@article{SobhkhizMiandehiYamazakiArrasetal.2022, author = {Sobhkhiz-Miandehi, Sahar and Yamazaki, Yosuke and Arras, Christina and Miyoshi, Yasunobu and Shinagawa, Hiroyuki}, title = {Comparison of the tidal signatures in sporadic E and vertical ion convergence rate, using FORMOSAT-3/COSMIC radio occultation observations and GAIA model}, series = {Earth, planets and space : EPS}, volume = {74}, journal = {Earth, planets and space : EPS}, number = {1}, publisher = {Springer}, address = {Heidelberg}, issn = {1880-5981}, doi = {10.1186/s40623-022-01637-y}, pages = {13}, year = {2022}, abstract = {Sporadic E or Es is a transient phenomenon where thin layers of enhanced electron density appear in the ionospheric E region (90-120 km altitude). The neutral wind shear caused by atmospheric tides can lead ions to converge vertically at E-region heights and form the Es layer. This research aims to determine the role of atmospheric solar and lunar tides in Es occurrence. For this purpose, radio occultation data of FORMOSAT-3/COSMIC have been used, which provide complete global coverage of Es events. Moreover, GAIA model simulations have been employed to evaluate the vertical ion convergence induced by solar tides. The results show both migrating and non-migrating solar tidal signatures and the semidiurnal migrating lunar tidal signature mainly in low and mid-latitude Es occurrence. The seasonal variation of the migrating solar tidal components of Es is in good agreement with those in the vertical ion convergence derived from GAIA at higher altitudes. Furthermore, some non-migrating components of solar tides, including semidiurnal westward wavenumbers 1 and 3 and diurnal eastward wavenumbers 2 and 3, also significantly affect the Es occurrence rate.}, language = {en} } @article{GhafarianWielandLuettschwageretal.2022, author = {Ghafarian, Fatemeh and Wieland, Ralf and L{\"u}ttschwager, Dietmar and Nendel, Claas}, title = {Application of extreme gradient boosting and Shapley Additive explanations to predict temperature regimes inside forests from standard open-field meteorological data}, series = {Environmental modelling \& software with environment data news}, volume = {156}, journal = {Environmental modelling \& software with environment data news}, publisher = {Elsevier}, address = {Oxford}, issn = {1364-8152}, doi = {10.1016/j.envsoft.2022.105466}, pages = {11}, year = {2022}, abstract = {Forest microclimate can buffer biotic responses to summer heat waves, which are expected to become more extreme under climate warming. Prediction of forest microclimate is limited because meteorological observation standards seldom include situations inside forests. We use eXtreme Gradient Boosting - a Machine Learning technique - to predict the microclimate of forest sites in Brandenburg, Germany, using seasonal data comprising weather features. The analysis was amended by applying a SHapley Additive explanation to show the interaction effect of variables and individualised feature attributions. We evaluate model performance in comparison to artificial neural networks, random forest, support vector machine, and multi-linear regression. After implementing a feature selection, an ensemble approach was applied to combine individual models for each forest and improve robustness over a given single prediction model. The resulting model can be applied to translate climate change scenarios into temperatures inside forests to assess temperature-related ecosystem services provided by forests.}, language = {en} } @misc{OlayideLargeStridhetal.2020, author = {Olayide, Priscilla and Large, Annabel and Stridh, Linnea and Rabbi, Ismail and Baldermann, Susanne and Stavolone, Livia and Alexandersson, Erik}, title = {Gene expression and metabolite profiling of thirteen Nigerian cassava landraces to elucidate starch and carotenoid composition}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {3}, issn = {1866-8372}, doi = {10.25932/publishup-51783}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-517834}, pages = {18}, year = {2020}, abstract = {The prevalence of vitamin A deficiency in sub-Saharan Africa necessitates effective approaches to improve provitamin A content of major staple crops. Cassava holds much promise for food security in sub-Saharan Africa, but a negative correlation between beta-carotene, a provitamin A carotenoid, and dry matter content has been reported, which poses a challenge to cassava biofortification by conventional breeding. To identify suitable material for genetic transformation in tissue culture with the overall aim to increase beta-carotene and maintain starch content as well as better understand carotenoid composition, root and leaf tissues from thirteen field-grown cassava landraces were analyzed for agronomic traits, carotenoid, chlorophyll, and starch content. The expression of five genes related to carotenoid biosynthesis were determined in selected landraces. Analysis revealed a weak negative correlation between starch and beta-carotene content, whereas there was a strong positive correlation between root yield and many carotenoids including beta-carotene. Carotenoid synthesis genes were expressed in both white and yellow cassava roots, but phytoene synthase 2 (PSY2), lycopene-epsilon-cyclase (LCY epsilon), and beta-carotenoid hydroxylase (CHY beta) expression were generally higher in yellow roots. This study identified lines with reasonably high content of starch and beta-carotene that could be candidates for biofortification by further breeding or plant biotechnological means.}, language = {en} } @article{ArmstrongRadouskyAustinetal.2022, author = {Armstrong, Michael R. and Radousky, Harry B. and Austin, Ryan A. and Tschauner, Oliver and Brown, Shaughnessy and Gleason, Arianna E. and Goldman, Nir and Granados, Eduardo and Grivickas, Paulius and Holtgrewe, Nicholas and Kroonblawd, Matthew P. and Lee, Hae Ja and Lobanov, Sergey and Nagler, Bob and Nam, Inhyuk and Prakapenka, Vitali and Prescher, Clemens and Reed, Evan J. and Stavrou, Elissaios and Walter, Peter and Goncharov, Alexander F. and Belof, Jonathan L.}, title = {Highly ordered graphite (HOPG) to hexagonal diamond (lonsdaleite) phase transition observed on picosecond time scales using ultrafast x-ray diffraction}, series = {Journal of applied physics}, volume = {132}, journal = {Journal of applied physics}, number = {5}, publisher = {AIP Publishing}, address = {Melville}, issn = {0021-8979}, doi = {10.1063/5.0085297}, pages = {10}, year = {2022}, abstract = {The response of rapidly compressed highly oriented pyrolytic graphite (HOPG) normal to its basal plane was investigated at a pressure of \& SIM;80 GPa. Ultrafast x-ray diffraction using \& SIM;100 fs pulses at the Materials Under Extreme Conditions sector of the Linac Coherent Light Source was used to probe the changes in crystal structure resulting from picosecond timescale compression at laser drive energies ranging from 2.5 to 250 mJ. A phase transformation from HOPG to a highly textured hexagonal diamond structure is observed at the highest energy, followed by relaxation to a still highly oriented, but distorted graphite structure following release. We observe the formation of a highly oriented lonsdaleite within 20 ps, subsequent to compression. This suggests that a diffusionless martensitic mechanism may play a fundamental role in phase transition, as speculated in an early work on this system, and more recent static studies of diamonds formed in impact events. Published by AIP Publishing.}, language = {en} } @misc{RianoPachonKleessenNeigenfindetal.2010, author = {Ria{\~n}o-Pach{\´o}n, Diego Mauricio and Kleessen, Sabrina and Neigenfind, Jost and Durek, Pawel and Weber, Elke and Engelsberger, Wolfgang R. and Walther, Dirk and Selbig, Joachim and Schulze, Waltraud X. and Kersten, Birgit}, title = {Proteome-wide survey of phosphorylation patterns affected by nuclear DNA polymorphisms in Arabidopsis thaliana}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1328}, issn = {1866-8372}, doi = {10.25932/publishup-43118}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-431181}, pages = {19}, year = {2010}, abstract = {Background: Protein phosphorylation is an important post-translational modification influencing many aspects of dynamic cellular behavior. Site-specific phosphorylation of amino acid residues serine, threonine, and tyrosine can have profound effects on protein structure, activity, stability, and interaction with other biomolecules. Phosphorylation sites can be affected in diverse ways in members of any species, one such way is through single nucleotide polymorphisms (SNPs). The availability of large numbers of experimentally identified phosphorylation sites, and of natural variation datasets in Arabidopsis thaliana prompted us to analyze the effect of non-synonymous SNPs (nsSNPs) onto phosphorylation sites. Results: From the analyses of 7,178 experimentally identified phosphorylation sites we found that: (i) Proteins with multiple phosphorylation sites occur more often than expected by chance. (ii) Phosphorylation hotspots show a preference to be located outside conserved domains. (iii) nsSNPs affected experimental phosphorylation sites as much as the corresponding non-phosphorylated amino acid residues. (iv) Losses of experimental phosphorylation sites by nsSNPs were identified in 86 A. thaliana proteins, among them receptor proteins were overrepresented. These results were confirmed by similar analyses of predicted phosphorylation sites in A. thaliana. In addition, predicted threonine phosphorylation sites showed a significant enrichment of nsSNPs towards asparagines and a significant depletion of the synonymous substitution. Proteins in which predicted phosphorylation sites were affected by nsSNPs (loss and gain), were determined to be mainly receptor proteins, stress response proteins and proteins involved in nucleotide and protein binding. Proteins involved in metabolism, catalytic activity and biosynthesis were less affected. Conclusions: We analyzed more than 7,100 experimentally identified phosphorylation sites in almost 4,300 protein-coding loci in silico, thus constituting the largest phosphoproteomics dataset for A. thaliana available to date. Our findings suggest a relatively high variability in the presence or absence of phosphorylation sites between different natural accessions in receptor and other proteins involved in signal transduction. Elucidating the effect of phosphorylation sites affected by nsSNPs on adaptive responses represents an exciting research goal for the future.}, language = {en} } @article{NagelKirschbaumEngelmannetal.2018, author = {Nagel, Rebecca and Kirschbaum, Frank and Engelmann, Jacob and Hofmann, Volker and Pawelzik, Felix and Tiedemann, Ralph}, title = {Male-mediated species recognition among African weakly electric fishes}, series = {Royal Society Open Science}, volume = {5}, journal = {Royal Society Open Science}, number = {2}, publisher = {Royal Society}, address = {London}, issn = {2054-5703}, doi = {10.1098/rsos.170443}, pages = {8}, year = {2018}, abstract = {Effective communication among sympatric species is often instrumental for behavioural isolation, where the failure to successfully discriminate between potential mates could lead to less fit hybrid offspring. Discrimination between con- and heterospecifics tends to occur more often in the sex that invests more in offspring production, i.e. females, but males may also mediate reproductive isolation. In this study, we show that among two Campylomormyrus Africanweakly electric fish species, males preferentially associate with conspecific females during choice tests using live fish as stimuli, i.e. when all sensory modalities potentially used for communication were present. We then conducted playback experiments to determine whether the species-specific electric organ discharge (EOD) used for electrocommunication serves as the cue for this conspecific association preference. Interestingly, only C. compressirostris males associated significantly more with the conspecific EOD waveform when playback stimuli were provided, while no such association preference was observed in C. tamandua males. Given our results, the EOD appears to serve, in part, as a male-mediated pre-zygotic isolation mechanism among sympatric species. However, the failure of C. tamandua males to discriminate between con- and heterospecific playback discharges suggests that multiple modalities may be necessary for species recognition in some African weakly electric fish species.