TY - JOUR A1 - Plue, Jan A1 - De Frenne, Pieter A1 - Acharya, Kamal A1 - Brunet, Jörg A1 - Chabrerie, Olivier A1 - Decocq, Guillaume A1 - Diekmann, Martin A1 - Graae, Bente J. A1 - Heinken, Thilo A1 - Hermy, Martin A1 - Kolb, Annette A1 - Lemke, Isgard A1 - Liira, Jaan A1 - Naaf, Tobias A1 - Verheyen, Kris A1 - Wulf, Monika A1 - Cousins, Sara A. O. T1 - Where does the community start, and where does it end? BT - including the seed bank to reassess forest herb layer responses to the environment JF - Journal of vegetation science N2 - QuestionBelow-ground processes are key determinants of above-ground plant population and community dynamics. Still, our understanding of how environmental drivers shape plant communities is mostly based on above-ground diversity patterns, bypassing below-ground plant diversity stored in seed banks. As seed banks may shape above-ground plant communities, we question whether concurrently analysing the above- and below-ground species assemblages may potentially enhance our understanding of community responses to environmental variation. LocationTemperate deciduous forests along a 2000km latitudinal gradient in NW Europe. MethodsHerb layer, seed bank and local environmental data including soil pH, canopy cover, forest cover continuity and time since last canopy disturbance were collected in 129 temperate deciduous forest plots. We quantified herb layer and seed bank diversity per plot and evaluated how environmental variation structured community diversity in the herb layer, seed bank and the combined herb layer-seed bank community. ResultsSeed banks consistently held more plant species than the herb layer. How local plot diversity was partitioned across the herb layer and seed bank was mediated by environmental variation in drivers serving as proxies of light availability. The herb layer and seed bank contained an ever smaller and ever larger share of local diversity, respectively, as both canopy cover and time since last canopy disturbance decreased. Species richness and -diversity of the combined herb layer-seed bank community responded distinctly differently compared to the separate assemblages in response to environmental variation in, e.g. forest cover continuity and canopy cover. ConclusionsThe seed bank is a below-ground diversity reservoir of the herbaceous forest community, which interacts with the herb layer, although constrained by environmental variation in e.g. light availability. The herb layer and seed bank co-exist as a single community by means of the so-called storage effect, resulting in distinct responses to environmental variation not necessarily recorded in the individual herb layer or seed bank assemblages. Thus, concurrently analysing above- and below-ground diversity will improve our ecological understanding of how understorey plant communities respond to environmental variation. KW - Above-ground KW - Below-ground KW - Canopy KW - Disturbance KW - Diversity KW - Light availability KW - NWEurope KW - Plant community KW - Species co-existence KW - Storage effect Y1 - 2017 U6 - https://doi.org/10.1111/jvs.12493 SN - 1100-9233 SN - 1654-1103 VL - 28 IS - 2 SP - 424 EP - 435 PB - Wiley CY - Hoboken ER - TY - GEN A1 - Henze, Andrea A1 - Raila, Jens A1 - Kempf, Caroline A1 - Reinke, Petra A1 - Sefrin, Anett A1 - Querfeld, Uwe A1 - Schweigert, Florian J. T1 - Vitamin A metabolism is changed in donors after living-kidney transplantation BT - an observational study N2 - Background The kidneys are essential for the metabolism of vitamin A (retinol) and its transport proteins retinol-binding protein 4 (RBP4) and transthyretin. Little is known about changes in serum concentration after living donor kidney transplantation (LDKT) as a consequence of unilateral nephrectomy; although an association of these parameters with the risk of cardiovascular diseases and insulin resistance has been suggested. Therefore we analyzed the concentration of retinol, RBP4, apoRBP4 and transthyretin in serum of 20 living-kidney donors and respective recipients at baseline as well as 6 weeks and 6 months after LDKT. Results As a consequence of LDKT, the kidney function of recipients was improved while the kidney function of donors was moderately reduced within 6 weeks after LDKT. With regard to vitamin A metabolism, the recipients revealed higher levels of retinol, RBP4, transthyretin and apoRBP4 before LDKT in comparison to donors. After LDKT, the levels of all four parameters decreased in serum of the recipients, while retinol, RBP4 as well as apoRBP4 serum levels of donors increased and remained increased during the follow-up period of 6 months. Conclusion LDKT is generally regarded as beneficial for allograft recipients and not particularly detrimental for the donors. However, it could be demonstrated in this study that a moderate reduction of kidney function by unilateral nephrectomy, resulted in an imbalance of components of vitamin A metabolism with a significant increase of retinol and RBP4 and apoRBP4 concentration in serum of donors. