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The German Enlightenment
(2017)
The term Enlightenment (or Aufklärung) remains heavily contested. Even when historians delimit the remit of the concept, assigning it to a particular historical period rather than to an intellectual or moral programme, the public resonance of the Enlightenment remains high and problematic—especially when equated in an essentialist manner with modernity or some core values of ‘the West’. This Forum has been convened to discuss recent research on the Enlightenment in Germany, different views of the term and its ideological use in public discourse outside academia (and sometimes within it).
Price shock transmission
(2017)
This study assesses the degree of vertical price transmission along the wheat-bread value chain in Ethiopia. This is pursued by applying a vector error correction model and an impulse response analysis using monthly price data for the period 2000-2015. Our analysis considers transmission of price shocks across different market levels, including from the international and domestic wheat grain markets at the upstream to the domestic wheat bread market at the downstream of the value chain. The empirical findings indicate that significant cointegration exists across prices of the different market stages. There is a transmission from international prices to domestic prices at downstream markets, in particular to flour and bread prices. Prices at upstream markets are largely influenced by the domestic wholesale market. In general, the speed of adjustment is quite slow with a half-life of about one year for restoring the equilibrium price relationship. As price margins between the different market stages in the value chain have substantially decreased in the last 15 years, higher transmission, and thus exposure to international market shocks, can be expected in the future. The results also show that causal relationships exist between prices at different market stageswith the wholesale market identified as the key market level where prices and price expectations are formed.
The effects of biodiversity on ecosystem functioning generally increase over time, but the underlying processes remain unclear. Using 26 long-term grassland and forest experimental ecosystems, we demonstrate that biodiversity-ecosystem functioning relationships strengthen mainly by greater increases in functioning in high-diversity communities in grasslands and forests. In grasslands, biodiversity effects also strengthen due to decreases in functioning in low-diversity communities. Contrasting trends across grasslands are associated with differences in soil characteristics.
Durkheim in Germany
(2017)
Dialogue. Divergence. Veiled Reception. Criticism: Georg Simmel’s
relationship with Emile Durkheim
(2017)
Simmel was the only German sociologist who directly cooperated with Durkheim. After an initial impression of convergence between the sociology of social facts and the sociology of social forms, a break between the two founders of sociology became inevitable. Yet, Durkheim and Simmel went on positioning themselves against one other in the years ahead. Durkheim’s allegation of ‘individual psychologism’ induced Simmel to a veiled reception of Durkheim’s methodological approach that permitted him to refine the sociological epistemology he eventually presented in the Soziologie published in 1908. On this basis, he was able to formulate a final criticism of the sociology of social facts as a social psychology.
The interview offers a reconstruction of the German reception of Durkheim since the middle of the 1970s. Hans Joas, who was one of its major protagonists, discusses the backdrop that finally permitted a scholarly examination of Durkheim’s sociology in Germany. Focussing on his personal reception Joas then gives an account of the Durkheimian themes that inspire his work.
Just after the publication of the Theory of Communicative Action in 1981, a new generation of interpreters started a different reception of Durkheim in Germany. Hans-Peter Müller, sociologist and editor of the German translation of Leçons de sociologie, reconstructs the history of the German Durkheim’s Reception and illuminates the reasons for his interest in the French sociologist. He delivers different insights into the background which permitted the post-Habermasian generation to reach a new understanding of Durkheim’s work by enlightening the scientific and political conditions from which this new sensibility emerged.
Aims: The MARLINA-T2D study (ClinicalTrials. gov, NCT01792518) was designed to investigate the glycaemic and renal effects of linagliptin added to standard-of-care in individuals with type 2 diabetes and albuminuria. Methods: A total of 360 individuals with type 2 diabetes, HbA1c 6.5% to 10.0% (48-86 mmol/ mol), estimated glomerular filtration rate (eGFR) >= 30 mL/min/1.73 m(2) and urinary albumin-tocreatinine ratio (UACR) 30-3000 mg/g despite single agent renin-angiotensin-system blockade were randomized to double-blind linagliptin (n = 182) or placebo (n = 178) for 24 weeks. The primary and key secondary endpoints were change from baseline in HbA1c at week 24 and time-weighted average of percentage change from baseline in UACR over 24 weeks, respectively. Results: Baseline mean HbA1c and geometric mean (gMean) UACR were 7.8% +/- 0.9% (62.2 +/- 9.6 mmol/mol) and 126 mg/g, respectively; 73.7% and 20.3% of participants had microalbuminuria or macroalbuminuria, respectively. After 24 weeks, the placebo-adjusted mean change in HbA1c from baseline was -0.60% (-6.6 mmol/mol) (95% confidence interval [CI], -0.78 to -0.43 [-8.5 to -4.7 mmol/mol]; P <.0001). The placebo-adjusted gMean for time-weighted average of percentage change in UACR from baseline was -6.0% (95% CI, -15.0 to 3.0; P =.1954). The adverse-event profile, including renal safety and change in eGFR, was similar between the linagliptin and placebo groups. Conclusions: In individuals at early stages of diabetic kidney disease, linagliptin significantly improved glycaemic control but did not significantly lower albuminuria. There was no significant change in placebo-adjusted eGFR. Detection of clinically relevant renal effects of linagliptin may require longer treatment, as its main experimental effects in animal studies have been to reduce interstitial fibrosis rather than alter glomerular haemodynamics.
