@article{FerTietjenJeltschetal.2017, author = {Fer, Istem and Tietjen, Britta and Jeltsch, Florian and Wolff, Christian Michael}, title = {The influence of El Nino-Southern Oscillation regimes on eastern African vegetation and its future implications under the RCP8.5 warming scenario}, series = {Biogeosciences}, volume = {14}, journal = {Biogeosciences}, publisher = {Copernicus}, address = {G{\"o}ttingen}, issn = {1726-4170}, doi = {10.5194/bg-14-4355-2017}, pages = {4355 -- 4374}, year = {2017}, abstract = {The El Nino-Southern Oscillation (ENSO) is the main driver of the interannual variability in eastern African rainfall, with a significant impact on vegetation and agriculture and dire consequences for food and social security. In this study, we identify and quantify the ENSO contribution to the eastern African rainfall variability to forecast future eastern African vegetation response to rainfall variability related to a predicted intensified ENSO. To differentiate the vegetation variability due to ENSO, we removed the ENSO signal from the climate data using empirical orthogonal teleconnection (EOT) analysis. Then, we simulated the ecosystem carbon and water fluxes under the historical climate without components related to ENSO teleconnections. We found ENSO-driven patterns in vegetation response and confirmed that EOT analysis can successfully produce coupled tropical Pacific sea surface temperature-eastern African rainfall teleconnection from observed datasets. We further simulated eastern African vegetation response under future climate change as it is projected by climate models and under future climate change combined with a predicted increased ENSO intensity. Our EOT analysis highlights that climate simulations are still not good at capturing rainfall variability due to ENSO, and as we show here the future vegetation would be different from what is simulated under these climate model outputs lacking accurate ENSO contribution. We simulated considerable differences in eastern African vegetation growth under the influence of an intensified ENSO regime which will bring further environmental stress to a region with a reduced capacity to adapt effects of global climate change and food security.}, language = {en} } @article{BoessenkoolBuergerHeistermann2017, author = {B{\"o}ssenkool, Berry and B{\"u}rger, Gerd and Heistermann, Maik}, title = {Effects of sample size on estimation of rainfall extremes at high temperatures}, series = {Natural hazards and earth system sciences}, volume = {17}, journal = {Natural hazards and earth system sciences}, publisher = {Copernicus}, address = {G{\"o}ttingen}, issn = {1561-8633}, doi = {10.5194/nhess-17-1623-2017}, pages = {1623 -- 1629}, year = {2017}, abstract = {High precipitation quantiles tend to rise with temperature, following the so-called Clausius-Clapeyron (CC) scaling. It is often reported that the CC-scaling relation breaks down and even reverts for very high temperatures. In our study, we investigate this reversal using observational climate data from 142 stations across Germany. One of the suggested meteorological explanations for the breakdown is limited moisture supply. Here we argue that, instead, it could simply originate from undersampling. As rainfall frequency generally decreases with higher temperatures, rainfall intensities as dictated by CC scaling are less likely to be recorded than for moderate temperatures. Empirical quantiles are conventionally estimated from order statistics via various forms of plotting position formulas. They have in common that their largest representable return period is given by the sample size. In small samples, high quantiles are underestimated accordingly. The small-sample effect is weaker, or disappears completely, when using parametric quantile estimates from a generalized Pareto distribution (GPD) fitted with L moments. For those, we obtain quantiles of rainfall intensities that continue to rise with temperature.}, language = {en} } @misc{KnapmeyerEndrunGolombekOhrnberger2017, author = {Knapmeyer-Endrun, Brigitte and Golombek, Matthew P. and Ohrnberger, Matthias}, title = {Rayleigh Wave Ellipticity Modeling and Inversion for Shallow Structure at the Proposed InSight Landing Site in Elysium Planitia, Mars}, series = {Space science reviews}, volume = {211}, journal = {Space science reviews}, publisher = {Springer}, address = {Dordrecht}, issn = {0038-6308}, doi = {10.1007/s11214-016-0300-1}, pages = {339 -- 382}, year = {2017}, abstract = {The SEIS (Seismic Experiment for Interior Structure) instrument onboard the InSight mission will be the first seismometer directly deployed on the surface of Mars. From studies on the Earth and the Moon, it is well known that site amplification in low-velocity sediments on top of more competent rocks has a strong influence on seismic signals, but can also be used to constrain the subsurface structure. Here we simulate ambient vibration wavefields in a model of the shallow sub-surface at the InSight landing site in Elysium Planitia and demonstrate how the high-frequency Rayleigh wave ellipticity can be extracted from these data and inverted for shallow structure. We find that, depending on model parameters, higher mode ellipticity information can be extracted from single-station data, which significantly reduces uncertainties in inversion. Though the data are most sensitive to properties of the upper-most layer and show a strong trade-off between layer depth and velocity, it is possible to estimate the velocity and thickness of the sub-regolith layer by using reasonable constraints on regolith properties. Model parameters are best constrained if either higher mode data can be used or additional constraints on regolith properties from seismic analysis of the hammer strokes of InSight's heat flow probe HP3 are available. In addition, the Rayleigh wave ellipticity can distinguish between models with a constant regolith velocity and models with a velocity increase in the regolith, information which is difficult to obtain otherwise.}, language = {en} } @article{BeniniCapoferriDappiaggi2017, author = {Benini, Marco and Capoferri, Matteo and Dappiaggi, Claudio}, title = {Hadamard States for Quantum Abelian Duality}, series = {Annales de l'Institut Henri Poincar{\´e}}, volume = {18}, journal = {Annales de l'Institut Henri Poincar{\´e}}, publisher = {Springer}, address = {Basel}, issn = {1424-0637}, doi = {10.1007/s00023-017-0593-y}, pages = {3325 -- 3370}, year = {2017}, abstract = {Abelian duality is realized naturally by combining differential cohomology and locally covariant quantum field theory. This leads to a -algebra of observables, which encompasses the simultaneous discretization of both magnetic and electric fluxes. We discuss the assignment of physically well-behaved states on this algebra and the properties of the associated GNS triple. We show that the algebra of observables factorizes as a suitable tensor product of three -algebras: the first factor encodes dynamical information, while the other two capture topological data corresponding to electric and magnetic fluxes. On the former factor and in the case of ultra-static globally hyperbolic spacetimes with compact Cauchy surfaces, we exhibit a state whose two-point correlation function has the same singular structure of a Hadamard state. Specifying suitable counterparts also on the topological factors, we obtain a state for the full theory, ultimately implementing Abelian duality transformations as Hilbert space isomorphisms.}, language = {en} } @article{Goychuk2017, author = {Goychuk, Igor}, title = {Fractional Bhatnagar-Gross-Krook kinetic equation}, series = {The European physical journal : B, Condensed matter and complex systems}, volume = {90}, journal = {The European physical journal : B, Condensed matter and complex systems}, publisher = {Springer}, address = {New York}, issn = {1434-6028}, doi = {10.1140/epjb/e2017-80297-x}, pages = {13}, year = {2017}, abstract = {The linear Boltzmann equation approach is generalized to describe fractional superdiffusive transport of the Levy walk type in external force fields. The time distribution between scattering events is assumed to have a finite mean value and infinite variance. It is completely characterized by the two scattering rates, one fractional and a normal one, which defines also the mean scattering rate. We formulate a general fractional linear Boltzmann equation approach and exemplify it with a particularly simple case of the Bohm and Gross scattering integral leading to a fractional generalization of the Bhatnagar, Gross and Krook kinetic equation. Here, at each scattering event the particle velocity is completely randomized and takes a value from equilibrium Maxwell distribution at a given fixed temperature. We show that the retardation effects are indispensable even in the limit of infinite mean scattering rate and argue that this novel fractional kinetic equation provides a viable alternative to the fractional Kramers-Fokker-Planck (KFP) equation by Barkai and Silbey and its generalization by Friedrich et al. based on the picture of divergent mean time between scattering events. The case of divergent mean time is also discussed at length and compared with the earlier results obtained within the fractional KFP. Also a phenomenological fractional BGK equation without retardation effects is proposed in the limit of infinite scattering rates. It cannot be, however, rigorously derived from a scattering model, being rather clever postulated. It this respect, this retardationless equation is similar to the fractional KFP by Barkai and Silbey. However, it corresponds to the opposite, much more physical limit and, therefore, also presents a viable alternative.}, language = {en} } @article{BaumbachSiegmundMittermeieretal.2017, author = {Baumbach, Lukas and Siegmund, Jonatan F. and Mittermeier, Magdalena and Donner, Reik Volker}, title = {Impacts of temperature extremes on European vegetation during the growing season}, series = {Biogeosciences}, volume = {14}, journal = {Biogeosciences}, publisher = {Copernicus}, address = {G{\"o}ttingen}, issn = {1726-4170}, doi = {10.5194/bg-14-4891-2017}, pages = {4891 -- 4903}, year = {2017}, abstract = {Temperature is a key factor controlling plant growth and vitality in the temperate climates of the mid-latitudes like in vast parts of the European continent. Beyond the effect of average conditions, the timings and magnitudes of temperature extremes play a particularly crucial role, which needs to be better understood in the context of projected future rises in the frequency and/or intensity of such events. In this work, we employ event coincidence analysis (ECA) to quantify the likelihood of simultaneous occurrences of extremes in daytime land surface temperature anomalies (LSTAD) and the normalized difference vegetation index (NDVI). We perform this analysis for entire Europe based upon remote sensing data, differentiating between three periods corresponding to different stages of plant development during the growing season. In addition, we analyze the typical elevation and land cover type of the regions showing significantly large event coincidences rates to identify the most severely affected vegetation types. Our results reveal distinct spatio-temporal impact patterns in terms of extraordinarily large co-occurrence rates between several combinations of temperature and NDVI extremes. Croplands are among the most frequently affected land cover types, while elevation is found to have only a minor effect on the spatial distribution of corresponding extreme weather impacts. These findings provide important insights into the vulnerability of European terrestrial ecosystems to extreme temperature events and demonstrate how event-based statistics like ECA can provide a valuable perspective on environmental nexuses.