Wind Farm Facilities in Germany Kill Noctule Bats from Near and Far

Over recent years, it became widely accepted that alternative, renewable energy may come at some risk for wildlife, for example, when wind turbines cause large numbers of bat fatalities. To better assess likely populations effects of wind turbine related wildlife fatalities, we studied the geographical origin of the most common bat species found dead below German wind turbines, the noctule bat (Nyctalus noctula). We measured stable isotope ratios of non-exchangeable hydrogen in fur keratin to separate migrants from local individuals, used a linear mixed-effects model to identify temporal, spatial and biological factors explaining the variance in measured stable isotope ratios and determined the geographical breeding provenance of killed migrants using isoscape origin models. We found that 72% of noctule bat casualties (n = 136) were of local origin, while 28% were long-distance migrants. These findings highlight that bat fatalities at German wind turbines may affect both local and distant populations. Our results indicated a sex and age-specific vulnerability of bats towards lethal accidents at turbines, i.e. a relatively high proportion of killed females were recorded among migratory individuals, whereas more juveniles than adults were recorded among killed bats of local origin. Migratory noctule bats were found to originate from distant populations in the Northeastern parts of Europe. The large catchment areas of German wind turbines and high vulnerability of female and juvenile noctule bats call for immediate action to reduce the negative cross-boundary effects of bat fatalities at wind turbines on local and distant populations. Further, our study highlights the importance of implementing effective mitigation measures and developing species and scale-specific conservation approaches on both national and international levels to protect source populations of bats. The efficacy of local compensatory measures appears doubtful, at least for migrant noctule bats, considering the large geographical catchment areas of German wind turbines for this species.     

Construction of an annotated corpus to support biomedical information extraction

Background  

Information Extraction (IE) is a component of text mining that facilitates knowledge discovery by automatically locating instances of interesting biomedical events from huge document collections. As events are usually centred on verbs and nominalised verbs, understanding the syntactic and semantic behaviour of these words is highly important. Corpora annotated with information concerning this behaviour can constitute a valuable resource in the training of IE components and resources.     

Directed evolution reveals the mechanism of HitRS signaling transduction in Bacillus anthracis

Two component systems (TCSs) are a primary mechanism of signal sensing and response in bacteria. Systematic characterization of an entire TCS could provide a mechanistic understanding of these important signal transduction systems. Here, genetic selections were employed to dissect the molecular basis of signal transduction by the HitRS system that detects cell envelope stress in the pathogen Bacillus anthracis. Numerous point mutations were isolated within HitRS, 17 of which were in a 50-residue HAMP domain. Mutational analysis revealed the importance of hydrophobic interactions within the HAMP domain and highlighted its essentiality in TCS signaling. In addition, these data defined residues critical for activities intrinsic to HitRS, uncovered specific interactions among individual domains and between the two signaling proteins, and revealed that phosphotransfer is the rate-limiting step for signal transduction. Furthermore, this study establishes the use of unbiased genetic selections to study TCS signaling and provides a comprehensive mechanistic understanding of an entire TCS.     

In Vivo Evidence for Serine Biosynthesis-Defined Sensitivity of Lung Metastasis,but Not of Primary Breast Tumors,to mTORC1 Inhibition

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The Causal Effect of Market Priming on Trust: An Experimental Investigation Using Randomized Control

We report data from laboratory experiments where participants were primed using phrases related to markets and trade. Participants then participated in trust games with anonymous strangers. The decisions of primed participants are compared to those of a control group. We find evidence that priming for market participation affects positively the beliefs regarding the trustworthiness of anonymous strangers and increases trusting decisions.     

A Novel Three-dimensional Flow Chamber Device to Study Chemokine-directed Extravasation of Cells Circulating under Physiological Flow Conditions

Extravasation of circulating cells from the bloodstream plays a central role in many physiological and pathophysiological processes, including stem cell homing and tumor metastasis. The three-dimensional flow chamber device (hereafter the 3D device) is a novel in vitro technology that recreates physiological shear stress and allows each step of the cell extravasation cascade to be quantified. The 3D device consists of an upper compartment in which the cells of interest circulate under shear stress, and a lower compartment of static wells that contain the chemoattractants of interest. The two compartments are separated by porous inserts coated with a monolayer of endothelial cells (EC). An optional second insert with microenvironmental cells of interest can be placed immediately beneath the EC layer. A gas exchange unit allows the optimal CO₂ tension to be maintained and provides an access point to add or withdraw cells or compounds during the experiment. The test cells circulate in the upper compartment at the desired shear stress (flow rate) controlled by a peristaltic pump. At the end of the experiment, the circulating and migrated cells are collected for further analyses. The 3D device can be used to examine cell rolling on and adhesion to EC under shear stress, transmigration in response to chemokine gradients, resistance to shear stress, cluster formation, and cell survival. In addition, the optional second insert allows the effects of crosstalk between EC and microenvironmental cells to be examined. The translational applications of the 3D device include testing of drug candidates that target cell migration and predicting the in vivo behavior of cells after intravenous injection. Thus, the novel 3D device is a versatile and inexpensive tool to study the molecular mechanisms that mediate cellular extravasation.     

Isolation and characterization of a 22 kDa protein with antifungal properties from maize seeds.

We have purified a 22 kDa protein from maize seeds to homogeneity by ammonium sulfate precipitation, chitin extraction and Mono-S column chromatography. The purified protein inhibited the growth of the agronomically important pathogens of potato wilt (Fusarium oxysporum) and tomato early blight (Alternaria solani). Sequence analysis of the purified protein showed that it has 52% homology with the sweet protein thaumatin (Edens, L., Hselinga, L., Klok, R., Ledeboer, A. M., Maat, J., Toonen, M. Y., Visser, C., and Verrips, C. (1982) Gene 18, 1-12), 57% homology with the pathogenesis-related protein (Cornelissen, B. J. C., Huijsduijnen, R. A. M., and Bol, J. F. (1986) Nature 321, 531-532) and 99% homology with the 22 kDa trypsin/alpha-amylase inhibitor (Richardson, M., Valdes-Rodriguez, S., and Blanco-Labra, A. (1987) Nature 327, 432-434).     

Crystal structure and functional characterization of selenocysteine-containing glutathione peroxidase 4 suggests an alternative mechanism of peroxide reduction

Glutathione peroxidases (GPX) are anti-oxidative enzymes that reduce organic and inorganic hydroperoxides to the corresponding alcohols at the expense of reduced glutathione. The human genome involves eight GPX genes and five of them encode for selenocysteine-containing enzymes. Among the human GPX-isoforms, GPX4 is unique since it is capable of reducing complex hydroperoxy ester lipids such as hydroperoxy phospholipids and hydroperoxy cholesterolesters. Using a number of genetically modified mouse strains the biological role of GPX4 has comprehensively characterized but the molecular enzymology is less well explored. This lack of knowledge is partly related to the fact that mammalian selenoproteins are not high-level expressed in conventional overexpression systems. To explore the structural and functional properties of human GPX4 we expressed this selenoprotein in a cysteine-auxotrophic E. coli strain using a semi-chemical expression strategy. The recombinant enzyme was purified in mg amounts from the bacterial lysate to electrophoretic homogeneity and characterized with respect to its protein-chemical and enzymatic properties. Its crystal structure was solved at 1.3?Å resolution and the X-ray data indicated a monomeric protein, which contains the catalytic selenium at the redox level of the seleninic acid. These data suggest an alternative reaction mechanism involving three different redox states (selenol, selenenic acid, seleninic acid) of the catalytically active selenocysteine.