River restoration is a main emphasis of river management in European countries. Cross-national comparisons of its implementation are still rare in scientific literature. Based on French and German national censuses, this study compares river restoration practices and monitoring by analysing 102 French and 270 German projects. This comparison aims to draw a spatial and temporal framework of restoration practices in both countries to identify potential drivers of cross-national similarities and differences. The results underline four major trends: (1) a lag of almost 15 years in river restoration implementation between France and Germany, with a consequently higher share of projects in Germany than in France, (2) substantial similarities in restored reach characteristics, short reach length, small rivers, and in "agricultural" areas, (3) good correspondences between stressors identified and restoration measures implemented. Morphological alterations were the most important highlighted stressors. River morphology enhancement, especially instream enhancements, were the most frequently implemented restoration measures. Some differences exist in specific restoration practices, as river continuity restoration were most frequently implemented in French projects, while large wood introduction or channel re-braiding were most frequently implemented in German projects, and (4) some quantitative and qualitative differences in monitoring practices and a significant lack of project monitoring, especially in Germany compared to France. These similarities and differences between Germany and France in restoration application and monitoring possibly result from a complex set of drivers that might be difficult to untangle (e.g., environmental, technical, political, cultural).
Prólogo
(2017)
Vorwort
(2017)
Patient involvement (PI) in research is increasingly required as a means to improve relevance and meaningfulness of research results. PI has been widely promoted by the National Institute for Health Research in England in the last years. In Germany, widespread involvement of patients in research is still missing. The methods used to realize PI have been developed mainly in English research contexts, and detailed information on how to involve patients in systematic reviews is rare. Therefore, the aim of the study was that patients contribute and prioritize clinically relevant outcomes to a systematic review on meta-cognitive interventions, and to evaluate a patient workshop as well as patients’ perceptions of research involvement. Seven patients with experience in psychiatric care participated in our workshop. They focused on outcomes pre-defined in the review protocol (e.g., meta-cognitive or cognitive changes, symptomatology, quality of life), neglected other outcomes (like satisfaction with treatment, acceptability), and added relevant new ones (e.g., scope of action/autonomy, applicability). Altogether, they valued the explicit workshop participation positively. However, some suggested to involve patients at an earlier stage and to adapt the amount of information given. Further systematic reviews would benefit from the involvement of patients in the definition of other components of the review question (like patients or interventions), in the interpretation of key findings or in drafting a lay summary.
Проведен анализ пространственной семантики различных категорий русских существительных, входящих в психолингви-стическую базуданных; особое внимание уделяется абстрактным концептам. Выявлены различия пространственной семантики наименований физических ощущений и действий, эмоций, ментальных процессов. Полученны ерезультаты обсуждаются с точки зрения отдельных подходов в рамках теории воплощенного познания – теории концептуальной метафоры, теории слов как социальных инструментов (WAT, Words As social Tools), нейросемантики.
Epigenetic maintenance of gene repression is essential for development. Polycomb complexes are central to this memory, but many aspects of the underlying mechanism remain unclear. LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) binds Polycomb-deposited H3K27me3 and is required for repression of many Polycomb target genes in Arabidopsis. Here we show that LHP1 binds RNA in vitro through the intrinsically disordered hinge region. By independently perturbing the RNA-binding hinge region and H3K27me3 (trimethylation of histone H3 at Lys27) recognition, we found that both facilitate LHP1 localization and H3K27me3 maintenance. Disruption of the RNAbinding hinge region also prevented formation of subnuclear foci, structures potentially important for epigenetic repression.
