@article{TiedemannIobbiNivolLeimkuehler2022, author = {Tiedemann, Kim and Iobbi-Nivol, Chantal and Leimk{\"u}hler, Silke}, title = {The Role of the Nucleotides in the Insertion of the bis-Molybdopterin Guanine Dinucleotide Cofactor into apo-Molybdoenzymes}, series = {Molecules}, volume = {27}, journal = {Molecules}, edition = {9}, publisher = {MDPI}, address = {Basel, Schweiz}, issn = {1420-3049}, doi = {10.3390/molecules27092993}, pages = {1 -- 15}, year = {2022}, abstract = {The role of the GMP nucleotides of the bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor of the DMSO reductase family has long been a subject of discussion. The recent characterization of the bis-molybdopterin (bis-Mo-MPT) cofactor present in the E. coli YdhV protein, which differs from bis-MGD solely by the absence of the nucleotides, now enables studying the role of the nucleotides of bis-MGD and bis-MPT cofactors in Moco insertion and the activity of molybdoenzymes in direct comparison. Using the well-known E. coli TMAO reductase TorA as a model enzyme for cofactor insertion, we were able to show that the GMP nucleotides of bis-MGD are crucial for the insertion of the bis-MGD cofactor into apo-TorA.}, language = {en} } @inproceedings{ReimerAharonianHintonetal.2007, author = {Reimer, O. and Aharonian, Felix A. and Hinton, J. and Hofmann, W. and Hoppe, S. and Raue, M. and Reimer, A.}, title = {VHE gamma-rays from Westerlund 2 and implications for the inferred energetics}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18172}, year = {2007}, abstract = {The H.E.S.S. collaboration recently reported the discovery of VHE γ-ray emission coincident with the young stellar cluster Westerlund 2. This system is known to host a population of hot, massive stars, and, most particularly, the WR binary WR 20a. Particle acceleration to TeV energies in Westerlund 2 can be accomplished in several alternative scenarios, therefore we only discuss energetic constraints based on the total available kinetic energy in the system, the actual mass loss rates of respective cluster members, and implied gamma-ray production from processes such as inverse Compton scattering or neutral pion decay. From the inferred gammaray luminosity of the order of 1035erg/s, implications for the efficiency of converting available kinetic energy into non-thermal radiation associated with stellar winds in the Westerlund 2 cluster are discussed under consideration of either the presence or absence of wind clumping.}, language = {en} } @article{WeithoffBell2022, author = {Weithoff, Guntram and Bell, Elanor Margaret}, title = {Complex Trophic Interactions in an Acidophilic Microbial Community}, series = {Microorganisms}, volume = {10}, journal = {Microorganisms}, edition = {7}, publisher = {MDPI}, address = {Basel, Schweiz}, issn = {2076-2607}, doi = {10.3390/microorganisms10071340}, pages = {1 -- 10}, year = {2022}, abstract = {Extreme habitats often harbor specific communities that differ substantially from non-extreme habitats. In many cases, these communities are characterized by archaea, bacteria and protists, whereas the number of species of metazoa and higher plants is relatively low. In extremely acidic habitats, mostly prokaryotes and protists thrive, and only very few metazoa thrive, for example, rotifers. Since many studies have investigated the physiology and ecology of individual species, there is still a gap in research on direct, trophic interactions among extremophiles. To fill this gap, we experimentally studied the trophic interactions between a predatory protist (Actinophrys sol, Heliozoa) and its prey, the rotifers Elosa woralli and Cephalodella sp., the ciliate Urosomoida sp. and the mixotrophic protist Chlamydomonas acidophila (a green phytoflagellate, Chlorophyta). We found substantial predation pressure on all animal prey. High densities of Chlamydomonas acidophila reduced the predation impact on the rotifers by interfering with the feeding behaviour of A. sol. These trophic relations represent a natural case of intraguild predation, with Chlamydomonas acidophila being the common prey and the rotifers/ciliate and A. sol being the intraguild prey and predator, respectively. We further studied this intraguild predation along a resource gradient using Cephalodella sp. as the intraguild prey. The interactions among the three species led to an increase in relative rotifer abundance with increasing resource (Chlamydomonas) densities. By applying a series of laboratory experiments, we revealed the complexity of trophic interactions within a natural extremophilic community.}, language = {en} } @book{WeissVerlaanVasquezCarruthersetal.2022, author = {Weiß, Norman and Verlaan, Stephanie and Vasquez Carruthers, Juan Francisco and Mair, Theresa and Conner, Sean and Maaser, Lucas and R{\"o}thlisberger, Livia}, title = {Transitional Justice}, series = {Potsdamer Studien zu Staat, Recht und Politik}, journal = {Potsdamer Studien zu Staat, Recht und Politik}, number = {7}, editor = {Weiß, Norman}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-473-9}, issn = {1869-2443}, doi = {10.25932/publishup-43171}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-431711}, publisher = {Universit{\"a}t Potsdam}, pages = {194}, year = {2022}, abstract = {This publication deals with the topic of transitional justice. In six case studies, the authors link theoretical and practical implications in order to develop some innovative approaches. Their proposals might help to deal more effectively with the transition of societies, legal orders and political systems. Young academics from various backgrounds provide fresh insights and demonstrate the relevance of the topic. The chapters analyse transitions and conflicts in Sierra Leone, Argentina, Nicaragua, Nepal, and South Sudan as well as Germany's colonial genocide in Namibia. Thus, the book provides the reader with new insights and contributes to the ongoing debate about transitional justice.