TY - GEN A1 - Azuma, Yusuke A1 - Kükenshöner, Tim A1 - Ma, Guangyong A1 - Yasunaga, Jun-ichiro A1 - Imanishi, Miki A1 - Tanaka, Gen A1 - Nakase, Ikuhiko A1 - Maruno, Takahiro A1 - Kobayashi, Yuji A1 - Arndt, Katja Maren A1 - Matsuoka, Masao A1 - Futaki, Shiroh T1 - Controlling leucine-zipper partner recognition in cells through modification of a–g interactions N2 - By focusing on the a–g interactions, successful design and selection were accomplished to obtain a leucine-zipper segment that discriminates the appropriate partner over another that provides very similar patterns of electrostatic interactions. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 276 Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-98758 ER - TY - GEN A1 - Plehn, Thomas A1 - Megow, Jörg A1 - May, Volkhard T1 - Concerted charge and energy transfer processes in a highly flexible fullerene–dye system BT - a mixed quantum–classical study N2 - Photoinduced excitation energy transfer and accompanying charge separation are elucidated for a supramolecular system of a single fullerene covalently linked to six pyropheophorbide-a dye molecules. Molecular dynamics simulations are performed to gain an atomistic picture of the architecture and the surrounding solvent. Excitation energy transfer among the dye molecules and electron transfer from the excited dyes to the fullerene are described by a mixed quantum–classical version of the Förster rate and the semiclassical Marcus rate, respectively. The mean characteristic time of energy redistribution lies in the range of 10 ps, while electron transfer proceeds within 150 ps. In between, on a 20 to 50 ps time-scale, conformational changes take place in the system. This temporal hierarchy of processes guarantees efficient charge separation, if the structure is exposed to a solvent. The fast energy transfer can adopt the dye excitation to the actual conformation. In this sense, the probability to achieve charge separation is large enough since any dominance of unfavorable conformations that exhibit a large dye–fullerene distance is circumvented. And the slow electron transfer may realize an averaging with respect to different conformations. To confirm the reliability of our computations, ensemble measurements on the charge separation dynamics are simulated and a very good agreement with the experimental data is obtained. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 279 Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-98791 ER - TY - GEN A1 - Schedina, Ina Maria A1 - Hartmann, Stefanie A1 - Groth, Detlef A1 - Schlupp, Ingo A1 - Tiedemann, Ralph T1 - Comparative analysis of the gonadal transcriptomes of the all-female species Poecilia formosa and its maternal ancestor Poecilia mexicana N2 - Background The Amazon molly, Poecilia formosa (Teleostei: Poeciliinae) is an unisexual, all-female species. It evolved through the hybridisation of two closely related sexual species and exhibits clonal reproduction by sperm dependent parthenogenesis (or gynogenesis) where the sperm of a parental species is only used to activate embryogenesis of the apomictic, diploid eggs but does not contribute genetic material to the offspring. Here we provide and describe the first de novo assembled transcriptome of the Amazon molly in comparison with its maternal ancestor, the Atlantic molly Poecilia mexicana. The transcriptome data were produced through sequencing of single end libraries (100 bp) with the Illumina sequencing technique. Results 83,504,382 reads for the Amazon molly and 81,625,840 for the Atlantic molly were assembled into 127,283 and 78,961 contigs for the Amazon molly and the Atlantic molly, respectively. 63% resp. 57% of the contigs could be annotated with gene ontology terms after sequence similarity comparisons. Furthermore, we were able to identify genes normally involved in reproduction and especially in meiosis also in the transcriptome dataset of the apomictic reproducing Amazon molly. Conclusions We assembled and annotated the transcriptome of a non-model organism, the Amazon molly, without a reference genome (de novo). The obtained dataset is a fundamental resource for future research in functional and expression analysis. Also, the presence of 30 meiosis-specific genes within a species where no meiosis is known to take place is remarkable and raises new questions for future research. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 404 Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-401420 ER - TY - GEN A1 - Kaiser, Eurika A1 - Noack, Bernd R. A1 - Cordier, Laurent A1 - Spohn, Andreas A1 - Segond, Marc A1 - Abel, Markus A1 - Daviller, Guillaume A1 - Osth, Jan A1 - Krajnovic, Sinisa A1 - Niven, Robert K. T1 - Cluster-based reduced-order modelling of a mixing layer T2 - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe N2 - We propose a novel cluster-based reduced-order modelling (CROM) strategy for unsteady flows. CROM combines the cluster analysis pioneered in Gunzburger's group (Burkardt, Gunzburger & Lee, Comput. Meth. Appl. Mech. Engng, vol. 196, 2006a, pp. 337-355) and transition matrix models introduced in fluid dynamics in Eckhardt's group (Schneider, Eckhardt & Vollmer, Phys. Rev. E, vol. 75, 2007, art. 066313). CROM constitutes a potential alternative to POD models and generalises the Ulam-Galerkin method classically used in dynamical systems to determine a finite-rank approximation of the Perron-Frobenius operator. The proposed strategy processes a time-resolved sequence of flow snapshots in two steps. First, the snapshot data are clustered into a small number of representative states, called centroids, in the state space. These centroids partition the state space in complementary non-overlapping regions (centroidal Voronoi cells). Departing from the standard algorithm, the probabilities of the clusters are determined, and the states are sorted by analysis of the transition matrix. Second, the transitions between the states are dynamically modelled using a Markov process. Physical mechanisms are then distilled by a refined analysis of the Markov process, e. g. using finite-time Lyapunov exponent (FTLE) and entropic methods. This CROM framework is applied to the Lorenz attractor (as illustrative example), to velocity fields of the spatially evolving incompressible mixing layer and the three-dimensional turbulent wake of a bluff body. For these examples, CROM is shown to identify non-trivial quasi-attractors and transition processes in an unsupervised manner. CROM has numerous potential applications for the systematic identification of physical mechanisms of complex dynamics, for comparison of flow evolution models, for the identification of precursors to desirable and undesirable events, and for flow control applications exploiting nonlinear actuation dynamics. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 605 KW - low-dimensional models KW - nonlinear dynamical systems KW - shear layers Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-416113 SN - 1866-8372 IS - 605 SP - 365 EP - 414 ER - TY - GEN A1 - Hoos, Holger A1 - Lindauer, Marius A1 - Schaub, Torsten T1 - claspfolio 2 BT - advances in algorithm selection for answer set programming T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Building on the award-winning, portfolio-based ASP solver claspfolio, we present claspfolio 2, a modular and open solver architecture that integrates several different portfolio-based algorithm selection approaches and techniques. The claspfolio 2 solver framework supports various feature generators, solver selection approaches, solver portfolios, as well as solver-schedule-based pre-solving techniques. The default configuration of claspfolio 2 relies on a light-weight version of the ASP solver clasp to generate static and dynamic instance features. The flexible open design of claspfolio 2 is a distinguishing factor even beyond ASP. As such, it provides a unique framework for comparing and combining existing portfolio-based algorithm selection approaches and techniques in a single, unified framework. Taking advantage of this, we conducted an extensive experimental study to assess the impact of different feature sets, selection approaches and base solver portfolios. In addition to gaining substantial insights into the utility of the various approaches and techniques, we identified a default configuration of claspfolio 2 that achieves substantial performance gains not only over clasp's default configuration and the earlier version of claspfolio, but also over manually tuned configurations of clasp. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 606 KW - solver KW - sat Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-416129 SN - 1866-8372 IS - 606 ER - TY - GEN A1 - Liu, W. A1 - Tkachov, R. A1 - Komber, H. A1 - Senkovskyy, V. A1 - Schubert, M. A1 - Wei, Z. A1 - Facchetti, A. A1 - Neher, Dieter A1 - Kiriy, A. T1 - Chain-growth polycondensation of perylene diimide-based copolymers BT - a new route to regio-regular perylene diimide-based acceptors for all-polymer solar cells and n-type transistors N2 - Herein, we report the chain-growth tin-free room temperature polymerization method to synthesize n-type perylene diimide-dithiophene-based conjugated polymers (PPDIT2s) suitable for solar cell and transistor applications. The palladium/electron-rich tri-tert-butylphosphine catalyst is effective to enable the chain-growth polymerization of anion-radical monomer Br-TPDIT-Br/Zn to PPDIT2 with a molecular weight up to Mw ≈ 50 kg mol−1 and moderate polydispersity. This is the second example of the polymerization of unusual anion-radical aromatic complexes formed in a reaction of active Zn and electron-deficient diimide-based aryl halides. As such, the discovered polymerization method is not a specific reactivity feature of the naphthalene-diimide derivatives but is rather a general polymerization tool. This is an important finding, given the significantly higher maximum external quantum efficiency that can be reached with PDI-based copolymers (32–45%) in all-polymer solar cells compared to NDI-based materials (15–30%). Our studies revealed that PPDIT2 synthesized by the new method and the previously published polymer prepared by step-growth Stille polycondensation show similar electron mobility and all-polymer solar cell performance. At the same time, the polymerization reported herein has several technological advantages as it proceeds relatively fast at room temperature and does not involve toxic tin-based compounds. Because several chain-growth polymerization reactions are well-suited for the preparation of well-defined multi-functional polymer architectures, the next target is to explore the utility of the discovered polymerization in the synthesis of end-functionalized polymers and block copolymers. Such materials would be helpful to improve the nanoscale morphology of polymer blends in all-polymer solar cells. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 273 Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-98724 ER - TY - GEN A1 - Bechi, Beatrice A1 - Herter, Susanne A1 - McKenna, Shane A1 - Riley, Christopher A1 - Leimkühler, Silke A1 - Turner, Nicholas J. A1 - Carnell, Andrew J. T1 - Catalytic bio–chemo and bio–bio tandem oxidation reactions for amide and carboxylic acid synthesis N2 - A catalytic toolbox for three different water-based one-pot cascades to convert aryl alcohols to amides and acids and cyclic amines to lactams, involving combination of oxidative enzymes (monoamine oxidase, xanthine dehydrogenase, galactose oxidase and laccase) and chemical oxidants (TBHP or CuI(cat)/H2O2) at mild temperatures, is presented. Mutually compatible conditions were found to afford products in good to excellent yields. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 282 Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-99414 ER - TY - GEN A1 - Ehlert, Christopher A1 - Unger, Wolfgang E. S. A1 - Saalfrank, Peter T1 - C K-edge NEXAFS spectra of graphene with physical and chemical defects BT - a study based on density functional theory N2 - Recently, C K-edge Near Edge X-ray Absorption Fine Structure (NEXAFS) spectra of graphite (HOPG) surfaces have been measured for the pristine material, and for HOPG treated with either bromine or krypton plasmas (Lippitz et al., Surf. Sci., 2013, 611, L1). Changes of the NEXAFS spectra characteristic for physical (krypton) and/or chemical/physical modifications of the surface (bromine) upon plasma treatment were observed. Their molecular origin, however, remained elusive. In this work we study by density functional theory, the effects of selected point and line defects as well as chemical modifications on NEXAFS carbon K-edge spectra of single graphene layers. For Br-treated surfaces, also Br 3d X-ray Photoelectron Spectra (XPS) are simulated by a cluster approach, to identify possible chemical modifications. We observe that some of the defects related to plasma treatment lead to characteristic changes of NEXAFS spectra, similar to those in experiment. Theory provides possible microscopic origins for these changes. