@article{QiuWegenerWirgesetal.2005, author = {Qiu, X. L. and Wegener, Michael and Wirges, Werner and Zhang, X. Q. and Hillenbrand, J. and Xia, Zhongfu and Gerhard, Reimund and Sessler, G. M.}, title = {Penetration of sulfur hexafluoride into cellular polypropylene films and its effect on the electric charging and electromechanical response of ferroelectrets}, issn = {0022-3727}, year = {2005}, abstract = {Cellular polypropylene (PP) films were treated with sulfur hexafluoride (SF6) gas in order to study the SF6 penetration behaviour and optimize the electric charging conditions. There were differences in the penetration of SF6 for different cellular PP materials, depending on the microscopic properties, which manifest themselves in the voided structure as well as in the mechanical stiffnesses of the cellular films. The penetration of SF6 after long-term pressure treatment is confirmed in strongly inflated cellular PP films with a low mechanical stiffness of about 1 MPa. No SF6 penetration occurs for slightly inflated cellular PP films with smaller void sizes and higher mechanical stiffnesses of around 5.8 MPa. The observed thickness variations, the higher charging fields during corona charging because of SF6 penetration and the SF6 environment, as well as the resulting electromechanical properties are discussed}, language = {en} } @article{YeungNollGibbinsetal.2011, author = {Yeung, Ching-man Au and Noll, Michael G. and Gibbins, Nicholas and Meinel, Christoph and Shadbolt, Nigel}, title = {Spear spamming-resistant expertise analysis and ranking incollaborative tagging systems}, series = {Computational intelligence}, volume = {27}, journal = {Computational intelligence}, number = {3}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0824-7935}, doi = {10.1111/j.1467-8640.2011.00384.x}, pages = {458 -- 488}, year = {2011}, abstract = {In this article, we discuss the notions of experts and expertise in resource discovery in the context of collaborative tagging systems. We propose that the level of expertise of a user with respect to a particular topic is mainly determined by two factors. First, an expert should possess a high-quality collection of resources, while the quality of a Web resource in turn depends on the expertise of the users who have assigned tags to it, forming a mutual reinforcement relationship. Second, an expert should be one who tends to identify interesting or useful resources before other users discover them, thus bringing these resources to the attention of the community of users. We propose a graph-based algorithm, SPEAR (spamming-resistant expertise analysis and ranking), which implements the above ideas for ranking users in a folksonomy. Our experiments show that our assumptions on expertise in resource discovery, and SPEAR as an implementation of these ideas, allow us to promote experts and demote spammers at the same time, with performance significantly better than the original hypertext-induced topic search algorithm and simple statistical measures currently used in most collaborative tagging systems.}, language = {en} } @article{HilleyBlisniukStrecker2005, author = {Hilley, G. E. and Blisniuk, Peter Michael and Strecker, Manfred}, title = {Mechanics and erosion of basement-cored uplift provinces}, year = {2005}, abstract = {Basement-cored uplift provinces are often characterized by high-angle reverse faulting along preexisting crustal heterogeneities, which may greatly affect the mechanics of deformation and the coupling between erosion and orogenic structure. Herein we construct a coupled deformation-erosion model to understand the mechanics and erosion of mountain belts in which the spatial distribution of deformation is largely influenced by the presence of preexisting high-angle faults. In this case, deformation is accommodated along, and topography is built above, these structures. This topographic loading leads to increasing lithostatic stresses beneath these regions. As a result, active deformation may migrate to frictionally stronger structures in adjacent regions where lithostatic loading is lower. The migration of deformation to such nearby structures depends on the