TY - JOUR A1 - Kolmakova, Olesya V. A1 - Gladyshev, Michail I. A1 - Fonvielle, Jeremy Andre A1 - Ganzert, Lars A1 - Hornick, Thomas A1 - Grossart, Hans-Peter T1 - Effects of zooplankton carcasses degradation on freshwater bacterial community composition and implications for carbon cycling JF - Environmental microbiology N2 - Non-predatory mortality of zooplankton provides an abundant, yet, little studied source of high quality labile organic matter (LOM) in aquatic ecosystems. Using laboratory microcosms, we followed the decomposition of organic carbon of fresh C-13-labelled Daphnia carcasses by natural bacterioplankton. The experimental setup comprised blank microcosms, that is, artificial lake water without any organic matter additions (B), and microcosms either amended with natural humic matter (H), fresh Daphnia carcasses (D) or both, that is, humic matter and Daphnia carcasses (HD). Most of the carcass carbon was consumed and respired by the bacterial community within 15 days of incubation. A shift in the bacterial community composition shaped by labile carcass carbon and by humic matter was observed. Nevertheless, we did not observe a quantitative change in humic matter degradation by heterotrophic bacteria in the presence of LOM derived from carcasses. However, carcasses were the main factor driving the bacterial community composition suggesting that the presence of large quantities of dead zooplankton might affect the carbon cycling in aquatic ecosystems. Our results imply that organic matter derived from zooplankton carcasses is efficiently remineralized by a highly specific bacterial community, but does not interfere with the bacterial turnover of more refractory humic matter. Y1 - 2018 U6 - https://doi.org/10.1111/1462-2920.14418 SN - 1462-2912 SN - 1462-2920 VL - 21 IS - 1 SP - 34 EP - 49 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Reindl, Nicole A1 - Bainbridge, M. A1 - Przybilla, Norbert A1 - Geier, Stephan A1 - Prvak, M. A1 - Krticka, Jiri A1 - Ostensen, R. H. A1 - Telting, J. A1 - Werner, K. T1 - Unravelling the baffling mystery of the ultrahot wind phenomenon in white dwarfs JF - Monthly notices of the Royal Astronomical Society N2 - The presence of ultrahigh excitation (UHE) absorption lines (e.g. OVIII) in the optical spectra of several of the hottest white dwarfs poses a decades-long mystery and is something that has never been observed in any other astrophysical object. The occurrence of such features requires a dense environment with temperatures near 10(6) K, by far exceeding the stellar effective temperature. Here we report the discovery of a new hot wind white dwarf, GALEXJ014636.8+323615. Astonishingly, we found for the first time rapid changes of the equivalent widths of the UHE features, which are correlated to the rotational period of the star (P=0.242035 d). We explain this with the presence of a wind-fed circumstellar magnetosphere in which magnetically confined wind shocks heat up the material to the high temperatures required for the creation of the UHE lines. The photometric and spectroscopic variability of GALEXJ014636.8+323615 can then be understood as consequence of the obliquity of the magnetic axis with respect to the rotation axis of the white dwarf. This is the first time a wind-fed circumstellar magnetosphere around an apparently isolated white dwarf has been discovered and finally offers a plausible explanation of the ultrahot wind phenomenon. KW - stars: AGB and post-AGB KW - stars: evolution KW - stars: magnetic field Y1 - 2018 U6 - https://doi.org/10.1093/mnrasl/sly191 SN - 0035-8711 SN - 1365-2966 VL - 482 IS - 1 SP - L93 EP - L98 PB - Oxford Univ. Press CY - Oxford ER - TY - RPRT A1 - Stieglitz, Stefan A1 - Zerfaß, Ansgar A1 - Wloka, Michelle A1 - Clausen, Sünje T1 - Communications trend radar 2024 BT - information inflation, AI literacy, workforce shift, content integrity & decoding humans T2 - Communication insights N2 - What does the future hold for corporate communications? The Communications Trend Radar is an applied research project. On an annual basis, it identifies relevant trends for corporate communications from the fields of society, management, and technology. The research team at the University of Potsdam (Professor Stefan Stieglitz, Sünje Clausen, MS.) and Leipzig University (Professor Ansgar Zerfass, Dr Michelle Wloka) identified the following trends for 2024: Information Inflation, AI Literacy, Workforce