TY - GEN A1 - Cohen, Abby A1 - Campisano, Christopher A1 - Arrowsmith, J. Ramon A1 - Asrat, Asfawossen A1 - Behrensmeyer, A. K. A1 - Deino, A. A1 - Feibel, C. A1 - Hill, A. A1 - Johnson, R. A1 - Kingston, J. A1 - Lamb, Henry F. A1 - Lowenstein, T. A1 - Noren, A. A1 - Olago, D. A1 - Owen, Richard Bernhart A1 - Potts, R. A1 - Reed, Kate A1 - Renaut, R. A1 - Schäbitz, Frank A1 - Tiercelin, J.-J. A1 - Trauth, Martin H. A1 - Wynn, J. A1 - Ivory, S. A1 - Brady, K. A1 - O’Grady, R. A1 - Rodysill, J. A1 - Githiri, J. A1 - Russell, Joellen A1 - Foerster, Verena A1 - Dommain, René A1 - Rucina, J. S. A1 - Deocampo, D. A1 - Russell, J. A1 - Billingsley, A. A1 - Beck, C. A1 - Dorenbeck, G. A1 - Dullo, L. A1 - Feary, D. A1 - Garello, D. A1 - Gromig, R. A1 - Johnson, T. A1 - Junginger, Annett A1 - Karanja, M. A1 - Kimburi, E. A1 - Mbuthia, A. A1 - McCartney, Tannis A1 - McNulty, E. A1 - Muiruri, V. A1 - Nambiro, E. A1 - Negash, E. W. A1 - Njagi, D. A1 - Wilson, J. N. A1 - Rabideaux, N. A1 - Raub, Timothy A1 - Sier, Mark Jan A1 - Smith, P. A1 - Urban, J. A1 - Warren, M. A1 - Yadeta, M. A1 - Yost, Chad A1 - Zinaye, B. T1 - The Hominin Sites and Paleolakes Drilling Project BT - inferring the environmental context of human evolution from eastern African rift lake deposits T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest and controversy among paleoanthropologists for decades. Prior attempts to understand the environmental history side of this equation have centered around the study of outcrop sediments and fossils adjacent to where fossil hominins (ancestors or close relatives of modern humans) are found, or from the study of deep sea drill cores. However, outcrop sediments are often highly weathered and thus are unsuitable for some types of paleoclimatic records, and deep sea core records come from long distances away from the actual fossil and stone tool remains. The Hominin Sites and Paleolakes Drilling Project (HSPDP) was developed to address these issues. The project has focused its efforts on the eastern African Rift Valley, where much of the evidence for early hominins has been recovered. We have collected about 2 km of sediment drill core from six basins in Kenya and Ethiopia, in lake deposits immediately adjacent to important fossil hominin and archaeological sites. Collectively these cores cover in time many of the key transitions and critical intervals in human evolutionary history over the last 4 Ma, such as the earliest stone tools, the origin of our own genus Homo, and the earliest anatomically modern Homo sapiens. Here we document the initial field, physical property, and core description results of the 2012-2014 HSPDP coring campaign. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 611 KW - Turkana-Basin KW - Adar formation KW - climate-change KW - olorgesailie formation KW - Southern Ethiopia KW - global climate KW - Kenya Rift KW - Pleistocene KW - variability KW - patterns Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-412498 IS - 611 ER - TY - JOUR A1 - Lehmann, Andreas A1 - Scheffler, Christiane T1 - What does the mean menarcheal age mean?An analysis of temporal pattern in variability in a historical swiss population from the 19th and 20th centuries JF - American journal of human biology : the official journal of the Human Biology Council N2 - ObjectivesAge at menarche is one of the most important factors when observing growth and development. The aim of this study was to assess the temporal pattern in variability of menarcheal age for a historic Swiss population from the 19th and 20th centuries. ResultsMean menarcheal age declined from 17.34 years (n=358) around 1830 to 13.80 years (n=141) around 1950. Within-cohort variance decreased from 7.5 to 2.1 year(2). Skewness was negatively correlated with birth year (r=-0.58). ConclusionThis study provided evidence for a secular trend in various statistical parameters for age at menarche since the 19th century. Furthermore, the results of the analysis of temporal pattern in variability revealed that the secular trend in menarcheal age happened in two phases. Am. J. Hum. Biol. 28:705-713, 2016. (c) 2016 Wiley Periodicals, Inc. Y1 - 2016 U6 - https://doi.org/10.1002/ajhb.22854 SN - 1042-0533 SN - 1520-6300 VL - 28 SP - 705 EP - 713 PB - Wiley-Blackwell CY - Hoboken ER - TY - BOOK A1 - Schmidt, Thorsten Ingo ED - Gosch, Dietmar ED - Hufeld, Ulrich ED - Kirchhof, Gregor ED - Rust, Alexander ED - Schenke, Ralf ED - Tappe, Henning ED - Weitemeyer, Birgit