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Spatial summation improves bird color vision in low light intensities

Color guides many important behaviors in birds. Previously we have shown that the intensity threshold for color discrimination in the chicken depends on the color contrast between stimuli and their brightness. The birds could discriminate larger color contrasts and brighter colors in lower light intensities. We suggested that chickens use spatial summation of cone signals to maintain color vision

Runge-Kutta Restarters for Multistep Methods in Presence of Frequent Discontinuities

Differential equations with discontinuities or differential equations coupled to discrete systems require frequent re-initializations of the numerical solution process. The classical starting process of multistep methods, based on increasing the order in the initialization phase, is computationally expensive when frequent discontinuities occur. Instead we propose to use the stage values or weight

The interplay of text, meaning and practice : Methodological considerations on discourse analysis in medical education

Context: The study of discourses (i.e. verbal interactions or written accounts) is increasingly used in social sciences to gain insight into issues connected to discourse, such as meanings, behaviours and actions. This paper situates discourse analysis in medical education, based on a framework developed in organisational discourse analysis and widely deployed in other social science disciplines.

Judging those closest from afar: The effect of psychological distance and abstraction on value-judgment correspondence in responses to ingroup moral transgressions

The purpose of the present research was to examine the effect of psychological distance and abstraction on judgment of ingroup moral transgressions. Based on Construal Level Theory (Trope & Liberman, 2010), we hypothesized that psychological distance and high level construal increases the degree to which moral value preference determines judgment (value-judgment correspondence) in response to

A multi-purpose imaging endstation for high-resolution micrometer-scaled sub-second tomography

Time-resolved imaging of dynamic processes, ranging from biological in vivo studies to materials under in situ and in operando conditions, requires a flexible endstation capable of controlling complex components that interact in different configurations and at high speeds. At the X02DA TOMCAT beamline we have recently achieved in situ tomographic measurements at a rate of 20 Hz. Independently, we

Anaerobes as sources of bioactive compounds and health promoting tools

Aerobic microorganisms have been sources of medicinal agents for several decades and an impressive variety of drugs have been isolated from their cultures, studied and formulated to treat or prevent diseases. On the other hand, anaerobes, which are believed to be the oldest life forms on earth and evolved remarkably diverse physiological functions, have largely been neglected as sources of bioacti

Isolation and cultivation of anaerobes

Anaerobic microorganisms play important roles in different biotechnological processes. Their complex metabolism and special cultivation requirements have led to less isolated representatives in comparison to their aerobic counterparts. In view of that, the isolation and cultivation of anaerobic microorganisms is still a promising venture, and conventional methodologies as well as considerations an

The Role of Mitochondria, Oxidative Stress, and the Radical-binding Protein A1M in Cultured Porcine Retina.

PURPOSE:The purpose of this study was to explore the relationship between oxidative stress, antioxidant defense, mitochondrial structure, and biomechanical tissue support in the isolated porcine retina.METHODS:Full-thickness retinal sheets were isolated from adult porcine eyes. Retinas were cultured for 2 or 48 h using (1) a previously established low-support explant protocol with photoreceptors pPurpose: The purpose of this study was to explore the relationship between oxidative stress, antioxidant defense, mitochondrial structure, and biomechanical tissue support in the isolated porcine retina.Methods: Full-thickness retinal sheets were isolated from adult porcine eyes. Retinas were cultured for 2 or 48 h using (1) a previously established low-support explant protocol with photoreceptors

Ten genes and two topologies : An exploration of higher relationships in skipper butterflies (Hesperiidae)

Despite multiple attempts to infer the higher-level phylogenetic relationships of skipper butterflies (Family Hesperiidae), uncertainties in the deep clade relationships persist. The most recent phylogenetic analysis included fewer than 30% of known genera and data from three gene markers. Here we reconstruct the higher-level relationships with a rich sampling of ten nuclear and mitochondrial mark

Prognostic impact of epigenetic classification in chronic lymphocytic leukemia : The case of subset #2

