Y1 - 2018 U6 - https://doi.org/10.1098/rsos.170443 SN - 2054-5703 VL - 5 IS - 2 PB - Royal Society CY - London ER - TY - JOUR A1 - Heger, Tina A1 - Nikles, Gabriele A1 - Jacobs, Brooke S. T1 - Differentiation in native as well as introduced ranges BT - germination reflects mean and variance in cover of surrounding vegetation JF - AoB PLANTS N2 - Germination, a crucial phase in the life cycle of a plant, can be significantly influenced by competition and facilitation. The aim of this study was to test whether differences in cover of surrounding vegetation can lead to population differentiation in germination behaviour of an annual grassland species, and if so, whether such a differentiation can be found in the native as well as in the introduced range. We used maternal progeny of Erodium cicutarium previously propagated under uniform conditions that had been collected in multiple populations in the native and two introduced ranges, in populations representing extremes in terms of mean and variability of the cover of surrounding vegetation. In the first experiment, we tested the effect of germination temperature and mean cover at the source site on germination, and found interlinked effects of these factors. In seeds from one of the introduced ranges (California), we found indication for a 2-fold dormancy, hindering germination at high temperatures even if physical dormancy was broken and water was available. This behaviour was less strong in high cover populations, indicating cross-generational facilitating effects of dense vegetation. In the second experiment, we tested whether spatial variation in cover of surrounding vegetation has an effect on the proportion of dormant seeds. Contrary to our expectations, we found that across source regions, high variance in cover was associated with higher proportions of seeds germinating directly after storage. In all three regions, germination seemed to match the local environment in terms of climate and vegetation cover. We suggest that this is due to a combined effect of introduction of preadapted genotypes and local evolutionary processes. KW - Bet-hedging KW - competition KW - eco-evolutionary experience KW - facilitation KW - genetic adaptation KW - physical and physiological dormancy KW - preadaptation Y1 - 2018 U6 - https://doi.org/10.1093/aobpla/ply009 SN - 2041-2851 VL - 10 IS - 1 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Müller, Sandra Marie A1 - Ebert, Franziska A1 - Raber, Georg A1 - Meyer, Sören A1 - Bornhorst, Julia A1 - Hüwel, Stephan A1 - Galla, Hans-Joachim A1 - Francesconi, Kevin A. A1 - Schwerdtle, Tanja T1 - Effects of arsenolipids on in vitro blood-brain barrier model JF - Archives of toxicology : official journal of EUROTOX N2 - Arsenic-containing hydrocarbons (AsHCs), a subgroup of arsenolipids (AsLs) occurring in fish and edible algae, possess a substantial neurotoxic potential in fully differentiated human brain cells. Previous in vivo studies indicating that AsHCs cross the blood–brain barrier of the fruit fly Drosophila melanogaster raised the question whether AsLs could also cross the vertebrate blood–brain barrier (BBB). In the present study, we investigated the impact of several representatives of AsLs (AsHC 332, AsHC 360, AsHC 444, and two arsenic-containing fatty acids, AsFA 362 and AsFA 388) as well as of their metabolites (thio/oxo-dimethylpropionic acid, dimethylarsinic acid) on porcine brain capillary endothelial cells (PBCECs, in vitro model for the blood–brain barrier). AsHCs exerted the strongest cytotoxic effects of all investigated arsenicals as they were up to fivefold more potent than the toxic reference species arsenite (iAsIII). In our in vitro BBB-model, we observed a slight transfer of AsHC 332 across the BBB after 6 h at concentrations that do not affect the barrier integrity. Furthermore, incubation with AsHCs for 72 h led to a disruption of the barrier at sub-cytotoxic concentrations. The subsequent immunocytochemical staining of three tight junction proteins revealed a significant impact on the cell membrane. Because AsHCs enhance the permeability of the in vitro blood–brain barrier, a similar behavior in an in vivo system cannot be excluded. Consequently, AsHCs might facilitate the transfer of accompanying foodborne toxicants into the brain. KW - Arsenolipids KW - Arsenic-containing hydrocarbons KW - Arsenic-containing fatty acids KW - In vitro blood-brain barrier model Y1 - 2017 SN - 0340-5761 SN - 1432-0738 VL - 92 IS - 2 SP - 823 EP - 832 