TY - JOUR A1 - Stein, S. A1 - Friedrich, A. M. A1 - Newman, A. T1 - Dependence of possible characteristic earthquakes on spatial sampling: Illustration for the Wasatch seismic zone, Utah Y1 - 2005 SN - 0895-0695 ER - TY - JOUR A1 - Bennett, Richard A. A1 - Friedrich, A. M. A1 - Furlong, K. P. T1 - Codependent histories of the San Andreas and San Jacinto fault zones from inversion of fault displacement rates N2 - The displacement histories of the San Jacinto and southernmost San Andreas fault zones are constrained by offset data with ages in the range of 5 Ma to 5 ka. Apparent discrepancies between long- and short-term average displacement rates can be reconciled with a time-variable rate model. In this model, the displacement rate on the San Andreas decelerated from similar to35 mm/yr at 1.5 Ma to as low as 9 +/- 4 mm/yr by 90 ka. Over this same time period, the rate on the San Jacinto fault zone accelerated from an initial value of zero to a rate of 26 +/- 4 mm/yr. The data also imply that the rate of the San Andreas fault accelerated since ca. 90 ka, from similar to9 mm/yr to the modern rate of 27 +/- 4 mm/yr, whereas the San Jacinto decelerated from 26 +/- 4 mm/yr to the modern rate of 8 +/- 4 mm/yr. The time scale of these changes is significantly longer than the earthquake cycle, but shorter than time scales characteristic of lithospheric-scalle dynamics. The emergence of the San Jacinto fault zone ca. 1.5 Ma coincided with the development of a major restraining bend in the San Andreas fault zone, suggesting that the formation of new subparallell faults could be driven by conditions that inhibit displacement on preexisting faults Y1 - 2004 SN - 0091-7613 ER - TY - JOUR A1 - Kuhnla, A. A1 - Reinthaler, Markus A1 - Braune, Steffen A1 - Maier, A. A1 - Pindur, Gerhard A1 - Lendlein, Andreas A1 - Jung, Friedrich T1 - Spontaneous and induced platelet aggregation in apparently healthy subjects in relation to age JF - Clinical hemorheology and microcirculation : blood flow and vessels N2 - Thrombotic disorders remain the leading cause of mortality and morbidity, despite the fact that anti-platelet therapies and vascular implants are successfully used today. As life expectancy is increasing in western societies, the specific knowledge about processes leading to thrombosis in elderly is essential for an adequate therapeutic management of platelet dysfunction and for tailoring blood contacting implants. This study addresses the limited available data on platelet function in apparently healthy subjects in relation to age, particularly in view of subjects of old age (80-98 years). Apparently healthy subjects between 20 and 98 years were included in this study. Platelet function was assessed by light transmission aggregometry and comprised experiments on spontaneous as well as ristocetin-, ADP- and collagen-induced platelet aggregation. The data of this study revealed a non-linear increase in the maximum spontaneous platelet aggregation (from 3.3% +/- 3.3% to 10.9% +/- 5.9%). The maximum induced aggregation decreased with age for ristocetin (from 85.8% +/- 7.2% to 75.0% +/- 7.8%), ADP (from 88.5% +/- 4.6% to 64.8% +/- 7.3%) and collagen (from 89.5% +/- 3.0% to 64.0% +/- 4.0%) in a non-linear manner (linear regression analysis). These observations indicate that during aging, circulating platelets become increasingly activated but lose their full aggregatory potential, a phenomenon that was earlier termed "platelet exhaustion". In this study we extended the limited existing data for spontaneous and induced platelet aggregation of apparently healthy donors above the age of 75 years. The presented data indicate that the extrapolation of data from a middle age group does not necessarily predict platelet function in apparently healthy subjects of old age. It emphasizes the need for respective studies to improve our understanding of thrombotic processes in elderly humans. Y1 - 2019 U6 - https://doi.org/10.3233/CH-199006 SN - 1386-0291 SN - 1875-8622 VL - 71 IS - 4 SP - 425 EP - 435 PB - IOS Press CY - Amsterdam ER - TY - JOUR A1 - Sangoro, Joshia R. A1 - Iacob, C. A1 - Agapov, A. L. A1 - Wang, Yangyang A1 - Berdzinski, Stefan A1 - Rexhausen, Hans A1 - Strehmel, Veronika A1 - Friedrich, C. A1 - Sokolov, A. P. A1 - Kremer, F. T1 - Decoupling of ionic conductivity from structural dynamics in polymerized ionic liquids JF - Soft matter N2 - Charge transport and structural dynamics in low molecular weight and polymerized 1-vinyl-3-pentylimidazolium bis(trifluoromethylsulfonyl) imide ionic liquids (ILs) are investigated by a combination of broadband dielectric spectroscopy, dynamic mechanical spectroscopy and differential scanning calorimetry. While the dc conductivity and fluidity exhibit practically identical temperature dependence for the non-polymerized IL, a significant decoupling of ionic conduction from structural dynamics is observed for the polymerized IL. In addition, the dc conductivity of the polymerized IL exceeds that of its molecular counterpart by four orders of magnitude at their respective calorimetric glass transition temperatures. This is attributed to the unusually high mobility of the anions especially at lower temperatures when the structural dynamics is significantly slowed down. A simple physical explanation of the possible origin of the remarkable decoupling of ionic conductivity from structural dynamics is proposed. Y1 - 2014 U6 - https://doi.org/10.1039/c3sm53202j SN - 1744-683X SN - 1744-6848 VL - 10 IS - 20 SP - 3536 EP - 3540 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Rienks, Emile D. L. A1 - Wimmer, S. A1 - Sanchez-Barriga, Jaime A1 - Caha, O. A1 - Mandal, Partha Sarathi A1 - Ruzicka, J. A1 - Ney, A. A1 - Steiner, H. A1 - Volobuev, V. V. A1 - Groiss, H. A1 - Albu, M. A1 - Kothleitner, G. A1 - Michalicka, J. A1 - Khan, S. A. A1 - Minar, J. A1 - Ebert, H. A1 - Bauer, G. A1 - Freyse, Friedrich A1 - Varykhalov, Andrei A1 - Rader, Oliver A1 - Springholz, Gunther T1 - Large magnetic gap at the Dirac point in Bi2Te3/MnBi2Te4 heterostructures JF - Nature : the international weekly journal of science N2 - Magnetically doped topological insulators enable the quantum anomalous Hall effect (QAHE), which provides quantized edge states for lossless charge-transport applications(1-8). The edge states are hosted by a magnetic energy gap at the Dirac point(2), but hitherto all attempts to observe this gap directly have been unsuccessful. Observing the gap is considered to be essential to overcoming the limitations of the QAHE, which so far occurs only at temperatures that are one to two orders of magnitude below the ferromagnetic Curie temperature, T-C (ref. (8)). Here we use low-temperature photoelectron spectroscopy to unambiguously reveal the magnetic gap of Mn-doped Bi2Te3, which displays ferromagnetic out-of-plane spin texture and opens up only below T-C. Surprisingly, our analysis reveals large gap sizes at 1 kelvin of up to 90 millielectronvolts, which is five times larger than theoretically predicted(9). Using multiscale analysis we show that this enhancement is due to a remarkable structure modification induced by Mn doping: instead of a disordered impurity system, a self-organized alternating sequence of MnBi2Te4 septuple and Bi2Te3 quintuple layers is formed. This enhances the wavefunction overlap and size of the magnetic gap(10). Mn-doped Bi2Se3 (ref. (11)) and Mn-doped Sb2Te3 form similar heterostructures, but for Bi2Se3 only a nonmagnetic gap is formed and the magnetization is in the surface plane. This is explained by the smaller spin-orbit interaction by comparison with Mn-doped Bi2Te3. Our findings provide insights that will be crucial in pushing lossless transport in topological insulators towards room-temperature applications. Y1 - 2019 U6 - https://doi.org/10.1038/s41586-019-1826-7 SN - 0028-0836 SN - 1476-4687 VL - 576 IS - 7787 SP - 423 EP - 428 PB - Nature Publ. Group CY - London ER - TY - BOOK A1 - Zhang, Shuhao A1 - Plauth, Max A1 - Eberhardt, Felix A1 - Polze, Andreas A1 - Lehmann, Jens A1 - Sejdiu, Gezim A1 - Jabeen, Hajira A1 - Servadei, Lorenzo A1 - Möstl, Christian A1 - Bär, Florian A1 - Netzeband, André A1 - Schmidt, Rainer A1 - Knigge, Marlene A1 - Hecht, Sonja A1 - Prifti, Loina A1 - Krcmar, Helmut A1 - Sapegin, Andrey A1 - Jaeger, David A1 - Cheng, Feng A1 - Meinel, Christoph A1 - Friedrich, Tobias A1 - Rothenberger, Ralf A1 - Sutton, Andrew M. A1 - Sidorova, Julia A. A1 - Lundberg, Lars A1 - Rosander, Oliver A1 - Sköld, Lars A1 - Di Varano, Igor A1 - van der Walt, Estée A1 - Eloff, Jan H. P. A1 - Fabian, Benjamin A1 - Baumann, Annika A1 - Ermakova, Tatiana A1 - Kelkel, Stefan A1 - Choudhary, Yash A1 - Cooray, Thilini A1 - Rodríguez, Jorge A1 - Medina-Pérez, Miguel Angel A1 - Trejo, Luis A. A1 - Barrera-Animas, Ari Yair A1 - Monroy-Borja, Raúl A1 - López-Cuevas, Armando A1 - Ramírez-Márquez, José Emmanuel A1 - Grohmann, Maria A1 - Niederleithinger, Ernst A1 - Podapati, Sasidhar A1 - Schmidt, Christopher A1 - Huegle, Johannes A1 - de Oliveira, Roberto C. L. A1 - Soares, Fábio Mendes A1 - van Hoorn, André A1 - Neumer, Tamas A1 - Willnecker, Felix A1 - Wilhelm, Mathias A1 - Kuster, Bernhard ED - Meinel, Christoph ED - Polze, Andreas ED - Beins, Karsten ED - Strotmann, Rolf ED - Seibold, Ulrich ED - Rödszus, Kurt ED - Müller, Jürgen T1 - HPI Future SOC Lab – Proceedings 2017 T1 - HPI Future SOC Lab – Proceedings 2017 N2 - The “HPI Future SOC Lab” is a cooperation of the Hasso Plattner Institute (HPI) and industry partners. Its mission is to enable and promote exchange and interaction between the research community and the industry partners. The HPI Future SOC Lab provides researchers with free of charge access to a complete infrastructure of state of the art hard and software. This infrastructure includes components, which might be too expensive for an ordinary research environment, such as servers with up to 64 cores and 2 TB main memory. The offerings address researchers particularly from but not limited to the areas of computer science and business information systems. Main areas of research include cloud computing, parallelization, and In-Memory technologies. This technical report presents results of research projects executed in 2017. Selected projects have presented their results on April 25th and November 15th 2017 at the Future SOC Lab Day events. N2 - Das Future SOC Lab am HPI ist eine Kooperation des Hasso-Plattner-Instituts mit verschiedenen Industriepartnern. Seine Aufgabe ist die Ermöglichung und Förderung des Austausches zwischen Forschungsgemeinschaft und Industrie. Am Lab wird interessierten Wissenschaftlern eine Infrastruktur von neuester Hard- und Software kostenfrei für Forschungszwecke zur Verfügung gestellt. Dazu zählen teilweise noch nicht am Markt verfügbare Technologien, die im normalen Hochschulbereich in der Regel nicht zu finanzieren wären, bspw. Server mit bis zu 64 Cores und 2 TB Hauptspeicher. Diese Angebote richten sich insbesondere an Wissenschaftler in den Gebieten Informatik und Wirtschaftsinformatik. Einige der Schwerpunkte sind Cloud Computing, Parallelisierung und In-Memory Technologien. In diesem Technischen Bericht werden die Ergebnisse der Forschungsprojekte des Jahres 2017 vorgestellt. Ausgewählte Projekte stellten ihre Ergebnisse am 25. April und 15. November 2017 im Rahmen der Future SOC Lab Tag Veranstaltungen vor. T3 - Technische Berichte des Hasso-Plattner-Instituts für Digital Engineering an der Universität Potsdam - 