}, language = {en} } @article{MajdaGronesSintornetal.2017, author = {Majda, Mateusz and Grones, Peter and Sintorn, Ida-Maria and Vain, Thomas and Milani, Pascale and Krupinski, Pawel and Zagorska-Marek, Beata and Viotti, Corrado and Jonsson, Henrik and Mellerowicz, Ewa J. and Hamant, Olivier and Robert, Stephanie}, title = {Mechanochemical Polarization of Contiguous Cell Walls Shapes Plant Pavement Cells}, series = {Developmental cell}, volume = {43}, journal = {Developmental cell}, publisher = {Cell Press}, address = {Cambridge}, issn = {1534-5807}, doi = {10.1016/j.devcel.2017.10.017}, pages = {290 -- +}, year = {2017}, abstract = {The epidermis of aerial plant organs is thought to be limiting for growth, because it acts as a continuous load-bearing layer, resisting tension. Leaf epidermis contains jigsaw puzzle piece-shaped pavement cells whose shape has been proposed to be a result of subcellular variations in expansion rate that induce local buckling events. Paradoxically, such local compressive buckling should not occur given the tensile stresses across the epidermis. Using computational modeling, we show that the simplest scenario to explain pavement cell shapes within an epidermis under tension must involve mechanical wall heterogeneities across and along the anticlinal pavement cell walls between adjacent cells. Combining genetics, atomic force microscopy, and immunolabeling, we demonstrate that contiguous cell walls indeed exhibit hybrid mechanochemical properties. Such biochemical wall heterogeneities precede wall bending. Altogether, this provides a possible mechanism for the generation of complex plant cell shapes.}, language = {en} } @article{KurzeHeinkenFartmann2017, author = {Kurze, Susanne and Heinken, Thilo and Fartmann, Thomas}, title = {Nitrogen enrichment of host plants has mostly beneficial effects on the life-history traits of nettle-feeding butterflies}, series = {Acta oecologica : international journal of ecology}, volume = {85}, journal = {Acta oecologica : international journal of ecology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1146-609X}, doi = {10.1016/j.actao.2017.11.005}, pages = {157 -- 164}, year = {2017}, abstract = {Butterflies rank among the most threatened animal groups throughout Europe. However, current population trends differ among species. The nettle-feeding butterflies Aglais io and Aglais urticae cope successfully with the anthropogenic land-use change. Both species are assumed to be pre-adapted to higher nitrogen contents in their host plant, stinging nettle (Urtica dioica). However, it is currently unknown, whether this pre-adaptation enables both Aglais species to cope successfully or even to benefit from the excessive nitrogen availabilities in nettles growing in modern farmlands. For this reason, this study focused on the response of both Aglais species to unfertilized nettles compared to nettles receiving 150 or 300 kg N ha(-1) yr(-1) (i.e., common fertilizer quantities of modern-day agriculture). Fertilized nettles were characterized by higher nitrogen concentrations and lower C:N ratios compared to the control group. In both Aglais species, the individuals feeding on fertilized nettles had higher survival rates, shorter larval periods and heavier pupae and, in A. urticae also longer forewings. All these trait shifts are beneficial for the individuals, lowering their risk to die before reproduction and increasing their reproductive potential. These responses agree with the well-accepted nitrogen-limitation hypothesis predicting a positive relationship between the nitrogen content of the diet and the performance of herbivorous insects. Furthermore, our findings suggest that the increasing abundance of both Aglais species may result not only from the increasing spread of nettles into the farmland but also from changes in their quality due to the eutrophication of the landscape during recent decades.}, language = {en} } @article{DelleSideNassisiPennettaetal.2017, author = {Delle Side, Domenico and Nassisi, Vincenzo and Pennetta, Cecilia and Alifano, Pietro and Di Salvo, Marco and Tala, Adelfia and Chechkin, Aleksei V. and Seno, Flavio and Trovato, Antonio}, title = {Bacterial bioluminescence onset and quenching: a dynamical model for a quorum sensing-mediated property}, series = {Royal Society Open Science}, volume = {4}, journal = {Royal Society Open Science}, publisher = {Royal Society}, address = {London}, issn = {2054-5703}, doi = {10.1098/rsos.171586}, pages = {12}, year = {2017}, abstract = {We present an effective dynamical model for the onset of bacterial bioluminescence, one of the most studied quorum sensing-mediated traits. Our model is built upon simple equations that describe the growth of the bacterial colony, the production and accumulation of autoinducer signal molecules, their sensing within bacterial cells, and the ensuing quorum activation mechanism that triggers bioluminescent emission. The model is directly tested to quantitatively reproduce the experimental distributions of photon emission times, previously measured for bacterial colonies of Vibrio jasicida, a luminescent bacterium belonging to the Harveyi clade, growing in a highly drying environment. A distinctive and novel feature of the proposed model is bioluminescence 'quenching' after a given time elapsed from activation. Using an advanced fitting procedure based on the simulated annealing algorithm, we are able to infer from the experimental observations the biochemical parameters used in the model. Such parameters are in good agreement with the literature data. As a further result, we find that, at least in our experimental conditions, light emission in bioluminescent bacteria appears to originate from a subtle balance between colony growth and quorum activation due to autoinducers diffusion, with the two phenomena occurring on the same time scale. This finding is consistent with a negative feedback mechanism previously reported for Vibrio harveyi.}, language = {en} } @article{DennisPatelOliveretal.2017, author = {Dennis, Alice B. and Patel, Vilas and Oliver, Kerry M. and Vorburger, Christoph}, title = {Parasitoid gene expression changes after adaptation to symbiont-protected hosts}, series = {Evolution}, volume = {71}, journal = {Evolution}, publisher = {Wiley}, address = {Hoboken}, issn = {0014-3820}, doi = {10.1111/evo.13333}, pages = {2599 -- 2617}, year = {2017}, abstract = {Reciprocal selection between aphids, their protective endosymbionts, and the parasitoid wasps that prey upon them offers an opportunity to study the basis of their coevolution. We investigated adaptation to symbiont\&\#8208;conferred defense by rearing the parasitoid wasp Lysiphlebus fabarum on aphids (Aphis fabae) possessing different defensive symbiont strains (Hamiltonella defensa). After ten generations of experimental evolution, wasps showed increased abilities to parasitize aphids possessing the H. defensa strain they evolved with, but not aphids possessing the other strain. We show that the two symbiont strains encode different toxins, potentially creating different targets for counter\&\#8208;adaptation. Phenotypic and behavioral comparisons suggest that neither life\&\#8208;history traits nor oviposition behavior differed among evolved parasitoid lineages. In contrast, comparative transcriptomics of adult female wasps identified a suite of differentially expressed genes among lineages, even when reared in a common, symbiont\&\#8208;free, aphid host. In concurrence with the specificity of each parasitoid lineages' infectivity, most differentially expressed parasitoid transcripts were also lineage\&\#8208;specific. These transcripts are enriched with putative venom toxins and contain highly expressed, potentially defensive viral particles. Together, these results suggest that wild populations of L. fabarum employ a complicated offensive arsenal with sufficient genetic variation for wasps to adapt rapidly and specifically to their hosts' microbial defenses.}, language = {en} } @article{WittEbertMeyeretal.2017, author = {Witt, Barbara and Ebert, Franziska and Meyer, S{\"o}ren and Francesconi, Kevin A. and Schwerdtle, Tanja}, title = {Assessing neurodevelopmental effects of arsenolipids in pre-differentiated human neurons}, series = {Molecular nutrition \& food research : bioactivity, chemistry, immunology, microbiology, safety, technology}, volume = {61}, journal = {Molecular nutrition \& food research : bioactivity, chemistry, immunology, microbiology, safety, technology}, publisher = {Wiley}, address = {Hoboken}, issn = {1613-4125}, doi = {10.1002/mnfr.201700199}, pages = {10}, year = {2017}, abstract = {Scope: In the general population exposure to arsenic occurs mainly via diet. Highest arsenic concentrations are found in seafood, where arsenic is present predominantly in its organic forms including arsenolipids. Since recent studies have provided evidence that arsenolipids could reach the brain of an organism and exert toxicity in fully differentiated human neurons, this work aims to assess the neurodevelopmental toxicity of arsenolipids. Methods and results: Neurodevelopmental effects of three arsenic-containing hydrocarbons (AsHC), two arsenic-containing fatty acids (AsFA), arsenite and dimethylarsinic acid (DMA(V)) were characterized in pre-differentiated human neurons. AsHCs and arsenite caused substantial cytotoxicity in a similar, low concentration range, whereas AsFAs and DMA(V) were less toxic. AsHCs were highly accessible for cells and exerted pronounced neurodevelopmental effects, with neurite outgrowth and the mitochondrial membrane potential being sensitive endpoints; arsenite did not substantially decrease those two endpoints. In fully differentiated neurons, arsenite and AsHCs caused neurite toxicity. Conclusion: These results indicate for a neurodevelopmental potential of AsHCs. Taken into account the possibility that AsHCs might easily reach the developing brain when exposed during early life, neurotoxicity and neurodevelopmental toxicity cannot be excluded. Further studies are needed in order to progress the urgently needed risk assessment.}, language = {en} } @article{MaoAryalLangeneckeretal.2017, author = {Mao, Hailiang and Aryal, Bibek and Langenecker, Tobias and Hagmann, Jorg and Geisler, Markus and Grebe, Markus}, title = {Arabidopsis BTB/POZ protein-dependent PENETRATION3 trafficking and disease susceptibility}, series = {Nature plants}, volume = {3}, journal = {Nature plants}, publisher = {Nature Publ. Group}, address = {London}, issn = {2055-026X}, doi = {10.1038/s41477-017-0039-z}, pages = {854 -- 858}, year = {2017}, abstract = {The outermost cell layer of plant roots (epidermis) constantly encounters environmental challenges. The epidermal outer plasma membrane domain harbours the PENETRATION3 (PEN3)/ABCG36/PDR8 ATP-binding cassette transporter that confers non-host resistance to several pathogens. Here, we show that the Arabidopsis ENDOPLASMIC RETICULUM-ARRESTED PEN3 (EAP3) BTB/POZ-domain protein specifically mediates PEN3 exit from the endoplasmic reticulum and confers resistance to a root-penetrating fungus, providing prime evidence for BTB/POZ-domain protein-dependent membrane trafficking underlying disease resistance.