Refine
Year of publication
- 2011 (2047) (remove)
Document Type
- Article (1322)
- Doctoral Thesis (289)
- Monograph/Edited Volume (165)
- Review (96)
- Postprint (67)
- Conference Proceeding (29)
- Other (21)
- Master's Thesis (15)
- Part of Periodical (13)
- Preprint (9)
- Part of a Book (8)
- Working Paper (7)
- Habilitation Thesis (3)
- Moving Images (1)
- Journal/Publication series (1)
- Report (1)
Language
Keywords
- Deutschland (17)
- Bürgerschaft (16)
- Germany (16)
- Integration (16)
- International Politics (16)
- Internationale Politik (16)
- Migration (16)
- Politische Theorie (16)
- Afghanistan (15)
- Friedens- und Konfliktforschung (14)
Institute
- Institut für Biochemie und Biologie (242)
- Institut für Physik und Astronomie (187)
- Institut für Chemie (176)
- Institut für Geowissenschaften (141)
- Institut für Romanistik (141)
- Wirtschaftswissenschaften (104)
- Department Psychologie (79)
- Sozialwissenschaften (73)
- MenschenRechtsZentrum (72)
- WeltTrends e.V. Potsdam (70)
- Historisches Institut (66)
- Department Linguistik (65)
- Institut für Informatik und Computational Science (54)
- Institut für Ernährungswissenschaft (52)
- Institut für Slavistik (52)
- Institut für Anglistik und Amerikanistik (49)
- Institut für Germanistik (46)
- Institut für Jüdische Studien und Religionswissenschaft (41)
- Institut für Mathematik (38)
- Hasso-Plattner-Institut für Digital Engineering gGmbH (33)
- Vereinigung für Jüdische Studien e. V. (32)
- Extern (31)
- Philosophische Fakultät (28)
- Department Sport- und Gesundheitswissenschaften (27)
- Öffentliches Recht (27)
- Bürgerliches Recht (26)
- Department Erziehungswissenschaft (26)
- Institut für Künste und Medien (24)
- Institut für Umweltwissenschaften und Geographie (21)
- Mathematisch-Naturwissenschaftliche Fakultät (18)
- Zentrum für Qualitätsentwicklung in Lehre und Studium (ZfQ) (14)
- Moses Mendelssohn Zentrum für europäisch-jüdische Studien e. V. (13)
- Strafrecht (8)
- Sonderforschungsbereich 632 - Informationsstruktur (6)
- Strukturbereich Bildungswissenschaften (6)
- Humanwissenschaftliche Fakultät (4)
- Institut für Religionswissenschaft (4)
- Wirtschafts- und Sozialwissenschaftliche Fakultät (4)
- Kommunalwissenschaftliches Institut (3)
- Referat für Presse- und Öffentlichkeitsarbeit (3)
- Strukturbereich Kognitionswissenschaften (3)
- Zentrum für Lehrerbildung und Bildungsforschung (ZeLB) (3)
- Fachgruppe Politik- & Verwaltungswissenschaft (2)
- Zentrum für Sprachen und Schlüsselkompetenzen (Zessko) (2)
- Department Grundschulpädagogik (1)
- Fachgruppe Soziologie (1)
- Gleichstellungsbeauftragte (1)
- Institut für Philosophie (1)
- Juristische Fakultät (1)
- Klassische Philologie (1)
- Lehreinheit für Wirtschafts-Arbeit-Technik (1)
- Potsdam Transfer - Zentrum für Gründung, Innovation, Wissens- und Technologietransfer (1)
- Universitätsbibliothek (1)
- Verband für Patholinguistik e. V. (vpl) (1)
A study with 199 Polish adolescents explored the prominence of risk factors of sexual aggression as part of the sexual scripts for consensual sexual encounters and as predictors of the acceptance of sexual aggression. Distinguishing between general scripts, attributed to the age group as a whole, and individual scripts, reflecting personal standards, sexual scripts were linked to the normative endorsement of the risk factors and to the acceptance of sexual aggression. Individual scripts contained fewer risk factors of sexual aggression than general scripts. The more prominently the risk elements featured in the individual (but not in the general) scripts, the more they were seen as acceptable. For boys, risk scores in individual scripts were correlated with sexual behaviour and linked to the acceptance of sexual aggression via their normative endorsement. The distinction between individual and general scripts as guidelines for behaviour is discussed in terms of its significance for the understanding of sexual aggression.