}, language = {en} } @article{MareljaLeimkuehlerMissirlis2018, author = {Marelja, Zvonimir and Leimk{\"u}hler, Silke and Missirlis, Fanis}, title = {Iron sulfur and molybdenum cofactor enzymes regulate the drosophila life cycle by controlling cell metabolism}, series = {Frontiers in physiology}, volume = {9}, journal = {Frontiers in physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2018.00050}, pages = {31}, year = {2018}, abstract = {Iron sulfur (Fe-S) clusters and the molybdenum cofactor (Moco) are present at enzyme sites, where the active metal facilitates electron transfer. Such enzyme systems are soluble in the mitochondrial matrix, cytosol and nucleus, or embedded in the inner mitochondrial membrane, but virtually absent from the cell secretory pathway. They are of ancient evolutionary origin supporting respiration, DNA replication, transcription, translation, the biosynthesis of steroids, heme, catabolism of purines, hydroxylation of xenobiotics, and cellular sulfur metabolism. Here, Fe-S cluster and Moco biosynthesis in Drosophila melanogaster is reviewed and the multiple biochemical and physiological functions of known Fe-S and Moco enzymes are described. We show that RNA interference of Mocs3 disrupts Moco biosynthesis and the circadian clock. Fe-S-dependent mitochondrial respiration is discussed in the context of germ line and somatic development, stem cell differentiation and aging. The subcellular compartmentalization of the Fe-S and Moco assembly machinery components and their connections to iron sensing mechanisms and intermediary metabolism are emphasized. A biochemically active Fe-S core complex of heterologously expressed fly Nfs1, Isd11, IscU, and human frataxin is presented. Based on the recent demonstration that copper displaces the Fe-S cluster of yeast and human ferredoxin, an explanation for why high dietary copper leads to cytoplasmic iron deficiency in flies is proposed. Another proposal that exosomes contribute to the transport of xanthine dehydrogenase from peripheral tissues to the eye pigment cells is put forward, where the Vps16a subunit of the HOPS complex may have a specialized role in concentrating this enzyme within pigment granules. Finally, we formulate a hypothesis that (i) mitochondrial superoxide mobilizes iron from the Fe-S clusters in aconitase and succinate dehydrogenase; (ii) increased iron transiently displaces manganese on superoxide dismutase, which may function as a mitochondrial iron sensor since it is inactivated by iron; (iii) with the Krebs cycle thus disrupted, citrate is exported to the cytosol for fatty acid synthesis, while succinyl-CoA and the iron are used for heme biosynthesis; (iv) as iron is used for heme biosynthesis its concentration in the matrix drops allowing for manganese to reactivate superoxide dismutase and Fe-S cluster biosynthesis to reestablish the Krebs cycle.}, language = {en} } @article{NizardoSchanzenbachSchoenemannetal.2018, author = {Nizardo, Noverra M. and Schanzenbach, Dirk and Sch{\"o}nemann, Eric and Laschewsky, Andre}, title = {Exploring poly(ethylene glycol)-polyzwitterion diblock copolymers as biocompatible smart macrosurfactants featuring UCST-phase behavior in normal saline solution}, series = {Polymers}, volume = {10}, journal = {Polymers}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2073-4360}, doi = {10.3390/polym10030325}, pages = {22}, year = {2018}, abstract = {Nonionic-zwitterionic diblock copolymers are designed to feature a coil-to-globule collapse transition with an upper critical solution temperature (UCST) in aqueous media, including physiological saline solution. The block copolymers that combine presumably highly biocompatible blocks are synthesized by chain extension of a poly(ethylene glycol) (PEG) macroinitiator via atom transfer radical polymerization (ATRP) of sulfobetaine and sulfabetaine methacrylates. Their thermoresponsive behavior is studied by variable temperature turbidimetry and H-1 NMR spectroscopy. While the polymers with polysulfobetaine blocks exhibit phase transitions in the physiologically interesting window of 30-50 degrees C only in pure aqueous solution, the polymers bearing polysulfabetaine blocks enabled phase transitions only in physiological saline solution. By copolymerizing a pair of structurally closely related sulfo-and sulfabetaine monomers, thermoresponsive behavior can be implemented in aqueous solutions of both low and high salinity. Surprisingly, the presence of the PEG blocks can affect the UCST-transitions of the polyzwitterions notably. In specific cases, this results in "schizophrenic" thermoresponsive behavior displaying simultaneously an UCST and an LCST (lower critical solution temperature) transition. Exploratory experiments on the UCST-transition triggered the encapsulation and release of various solvatochromic fluorescent dyes as model "cargos" failed, apparently due to the poor affinity even of charged organic compounds to the collapsed state of the polyzwitterions.}, language = {en} } @article{TopcuFruehwirthMoseretal.2018, author = {Top{\c{c}}u, {\c{C}}ağda{\c{s}} and Fr{\"u}hwirth, Matthias and Moser, Maximilian and Rosenblum, Michael and Pikovskij, Arkadij}, title = {Disentangling respiratory sinus arrhythmia in heart rate variability records}, series = {Physiological Measurement}, volume = {39}, journal = {Physiological Measurement}, number = {5}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0967-3334}, doi = {10.1088/1361-6579/aabea4}, pages = {12}, year = {2018}, abstract = {Objective: Several different measures of heart rate variability, and particularly of respiratory sinus arrhythmia, are widely used in research and clinical applications. For many purposes it is important to know which features of heart rate variability are directly related to respiration and which are caused by other aspects of cardiac dynamics. Approach: Inspired by ideas from the theory of coupled oscillators, we use simultaneous measurements of respiratory and cardiac activity to perform a nonlinear disentanglement of the heart rate variability into the respiratory-related component and the rest. Main results: The theoretical consideration is illustrated by the analysis of 25 data sets from healthy subjects. In all cases we show how the disentanglement is manifested in the different measures of heart rate variability. Significance: The suggested technique can be exploited as a universal preprocessing tool, both for the analysis of respiratory influence on the heart rate and in cases when effects of other factors on the heart rate variability are in focus.}, language = {en} } @article{NiebuurPuchmayrHeroldetal.2018, author = {Niebuur, Bart-Jan and Puchmayr, Jonas and Herold, Christian and Kreuzer, Lucas P. and Hildebrand, Viet and M{\"u}ller-Buschbaum, Peter and Laschewsky, Andre and Papadakis, Christine M.}, title = {Polysulfobetaines in aqueous solution and in thin film geometry}, series = {Materials}, volume = {11}, journal = {Materials}, number = {5}, publisher = {MDPI}, address = {Basel}, issn = {1996-1944}, doi = {10.3390/ma11050850}, pages = {11}, year = {2018}, abstract = {Polysulfobetaines in aqueous solution show upper critical solution temperature (UCST) behavior. We investigate here the representative of this class of materials, poly (N,N-dimethyl-N-(3-methacrylamidopropyl) ammonio propane sulfonate) (PSPP), with respect to: (i) the dynamics in aqueous solution above the cloud point as function of NaBr concentration; and (ii) the swelling behavior of thin films in water vapor as function of the initial film thickness. For PSPP solutions with a concentration of 5 wt.\%, the temperature dependence of the intensity autocorrelation functions is measured with dynamic light scattering as function of molar mass and NaBr concentration (0-8 mM). We found a scaling of behavior for the scattered intensity and dynamic correlation length. The resulting spinodal temperatures showed a maximum at a certain (small) NaBr concentration, which is similar to the behavior of the cloud points measured previously by turbidimetry. The critical exponent of susceptibility depends on NaBr concentration, with a minimum value where the spinodal temperature is maximum and a trend towards the mean-field value of unity with increasing NaBr concentration. In contrast, the critical exponent of the correlation length does not depend on NaBr concentration and is lower than the value of 0.5 predicted by mean-field theory. For PSPP thin films, the swelling behavior was found to depend on film thickness. A film thickness of about 100 nm turns out to be the optimum thickness needed to obtain fast hydration with H2O.}, language = {en} } @article{IjiriInagakiKuboetal.2018, author = {Ijiri, Akira and Inagaki, Fumio and Kubo, Yusuke and Adhikari, Rishi Ram and Hattori, Shohei and Hoshino, Tatsuhiko and Imachi, Hiroyuki and Kawagucci, Shinsuke and Morono, Yuki and Ohtomo, Yoko and Ono, Shuhei and Sakai, Sanae and Takai, Ken and Toki, Tomohiro and Wang, David T. and Yoshinaga, Marcos Y. and Arnold, Gail L. and Ashi, Juichiro and Case, David H. and Feseker, Tomas and Hinrichs, Kai-Uwe and Ikegawa, Yojiro and Ikehara, Minoru and Kallmeyer, Jens and Kumagai, Hidenori and Lever, Mark Alexander and Morita, Sumito and Nakamura, Ko-ichi and Nakamura, Yuki and Nishizawa, Manabu and Orphan, Victoria J. and Roy, Hans and Schmidt, Frauke and Tani, Atsushi and Tanikawa, Wataru and Terada, Takeshi and Tomaru, Hitoshi and Tsuji, Takeshi and Tsunogai, Urumu and Yamaguchi, Yasuhiko T. and Yoshida, Naohiro}, title = {Deep-biosphere methane production stimulated by geofluids in the Nankai accretionary complex}, series = {Science Advances}, volume = {4}, journal = {Science Advances}, number = {6}, publisher = {American Assoc. for the Advancement of Science}, address = {Washington}, issn = {2375-2548}, doi = {10.1126/sciadv.aao4631}, pages = {15}, year = {2018}, language = {en} } @article{FabianZlatanovicMutzetal.2018, author = {Fabian, Jenny and Zlatanovic, Sanja and Mutz, Michael and Grossart, Hans-Peter and van Geldern, Robert and Ulrich, Andreas and Gleixner, Gerd and Premke, Katrin}, title = {Environmental control on microbial turnover of leaf carbon in streams}, series = {Frontiers in microbiology}, volume = {9}, journal = {Frontiers in microbiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-302X}, doi = {10.3389/fmicb.2018.01044}, pages = {16}, year = {2018}, abstract = {In aquatic ecosystems, light availability can significantly influence microbial turnover of terrestrial organic matter through associated metabolic interactions between phototrophic and heterotrophic communities. However, particularly in streams, microbial functions vary significantly with the structure of the streambed, that is the distribution and spatial arrangement of sediment grains in the streambed. It is therefore essential to elucidate how environmental factors synergistically define the microbial turnover of terrestrial organic matter in order to better understand the ecological role of photoheterotrophic interactions in stream ecosystem processes. In outdoor experimental streams, we examined how the structure of streambeds modifies the influence of light availability on microbial turnover of leaf carbon (C). Furthermore, we investigated whether the studied relationships of microbial leaf C turnover to environmental conditions are affected by flow intermittency commonly occurring in streams. We applied leaves enriched with a C-13-stable isotope tracer and combined quantitative and isotope analyses. We thereby elucidated whether treatment induced changes in C turnover were associated with altered use of leaf C within the microbial food web. Moreover, isotope analyses were combined with measurements of microbial community composition to determine whether changes in community function were associated with a change in community composition. In this study, we present evidence, that environmental factors interactively determine how phototrophs and heterotrophs contribute to leaf C turnover. Light availability promoted the utilization of leaf C within the microbial food web, which was likely associated with a promoted availability of highly bioavailable metabolites of phototrophic origin. However, our results additionally confirm that the structure of the streambed modifies light-related changes in microbial C turnover. From our observations, we conclude that the streambed structure influences the strength of photo-heterotrophic interactions by defining the spatial availability of algal metabolites in the streambed and the composition of microbial communities. Collectively, our multifactorial approach provides valuable insights into environmental controls on the functioning of stream ecosystems.