}, language = {en} } @article{AichnerHiltPerillonetal.2017, author = {Aichner, Bernhard and Hilt, Sabine and Perillon, Cecile and Gillefalk, Mikael and Sachse, Dirk}, title = {Biosynthetic hydrogen isotopic fractionation factors during lipid synthesis in submerged aquatic macrophytes: Effect of groundwater discharge and salinity}, series = {Organic geochemistry : the international journal for rapid publication of current research in organic geochemistry and biochemistry}, volume = {113}, journal = {Organic geochemistry : the international journal for rapid publication of current research in organic geochemistry and biochemistry}, publisher = {Elsevier}, address = {Oxford}, issn = {0146-6380}, doi = {10.1016/j.orggeochem.2017.07.021}, pages = {10 -- 16}, year = {2017}, abstract = {Sedimentary lipid biomarkers have become widely used tools for reconstructing past climatic and ecological changes due to their ubiquitous occurrence in lake sediments. In particular, the hydrogen isotopic composition (expressed as delta D values) of leaf wax lipids derived from terrestrial plants has been a focus of research during the last two decades and the understanding of competing environmental and plant physiological factors influencing the delta D values has greatly improved. Comparatively less attention has been paid to lipid biomarkers derived from aquatic plants, although these compounds are abundant in many lacustrine sediments. We therefore conducted a field and laboratory experiment to study the effect of salinity and groundwater discharge on the isotopic composition of aquatic plant biomarkers. We analyzed samples of the common submerged plant species, Potamogeton pectinatus (sago pondweed), which has a wide geographic distribution and can tolerate high salinity. We tested the effect of groundwater discharge (characterized by more negative delta D values relative to lake water) and salinity on the delta D values of n-alkanes from P. pectinatus by comparing plants (i) collected from the oligotrophic freshwater Lake Stechlin (Germany) at shallow littoral depth from locations with and without groundwater discharge, and (ii) plants grown from tubers collected from the eutrophic Lake Muggelsee in nutrient solution at four salinity levels. Isotopically depleted groundwater did not have a significant influence on the delta D values of n-alkanes in Lake Stechlin P. pectinatus and calculated isotopic fractionation factors epsilon(l/w) between lake water and n-alkanes averaged -137 +/- 9\%(n-C-23), -136 +/- 7\%(n-C-25) and -131 +/- 6\%(n-C-27), respectively. Similar epsilon values were calculated for plants from Lake Muggelsee grown in freshwater nutrient solution (-134 +/- 11\% for n-C-23), while greater fractionation was observed at increased salinity values of 10 (163 +/- 12\%) and 15(-172 +/- 15\%). We therefore suggest an average e value of -136 +/- 9\% between source water and the major n-alkanes in P. pectinatus grown under freshwater conditions. Our results demonstrate that isotopic fractionation can increase by 30-40\% at salinity values 10 and 15. These results could be explained either by inhibited plant growth at higher salinity, or by metabolic adaptation to salt stress that remain to be elucidated. A potential salinity effect on dD values of aquatic lipids requires further examination, since this would impact on the interpretation of downcore isotopic data in paleohydrologic studies. (C) 2017 Elsevier Ltd. All rights reserved.}, language = {en} } @article{RomeroDiazBreedveldFitze2017, author = {Romero-Diaz, Cristina and Breedveld, Merel Cathelijne and Fitze, Patrick S.}, title = {Climate Effects on Growth, Body Condition, and Survival Depend on the Genetic Characteristics of the Population}, series = {The American naturalist : a bi-monthly journal devoted to the advancement and correlation of the biological sciences}, volume = {190}, journal = {The American naturalist : a bi-monthly journal devoted to the advancement and correlation of the biological sciences}, publisher = {Univ. of Chicago Press}, address = {Chicago}, issn = {0003-0147}, doi = {10.1086/693780}, pages = {649 -- 662}, year = {2017}, abstract = {Climatic change is expected to affect individual life histories and population dynamics, potentially increasing vulnerability to extinction. The importance of genetic diversity has been highlighted for adaptation and population persistence. However, whether responses of life-history traits to a given environmental condition depend on the genetic characteristics of a population remains elusive. Here we tested this hypothesis in the lizard Zootoca vivipara by simultaneously manipulating habitat humidity, a major climatic predictor of Zootoca's distribution, and adult male color morph frequency, a trait with genome-wide linkage. Interactive effects of humidity and morph frequency had immediate effects on growth and body condition of juveniles and yearlings, as well as on adult survival, and delayed effects on offspring size. In yearlings, higher humidity led to larger female body size and lower humidity led to higher male compared to female survival. In juveniles and yearlings, some treatment effects were compensated over time. The results show that individual responses to environmental conditions depend on the population's color morph frequency, age class, and sex and that these affect intra- and inter-age class competition. Moreover, humidity affected the competitive environment rather than imposing trait-based selection on specific color morphs. This indicates that species' responses to changing environments (e.g., to climate change) are highly complex and difficult to accurately reconstruct and predict without information on the genetic characteristics and demographic structure of populations.}, language = {en} } @article{JavanainenMartinezSearaMetzleretal.2017, author = {Javanainen, Matti and Martinez-Seara, Hector and Metzler, Ralf and Vattulainen, Ilpo}, title = {Diffusion of Integral Membrane Proteins in Protein-Rich Membranes}, series = {The journal of physical chemistry letters}, volume = {8}, journal = {The journal of physical chemistry letters}, publisher = {American Chemical Society}, address = {Washington}, issn = {1948-7185}, doi = {10.1021/acs.jpclett.7b01758}, pages = {4308 -- 4313}, year = {2017}, abstract = {The lateral diffusion of embedded proteins along lipid membranes in protein-poor conditions has been successfully described in terms of the Saffman-Delbruck (SD) model, which predicts that the protein diffusion coefficient D is weakly dependent on its radius R as D proportional to ln(1/R). However, instead of being protein-poor, native cell membranes are extremely crowded with proteins. On the basis of extensive molecular simulations, we here demonstrate that protein crowding of the membrane at physiological levels leads to deviations from the SD relation and to the emergence of a stronger Stokes-like dependence D proportional to 1/R. We propose that this 1/R law mainly arises due to geometrical factors: smaller proteins are able to avoid confinement effects much better than their larger counterparts. The results highlight that the lateral dynamics in the crowded setting found in native membranes is radically different from protein-poor conditions and plays a significant role in formation of functional multiprotein complexes.}, language = {en} } @article{SteinhoefelBreuervonBlanckenburgetal.2017, author = {Steinh{\"o}fel, Grit and Breuer, J{\"o}rn and von Blanckenburg, Friedhelm and Horn, Ingo and Sommer, Michael}, title = {The dynamics of Si cycling during weathering in two small catchments in the Black Forest (Germany) traced by Si isotopes}, series = {Chemical geology : official journal of the European Association for Geochemistry}, volume = {466}, journal = {Chemical geology : official journal of the European Association for Geochemistry}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0009-2541}, doi = {10.1016/j.chemgeo.2017.06.026}, pages = {389 -- 402}, year = {2017}, abstract = {Silicon stable isotopes have emerged as a powerful proxy to investigate weathering because Si uptake from solution by secondary minerals or by the vegetation causes significant shifts in the isotope composition. In this study, we determined the Si isotope compositions of the principle Si pools within two small catchments located on sandstone and paragneiss, respectively, in the temperate Black Forest (Germany). At both settings, clay formation is dominated by mineral transformation preserving largely the signature of parental minerals with delta Si-30 values of around -0.7\%. Bulk soils rich in primary minerals are similar to bulk parental material with delta Si-30 values close to -0.4\%. Topsoils are partly different because organic matter degradation has promoted intense weathering leading to delta Si-30 values as low as -1.0\%. Water samples expose highly dynamic weathering processes in the soil zone: 1) after spring snowmelt, increased release of DOC and high water fluxes trigger clay mineral dissolution which leads to delta Si-30 values down to -0.7\% and 2) in course of the summer, Si uptake by the vegetation and secondary mineral formation drives dissolved Si to typical positive delta Si-30 values up to 1.1\%. Groundwater with delta Si-30 values of around 0.4\% records steady processes in bedrock reflecting plagioclase weathering together with kaolinite precipitation. An isotope mass balance approach reveals incongruent weathering conditions where denudation of Si is largely driven by physical erosion. Erosion of phytoliths contributes 3 to 21\% to the total Si export flux, which is in the same order as the dissolved Si flux. These results elucidate the Si dynamics during weathering on catchments underlain of sedimentary origin, prevailing on the Earth surface and provide therefore valuable information to interpret the isotope signature of large river systems.}, language = {en} } @article{ChladkovaHamannWilliamsetal.2017, author = {Chladkova, Katerina and Hamann, Silke and Williams, Daniel and Hellmuth, Sam}, title = {F2 slope as a Perceptual Cue for the Front-Back Contrast in Standard Southern British English}, series = {Language and speech}, volume = {60}, journal = {Language and speech}, publisher = {Sage Publ.}, address = {London}, issn = {0023-8309}, doi = {10.1177/0023830916650991}, pages = {377 -- 398}, year = {2017}, abstract = {Acoustic studies of several languages indicate that second-formant (F2) slopes in high vowels have opposing directions (independent of consonantal context): front [i.]-like vowels are produced with a rising F2 slope, whereas back [u.]-like vowels are produced with a falling F2 slope. The present study first reports acoustic measurements that confirm this pattern for the English variety of Standard Southern British English (SSBE), where /u./ has shifted from the back to the front area of the vowel space and is now realized with higher midpoint F2 values than several decades ago. Subsequently, we test whether the direction of F2 slope also serves as a reliable cue to the /i.