130 KW - Future SOC Lab KW - research projects KW - multicore architectures KW - In-Memory technology KW - cloud computing KW - machine learning KW - artifical intelligence KW - Future SOC Lab KW - Forschungsprojekte KW - Multicore Architekturen KW - In-Memory Technologie KW - Cloud Computing KW - maschinelles Lernen KW - Künstliche Intelligenz Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-433100 SN - 978-3-86956-475-3 SN - 1613-5652 SN - 2191-1665 IS - 130 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Hempel, Hannes A1 - Savenjie, Tom J. A1 - Stolterfoht, Martin A1 - Neu, Jens A1 - Failla, Michele A1 - Paingad, Vaisakh C. A1 - Kužel, Petr A1 - Heilweil, Edwin J. A1 - Spies, Jacob A. A1 - Schleuning, Markus A1 - Zhao, Jiashang A1 - Friedrich, Dennis A1 - Schwarzburg, Klaus A1 - Siebbeles, Laurens D. A. A1 - Dörflinger, Patrick A1 - Dyakonov, Vladimir A1 - Katoh, Ryuzi A1 - Hong, Min Ji A1 - Labram, John G. A1 - Monti, Maurizio A1 - Butler-Caddle, Edward A1 - Lloyd-Hughes, James A1 - Taheri, Mohammad M. A1 - Baxter, Jason B. A1 - Magnanelli, Timothy J. A1 - Luo, Simon A1 - Cardon, Joseph M. A1 - Ardo, Shane A1 - Unold, Thomas T1 - Predicting solar cell performance from terahertz and microwave spectroscopy JF - Advanced energy materials N2 - Mobilities and lifetimes of photogenerated charge carriers are core properties of photovoltaic materials and can both be characterized by contactless terahertz or microwave measurements. Here, the expertise from fifteen laboratories is combined to quantitatively model the current-voltage characteristics of a solar cell from such measurements. To this end, the impact of measurement conditions, alternate interpretations, and experimental inter-laboratory variations are discussed using a (Cs,FA,MA)Pb(I,Br)(3) halide perovskite thin-film as a case study. At 1 sun equivalent excitation, neither transport nor recombination is significantly affected by exciton formation or trapping. Terahertz, microwave, and photoluminescence transients for the neat material yield consistent effective lifetimes implying a resistance-free JV-curve with a potential power conversion efficiency of 24.6 %. For grainsizes above approximate to 20 nm, intra-grain charge transport is characterized by terahertz sum mobilities of approximate to 32 cm(2) V-1 s(-1). Drift-diffusion simulations indicate that these intra-grain mobilities can slightly reduce the fill factor of perovskite solar cells to 0.82, in accordance with the best-realized devices in the literature. Beyond perovskites, this work can guide a highly predictive characterization of any emerging semiconductor for photovoltaic or photoelectrochemical energy conversion. A best practice for the interpretation of terahertz and microwave measurements on photovoltaic materials is presented. KW - lifetime KW - microwaves KW - mobility KW - solar cells KW - terahertz Y1 - 2022 U6 - https://doi.org/10.1002/aenm.202102776 SN - 1614-6832 SN - 1614-6840 VL - 12 IS - 13 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Friedrich, A. M. A1 - Lee, J. A1 - Wernicke, B. P. A1 - Sieh, K. T1 - Geologic context of geodetic data across a Basin and Range normal fault, Crescent Valley, Nevada N2 - [1] Geodetic strain and late Quaternary faulting in the Basin and Range province is distributed over a region much wider than historic seismicity, which is localized near the margins of the province. In the relatively aseismic interior, both the magnitude and direction of geodetic strain may be inconsistent with the Holocene faulting record. We document the best example of such a disagreement across the NE striking, similar to55degrees NW dipping Crescent normal fault, where a NW oriented, 70 km geodetic baseline records contemporary shortening of similar to2 mm/yr orthogonal to the fault trace. In contrast, our geomorphic, paleoseismic, and geochronologic analyses of the Crescent fault suggest that a large extensional rupture occurred during the late Holocene epoch. An excavation across the fault at Fourmile Canyon reveals that the most recent event occurred at 2.8 +/- 0.1 ka, with net vertical tectonic displacement of 4.6 +/- 0.4 m at this location, corresponding to the release of similar to3 m of accumulated NW-SE extension. Measured alluvial scarp profiles suggest a minimum rupture length of 30 km along the range front for the event, implying a moment magnitude M-w of at least 6.6. No prior event occurred between similar to2.8 ka and similar to6.4 +/- 0.1 ka, the C-14 calender age of strata near the base of the exposed section. Assuming typical slip rates for Basin and Range faults (similar to0.3 mm/yr), these results imply that up to one third, or similar to1 m, of the extensional strain released in the previous earthquake could have reaccumulated across the fault since similar to2.8 ka. However, the contemporary shortening implies that the fault is unloading due to a transient process, whose duration is limited to between 6 years ( geodetic recording time) and 2.8 ka ( the age of the most recent event). These results emphasize the importance of providing accurate geologic data on the timescale of the earthquake cycle in order to evaluate geodetic measurements Y1 - 2004 SN - 0278-7407 ER - TY - JOUR A1 - Wu, Hao A1 - Han, Yijie A1 - Rodriguez Sillke, Yasmina A1 - Deng, Hongzhang A1 - Siddiqui, Sophiya A1 - Treese, Christoph A1 - Schmidt, Franziska A1 - Friedrich, Marie A1 - Keye, Jacqueline A1 - Wan, Jiajia A1 - Qin, Yue A1 - Kühl, Anja A. A1 - Qin, Zhihai A1 - Siegmund, Britta A1 - Glauben, Rainer T1 - Lipid droplet-dependent fatty acid metabolism controls the immune suppressive phenotype of tumor-associated macrophages JF - EMBO molecular medicine N2 - Tumor-associated macrophages (TAMs) promote