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 373 KW - Donors KW - glomerular filtration rate KW - kidney transplantation KW - retinol KW - retinol-binding protein 4 KW - transthyretin Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400942 ER - TY - JOUR A1 - Koc-Januchta, Marta A1 - Höffler, Tim A1 - Thoma, Gun-Brit A1 - Prechtl, Helmut A1 - Leutner, Detlev T1 - Visualizers versus verbalizers BT - Effects of cognitive style on learning with texts and pictures - An eye-tracking study JF - Computers in human behavior N2 - This study was conducted in order to examine the differences between visualizers and verbalizers in the way they gaze at pictures and texts while learning. Using a collection of questionnaires, college students were classified according to their visual or verbal cognitive style and were asked to learn about two different, in terms of subject and type of knowledge, topics by means of text-picture combinations. Eye-tracking was used to investigate their gaze behavior. The results show that visualizers spent significantly more time inspecting pictures than verbalizers, while verbalizers spent more time inspecting texts. Results also suggest that both visualizers' and verbalizers' way of learning is active but mostly within areas providing the source of information in line with their cognitive style (pictures or text). Verbalizers tended to enter non-informative, irrelevant areas of pictures sooner than visualizers. The comparison of learning outcomes showed that the group of visualizers achieved better results than the group of verbalizers on a comprehension test. KW - Cognitive style KW - Verbalizer KW - Visualizer KW - Eye-tracking KW - Multimedia learning Y1 - 2016 U6 - https://doi.org/10.1016/j.chb.2016.11.028 SN - 0747-5632 SN - 1873-7692 VL - 68 SP - 170 EP - 179 PB - Elsevier CY - Oxford ER - TY - THES A1 - Yang, Lei T1 - Verification of systemic mRNAs mobility and mobile functions Y1 - 2017 ER - TY - JOUR A1 - Reil, Daniela A1 - Imholt, Christian A1 - Rosenfeld, Ulrike M. A1 - Drewes, Stephan A1 - Fischer, S. A1 - Heuser, Emil A1 - Petraityte-Burneikiene, Rasa A1 - Ulrich, R. G. A1 - Jacob, J. T1 - Validation of the Puumala virus rapid field test for bank voles in Germany JF - Epidemiology and infection N2 - Puumala virus (PUUV) causes many human infections in large parts of Europe and can lead to mild to moderate disease. The bank vole (Myodes glareolus) is the only reservoir of PUUV in Central Europe. A commercial PUUV rapid field test for rodents was validated for bank-vole blood samples collected in two PUUV-endemic regions in Germany (North Rhine-Westphalia and Baden-Wurttemberg). A comparison of the results of the rapid field test and standard ELISAs indicated a test efficacy of 93-95%, largely independent of the origin of the antigens used in the ELISA. In ELISAs, reactivity for the German PUUV strain was higher compared to the Swedish strain but not compared to the Finnish strain, which was used for the rapid field test. In conclusion, the use of the rapid field test can facilitate short-term estimation of PUUV seroprevalence in bank-vole populations in Germany and can aid in assessing human PUUV infection risk. KW - Antibody detection KW - early warning KW - Europe KW - hantavirus KW - Myodes glareolus Y1 - 2017 U6 - https://doi.org/10.1017/S0950268816002557 SN - 0950-2688 SN - 1469-4409 VL - 145 IS - 3 SP - 434 EP - 439 PB - Cambridge Univ. Press CY - New York ER - TY - THES A1 - Sedaghatmehr, Mastoureh T1 - Unraveling the regulatory mechanisms of heat stress memory in Arabidopsis thaliana Y1 - 2017 ER - TY - GEN A1 - Hempel, Sabrina A1 - Koseska, Aneta A1 - Nikoloski, Zoran A1 - Kurths, Jürgen T1 - Unraveling gene regulatory networks from time-resolved gene expression data BT - a measures comparison study N2 - Background: Inferring regulatory interactions between genes from transcriptomics time-resolved data, yielding reverse engineered gene regulatory networks, is of paramount importance to systems biology and bioinformatics studies. Accurate methods to address this problem can ultimately provide a deeper insight into the complexity, behavior, and functions of the underlying biological systems. However, the large number of interacting genes coupled with short and often noisy time-resolved read-outs of the system renders the reverse engineering a challenging task. Therefore, the development and assessment of methods which are computationally efficient, robust against noise, applicable to short time series data, and preferably capable of reconstructing the directionality of the regulatory interactions remains a pressing research problem with valuable applications. Results: Here we perform the largest systematic analysis of a set of similarity measures and scoring schemes within the scope of the relevance network approach which are commonly used for gene regulatory network reconstruction from time series data. In addition, we define and analyze several novel measures and schemes which are particularly suitable for short transcriptomics time series. We also compare the considered 21 measures and 6 scoring schemes according to their ability to correctly reconstruct such networks from short time series data by calculating summary statistics based on the corresponding specificity and sensitivity. Our results demonstrate that rank and