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Fewer invited talks by women in evolutionary biology symposia

Lower visibility of female scientists, compared to male scientists, is a potential reason for the under-representation of women among senior academic ranks. Visibility in the scientific community stems partly from presenting research as an invited speaker at organized meetings. We analysed the sex ratio of presenters at the European Society for Evolutionary Biology (ESEB) Congress 2011, where all

External Electric Field-Dependent Photoinduced Charge Transfer in a Donor-Acceptor System for an Organic Solar Cell

External electric field is incorporated into the generalized Mulliken-Hush model and Marcus theory. With this new development, we have investigated the field-dependent electronic structure and rate of photoinduced charge transfer in organic donor-acceptor dyad using time-dependent density functional theory and extensive multidimensional visualization techniques. The model is used to evaluate the i

Immune Indexes of Larks from Desert and Temperate Regions Show Weak Associations with Life History but Stronger Links to Environmental Variation in Microbial Abundance

Immune defense may vary as a result of trade-offs with other life-history traits or in parallel with variation in antigen levels in the environment. We studied lark species (Alaudidae) in the Arabian Desert and temperate Netherlands to test opposing predictions from these two hypotheses. Based on their slower pace of life, the trade-off hypothesis predicts relatively stronger immune defenses in de

To measure the impact of hearing protectors on the perception of speech in noise

Objective: To propose and evaluate a new method for assessing the potential impact on speech intelligibility when wearing a hearing protection device (HPD) in a noisy environment. Design: The method is based on a self adaptive method for finding the speech reception threshold (SRT) using speech material from the Callsign acquisition test (CAT) presented at a constant level while adjusting the leve

The executioners sing a new song: killer caspases activate microglia

Activation of microglia and inflammation-mediated neurotoxicity are suggested to have key roles in the pathogenesis of several neurodegenerative disorders. We recently published an article in Nature revealing an unexpected role for executioner caspases in the microglia activation process. We showed that caspases 8 and 3/7, commonly known to have executioner roles for apoptosis, can promote microgl

Quantum dot photodegradation due to CdSe-ZnO charge transfer: Transient absorption study

We study changes in ultrafast transient absorption due to photodegradation of quantum dots attached to ZnO nanowire. The time-resolved measurements reveal impact of photodegradation on three distinct kinetic components present in transient absorption tau similar to 7 ps, 80 ps, and 7.5 ns). In addition, we observe superlinear dependence of photodegradation rate on concentration of excited electron

Evidence for ligand hydrolysis and Fe(III) reduction in the dissolution of goethite by desferrioxamine-B

Desferrioxamine-B (DFOB) is a bacterial trihydroxamate siderophore and probably the most studied to date. However, the manner in which DFOB adsorbs at mineral surfaces and promotes dissolution is still under discussion. Here we investigated the adsorption and dissolution reactions in the goethite-DFOB system using both in situ infrared spectroscopic and quantitative analytical methods. Experiments

Elevated plasma levels of heparin-binding protein in intensive care unit patients with severe sepsis and septic shock

Introduction: Rapid detection of, and optimized treatment for, severe sepsis and septic shock is crucial for successful outcome. Heparin-binding protein (HBP), a potent inducer of increased vascular permeability, is a potentially useful biomarker for predicting outcome in patients with severe infections. Our aim was to study the systemic release and dynamics of HBP in the plasma of patients with s

Heat-induced aggregation of thylakoid membranes affect their interfacial properties.