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Knöchel, Jane A1 - Kloft, Charlotte A1 - Huisinga, Wilhelm T1 - Understanding and reducing complex systems pharmacology models based on a novel input-response index JF - Journal of pharmacokinetics and pharmacodynamics N2 - A growing understanding of complex processes in biology has led to large-scale mechanistic models of pharmacologically relevant processes. These models are increasingly used to study the response of the system to a given input or stimulus, e.g., after drug administration. Understanding the input–response relationship, however, is often a challenging task due to the complexity of the interactions between its constituents as well as the size of the models. An approach that quantifies the importance of the different constituents for a given input–output relationship and allows to reduce the dynamics to its essential features is therefore highly desirable. In this article, we present a novel state- and time-dependent quantity called the input–response index that quantifies the importance of state variables for a given input–response relationship at a particular time. It is based on the concept of time-bounded controllability and observability, and defined with respect to a reference dynamics. In application to the brown snake venom–fibrinogen (Fg) network, the input–response indices give insight into the coordinated action of specific coagulation factors and about those factors that contribute only little to the response. We demonstrate how the indices can be used to reduce large-scale models in a two-step procedure: (i) elimination of states whose dynamics have only minor impact on the input–response relationship, and (ii) proper lumping of the remaining (lower order) model. In application to the brown snake venom–fibrinogen network, this resulted in a reduction from 62 to 8 state variables in the first step, and a further reduction to 5 state variables in the second step. We further illustrate that the sequence, in which a recursive algorithm eliminates and/or lumps state variables, has an impact on the final reduced model. The input–response indices are particularly suited to determine an informed sequence, since they are based on the dynamics of the original system. In summary, the novel measure of importance provides a powerful tool for analysing the complex dynamics of large-scale systems and a means for very efficient model order reduction of nonlinear systems. KW - Control theory KW - Model order reduction KW - Blood coagulation network KW - Nonlinear systems Y1 - 2017 U6 - https://doi.org/10.1007/s10928-017-9561-x SN - 1567-567X SN - 1573-8744 VL - 45 IS - 1 SP - 139 EP - 157 PB - Springer Science + Business Media B.V. CY - New York ER - TY - JOUR A1 - Couture, Nicole J. A1 - Irrgang, Anna Maria A1 - Pollard, Wayne A1 - Lantuit, Hugues A1 - Fritz, Michael T1 - Coastal erosion of permafrost soils along the yukon coastal plain and fluxes of organic carbon to the canadian beaufort sea JF - Journal of geophysical research : Biogeosciences N2 - Reducing uncertainties about carbon cycling is important in the Arctic where rapid environmental changes contribute to enhanced mobilization of carbon. Here we quantify soil organic carbon (SOC) contents of permafrost soils along the Yukon Coastal Plain and determine the annual fluxes from coastal erosion. Different terrain units were assessed based on surficial geology, morphology, and ground ice conditions. To account for the volume of wedge ice and massive ice in a unit, SOC contents were reduced by 19% and sediment contents by 16%. The SOC content in a 1m(2) column of soil varied according to the height of the bluff, ranging from 30 to 662kg, with a mean value of 183kg. Forty-four per cent of the SOC was within the top 1m of soil and values varied based on surficial materials, ranging from 30 to 53kg C/m(3), with a mean of 41kg. Eighty per cent of the shoreline was erosive with a mean annual rate of change of -0.7m/yr. This resulted in a SOC flux per meter of shoreline of 132kg C/m/yr, and a total flux for the entire 282km of the Yukon coast of 35.5 x 10(6) kg C/yr (0.036 Tg C/yr). The mean flux of sediment per meter of shoreline was 5.3 x 10(3) kg/m/yr, with a total flux of 1,832 x 10(6)kg/yr (1.832 Tg/yr). Sedimentation rates indicate that approximately 13% of the eroded carbon was sequestered in nearshore sediments, where the overwhelming majority of organic carbon was of terrestrial origin. Plain Language Summary The oceans help slow the buildup of carbon dioxide (CO2) because they absorb much of this greenhouse gas. However, if carbon from other sources is added to the oceans, it can affect their ability to absorb atmospheric CO2. Our study examines the organic carbon added to the Canadian Beaufort Sea from eroding permafrost along the Yukon coast, a region quite vulnerable to erosion. Understanding carbon cycling in this area is important because environmental changes in the Arctic such as longer open water seasons, rising sea levels, and warmer air, water and soil temperatures are likely to increase coastal erosion and, thus, carbon fluxes to the sea. We measured the carbon in different types of permafrost soils and applied corrections to account for the volume taken up by various types of ground ice. By determining how quickly the shoreline is eroding, we assessed how much organic carbon is being transferred to the ocean each year. Our results show that 36 x 10(6) kg of carbon is added annually from this section of the coast. If we extrapolate these results to other coastal areas along the Canadian Beaufort Sea, the flux of organic carbon is nearly 3 times what was previously thought. KW - coastal erosion KW - organic carbon KW - ground ice KW - Yukon KW - Canadian Beaufort Sea Y1 - 2018 U6 - https://doi.org/10.1002/2017JG004166 SN - 2169-8953 SN - 2169-8961 VL - 123 IS - 2 SP - 406 EP - 422 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Meessen, Christian A1 - Sippel, Judith A1 - Scheck-Wenderoth, Magdalena A1 - Heine, C. A1 - Strecker, Manfred T1 - Crustal structure of the andean foreland in Northern Argentina BT - results from data-integrative three-dimensional density modeling JF - Journal of geophysical research : Solid earth N2 - Previous thermomechanical modeling studies indicated that variations in the temperature and strength of the crystalline crust might be responsible for the juxtaposition of domains with thin-skinned and thick-skinned crustal deformation along strike the foreland of the central Andes. However, there is no evidence supporting this hypothesis from data-integrative models. We aim to derive the density structure of the lithosphere by means of integrated 3-D density modeling, in order to provide a new basis for discussions of compositional variations within the crust and for future thermal and rheological modeling studies. Therefore, we utilize available geological and geophysical data to obtain a structural and density model of the uppermost 200km of the Earth. The derived model is consistent with the observed Bouguer gravity field. Our results indicate that the crystalline crust in northern Argentina can be represented by a lighter upper crust (2,800kg/m(3)) and a denser lower crust (3,100kg/m(3)). We find new evidence for high bulk crustal densities >3,000kg/m(3) in the northern Pampia terrane. These could originate from subducted Puncoviscana wackes or pelites that ponded to the base of the crystalline crust in the late Proterozoic or indicate increasing bulk content of mafic material. The precise composition of the northern foreland crust, whether mafic or felsic, has significant implications for further thermomechanical models and the rheological behavior of the lithosphere. A detailed sensitivity analysis of the input parameters indicates that the model results are robust with respect to the given uncertainties of the input data. KW - central Andean foreland KW - gravity modeling KW - crustal density structure Y1 - 2018 U6 - https://doi.org/10.1002/2017JB014296 SN - 2169-9313 SN - 2169-9356 VL - 123 IS - 2 SP - 1875 EP - 1903 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Kotha, Sreeram Reddy A1 - Bazzurro, Paolo A1 - Pagani, Marco T1 - Effects of epistemic uncertainty in seismic hazard estimates on building portfolio losses JF - Earthquake spectra : the professional journal of the Earthquake Engineering Research Institute N2 - In catastrophe risk modeling, a defensible estimation of impact severity and its likelihood of occurrence to a portfolio of assets can only be made through a rigorous treatment of uncertainty and the consideration of multiple alternative models. This approach, however, requires repeating lengthy calculations multiple times. To limit the demand on computational time and resources, a frequent practice in the industry is to estimate the distribution of earthquake-induced portfolio losses using a simulated catalog of events from a single representative mean ground motion hazard model for the region. This simplified approach is faster but may provide