tumor growth and metastasis by suppressing tumor immune surveillance. Herein, we provide evidence that the immunosuppressive phenotype of TAMs is controlled by long-chain fatty acid metabolism, specifically unsaturated fatty acids, here exemplified by oleate. Consequently, en-route enriched lipid droplets were identified as essential organelles, which represent effective targets for chemical inhibitors to block in vitro polarization of TAMs and tumor growth in vivo. In line, analysis of human tumors revealed that myeloid cells infiltrating colon cancer but not gastric cancer tissue indeed accumulate lipid droplets. Mechanistically, our data indicate that oleate-induced polarization of myeloid cells depends on the mammalian target of the rapamycin pathway. Thus, our findings reveal an alternative therapeutic strategy by targeting the pro-tumoral myeloid cells on a metabolic level. KW - cancer immunotherapy KW - lipid droplets KW - lipid metabolism KW - tumor microenvironment KW - tumor-associated macrophage Y1 - 2019 U6 - https://doi.org/10.15252/emmm.201910698 SN - 1757-4676 SN - 1757-4684 VL - 11 IS - 11 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Braune, Steffen A1 - Latour, Robert A. A1 - Reinthaler, Markus A1 - Landmesser, Ulf A1 - Lendlein, Andreas A1 - Jung, Friedrich T1 - In Vitro Thrombogenicity Testing of Biomaterials JF - Advanced healthcare materials N2 - The short- and long-term thrombogenicity of implant materials is still unpredictable, which is a significant challenge for the treatment of cardiovascular diseases. A knowledge-based approach for implementing biofunctions in materials requires a detailed understanding of the medical device in the biological system. In particular, the interplay between material and blood components/cells as well as standardized and commonly acknowledged in vitro test methods allowing a reproducible categorization of the material thrombogenicity requires further attention. Here, the status of in vitro thrombogenicity testing methods for biomaterials is reviewed, particularly taking in view the preparation of test materials and references, the selection and characterization of donors and blood samples, the prerequisites for reproducible approaches and applied test systems. Recent joint approaches in finding common standards for a reproducible testing are summarized and perspectives for a more disease oriented in vitro thrombogenicity testing are discussed. KW - biomaterials KW - blood tests KW - implants KW - in vitro KW - thrombogenicity Y1 - 2019 U6 - https://doi.org/10.1002/adhm.201900527 SN - 2192-2640 SN - 2192-2659 VL - 8 IS - 21 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Krüger-Genge, A. A1 - Braune, S. A1 - Walter, M. A1 - Krengel, M. A1 - Kratz, K. A1 - Küpper, J. H. A1 - Lendlein, Andreas A1 - Jung, Friedrich T1 - Influence of different surface treatments of poly(n-butyl acrylate) networks on fibroblasts adhesion, morphology and viability JF - Clinical hemorheology and microcirculation : blood flow and vessels N2 - BACKGROUND: Physical and chemical characteristics of implant materials determine the fate of long-term cardiovascular devices. However, there is still a lack of fundamental understanding of the molecular mechanisms occurring in the material-tissue interphase. In a previous study, soft covalently crosslinked poly(n-butyl acrylate) networks (cPnBA) were introduced as sterilizable, non-toxic and immuno-compatible biomaterials with mechanical properties adjustable to blood vessels. Here we study the influence of different surface treatments in particular oxygen plasma modification and fibrinogen deposition as well as a combinatorial approach on the adhesion and viability of fibroblasts. RESULTS: Compared to non-treated cPnBAs the advancing water-contact angles were found to be reduced after all surface modifications (p<0.05, each), while lowest values were observed after the combined surface treatment (OPT+FIB). The latter differed significantly from the single OPT and FIB. The number of adherent fibroblasts and their adherence behavior differed on both pristine cPnBA networks. The fibroblast density on cPnBA04 was 743 +/- 434 cells. mm(-2), was about 6.5 times higher than on cPnBA73 with 115 +/- 73 cells. mm(-2). On cPnBA04 about 20% of the cells were visible as very small, round and buckled cells while all other cells were in a migrating status. On cPnBA73, nearly 50% of fibroblasts were visible as very small, round and buckled cells. The surface functionalization either using oxygen plasma treatment or fibrinogen coating led to a significant increase of adherent fibroblasts, particularly the combination of both techniques, for both cPnBA networks. It is noteworthy to mention that the fibrinogen coating overruled the characteristics of the pristine surfaces; here, the fibroblast densities after seeding were identical for both cPnBAnetworks. Thus, the binding rather depended on the fibrinogen coating than on the substrate characteristics anymore. While the integrity of the fibroblasts membrane was comparable for both polymers, the MTS tests showed a decreased metabolic activity of the fibroblasts on cPnBA. CONCLUSION: The applied surface treatments of cPnBA successfully improved the adhesion of viable fibroblasts. Under resting conditions as well as after shearing the highest fibroblast densities were found on surfaces with combined post-treatment. KW - Biomaterial KW - poly(n-butyl acrylate) KW - fibroblast KW - oxygen plasma KW - fibrinogen KW - cell adhesion KW - focal adhesion KW - actin cytoskeleton KW - viability Y1 - 2018 U6 - https://doi.org/10.3233/CH-189130 SN - 1386-0291 SN - 1875-8622 VL - 69 IS - 1-2 SP - 305 EP - 316 PB - IOS Press CY - Amsterdam ER - TY - GEN A1 - Blaesius, Thomas A1 - Eube, Jan A1 - Feldtkeller, Thomas A1 - Friedrich, Tobias A1 - Krejca, Martin Stefan A1 - Lagodzinski, Gregor J. A. A1 - Rothenberger, Ralf A1 - Severin, Julius A1 - Sommer, Fabian A1 - Trautmann, Justin T1 - Memory-restricted Routing With Tiled Map Data T2 - 2018 IEEE International Conference on Systems, Man, and Cybernetics (SMC) N2 - Modern routing algorithms reduce query time by depending heavily on preprocessed data. The recently developed Navigation Data Standard (NDS) enforces a separation between algorithms and map data, rendering preprocessing inapplicable. Furthermore, map data is partitioned into tiles with respect to their geographic coordinates. With the limited memory found in portable devices, the number of tiles loaded becomes the major factor for run time. We study routing under these restrictions and present new algorithms as well as empirical evaluations. Our results show that, on average, the most efficient algorithm presented uses more than 20 times fewer tile loads than a normal A*. Y1 - 2018 SN - 978-1-5386-6650-0 U6 - https://doi.org/10.1109/SMC.2018.00567 SN - 1062-922X SP - 3347 EP - 3354 PB - IEEE CY - New York ER - TY - GEN A1 - Rozanski, Stanislaw A. A1 - Kremer, Friedrich A1 - Köberle, Peter A1 - Laschewsky, André T1 - Relaxation and charge transport in mixtures of zwitterionic polymers and inorganic salts N2 - Dielectric spectroscopy is employed to analyze the molecular dynamics and the charge transport in mixtures of zwitterionic polymers of the type poly{3 [N(-methacryloyloxyalkyl)] N, [N-dimethylammonio propanesulfonate] with sodium iodide in the frequency range of 10²Hz-10(up)7 Hz and in the temperature range of 110 K-400 K. The amount of inorganic salt added varies from 0-200 mol-% relative to the number of zwitterionic groups present in the polymer, contributing strongly to the conductivity. One relaxation process is observed whose relaxation rate depends strongly on the length of the aliphatic spacer between the polymethacrylate main chain and the zwitterionic group. Exhibiting an Arrhenius-like temperature depence with activation energy EA = 47 KJ/mol, this relaxation process is assigned to fluctuation of the quaternary ammonium groups in the side chains. At higher temperatures, the dielectric properties and the conductivity are primarily dominated by the mobile inorganic ions: conductivity strongly depends on the salt concentration, showing a pronounced electrode polarization effect. The frequency and salt concentration, dependences of the conductivity can be quantitatively described as hopping of charge carriers being subject to spatially randomly varying energy barriers. For the low-frequency regime and for the critical frequency marking the onset of the conductivity's dispersion, the Barton-Nakajima-Namikawa (BNN) relationship is fulfilled. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 093 Y1 - 1995 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-17438 ER - TY - JOUR A1 - Casel, Katrin A1 - Fischbeck, Philipp A1 - Friedrich, Tobias A1 - Göbel, Andreas A1 - Lagodzinski, J. A. Gregor T1 - Zeros and approximations of Holant polynomials on the complex plane JF - Computational complexity : CC N2 - We present fully polynomial time approximation schemes for a broad class of Holant problems with complex edge weights, which we call Holant polynomials. We transform these problems into partition functions of abstract combinatorial structures known as polymers in statistical physics. Our method involves establishing zero-free regions for the partition functions of polymer models and using the most significant terms of the cluster expansion to approximate them. Results of our technique include new approximation and sampling algorithms for a diverse class of Holant polynomials in the low-temperature regime (i.e. small external field) and approximation algorithms for general Holant problems with small signature weights. Additionally, we give randomised approximation and sampling algorithms with faster running times for more restrictive classes. Finally, we improve the known zero-free regions for a perfect matching polynomial. KW - Holant problems KW - approximate counting KW - partition functions KW - graph KW - polynomials Y1 - 2022 U6 - https://doi.org/10.1007/s00037-022-00226-5 SN - 1016-3328 SN - 1420-8954 VL - 31 IS - 2 PB - Springer CY - Basel ER - TY - JOUR A1 - Friedrich, Jörg F. A1 - Wigant, L. A1 - Unger, Wolfgang E. S. A1 - Lippitz, A. A1 - Wittrich, H. A1 - Prescher, Dietrich A1 - Erdmann, J. A1 - Gorsler, H.-V. A1 - Nick, L. T1 - Barrier properties of plasma-modified polypropylene and polyethylen eterephthalate Y1 - 1995 ER - TY - JOUR A1 - Prescher, Dietrich A1 - Friedrich, Jörg F. A1 - Wigant, L. A1 - Unger, Wolfgang E. S. A1 - Lippitz, A. A1 - Wittrich, H. A1 - Erdmann, J. A1 - Gorsler, H.-V. A1 - Nick, L. T1 - Barrier properties of plasma-modified polypropylene and polyethylenether ephthalate Y1 - 1995 ER - TY - JOUR A1 - Nada, Wael Mohamed Abdel-Rahman A1 - Van Rensburg, L. A1 - Claassens, Sarina A1 - Blumenstein, Oswald A1 - Friedrich, A. T1 - Evaluation of organic matter stability in wood compost by chemical and thermogravimetric analysis JF - International journal of environmental research N2 - This study investigated maturation and stability levels during composting of Quercus robur (QR) woodchips mixed with different nitrogen sources (horse manure, HM and lake mud, LM) for potential agronomic utilisation. The woodchips were mixed with HM and LM, respectively, at mixing ratios of 1QR:2HM or QR:2LM. The experiment was conducted in a greenhouse over 100 days. During composting, organic carbon and its fractioning and humification constituents were quantified. In