ABSTRACT: Based on the methylation status of 5 single CpG sites, a novel epigenetic classification of chronic lymphocytic leukemia (CLL) was recently proposed, classifying CLL patients into 3 clinico-biological subgroups with different outcome, termed memory like CLL (m-CLL), naïve like CLL (n-CLL), and a third intermediate CLL subgroup (i-CLL). While m-CLL and n-CLL patients at large corresponded

Novel metabolites from the roots of Cadaba natalensis

From an extract of the roots of Cadaba natalensis Sond. the novel macrocyclic dibenzo-diazacyclododecanedione 1 was isolated together with (S)-2-ethyl-2-methyloxazolidin-5-one (2a). In addition, the five known compounds were obtained. Of these, (R)-5-ethyl-5-methyloxazolidin-2-one (3) is reported as a natural product for the first time. The structures of the isolated compounds were elucidated by a

A simple method to calculate first-passage time densities with arbitrary initial conditions

Numerous applications all the way from biology and physics to economics depend on the density of first crossings over a boundary. Motivated by the lack of general purpose analytical tools for computing first-passage time densities (FPTDs) for complex problems, we propose a new simple method based on the independent interval approximation (IIA). We generalise previous formulations of the IIA to inc

Galactomannan catabolism conferred by a polysaccharide utilisation locus of Bacteroides ovatus : enzyme synergy and crystal structure of a β-mannanase

A recently identified polysaccharide utilisation locus (PUL) from Bacteroides ovatus ATCC8483 is transcriptionally upregulated during growth on galacto- and glucomannans. It encodes two putative glycoside hydrolase family 26 (GH26) β-mannanases, BoMan26A and BoMan26B, and a GH36 α-galactosidase, BoGal36A. The PUL also includes two glycan binding proteins, confirmed by β-mannan affinity electrophorA recently identified polysaccharide utilization locus (PUL) from Bacteroides ovatus ATCC 8483 is transcriptionally up-regulated during growth on galacto- and glucomannans. It encodes two glycoside hydrolase family 26 (GH26) β-mannanases, BoMan26A and BoMan26B, and a GH36 α-galactosidase, BoGal36A. The PUL also includes two glycan-binding proteins, confirmed by β-mannan affinity electrophoresis. W

Scale-up of high-solid enzymatic hydrolysis of steam-pretreated softwood : the effects of reactor flow conditions

The importance of flow conditions during scale-up of high-solid enzymatic hydrolysis of steam-pretreated spruce was demonstrated by comparing hydrolysis rates between laboratory (2 L) and demonstration (4 m3) scale. A positive effect of increased agitation speed on the rate of enzymatic hydrolysis was found regardless of scale. Importantly, the hydrolysis rate was higher at the larger scale when c

Regulation of human cell viability by the host defence peptide LL-37

Accumulating evidence suggests that the main human cathelicidin peptide, LL-37, may influence host cell viability and pro-inflammatory signaling when locally overexpressed. LL-37 has pro-inflammatory properties linked to the development of for example psoriasis, rosacea, SLE and atherosclerosis. However, the importance of LL-37-induced host cell permeabilization and cytotoxic effects are poorly un

Linking intra- and interspecific assortative mating : Consequences for asymmetric sexual isolation

Assortative mating is of interest because of its role in speciation and the maintenance of species boundaries. However, we know little about how within-species assortment is related to interspecific sexual isolation. Most previous studies of assortative mating have focused on a single trait in males and females, rather than utilizing multivariate trait information. Here, we investigate how intrasp

Generic technique to grow III-V semiconductor nanowires in a closed glass vessel

Crystalline III-V semiconductor nanowires have great potential in fabrication of nanodevices for applications in nanoelectronics and optoelectronics, and for studies of novel physical phenomena. Sophisticated epitaxy techniques with precisely controlled growth conditions are often used to prepare high quality III-V nanowires. The growth process and cost of these experiments are therefore dedicated