Hubbert-Rubey pore fluid pressure ratio of the crust (lambda), the orientations of the frictionally weaker and stronger preexisting faults (beta(1) and beta(2), respectively), the friction coefficients (mu(b1) and mu(b2)) and Hubbert-Rubey fluid-pressure ratios (lambda(b1) and lambda(b2)) of these faults, and the surface slope of the topography above the frictionally weaker structure (alpha), assuming zero surface slope above the frictionally stronger structure. In general, we found that for a given alpha and beta(1), as mu(b1) increases lambda=lambda(b1)=lambda(b2) increases, and beta(2) decreases, the value of mu(b2) required to force deformation to migrate increases. However, as erosional processes lead to decreasing surface slopes, deformation will be inhibited from migrating to frictionally stronger structures in adjacent regions. Our model results may help to explain some aspects of the deformation observed and the possible correlation between precipitation and the migration of deformation within these tectonic provinces}, language = {en} } @article{BergnerStreckerTrauthetal.2009, author = {Bergner, Andreas G. N. and Strecker, Manfred and Trauth, Martin H. and Deino, Alan L. and Gasse, Francoise and Blisniuk, Peter Michael and Duehnforth, Miriam}, title = {Tectonic and climatic control on evolution of rift lakes in the Central Kenya Rift, East Africa}, issn = {0277-3791}, doi = {10.1016/j.quascirev.2009.07.008}, year = {2009}, abstract = {The long-term histories of the neighboring Nakuru-Elmenteita and Naivasha lake basins in the Central Kenya Rift illustrate the relative importance of tectonic versus climatic effects on rift-lake evolution and the formation of disparate sedimentary environments. Although modem climate conditions in the Central Kenya Rift are very similar for these basins, hydrology and hydrochemistry of present-day lakes Nakuru, Elmenteita and Naivasha contrast dramatically due to tectonically controlled differences in basin geometries, catchment size, and fluvial processes. In this study, we use eighteen C-14 and Ar-40/Ar-39 dated fluvio-lacustrine sedimentary sections to unravel the spatiotemporal evolution of the lake basins in response to tectonic and climatic influences. We reconstruct paleoclimatic and ecological trends recorded in these basins based on fossil diatom assemblages and geologic field mapping. Our study shows a tendency towards increasing alkalinity and shrinkage of water bodies in both lake basins during the last million years. Ongoing volcano-tectonic segmentation of the lake basins, as well as reorganization of upstream drainage networks have led to contrasting hydrologic regimes with adjacent alkaline and freshwater conditions. During extreme wet periods in the past, such as during the early Holocene climate optimum, lake levels were high and all basins evolved toward freshwater systems. During drier periods some of these lakes revert back to alkaline conditions, while others maintain freshwater characteristics. Our results have important implications for the use and interpretation of lake sediment as climate archives in tectonically active regions and emphasize the need to deconvolve lacustrine records with respect to tectonics versus climatic forcing mechanisms.}, language = {en} } @article{StankiewiczMunozRitteretal.2011, author = {Stankiewicz, Jacek and Munoz, G. and Ritter, Oliver and Bedrosian, Paul A. and Ryberg, Trond and Weckmann, Ute and Weber, Michael H.}, title = {Shallow lithological structure across the Dead Sea Transform derived from geophysical experiments}, series = {Geochemistry, geophysics, geosystems}, volume = {12}, journal = {Geochemistry, geophysics, geosystems}, number = {3-4}, publisher = {American Geophysical Union}, address = {Washington}, issn = {1525-2027}, doi = {10.1029/2011GC003678}, pages = {15}, year = {2011}, abstract = {In the framework of the DEad SEa Rift Transect (DESERT) project a 150 km magnetotelluric profile consisting of 154 sites was carried out across the Dead Sea Transform. The resistivity model presented shows conductive structures in the western section of the study area terminating abruptly at the Arava