For n∈N , let Xn={a1,a2,…,an} be an n-element set and let F=(Xn;<f) be a fence, also called a zigzag poset. As usual, we denote by In the symmetric inverse semigroup on Xn. We say that a transformation α∈In is fence-preserving if x<fy implies that xα<fyα, for all x,y in the domain of α. In this paper, we study the semigroup PFIn of all partial fence-preserving injections of Xn and its subsemigroup IFn={α∈PFIn:α−1∈PFIn}. Clearly, IFn is an inverse semigroup and contains all regular elements of PFIn. We characterize the Green’s relations for the semigroup IFn. Further, we prove that the semigroup IFn is generated by its elements with rank ≥n−2. Moreover, for n∈2N, we find the least generating set and calculate the rank of IFn.
New data from the LEADER trial show that the glucagon-like peptide 1 receptor agonist liraglutide protects against diabetic nephropathy in patients with type 2 diabetes mellitus. The renoprotective efficacy of liraglutide is not, however, as great as that reported for the sodium-glucose cotransporter 2 inhibitor emplagiflozin in the EMPA-REG OUTCOME trial.
Disentangling shallow‐water bulk carbonate carbon isotope archives into primary and diagenetic components is a notoriously difficult task and even diagenetically screened records often provide chemostratigraphic patterns that significantly differ from global signals. This is mainly caused by the polygenetic nature of shallow‐water carbonate substrates, local carbon cycle processes causing considerable neritic–pelagic isotope gradients and the presence of hiatal surfaces resulting in extremely low carbonate preservation rates. Provided here is an in‐depth petrographic and geochemical evaluation of different carbonate phases of a mid‐Cretaceous (Barremian–Aptian) shallow‐water limestone succession (Jabal Madar section) deposited on the tropical Arabian carbonate platform in Oman. The superposition of stable isotope signatures of identified carbonate phases causes a complex and often noisy bulk carbon isotope pattern. Blocky sparite cements filling intergranular pores and bioclastic voids evidence intermediate to (arguably) deep burial diagenetic conditions during their formation, owing to different timing or differential faulting promoting the circulation of fluids from variable sources. In contrast, sparite cements filling sub‐vertical veins reveal a rock‐buffered diagenetic fluid composition with an intriguing moderate enrichment in 13C, probably due to fractionation during pressure release in the context of the Miocene exhumation of the carbonate platform under study. The presence of abundant, replacive dedolomite in mud‐supported limestone samples forced negative carbon and oxygen isotope changes that are either associated with the thermal breakdown of organic matter in the deep burial realm or the expulsion of buried meteoric water in the intermediate burial realm. Notwithstanding the documented stratigraphically variable and often facies‐related impact of different diagenetic fluids on the bulk‐rock stable isotope signature, the identification of diagenetic end‐members defined δ13C and δ18O threshold values that allowed the most reliable ‘primary’ bulk carbon isotope signatures to be extracted. Most importantly, this approach exemplifies how to place regional shallow‐water stable isotope patterns with evidence for a complex multi‐stage diagenetic history into a supraregional or even global context.
How cells establish and maintain a well-defined size is a fundamental question of cell biology. Here we investigated to what extent the microtubule cytoskeleton can set a predefined cell size, independent of an enclosing cell membrane. We used electropulse-induced cell fusion to form giant multinuclear cells of the social amoeba Dictyostelium discoideum. Based on dual-color confocal imaging of cells that expressed fluorescent markers for the cell nucleus and the microtubules, we determined the subcellular distributions of nuclei and centrosomes in the giant cells. Our two- and three-dimensional imaging results showed that the positions of nuclei in giant cells do not fall onto a regular lattice. However, a comparison with model predictions for random positioning showed that the subcellular arrangement of nuclei maintains a low but still detectable degree of ordering. This can be explained by the steric requirements of the microtubule cytoskeleton, as confirmed by the effect of a microtubule degrading drug.
We argue that coherence relations (relations between propositions, such as Concession or Purpose) are signalled more frequently and by more means than is generally believed. We examine how coherence relations in text are indicated by all possible textual signals, and whether every relation is signalled. To that end, we conducted a corpus study on the RST Discourse Treebank, a corpus of newspaper articles annotated for rhetorical (or coherence) relations. Results from our corpus study show that most relations in text (over 90%) are signalled and also that most signalled relations (over 80%) are indicated not only by discourse markers (and, but, if, since), but also by a wide variety of signals other than discourse markers, such as reference, lexical, semantic, syntactic and graphical features. These findings suggest that signalling of coherence relations is much more sophisticated than previously thought.