// u./ contrast in perception. The findings show that F2 slope direction is used as a cue (additional to midpoint formant values) to distinguish /i./ from /u./by both young and older Standard Southern British English listeners: an otherwise ambiguous token is identified as /i./if it has a rising F2 slope and as /u./if it has a falling F2 slope. Furthermore, our results indicate that listeners generalize their reliance on F2 slope to other contrasts, namely /epsilon/-/./and /ae/-/./, even though F2 slope is not employed to differentiate these vowels in production. This suggests that in Standard Southern British English, a rising F2 seems to be perceptually associated with an abstract feature such as [+ front], whereas a falling F2 with an abstract feature such as [-front].}, language = {en} } @article{BruneCortiRanalli2017, author = {Brune, Sascha and Corti, Giacomo and Ranalli, Giorgio}, title = {Controls of inherited lithospheric heterogeneity on rift linkage: Numerical and analog models of interaction between the Kenyan and Ethiopian rifts across the Turkana depression}, series = {Tectonics}, volume = {36}, journal = {Tectonics}, publisher = {American Geophysical Union}, address = {Washington}, issn = {0278-7407}, doi = {10.1002/2017TC004739}, pages = {1767 -- 1786}, year = {2017}, abstract = {Inherited rheological structures in the lithosphere are expected to have large impact on the architecture of continental rifts. The Turkana depression in the East African Rift connects the Main Ethiopian Rift to the north with the Kenya rift in the south. This region is characterized by a NW-SE trending band of thinned crust inherited from a Mesozoic rifting event, which is cutting the present-day N-S rift trend at high angle. In striking contrast to the narrow rifts in Ethiopia and Kenya, extension in the Turkana region is accommodated in subparallel deformation domains that are laterally distributed over several hundred kilometers. We present both analog experiments and numerical models that reproduce the along-axis transition from narrow rifting in Ethiopia and Kenya to a distributed deformation within the Turkana depression. Similarly to natural observations, our models show that the Ethiopian and Kenyan rifts bend away from each other within the Turkana region, thus forming a right-lateral step over and avoiding a direct link to form a continuous N-S depression. The models reveal five potential types of rift linkage across the preexisting basin: three types where rifts bend away from the inherited structure connecting via a (1) wide or (2) narrow rift or by (3) forming a rotating microplate, (4) a type where rifts bend towards it, and (5) straight rift linkage. The fact that linkage type 1 is realized in the Turkana region provides new insights on the rheological configuration of the Mesozoic rift system at the onset of the recent rift episode. Plain Language Summary The Turkana depression in the Kenya/Ethiopia borderland is most famous for its several million years old human fossils, but it also holds a rich geological history of continental separation. The Turkana region is a lowland located between the East African and Ethiopian domes because its crust and mantle have been stretched in a continent-wide rift event during Cretaceous times about 140-120 Ma ago. This thin lithosphere exerted paramount control on the dynamics of East African rifting in this area, which commenced around 15 Ma ago and persists until today. Combining analog "sandbox" experiments with numerical geodynamic modeling, we find that inherited rift structures explain the dramatic change in rift style from deep, narrow rift basins north and south of the Turkana area to wide, distributed deformation within the Turkana depression. The failed Cretaceous rift is also responsible for the eastward bend of the Ethiopian rift and the westward bend of the Kenyan rift when entering the Turkana depression, which generated the characteristic hook-shaped form of present-day Lake Turkana. Combing two independent modeling techniques-analog and numerical experiments-is a very promising approach allowing to draw robust conclusions about the processes that shape the surface of our planet.}, language = {en} } @article{JapBorleffsMaassen2017, author = {Jap, Bernard A. J. and Borleffs, Elisabeth and Maassen, Ben A. M.}, title = {Towards identifying dyslexia in Standard Indonesian: the development of a reading assessment battery}, series = {Reading and writing : an interdisciplinary journal}, volume = {30}, journal = {Reading and writing : an interdisciplinary journal}, publisher = {Springer}, address = {Dordrecht}, issn = {0922-4777}, doi = {10.1007/s11145-017-9748-y}, pages = {1729 -- 1751}, year = {2017}, language = {en} } @article{RuzanskaWarschburger2017, author = {Ruzanska, Ulrike Alexandra and Warschburger, Petra}, title = {Psychometric evaluation of the German version of the Intuitive Eating Scale-2 in a community sample}, series = {Appetite : multidisciplinary research on eating and drinking}, volume = {117}, journal = {Appetite : multidisciplinary research on eating and drinking}, publisher = {Elsevier}, address = {London}, issn = {0195-6663}, doi = {10.1016/j.appet.2017.06.018}, pages = {126 -- 134}, year = {2017}, language = {en} } @article{AlgharablyBolbrinkerLeziusetal.2017, author = {Algharably, Engi A. H. and Bolbrinker, Juliane and Lezius, Susanne and Reibis, Rona Katharina and Wegscheider, Karl and V{\"o}ller, Heinz and Kreutz, Reinhold}, title = {Uromodulin associates with cardiorenal function in patients with hypertension and cardiovascular disease}, series = {Journal of hypertension}, volume = {35}, journal = {Journal of hypertension}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0263-6352}, doi = {10.1097/HJH.0000000000001432}, pages = {2053 -- 2058}, year = {2017}, abstract = {Objective:Common genetic variants in the gene encoding uromodulin (UMOD) have been associated with renal function, blood pressure (BP) and hypertension. We investigated the associations between an important single nucleotide polymorphism (SNP) in UMOD, that is rs12917707-G>T, and estimated glomerular filtration rate (eGFR), BP and cardiac organ damage as determined by echocardiography in patients with arterial hypertension.Methods:A cohort of 1218 treated high-risk patients (mean age 58.5 years, 83\% men) with documented cardiovascular disease (81\% with coronary heart disease) was analysed.Results:The mean values for 24-h SBP and DBP were 124.714.7 and 73.9 +/- 9.4mmHg; mean eGFR was 77.5 +/- 18.3ml/min per 1.73m(2), mean left ventricular ejection fraction was 59.3 +/- 9.9\% and mean left ventricular mass index in men and women was 53.9 +/- 23.2 and 54.9 +/- 23.7g/m(2.7) with 50.4\% of patients having left ventricular hypertrophy. A significant association between rs12917707 and eGFR was observed with T-allele carriers showing significantly higher eGFR values (+2.6ml/min per 1.73m(2), P=0.006) than noncarriers. This SNP associated also with left atrial diameter (P=0.007); homozygous carriers of the T-allele had smaller left atrial diameter (-1.5mm) than other genotype groups (P=0.040). No significant associations between rs12917707 and other cardiac or BP phenotypes were observed.Conclusions:These findings extend the previously documented role of UMOD for renal function also to treated high-risk patients with arterial hypertension and reveal a novel association with left atrial remodelling and thus a potential cardiorenal link modulated by UMOD.}, language = {en} } @misc{BalkGrijpmaLendlein2017, author = {Balk, Maria and Grijpma, Dirk W. and Lendlein, Andreas}, title = {Design and processing of advanced functional polymers for medicine}, series = {Polymers for advanced technologies}, volume = {28}, journal = {Polymers for advanced technologies}, publisher = {Wiley}, address = {Hoboken}, issn = {1042-7147}, doi = {10.1002/pat.3980}, pages = {1203 -- 1205}, year = {2017}, language = {en} } @article{JanhunenKaminskiOstrowskietal.2017, author = {Janhunen, Tomi and Kaminski, Roland and Ostrowski, Max and Schellhorn, Sebastian and Wanko, Philipp and Schaub, Torsten H.}, title = {Clingo goes linear constraints over reals and integers}, series = {Theory and practice of logic programming}, volume = {17}, journal = {Theory and practice of logic programming}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {1471-0684}, doi = {10.1017/S1471068417000242}, pages = {872 -- 888}, year = {2017}, abstract = {The recent series 5 of the Answer Set Programming (ASP) system clingo provides generic means to enhance basic ASP with theory reasoning capabilities. We instantiate this framework with different forms of linear constraints and elaborate upon its formal properties. Given this, we discuss the respective implementations, and present techniques for using these constraints in a reactive context. More precisely, we introduce extensions to clingo with difference and linear constraints over integers and reals, respectively, and realize them in complementary ways. Finally, we empirically evaluate the resulting clingo derivatives clingo[dl] and clingo[lp] on common language fragments and contrast them to related ASP systems.}, language = {en} } @article{PalyulinMantsevichKlagesetal.2017, author = {Palyulin, Vladimir V. and Mantsevich, Vladimir N. and Klages, Rainer and Metzler, Ralf and Chechkin, Aleksei V.}, title = {Comparison of pure and combined search strategies for single and multiple targets}, series = {The European physical journal : B, Condensed matter and complex systems}, volume = {90}, journal = {The European physical journal : B, Condensed matter and complex systems}, publisher = {Springer}, address = {New York}, issn = {1434-6028}, doi = {10.1140/epjb/e2017-80372-4}, pages = {20 -- 37}, year = {2017}, abstract = {We address the generic problem of random search for a point-like target on a line. Using the measures of search reliability and efficiency to quantify the random search quality, we compare Brownian search with Levy search based on long-tailed jump length distributions. We then compare these results with a search process combined of two different long-tailed jump length distributions. Moreover, we study the case of multiple targets located by a Levy searcher.}, language = {en} } @article{ScheelHoeppnerGrotevendtetal.2017, author = {Scheel, Tabea and Hoeppner, Dorothea and Grotevendt, Anne and Barthlen, Winfried}, title = {Clowns in Paediatric Surgery: Less Anxiety and More Oxytocin? A Pilot Study}, series = {Klinische P{\"a}diatrie : clinical research and practice in pediatrics}, volume = {229}, journal = {Klinische P{\"a}diatrie : clinical research and practice in pediatrics}, publisher = {Thieme}, address = {Stuttgart}, issn = {0300-8630}, doi = {10.1055/s-0043-106854}, pages = {274 -- 280}, year = {2017}, abstract = {Background Hospital stays and medical interventions are accompanied by worries and anxiety in children and parents. Recent studies show that hospital clowns may reduce anxiety and enhance well-being. However, so far studies are based solely on subjective measures and clowns are usually not integrated in medical routine. With this pilot study, we aim to provide both psychological and physiological evidence of positive effects of clowns' interventions in hospitalized children. Patients/Method In a consecutive randomized intervention-control group design with 31 children aged 4 to 13 years, 17 patients were accompanied by a clown prior to surgery or during ward round (intervention group) and 14 were not (control group). Saliva samples for oxytocin measurement were taken from all patients before hospitalization (T1) and prior to surgery or after ward round (T2). Self- and parents-reports were obtained at T1, T2 as well as at time of discharge from hospital (T3) regarding children's anxiety (STAI), worries and well-being. Clowns evaluated their success in cheering up the child. Health professionals were asked for their acceptance of clowns in hospitals. Results Children in the intervention group had lower anxiety ratings and a higher oxytocin concentration at T2 as compared with T1; the control group showed no changes. Parents rated the well-being of their children higher if their child had clown's contact and were more willing to recommend the hospital. The staff judged the clowns as helpful for patients. Discussion Consistent psychological and physiological results suggest the positive impact of a clown's intervention in hospitalized children.