T1 - Finanzierungspflichten und Konnexitätsprinzip BT - zur Konnexitätsrelevanz der Dynamisierungsklausel des § 19 KiBiz T3 - Recht der Steuern und der öffentlichen Finanzordnung ; 10 N2 - Die Finanzkrise der Kommunen beruht auch auf der Übertragung staatlicher Aufgaben ohne entsprechenden finanziellen Ausgleich. Davor sollen nun das grundgesetzliche Aufgabenübertragungsverbot vom Bund auf die Kommunen und die landesverfassungsrechtlichen Konnexitätsregeln beim Transfer vom Land auf die Kommunen schützen. Zwar ist anerkannt, dass diese Vorschriften für Sachaufgaben gelten. Doch ist streitig, ob dies auch für die Auferlegung von Finanzierungspflichten zu gelten hat. Der Autor vergleicht die landesverfassungsrechtlichen Bestimmungen in ihrer Auslegung durch das jeweilige Landesverfassungsgericht und arbeitet unter besonderer Berücksichtigung der nordrhein-westfälischen Rechtslage heraus, dass die Übertragungsvorschriften nicht umgangen werden dürfen. Übertragung einer Sachaufgabe und Auferlegung einer Finanzierungspflicht sind funktionell gleichwertig und beide konnexitätsrelevant. Der Autor ist Direktor des Kommunalwissenschaftlichen Instituts der Universität Potsdam. Y1 - 2016 SN - 978-3-8487-2822-0 PB - Nomos CY - Baden-Baden ER - TY - BOOK A1 - Schmidt, Thorsten Ingo ED - Brüning, Christoph ED - Schmidt, Thorsten Ingo T1 - Das Mitverwaltungsmodell T3 - Kommunalrechtliche Studien ; 3 N2 - Demographischer Wandel einerseits und zunehmende Aufgaben andererseits erzwingen bei finanzieller Notlage kommunale Reformen. Vielfach antworten die Landesgesetzgeber auf diesen Reformbedarf mit immer größeren kommunalen Einheiten. Um dieser „Flucht in die Einheitsgemeinde“ entgegenzuwirken, entwickelt der Verfasser das Mitverwaltungsmodell: Eine Gemeinde bleibt zwar rechtlich selbstständig, bedient sich aber der hauptamtlichen Verwaltung einer anderen Gemeinde. Die Möglichkeit einer solchen öffentlich-rechtlichen Geschäftsbesorgung wird unter Wahrung der Selbstverwaltungsgarantie beider Gemeinden entfaltet. Die notwendigen gesetzlichen Bestimmungen und vertraglichen Regelungen werden entworfen. Dieses Modell soll im Rahmen der Brandenburgischen Verwaltungsstrukturreform umgesetzt werden und kann auch anderen Ländern als Vorbild dienen. Der Autor ist Direktor des Kommunalwissenschaftlichen Instituts der Universität Potsdam. Y1 - 2016 SN - 978-3-8487-2797-1 PB - Nomos CY - Baden-Baden ER - TY - GEN A1 - Räling, Romy A1 - Hanne, Sandra A1 - Schröder, Astrid A1 - Keßler, Carla A1 - Wartenburger, Isabell T1 - Judging the animacy of words BT - the influence of typicality and age of acquisition in a semantic decision task N2 - The age at which members of a semantic category are learned (age of acquisition), the typicality they demonstrate within their corresponding category, and the semantic domain to which they belong (living, non-living) are known to influence the speed and accuracy of lexical/semantic processing. So far, only a few studies have looked at the origin of age of acquisition and its interdependence with typicality and semantic domain within the same experimental design. Twenty adult participants performed an animacy decision task in which nouns were classified according to their semantic domain as being living or non-living. Response times were influenced by the independent main effects of each parameter: typicality, age of acquisition, semantic domain, and frequency. However, there were no interactions. The results are discussed with respect to recent models concerning the origin of age of acquisition effects. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 305 KW - Age of acquisition KW - Animacy decision KW - Semantic classification task KW - Typicality Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-98402 ER - TY - JOUR A1 - Cui, Pin A1 - Löber, Ulrike A1 - Alquezar-Planas, David E. A1 - Ishida, Yasuko A1 - Courtiol, Alexandre A1 - Timms, Peter A1 - Johnson, Rebecca N. A1 - Lenz, Dorina A1 - Helgen, Kristofer M. A1 - Roca, Alfred L. A1 - Hartman, Stefanie A1 - Greenwood, Alex D. T1 - Comprehensive profiling of retroviral integration sites using target enrichment methods from historical koala samples without an assembled reference genome JF - PeerJ N2 - Background. Retroviral integration into the host germline results in permanent viral colonization of vertebrate genomes. The koala retrovirus (KoRV) is currently invading the germline of the koala (Phascolarctos cinereus) and provides a unique