}, language = {en} } @article{PrasseIversenLienhardetal.2022, author = {Prasse, Paul and Iversen, Pascal and Lienhard, Matthias and Thedinga, Kristina and Herwig, Ralf and Scheffer, Tobias}, title = {Pre-Training on In Vitro and Fine-Tuning on Patient-Derived Data Improves Deep Neural Networks for Anti-Cancer Drug-Sensitivity Prediction}, series = {MDPI}, volume = {14}, journal = {MDPI}, edition = {16}, publisher = {MDPI}, address = {Basel, Schweiz}, issn = {2072-6694}, doi = {10.3390/cancers14163950}, pages = {1 -- 14}, year = {2022}, abstract = {Large-scale databases that report the inhibitory capacities of many combinations of candidate drug compounds and cultivated cancer cell lines have driven the development of preclinical drug-sensitivity models based on machine learning. However, cultivated cell lines have devolved from human cancer cells over years or even decades under selective pressure in culture conditions. Moreover, models that have been trained on in vitro data cannot account for interactions with other types of cells. Drug-response data that are based on patient-derived cell cultures, xenografts, and organoids, on the other hand, are not available in the quantities that are needed to train high-capacity machine-learning models. We found that pre-training deep neural network models of drug sensitivity on in vitro drug-sensitivity databases before fine-tuning the model parameters on patient-derived data improves the models' accuracy and improves the biological plausibility of the features, compared to training only on patient-derived data. From our experiments, we can conclude that pre-trained models outperform models that have been trained on the target domains in the vast majority of cases.}, language = {en} } @article{OmaneHoehle2020, author = {Omane, Paul Okyere and H{\"o}hle, Barbara}, title = {Acquiring syntactic variability}, series = {Frontiers in communication}, volume = {2021}, journal = {Frontiers in communication}, publisher = {Frontiers Media}, address = {Lausanne, Schweiz}, issn = {2297-900X}, doi = {10.3389/fcomm.2021.604951}, pages = {15}, year = {2020}, abstract = {This paper investigates the predictions of the Derivational Complexity Hypothesis by studying the acquisition of wh-questions in 4- and 5-year-old Akan-speaking children in an experimental approach using an elicited production and an elicited imitation task. Akan has two types of wh-question structures (wh-in-situ and wh-ex-situ questions), which allows an investigation of children's acquisition of these two question structures and their preferences for one or the other. Our results show that adults prefer to use wh-ex-situ questions over wh-in-situ questions. The results from the children show that both age groups have the two question structures in their linguistic repertoire. However, they differ in their preferences in usage in the elicited production task: while the 5-year-olds preferred the wh-in-situ structure over the wh-ex-situ structure, the 4-year-olds showed a selective preference for the wh-in-situ structure in who-questions. These findings suggest a developmental change in wh-question preferences in Akan-learning children between 4 and 5 years of age with a so far unobserved u-shaped developmental pattern. In the elicited imitation task, all groups showed a strong tendency to maintain the structure of in-situ and ex-situ questions in repeating grammatical questions. When repairing ungrammatical ex-situ questions, structural changes to grammatical in-situ questions were hardly observed but the insertion of missing morphemes while keeping the ex-situ structure. Together, our findings provide only partial support for the Derivational Complexity Hypothesis.}, language = {en} } @phdthesis{Mueller2008, author = {M{\"u}ller, Melanie J. I.}, title = {Bidirectional transport by molecular motors}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18715}, school = {Universit{\"a}t Potsdam}, year = {2008}, abstract = {In biological cells, the long-range intracellular traffic is powered by molecular motors which transport various cargos along microtubule filaments. The microtubules possess an intrinsic direction, having a 'plus' and a 'minus' end. Some molecular motors such as cytoplasmic dynein walk to the minus end, while others such as conventional kinesin walk to the plus end. Cells typically have an isopolar microtubule network. This is most pronounced in neuronal axons or fungal hyphae. In these long and thin tubular protrusions, the microtubules are arranged parallel to the tube axis with the minus ends pointing to the cell body and the plus ends pointing to the tip. In such a tubular compartment, transport by only one motor type leads to 'motor traffic jams'. Kinesin-driven cargos accumulate at the tip, while dynein-driven cargos accumulate near the cell body. We identify the relevant length scales and characterize the jamming behaviour in these tube geometries by using both Monte Carlo simulations and analytical calculations. A possible solution to this jamming problem is to transport cargos with a team of plus and a team of minus motors simultaneously, so that they can travel bidirectionally, as observed in cells. The presumably simplest mechanism for such bidirectional transport is provided by a 'tug-of-war' between the two motor teams which is governed by mechanical motor interactions only. We develop a stochastic tug-of-war model and study it with numerical and analytical calculations. We find a surprisingly complex cooperative motility behaviour. We compare our results to the available experimental data, which we reproduce qualitatively and quantitatively.