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 173 KW - absorbtion fine-structure KW - graphite Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-74429 SP - 14083 EP - 14095 ER - TY - GEN A1 - Kronauer, Jörg T1 - Beziehungen am Scheideweg? : Die NSA-Affäre und das deutschamerikanische Verhältnis N2 - Enthüllungen über groß angelegte NSA-Lauschangriffe auf die Bundesrepublik, die auch vor dem Mobiltelefon der Bundeskanzlerin nicht haltmachten, haben mit neuer Intensität nicht nur die Frage nach dem deutsch-amerikanischen Verhältnis auf die Tagesordnung gesetzt. Bedeutet diese Massenspionage, dass Grundrechte in Deutschland von auswärtigen Diensten umstandslos außer Kraft gesetzt werden können? Oder ist sie der Vorbote eines aufziehenden Hegemonialkonflikts zwischen der EU und den USA? KW - Hegemonie KW - USA KW - Geheimdienste Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-71845 ER - TY - GEN A1 - Germano, Gustavo T1 - Ausências Brasil N2 - Von der Militärdiktatur ermordet und spurlos verschwunden – diese Ausstellung greift zurück auf Fotoalben der Familienangehörigen von Brasilianern, die der systematischen Repression, Folter und Verschleppung der brasilianischen Militärdiktatur (1964–1985) zum Opfer gefallen sind: Arbeiter, Stadtguerilleros, Studenten, Akademiker, ganze Familien. KW - Militärdiktatur KW - Brasilien KW - Südamerika Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-71139 ER - TY - GEN A1 - Klaucke, Daniel T1 - Auf Wüste gebaut und heilig : Israel und das Westjordanland N2 - Vor allem leer. Und doch ist der Negev gespickt mit Siedlungen und Städten. Etwa 800.000 Menschen leben hier von Landwirtschaft, Schwerindustrie, Tourismus und Militär. Wie vor Jahrtausenden siedeln dort Beduinen. Netanjahus Regierung will 40.000 von ihnen umsiedeln. Das führte im Dezember 2013 zum „Tag des Zorns“ von Beduinen, Arabern und Palästinensern. KW - Israel KW - Westjordanland KW - Naher Osten Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-71837 ER - TY - GEN A1 - Meyer, Sören A1 - Schulz, Jacqueline A1 - Jeibmann, Astrid A1 - Taleshi, Mojtaba S. A1 - Ebert, Franziska A1 - Francesconi, Kevin A1 - Schwerdtle, Tanja T1 - Arsenic-containing hydrocarbons are toxic in the in vivo model Drosophila melanogaster N2 - Arsenic-containing hydrocarbons (AsHC) constitute one group of arsenolipids that have been identified in seafood. In this first in vivo toxicity study for AsHCs, we show that AsHCs exert toxic effects in Drosophila melanogaster in a concentration range similar to that of arsenite. In contrast to arsenite, however, AsHCs cause developmental toxicity in the late developmental stages of Drosophila melanogaster. This work illustrates the need for a full characterisation of the toxicity of AsHCs in experimental animals to finally assess the risk to human health related to the presence of arsenolipids in seafood. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 183 KW - cod-liver KW - arsenolipids present KW - fatty-acids KW - rp-hplc KW - identification KW - fish KW - oil Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-76819 VL - 11 IS - 6 SP - 2010 EP - 2014 ER - TY - GEN A1 - Metzler, Ralf A1 - Jeon, Jae-Hyung A1 - Cherstvy, Andrey G. A1 - Barkai, Eli T1 - Anomalous diffusion models and their properties BT - non-stationarity, non-ergodicity, and ageing at the centenary of single particle tracking N2 - Modern microscopic techniques following the stochastic motion of labelled tracer particles have uncovered significant deviations from the laws of Brownian motion in a variety of animate and inanimate systems. Such anomalous diffusion can have different physical origins, which can be identified from careful data analysis. In particular, single particle tracking provides the entire trajectory of the traced particle, which allows one to evaluate different observables to quantify the dynamics of the system under observation. We here provide an extensive overview over different popular anomalous diffusion models and their properties. We pay special attention to their ergodic properties, highlighting the fact that in several of these models the long time averaged mean squared displacement shows a distinct disparity to the regular, ensemble averaged mean squared displacement. In these cases, data obtained from time averages cannot be interpreted by the standard theoretical results for the ensemble averages. Here we therefore provide a comparison of the main properties of the time averaged mean squared displacement and its statistical behaviour in terms of the scatter of the amplitudes between the time averages obtained from different trajectories. We especially demonstrate how anomalous dynamics may be identified for systems, which, on first sight, appear to be Brownian. Moreover, we discuss the ergodicity breaking parameters for the different anomalous stochastic processes and showcase the physical origins for the various behaviours. This Perspective is intended as a guidebook for both experimentalists and theorists working on systems, which exhibit anomalous diffusion. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 174 KW - Fokker-Planck equations KW - flight search patterns KW - fluctuation-dissipation theorem KW - fluorescence photobleaching recovery KW - fractional dynamics approach KW - intermittent chaotic systems KW - levy flights KW - photon-counting statistics KW - time random-walks KW - weak ergodicity breaking Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-74448 SP - 24128 EP - 24164 ER - TY - GEN A1 - Roder, Phillip A1 - Hille, Carsten T1 - ANG-2 for quantitative Na+ determination in living cells by time-resolved fluorescence microscopy N2 - Sodium ions (Na+) play an important role in a plethora of cellular processes, which are complex and partly still unexplored. For the investigation of these processes and quantification of intracellular Na+ concentrations ([Na+]i), two-photon coupled fluorescence lifetime imaging microscopy (2P-FLIM) was performed in the salivary glands of the cockroach Periplaneta americana. For this, the novel Na+-sensitive fluorescent dye Asante NaTRIUM Green-2 (ANG-2) was evaluated, both in vitro and in situ. In this context, absorption coefficients, fluorescence quantum yields and 2P action cross-sections were determined for the first time. ANG-2 was 2P-excitable over a broad spectral range and displayed fluorescence in the visible spectral range. Although the fluorescence decay behaviour of ANG-2 was triexponential in vitro, its analysis indicates a Na+-sensitivity appropriate for recordings in living cells. The Na+-sensitivity was reduced in situ, but the biexponential fluorescence decay behaviour could be successfully analysed in terms of quantitative [Na+]i recordings. Thus, physiological 2P-FLIM measurements revealed a dopamine-induced [Na+]i rise in cockroach salivary gland cells, which was dependent on a Na+-K+-2Cl− cotransporter (NKCC) activity. It was concluded that ANG-2 is a promising new sodium indicator applicable for diverse biological systems. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 184 KW - cockroach salivary-glands KW - intracellular na+ KW - sodium green KW - periplaneta-americana KW - ventricular myocytes KW - lifetime microscopy KW - acinar-cells KW - hela-cells KW - rat Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-76851 SP - 1699 EP - 1710 PB - The Royal Society of Chemistry CY - Cambridge ER - TY - GEN A1 - Berner, Elisabeth T1 - Albrecht Greule, Jörg Meier u. Arne Ziegler (Hgg.), Kanzleisprachenforschung. Ein internationales Handbuch / [rezensiert von] Elisabeth Berner N2 - Rezensiertes Werk: Albrecht Greule, Jörg Meier u. Arne Ziegler (Hgg.): Kanzleisprachenforschung. Ein internationales Handbuch. - Berlin u. Boston: de Gruyter 2012 - 680 S. - (XVI) T3 - Zweitveröffentlichungen der Universität Potsdam : Philosophische Reihe - 112 Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-94122 SP - 654 EP - 660 ER - TY - GEN A1 - Kienzler, Sarah A1 - Pech, I. A1 - Kreibich, Heidi A1 - Müller, M. A1 - Thieken, Annegret T1 - After the extreme flood in 2002 BT - changes in preparedness, response and recovery of flood-affected residents in Germany between 2005 and 2011 T2 - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe N2 - In the aftermath of the severe flooding in Central Europe in August 2002, a number of changes in flood policies were launched in Germany and other European countries, aiming at improved risk management. The question arises as to whether these changes have already had an impact on the residents' ability to cope with floods, and whether flood-affected private households are now better prepared than they were in 2002. Therefore, computer-aided telephone interviews with private households in Germany that suffered from property damage due to flooding in 2005, 2006, 2010 or 2011 were performed and analysed with respect to flood awareness, precaution, preparedness and recovery. The data were compared to a similar investigation conducted after the flood in 2002. After the flood in 2002, the level of private precautions taken increased considerably. One contributing factor is the fact that, in general, a larger proportion of people knew that they were at risk of flooding. The best level of precaution was found before the flood events in 2006 and 2011. The main reason for this might be that residents had more experience with flooding than residents affected in 2005 or 2010. Yet, overall, flood experience and knowledge did not necessarily result in building retrofitting or flood-proofing measures, which are considered as mitigating damages most effectively. Hence, investments still need to be stimulated in order to reduce