opportunity for studying retroviral endogenization. Previous analysis of KoRV integration patterns in modern koalas demonstrate that they share integration sites primarily if they are related, indicating that the process is currently driven by vertical transmission rather than infection. However, due to methodological challenges, KoRV integrations have not been comprehensively characterized. Results. To overcome these challenges, we applied and compared three target enrichment techniques coupled with next generation sequencing (NGS) and a newly customized sequence-clustering based computational pipeline to determine the integration sites for 10 museum Queensland and New South Wales (NSW) koala samples collected between the 1870s and late 1980s. A secondary aim of this study sought to identify common integration sites across modern and historical specimens by comparing our dataset to previously published studies. Several million sequences were processed, and the KoRV integration sites in each koala were characterized. Conclusions. Although the three enrichment methods each exhibited bias in integration site retrieval, a combination of two methods, Primer Extension Capture and hybridization capture is recommended for future studies on historical samples. Moreover, identification of integration sites shows that the proportion of integration sites shared between any two koalas is quite small. KW - Integration sites KW - Retroviral endogenization KW - KoRV KW - Target enrichment KW - Clustering Y1 - 2016 U6 - https://doi.org/10.7717/peerj.1847 SN - 2167-8359 VL - 4 PB - PeerJ Inc. CY - London ER - TY - THES A1 - Bojahr, Andre T1 - Hypersound interaction studied by time-resolved inelastic light and x-ray scattering T1 - Wechselwirkende Hyperschallwellen untersucht mittels zeitaufgelöster inelastischer Licht- und Röntgenstreuung N2 - This publications-based thesis summarizes my contribution to the scientific field of ultrafast structural dynamics. It consists of 16 publications, about the generation, detection and coupling of coherent gigahertz longitudinal acoustic phonons, also called hypersonic waves. To generate such high frequency phonons, femtosecond near infrared laser pulses were used to heat nanostructures composed of perovskite oxides on an ultrashort timescale. As a consequence the heated regions of such a nanostructure expand and a high frequency acoustic phonon pulse is generated. To detect such coherent acoustic sound pulses I use ultrafast variants of optical Brillouin and x-ray scattering. Here an incident optical or x-ray photon is scattered by the excited sound wave in the sample. The scattered light intensity measures the occupation of the phonon modes. The central part of this work is the investigation of coherent high amplitude phonon wave packets which can behave nonlinearly, quite similar to shallow water waves which show a steepening of wave fronts or solitons well known as tsunamis. Due to the high amplitude of the acoustic wave packets in the solid, the acoustic properties can change significantly in the vicinity of the sound pulse. This may lead to a shape change of the pulse. I have observed by time-resolved Brillouin scattering, that a single cycle hypersound pulse shows a wavefront steepening. I excited hypersound pulses with strain amplitudes until 1% which I have calibrated by ultrafast x-ray diffraction (UXRD). On the basis of this first experiment we developed the idea of the nonlinear mixing of narrowband phonon wave packets which we call "nonlinear phononics" in analogy with the nonlinear optics, which summarizes a kaleidoscope of surprising optical phenomena showing up at very high electric fields. Such phenomena are for instance Second Harmonic Generation, four-wave-mixing or solitons. But in case of excited coherent phonons the wave packets have usually very broad spectra which make it nearly impossible to look at elementary scattering processes between phonons with certain momentum and energy. For that purpose I tested different techniques to excite narrowband phonon wave packets which mainly consist of phonons with a certain momentum and frequency. To this end epitaxially grown metal films on a dielectric substrate were excited with a train of laser pulses. These excitation pulses drive the metal film to oscillate with the frequency given by their inverse temporal displacement and send a hypersonic wave of this frequency into the substrate. The monochromaticity of these wave packets