}, language = {en} } @article{FudickarLinker2017, author = {Fudickar, Werner and Linker, Torsten}, title = {Synthesis of Pyridylanthracenes and Their Reversible Reaction with Singlet Oxygen to Endoperoxides}, series = {The journal of organic chemistry}, volume = {82}, journal = {The journal of organic chemistry}, publisher = {American Chemical Society}, address = {Washington}, issn = {0022-3263}, doi = {10.1021/acs.joc.7b01765}, pages = {9258 -- 9262}, year = {2017}, abstract = {The ortho, meta, and para isomers of 9,10-dipyridylanthracene 1 have been synthesized and converted into their endoperoxides 1-O-2 upon oxidation with singlet oxygen. The kinetics of this reaction can be controlled by the substitution pattern and the solvent: in highly polar solvents, the meta isomer is the most reactive, whereas the ortho isomer is oxidized fastest in nonpolar solvents. Heating of the endoperoxides affords the parent anthracenes by release of singlet oxygen.}, language = {en} } @article{BauchKrtitschkaLinker2017, author = {Bauch, Marcel and Krtitschka, Angela and Linker, Torsten}, title = {Photooxygenation of oxygen-substituted naphthalenes}, series = {Journal of physical organic chemistry}, volume = {30}, journal = {Journal of physical organic chemistry}, publisher = {Wiley}, address = {Hoboken}, issn = {0894-3230}, doi = {10.1002/poc.3734}, pages = {6803 -- 6813}, year = {2017}, abstract = {The reaction of oxygen-substituted naphthalenes with singlet oxygen (O-1(2)) has been investigated, and labile endoperoxides have been isolated and characterized at -78 degrees C for the first time. Low-temperature kinetics by UV spectroscopy revealed that alkoxy and silyloxy substituents remarkably increase the rate of photooxygenations compared to 1,4-dimethylnaphthalene, whereas acyloxy-substituted acenes are inert towards O-1(2). The reactivities nicely correlate with HOMO energies and free activation energies, which we determined by density functional theory calculations. The lability of the isolated endoperoxides is due to their very fast back reaction to the corresponding naphthalenes even at -20 degrees C under release of O-1(2), making them to superior sources of this reactive species under very mild conditions. Finally, a carbohydrate-substituted naphthalene has been synthesized, which reacts reversibly with O-1(2) and might be applied for enantioselective oxidations in future work.}, language = {en} } @misc{IhmelsLinkerTrofimov2017, author = {Ihmels, Heiko and Linker, Torsten and Trofimov, Aleksei}, title = {Editorial}, series = {Journal of physical organic chemistry}, volume = {30}, journal = {Journal of physical organic chemistry}, publisher = {Wiley}, address = {Hoboken}, issn = {0894-3230}, doi = {10.1002/poc.3745}, pages = {1}, year = {2017}, language = {en} } @article{SimikWierzba2017, author = {Simik, Radek and Wierzba, Marta}, title = {EXPRESSION OF INFORMATION STRUCTURE IN WEST SLAVIC: MODELING THE IMPACT OF PROSODIC AND WORD-ORDER FACTORS}, series = {Language : journal of the Linguistic Society of America}, volume = {93}, journal = {Language : journal of the Linguistic Society of America}, publisher = {Linguistic Society of America}, address = {Washington}, issn = {0097-8507}, doi = {10.1353/lan.2017.0040}, pages = {671 -- 709}, year = {2017}, abstract = {The received wisdom is that word-order alternations in Slavic languages arise as a direct consequence of word-order-related information-structure constraints such as 'Place given expressions before new ones'. In this article, we compare the word-order hypothesis with a competing one, according to which word-order alternations arise as a consequence of a prosodic constraint: 'Avoid stress on given expressions'. Based on novel experimental and modeling data, we conclude that the prosodic hypothesis is more adequate than the word-order hypothesis. Yet we also show that combining the strengths of both hypotheses provides the best fit for the data. Methodologically, our article is based on gradient acceptability judgments and multiple regression, which allows us to evaluate whether violations of generalizations like 'Given precedes new' or 'Given lacks stress' lead to a consistent decrease in acceptability and to quantify the size of their respective effects. Focusing on the empirical adequacy of such generalizations rather than on specific theoretical implementations also makes it possible to bridge the gap between different linguistic traditions and to directly compare predictions emerging from formal and functional approaches.}, language = {en} } @article{FlaschvonElmWester2017, author = {Flasch, Leopold and von Elm, Natalie and Wester, Petra}, title = {Nectar-drinking Elephantulus edwardii as a potential pollinator of Massonia echinata, endemic to the Bokkeveld plateau in South Africa}, series = {African journal of ecology}, volume = {55}, journal = {African journal of ecology}, publisher = {Wiley}, address = {Hoboken}, issn = {0141-6707}, doi = {10.1111/aje.12352}, pages = {376 -- 379}, year = {2017}, language = {en} } @article{RyabchunSakhnoStumpeetal.2017, author = {Ryabchun, Alexander and Sakhno, Oksana and Stumpe, Joachim and Bobrovsky, Alexey}, title = {Full-Polymer Cholesteric Composites for Transmission and Reflection Holographic Gratings}, series = {Advanced optical materials}, volume = {5}, journal = {Advanced optical materials}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {2195-1071}, doi = {10.1002/adom.201700314}, pages = {376 -- 379}, year = {2017}, abstract = {A new type of self-organized materials based on cholesteric networks filled with photoactive side-chain copolymer is being developed. Supramolecular helical structure of cholesteric polymer network resulting in the selective reflection is used as a photonic scaffold. Photochromic azobenzene-containing nematic copolymer is embedded in cholesteric scaffold and utilized as a photoactive media for optical pattering. 1D and 2D transmission diffraction gratings are successfully recorded in composite films by holographic technique. For the first time the possibility to create selective reflection gratings in cholesteric material mimicking the natural optical properties of cholesteric mesophase is demonstrated. That enables the coexistence of two selective gratings, where one has an intrinsic cholesteric periodic helical structure and the other is a holographic grating generated in photochromic polymer. The full-polymer composites provide high light-induced optical anisotropy due to effective photo-orientation of side-chain fragments of the azobenzene-containing liquid crystalline polymer, and prevent the degradation of the helical superstructure maintaining all optical properties of cholesteric mesophase. The proposed class of optical materials could be easily applied to a broad range of polymeric materials with specific functionality. The versatility of the adjustment and material preprogramming combined with high optical performance makes these materials a highly promising candidate for modern optical and photonic applications.}, language = {en} } @article{BoersGoswamiGhil2017, author = {Boers, Niklas and Goswami, Bedartha and Ghil, Michael}, title = {A complete representation of uncertainties in layer-counted paleoclimatic archives}, series = {Climate of the past : an interactive open access journal of the European Geosciences Union}, volume = {13}, journal = {Climate of the past : an interactive open access journal of the European Geosciences Union}, publisher = {Copernicus}, address = {G{\"o}ttingen}, issn = {1814-9324}, doi = {10.5194/cp-13-1169-2017}, pages = {12}, year = {2017}, abstract = {Accurate time series representation of paleoclimatic proxy records is challenging because such records involve dating errors in addition to proxy measurement errors. Rigorous attention is rarely given to age uncertainties in paleoclimatic research, although the latter can severely bias the results of proxy record analysis. Here, we introduce a Bayesian approach to represent layer-counted proxy records - such as ice cores, sediments, corals, or tree rings - as sequences of probability distributions on absolute, error-free time axes. The method accounts for both proxy measurement errors and uncertainties arising from layer-counting-based dating of the records. An application to oxygen isotope ratios from the North Greenland Ice Core Project (NGRIP) record reveals that the counting errors, although seemingly small, lead to substantial uncertainties in the final representation of the oxygen isotope ratios. In particular, for the older parts of the NGRIP record, our results show that the total uncertainty originating from dating errors has been seriously underestimated. Our method is next applied to deriving the overall uncertainties of the Suigetsu radiocarbon comparison curve, which was recently obtained from varved sediment cores at Lake Suigetsu, Japan. This curve provides the only terrestrial radiocarbon comparison for the time interval 12.5-52.8 kyr BP. The uncertainties derived here can be readily employed to obtain complete error estimates for arbitrary radiometrically dated proxy records of this recent part of the last glacial interval.}, language = {en} } @article{RachEngelsKahmenetal.2017, author = {Rach, Oliver and Engels, S. and Kahmen, A. and Brauer, Achim and Martin-Puertas, C. and van Geel, B. and Sachse, Dirk}, title = {Hydrological and ecological changes in western Europe between 3200 and 2000 years BP derived from lipid biomarker delta D values in lake Meerfelder Maar sediments}, series = {Quaternary science reviews : the international multidisciplinary research and review journal}, volume = {172}, journal = {Quaternary science reviews : the international multidisciplinary research and review journal}, publisher = {Elsevier}, address = {Oxford}, issn = {0277-3791}, doi = {10.1016/j.quascirev.2017.07.019}, pages = {44 -- 54}, year = {2017}, abstract = {One of the most significant Late Holocene climate shifts occurred around 2800 years ago, when cooler and wetter climate conditions established in western Europe. This shift coincided with an abrupt change in regional atmospheric circulation between 2760 and 2560 cal years BP, which has been linked to a grand solar minimum with the same duration (the Homeric Minimum). We investigated the temporal sequence of hydroclimatic and vegetation changes across this interval of climatic change (Homeric climate oscillation) by using lipid biomarker stable hydrogen isotope ratios (ED values) and pollen assemblages from the annually-laminated sediment record from lake Meerfelder Maar (Germany). Over the investigated interval (3200-2000 varve years BP), terrestrial lipid biomarker ED showed a gradual trend to more negative values, consistent with the western Europe long-term climate trend of the Late Holocene. At ca. 2640 varve years BP we identified a strong increase in aquatic plants and algal remains, indicating a rapid change in the aquatic ecosystem superimposed on this long-term trend. Interestingly, this aquatic ecosystem change was accompanied by large changes in ED values of aquatic lipid biomarkers, such as nC(21) and nC(23) (by between 22 and 30\%(0)). As these variations cannot solely be explained by hydroclimate changes, we suggest that these changes in the Wag value were influenced by changes in n-alkane source organisms. Our results illustrate that if ubiquitous aquatic lipid biomarkers are derived from a limited pool of organisms, changes in lake ecology can be a driving factor for variations on sedimentary lipid MN values, which then could be easily misinterpreted in terms of hydro climatic changes. (C) 2017 Elsevier Ltd. All rights reserved.