Shift, Content Integrity, Decoding Humans. More information on the trends can be found in the Communications Trend Radar Report 2024 N2 - Wo steht die Kommunikationsbranche und wohin wird sie sich entwickeln? Der Communications Trend Radar ist eine wissenschaftliche, interessensunabhängige Studie, die jedes Jahr relevante Trends für die Unternehmenskommunikation aus den Bereichen Gesellschaft, Management und Technologie herausarbeitet. Das Forschungsteam der Universität Potsdam (Prof. Dr. Stefan Stieglitz, Sünje Clausen, M.Sc.) und der Universität Leipzig (Prof. Dr. Ansgar Zerfaß, Dr. Michelle Wloka) identifiziert für 2024 die Trends: Information Inflation, AI Literacy, Workforce Shift, Content Integrity, Decoding Humans. Weitere Informationen zu den Trends können im Communications Trend Radar Report 2024 nachgelesen werden. Y1 - 2024 UR - https://hdl.handle.net/10419/284410 U6 - https://doi.org/10419/284410 SN - 2749-893X VL - 20 PB - Academic Society for Management & Communication CY - Leipzig ER - TY - RPRT A1 - Zerfaß, Ansgar A1 - Stieglitz, Stefan A1 - Clausen, Sünje A1 - Ziegele, Daniel A1 - Berger, Karen T1 - Communications trend radar 2023 BT - state revival, scarcity management, unimagination, augmented workflows & parallel worlds T2 - Communication insights N2 - How do social changes, new technologies or new management trends affect communication work? A team of researchers at Leipzig University and the University of Potsdam (Germany) observed new developments in related disciplines. As a result, the five most important trends for corporate communications are identified annually and published in the Communications Trend Radar. Thus, Communications managers can identify challenges and opportunities at an early stage, take a position, address issues and make decisions. For 2023, the Communications Trend Radar identifies five key trends for corporate communications: State Revival, Scarcity Management, Unimagination, Parallel Worlds, Augemented Workflows. KW - public relation KW - trend KW - country KW - stakeholders KW - bottleneck KW - resilience KW - artificial intelligence KW - virtual reality Y1 - 2023 UR - https://hdl.handle.net/10419/270993 U6 - https://doi.org/10419/270993 SN - 2749-893X VL - 17 PB - Academic Society for Management & Communication CY - Leipzig ER - TY - RPRT A1 - Clausen, Sünje A1 - Stieglitz, Stefan A1 - Wloka, Michelle T1 - Between reality & fantasy BT - transforming influencer relations through synthetic media T2 - Communication insights N2 - Synthetische Medien ermöglichen die zunehmend automatisierte Erstellung virtueller Influencer, von denen bereits einige Millionen Follower in sozialen Medien gewonnen haben. Unter der Leitung von Professor Stefan Stieglitz und Sünje Clausen (Universität Potsdam) und in Kooperation mit Sanofi hat ein Forschungsprojekt untersucht, wie computergenerierten Charaktere für die Influencer-Kommunikation im Unternehmensumfeld genutzt werden können. Nähere Informationen zu den Forschungsergebnissen können in der Communication Insights nachgelesen werden: eine kurze Einführung in die Influencer-Kommunikation, potenziellen Vorteile als auch Herausforderungen von virtuellen Influencern, Tipps für den Prozess der Gestaltung und Nutzung eines virtuellen Influencers. Y1 - 2023 UR - https://hdl.handle.net/10419/280991 U6 - https://doi.org/10419/280991 SN - 2749-893X VL - 19 PB - Academic Society for Management & Communication CY - Leipzig ER - TY - JOUR A1 - Olen, Stephanie M. A1 - Bookhagen, Bodo A1 - Strecker, Manfred T1 - Corrigendum to: Olen, Stephanie M.; Bookhagen, Bodo; Strecker, Manfred R. : Role of climate and vegetation density in modulating denudation rates in the Himalaya. - Earth and planetary science letters. - 445 (2016), S. 57 - 67. - doi: https://doi.org/10.1016/j.epsl.2016.03.047 JF - Earth and planetary science letters N2 - Vegetation has long been hypothesized to influence the nature and rates of surface processes. We test the possible impact of vegetation and climate on denudation rates at orogen scale by taking advantage of a pronounced along-strike gradient in rainfall and vegetation density in the Himalaya. We combine 12 new 10Be denudation rates from the Sutlej Valley and 123 published denudation rates from fluvially- dominated catchments in the Himalaya with remotely-sensed measures of vegetation density and rainfall metrics, and with tectonic and lithologic constraints. In addition, we perform topographic