Many of our most popular lipid containing foods are in emulsion form. These foods are often highly palatable with high caloric density, that subsequently increases the risk of overconsumption and possibly lead to obesity. Regulating the lipid bioavailability of high-fat foods is one approach to prevent overconsumption. Thylakoids, the chloroplast membrane, creates a barrier around lipid droplets,

Batch-Specific Discrimination Using Nuclear Quadrupole Resonance Spectroscopy

In this paper, we report on the identification of batches of analgesic paracetamol (acetaminophen) tablets using nitrogen-14 nuclear quadrupole resonance spectroscopy (N-14 NQR). The high sensitivity of NQR to the electron charge distribution surrounding the quadrupolar nucleus enables the unique characterization of the crystal structure of the material. Two hypothesis were tested on batches of th

Determination of Nicotine Absorption from Multiple Tobacco Products and Nicotine Gum

Snus is a smokeless tobacco product traditionally used in Scandinavia and available in pouched or loose forms. The objective of this study was to determine nicotine absorption for current pouched and loose snus products in comparison with a cigarette and an over-the-counter nicotine gum. We conducted an open-label, randomized, 6-way, crossover study involving 20 healthy snus and cigarette users. O

A Combinatorial Approach to $L_1$-Matrix Factorization

Recent work on low-rank matrix factorization has focused on the missing data problem and robustness to outliers and therefore the problem has often been studied under the $L_1$-norm. However, due to the non-convexity of the problem, most algorithms are sensitive to initialization and tend to get stuck in a local optimum. In this paper, we present a new theoretical framework aimed at achieving opt

The Geography and Structure of Global Innovation Networks: A Knowledge Base Perspective

This paper explores the geography and structure of global innovation networks (GINs) of two multinational companies belonging to industries with different knowledge bases. It contributes to the existing literature on knowledge bases, by studying both intra-firm and inter-firm GINs. By means of social network analysis based on primary data, we identify two different forms of GINs, namely the global

Plasma fetuin-A concentration, genetic variation in the AHSG gene and risk of colorectal cancer

Fetuin-A, also referred to as alpha 2-Heremans-Schmid glycoprotein (AHSG), is a liver protein known to inhibit insulin actions. Hyperinsulinemia is a possible risk factor for colorectal cancer; however, the role of fetuin-A in the development of colorectal cancer is unclear. We investigated the association between circulating fetuin-A and colorectal cancer risk in a nested case-control study withi

Small-angle X-ray Scattering Study of a Rex Family Repressor: Conformational Response to NADH and NAD(+) Binding in Solution.

The transcriptional repressor Rex is a sensor of the intracellular NADH/NAD(+) redox state through direct binding of NADH or NAD(+). Homodimeric Rex protein from Thermus aquaticus (T-Rex) and Bacillus subtilis (B-Rex) exists in several different conformations. In both organisms, Rex in complex with NADH has the DNA binding domains packed together at the dimer interface, whereas in the apo form of

Kinin-Stimulated B1 Receptor Signaling Depends on Receptor Endocytosis Whereas B2 Receptor Signaling Does Not.

Kinins are potent pro-inflammatory peptides that act through two G protein-coupled receptor subtypes, B1 (B1R) and B2 (B2R). Kinin-stimulated B2R signaling is often transient, whereas B1R signaling is sustained. This was confirmed by monitoring agonist-stimulated intracellular Ca(2+) mobilization in A10 smooth muscle cells expressing human wild-type B2R and B1R. We further studied the role of rece

TFPI cofactor function of protein S: essential role of the protein S SHBG-like domain

Protein S is a cofactor for tissue factor pathway inhibitor (TFPI), accelerating the inhibition of activated factor X (FXa). TFPI Kunitz domain 3 residue Glu226 is essential for enhancement of TFPI by protein S. To investigate the complementary functional interaction site on protein S, we screened 44 protein S point, composite or domain swap variants spanning the whole protein S molecule for their

Spontaneous activity and stretch-induced contractile differentiation are reduced in vascular smooth muscle of miR-143/145 knockout mice.

Stretch is essential for maintaining the contractile phenotype of vascular smooth muscle cells, and small non-coding microRNAs are known to be important in this process. Using a Dicer knockout model, we have previously reported that microRNAs are essential for stretch-induced differentiation and regulation of L-type calcium channel expression. The aim of this study was to investigate the importanc