}, language = {en} } @article{StoesselStellmannWillingetal.2018, author = {Stoessel, Daniel and Stellmann, Jan-Patrick and Willing, Anne and Behrens, Birte and Rosenkranz, Sina C. and Hodecker, Sibylle C. and Stuerner, Klarissa H. and Reinhardt, Stefanie and Fleischer, Sabine and Deuschle, Christian and Maetzler, Walter and Berg, Daniela and Heesen, Christoph and Walther, Dirk and Schauer, Nicolas and Friese, Manuel A. and Pless, Ole}, title = {Metabolomic Profiles for Primary Progressive Multiple Sclerosis Stratification and Disease Course Monitoring}, series = {Frontiers in human neuroscienc}, volume = {12}, journal = {Frontiers in human neuroscienc}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1662-5161}, doi = {10.3389/fnhum.2018.00226}, pages = {13}, year = {2018}, abstract = {Primary progressive multiple sclerosis (PPMS) shows a highly variable disease progression with poor prognosis and a characteristic accumulation of disabilities in patients. These hallmarks of PPMS make it difficult to diagnose and currently impossible to efficiently treat. This study aimed to identify plasma metabolite profiles that allow diagnosis of PPMS and its differentiation from the relapsing remitting subtype (RRMS), primary neurodegenerative disease (Parkinson's disease, PD), and healthy controls (HCs) and that significantly change during the disease course and could serve as surrogate markers of multiple sclerosis (MS)-associated neurodegeneration over time. We applied untargeted high-resolution metabolomics to plasma samples to identify PPMS-specific signatures, validated our findings in independent sex- and age-matched PPMS and HC cohorts and built discriminatory models by partial least square discriminant analysis (PLS-DA). This signature was compared to sex- and age-matched RRMS patients, to patients with PD and HC. Finally, we investigated these metabolites in a longitudinal cohort of PPMS patients over a 24-month period. PLS-DA yielded predictive models for classification along with a set of 20 PPMS-specific informative metabolite markers. These metabolites suggest disease-specific alterations in glycerophospholipid and linoleic acid pathways. Notably, the glycerophospholipid LysoPC(20:0) significantly decreased during the observation period. These findings show potential for diagnosis and disease course monitoring, and might serve as biomarkers to assess treatment efficacy in future clinical trials for neuroprotective MS therapies.}, language = {en} } @article{MerksSwinarskiMeyeretal.2018, author = {Merks, Anne Margarete and Swinarski, Marie and Meyer, Alexander Matthias and M{\"u}ller, Nicola Victoria and {\"O}zcan, Ismail and Donat, Stefan and Burger, Alexa and Gilbert, Stephen and Mosimann, Christian and Abdelilah-Seyfried, Salim and Panakova, Daniela}, title = {Planar cell polarity signalling coordinates heart tube remodelling through tissue-scale polarisation of actomyosin activity}, series = {Nature Communications}, volume = {9}, journal = {Nature Communications}, publisher = {Nature Publ. Group}, address = {London}, issn = {2041-1723}, doi = {10.1038/s41467-018-04566-1}, pages = {15}, year = {2018}, abstract = {Development of a multiple-chambered heart from the linear heart tube is inherently linked to cardiac looping. Although many molecular factors regulating the process of cardiac chamber ballooning have been identified, the cellular mechanisms underlying the chamber formation remain unclear. Here, we demonstrate that cardiac chambers remodel by cell neighbour exchange of cardiomyocytes guided by the planar cell polarity (PCP) pathway triggered by two non-canonical Wnt ligands, Wnt5b and Wnt11. We find that PCP signalling coordinates the localisation of actomyosin activity, and thus the efficiency of cell neighbour exchange. On a tissue-scale, PCP signalling planar-polarises tissue tension by restricting the actomyosin contractility to the apical membranes of outflow tract cells. The tissue-scale polarisation of actomyosin contractility is required for cardiac looping that occurs concurrently with chamber ballooning. Taken together, our data reveal that instructive PCP signals couple cardiac chamber expansion with cardiac looping through the organ-scale polarisation of actomyosin-based tissue tension.}, language = {en} } @article{SchleglDittmerHoffmannetal.2018, author = {Schlegl, Sandra and Dittmer, Nina and Hoffmann, Svenja and Voderholzer, Ulrich}, title = {Self-reported quantity, compulsiveness and motives of exercise in patients with eating disorders and healthy controls}, series = {Journal of eating disorders}, volume = {6}, journal = {Journal of eating disorders}, publisher = {BMC}, address = {London}, issn = {2050-2974}, doi = {10.1186/s40337-018-0202-6}, pages = {10}, year = {2018}, abstract = {Background: Compulsive exercise (CE) is a frequent symptom in patients with eating disorders (EDs). It includes, in addition to quantitatively excessive exercise behaviour, a driven aspect and specific motives of exercise. CE is generally associated with worse therapy outcomes. The aims of the study were to compare self-reported quantity of exercise, compulsiveness of exercise as well as motives for exercise between patients with anorexia nervosa (AN), bulimia nervosa (BN) and healthy controls (HC). Additionally, we wanted to explore predictors of compulsive exercise (CE) in each group. Methods: We investigated 335 female participants (n = 226 inpatients, n = 109 HC) and assessed self-reported quantity of exercise, compulsiveness of exercise (Compulsive Exercise Test), motives for exercise (Exercise Motivations Inventory-2), ED symptoms (Eating Disorder Inventory-2), obsessive-compulsiveness (Obsessive-Compulsive Inventory-Revised), general psychopathology (Brief Symptom Inventory-18) and depression (Beck Depression Inventory-2). Results: Both patients with AN and BN exercised significantly more hours per week and showed significantly higher CE than HC; no differences were found between patients with AN and BN. Patients with EDs and HC also partly varied in motives for exercise. Specific motives were enjoyment, challenge, recognition and weight management in patients with EDs in contrast to ill-health avoidance and affiliation in HC. Patients with AN and BN only differed in regard to exercise for appearance reasons in which patients with BN scored higher. The most relevant predictor of CE across groups was exercise for weight and shape reasons. Conclusions: Exercise behaviours and motives differ between patients with EDs and HC. CE was pronounced in both patients with AN and BN. Therefore, future research should focus not only on CE in patients with AN, but also on CE in patients with BN. Similarities in CE in patients with AN and BN support a transdiagnostic approach during the development of interventions specifically targeting CE in patients with EDs.}, language = {en} } @article{StettnerLantuitHeimetal.2018, author = {Stettner, Samuel and Lantuit, Hugues and Heim, Birgit and Eppler, Jayson and Roth, Achim and Bartsch, Annett and Rabus, Bernhard}, title = {TerraSAR-X time series fill a gap in spaceborne snowmelt monitoring of small arctic catchments}, series = {Remote sensing}, volume = {10}, journal = {Remote sensing}, number = {7}, publisher = {MDPI}, address = {Basel}, issn = {2072-4292}, doi = {10.3390/rs10071155}, pages = {26}, year = {2018}, abstract = {The timing of snowmelt is an important turning point in the seasonal cycle of small Arctic catchments. The TerraSAR-X (TSX) satellite mission is a synthetic aperture radar system (SAR) with high potential to measure the high spatiotemporal variability of snow cover extent (SCE) and fractional snow cover (FSC) on the small catchment scale. We investigate the performance of multi-polarized and multi-pass TSX X-Band SAR data in monitoring SCE and FSC in small Arctic tundra catchments of Qikiqtaruk (Herschel Island) off the Yukon Coast in the Western Canadian Arctic. We applied a threshold based segmentation on ratio images between TSX images with wet snow and a dry snow reference, and tested the performance of two different thresholds. We quantitatively compared TSX- and Landsat 8-derived SCE maps using confusion matrices and analyzed the spatiotemporal dynamics of snowmelt from 2015 to 2017 using TSX, Landsat 8 and in situ time lapse data. Our data showed that the quality of SCE maps from TSX X-Band data is strongly influenced by polarization and to a lesser degree by incidence angle. VH polarized TSX data performed best in deriving SCE when compared to Landsat 8. TSX derived SCE maps from VH polarization detected late lying snow patches that were not detected by Landsat 8. Results of a local assessment of TSX FSC against the in situ data showed that TSX FSC accurately captured the temporal dynamics of different snow melt regimes that were related to topographic characteristics of the studied catchments. Both in situ and TSX FSC showed a longer snowmelt period in a catchment with higher contributions of steep valleys and a shorter snowmelt period in a catchment with higher contributions of upland terrain. Landsat 8 had fundamental data gaps during the snowmelt period in all 3 years due to cloud cover. The results also revealed that by choosing a positive threshold of 1 dB, detection of ice layers due to diurnal temperature variations resulted in a more accurate estimation of snow cover than a negative threshold that detects wet snow alone. We find that TSX X-Band data in VH polarization performs at a comparable quality to Landsat 8 in deriving SCE maps when a positive threshold is used. We conclude that TSX data polarization can be used to accurately monitor snowmelt events at high temporal and spatial resolution, overcoming limitations of Landsat 8, which due to cloud related data gaps generally only indicated the onset and end of snowmelt.}, language = {en} } @article{ChenGuentherGrosseetal.2018, author = {Chen, Jie and G{\"u}nther, Frank and Grosse, Guido and Liu, Lin and Lin, Hui}, title = {Sentinel-1 InSAR Measurements of Elevation Changes over Yedoma Uplands on Sobo-Sise Island, Lena Delta}, series = {Remote sensing}, volume = {10}, journal = {Remote sensing}, number = {7}, publisher = {MDPI}, address = {Basel}, issn = {2072-4292}, doi = {10.3390/rs10071152}, pages = {16}, year = {2018}, abstract = {Yedoma-extremely ice-rich permafrost with massive ice wedges formed during the Late Pleistocene-is vulnerable to thawing and degradation under climate warming. Thawing of ice-rich Yedoma results in lowering of surface elevations. Quantitative knowledge about surface elevation changes helps us to understand the freeze-thaw processes of the active layer and the potential degradation of Yedoma deposits. In this study, we use C-band Sentinel-1 InSAR measurements to map the elevation changes over ice-rich Yedoma uplands on Sobo-Sise Island, Lena Delta with frequent revisit observations (as short as six or 12 days). We observe significant seasonal thaw subsidence during summer months and heterogeneous inter-annual elevation changes from 2016-17. We also observe interesting patterns of stronger seasonal thaw subsidence on elevated flat Yedoma uplands by comparing to the surrounding Yedoma slopes. Inter-annual analyses from 2016-17 suggest that our observed positive surface elevation changes are likely caused by the delayed progression of the thaw season in 2017, associated with mean annual air temperature fluctuations.}, language = {en} } @article{JoussetReinschRybergetal.2018, author = {Jousset, Philippe and Reinsch, Thomas and Ryberg, Trond and Blanck, Hanna and Clarke, Andy and Aghayev, Rufat and Hersir, Gylfi P. and Henninges, Jan and Weber, Michael and Krawczyk, Charlotte M.