biased estimates of the likelihood of occurrence of the large and infrequent losses that drive many risk mitigation decisions. Investigation through case studies of different portfolios of assets located in the San Francisco Bay Region shows the potential for both a bias in the mean loss estimates and an underestimation of their central 70% interpercentile. We propose a simplified and computationally practical approach that reduces the bias in the mean portfolio loss estimates. This approach does not improve the estimate of the interpercentile range, however, a quantity of no direct practical use. Y1 - 2018 U6 - https://doi.org/10.1193/020515EQS020M SN - 8755-2930 SN - 1944-8201 VL - 34 IS - 1 SP - 217 EP - 236 PB - Earthquake Engineering Research Institute CY - Oakland ER - TY - JOUR A1 - Yaouba, Souaibou A1 - Koch, Andreas A1 - Guantai, Eric M. A1 - Derese, Solomon A1 - Irungu, Beatrice A1 - Heydenreich, Matthias A1 - Yenesew, Abiy T1 - Alkenyl cyclohexanone derivatives from Lannea rivae and Lannea schweinfurthii JF - Phytochemistry letters / Phytochemical Society of Europe N2 - Phytochemical investigation of the CH2Cl2/MeOH (1:1) extract of the roots of Lannea rivae (Chiov) Sacleux (Anacardiaceae) led to the isolation of a new alkenyl cyclohexenone derivative: (4R,6S)-4,6-dihydroxy-6-((Z)-nonadec-14′-en-1-yl)cyclohex-2-en-1-one (1), and a new alkenyl cyclohexanol derivative: (2S*,4R*,5S*)-2,4,5-trihydroxy-2-((Z)-nonadec-14′-en-1-yl)cyclohexanone (2) along with four known compounds, namely epicatechin gallate, taraxerol, taraxerone and β-sitosterol; while the stem bark afforded two known compounds, daucosterol and lupeol. Similar investigation of the roots of Lannea schweinfurthii (Engl.) Engl. led to the isolation of four known compounds: 3-((E)-nonadec-16′-enyl)phenol, 1-((E)-heptadec-14′-enyl)cyclohex-4-ene-1,3-diol, catechin, and 1-((E)-pentadec-12′-enyl)cyclohex-4-ene-1,3-diol. The structures of the isolated compounds were determined by NMR spectroscopy and mass spectrometry. The absolute configuration of compound 1 was established by quantum chemical ECD calculations. In an antibacterial activity assay using the microbroth kinetic method, compound 1 showed moderate activity against Escherichia coli while compound 2 exhibited moderate activity against Staphylococcus aureus. Compound 1 also showed moderate activity against E. coli using the disc diffusion method. The roots extract of L. rivae was notably cytotoxic against both the DU-145 prostate cancer cell line and the Vero mammalian cell line (CC50 = 5.24 and 5.20 μg/mL, respectively). Compound 1 was also strongly cytotoxic against the DU-145 cell line (CC50 = 0.55 μg/mL) but showed no observable cytotoxicity (CC50 > 100 μg/mL) against the Vero cell line. The roots extract of L. rivae and L. schweinfurthii, epicatechin gallate as well as compound 1 exhibited inhibition of carageenan-induced inflammation. KW - Lannea rivae KW - Lannea schweinfurthii KW - Alkenyl cyclohexenone KW - Alkenyl cyclohexanone KW - Anti-inflammatory KW - Cytotoxicity KW - Antimicrobial Y1 - 2017 U6 - https://doi.org/10.1016/j.phytol.2017.12.001 SN - 1874-3900 SN - 1876-7486 VL - 23 SP - 141 EP - 148 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Zhou, Yuefang A1 - Fischer, Martin H. T1 - Mimicking non-verbal emotional expressions and empathy development in simulated consultations BT - an experimental feasibility study JF - Patient education and counseling N2 - Objective: To explore the feasibility of applying an experimental design to study the relationship between non-verbal emotions and empathy development in simulated consultations. Method: In video-recorded simulated consultations, twenty clinicians were randomly allocated to either an experimental group (instructed to mimic non-verbal emotions of a simulated patient, SP) or a control group (no such instruction). Baseline empathy scores were obtained before consultation, relational empathy was rated by SP after consultation. Multilevel logistic regression modelled the probability of mimicry occurrence, controlling for baseline empathy and clinical experience. ANCOVA compared group differences on relational empathy and consultation smoothness. Results: Instructed mimicry lasted longer than spontaneous mimicry. Mimicry was marginally related to improved relational empathy. SP felt being treated more like a whole person during consultations with spontaneous mimicry. Clinicians who displayed spontaneous mimicry felt consultations went more smoothly. Conclusion: The experimental