was proven by ultrafast optical Brillouin and x-ray scattering. Using the excitation of such narrowband phonon wave packets I was able to observe the Second Harmonic Generation (SHG) of coherent phonons as a first example of nonlinear wave mixing of nanometric phonon wave packets. N2 - Diese publikationsbasierte Dissertation fasst meinen Beitrag zum Forschungsgebiet der ultraschnellen Strukturdynamik zusammen. Diese Arbeit besteht aus 16 Publikationen aus den Bereichen der Erzeugung, Detektion und Kopplung von kohärenten Gigahertz longitudinal-akustischen Phononen, auch Hyperschallwellen genannt. Um solch hochfrequente Phononen zu erzeugen, werden Femtosekunden nahinfrarot Laserpulse benutzt, um Nanostrukturen auf einer ultraschnellen Zeitskala zu erhitzen. Die aufgeheizten Regionen der Nanostruktur dehnen sich aufgrund der hohen Temperatur aus und ein hochfrequenter Schallpuls wird generiert. Um solche akustischen Pulse zu detektieren benutze ich ultraschnelle Varianten der Brillouin- und Röntgenstreuung. Dabei wird ein einfallendes optisches oder Röntgenphoton an der erzeugten Schallwelle gestreut. Die gemessene Streuintensität ist hierbei ein Maß für die Besetzung einzelner Phononenzustände. Der zentrale Teil dieser Arbeit ist die Untersuchung von kohärenten Phonon-Wellenpaketen mit sehr hoher Amplitude. Diese Wellenpakete können sich nichtlinear verhalten, sehr ähnlich zu Flachwasserwellen bei denen nichtlineare Effekte in Form eines Aufsteilens der Wellenfronten oder der Existenz von Solitonen, bekannt als Tsunamis, äußern. Durch die hohe Amplitude der akustischen Wellenpakete können sich die akustischen Eigenschaften des Festkörpers in der Umgebung des Schallpulses signifikant ändern, welches sich dann in einer Formänderung des Schallpulses widerspiegelt. Ich konnte mittels zeitaufgelöster Brillouinstreuung das Aufsteilen der Wellenfronten eines Hyperschallpulses bestehend aus einem einzigen Oszillationszyklus beobachten. Hierbei wurden Hyperschallwellen mit einer Dehnungsamplitude von bis zu 1% angeregt, wobei ich diesen Wert mittels ultraschneller Röntgenbeugung kalibrieren konnte. Mit diesem ersten Experiment als Basis entwickelten wir die Idee der nichtlinearen Wellenmischung von schmalbandigen Phonon-Wellenpaketen unter dem Titel "nichtlineare Phononik" in Analogie zur nichtlinearen Optik, welche sich aus einer Reihe von verblüffenden optischen Phänomenen bei sehr hohen elektrischen Feldstärken zusammensetzt. Solche Phänomene sind z. B. die optische Frequenzverdopplung, das Vier-Wellen-Mischen oder Solitone. Nur sind im Falle von kohärenten Phononen die erzeugten Spektren sehr breitbandig, was die Untersuchung von spezifischen Phononen mit festem Impuls und definierter Frequenz fast unmöglich macht. Aus diesem Grund testete ich verschiedene Methoden um schmalbandige Phonon-Wellenpakete anzuregen, welche im Wesentlichen aus Phononen bestimmten Impulses und definierter Frequenz bestehen. Dafür wurden schließ lich epitaktisch auf ein dielektrisches Substrat aufgewachsene Metallfilme mit einen Laserpulszug angeregt. Hier sorgen die Lichtpulse für eine periodische Oszillation des Metalfilms, wobei die Anregefrequenz durch den inversen zeitlichen Abstand der Lichtpulse gegeben ist. Diese periodische Oszillation sendet dann ein Hyperschallwellenpaket eben dieser Frequenz ins Substrat. Die Monochromie dieser Wellenpakete konnte dabei mittels ultraschneller Brillouin- und Röntgenstreuung bestätigt werden. Durch die Benutzung dieser schmalbandigen Phonon-Wellenpakete war es mir möglich, die Frequenzverdopplung (SHG) von kohärenten Phononen zu beobachten, was ein erstes Beispiel für die nichtlineare Wellenmischung von nanometrischen Phonon-Wellenpaketen ist. KW - hypersound KW - nonlinear acoustics KW - ultrafast KW - Brillouin scattering KW - x-ray diffraction KW - self-steepening KW - second-harmonic generation KW - Phononen KW - Wechselwirkung KW - Anharmonizität KW - nichtlineare Wellenmischung KW - zweite Harmonische KW - Phononenstreuung KW - nichlineare Phononik Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-93860 ER - TY - JOUR A1 - Iurchuk, V. A1 - Schick, D. A1 - Bran, J. A1 - Colson, D. A1 - Forget, A. A1 - Halley, D. A1 - Koc, Azize A1 - Reinhardt, Mathias A1 - Kwamen, C. A1 - Morley, N. A. A1 - Bargheer, Matias A1 - Viret, M. A1 - Gumeniuk, R. A1 - Schmerber, G. A1 - Doudin, B. A1 - Kundys, B. T1 - Optical Writing of Magnetic Properties by Remanent Photostriction JF - Physical review