}, title = {Dynamic strain determination using fibre-optic cables allows imaging of seismological and structural features}, series = {Nature Communications}, volume = {9}, journal = {Nature Communications}, publisher = {Nature Publ. Group}, address = {London}, issn = {2041-1723}, doi = {10.1038/s41467-018-04860-y}, pages = {11}, year = {2018}, abstract = {Natural hazard prediction and efficient crust exploration require dense seismic observations both in time and space. Seismological techniques provide ground-motion data, whose accuracy depends on sensor characteristics and spatial distribution. Here we demonstrate that dynamic strain determination is possible with conventional fibre-optic cables deployed for telecommunication. Extending recently distributed acoustic sensing (DAS) studies, we present high resolution spatially un-aliased broadband strain data. We recorded seismic signals from natural and man-made sources with 4-m spacing along a 15-km-long fibre-optic cable layout on Reykjanes Peninsula, SW-Iceland. We identify with unprecedented resolution structural features such as normal faults and volcanic dykes in the Reykjanes Oblique Rift, allowing us to infer new dynamic fault processes. Conventional seismometer recordings, acquired simultaneously, validate the spectral amplitude DAS response between 0.1 and 100 Hz bandwidth. We suggest that the networks of fibre-optic telecommunication lines worldwide could be used as seismometers opening a new window for Earth hazard assessment and exploration.}, language = {en} } @article{SchirrmeisterBobrovRaschkeetal.2018, author = {Schirrmeister, Lutz and Bobrov, Anatoly and Raschke, Elena and Herzschuh, Ulrike and Strauss, Jens and Pestryakova, Luidmila Agafyevna and Wetterich, Sebastian}, title = {Late Holocene ice-wedge polygon dynamics in northeastern Siberian coastal lowlands}, series = {Arctic, antarctic, and alpine research : an interdisciplinary journal}, volume = {50}, journal = {Arctic, antarctic, and alpine research : an interdisciplinary journal}, number = {1}, publisher = {Institute of Arctic and Alpine Research, University of Colorado}, address = {Boulder}, issn = {1523-0430}, doi = {10.1080/15230430.2018.1462595}, pages = {18}, year = {2018}, abstract = {Ice-wedge polygons are common features of northeastern Siberian lowland periglacial tundra landscapes. To deduce the formation and alternation of ice-wedge polygons in the Kolyma Delta and in the Indigirka Lowland, we studied shallow cores, up to 1.3 m deep, from polygon center and rim locations. The formation of well-developed low-center polygons with elevated rims and wet centers is shown by the beginning of peat accumulation, increased organic matter contents, and changes in vegetation cover from Poaceae-, Alnus-, and Betula-dominated pollen spectra to dominating Cyperaceae and Botryoccocus presence, and Carex and Drepanocladus revolvens macro-fossils. Tecamoebae data support such a change from wetland to open-water conditions in polygon centers by changes from dominating eurybiontic and sphagnobiontic to hydrobiontic species assemblages. The peat accumulation indicates low-center polygon formation and started between 2380 +/- 30 and 1676 +/- 32 years before present (BP) in the Kolyma Delta. We recorded an opposite change from open-water to wetland conditions because of rim degradation and consecutive high-center polygon formation in the Indigirka Lowland between 2144 +/- 33 and 1632 +/- 32 years BP. The late Holocene records of polygon landscape development reveal changes in local hydrology and soil moisture.}, language = {en} } @article{SchnitzlerPinzoneAutenriethetal.2018, author = {Schnitzler, Joseph G. and Pinzone, Marianna and Autenrieth, Marijke and van Neer, Abbo and IJsseldijk, Lonneke L. and Barber, Jonathan L. and Deaville, Rob and Jepson, Paul and Brownlow, Andrew and Schaffeld, Tobias and Thome, Jean-Pierre and Tiedemann, Ralph and Das, Krishna and Siebert, Ursula}, title = {Inter-individual differences in contamination profiles as tracer of social group association in stranded sperm whales}, series = {Scientific reports}, volume = {8}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-018-29186-z}, pages = {11}, year = {2018}, abstract = {Ecological and physiological factors lead to different contamination patterns in individual marine mammals. The objective of the present study was to assess whether variations in contamination profiles are indicative of social structures of young male sperm whales as they might reflect a variation in feeding preferences and/or in utilized feeding grounds. We used a total of 61 variables associated with organic compounds and trace element concentrations measured in muscle, liver, kidney and blubber gained from 24 sperm whales that stranded in the North Sea in January and February 2016. Combining contaminant and genetic data, there is evidence for at least two cohorts with different origin among these stranded sperm whales; one from the Canary Island region and one from the northern part of the Atlantic. While genetic data unravel relatedness and kinship, contamination data integrate over areas, where animals occured during their lifetime. Especially in long-lived animals with a large migratory potential, as sperm whales, contamination data may carry highly relevant information about aggregation through time and space.}, language = {en} } @article{ClahsenPaulmannBuddetal.2018, author = {Clahsen, Harald and Paulmann, Silke and Budd, Mary-Jane and Barry, Christopher}, title = {Morphological encoding beyond slots and fillers}, series = {PLoS one}, volume = {13}, journal = {PLoS one}, number = {7}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0199897}, pages = {16}, year = {2018}, abstract = {One important organizational property of morphology is competition. Different means of expression are in conflict with each other for encoding the same grammatical function. In the current study, we examined the nature of this control mechanism by testing the formation of comparative adjectives in English during language production. Event-related brain potentials (ERPs) were recorded during cued silent production, the first study of this kind for comparative adjective formation. We specifically examined the ERP correlates of producing synthetic relative to analytic comparatives, e.g. angriervs. more angry. A frontal, bilaterally distributed, enhanced negative-going waveform for analytic comparatives (vis-a-vis synthetic ones) emerged approximately 300ms after the (silent) production cue. We argue that this ERP effect reflects a control mechanism that constrains grammatically-based computational processes (viz. more comparative formation). We also address the possibility that this particular ERP effect may belong to a family of previously observed negativities reflecting cognitive control monitoring, rather than morphological encoding processes per se.}, language = {en} } @article{GeorgievGrafmuellerBlegeretal.2018, author = {Georgiev, Vasil N. and Grafm{\"u}ller, Andrea and Bl{\´e}ger, David and Hecht, Stefan and Kunstmann, Sonja and Barbirz, Stefanie and Lipowsky, Reinhard and Dimova, Rumiana}, title = {Area increase and budding in giant vesicles triggered by light}, series = {Advanced science}, volume = {5}, journal = {Advanced science}, number = {8}, publisher = {Wiley}, address = {Hoboken}, issn = {2198-3844}, doi = {10.1002/advs.201800432}, pages = {9}, year = {2018}, abstract = {Biomembranes are constantly remodeled and in cells, these processes are controlled and modulated by an assortment of membrane proteins. Here, it is shown that such remodeling can also be induced by photoresponsive molecules. The morphological control of giant vesicles in the presence of a water-soluble ortho-tetrafluoroazobenzene photoswitch (F-azo) is demonstrated and it is shown that the shape transformations are based on an increase in membrane area and generation of spontaneous curvature. The vesicles exhibit budding and the buds can be retracted by using light of a different wavelength. In the presence of F-azo, the membrane area can increase by more than 5\% as assessed from vesicle electrodeformation. To elucidate the underlying molecular mechanism and the partitioning of F-azo in the membrane, molecular dynamics simulations are employed. Comparison with theoretically calculated shapes reveals that the budded shapes are governed by curvature elasticity, that the spontaneous curvature can be decomposed into a local and a nonlocal contribution, and that the local spontaneous curvature is about 1/(2.5 mu m). The results show that exo- and endocytotic events can be controlled by light and that these photoinduced processes provide an attractive method to change membrane area and morphology.}, language = {en} } @article{SultanaSiegKellermannetal.2018, author = {Sultana, Zakia and Sieg, Tobias and Kellermann, Patric and M{\"u}ller, Meike and Kreibich, Heidi}, title = {Assessment of business interruption of flood-affected companies using random forests}, series = {Water}, volume = {10}, journal = {Water}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {2073-4441}, doi = {10.3390/w10081049}, pages = {16}, year = {2018}, abstract = {Losses due to floods have dramatically increased over the past decades, and losses of companies, comprising direct and indirect losses, have a large share of the total economic losses. Thus, there is an urgent need to gain more quantitative knowledge about flood losses, particularly losses caused by business interruption, in order to mitigate the economic loss of companies. However, business interruption caused by floods is rarely assessed because of a lack of sufficiently detailed data. A survey was undertaken to explore processes influencing business interruption, which collected information on 557 companies affected by the severe flood in June 2013 in Germany. Based on this data set, the study aims to assess the business interruption of directly affected companies by means of a Random Forests model. Variables that influence the duration and costs of business interruption were identified by the variable importance measures of Random Forests. Additionally, Random Forest-based models were developed and tested for their capacity to estimate business interruption duration and associated costs. The water level was found to be the most important variable influencing the duration of business interruption. Other important variables, relating to the estimation of business interruption duration, are the warning time, perceived danger of flood recurrence and inundation duration. In contrast, the amount of business interruption costs is strongly influenced by the size of the company, as assessed by the number of employees, emergency measures undertaken by the company and the fraction of customers within a 50 km radius. These results provide useful information and methods for companies to mitigate their losses from business interruption. However, the heterogeneity of companies is relatively high, and sector-specific analyses were not possible due to the small sample size. Therefore, further sector-specific analyses on the basis of more flood loss data of companies are recommended.}, language = {en} } @misc{SchwarzeRiemerMuelleretal.2019, author = {Schwarze, Thomas and Riemer, Janine and M{\"u}ller, Holger and John, Leonard and Holdt, Hans-J{\"u}rgen and Wessig, Pablo}, title = {Na+ Selective Fluorescent Tools Based on Fluorescence Intensity Enhancements, Lifetime Changes, and on a Ratiometric Response}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1136}, issn = {1866-8372}, doi = {10.25932/publishup-43748}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-437482}, pages = {13}, year = {2019}, abstract = {Over the years, we developed highly selective fluorescent probes for K+ in water, which show K+-induced fluorescence intensity enhancements, lifetime changes, or a ratiometric behavior at two emission wavelengths (cf. Scheme 1, K1-K4). In this paper, we introduce selective fluorescent probes for Na+ in water, which also show Na+ induced signal changes, which are analyzed by diverse fluorescence techniques. Initially, we synthesized the fluorescent probes 2, 4, 5, 6 and 10 for a fluorescence analysis by intensity enhancements at one wavelength by varying the Na+ responsive ionophore unit and the fluorophore moiety to adjust different K-d values for an intra- or extracellular Na+ analysis. Thus, we found that 2, 4 and 5 are Na+ selective fluorescent tools, which are able to measure physiologically important Na+ levels at wavelengths higher than 500 nm. Secondly, we developed the fluorescent probes 7 and 8 to analyze precise Na+ levels by fluorescence lifetime changes. Herein, only 8 (K-d=106 mm) is a capable fluorescent tool to measure Na+ levels in blood samples by lifetime changes. Finally, the fluorescent probe 9 was designed to show a Na+ induced ratiometric fluorescence behavior at two emission wavelengths. As desired, 9 (K-d=78 mm) showed a ratiometric fluorescence response towards Na+ ions and is a suitable tool to measure physiologically relevant Na+ levels by the intensity change of two emission wavelengths at 404 nm and 492 nm.