approach improved our understanding of how non-verbal emotional mimicry contributed to relational empathy development during consultations. Further work should ascertain the potential of instructed mimicry to enhance empathy development. Practice implications: Understanding how non-verbal emotional mimicry impacts on patients’ perceived clinician empathy during consultations may inform training and intervention programme development. KW - Mimicry KW - Non-verbal emotion KW - Empathy KW - Experimental design Y1 - 2017 U6 - https://doi.org/10.1016/j.pec.2017.08.016 SN - 0738-3991 VL - 101 IS - 2 SP - 304 EP - 309 PB - Elsevier Science CY - Clare ER - TY - JOUR A1 - Bustamante Duarte, Ana Maria A1 - Brendel, Nina A1 - Degbelo, Auriol A1 - Kray, Christian T1 - Participatory design and participatory research BT - an HCI case study with young forced migrants JF - ACM transactions on computer human interaction : TOCHI / Association for Computing Machinery N2 - Participatory design (PD) in HCI has been successfully applied to vulnerable groups, but further research is still needed on forced migrants. We report on a month-long case study with a group of about 25 young forced migrants (YFMs), where we applied and adapted strategies from PD and participatory research (PR). We gained insights into the benefits and drawbacks of combining PD and PR concepts in this particular scenario. The PD+PR approach supported intercultural collaborations between YFMs and young members of the host community. It also enabled communication across language barriers by using visual and “didactic reduction” resources. On a theoretical level, the experiences we gained allowed us to reflect on the role of “safe spaces” for participation and the need for further discussing it in PD. Our results can benefit researchers who take part in technology-related participatory processes with YFMs. KW - Vulnerable communities KW - forced migrants KW - participatory research Y1 - 2018 U6 - https://doi.org/10.1145/3145472 SN - 1073-0516 SN - 1557-7325 VL - 25 IS - 1 SP - 1 EP - 39 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Göritz, Anna A1 - Berger, Stella A. A1 - Gege, Peter A1 - Grossart, Hans-Peter A1 - Nejstgaard, Jens C. A1 - Riedel, Sebastian A1 - Röttgers, Rüdiger A1 - Utschig, Christian T1 - Retrieval of water constituents from hyperspectral in-situ measurements under variable cloud cover BT - a case study at Lake Stechlin (Germany) JF - Remote sensing / Molecular Diversity Preservation International (MDPI) N2 - Remote sensing and field spectroscopy of natural waters is typically performed under clear skies, low wind speeds and low solar zenith angles. Such measurements can also be made, in principle, under clouds and mixed skies using airborne or in-situ measurements; however, variable illumination conditions pose a challenge to data analysis. In the present case study, we evaluated the inversion of hyperspectral in-situ measurements for water constituent retrieval acquired under variable cloud cover. First, we studied the retrieval of Chlorophyll-a (Chl-a) concentration and colored dissolved organic matter (CDOM) absorption from in-water irradiance measurements. Then, we evaluated the errors in the retrievals of the concentration of total suspended matter (TSM), Chl-a and the absorption coefficient of CDOM from above-water reflectance measurements due to highly variable reflections at the water surface. In order to approximate cloud reflections, we extended a recent three-component surface reflectance model for cloudless atmospheres by a constant offset and compared different surface reflectance correction procedures. Our findings suggest that in-water irradiance measurements may be used for the analysis of absorbing compounds even under highly variable weather conditions. The extended surface reflectance model proved to contribute to the analysis of above-water reflectance measurements with respect to Chl-a and TSM. Results indicate the potential of this approach for all-weather monitoring. KW - remote sensing KW - inland water KW - hyperspectral measurements KW - in-situ KW - cloud KW - surface reflection KW - inversion KW - bio-optical modeling Y1 - 2018 U6 - https://doi.org/10.3390/rs10020181 SN - 2072-4292 VL - 10 IS - 2 PB - MDPI CY - Basel ER - TY - JOUR A1 - Pathiraja, Sahani Darschika A1 - Moradkhani, H. A1 - Marshall, L. A1 - Sharma, Ashish A1 - Geenens, G. T1 - Data-driven model uncertainty estimation in hydrologic data assimilation JF - Water resources research : WRR / American