Fault. For a more detailed analysis we performed a joint interpretation of the resistivity model with a P wave velocity model from a partially coincident seismic experiment. The technique used is a statistical correlation of resistivity and velocity values in parameter space. Regions of high probability of a coexisting pair of values for the two parameters are mapped back into the spatial domain, illustrating the geographical location of lithological classes. In this study, four regions of enhanced probability have been identified, and are remapped as four lithological classes. This technique confirms the Arava Fault marks the boundary of a highly conductive lithological class down to a depth of similar to 3 km. That the fault acts as an impermeable barrier to fluid flow is unusual for large fault zone, which often exhibit a fault zone characterized by high conductivity and low seismic velocity. At greater depths it is possible to resolve the Precambrian basement into two classes characterized by vastly different resistivity values but similar seismic velocities. The boundary between these classes is approximately coincident with the Al Quweira Fault, with higher resistivities observed east of the fault. This is interpreted as evidence for the original deformation along the DST originally taking place at the Al Quweira Fault, before being shifted to the Arava Fault.}, language = {en} } @article{ComasBruHarrisonWerneretal.2019, author = {Comas-Bru, Laia and Harrison, Sandy P. and Werner, Martin and Rehfeld, Kira and Scroxton, Nick and Veiga-Pires, Cristina and Ahmad, Syed Masood and Brahim, Yassine Ait and Mozhdehi, Sahar Amirnezhad and Arienzo, Monica and Atsawawaranunt, Kamolphat and Baker, Andy and Braun, Kerstin and Breitenbach, Sebastian Franz Martin and Burstyn, Yuval and Chawchai, Sakonvan and Columbu, Andrea and Deininger, Michael and Demeny, Attila and Dixon, Bronwyn and Hatvani, Istvan Gabor and Hu, Jun and Kaushal, Nikita and Kern, Zoltan and Labuhn, Inga and Lachniet, Matthew S. and Lechleitner, Franziska A. and Lorrey, Andrew and Markowska, Monika and Nehme, Carole and Novello, Valdir F. and Oster, Jessica and Perez-Mejias, Carlos and Pickering, Robyn and Sekhon, Natasha and Wang, Xianfeng and Warken, Sophie and Atkinson, Tim and Ayalon, Avner and Baldini, James and Bar-Matthews, Miryam and Bernal, Juan Pablo and Boch, Ronny and Borsato, Andrea and Boyd, Meighan and Brierley, Chris and Cai, Yanjun and Carolin, Stacy and Cheng, Hai and Constantin, Silviu and Couchoud, Isabelle and Cruz, Francisco and Denniston, Rhawn and Dragusin, Virgil and Duan, Wuhui and Ersek, Vasile and Finne, Martin and Fleitmann, Dominik and Fohlmeister, Jens Bernd and Frappier, Amy and Genty, Dominique and Holzkamper, Steffen and Hopley, Philip and Johnston, Vanessa and Kathayat, Gayatri and Keenan-Jones, Duncan and Koltai, Gabriella and Li, Ting-Yong and Lone, Mahjoor Ahmad and Luetscher, Marc and Mattey, Dave and Moreno, Ana and Moseley, Gina and Psomiadis, David and Ruan, Jiaoyang and Scholz, Denis and Sha, Lijuan and Smith, Andrew Christopher and Strikis, Nicolas and Treble, Pauline and Unal-Imer, Ezgi and Vaks, Anton and Vansteenberge, Stef and Voarintsoa, Ny Riavo G. and Wong, Corinne and Wortham, Barbara and Wurtzel, Jennifer and Zhang, Haiwei}, title = {Evaluating model outputs using integrated global speleothem records of climate change since the last glacial}, series = {Climate of the past : an interactive open access journal of the European Geosciences Union}, volume = {15}, journal = {Climate of the past : an interactive open access journal of the European Geosciences Union}, number = {4}, publisher = {Copernicus}, address = {G{\"o}ttingen}, organization = {SISAL Working Grp}, issn = {1814-9324}, doi = {10.5194/cp-15-1557-2019}, pages = {1557 -- 1579}, year = {2019}, abstract = {Although quantitative isotope data from speleothems has been used to evaluate isotope-enabled model simulations, currently no consensus exists regarding the most appropriate methodology through which to achieve this. A number of modelling groups will be running isotope-enabled palaeoclimate simulations in the framework of the Coupled