}, language = {en} } @misc{PaulyHelleMiramontetal.2018, author = {Pauly, Maren and Helle, Gerhard and Miramont, C{\´e}cile and B{\"u}ntgen, Ulf and Treydte, Kerstin and Reinig, Frederick and Guibal, Fr{\´e}d{\´e}ric and Sivan, Olivier and Heinrich, Ingo and Riedel, Frank and Kromer, Bernd and Balanzategui, Daniel and Wacker, Lukas and Sookdeo, Adam Sookdeo and Brauer, Achim}, title = {Subfossil trees suggest enhanced Mediterranean hydroclimate variability at the onset of the Younger Dryas}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1135}, issn = {1866-8372}, doi = {10.25932/publishup-45916}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-459169}, pages = {10}, year = {2018}, abstract = {Nearly 13,000 years ago, the warming trend into the Holocene was sharply interrupted by a reversal to near glacial conditions. Climatic causes and ecological consequences of the Younger Dryas (YD) have been extensively studied, however proxy archives from the Mediterranean basin capturing this period are scarce and do not provide annual resolution. Here, we report a hydroclimatic reconstruction from stable isotopes (delta O-18, delta C-13) in subfossil pines from southern France. Growing before and during the transition period into the YD (12 900-12 600 cal BP), the trees provide an annually resolved, continuous sequence of atmospheric change. Isotopic signature of tree sourcewater (delta O-18(sw)) and estimates of relative air humidity were reconstructed as a proxy for variations in air mass origin and precipitation regime. We find a distinct increase in inter-annual variability of sourcewater isotopes (delta O-18(sw)), with three major downturn phases of increasing magnitude beginning at 12 740 cal BP. The observed variation most likely results from an amplified intensity of North Atlantic (low delta O-18(sw)) versus Mediterranean (high delta O-18(sw)) precipitation. This marked pattern of climate variability is not seen in records from higher latitudes and is likely a consequence of atmospheric circulation oscillations at the margin of the southward moving polar front.}, language = {en} } @misc{ManzoniČapekPoradaetal.2018, author = {Manzoni, Stefano and Čapek, Petr and Porada, Philipp and Thurner, Martin and Winterdahl, Mattias and Beer, Christian and Br{\"u}chert, Volker and Frouz, Jan and Herrmann, Anke M. and Lindahl, Bj{\"o}rn D. and Lyon, Steve W. and Šantrůčkov{\´a}, Hana and Vico, Giulia and Way, Danielle}, title = {Reviews and syntheses}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1134}, issn = {1866-8372}, doi = {10.25932/publishup-44638}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-446386}, pages = {23}, year = {2018}, abstract = {The cycling of carbon (C) between the Earth surface and the atmosphere is controlled by biological and abiotic processes that regulate C storage in biogeochemical compartments and release to the atmosphere. This partitioning is quantified using various forms of C-use efficiency (CUE) - the ratio of C remaining in a system to C entering that system. Biological CUE is the fraction of C taken up allocated to biosynthesis. In soils and sediments, C storage depends also on abiotic processes, so the term C-storage efficiency (CSE) can be used. Here we first review and reconcile CUE and CSE definitions proposed for autotrophic and heterotrophic organisms and communities, food webs, whole ecosystems and watersheds, and soils and sediments using a common mathematical framework. Second, we identify general CUE patterns; for example, the actual CUE increases with improving growth conditions, and apparent CUE decreases with increasing turnover. We then synthesize > 5000CUE estimates showing that CUE decreases with increasing biological and ecological organization - from uni-cellular to multicellular organisms and from individuals to ecosystems. We conclude that CUE is an emergent property of coupled biological-abiotic systems, and it should be regarded as a flexible and scale-dependent index of the capacity of a given system to effectively retain C.}, language = {en} } @misc{OdongoSchlotzBaldermannetal.2018, author = {Odongo, Grace Akinyi and Schlotz, Nina and Baldermann, Susanne and Neugart, Susanne and Huyskens-Keil, Susanne and Ngwene, Benard and Trierweiler, Bernhard and Schreiner, Monika and Lamy, Evelyn}, title = {African nightshade (Solanum scabrum Mill.)}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1133}, issn = {1866-8372}, doi = {10.25932/publishup-45911}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-459114}, pages = {22}, year = {2018}, abstract = {Plant cultivation and processing may impact nutrient and phytochemical content of vegetables. The present study aimed at determining the influence of cultivation and processing on the health promoting capacity of African nightshade (Solanum scabrum Mill.) leaves, an indigenous vegetable, rich in nutrients and phytochemicals. Anti-genotoxicity against the human liver carcinogen aflatoxin B1 (AFB1) as determined by the comet assay and radical oxygen species (ROS) scavenging capacity of ethanolic and aqueous extracts were investigated in human derived liver (HepG2) cells. ROS scavenging activity was assessed using electron paramagnetic spin resonance and quantification of ARE/Nrf2 mediated gene expression. The cultivation was done under different environmental conditions. The processing included fermentation and cooking; postharvest ultraviolet irradiation (UV-C) treatment was also investigated. Overall, S. scabrum extracts showed strong health promoting potential, the highest potential was observed with the fermented extract, which showed a 60\% reduction of AFB1 induced DNA damage and a 38\% reduction in FeSO4 induced oxidative stress. The content of total polyphenols, carotenoids and chlorophylls was indeed affected by cultivation and processing. Based on the present in vitro findings consumption of S. scabrum leaves could be further encouraged, preferentially after cooking or fermentation of the plant.}, language = {en} } @misc{AsgarimehrWickertReich2019, author = {Asgarimehr, Milad and Wickert, Jens and Reich, Sebastian}, title = {Evaluating impact of rain attenuation on space-borne GNSS Reflectometry wind speeds}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1132}, issn = {1866-8372}, doi = {10.25932/publishup-47344}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-473441}, pages = {20}, year = {2019}, abstract = {The novel space-borne Global Navigation Satellite System Reflectometry (GNSS-R) technique has recently shown promise in monitoring the ocean state and surface wind speed with high spatial coverage and unprecedented sampling rate. The L-band signals of GNSS are structurally able to provide a higher quality of observations from areas covered by dense clouds and under intense precipitation, compared to those signals at higher frequencies from conventional ocean scatterometers. As a result, studying the inner core of cyclones and improvement of severe weather forecasting and cyclone tracking have turned into the main objectives of GNSS-R satellite missions such as Cyclone Global Navigation Satellite System (CYGNSS). Nevertheless, the rain attenuation impact on GNSS-R wind speed products is not yet well documented. Evaluating the rain attenuation effects on this technique is significant since a small change in the GNSS-R can potentially cause a considerable bias in the resultant wind products at intense wind speeds. Based on both empirical evidence and theory, wind speed is inversely proportional to derived bistatic radar cross section with a natural logarithmic relation, which introduces high condition numbers (similar to ill-posed conditions) at the inversions to high wind speeds. This paper presents an evaluation of the rain signal attenuation impact on the bistatic radar cross section and the derived wind speed. This study is conducted simulating GNSS-R delay-Doppler maps at different rain rates and reflection geometries, considering that an empirical data analysis at extreme wind intensities and rain rates is impossible due to the insufficient number of observations from these severe conditions. Finally, the study demonstrates that at a wind speed of 30 m/s and incidence angle of 30 degrees, rain at rates of 10, 15, and 20 mm/h might cause overestimation as large as approximate to 0.65 m/s (2\%), 1.00 m/s (3\%), and 1.3 m/s (4\%), respectively, which are still smaller than the CYGNSS required uncertainty threshold. The simulations are conducted in a pessimistic condition (severe continuous rainfall below the freezing height and over the entire glistening zone) and the bias is expected to be smaller in size in real environments.}, language = {en} } @misc{Hildebrandt2014, author = {Hildebrandt, Dieter}, title = {A software reference architecture for service-oriented 3D geovisualization systems}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1131}, issn = {1866-8372}, doi = {10.25932/publishup-47583}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-475831}, pages = {48}, year = {2014}, abstract = {Modern 3D geovisualization systems (3DGeoVSs) are complex and evolving systems that are required to be adaptable and leverage distributed resources, including massive geodata. This article focuses on 3DGeoVSs built based on the principles of service-oriented architectures, standards and image-based representations (SSI) to address practically relevant challenges and potentials. Such systems facilitate resource sharing and agile and efficient system construction and change in an interoperable manner, while exploiting images as efficient, decoupled and interoperable representations. The software architecture of a 3DGeoVS and its underlying visualization model have strong effects on the system's quality attributes and support various system life cycle activities. This article contributes a software reference architecture (SRA) for 3DGeoVSs based on SSI that can be used to design, describe and analyze concrete software architectures with the intended primary benefit of an increase in effectiveness and efficiency in such activities. The SRA integrates existing, proven technology and novel contributions in a unique manner. As the foundation for the SRA, we propose the generalized visualization pipeline model that generalizes and overcomes expressiveness limitations of the prevalent visualization pipeline model. To facilitate exploiting image-based representations (IReps), the SRA integrates approaches for the representation, provisioning and styling of and interaction with IReps. Five applications of the SRA provide proofs of concept for the general applicability and utility of the SRA. A qualitative evaluation indicates the overall suitability of the SRA, its applications and the general approach of building 3DGeoVSs based on SSI.}, language = {en} } @article{ReindlFinchSchaffenrothetal.2018, author = {Reindl, Nicole and Finch, Nicolle L. and Schaffenroth, Veronika and Barstow, Martin A. and Casewell, Sarah L. and Geier, Stephan Alfred and Bertolami Miller, Marcelo Miguel and Taubenberger, Stefan}, title = {Revealing the true nature of Hen 2-428}, series = {Galaxies}, volume = {6}, journal = {Galaxies}, number = {3}, issn = {2075-4434}, doi = {10.3390/galaxies6030088}, pages = {7}, year = {2018}, abstract = {The nucleus of Hen 2-428 is a short orbital period (4.2 h) spectroscopic binary, whose status as potential supernovae type Ia progenitor has raised some controversy in the literature. We present preliminary results of a thorough analysis of this interesting system, which combines quantitative non-local thermodynamic (non-LTE) equilibrium spectral modelling, radial velocity analysis, multi-band light curve fitting, and state-of-the art stellar evolutionary calculations. Importantly, we find that the dynamical system mass that is derived by using all available He II lines does not exceed the Chandrasekhar mass limit. Furthermore, the individual masses of the two central stars are too small to lead to an SN Ia in case of a dynamical explosion during the merger process.