the final compost product, pH, organic matter (OM), cation exchange capacity (CEC) and selected available nutrients were measured. Thermostability of compost, compared with that of soil and compost mixed with charcoal were also quantified. Results showed OM evolution during the composting process with total organic and extractable carbons and humification indices decreasing, while the degree of humification increased. Compost produced from the 1QR:2HM mix resulted in the highest available nutrients, CEC and OM content values in the final product. Thermogravimetric profiles indicated that compost OM thermostability was higher than that in soil and higher for the 1QR:2HM than the 1QR:2LM mix. Application of charcoal revealed no additional stabilising effect of OM in wood compost. KW - Earthworms KW - Humification KW - Maturity KW - Vermicompost KW - Woodchips Y1 - 2012 SN - 1735-6865 VL - 6 IS - 2 SP - 425 EP - 434 PB - Graduate Faculty of Environment, University of Theran CY - Tehran ER - TY - JOUR A1 - Engeli, Stefan A1 - Lehmann, Anne-Christin A1 - Kaminski, Jana A1 - Haas, Verena A1 - Janke, Urgen A1 - Janke, Jürgen A1 - Zoerner, Alexander A. A1 - Luft, Friedrich C. A1 - Tsikas, Dimitrios A1 - Jordan, Jens T1 - Influence of dietary fat intake on the endocannabinoid system in lean and obese subjects JF - Obesity N2 - Objective: Endocannabinoid system (ECS) activation promotes obesity-associated metabolic disease. Increased dietary fat intake increases blood endocannabinoids and alters adipose and skeletal muscle ECS gene expression in human. Methods: Two weeks isocaloric low- (LFD) and high-fat diets (HFD) in obese (n = 12) and normal- weight (n = 17) subjects in a randomized cross-over study were compared. Blood endocannabinoids were measured in the fasting condition and after food intake using mass spectrometry. Adipose and skeletal muscle gene expression was determined using real-time RT-PCR. Results: Baseline fasting plasma endocannabinoids were similar with both diets. Anandamide decreased similarly with high- or low-fat test meals in both groups. Baseline arachidonoylglycerol plasma concentrations were similar between groups and diets, and unresponsive to eating. In subcutaneous adipose tissue, DAGL-alpha mRNA was upregulated and fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) mRNAs were down-regulated in obese subjects, but the diets had no influence. In contrast, the HFD produced pronounced reductions in skeletal muscle CB1-R and MAGL mRNA expression, whereas obesity did not affect muscular gene expression. Conclusions: Weight-neutral changes in dietary fat intake cannot explain excessive endocannabinoid availability in human obesity. Obesity and dietary fat intake affect ECS gene expression in a tissue-specific manner. Y1 - 2014 U6 - https://doi.org/10.1002/oby.20728 SN - 1930-7381 SN - 1930-739X VL - 22 IS - 5 SP - E70 EP - E76 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Zhuang, Y. A1 - Schelling, Christoph A1 - Stangl, Jochen A1 - Penn, C. A1 - Senz, S. A1 - Schäffler, Friedrich A1 - Roche, T. A1 - Daniel, A. A1 - Grenzer, Jörg A1 - Pietsch, Ullrich A1 - Bauer, Günther T1 - Structural and optical properties of Si/Si{1-x}Ge{x} wires Y1 - 2000 ER - TY - JOUR A1 - Debatin, Franziska A1 - Behrens, Karsten A1 - Weber, Jens A1 - Baburin, Igor A. A1 - Thomas, Arne A1 - Schmidt, Johannes A1 - Senkovska, Irena A1 - Kaskel, Stefan A1 - Kelling, Alexandra A1 - Hedin, Niklas A1 - Bacsik, Zoltan A1 - Leoni, Stefano A1 - Seifert, Gotthard A1 - Jäger, Christian A1 - Günter, Christina A1 - Schilde, Uwe A1 - Friedrich, Alwin A1 - Holdt, Hans-Jürgen T1 - An isoreticular family of microporous metal-organic frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate Syntheses, structures and properties JF - Chemistry - a European journal N2 - We report on a new series of isoreticular frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate (IFP-14, IFP=imidazolate framework Potsdam) that form one-dimensional, microporous hexagonal channels. Varying R in the 2-substitued linker (R=Me (IFP-1), Cl (IFP-2), Br (IFP-3), Et (IFP-4)) allowed the channel diameter (4.01.7 angstrom), the polarisability and functionality of the channel walls to be tuned. Frameworks IFP-2, IFP-3 and IFP-4 are isostructural to previously reported IFP-1. The structures of IFP-2 and IFP-3 were solved by X-ray crystallographic analyses. The structure of IFP-4 was determined by a combination of PXRD and structure modelling and was confirmed by IR spectroscopy and 1H MAS and 13C CP-MAS NMR spectroscopy. All IFPs showed high thermal stability (345400?degrees C); IFP-1 and IFP-4 were stable in boiling water for 7 d. A detailed porosity analysis was performed on the basis of adsorption measurements by using various gases. The potential of the materials to undergo specific interactions with CO2 was investigated by measuring the isosteric heats of adsorption. The capacity to adsorb CH4 (at 298 K), CO2 (at 298 K) and H2 (at 77 K) at high pressure were also investigated. In situ IR spectroscopy showed that CO2 is physisorbed on IFP-14 under dry conditions and that both CO2 and H2O are physisorbed on IFP-1 under moist conditions. KW - adsorption KW - metal- organic frameworks KW - microporous materials KW - N KW - O ligands KW - zinc Y1 - 2012 U6 - https://doi.org/10.1002/chem.201200889 SN - 0947-6539 VL - 18 IS - 37 SP - 11630 EP - 11640 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Kübler, Simon A1 - Streich, R. A1 - Lück, Erika A1 - Hoffmann, M. A1 - Friedrich, A. M. A1 - Strecker, Manfred T1 - Active faulting in a populated low-strain setting (Lower Rhine Graben, Central Europe) identified by geomorphic, geophysical and geological analysis JF - Seismicity, fault rupture