}, language = {en} } @article{CaetanodeCarvalhoMetzleretal.2017, author = {Caetano, Daniel L. Z. and de Carvalho, Sidney J. and Metzler, Ralf and Cherstvy, Andrey G.}, title = {Critical adsorption of periodic and random polyampholytes onto charged surfaces}, series = {Physical chemistry, chemical physics : a journal of European Chemical Societies}, volume = {19}, journal = {Physical chemistry, chemical physics : a journal of European Chemical Societies}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {1463-9076}, doi = {10.1039/c7cp04040g}, pages = {23397 -- 23413}, year = {2017}, abstract = {How different are the properties of critical adsorption of polyampholytes and polyelectrolytes onto charged surfaces? How important are the details of polyampholyte charge distribution on the onset of critical adsorption transition? What are the scaling relations governing the dependence of critical surface charge density on salt concentration in the surrounding solution? Here, we employ Metropolis Monte Carlo simulations and uncover the scaling relations for critical adsorption for quenched periodic and random charge distributions along the polyampholyte chains. We also evaluate and discuss the dependence of the adsorbed layer width on solution salinity and details of the charge distribution. We contrast our findings to the known results for polyelectrolyte adsorption onto oppositely charged surfaces, in particular, their dependence on electrolyte concentration.}, language = {en} } @article{MuenchKipfstuhlFreitagetal.2017, author = {Muench, Thomas and Kipfstuhl, Sepp and Freitag, Johannes and Meyer, Hanno and Laepple, Thomas}, title = {Constraints on post-depositional isotope modifications in East Antarctic firn from analysing temporal changes of isotope profiles}, series = {The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union}, volume = {11}, journal = {The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union}, publisher = {Copernicus}, address = {G{\"o}ttingen}, issn = {1994-0416}, doi = {10.5194/tc-11-2175-2017}, pages = {2175 -- 2188}, year = {2017}, abstract = {The isotopic composition of water in ice sheets is extensively used to infer past climate changes. In low-accumulation regions their interpretation is, however, challenged by poorly constrained effects that may influence the initial isotope signal during and after deposition of the snow. This is reflected in snow-pit isotope data from Kohnen Station, Antarctica, which exhibit a seasonal cycle but also strong interannual variations that contradict local temperature observations. These inconsistencies persist even after averaging many profiles and are thus not explained by local stratigraphic noise. Previous studies have suggested that post-depositional processes may significantly influence the isotopic composition of East Antarctic firn. Here, we investigate the importance of post-depositional processes within the open-porous firn (greater than or similar to 10 cm depth) at Kohnen Station by separating spatial from temporal variability. To this end, we analyse 22 isotope profiles obtained from two snow trenches and examine the temporal isotope modifications by comparing the new data with published trench data extracted 2 years earlier. The initial isotope profiles undergo changes over time due to downward advection, firn diffusion and densification in magnitudes consistent with independent estimates. Beyond that, we find further modifications of the original isotope record to be unlikely or small in magnitude (<< 1 parts per thousand RMSD). These results show that the discrepancy between local temperatures and isotopes most likely originates from spatially coherent processes prior to or during deposition, such as precipitation intermittency or systematic isotope modifications acting on drifting or loose surface snow.}, language = {en} } @article{RubeyBruneHeineetal.2017, author = {Rubey, Michael and Brune, Sascha and Heine, Christian and Davies, D. Rhodri and Williams, Simon E. and M{\"u}ller, R. Dietmar}, title = {role of subducted slabs}, series = {Solid earth}, volume = {8}, journal = {Solid earth}, publisher = {Copernicus}, address = {G{\"o}ttingen}, issn = {1869-9510}, doi = {10.5194/se-8-899-2017}, pages = {899 -- 919}, year = {2017}, language = {en} } @article{StarkenburgMartinYouakimetal.2017, author = {Starkenburg, Else and Martin, Nicolas and Youakim, Kris and Aguado, David S. and Allende Prieto, Carlos and Arentsen, Anke and Bernard, Edouard J. and Bonifacio, Piercarlo and Caffau, Elisabetta and Carlberg, Raymond G. and Cote, Patrick and Fouesneau, Morgan and Francois, Patrick and Franke, Oliver and Gonzalez Hernandez, Jonay I. and Gwyn, Stephen D. J. and Hill, Vanessa and Ibata, Rodrigo A. and Jablonka, Pascale and Longeard, Nicolas and McConnachie, Alan W. and Navarro, Julio F. and Sanchez-Janssen, Ruben and Tolstoy, Eline and Venn, Kim A.}, title = {The Pristine survey - I. Mining the Galaxy for the most metal-poor stars}, series = {Monthly notices of the Royal Astronomical Society}, volume = {471}, journal = {Monthly notices of the Royal Astronomical Society}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/stx1068}, pages = {2587 -- 2604}, year = {2017}, abstract = {We present the Pristine survey, a new narrow-band photometric survey focused on the metallicity-sensitive Ca H\&K lines and conducted in the Northern hemisphere with the wide-field imager MegaCam on the Canada-France-Hawaii Telescope. This paper reviews our overall survey strategy and discusses the data processing and metallicity calibration. Additionally we review the application of these data to the main aims of the survey, which are to gather a large sample of the most metal-poor stars in the Galaxy, to further characterize the faintest Milky Way satellites, and to map the (metal-poor) substructure in the Galactic halo. The current Pristine footprint comprises over 1000 deg(2) in the Galactic halo ranging from b similar to 30 degrees to similar to 78 degrees and covers many known stellar substructures. We demonstrate that, for Sloan Digital Sky Survey (SDSS) stellar objects, we can calibrate the photometry at the 0.02-mag level. The comparison with existing spectroscopic metallicities from SDSS/Sloan Extension for Galactic Understanding and Exploration (SEGUE) and Large Sky Area Multi-Object Fiber Spectroscopic Telescope shows that, when combined with SDSS broad-band g and i photometry, we can use the CaHK photometry to infer photometric metallicities with an accuracy of similar to 0.2 dex from [Fe/H] = -0.5 down to the extremely metal-poor regime ([Fe/H] < -3.0). After the removal of various contaminants, we can efficiently select metal-poor stars and build a very complete sample with high purity. The success rate of uncovering [Fe/H](SEGUE) < -3.0 stars among [Fe/H](Pristine) < -3.0 selected stars is 24 per cent, and 85 per cent of the remaining candidates are still very metal poor ([Fe/H]<-2.0). We further demonstrate that Pristine is well suited to identify the very rare and pristine Galactic stars with [Fe/H] < -4.0, which can teach us valuable lessons about the early Universe.}, language = {en} } @article{Buerger2017, author = {B{\"u}rger, Gerhard}, title = {On trend detection}, series = {Hydrological processes}, volume = {31}, journal = {Hydrological processes}, publisher = {Wiley}, address = {Hoboken}, issn = {0885-6087}, doi = {10.1002/hyp.11280}, pages = {4039 -- 4042}, year = {2017}, abstract = {A main obstacle to trend detection in time series occurs when they are autocorrelated. By reducing the effective sample size of a series, autocorrelation leads to decreased trend significance. Numerous recipes attempt to mitigate the effect of autocorrelation, either by adjusting for the reduced effective sample size or by removing the autocorrelated components of a series. This short note deals with the latter, also called prewhitening (PW). It is known that removal of autocorrelation also removes part of the trend, which may affect the signal-to-noise ratio. Two popular methods have dealt with this problem, the trend-free prewhitening (TFPW) and the iterative prewhitening. Although it is generally accepted that both methods reduce the adverse effects of PW on the trend magnitude, corresponding effects on statistical significance have not been clearly stated for TFPW. Using a Monte Carlo approach, it is demonstrated that both methods entail quite different Type-I error rates. The iterative prewhitening produces rates that are generally close to the nominal significance level. The TFPW, however, shows very high Type-I error rates with increasing autocorrelation. The corresponding rate of false trend detections is unacceptable for applications, so that published trends based on TFPW need to be reassessed.}, language = {en} } @misc{ErraVelazquezRosenblum2017, author = {Erra, Ramon Guevara and Velazquez, Jose L. Perez and Rosenblum, Michael}, title = {Neural Synchronization from the Perspective of Non-linear Dynamics}, series = {Frontiers in computational neuroscience / Frontiers Research Foundation}, volume = {11}, journal = {Frontiers in computational neuroscience / Frontiers Research Foundation}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1662-5188}, doi = {10.3389/fncom.2017.00098}, pages = {4}, year = {2017}, language = {en} } @article{NazarovaBleibtreuHoffetal.2017, author = {Nazarova, Larisa B. and Bleibtreu, Annette and Hoff, Ulrike and Dirksen, Veronika and Diekmann, Bernhard}, title = {Changes in temperature and water depth of a small mountain lake during the past 3000 years in Central Kamchatka reflected by a chironomid record}, series = {Quaternary international : the journal of the International Union for Quaternary Research}, volume = {447}, journal = {Quaternary international : the journal of the International Union for Quaternary Research}, publisher = {Elsevier}, address = {Oxford}, issn = {1040-6182}, doi = {10.1016/j.quaint.2016.10.008}, pages = {46 -- 58}, year = {2017}, abstract = {We investigated chironomid assemblages of a well-dated sediment core from a small seepage lake situated at the eastern slope of the Central Kamchatka Mountain Chain, Far East Russia. The chironomid fauna of the investigated Sigrid Lake is dominated by littoral taxa that are sensitive to fluctuations of the water level. Two groups of taxa interchangeably dominate the record responding to the changes in the lake environment during the past 2800 years. The first group of littoral phytophilic taxa includes Psectrocladius sordidellus-type, Corynoneura arctica-type and Dicrotendipes nervosus-type. The abundances of the taxa from this