}, language = {en} } @misc{ReindlFinchSchaffenrothetal.2018, author = {Reindl, Nicole and Finch, Nicolle L. and Schaffenroth, Veronika and Barstow, Martin A. and Casewell, Sarah L. and Geier, Stephan Alfred and Bertolami Miller, Marcelo Miguel and Taubenberger, Stefan}, title = {Revealing the true nature of Hen2-428}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1129}, issn = {1866-8372}, doi = {10.25932/publishup-45970}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-459703}, pages = {9}, year = {2018}, abstract = {The nucleus of Hen 2-428 is a short orbital period (4.2 h) spectroscopic binary, whose status as potential supernovae type Ia progenitor has raised some controversy in the literature. We present preliminary results of a thorough analysis of this interesting system, which combines quantitative non-local thermodynamic (non-LTE) equilibrium spectral modelling, radial velocity analysis, multi-band light curve fitting, and state-of-the art stellar evolutionary calculations. Importantly, we find that the dynamical system mass that is derived by using all available He II lines does not exceed the Chandrasekhar mass limit. Furthermore, the individual masses of the two central stars are too small to lead to an SN Ia in case of a dynamical explosion during the merger process.}, language = {en} } @misc{HodgkinsRichardsonDommainetal.2018, author = {Hodgkins, Suzanne B. and Richardson, Curtis J. and Dommain, Ren{\´e} and Wang, Hongjun and Glaser, Paul H. and Verbeke, Brittany and Winkler, B. Rose and Cobb, Alexander R. and Rich, Virginia I. and Missilmani, Malak and Flanagan, Neal and Ho, Mengchi and Hoyt, Alison M. and Harvey, Charles F. and Vining, S. Rose and Hough, Moira A. and Moore, Tim R. and Richard, Pierre J. H. and De La Cruz, Florentino B. and Toufaily, Joumana and Hamdan, Rasha and Cooper, William T. and Chanton, Jeffrey P.}, title = {Tropical peatland carbon storage linked to global latitudinal trends in peat recalcitrance}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1125}, issn = {1866-8372}, doi = {10.25932/publishup-45965}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-459658}, pages = {15}, year = {2018}, abstract = {Peatlands represent large terrestrial carbon banks. Given that most peat accumulates in boreal regions, where low temperatures and water saturation preserve organic matter, the existence of peat in (sub)tropical regions remains enigmatic. Here we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Near-surface low-latitude peat has lower carbohydrate and greater aromatic content than near-surface high-latitude peat, creating a reduced oxidation state and resulting recalcitrance. This recalcitrance allows peat to persist in the (sub)tropics despite warm temperatures. Because we observed similar declines in carbohydrate content with depth in high-latitude peat, our data explain recent field-scale deep peat warming experiments in which catotelm (deeper) peat remained stable despite temperature increases up to 9 degrees C. We suggest that high-latitude deep peat reservoirs may be stabilized in the face of climate change by their ultimately lower carbohydrate and higher aromatic composition, similar to tropical peats.}, language = {en} } @misc{CoutoCruzErtanetal.2017, author = {Couto, Rafael C. and Cruz, Vinicius V. and Ertan, Emelie and Eckert, Sebastian Oliver and Fondell, Mattis and Dantz, Marcus and Kennedy, Brian and Schmitt, Thorsten and Pietzsch, Annette and Guimar{\~a}es, Freddy F. and {\AA}gren, Hans and Gel'mukhanov, Faris and Odelius, Michael and Kimberg, Victor and F{\"o}hlisch, Alexander}, title = {Selective gating to vibrational modes through resonant X-ray scattering}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1124}, issn = {1866-8372}, doi = {10.25932/publishup-43692}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436926}, pages = {9}, year = {2017}, abstract = {The dynamics of fragmentation and vibration of molecular systems with a large number of coupled degrees of freedom are key aspects for understanding chemical reactivity and properties. Here we present a resonant inelastic X-ray scattering (RIXS) study to show how it is possible to break down such a complex multidimensional problem into elementary components. Local multimode nuclear wave packets created by X-ray excitation to different core-excited potential energy surfaces (PESs) will act as spatial gates to selectively probe the particular ground-state vibrational modes and, hence, the PES along these modes. We demonstrate this principle by combining ultra-high resolution RIXS measurements for gas-phase water with state-of-the-art simulations.}, language = {en} } @misc{PratHajnýGrunewaldetal.2018, author = {Pr{\´a}t, Tom{\´a}š and Hajny', Jakub and Grunewald, Wim and Vasileva, Mina and Moln{\´a}r, Gergely and Tejos, Ricardo and Schmid, Markus and Sauer, Michael and Friml, Jiř{\´i}}, title = {WRKY23 is a component of the transcriptional network mediating auxin feedback on PIN polarity}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1123}, issn = {1866-8372}, doi = {10.25932/publishup-44633}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-446331}, pages = {20}, year = {2018}, abstract = {Auxin is unique among plant hormones due to its directional transport that is mediated by the polarly distributed PIN auxin transporters at the plasma membrane. The canalization hypothesis proposes that the auxin feedback on its polar flow is a crucial, plant-specific mechanism mediating multiple self-organizing developmental processes. Here, we used the auxin effect on the PIN polar localization in Arabidopsis thaliana roots as a proxy for the auxin feedback on the PIN polarity during canalization. We performed microarray experiments to find regulators of this process that act downstream of auxin. We identified genes that were transcriptionally regulated by auxin in an AXR3/IAA17-and ARF7/ARF19-dependent manner. Besides the known components of the PIN polarity, such as PID and PIP5K kinases, a number of potential new regulators were detected, among which the WRKY23 transcription factor, which was characterized in more detail. Gain-and loss-of-function mutants confirmed a role for WRKY23 in mediating the auxin effect on the PIN polarity. Accordingly, processes requiring auxin-mediated PIN polarity rearrangements, such as vascular tissue development during leaf venation, showed a higher WRKY23 expression and required the WRKY23 activity. Our results provide initial insights into the auxin transcriptional network acting upstream of PIN polarization and, potentially, canalization-mediated plant development.}, language = {en} } @misc{KuekenSommerYanevaRoderetal.2018, author = {K{\"u}ken, Anika and Sommer, Frederik and Yaneva-Roder, Liliya and Mackinder, Luke C.M. and H{\"o}hne, Melanie and Geimer, Stefan and Jonikas, Martin C. and Schroda, Michael and Stitt, Mark and Nikoloski, Zoran and Mettler-Altmann, Tabea}, title = {Effects of microcompartmentation on flux distribution and metabolic pools in Chlamydomonas reinhardtii chloroplasts}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1122}, issn = {1866-8372}, doi = {10.25932/publishup-44635}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-446358}, pages = {25}, year = {2018}, abstract = {Cells and organelles are not homogeneous but include microcompartments that alter the spatiotemporal characteristics of cellular processes. The effects of microcompartmentation on metabolic pathways are however difficult to study experimentally. The pyrenoid is a microcompartment that is essential for a carbon concentrating mechanism (CCM) that improves the photosynthetic performance of eukaryotic algae. Using Chlamydomonas reinhardtii, we obtained experimental data on photosynthesis, metabolites, and proteins in CCM-induced and CCM-suppressed cells. We then employed a computational strategy to estimate how fluxes through the Calvin-Benson cycle are compartmented between the pyrenoid and the stroma. Our model predicts that ribulose-1,5-bisphosphate (RuBP), the substrate of Rubisco, and 3-phosphoglycerate (3PGA), its product, diffuse in and out of the pyrenoid, respectively, with higher fluxes in CCM-induced cells. It also indicates that there is no major diffusional barrier to metabolic flux between the pyrenoid and stroma. Our computational approach represents a stepping stone to understanding microcompartmentalized CCM in other organisms.}, language = {en} } @article{EckertNorellMiedemaetal.2017, author = {Eckert, Sebastian Oliver and Norell, Jesper and Miedema, Piter S. and Beye, Martin and Fondell, Mattis and Quevedo, Wilson and Kennedy, Brian and Hantschmann, Markus and Pietzsch, Annette and van Kuiken, Benjamin and Ross, Matthew and Minitti, Michael P. and Moeller, Stefan P. and Schlotter, William F. and Khalil, Munira and Odelius, Michael and F{\"o}hlisch, Alexander}, title = {Untersuchung unabh{\"a}ngiger N-H- und N-C-Bindungsverformungen auf ultrakurzen Zeitskalen mit resonanter inelastischer R{\"o}ntgenstreuung}, series = {Angewandte Chemie}, volume = {129}, journal = {Angewandte Chemie}, number = {22}, issn = {1521-3757}, doi = {10.1002/ange.201700239}, pages = {6184 -- 6188}, year = {2017}, abstract = {Die Femtosekundendynamik nach resonanten Photoanregungen mit optischen und R{\"o}ntgenpulsen erm{\"o}glicht eine selektive Verformung von chemischen N-H- und N-C-Bindungen in 2-Thiopyridon in w{\"a}ssriger L{\"o}sung. Die Untersuchung der orbitalspezifischen elektronischen Struktur und ihrer Dynamik auf ultrakurzen Zeitskalen mit resonanter inelastischer R{\"o}ntgenstreuung an der N1s-Resonanz am Synchrotron und dem Freie-Elektronen-Laser LCLS in Kombination mit quantenchemischen Multikonfigurationsberechnungen erbringen den direkten Nachweis dieser kontrollierten photoinduzierten Molek{\"u}lverformungen und ihrer ultrakurzen Zeitskala.}, language = {de} } @misc{EckertNorellMiedemaetal.2017, author = {Eckert, Sebastian Oliver and Norell, Jesper and Miedema, Piter S. and Beye, Martin and Fondell, Mattis and Quevedo, Wilson and Kennedy, Brian and Hantschmann, Markus and Pietzsch, Annette and van Kuiken, Benjamin E. and Ross, Matthew and Minitti, Michael P. and Moeller, Stefan P. and Schlotter, William F. and Khalil, Munira and Odelius, Michael and F{\"o}hlisch, Alexander}, title = {Untersuchung unabh{\"a}ngiger N-H- und N-C-Bindungsverformungen auf ultrakurzen Zeitskalen mit resonanter inelastischer R{\"o}ntgenstreuung}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1121}, issn = {1866-8372}, doi = {10.25932/publishup-43668}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436688}, pages = {7}, year = {2017}, abstract = {Die Femtosekundendynamik nach resonanten Photoanregungen mit optischen und R{\"o}ntgenpulsen erm{\"o}glicht eine selektive Verformung von chemischen N-H- und N-C-Bindungen in 2-Thiopyridon in w{\"a}ssriger L{\"o}sung. Die Untersuchung der orbitalspezifischen elektronischen Struktur und ihrer Dynamik auf ultrakurzen Zeitskalen mit resonanter inelastischer R{\"o}ntgenstreuung an der N1s-Resonanz am Synchrotron und dem Freie-Elektronen-Laser LCLS in Kombination mit quantenchemischen Multikonfigurationsberechnungen erbringen den direkten Nachweis dieser kontrollierten photoinduzierten Molek{\"u}lverformungen und ihrer ultrakurzen Zeitskala.}, language = {de} } @misc{EckertNorellMiedemaetal.2017, author = {Eckert, Sebastian Oliver and Norell, Jesper and Miedema, Piter S. and Beye, Martin and Fondell, Mattis and Quevedo, Wilson and Kennedy, Brian and Hantschmann, Markus and Pietzsch, Annette and van Kuiken, Benjamin E. and Ross, Matthew and Minitti, Michael P. and Moeller, Stefan P. and Schlotter, William F. and Khalil, Munira and Odelius, Michael and F{\"o}hlisch, Alexander}, title = {Ultrafast Independent N-H and N-C Bond Deformation Investigated with Resonant Inelastic X-Ray Scattering}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1115}, issn = {1866-8372}, doi = {10.25932/publishup-43687}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436873}, pages = {7}, year = {2017}, abstract = {The femtosecond excited-state dynamics following resonant photoexcitation enable the selective deformation of N-H and N-C chemical bonds in 2-thiopyridone in aqueous solution with optical or X-ray pulses. In combination with multiconfigurational quantum-chemical calculations, the orbital-specific electronic structure and its ultrafast dynamics accessed with resonant inelastic X-ray scattering at the N 1s level using synchrotron radiation and the soft X-ray free-electron laser LCLS provide direct evidence for this controlled photoinduced molecular deformation and its ultrashort time-scale.