letters N2 - We present an optically induced remanent photostriction in BiFeO3, resulting from the photovoltaic effect, which is used to modify the ferromagnetism of Ni film in a hybrid BiFeO3/Ni structure. The 75% change in coercivity in the Ni film is achieved via optical and nonvolatile control. This photoferromagnetic effect can be reversed by static or ac electric depolarization of BiFeO3. Hence, the strain dependent changes in magnetic properties are written optically, and erased electrically. Light-mediated straintronics is therefore a possible approach for low-power multistate control of magnetic elements relevant for memory and spintronic applications. Y1 - 2016 U6 - https://doi.org/10.1103/PhysRevLett.117.107403 SN - 0031-9007 SN - 1079-7114 VL - 117 PB - American Physical Society CY - College Park ER - TY - JOUR A1 - Reinhardt, Matthias A1 - Koc, Azize A1 - Leitenberger, Wolfram A1 - Gaal, Peter A1 - Bargheer, Matias T1 - Optimized spatial overlap in optical pump-X-ray probe experiments with high repetition rate using laser-induced surface distortions JF - Journal of synchrotron radiation N2 - Ultrafast X-ray diffraction experiments require careful adjustment of the spatial overlap between the optical excitation and the X-ray probe pulse. This is especially challenging at high laser repetition rates. Sample distortions caused by the large heat load on the sample and the relatively low optical energy per pulse lead to only tiny signal changes. In consequence, this results in small footprints of the optical excitation on the sample, which turns the adjustment of the overlap difficult. Here a method for reliable overlap adjustment based on reciprocal space mapping of a laser excited thin film is presented. KW - ultrafast X-ray diffraction KW - nanostructures KW - surface deformation KW - heat diffusion KW - optical pump Y1 - 2016 U6 - https://doi.org/10.1107/S1600577515024443 SN - 1600-5775 VL - 23 SP - 474 EP - 479 PB - International Union of Crystallography CY - Chester ER - TY - JOUR A1 - Czesnick, Hjördis A1 - Lenhard, Michael T1 - Antagonistic control of flowering time by functionally specialized poly(A) polymerases in Arabidopsis thaliana JF - The plant journal N2 - Polyadenylation is a critical 3-end processing step during maturation of pre-mRNAs, and the length of the poly(A) tail affects mRNA stability, nuclear export and translation efficiency. The Arabidopsis thaliana genome encodes three canonical nuclear poly(A) polymerase (PAPS) isoforms fulfilling specialized functions, as reflected by their different mutant phenotypes. While PAPS1 affects several processes, such as the immune response, organ growth and male gametophyte development, the roles of PAPS2 and PAPS4 are largely unknown. Here we demonstrate that PAPS2 and PAPS4 promote flowering in a partially redundant manner. The enzymes act antagonistically to PAPS1, which delays the transition to flowering. The opposite flowering-time phenotypes in paps1 and paps2 paps4 mutants are at least partly due to decreased or increased FLC activity, respectively. In contrast to paps2 paps4 mutants, plants with increased PAPS4 activity flower earlier than the wild-type, concomitant with reduced FLC expression. Double mutant analyses suggest that PAPS2 and PAPS4 act independently of the autonomous pathway components FCA, FY and CstF64. The direct polyadenylation targets of the three PAPS isoforms that mediate their effects on flowering time do not include FLC sense mRNA and remain to be identified. Thus, our results uncover a role for canonical PAPS isoforms in flowering-time control, raising the possibility that modulating the balance of the isoform activities could be used to fine tune the transition to flowering. Significance Statement The length of the poly(A) tail affects mRNA stability, nuclear export and translation efficiency. Arabidopsis has three isoforms of nuclear poly(A) polymerase (PAPS): PAPS1 plays a major role in organ growth and plant defence. Here we show that PAPS2 and PAPS4 redundantly promote flowering and act antagonistically to PAPS1, which delays flowering. We suggest that modulating the activity of these isoforms fine-tunes the transition to flowering. KW - polyadenylation KW - 3-end processing KW - poly(A) polymerase KW - flowering time KW - autonomous pathway KW - Arabidopsis thaliana Y1 - 2016 U6 - https://doi.org/10.1111/tpj.13280 SN - 0960-7412 SN - 1365-313X VL - 88 SP - 570 EP - 583 PB - Wiley-Blackwell CY - Hoboken ER -