group have the strongest influence on the variations of PCA 1, and these taxa mostly correspond to low water levels, moderate temperatures and slightly acidified conditions. The second group of taxa includes Microtendipes pedellus-type, Tanytarsus lugens-type, and Tanytarsus pallidicornistype. The variations in the abundances of these taxa, and especially of M. pedellus-type, are in accordance with PCA 2 and correspond to the higher water level in the lake, more oligotrophic and neutral pH conditions. Water depths (WD) were reconstructed, using a modern chironomid-based temperature and water depth calibration data set (training set) and inference model from East Siberia (Nazarova et al., 2011). Mean July air temperatures (T July) were inferred using a chironomid-based temperature inference model based on a modern calibration data set for the Far East (Nazarova et al., 2015). The application of transfer functions resulted in reconstructed T July fluctuations of approximately 3 degrees C over the last 2800 years. Low temperatures (11.0-12.0 degrees C) were reconstructed for the periods between ca 1700 and 1500 cal yr BP (corresponding to the Kofun cold stage) and between ca 1200 and 150 cal yr BP (partly corresponding to the Little Ice Age [LIA]). Warm periods (modern T July or higher) were reconstructed for the periods between ca 2700 and 1800 cal yr BP, 1500 and 1300 cal yr BP and after 150 cal yr BP. WD reconstruction revealed that the lake level was lower than its present level at the beginning of the record between ca 2600 and 2300 cal yr BP and ca 550 cal yr BP. Between ca 2300 and 700 cal yr BP as well as between 450 and 150 cal yr BP, the lake level was higher than it is today, most probably reflecting more humid conditions. (C) 2016 Elsevier Ltd and INQUA. All rights reserved.}, language = {en} } @article{ThammSchollReimetal.2017, author = {Thamm, Markus and Scholl, Christina and Reim, Tina and Gruebel, Kornelia and Moeller, Karin and Rossler, Wolfgang and Scheiner, Ricarda}, title = {Neuronal distribution of tyramine and the tyramine receptor AmTAR1 in the honeybee brain}, series = {The journal of comparative neurology}, volume = {525}, journal = {The journal of comparative neurology}, publisher = {Wiley}, address = {Hoboken}, issn = {0021-9967}, doi = {10.1002/cne.24228}, pages = {2615 -- 2631}, year = {2017}, abstract = {Tyramine is an important neurotransmitter, neuromodulator, and neurohormone in insects. In honeybees, it is assumed to have functions in modulating sensory responsiveness and controlling motor behavior. Tyramine can bind to two characterized receptors in honeybees, both of which are coupled to intracellular cAMP pathways. How tyramine acts on neuronal, cellular and circuit levels is unclear. We investigated the spatial brain expression of the tyramine receptor AmTAR1 using a specific antibody. This antibody detects a membrane protein of the expected molecular weight in western blot analysis. In honeybee brains, it labels different structures which process sensory information. Labeling along the antennal nerve, in projections of the dorsal lobe and in the gnathal ganglion suggest that tyramine receptors are involved in modulating gustatory and tactile perception. Furthermore, the ellipsoid body of the central complex and giant synapses in the lateral complex show AmTAR1-like immunoreactivity (AmTAR1-IR), suggesting a role of this receptor in modulating sky-compass information and/or higher sensor-motor control. Additionally, intense signals derive from the mushroom bodies, higher-order integration centers for olfactory, visual, gustatory and tactile information. To investigate whether AmTAR1-expressing brain structures are in vicinity to tyramine releasing sites, a specific tyramine antibody was applied. Tyramine-like labeling was observed in AmTAR1-IR positive structures, although it was sometimes weak and we did not always find a direct match of ligand and receptor. Moreover, tyramine-like immunoreactivity was also found in brain regions without AmTAR1-IR (optic lobes, antennal lobes), indicating that other tyramine-specific receptors may be expressed there.}, language = {en} } @article{AroraMawassSandigetal.2017, author = {Arora, Ashima and Mawass, Mohamad-Assaad and Sandig, Oliver and Luo, Chen and Uenal, Ahmet A. and Radu, Florin and Valencia, Sergio and Kronast, Florian}, title = {Spatially resolved investigation of all optical magnetization switching in TbFe alloys}, series = {Scientific reports}, volume = {7}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-017-09615-1}, pages = {9}, year = {2017}, abstract = {Optical control of magnetization using femtosecond laser without applying any external magnetic field offers the advantage of switching magnetic states at ultrashort time scales. Recently, all-optical helicity-dependent switching (AO-HDS) has drawn a significant attention for potential information and data storage device applications. In this work, we employ element and magnetization sensitive photoemission electron microscopy (PEEM) to investigate the role of heating in AO-HDS for thin films of the rare-earth transition-metal alloy TbFe. Spatially resolved measurements in a 3-5\&\#8201;\&\#956;m sized stationary laser spot demonstrate that AO-HDS is a local phenomenon in the vicinity of thermal demagnetization in a 'ring' shaped region. The efficiency of AO-HDS further depends on a local temperature profile around the demagnetized region and thermally activated domain wall motion. We also demonstrate that the thickness of the film determines the preferential switching direction for a particular helicity.}, language = {en} } @article{ZengLeimkuehlerWollenbergeretal.2017, author = {Zeng, Ting and Leimk{\"u}hler, Silke and Wollenberger, Ulla and Fourmond, Vincent}, title = {Transient Catalytic Voltammetry of Sulfite Oxidase Reveals Rate Limiting Conformational Changes}, series = {Journal of the American Chemical Society}, volume = {139}, journal = {Journal of the American Chemical Society}, publisher = {American Chemical Society}, address = {Washington}, issn = {0002-7863}, doi = {10.1021/jacs.7b05480}, pages = {11559 -- 11567}, year = {2017}, abstract = {Sulfite oxidases are metalloenzymes that oxidize sulfite to sulfate at a molybdenum active site. In vertebrate sulfite oxidases, the electrons generated at the Mo center are transferred to an external electron acceptor via a heme domain, which can adopt two conformations: a "closed" conformation, suitable for internal electron transfer, and an "open" conformation suitable for intermolecular electron transfer. This conformational change is an integral part of the catalytic cycle. Sulfite oxidases have been wired to electrode surfaces, but their immobilization leads to a significant decrease in their catalytic activity, raising the question of the occurrence of the conformational change when the enzyme is on an electrode. We recorded and quantitatively modeled for the first time the transient response of the catalytic cycle of human sulfite oxidase immobilized on an electrode. We show that conformational changes still occur on the electrode, but at a lower rate than in solution, which is the reason for the decrease in activity of sulfite oxidases upon immobilization.}, language = {en} } @article{MorHerzogGolezetal.2017, author = {Mor, Selene and Herzog, Marc and Golez, Denis and Werner, Philipp and Eckstein, Martin and Katayama, Naoyuki and Nohara, Minoru and Takagi, Hide and Mizokawa, Takashi and Monney, Claude and Staehler, Julia}, title = {Ultrafast Electronic Band Gap Control in an Excitonic Insulator}, series = {Physical review letters}, volume = {119}, journal = {Physical review letters}, publisher = {American Physical Society}, address = {College Park}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.119.086401}, pages = {11559 -- 11567}, year = {2017}, abstract = {We report on the nonequilibrium dynamics of the electronic structure of the layered semiconductor Ta2NiSe5 investigated by time-and angle-resolved photoelectron spectroscopy. We show that below the critical excitation density of F-C = 0.2 mJ cm(-2), the band gap narrows transiently, while it is enhanced above FC. Hartree-Fock calculations reveal that this effect can be explained by the presence of the low-temperature excitonic insulator phase of Ta2NiSe5, whose order parameter is connected to the gap size. This work demonstrates the ability to manipulate the band gap of Ta2NiSe5 with light on the femtosecond time scale.}, language = {en} } @article{NinausMoellerKaufmannetal.2017, author = {Ninaus, Manuel and Moeller, Korbinian and Kaufmann, Liane and Fischer, Martin H. and Nuerk, Hans-Christoph and Wood, Guilherme}, title = {Cognitive Mechanisms Underlying Directional and Non-directional Spatial-Numerical Associations across the Lifespan}, series = {Frontiers in psychology}, volume = {8}, journal = {Frontiers in psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2017.01421}, pages = {13}, year = {2017}, abstract = {There is accumulating evidence suggesting an association of numbers with physical space. However, the origin of such spatial-numerical associations (SNAs) is still debated. In the present study we investigated the development of two SNAs in a cross-sectional study involving children, young and middle-aged adults as well as the elderly: (1) the SNARC (spatial-numerical association of response codes) effect, reflecting a directional SNA; and (2) the numerical bisection bias in a line bisection task with numerical flankers. Results revealed a consistent SNARC effect in all age groups that continuously increased with age. In contrast, a numerical bisection bias was only observed for children and elderly participants, implying an U-shaped distribution of this bias across age groups. Additionally, individual SNARC effects and numerical bisection biases did not correlate significantly. We argue that the SNARC effect seems to be influenced by longer-lasting experiences of cultural constraints such as reading and writing direction and may thus reflect embodied representations. Contrarily, the numerical bisection bias may originate from insufficient inhibition of the semantic influence of irrelevant numerical flankers, which should be more pronounced in children and elderly people due to development and decline of cognitive control, respectively. As there is an ongoing debate on the origins of SNAs in general and the SNARC effect in particular, the present results are discussed in light of these differing accounts in an integrative approach. However, taken together, the present pattern of results suggests that different cognitive mechanisms underlie the SNARC effect and the numerical bisection bias.