Geophysical Union N2 - The increasing availability of earth observations necessitates mathematical methods to optimally combine such data with hydrologic models. Several algorithms exist for such purposes, under the umbrella of data assimilation (DA). However, DA methods are often applied in a suboptimal fashion for complex real-world problems, due largely to several practical implementation issues. One such issue is error characterization, which is known to be critical for a successful assimilation. Mischaracterized errors lead to suboptimal forecasts, and in the worst case, to degraded estimates even compared to the no assimilation case. Model uncertainty characterization has received little attention relative to other aspects of DA science. Traditional methods rely on subjective, ad hoc tuning factors or parametric distribution assumptions that may not always be applicable. We propose a novel data-driven approach (named SDMU) to model uncertainty characterization for DA studies where (1) the system states are partially observed and (2) minimal prior knowledge of the model error processes is available, except that the errors display state dependence. It includes an approach for estimating the uncertainty in hidden model states, with the end goal of improving predictions of observed variables. The SDMU is therefore suited to DA studies where the observed variables are of primary interest. Its efficacy is demonstrated through a synthetic case study with low-dimensional chaotic dynamics and a real hydrologic experiment for one-day-ahead streamflow forecasting. In both experiments, the proposed method leads to substantial improvements in the hidden states and observed system outputs over a standard method involving perturbation with Gaussian noise. KW - data assimilation KW - model error KW - uncertainty quantification KW - particle filter KW - nonparametric statistics Y1 - 2018 U6 - https://doi.org/10.1002/2018WR022627 SN - 0043-1397 SN - 1944-7973 VL - 54 IS - 2 SP - 1252 EP - 1280 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Westphal, Andrea A1 - Kretschmann, Julia A1 - Gronostaj, Anna A1 - Vock, Miriam T1 - More enjoyment, less anxiety and boredom BT - How achievement emotions relate to academic self-concept and teachers' diagnostic skills JF - Learning and individual differences : a multidisciplinary journal in education N2 - Students' achievement emotions are critical in their academic development. Therefore, teachers need to create an emotionally positive learning environment. In the light of this, the present study investigated the connection between students' enjoyment, anxiety, boredom and, in the first case, students' academic self-concept and, in the second, teachers' diagnostic skills. The third part of our study examined whether this link would be moderated by students' academic self-concept. Our sample comprised N = 1803 eighth-grade students who reported their achievement emotions and evaluated the diagnostic skills of both their German and mathematics teachers. Hierarchical models indicated that students experience more enjoyment and less anxiety and boredom if teachers exhibit better diagnostic skills. The role of teachers' diagnostic skills in relation to students' emotions was in part moderated by the students' self-concept. These results are discussed in terms of their implications for effective teaching. KW - Achievement emotions KW - Diagnostic skills KW - Instructional quality KW - Academic self-concept KW - Multilevel modeling Y1 - 2018 U6 - https://doi.org/10.1016/j.lindif.2018.01.016 SN - 1041-6080 SN - 1873-3425 VL - 62 SP - 108 EP - 117 PB - Elsevier B.V. CY - Amsterdam ER - TY - JOUR A1 - Mayor, Jessie A1 - Bora, Sanjay Singh A1 - Cotton, Fabrice T1 - Capturing regional variations of hard‐rock κ0 from coda analysis JF - The bulletin of the Seismological Society of America : BSSA N2 - We propose an alternative procedure for the capture of the hard‐rock regional kappa (⁠κ0ref⁠). In our approach, we make use of a potential link between the well‐known κ parameter and the properties of coda waves. In our analysis, we consider near‐distance records of four crustal earthquakes of local magnitude 3.7–4.9 that occurred in four regions of France in different geological contexts: the crystalline axial chain of Pyrenees to the southwest, the large sedimentary basin to the southeast, the Alpine range to the east, and the extensional Rhine graben to the northeast. Each earthquake has been recorded at a pair of nearby soft‐ and hard‐rock