Model Intercomparison Project Phase 6, so it is timely to evaluate different approaches to using the speleothem data for data-model comparisons. Here, we illustrate this using 456 globally distributed speleothem δ18O records from an updated version of the Speleothem Isotopes Synthesis and Analysis (SISAL) database and palaeoclimate simulations generated using the ECHAM5-wiso isotope-enabled atmospheric circulation model. We show that the SISAL records reproduce the first-order spatial patterns of isotopic variability in the modern day, strongly supporting the application of this dataset for evaluating model-derived isotope variability into the past. However, the discontinuous nature of many speleothem records complicates the process of procuring large numbers of records if data-model comparisons are made using the traditional approach of comparing anomalies between a control period and a given palaeoclimate experiment. To circumvent this issue, we illustrate techniques through which the absolute isotope values during any time period could be used for model evaluation. Specifically, we show that speleothem isotope records allow an assessment of a model's ability to simulate spatial isotopic trends. Our analyses provide a protocol for using speleothem isotope data for model evaluation, including screening the observations to take into account the impact of speleothem mineralogy on δ18O values, the optimum period for the modern observational baseline and the selection of an appropriate time window for creating means of the isotope data for palaeo-time-slices.}, language = {en} } @misc{PaijmansBarlowHennebergeretal.2020, author = {Paijmans, Johanna L. A. and Barlow, Axel and Henneberger, Kirstin and Fickel, J{\"o}rns and Hofreiter, Michael and Foerste, Daniel W. G.}, title = {Ancestral mitogenome capture of the Southeast Asian banded linsang}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {972}, issn = {1866-8372}, doi = {10.25932/publishup-47444}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-474441}, pages = {14}, year = {2020}, abstract = {Utilising a reconstructed ancestral mitochondrial genome of a clade to design hybridisation capture baits can provide the opportunity for recovering mitochondrial sequences from all its descendent and even sister lineages. This approach is useful for taxa with no extant close relatives, as is often the case for rare or extinct species, and is a viable approach for the analysis of historical museum specimens. Asiatic linsangs (genus Prionodon) exemplify this situation, being rare Southeast Asian carnivores for which little molecular data is available. Using ancestral capture we recover partial mitochondrial genome sequences for seven banded linsangs (P. linsang) from historical specimens, representing the first intraspecific genetic dataset for this species. We additionally assemble a high quality mitogenome for the banded linsang using shotgun sequencing for time-calibrated phylogenetic analysis. This reveals a deep divergence between the two Asiatic linsang species (P. linsang, P. pardicolor), with an estimated divergence of ~12 million years (Ma). Although our sample size precludes any robust interpretation of the population structure of the banded linsang, we recover two distinct matrilines with an estimated tMRCA of ~1 Ma. Our results can be used as a basis for further investigation of the Asiatic linsangs, and further demonstrate the utility of ancestral capture for studying divergent taxa without close relatives.}, language = {en} } @article{MerzKuhlickeKunzetal.2020, author = {Merz, Bruno and Kuhlicke, Christian and Kunz, Michael and Pittore, Massimiliano and Babeyko, Andrey and Bresch, David N. and Domeisen, Daniela I. and Feser, Frauke and Koszalka, Inga and Kreibich, Heidi and Pantillon, Florian and Parolai, Stefano and Pinto, Joaquim G. and Punge, Heinz J{\"u}rgen and Rivalta, Eleonora and Schr{\"o}ter, Kai and Strehlow, Karen and Weisse, Ralf and Wurpts, Andreas}, title = {Impact forecasting to support emergency management of natural hazards}, series = {Reviews of geophysics}, volume = {58}, journal = {Reviews of geophysics}, number = {4}, publisher = {American Geophysical Union}, address = {Washington}, issn = {8755-1209}, doi = {10.1029/2020RG000704}, pages = {52}, year = {2020}, abstract = {Forecasting and early warning systems are important investments to protect lives, properties, and livelihood. While early warning systems are frequently used to predict the magnitude, location, and timing of potentially damaging events, these systems rarely provide impact estimates, such as the expected amount and distribution of physical damage, human consequences, disruption of services, or financial loss. Complementing early warning systems with impact forecasts has a twofold advantage: It would provide decision makers with richer information to take informed decisions about emergency measures and focus the attention of different disciplines on a common target. This would allow capitalizing on synergies between different disciplines and boosting the development of multihazard early warning systems. This review discusses the state of the art in impact forecasting for a wide range of natural hazards. We outline the added value of impact-based warnings compared to hazard forecasting for the emergency phase, indicate challenges and pitfalls, and synthesize the review results across hazard types most relevant for Europe.}, language = {en} } @article{PaijmansBarlowHennebergeretal.2020, author = {Paijmans, Johanna L. A. and Barlow, Axel and Henneberger, Kirstin and Fickel, J{\"o}rns and Hofreiter, Michael and Foerste, Daniel W. G.}, title = {Ancestral mitogenome capture of the Southeast Asian banded linsang}, series = {PLoS ONE}, volume = {15}, journal = {PLoS ONE}, number = {6}, publisher = {PLOS}, address = {San Francisco, California, US}, issn = {1932-6203}, doi = {10.1371/journal.pone.0234385}, pages = {12}, year = {2020}, abstract = {Utilising a reconstructed ancestral mitochondrial genome of a clade to design hybridisation capture baits can provide the opportunity for recovering mitochondrial sequences from all its descendent and even sister lineages. This approach is useful for taxa with no extant close relatives, as is often the case for rare or extinct species, and is a viable approach for the analysis of historical museum specimens. Asiatic linsangs (genus Prionodon) exemplify this situation, being rare Southeast Asian carnivores for which little molecular data is available. Using ancestral capture we recover partial mitochondrial genome sequences for seven banded linsangs (P. linsang) from historical specimens, representing the first intraspecific genetic dataset for this species. We additionally assemble a high quality mitogenome for the banded linsang using shotgun sequencing for time-calibrated phylogenetic analysis. This reveals a deep divergence between the two Asiatic linsang species (P. linsang, P. pardicolor), with an estimated divergence of ~12 million years (Ma). Although our sample size precludes any robust interpretation of the population structure of the banded linsang, we recover two distinct matrilines with an estimated tMRCA of ~1 Ma. Our results can be used as a basis for further investigation of the Asiatic linsangs, and further demonstrate the utility of ancestral capture for studying divergent taxa without close relatives.}, language = {en} } @misc{NeumannHorstkemperKruegeretal.2002, author = {Neumann, Bernhard and Horstkemper, Marianne and Kr{\"u}ger, Wolfgang and Wilkens, Martin and Bohlen, Andreas and Fr{\"u}bing, Peter and Wegener, Michael and Scheff, Ullrich and Neher, Dieter and Brehmer, Ludwig and Kleinpeter, Erich and Wolf, Gunter and Koetz, Joachim and Peter, Martin G. and Senkbeil, Sigrid and Meyer, Till}, title = {Portal = Im Trend: Physiker und Chemiker erforschen "Soft Matter"}, volume = {2002}, issn = {1618-6893}, doi = {10.25932/publishup-50144}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-501441}, pages = {40}, year = {2002}, abstract = {Aus dem Inhalt: Im Trend: Physiker und Chemiker erforschen „Soft Matter" -Brandenburger Netzwerk f{\"u}r Existenzgr{\"u}nder erh{\"a}lt F{\"o}rderung -Universit{\"a}t leistet Beitrag zum Romantik-Jahr -Musiksender MTV und Bryan Adams auf dem Campus}, language = {de} }