and earthquake hazards in slowly deforming regions N2 - The Lower Rhine Graben (Central Europe) is a prime example of a seismically active low-strain rift zone characterized by pronounced anthropogenic and climatic overprint of structures, and long recurrence intervals of large earthquakes. These factors render the identification of active faults and surface ruptures difficult. We investigated two fault scarps in the Lower Rhine Graben, to decipher their structural character, offset and potential seismogenic origin. Both scarps were modified by anthropogenic activity. The Hemmerich site lies c. 20 km SW of Cologne, along the Erft Fault. The Untermaubach site lies SW of Duren, where the Schafberg Fault projects into the Rur River valley. At the Hemmerich site, geomorphic and geophysical data, as well as exploratory coring reveal evidence of repeated normal faulting. Geophysical analysis and palaeoseismological excavation at the Untermaubach site reveal a complex fault zone in Holocene gravels characterized by subtle gravel deformation. Differentiation of tectonic and fluvial features was only possible with trenching, because fault structures and grain sizes of the sediments were below the resolution of the geophysical data. Despite these issues, our investigation demonstrates that valuable insight into past earthquakes and seismogenic deformation in a low-strain environment can be revealed using a multidisciplinary approach. Y1 - 2017 SN - 978-1-86239-745-3 SN - 978-1-86239-964-8 U6 - https://doi.org/10.1144/SP432.11 SN - 0305-8719 VL - 432 SP - 127 EP - 146 PB - The Geological Society CY - London ER - TY - CHAP A1 - Bauer, Hartmut A1 - Markmann, Friedrich A1 - Wichmann, Maren A1 - Becker, Ulrike A1 - Hebeler, Timo A1 - Böttcher, Karl-Ludwig A1 - Glittenberg, Barbara A1 - Kluth, Winfried A1 - Rombey, Wolfgang A1 - Große, Gerrit A1 - Thies, Heike A1 - Pflüger, Georg A. ED - Bauer, Hartmut ED - Büchner, Christiane ED - Markmann, Friedrich T1 - Schulen im kommunalen Bildungsmanagement N2 - Die Schule steckt mitten in einem Umbruch: Dieser wird durch verschiedene Faktoren wie sinkende Schülerzahlen, Zu- und Abwanderungen von Familien mit ihren Kindern, wachsenden Zahlen von Schulpflichtigen mit Migrationshintergrund und anderes mehr gekennzeichnet. Damit steht die Schule vor neuen Herausforderungen. Außerdem hält der Trend zum Gymnasium an. Auch wechselvolle Dauerreformen schaffen unübersichtliche Schulstrukturen und erschweren sichere Orientierung. Und: Im zunehmend raueren Wettbewerb der Schultypen laufen den öffentlichen Schulen immer mehr Schüler davon und zu den Privatschulen über. Schon jetzt sehen sich zahlreiche Kommunen gezwungen, ihre Bildungsangebote zurückzuschrauben und ihre Schulen zu schließen. Kann eine Kommune ihren Bürgern aber nicht mehr die schulische „Grundversorgung“ anbieten, so hat dies weitreichende Folgen. Wo Schulen schließen müssen, „stirbt auch der Ort“. Ein umfangreiches, vielfältiges und flächendeckendes Bildungsangebot dagegen ist für die Kommune tragender Pfeiler einer funktionsfähigen Infrastruktur. Hier setzt die 21. Fachtagung des Kommunalwissenschaftlichen Institutes der Universität Potsdam an. Sie behandelt zentrale Themen der nachhaltigen Gewährleistung schulischer Infrastruktur in den Kommunen einschließlich der dazugehörigen Erfahrungsberichte, die über Best-Practice-Modelle sowie über Erfolgsbedingungen und Fallstricke in der Verwaltungspraxis informieren. Damit gibt die Tagung zugleich Impulse den kommunalen Entscheidungsträgern für die Generierung von und den Umgang mit Gestaltungsoptionen zur Standortsicherung im kommunalen Bildungsmanagement. T3 - KWI-Schriften - 9 Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-74977 SN - 978-3-86956-326-8 SN - 1867-951X SN - 1867-9528 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Blumenstein, Oswald A1 - Bronstert, Axel A1 - Günter, A. A1 - Katzenmeier, D. A1 - Friedrich, Sabine A1 - Geldmacher, Karl A1 - Bork, Rudolf A1 - Röpke, Björn A1 - Schaphoff, Sibyll A1 - Schnur, Tilo A1 - Woithe, Franka A1 - Dalchow, Claus A1 - Faust, Berno A1 - Itzerott, Sibylle A1 - Kaden, Klaus A1 - Knösche, Rüdiger T1 - Umweltforschung für das Land Brandenburg BT - Projekt Schutzgüter Wasser, Boden, Luft JF - Brandenburgische Umwelt-Berichte : BUB ; Schriftenreihe der Mathematisch-Naturwissenschaftlichen Fakultät der Universität Potsdam N2 - BLUMENSTEIN, O.: Investigation of Environmental Quality and Social Structures in a Mining Area in the North West Province of South Africa ; BRONSTERT, A.; GÜNTNER, A.: A large-scale hydrological model for the semi-arid environment of north-eastern Brazil ; BRONSTERT, A. et al.: Hochwasserproblematik und der Zusammenhang mit Landnutzungs- und Klimaänderungen ; FRIEDRICH, S.: Vergleichende Untersuchungen zur Wasserqualität des anfallenden Regenwassers an den 14 Regenwassereinläufen der Stadt Potsdam ; GELDMACHER, K. et al.: Bodenzerstörung im Palouse, Washington, USA ; ITZEROTT, S.; KADEN, K.: Modellierung der flächenhaften Verdunstung im Gebiet der Unteren Havel ; KNÖSCHE, R.: Das remobilisierbare Nährstoffpotential in Augewässersedimenten einer Tieflandflußaue Y1 - 2000 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-3845 SN - 1434-2375 SN - 1611-9339 VL - 8 SP - 136 EP - 173 ER - TY - JOUR A1 - Schleussner, Carl-Friedrich A1 - Donges, Jonathan A1 - Engemann, Denis A. A1 - Levermann, Anders T1 - Clustered marginalization of minorities during social transitions induced by co-evolution of behaviour and network structure JF - Scientific reports N2 - Large-scale transitions in societies are associated with both individual behavioural change and restructuring of the social network. These two factors have often been considered independently, yet