station sites. The high‐frequency (16–32 Hz) spectral amplitudes of the coda window (carefully selected on the time series of the accelerograms) confirm an exponential decrease, which we quantify by κAHcoda and call “kappa of coda.” It is found that κAHcoda is independent of the soil type but shows significant regional variations. κ measurements (Anderson and Hough, 1984) over the coda window (⁠κAHcoda⁠) and full time series (⁠κAH⁠) show strong correlation at hard‐rock sites. This suggests that κAHcoda can provide a new proxy to estimate the regional hard rock κ0ref (Ktenidou et al., 2015). Theoretical analysis is also presented to relate the regional κAHcoda and coda quality factor Qc⁠, which quantifies the average attenuation properties of the crust (both scattering and absorption). It allows interpreting κAHcoda as the time spent by the waves in the medium, weighted by its attenuation properties. This theoretical analysis also shows that the classical κ measurement should be frequency dependent; this was confirmed by the spectra of the observed records. Y1 - 2018 U6 - https://doi.org/10.1785/0120170153 SN - 0037-1106 SN - 1943-3573 VL - 108 IS - 1 SP - 399 EP - 408 PB - Seismological Society of America CY - Albany ER - TY - JOUR A1 - Göbel, Silke M. A1 - McCrink, Koleen A1 - Fischer, Martin H. A1 - Shaki, Samuel T1 - Observation of directional storybook reading influences young children’s counting direction JF - Journal of experimental child psychology N2 - Even before formal schooling, children map numbers onto space in a directional manner. The origin of this preliterate spatial–numerical association is still debated. We investigated the role of enculturation for shaping the directionality of the association between numbers and space, focusing on counting behavior in 3- to 5-year-old preliterate children. Two studies provide evidence that, after observing reading from storybooks (left-to-right or right-to-left reading) children change their counting direction in line with the direction of observed reading. Just observing visuospatial directional movements had no such effect on counting direction. Complementarily, we document that book illustrations, prevalent in children’s cultures, exhibit directionality that conforms to the direction of a culture’s written language. We propose that shared book reading activates spatiotemporal representations of order in young children, which in turn affect their spatial representation of numbers. KW - Counting direction KW - Cross-cultural KW - Mental number line KW - Reading KW - Spatial-numerical association KW - Preschool children Y1 - 2017 U6 - https://doi.org/10.1016/j.jecp.2017.08.001 SN - 0022-0965 SN - 1096-0457 VL - 166 SP - 49 EP - 66 PB - Elsevier CY - New York ER - TY - JOUR A1 - Mendling, Jan A1 - Weber, Ingo A1 - van der Aalst, Wil A1 - Brocke, Jan Vom A1 - Cabanillas, Cristina A1 - Daniel, Florian A1 - Debois, Soren A1 - Di Ciccio, Claudio A1 - Dumas, Marlon A1 - Dustdar, Schahram A1 - Gal, Avigdor A1 - Garcia-Banuelos, Luciano A1 - Governatori, Guido A1 - Hull, Richard A1 - La Rosa, Marcello A1 - Leopold, Henrik A1 - Leymann, Frank A1 - Recker, Jan A1 - Reichert, Manfred A1 - Reijers, Hajo A. A1 - Rinderle-Ma, Stefanie A1 - Solti, Andreas A1 - Rosemann, Michael A1 - Schulte, Stefan A1 - Singh, Munindar P. A1 - Slaats, Tijs A1 - Staples, Mark A1 - Weber, Barbara A1 - Weidlich, Matthias A1 - Weske, Mathias A1 - Xu, Xiwei A1 - Zhu, Liming T1 - Blockchains for Business Process Management BT - Challenges and Opportunities JF - ACM Transactions on Management Information Systems N2 - Blockchain technology offers a sizable promise to rethink the way interorganizational business processes are managed because of its potential to realize execution without a central party serving as a single point of trust (and failure). To stimulate research on this promise and the limits thereof, in this article, we outline the challenges and opportunities of blockchain for business process management (BPM). We first reflect how blockchains could be used in the context of the established BPM lifecycle and second how they might become relevant beyond. We conclude our discourse with a summary of seven research directions for investigating the application of blockchain technology in the context of BPM. KW - Blockchain KW - business process management KW - research challenges Y1 - 2018 U6 - https://doi.org/10.1145/3183367 SN - 2158-656X SN - 2158-6578 VL - 9 IS - 1 SP - 1 EP - 16 PB - Association for Computing Machinery CY - New York ER -