symbol based measures have the highest performance in inferring regulatory interactions. In addition, the proposed scoring scheme by asymmetric weighting has shown to be valuable in reducing the number of false positive interactions. On the other hand, Granger causality as well as information-theoretic measures, frequently used in inference of regulatory networks, show low performance on the short time series analyzed in this study. Conclusions: Our study is intended to serve as a guide for choosing a particular combination of similarity measures and scoring schemes suitable for reconstruction of gene regulatory networks from short time series data. We show that further improvement of algorithms for reverse engineering can be obtained if one considers measures that are rooted in the study of symbolic dynamics or ranks, in contrast to the application of common similarity measures which do not consider the temporal character of the employed data. Moreover, we establish that the asymmetric weighting scoring scheme together with symbol based measures (for low noise level) and rank based measures (for high noise level) are the most suitable choices. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 371 KW - unferring cellular networks KW - mutual information KW - Escherichia-coli KW - cluster-analysis KW - series KW - algorithms KW - inference KW - models KW - recognition KW - variables Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400924 ER - TY - THES A1 - Weiß, Lina T1 - Understanding the emergence and maintenance of biodiversity in grasslands BT - linking individual plant responses to community patterns Y1 - 2017 ER - TY - JOUR A1 - Kehlmaier, Christian A1 - Barlow, Axel A1 - Hastings, Alexander K. A1 - Vamberger, Melita A1 - Paijmans, Johanna L. A. A1 - Steadman, David W. A1 - Albury, Nancy A. A1 - Franz, Richard A1 - Hofreiter, Michael A1 - Fritz, Uwe T1 - Tropical ancient DNA reveals relationships of the extinct bahamian giant tortoise Chelonoidis alburyorum JF - Proceedings of the Royal Society of London : Series B, Biological sciences N2 - Ancient DNA of extinct species from the Pleistocene and Holocene has provided valuable evolutionary insights. However, these are largely restricted to mammals and high latitudes because DNA preservation in warm climates is typically poor. In the tropics and subtropics, non-avian reptiles constitute a significant part of the fauna and little is known about the genetics of the many extinct reptiles from tropical islands. We have reconstructed the near-complete mitochondrial genome of an extinct giant tortoise from the Bahamas (Chelonoidis alburyorum) using an approximately 1000-year-old humerus from a water-filled sinkhole (blue hole) on Great Abaco Island. Phylogenetic and molecular clock analyses place this extinct species as closely related to Galapagos (C. niger complex) and Chaco tortoises (C. chilensis), and provide evidence for repeated overseas dispersal in this tortoise group. The ancestors of extant Chelonoidis species arrived in South America from Africa only after the opening of the Atlantic Ocean and dispersed from there to the Caribbean and the Galapagos Islands. Our results also suggest that the anoxic, thermally buffered environment of blue holes may enhance DNA preservation, and thus are opening a window for better understanding evolution and population history of extinct tropical species, which would likely still exist without human impact. KW - Bahamas KW - biogeography KW - extinction KW - palaeontology KW - phylogeny Y1 - 2017 U6 - https://doi.org/10.1098/rspb.2016.2235 SN - 0962-8452 SN - 1471-2954 VL - 284 PB - The Royal Society CY - London ER - TY - JOUR A1 - Rojas-Jimenez, Keilor A1 - Fonvielle, Jeremy Andre A1 - Ma, Hua A1 - Grossart, Hans-Peter T1 - Transformation of humic substances by the freshwater Ascomycete Cladosporium sp. JF - Waterbird N2 - The ecological relevance of fungi in freshwater ecosystems is becoming increasingly evident, particularly in processing the extensive amounts of polymeric organic carbon such as cellulose, chitin, and humic substances (HS). We isolated several fungal strains from oligo-mesotrophic Lake Stechlin, Brandenburg, Germany, and analyzed their ability to degrade polymeric-like substrates. Using liquid chromatography-organic carbon detection, we determined the byproducts of HS transformation by the freshwater fungus Cladosporium sp. KR14. We demonstrate the ability of this fungus to degrade and simultaneously synthesize HS, and that transformation processes were intensified when iron, as indicator of the occurrence of Fenton reactions, was present in the medium. Furthermore, we showed that structural complexity of the HS produced changed with the availability of other polymeric substances in the medium. Our study highlights the contribution of freshwater Ascomycetes to the transformation of complex organic compounds. As such, it has important implications for understanding the ecological contribution of fungi to aquatic food webs and related biogeochemical cycles. Y1 - 2017 U6 - https://doi.org/10.1002/lno.10545 SN - 1524-4695 SN - 1938-5390 VL - 40 SP - 282 EP - 288 PB - Waterbird SOC CY - Washington ER -