recent advances in social network research challenge this view. Here we show that common features of societal marginalization and clustering emerge naturally during transitions in a co-evolutionary adaptive network model. This is achieved by explicitly considering the interplay between individual interaction and a dynamic network structure in behavioural selection. We exemplify this mechanism by simulating how smoking behaviour and the network structure get reconfigured by changing social norms. Our results are consistent with empirical findings: The prevalence of smoking was reduced, remaining smokers were preferentially connected among each other and formed increasingly marginalized clusters. We propose that self-amplifying feedbacks between individual behaviour and dynamic restructuring of the network are main drivers of the transition. This generative mechanism for co-evolution of individual behaviour and social network structure may apply to a wide range of examples beyond smoking. Y1 - 2016 U6 - https://doi.org/10.1038/srep30790 SN - 2045-2322 VL - 6 SP - 3407 EP - 3417 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Wojcinski, Sebastian A1 - Cassel, Michael A1 - Farrokh, Andre A1 - Soliman, Amr A. A1 - Hille, Ursula A1 - Schmidt, Werner A1 - Degenhardt, Friedrich A1 - Hillemanns, Peter T1 - Variations in the elasticity of breast tissue during the menstrual cycle determined by real-time sonoelastography JF - Journal of ultrasound in medicine N2 - Objectives-The purpose of this study was to determine the dependence of breast tissue elasticity on the menstrual cycle of healthy volunteers by means of real-time sonoelastography. Methods-Twenty-two healthy volunteers (aged 18-33 years) were examined once weekly during two consecutive menstrual cycles using sonoelastography. Group 1 (n = 10) was not taking hormonal medication; group 2 (n = 12) was taking oral contraceptives. Results-The breast parenchyma appeared softer than the dermis and harder than the adipose tissue, and elasticity varied over the menstrual cycle and between groups. Group 1 (no hormone intake) showed continuously increasing elasticity with relatively soft breast parenchyma in the menstrual and follicular phases and harder parenchyma in the luteal phase (P = .012). Group 2 (oral contraceptives) showed no statistically significant changes in breast parenchymal elasticity according to sonoelastography. The parenchyma was generally softer in group 1 compared with group 2 throughout the menstrual cycle (P = .033). The dermis, the subcutaneous adipose tissue, and the pectoralis major muscle showed no changes in elasticity. Comparison of measurements made during the first and the second menstrual cycles showed similar patterns of elasticity in both groups. Conclusions-Sonoelastography is a reproducible method that can be used to determine the dependence of breast parenchyma elasticity on the menstrual cycle and on the intake of hormonal contraceptives. KW - breast tissue KW - elasticity imaging KW - real-time tissue elastography KW - sonoelastography Y1 - 2012 SN - 0278-4297 SN - 1550-9613 VL - 31 IS - 1 SP - 63 EP - 72 PB - American Institute of Ultrasound in Medicine CY - Laurel ER - TY - JOUR A1 - Anders, Friedrich A1 - Khalatyan, Arman A1 - Queiroz, Anna B. A. A1 - Chiappini, Cristina A1 - Ardèvol, Judith A1 - Casamiquela, Laia A1 - Figueras, Francesca A1 - Jiménez-Arranz, Óscar A1 - Jordi, Carme A1 - Monguio, Maria A1 - Romero-Gómez, Merce A1 - Altamirano, Diego A1 - Antoja, Teresa A1 - Assaad, R. A1 - Cantat-Gaudin, Tristan A1 - Castro-Ginard, Alfred A1 - Enke, Harry A1 - Girardi, Léo A1 - Guiglion, Guillaume A1 - Khan, Saniya A1 - Luri, Xavier A1 - Miglio, Andrea A1 - Minchev, Ivan A1 - Ramos, Pau A1 - Santiago, Basillio Xavier A1 - Steinmetz, Matthias T1 - Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia EDR3 stars brighter than G=18.5 JF - Astronomy and astrophysics N2 - We present a catalogue of 362 million stellar parameters, distances, and extinctions derived from Gaia's Early Data Release (EDR3) cross-matched with the photometric catalogues of Pan-STARRS1, SkyMapper, 2MASS, and All WISE. The higher precision of the Gaia EDR3 data, combined with the broad wavelength coverage of the additional photometric surveys and the new stellar-density priors of the StarHorse code, allows us to substantially improve the accuracy and precision over previous photo-astrometric stellar-parameter estimates. At magnitude G = 14 (17), our typical precisions amount to 3% (15%) in distance, 0.13 mag (0.15 mag) in V-band extinction, and 140 K (180 K) in effective temperature. Our results are validated by comparisons with open clusters, as well as with asteroseismic and spectroscopic measurements, indicating systematic errors smaller than the nominal uncertainties for the vast majority of objects. We also provide distance- and extinction-corrected colour-magnitude diagrams, extinction maps, and extensive stellar density maps that reveal detailed substructures in the Milky Way and beyond. The new density maps now probe a much greater volume, extending to regions beyond the Galactic bar and to Local Group galaxies, with a larger total number density. We publish our results through an ADQL query interface (gaia . aip . de) as well as via tables containing approximations of the full posterior distributions. Our multi-wavelength approach and the deep magnitude limit render our results useful also beyond the next Gaia release, DR3. KW - stars: distances KW - stars: fundamental parameters KW - Galaxy: general KW - Galaxy: stellar content KW - Galaxy: structure Y1 - 2022 U6 - https://doi.org/10.1051/0004-6361/202142369 SN - 0004-6361 SN - 1432-0746 VL - 658 PB - EDP Sciences CY - Les Ulis ER -