future damage more efficiently. Early warning and emergency responses were substantially influenced by flood characteristics. In contrast to flood-affected people in 2006 or 2011, people affected by flooding in 2005 or 2010 had to deal with shorter lead times and therefore had less time to take emergency measures. Yet, the lower level of emergency measures taken also resulted from the people's lack of flood experience and insufficient knowledge of how to protect themselves. Overall, it was noticeable that these residents suffered from higher losses. Therefore, it is important to further improve early warning systems and communication channels, particularly in hilly areas with rapid-onset flooding. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 488 KW - mitigation behavior KW - private households KW - risk perceptions KW - damage KW - motivation KW - people Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-408056 SN - 1866-8372 IS - 488 SP - 505 EP - 526 ER - TY - GEN A1 - Kazemi, Said Reza T1 - Afghanistan und Zentralasien N2 - In den gegenwärtigen Prozessen in Afghanistan gewinnen die Beziehungen zwischen Afghanistan und seinen Nachbarn in Zentralasien an Bedeutung. Ihre weitere Entwicklung wird einerseits von der Transformation in Afghanistan und andererseits von der Politik der zentralasiatischen Staaten abhängen. Während sich das Drogenproblem erschwerend auswirkt, gibt es einige ermutigende Ansätze im Bereich der wirtschaftlichen Kooperation. KW - Afghanistan KW - Zentralasien KW - Wirtschaft KW - Drogenhandel Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-69949 ER - TY - GEN A1 - Weidemann, Diethelm T1 - Afghanistan und die Region N2 - Der Afghanistankonflikt hat seit 2001 deutliche Auswirkungen auf das regionale Umfeld – in Pakistan, Kaschmir, Xinjiang und den zentralasiatischen Republiken. Dies wird sich nach dem Abzug der ISAF-Truppen noch verstärken. Dabei geht es sowohl um die grenzüberschreitenden Folgen der beiden Militärinterventionen als auch um die Wirkungen der innerafghanischen Konflikte auf die gesamte Region. Diese Problematik besitzt ein erhebliches Konfliktpotenzial, das größere Aufmerksamkeit verdient. KW - Zentralasien KW - Afghanistan KW - USA KW - Islamismus Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-69935 ER - TY - GEN A1 - Wirth, Jonas A1 - Neumann, Rainer A1 - Antonietti, Markus A1 - Saalfrank, Peter T1 - Adsorption and photocatalytic splitting of water on graphitic carbon nitride BT - a combined first principles and semiempirical study N2 - Graphitic carbon nitride, g-C₃N₄, is a promising organic photo-catalyst for a variety of redox reactions. In order to improve its efficiency in a systematic manner, however, a fundamental understanding of the microscopic interaction between catalyst, reactants and products is crucial. Here we present a systematic study of water adsorption on g-C₃N₄ by means of density functional theory and the density functional based tight-binding method as a prerequisite for understanding photocatalytic water splitting. We then analyze this prototypical redox reaction on the basis of a thermodynamic model providing an estimate of the overpotential for both water oxidation and H⁺ reduction. While the latter is found to occur readily upon irradiation with visible light, we derive a prohibitive overpotential of 1.56 eV for the water oxidation half reaction, comparing well with the experimental finding that in contrast to H₂ production O₂ evolution is only possible in the presence of oxidation cocatalysts. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 172 KW - augmented-wave method KW - hydrogen KW - initio molecular-dynamics KW - oxidation KW - photooxidation KW - reduction KW - simulations KW - tight-binding KW - transition KW - visible-light Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-74391 SP - 15917 EP - 15926 ER - TY - GEN A1 - Havertz, Ralf T1 - Abe auf Provokationskurs : Japans politisches Spiel mit dem Feuer N2 - Das Land des Lächelns zeigt unter Ministerpräsident Abe zunehmend fratzenhaftere Züge. Japans im negativen Sinne „reizvolle“ Politik irritiert nicht nur seine nächsten Nachbarn China und Korea. Auch die USA sind beunruhigt über das provokante Verhalten ihres Partners im Bündnisfalle. Territorialstreitigkeiten drohen zu eskalieren, die Auseinandersetzung mit der wenig ruhmreichen Vergangenheit wird verweigert. Läuft Japan Gefahr, sämtliche Sympathien zu verspielen? KW - Japan KW - Vergangenheitspolitik KW - Territorialkonflikte Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-71118 ER -