}, language = {en} } @article{NegiPaulCescaetal.2017, author = {Negi, Sanjay S. and Paul, Ajay and Cesca, Simone and Kamal, and Kriegerowski, Marius and Mahesh, P. and Gupta, Sandeep}, title = {Crustal velocity structure and earthquake processes of Garhwal-Kumaun Himalaya: Constraints from regional waveform inversion and array beam modeling}, series = {Tectonophysics : international journal of geotectonics and the geology and physics of the interior of the earth}, volume = {712}, journal = {Tectonophysics : international journal of geotectonics and the geology and physics of the interior of the earth}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0040-1951}, doi = {10.1016/j.tecto.2017.05.007}, pages = {45 -- 63}, year = {2017}, abstract = {In order to understand present day earthquake kinematics at the Indian plate boundary, we analyse seismic broadband data recorded between 2007 and 2015 by the regional network in the Garhwal-Kumaun region, northwest Himalaya. We first estimate a local 1-D velocity model for the computation of reliable Green's functions, based on 2837 P-wave and 2680 S-wave arrivals from 251 well located earthquakes. The resulting 1-D crustal structure yields a 4-layer velocity model down to the depths of 20 km. A fifth homogeneous layer extends down to 46 km, constraining the Moho using travel-time distance curve method. We then employ a multistep moment tensor (MT) inversion algorithm to infer seismic moment tensors of 11 moderate earthquakes with Mw magnitude in the range 4.0-5.0. The method provides a fast MT inversion for future monitoring of local seismicity, since Green's functions database has been prepared. To further support the moment tensor solutions, we additionally model P phase beams at seismic arrays at teleseismic distances. The MT inversion result reveals the presence of dominant thrust fault kinematics persisting along the Himalayan belt. Shallow low and high angle thrust faulting is the dominating mechanism in the Garhwal-Kumaun Himalaya. The centroid depths for these moderate earthquakes are shallow between 1 and 12 km. The beam modeling result confirm hypocentral depth estimates between 1 and 7 km. The updated seismicity, constrained source mechanism and depth results indicate typical setting of duplexes above the mid crustal ramp where slip is confirmed along out-of-sequence thrusting. The involvement of Tons thrust sheet in out-of-sequence thrusting indicate Tons thrust to be the principal active thrust at shallow depth in the Himalayan region. Our results thus support the critical taper wedge theory, where we infer the microseismicity cluster as a result of intense activity within the Lesser Himalayan Duplex (LHD) system.}, language = {en} } @article{GoetzChmielewskiGoedekeetal.2017, author = {Goetz, Klaus-Peter and Chmielewski, Frank M. and Goedeke, Kristin and Wolf, Kristine and Jander, Elisabeth and Sievers, Steven and Homann, Thomas and Huschek, Gerd and Rawel, Harshadrai Manilal}, title = {Assessment of amino acids during winter rest and ontogenetic development in sweet cherry buds (Prunus avium. L.)}, series = {Scientia horticulturae : an international journal sponsored by the International Society for Horticultural Science}, volume = {222}, journal = {Scientia horticulturae : an international journal sponsored by the International Society for Horticultural Science}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0304-4238}, doi = {10.1016/j.scienta.2017.05.001}, pages = {102 -- 110}, year = {2017}, abstract = {This study examined changes in sweet cherry buds of 'Summit' cultivar in four seasons (2011/12-2014/15) with respect to the nitrogen (N) content and the profile of eight free amino acids (asparagine (Asn), aspartic acid (Asp), isoleucine (Ile), glutamine (Gln), glutamic acid (Glu), arginine (Arg), alanine (Ala), histidine (His)). The presented results are to our knowledge the first under natural conditions in fruit tree orchards with a high temporal resolution from the dormant stage until cluster development. The N content in the buds from October, during endo- and ecodormancy until the beginning of ontogenetic development was a relatively stable parameter in each of the four seasons. The N accumulation into the buds began after 'swollen bud' and significant differences were visible at 'green tip' with an N content of 3.24, 3.12, 3.08, 2.40 which increased markedly to the mean of 'tight' and 'open cluster' by 3.77\%, 3.78\%, 3.44\% and 3.10\% in 2012-2015, respectively. In the buds, levels of asparagine were higher (up to 44 mg g\&\#8722;1 DW\&\#8722;1) than aspartic acid (up to 2 mg g\&\#8722;1 DW\&\#8722;1) and aspartic acid higher than isoleucine (up to 0.83 mg g\&\#8722;1 DW\&\#8722;1). Levels of glutamine were higher (up to 25 mg g\&\#8722;1 DW\&\#8722;1) than glutamic acid (up to 20 mg g\&\#8722;1 DW\&\#8722;1). The course of the arginine content was higher in 2011/12 compared to 2012/13, 2013/14 and 2014/15 which showed only slight differences. The alanine content in the buds was denoted in the four seasons only by relatively minor changes. The histidine content was higher in 2011/12 and 2012/13 compared to 2013/14 and 2014/15 which showed a comparable pattern. For 6 amino acids (Asn, Asp, Ile, Glu, Arg, Ala), the highest content was observed in 2012/13, the warmest period between swollen bud and open cluster. However in 2014/15, the season with the lowest mean temperature of 8.8 °C, only the content of Gln was the lowest. It was not possible to explain any seasonal differences in the amino acid content by environmental factors (air temperature) on the basis of few seasons. From none of the measured free amino acids could a clear determination of the date of endodormancy release (t1) or the beginning of the ontogenetic development (t1*) be derived. Therefore, these amino acids are no suitable markers to improve phenological models for the beginning of cherry blossom.}, language = {en} } @article{BoeckerSchlierHolzHohmetal.2017, author = {Boecker-Schlier, Regina and Holz, Nathalie E. and Hohm, Erika and Zohsel, Katrin and Blomeyer, Dorothea and Buchmann, Arlette F. and Baumeister, Sarah and Wolf, Isabella and Esser, G{\"u}nter and Schmidt, Martin H. and Meyer-Lindenberg, Andreas and Banaschewski, Tobias and Brandeis, Daniel and Laucht, Manfred}, title = {Association between pubertal stage at first drink and neural reward processing in early adulthood}, series = {Addiction biology}, volume = {22}, journal = {Addiction biology}, publisher = {Wiley}, address = {Hoboken}, issn = {1355-6215}, doi = {10.1111/adb.12413}, pages = {1402 -- 1415}, year = {2017}, abstract = {Puberty is a critical time period during human development. It is characterized by high levels of risk-taking behavior, such as increased alcohol consumption, and is accompanied by various neurobiological changes. Recent studies in animals and humans have revealed that the pubertal stage at first drink (PSFD) significantly impacts drinking behavior in adulthood. Moreover, neuronal alterations of the dopaminergic reward system have been associated with alcohol abuse or addiction. This study aimed to clarify the impact of PSFD on neuronal characteristics of reward processing linked to alcohol-related problems. One hundred sixty-eight healthy young adults from a prospective study covering 25 years participated in a monetary incentive delay task measured with simultaneous EEG-fMRI. PSFD was determined according to the age at menarche or Tanner stage of pubertal development, respectively. Alcohol-related problems in early adulthood were assessed with the Alcohol Use Disorder Identification Test (AUDIT). During reward anticipation, decreased fMRI activation of the frontal cortex and increased preparatory EEG activity (contingent negative variation) occurred with pubertal compared to postpubertal first alcohol intake. Moreover, alcohol-related problems during early adulthood were increased in pubertal compared to postpubertal beginners, which was mediated by neuronal activation of the right medial frontal gyrus. At reward delivery, increased fMRI activation of the left caudate and higher feedback-related EEG negativity were detected in pubertal compared to postpubertal beginners. Together with animal findings, these results implicate PSFD as a potential modulator of psychopathology, involving altered reward anticipation. Both PSFD timing and reward processing might thus be potential targets for early prevention and intervention.}, language = {en} } @article{WittMeyerEbertetal.2017, author = {Witt, Barbara and Meyer, S{\"o}ren and Ebert, Franziska and Francesconi, Kevin A. and Schwerdtle, Tanja}, title = {Toxicity of two classes of arsenolipids and their water-soluble metabolites in human differentiated neurons}, series = {Archives of toxicology : official journal of EUROTOX}, volume = {91}, journal = {Archives of toxicology : official journal of EUROTOX}, publisher = {Springer}, address = {Heidelberg}, issn = {0340-5761}, doi = {10.1007/s00204-017-1933-x}, pages = {3121 -- 3134}, year = {2017}, abstract = {Arsenolipids are lipid-soluble organoarsenic compounds, mainly occurring in marine organisms, with arsenic-containing hydrocarbons (AsHCs) and arsenic-containing fatty acids (AsFAs) representing two major subgroups. Recently, toxicity studies of several arsenolipids showed a high cytotoxic potential of those arsenolipids in human liver and bladder cells. Furthermore, feeding studies with Drosophila melanogaster indicated an accumulation of arsenolipids in the fruit fly's brain. In this study, the neurotoxic potential of three AsHCs, two AsFAs and three metabolites (dimethylarsinic acid, thio/oxo-dimethylarsenopropanoic acid) was investigated in comparison to the toxic reference arsenite (iAsIII) in fully differentiated human brain cells (LUHMES cells). Thereby, in the case of AsHCs both the cell number and cell viability were reduced in a low micromolar concentration range comparable to iAsIII, while AsFAs and the applied metabolites were less toxic. Mechanistic studies revealed that AsHCs reduced the mitochondrial membrane potential, whereas neither iAsIII nor AsFAs had an impact. Furthermore, neurotoxic mechanisms were investigated by examining the neuronal network. Here, AsHCs massively disturbed the neuronal network and induced apoptotic effects, while iAsIII and AsFAs showed comparatively lesser effects. Taking into account the substantial in vitro neurotoxic potential of the AsHCs and the fact that they could transfer across the physiological barriers of the brain, a neurotoxic potential in vivo for the AsHCs cannot be excluded and needs to be urgently characterized.}, language = {en} } @article{EggersLovelaceKraft2017, author = {Eggers, Fabian and Lovelace, Kathi J. and Kraft, Frederik}, title = {Fostering creativity through critical thinking: The case of business start-up simulations}, series = {Creativity and innovation management}, volume = {26}, journal = {Creativity and innovation management}, publisher = {Wiley}, address = {Hoboken}, issn = {0963-1690}, doi = {10.1111/caim.12225}, pages = {266 -- 276}, year = {2017}, abstract = {Research suggests a positive link between critical thinking and creativity. However, this relationship has not been measured in an empirical study. This study aims to explore whether critical thinking can serve to enhance creativity and whether creativity positively mediates the relationship between critical thinking and business performance. In this study, we analyse these relationships within the entrepreneurial context of a web-based business start-up simulation. We examined data from 26 teams of three to four senior business students and found partial support for our hypotheses. Critical thinking positively influenced creativity, measured as the total number of unique product designs. Creativity (unique product designs) also positively mediated the link between critical thinking and performance. This effect, however, did not exist when creativity was assessed through advertisement designs. This research contributes to entrepreneurship and innovation management by demonstrating the importance of critical thinking as a basis for creativity and testing this relationship in a business start-up simulation context.}, language = {en} }