We present XMM-Newton and Chandra observations of the born-again planetary nebula A 30. These X-ray observations reveal a bright unresolved source at the position of the central star whose X-ray luminosity exceeds by far the model expectations for photospheric emission and for shocks within the stellar wind. We suggest that a “born-again hot bubble” may be responsible for this X-ray emission. Diffuse X-ray emission associated with the petal-like features and one of the H-poor knots seen in the optical is also found. The weakened emission of carbon lines in the spectrum of the diffuse emission can be interpreted as the dilution of stellar wind by mass-loading or as the detection of material ejected during a very late thermal pulse.
Most 2.5D controlled-source electromagnetic (CSEM) modeling algorithms presented to date explicitly consider only sources that are point dipoles oriented parallel or perpendicular to the direction of constant conductivity. This makes simulations of complex source geometries expensive, requiring separate evaluations of many point dipole fields, and thus limits the practical applicability of such schemes for simulating and interpreting field data. We present a novel 2.5D CSEM modeling scheme that overcomes this limitation and permits efficient simulations of sources with general shape and orientation by evaluating fields for the entire source at once. We accommodate general sources by using a secondary field approach, in which primary fields are computed for the general source and a 1D background conductivity model. To carry out the required Fourier transforms between space and wavenumber domain using the same fast cosine and sine transform filters as in conventional algorithms, we split the primary and secondary fields into their symmetric and antisymmetric parts. For complex 3D source geometries, this approach is significantly more efficient than previous 2.5D algorithms. Our finite-difference algorithm also includes novel approaches for divergence correction at low frequencies and EM field interpolation across conductivity discontinuities. We describe the modeling scheme and demonstrate its accuracy and efficiency by comparisons of 2.5D-simulated data with 1D and 3D results.
Shallow lithological structure across the Dead Sea Transform derived from geophysical experiments
(2011)
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.
The seismicity pattern along the San Andreas fault near Parkfield and Cholame, California, varies distinctly over a length of only fifty kilometres. Within the brittle crust, the presence of frictionally weak minerals, fault-weakening high fluid pressures and chemical weakening are considered possible causes of an anomalously weak fault northwest of Parkfield(1-4). Non-volcanic tremor from lower-crustal and upper-mantle depths(5-7) is most pronounced about thirty kilometres southeast of Parkfield and is thought to be associated with high pore-fluid pressures at depth(8). Here we present geophysical evidence of fluids migrating into the creeping section of the San Andreas fault that seem to originate in the region of the uppermost mantle that also stimulates tremor, and evidence that along-strike variations in tremor activity and amplitude are related to strength variations in the lower crust and upper mantle. Interconnected fluids can explain a deep zone of anomalously low electrical resistivity that has been imaged by magnetotelluric data southwest of the Parkfield-Cholame segment. Near Cholame, where fluids seem to be trapped below a high-resistivity cap, tremor concentrates adjacent to the inferred fluids within a mechanically strong zone of high resistivity. By contrast, sub-vertical zones of low resistivity breach the entire crust near the drill hole of the San Andreas Fault Observatory at Depth, northwest of Parkfield, and imply pathways for deep fluids into the eastern fault block, coincident with a mechanically weak crust and the lower tremor amplitudes in the lower crust. Fluid influx to the fault system is consistent with hypotheses of fault-weakening high fluid pressures in the brittle crust.
The prevailing paradigm in aquatic science is that microbial methanogenesis happens primarily in anoxic environments. Here, we used multiple complementary approaches to show that microbial methane production could and did occur in the well-oxygenated water column of an oligotrophic lake (Lake Stechlin, Germany). Oversaturation of methane was repeatedly recorded in the well-oxygenated upper 10 m of the water column, and the methane maxima coincided with oxygen oversaturation at 6 m. Laboratory incubations of unamended epilimnetic lake water and inoculations of photoautotrophs with a lake-enrichment culture both led to methane production even in the presence of oxygen, and the production was not affected by the addition of inorganic phosphate or methylated compounds. Methane production was also detected by in-lake incubations of lake water, and the highest production rate was 1.8-2.4 nM.h(-1) at 6 m, which could explain 33-44% of the observed ambient methane accumulation in the same month. Temporal and spatial uncoupling between methanogenesis and methanotrophy was supported by field and laboratory measurements, which also helped explain the oversaturation of methane in the upper water column. Potentially methanogenic Archaea were detected in situ in the oxygenated, methane-rich epilimnion, and their attachment to photoautotrophs might allow for anaerobic growth and direct transfer of substrates for methane production. Specific PCR on mRNA of the methyl coenzyme M reductase A gene revealed active methanogenesis. Microbial methane production in oxygenated water represents a hitherto overlooked source of methane and can be important for carbon cycling in the aquatic environments and water to air methane flux.