}, language = {en} } @article{RoseGroegerHoelzle2021, author = {Rose, Robert and Groeger, Lars and H{\"o}lzle, Katharina}, title = {The Emergence of Shared Leadership in Innovation Labs}, series = {Frontiers in Psychology}, volume = {12}, journal = {Frontiers in Psychology}, publisher = {Frontiers in psychology}, address = {Lausanne, Schweiz}, issn = {1664-1078}, doi = {10.3389/fpsyg.2021.685167}, pages = {1 -- 13}, year = {2021}, abstract = {Implementing innovation laboratories to leverage intrapreneurship are an increasingly popular organizational practice. A typical feature in these creative environments are semi-autonomous teams in which multiple members collectively exert leadership influence, thereby challenging traditional command-and-control conceptions of leadership. An extensive body of research on the team-centric concept of shared leadership has recognized the potential for pluralized leadership structures in enhancing team effectiveness; however, little empirical work has been conducted in organizational contexts in which creativity is key. This study set out to explore antecedents of shared leadership and its influence on team creativity in an innovation lab. Building on extant shared leadership and innovation research, we propose antecedents customary to creative teamwork, that is, experimental culture, task reflexivity, and voice. Multisource data were collected from 104 team members and 49 evaluations of 29 coaches nested in 21 teams working in a prototypical innovation lab. We identify factors specific to creative teamwork that facilitate the emergence of shared leadership by providing room for experimentation, encouraging team members to speak up in the creative process, and cultivating a reflective application of entrepreneurial thinking. We provide specific exemplary activities for innovation lab teams to increase levels of shared leadership.}, language = {en} } @article{DordevicHoelzerRussoetal.2022, author = {Dordevic, Milos and H{\"o}lzer, Sonja and Russo, Augusta and Garc{\´i}a Alanis, Jos{\´e} Carlos and M{\"u}ller, Notger Germar}, title = {The Role of the Precuneus in Human Spatial Updating in a Real Environment Setting—A cTBS Study}, series = {Life}, volume = {12}, journal = {Life}, edition = {8}, publisher = {MDPI}, address = {Basel, Schweiz}, issn = {2075-1729}, doi = {10.3390/life12081239}, pages = {1 -- 13}, year = {2022}, abstract = {As we move through an environment, we update positions of our body relative to other objects, even when some objects temporarily or permanently leave our field of view—this ability is termed egocentric spatial updating and plays an important role in everyday life. Still, our knowledge about its representation in the brain is still scarce, with previous studies using virtual movements in virtual environments or patients with brain lesions suggesting that the precuneus might play an important role. However, whether this assumption is also true when healthy humans move in real environments where full body-based cues are available in addition to the visual cues typically used in many VR studies is unclear. Therefore, in this study we investigated the role of the precuneus in egocentric spatial updating in a real environment setting in 20 healthy young participants who underwent two conditions in a cross-over design: (a) stimulation, achieved through applying continuous theta-burst stimulation (cTBS) to inhibit the precuneus and (b) sham condition (activated coil turned upside down). In both conditions, participants had to walk back with blindfolded eyes to objects they had previously memorized while walking with open eyes. Simplified trials (without spatial updating) were used as control condition, to make sure the participants were not affected by factors such as walking blindfolded, vestibular or working memory deficits. A significant interaction was found, with participants performing better in the sham condition compared to real stimulation, showing smaller errors both in distance and angle. The results of our study reveal evidence of an important role of the precuneus in a real-environment egocentric spatial updating; studies on larger samples are necessary to confirm and further investigate this finding.}, language = {en} } @article{WestphalKalinowskiHoferichteretal.2022, author = {Westphal, Andrea and Kalinowski, Eva and Hoferichter, Clara Josepha and Vock, Miriam}, title = {K-12 teachers' stress and burnout during the COVID-19 pandemic: A systematic review}, series = {Frontiers in Psychology}, journal = {Frontiers in Psychology}, publisher = {Frontiers}, address = {Lausanne, Schweiz}, issn = {1664-1078}, doi = {10.3389/fpsyg.2022.920326}, pages = {1 -- 29}, year = {2022}, abstract = {We present the first systematic literature review on stress and burnout in K-12 teachers during the COVID-19 pandemic. Based on a systematic literature search, we identified 17 studies that included 9,874 K-12 teachers from around the world. These studies showed some indication that burnout did increase during the COVID-19 pandemic. There were, however, almost no differences in the levels of stress and burnout experienced by K-12 teachers compared to individuals employed in other occupational fields. School principals' leadership styles emerged as an organizational characteristic that is highly relevant for K-12 teachers' levels of stress and burnout. Individual teacher characteristics associated with burnout were K-12 teachers' personality, self-efficacy in online teaching, and perceived vulnerability to COVID-19. In order to reduce stress, there was an indication that stress-management training in combination with training in technology use for teaching may be superior to stress-management training alone. Future research needs to adopt more longitudinal designs and examine the interplay between individual and organizational characteristics in the development of teacher stress and burnout during the COVID-19 pandemic and beyond.}, language = {en} }