}, language = {en} } @misc{LichtDupontNivetPullenetal.2016, author = {Licht, Alexis and Dupont-Nivet, Guillaume and Pullen, Alex and Kapp, Paul and Abels, Hemmo A. and Lai, Zulong and Guo, ZhaoJie and Abell, Jordan and Giesler, Dominique}, title = {Resilience of the Asian atmospheric circulation shown by paleogene dust provenance}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1114}, issn = {1866-8372}, doi = {10.25932/publishup-43638}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436381}, pages = {8}, year = {2016}, abstract = {The onset of modern central Asian atmospheric circulation is traditionally linked to the interplay of surface uplift of the Mongolian and Tibetan-Himalayan orogens, retreat of the Paratethys sea from central Asia and Cenozoic global cooling. Although the role of these players has not yet been unravelled, the vast dust deposits of central China support the presence of arid conditions and modern atmospheric pathways for the last 25 million years (Myr). Here, we present provenance data from older (42-33 Myr) dust deposits, at a time when the Tibetan Plateau was less developed, the Paratethys sea still present in central Asia and atmospheric pCO(2) much higher. Our results show that dust sources and near-surface atmospheric circulation have changed little since at least 42 Myr. Our findings indicate that the locus of central Asian high pressures and concurrent aridity is a resilient feature only modulated by mountain building, global cooling and sea retreat.}, language = {en} } @misc{XiongStolleLuehretal.2016, author = {Xiong, Chao and Stolle, Claudia and L{\"u}hr, Hermann and Park, Jaeheung and Fejer, Bela G. and Kervalishvili, Guram N.}, title = {Scale analysis of equatorial plasma irregularities derived from Swarm constellation}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1112}, issn = {1866-8372}, doi = {10.25932/publishup-43184}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-431842}, pages = {14}, year = {2016}, abstract = {In this study, we investigated the scale sizes of equatorial plasma irregularities (EPIs) using measurements from the Swarm satellites during its early mission and final constellation phases. We found that with longitudinal separation between Swarm satellites larger than 0.4°, no significant correlation was found any more. This result suggests that EPI structures include plasma density scale sizes less than 44 km in the zonal direction. During the Swarm earlier mission phase, clearly better EPI correlations are obtained in the northern hemisphere, implying more fragmented irregularities in the southern hemisphere where the ambient magnetic field is low. The previously reported inverted-C shell structure of EPIs is generally confirmed by the Swarm observations in the northern hemisphere, but with various tilt angles. From the Swarm spacecrafts with zonal separations of about 150 km, we conclude that larger zonal scale sizes of irregularities exist during the early evening hours (around 1900 LT).}, language = {en} } @misc{WurzbacherFuchsAttermeyeretal.2017, author = {Wurzbacher, Christian and Fuchs, Andrea and Attermeyer, Katrin and Frindte, Katharina and Grossart, Hans-Peter and Hupfer, Michael and Casper, Peter and Monaghan, Michael T.}, title = {Shifts among Eukaryota, Bacteria, and Archaea define the vertical organization of a lake sediment}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1111}, issn = {1866-8372}, doi = {10.25932/publishup-43196}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-431965}, pages = {18}, year = {2017}, abstract = {Background Lake sediments harbor diverse microbial communities that cycle carbon and nutrients while being constantly colonized and potentially buried by organic matter sinking from the water column. The interaction of activity and burial remained largely unexplored in aquatic sediments. We aimed to relate taxonomic composition to sediment biogeochemical parameters, test whether community turnover with depth resulted from taxonomic replacement or from richness effects, and to provide a basic model for the vertical community structure in sediments. Methods We analyzed four replicate sediment cores taken from 30-m depth in oligo-mesotrophic Lake Stechlin in northern Germany. Each 30-cm core spanned ca. 170 years of sediment accumulation according to 137Cs dating and was sectioned into layers 1-4 cm thick. We examined a full suite of biogeochemical parameters and used DNA metabarcoding to examine community composition of microbial Archaea, Bacteria, and Eukaryota. Results Community β-diversity indicated nearly complete turnover within the uppermost 30 cm. We observed a pronounced shift from Eukaryota- and Bacteria-dominated upper layers (<5 cm) to Bacteria-dominated intermediate layers (5-14 cm) and to deep layers (>14 cm) dominated by enigmatic Archaea that typically occur in deep-sea sediments. Taxonomic replacement was the prevalent mechanism in structuring the community composition and was linked to parameters indicative of microbial activity (e.g., CO2 and CH4 concentration, bacterial protein production). Richness loss played a lesser role but was linked to conservative parameters (e.g., C, N, P) indicative of past conditions. Conclusions By including all three domains, we were able to directly link the exponential decay of eukaryotes with the active sediment microbial community. The dominance of Archaea in deeper layers confirms earlier findings from marine systems and establishes freshwater sediments as a potential low-energy environment, similar to deep sea sediments. We propose a general model of sediment structure and function based on microbial characteristics and burial processes. An upper "replacement horizon" is dominated by rapid taxonomic turnover with depth, high microbial activity, and biotic interactions. A lower "depauperate horizon" is characterized by low taxonomic richness, more stable "low-energy" conditions, and a dominance of enigmatic Archaea.}, language = {en} } @misc{PloehnEdelmannJaptoketal.2018, author = {Pl{\"o}hn, Svenja and Edelmann, B{\"a}rbel and Japtok, Lukasz and He, Xingxuan and Hose, Matthias and Hansen, Wiebke and Schuchman, Edward H. and Eckstein, Anja and Berchner-Pfannschmidt, Utta}, title = {CD40 enhances sphingolipids in orbital fibroblasts}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1099}, issn = {1866-8372}, doi = {10.25932/publishup-46883}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-468837}, pages = {9}, year = {2018}, abstract = {PURPOSE. Graves' orbitopathy (GO) is an autoimmune orbital disorder associated with Graves' disease caused by thyrotropin receptor autoantibodies. Orbital fibroblasts (OFs) and CD40 play a key role in disease pathogenesis. The bioactive lipid sphingosine-1-phosphate (S1P) has been implicated in promoting adipogenesis, fibrosis, and inflammation in OFs. We investigated the role of CD40 signaling in inducing S1P activity in orbital inflammation. METHODS. OFs and T cells were derived from GO patients and healthy control (Ctl) persons. S1P abundance in orbital tissues was evaluated by immunofluorescence. OFs were stimulated with CD40 ligand and S1P levels were determined by ELISA. Further, activities of acid sphingomyelinase (ASM), acid ceramidase, and sphingosine kinase were measured by ultraperformance liquid chromatography. Sphingosine and ceramide contents were analyzed by mass spectrometry. Finally, the role for S1P in T-cell attraction was investigated by T-cell migration assays. RESULTS. GO orbital tissue showed elevated amounts of S1P as compared to control samples. Stimulation of CD40 induced S1P expression in GO-derived OFs, while Ctl-OFs remained unaffected. A significant increase of ASM and sphingosine kinase activities, as well as lipid formation, was observed in GO-derived OFs. Migration assay of T cells in the presence of SphK inhibitor revealed that S1P released by GO-OFs attracted T cells for migration. CONCLUSIONS. The results demonstrated that CD40 ligand stimulates GO fibroblast to produce S1P, which is a driving force for T-cell migration. The results support the use of S1P receptor signaling modulators in GO management.}, language = {en} } @misc{SchieferdeckerWendler2019, author = {Schieferdecker, Anne and Wendler, Petra}, title = {Structural mapping of missense mutations in the Pex1/Pex6 complex}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1072}, issn = {1866-8372}, doi = {10.25932/publishup-47284}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-472843}, pages = {27}, year = {2019}, abstract = {Peroxisome biogenesis disorders (PBDs) are nontreatable hereditary diseases with a broad range of severity. Approximately 65\% of patients are affected by mutations in the peroxins Pex1 and Pex6. The proteins form the heteromeric Pex1/Pex6 complex, which is important for protein import into peroxisomes. To date, no structural data are available for this AAA+ ATPase complex. However, a wealth of information can be transferred from low-resolution structures of the yeast scPex1/scPex6 complex and homologous, well-characterized AAA+ ATPases. We review the abundant records of missense mutations described in PBD patients with the aim to classify and rationalize them by mapping them onto a homology model of the human Pex1/Pex6 complex. Several mutations concern functionally conserved residues that are implied in ATP hydrolysis and substrate processing. Contrary to fold destabilizing mutations, patients suffering from function-impairing mutations may not benefit from stabilizing agents, which have been reported as potential therapeutics for PBD patients.}, language = {en} } @misc{AyzelIzhitskiy2019, author = {Ayzel, Georgy and Izhitskiy, Alexander}, title = {Climate change impact assessment on freshwater inflow into the Small Aral Sea}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1071}, issn = {1866-8372}, doi = {10.25932/publishup-47279}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-472794}, pages = {21}, year = {2019}, abstract = {During the last few decades, the rapid separation of the Small Aral Sea from the isolated basin has changed its hydrological and ecological conditions tremendously. In the present study, we developed and validated the hybrid model for the Syr Darya River basin based on a combination of state-of-the-art hydrological and machine learning models. Climate change impact on freshwater inflow into the Small Aral Sea for the projection period 2007-2099 has been quantified based on the developed hybrid model and bias corrected and downscaled meteorological projections simulated by four General Circulation Models (GCM) for each of three Representative Concentration Pathway scenarios (RCP). The developed hybrid model reliably simulates freshwater inflow for the historical period with a Nash-Sutcliffe efficiency of 0.72 and a Kling-Gupta efficiency of 0.77. Results of the climate change impact assessment showed that the freshwater inflow projections produced by different GCMs are misleading by providing contradictory results for the projection period. However, we identified that the relative runoff changes are expected to be more pronounced in the case of more aggressive RCP scenarios. The simulated projections of freshwater inflow provide a basis for further assessment of climate change impacts on hydrological and ecological conditions of the Small Aral Sea in the 21st Century.}, language = {en} } @article{GrieveHalesParkeretal.2018, author = {Grieve, Stuart W. D. and Hales, Tristram C. and Parker, Robert N. and Mudd, Simon M. and Clubb, Fiona J.