This study combines spaceborne multitemporal and hyperspectral data to analyze the spatial distribution of surface evaporite minerals and changes in a semi-arid depositional environment associated with episodic flooding events, the Omongwa salt pan (Kalahari, Namibia). The dynamic of the surface crust is evaluated by a change-detection approach using the Iterative-reweighted Multivariate Alteration Detection (IR-MAD) based on the Landsat archive imagery from 1984 to 2015. The results show that the salt pan is a highly dynamic and heterogeneous landform. A change gradient is observed from very stable pan border to a highly dynamic central pan. On the basis of hyperspectral EO-1 Hyperion images, the current distribution of surface evaporite minerals is characterized using Spectral Mixture Analysis (SMA). Assessment of field and image endmembers revealed that the pan surface can be categorized into three major crust types based on diagnostic absorption features and mineralogical ground truth data. The mineralogical crust types are related to different zones of surface change as well as pan morphology that influences brine flow during the pan inundation and desiccation cycles. These combined information are used to spatially map depositional environments where the more dynamic halite crust concentrates in lower areas although stable gypsum and calcite/sepiolite crusts appear in higher elevated areas.
Effektive Lernzeitnutzung gilt als einer der wichtigsten Prädiktoren für erfolgreichen Unterricht. Die vorliegende Studie untersucht in einem dyadischen kooperativen Lernsetting, wie sich die kognitiven Grundfähigkeiten und Zielorientierungen der Partner in den offenen Phasen eines Planspielunterrichts auf die effektive Lernzeitnutzung auswirken. Hierzu nutzten wir die neu entwickelte Multimodale Video- und Audioanalysemethode (MuVA), welche es ermöglicht, Schüler-Interaktionen in offenen Unterrichtsphasen reliabel zu dokumentieren. In zweischrittigen Regressionsmodellen ließ sich aufzeigen, dass sowohl Lernenden- als auch Partnervariablen signifikante Anteile der Varianz erklären: Bei Lernenden selbst beeinflusst eine hohe Leistungszielorientierung die effektive Lernzeitnutzung negativ und eine hohe Vermeidungs-Leistungszielorientierung positiv. Einflüsse durch die Eigenschaften der Lernpartner zeigten sich in positiver Richtung für hohe Ausprägungen der Lern-Zielorientierung und der Vermeidungs-Leistungszielorientierung sowie in negativer Richtung für eine hohe Arbeitsvermeidungsorientierung. Kognitive Grundfähigkeiten hatten keinen Einfluss auf die effektive Lernzeitnutzung.
The performance of organic photovoltaic blend devices is critically dependent on the polymer:fullerene interface. These interfaces are expected to impact the structural and thermal properties of the polymer with regards to the conjugated backbone planarity and transition temperatures during annealing/cooling processes. Here, we report the impact of fullerene intercalation on structural and thermal properties of poly(2,5-bis(3-tetradecylthiophen-2-yOthieno[3,2-b]thiophene (PBTTT), a highly stable material known to exhibit liquid crystalline behavior. We undertake a detailed systematic study of the extent of intercalation in the PBTTT:fullerene blend, considering the use of four different fullerene derivatives and also varying the loading ratios. Resonant Raman spectroscopy allows morphology in situ during controlled heating and cooling. We find that small fullerene molecules readily intercalate into PBTTT crystallites, resulting in a planarization of the polymer backbone, but high fullerene loading ratios or larger fullerenes result in nonintercalated domains. During cooling from melt, nonintercalated blend films are found to return to their original morphology and reproduce all thermal transitions on cooling with minimal hysteresis. Intercalated blend films show significant hysteresis on cooling due to the crystallized fullerene attempting to reintercalate. The strongest hysteresis is for intercalated blend films with excess fullerene loading ratio, which form a distinct nanoribbon morphology and exhibit a reduced geminate recombination rate. These results reveal that careful consideration should be taken during device fabrication, as postdeposition thermal treatments significantly impact the charge generation and recombination dynamics.
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.
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.
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.
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.
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.
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.
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.
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.
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‐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‐adaptation. Phenotypic and behavioral comparisons suggest that neither life‐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‐free, aphid host. In concurrence with the specificity of each parasitoid lineages’ infectivity, most differentially expressed parasitoid transcripts were also lineage‐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.
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.
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.
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.
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.
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.
F2 slope as a Perceptual Cue for the Front-Back Contrast in Standard Southern British English
(2017)
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].
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.
Towards identifying dyslexia in Standard Indonesian: the development of a reading assessment battery
(2017)
Psychometric evaluation of the German version of the Intuitive Eating Scale-2 in a community sample
(2017)
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.
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.
Synthesis of Pyridylanthracenes and Their Reversible Reaction with Singlet Oxygen to Endoperoxides
(2017)
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.
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.
Editorial
(2017)
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.