analyses to assess the contribution of vegetation and climate in modulating denudation rates along strike. We observe variations in denudation rates and the relationship between denudation and topography along strike that are most strongly controlled by local rainfall amount and vegetation density, and cannot be explained by along-strike differences in tectonics or lithology. A W–E along-strike decrease in denudation rate variability positively correlates with the seasonality of vegetation density (R = 0.95, p < 0.05), and negatively correlates with mean vegetation density (R = −0.84, p < 0.05). Vegetation density modulates the topographic response to changing denudation rates, such that the functional relationship between denudation rate and topographic steepness becomes increasingly linear as vegetation density increases. We suggest that while tectonic processes locally control the pattern of denudation rates across strike of the Himalaya (i.e., S–N), along strike of the orogen (i.e., E–W) climate exerts a measurable influence on how denudation rates scatter around long-term, tectonically-controlled erosion, and on the functional relationship between topography and denudation Y1 - 2020 U6 - https://doi.org/10.1016/j.epsl.2020.116252 SN - 0012-821X SN - 1385-013X VL - 540 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Philipowski, Katharina A1 - Eming, Jutta T1 - Nachhaltig und dauerhaft verändert BT - Akademische Lehre nach der Corona-Pandemie JF - Forschung und Lehre N2 - Im Zuge der Pandemiebekämpfung und der Digitalisierung entstehen an den Universitäten neue Strukturen, die die akademische Lehre nachhaltig verändern werden. Die Autorinnen schlagen Rahmenbedingungen für die Etablierung digitaler Lehre vor. Y1 - 2022 UR - https://www.forschung-und-lehre.de/lehre/wie-corona-die-akademische-lehre-dauerhaft-veraendert-4678 UR - https://www.wissenschaftsmanagement-online.de/system/files/downloads-wimoarticle/f%26l5-22_Akademische_Lehre_nach_Corona_Eming_Philipowski.pdf SN - 0945-5604 VL - 29 IS - 5 SP - 364 EP - 365 PB - Deutscher Hochschulverband; ESV CY - Bonn ER - TY - JOUR A1 - Schaerer, Daniel A1 - Izotov, Yuri I. A1 - Worseck, Gábor A1 - Berg, Danielle A1 - Chisholm, John A1 - Jaskot, Anne A1 - Nakajima, Kimihiko A1 - Ravindranath, Swara A1 - Thuan, Trinh X. A1 - Verhamme, Anne T1 - Strong Lyman continuum emitting galaxies show intense C IV λ 1550 emission JF - Astronomy and astrophysics N2 - Using the Space Telescope Imaging Spectrograph, we have obtained ultraviolet spectra from similar to 1200 to 2000 angstrom of known Lyman continuum (LyC) emitting galaxies at low redshift (z similar to 0.3-0.4) with varying absolute LyC escape fractions ( f(esc) similar to 0.01-0.72). Our observations include in particular the galaxy J1243+4646, which has the highest known LyC escape fraction at low redshift. While all galaxies are known Lyman alpha emitters, we consistently detect an inventory of additional emission lines, including C IV lambda 1550, He II lambda 1640, O III] lambda 1666, and C III] lambda 1909, whose origin is presumably essentially nebular. C IV lambda 1550 emission is detected above 4 sigma in six out of eight galaxies, with equivalent widths of EW(C IV) = 12-15 angstrom for two galaxies, which exceeds the previously reported maximum emission in low-z star-forming galaxies. We detect C IV lambda 1550 emission in all LyC emitters with escape fractions f(esc) > 0.1 and find a tentative increase in the flux ratio C IV lambda 1550 /C III] lambda 1909 with f(esc). Based on the data, we propose a new criterion to select and classify strong leakers (galaxies with f(esc) > 0.1): C IV lambda 1550 /C III] lambda 1909 greater than or similar to 0.75. Finally, we also find He II lambda 1640 emission in all the strong leakers with equivalent widths from 3 to 8 angstrom rest frame. These are among the highest values observed in star-forming galaxies and are primarily due to a high rate of ionizing photon production. The nebular He II lambda 1640 emission of the strong LyC emitters does not require harder ionizing spectra at >54 eV compared to those of typical star-forming galaxies at similarly low metallicity. KW - galaxies: starburst KW - galaxies: high-redshift KW - dark ages, reionization KW - first stars KW - ultraviolet: galaxies Y1 - 2022 U6 - https://doi.org/10.1051/0004-6361/202243149 SN - 0004-6361 SN - 1432-0746 VL - 658 PB - EDP Sciences CY - Les Ulis ER -