}, title = {Controls on Zero-Order Basin Morphology}, series = {Journal of geophysical research : Earth surface}, volume = {123}, journal = {Journal of geophysical research : Earth surface}, number = {12}, publisher = {American Geophysical Union}, address = {Washington}, issn = {2169-9003}, doi = {10.1029/2017JF004453}, pages = {3269 -- 3291}, year = {2018}, abstract = {Zero-order basins are common features of soil-mantled landscapes, defined as unchanneled basins at the head of a drainage network. Their geometry and volume control how quickly sediment may reaccumulate after landslide evacuation and, more broadly, zero order basins govern the movement of water and sediment from hillslopes to the fluvial network. They also deliver water and sediment to the uppermost portions of the fluvial network. Despite this role as the moderator between hillslope and fluvial processes, little analysis on their morphology has been conducted at the landscape scale. We present a method to identify zero-order basins in landscapes and subsequently quantify their geometric properties using elliptical Fourier analysis. We deploy this method across the Coweeta Hydrologic Laboratory, USA. Properties such as length, relief, width, and concavity follow distinct probability distributions, which may serve as a basis for testing predictions of future landscape evolution models. Surprisingly, in a landscape with an orographic precipitation gradient and large hillslope to channel relief, we observe no correlation between elevation or spatial location and basin geometry. However, we find that two physiographic units in Coweeta have distinct zero-order basin morphologies. These are the steep, thin soiled, high-elevation Nantahala Escarpment and the lower-gradient, lower-elevation, thick soiled remainder of the basin. Our results indicate that basin slope and area negatively covary, producing the distinct forms observed between the two physiographic units, which we suggest arise through competition between spatially variable soil creep and stochastic landsliding.}, language = {en} } @misc{MetinDungSchroeteretal.2018, author = {Metin, Ayse Duha and Dung, Nguyen Viet and Schr{\"o}ter, Kai and Guse, Bj{\"o}rn and Apel, Heiko and Kreibich, Heidi and Vorogushyn, Sergiy and Merz, Bruno}, title = {How do changes along the risk chain affect flood risk?}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1067}, issn = {1866-8372}, doi = {10.25932/publishup-46879}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-468790}, pages = {22}, year = {2018}, abstract = {Flood risk is impacted by a range of physical and socio-economic processes. Hence, the quantification of flood risk ideally considers the complete flood risk chain, from atmospheric processes through catchment and river system processes to damage mechanisms in the affected areas. Although it is generally accepted that a multitude of changes along the risk chain can occur and impact flood risk, there is a lack of knowledge of how and to what extent changes in influencing factors propagate through the chain and finally affect flood risk. To fill this gap, we present a comprehensive sensitivity analysis which considers changes in all risk components, i.e. changes in climate, catchment, river system, land use, assets, and vulnerability. The application of this framework to the mesoscale Mulde catchment in Germany shows that flood risk can vary dramatically as a consequence of plausible change scenarios. It further reveals that components that have not received much attention, such as changes in dike systems or in vulnerability, may outweigh changes in often investigated components, such as climate. Although the specific results are conditional on the case study area and the selected assumptions, they emphasize the need for a broader consideration of potential drivers of change in a comprehensive way. Hence, our approach contributes to a better understanding of how the different risk components influence the overall flood risk.}, language = {en} } @misc{WeiskirchenWeiperTolbaetal.2020, author = {Weiskirchen, Sabine and Weiper, Katharina and Tolba, Ren{\´e} H. and Weiskirchen, Ralf}, title = {All you can feed}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1066}, issn = {1866-8372}, doi = {10.25932/publishup-47246}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-472460}, pages = {42}, year = {2020}, abstract = {The laboratory mouse is the most common used mammalian research model in biomedical research. Usually these animals are maintained in germ-free, gnotobiotic, or specific-pathogen-free facilities. In these facilities, skilled staff takes care of the animals and scientists usually don't pay much attention about the formulation and quality of diets the animals receive during normal breeding and keeping. However, mice have specific nutritional requirements that must be met to guarantee their potential to grow, reproduce and to respond to pathogens or diverse environmental stress situations evoked by handling and experimental interventions. Nowadays, mouse diets for research purposes are commercially manufactured in an industrial process, in which the safety of food products is addressed through the analysis and control of all biological and chemical materials used for the different diet formulations. Similar to human food, mouse diets must be prepared under good sanitary conditions and truthfully labeled to provide information of all ingredients. This is mandatory to guarantee reproducibility of animal studies. In this review, we summarize some information on mice research diets and general aspects of mouse nutrition including nutrient requirements of mice, leading manufacturers of diets, origin of nutrient compounds, and processing of feedstuffs for mice including dietary coloring, autoclaving and irradiation. Furthermore, we provide some critical views on the potential pitfalls that might result from faulty comparisons of grain-based diets with purified diets in the research data production resulting from confounding nutritional factors.}, language = {en} } @misc{AlHalbouniHolohanTaherietal.2018, author = {Al-Halbouni, Djamil and Holohan, Eoghan P. and Taheri, Abbas and Sch{\"o}pfer, Martin P. J. and Emam, Sacha and Dahm, Torsten}, title = {Geomechanical modelling of sinkhole development using distinct elements}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1061}, issn = {1866-8372}, doi = {10.25932/publishup-46843}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-468435}, pages = {35}, year = {2018}, abstract = {Mechanical and/or chemical removal of material from the subsurface may generate large subsurface cavities, the destabilisation of which can lead to ground collapse and the formation of sinkholes. Numerical simulation of the interaction of cavity growth, host material deformation and overburden collapse is desirable to better understand the sinkhole hazard but is a challenging task due to the involved high strains and material discontinuities. Here, we present 2-D distinct element method numerical simulations of cavity growth and sinkhole development. Firstly, we simulate cavity formation by quasi-static, stepwise removal of material in a single growing zone of an arbitrary geometry and depth. We benchmark this approach against analytical and boundary element method models of a deep void space in a linear elastic material. Secondly, we explore the effects of properties of different uniform materials on cavity stability and sinkhole development. We perform simulated biaxial tests to calibrate macroscopic geotechnical parameters of three model materials representative of those in which sinkholes develop at the Dead Sea shoreline: mud, alluvium and salt. We show that weak materials do not support large cavities, leading to gradual sagging or suffusion-style subsidence. Strong materials support quasi-stable to stable cavities, the overburdens of which may fail suddenly in a caprock or bedrock collapse style. Thirdly, we examine the consequences of layered arrangements of weak and strong materials. We find that these are more susceptible to sinkhole collapse than uniform materials not only due to a lower integrated strength of the overburden but also due to an inhibition of stabilising stress arching. Finally, we compare our model sinkhole geometries to observations at the Ghor Al-Haditha sinkhole site in Jordan. Sinkhole depth ∕ diameter ratios of 0.15 in mud, 0.37 in alluvium and 0.33 in salt are reproduced successfully in the calibrated model materials. The model results suggest that the observed distribution of sinkhole depth ∕ diameter values in each material type may partly reflect sinkhole growth trends.}, language = {en} } @misc{OmoriWinterShinoharaetal.2018, author = {Omori, Toshihiro and Winter, Katja and Shinohara, Kyosuke and Hamada, Hiroshi and Ishikawa, Takuji}, title = {Simulation of the nodal flow of mutant embryos with a small number of cilia}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, number = {1056}, issn = {1866-8372}, doi = {10.25932/publishup-46873}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-468734}, pages = {17}, year = {2018}, abstract = {Left-right (L-R) asymmetry in the body plan is determined by nodal flow in vertebrate embryos. Shinohara et al. (Shinohara K et al. 2012 Nat. Commun. 3, 622 (doi:10.1038/ncomms1624)) used Dpcd and Rfx3 mutant mouse embryos and showed that only a few cilia were sufficient to achieve L-R asymmetry. However, the mechanism underlying the breaking of symmetry by such weak ciliary flow is unclear. Flow-mediated signals associated with the L-R asymmetric organogenesis have not been clarified, and two different hypotheses-vesicle transport and mechanosensing-are now debated in the research field of developmental biology. In this study, we developed a computational model of the node system reported by Shinohara et al. and examined the feasibilities of the two hypotheses with a small number of cilia. With the small number of rotating cilia, flow was induced locally and global strong flow was not observed in the node. Particles were then effectively transported only when they were close to the cilia, and particle transport was strongly dependent on the ciliary positions. Although the maximum wall shear rate was also influenced by ciliary position, the mean wall shear rate at the perinodal wall increased monotonically with the number of cilia. We also investigated the membrane tension of immotile cilia, which is relevant to the regulation of mechanotransduction. The results indicated that tension of about 0.1 mu Nm(-1) was exerted at the base even when the fluid shear rate was applied at about 0.1 s(-1). The area of high tension was also localized at the upstream side, and negative tension appeared at the downstream side. Such localization may be useful to sense the flow direction at the periphery, as time-averaged anticlockwise circulation was induced in the node by rotation of a few cilia. Our numerical results support the mechanosensing hypothesis, and we expect that our study will stimulate further experimental investigations of mechanotransduction in the near future.}, language = {en} } @misc{KashkarovObrosovSutyginaetal.2018, author = {Kashkarov, Egor B. and Obrosov, Aleksei and Sutygina, Alina N. and Uludintceva, Elena and Mitrofanov, Andrei and Weiß, Sabine}, title = {Hydrogen permeation, and mechanical and tribological behavior, of CrNx coatings deposited at various bias voltages on IN718 by direct current reactive sputtering}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, number = {1017}, issn = {1866-8372}, doi = {10.25932/publishup-45984}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-459846}, pages = {14}, year = {2018}, abstract = {In the current work, the microstructure, hydrogen permeability, and properties of chromium nitride (CrNx) thin films deposited on the Inconel 718 superalloy using direct current reactive sputtering are investigated. The influence of the substrate bias voltage on the crystal structure, mechanical, and tribological properties before and after hydrogen exposure was studied. It was found that increasing the substrate bias voltage leads to densification of the coating. X-ray diffraction (XRD) results reveal a change from mixed fcc-CrN + hcp-Cr2N to the approximately stoichiometric hcp-Cr2N phase with increasing substrate bias confirmed by wavelength-dispersive X-ray spectroscopy (WDS). The texture coefficients of (113), (110), and (111) planes vary significantly with increasing substrate bias voltage. The hydrogen permeability was measured by gas-phase hydrogenation. The CrN coating deposited at 60 V with mixed c-CrN and (113) textured hcp-Cr2N phases exhibits the lowest hydrogen absorption at 873 K. It is suggested that the crystal orientation is only one parameter influencing the permeation resistance of the CrNx coating together with the film structure, the presence of mixing phases, and the packing density of the structure. After hydrogenation, the hardness increased for all coatings, which could be related to the formation of a Cr2O3 oxide film on the surface, as well as the defect formation after hydrogen loading. Tribological tests reveal that hydrogenation leads to a decrease of the friction coefficient by up to 40\%. The lowest value of 0.25 +/- 0.02 was reached for the CrNx coating deposited at 60 V after hydrogenation.}, language = {en} }