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Protochlorophyllide a: A Comprehensive Photophysical Picture
The photochemistry of protochlorophyllide a, a precursor in the biosynthesis of chlorophyll and substrate of the light regulated enzyme protochlorophyllide oxidoreductase, is investigated by pump-probe spectroscopy. Upon excitation into the lowest lying Q-band the light induced changes ore recorded over a wide range of probe wavelengths in the visible and near-IR region between 500 and 1000 nm. Fo
Characterization of a proton pumping transmembrane protein incorporated into a supported three-dimensional matrix of proteoliposomes
Surface analytical tools have gained interest in the bioanalytical field during recent years because they offer the possibility of more detailed investigations of biomolecular interactions. To be able to use such tools, the biomolecules of interest must be immobilized to a surface in a functioning way. For small water-soluble biomolecules, the surface immobilization is quite straightforward, but i
Interaction of fusidic acid with lipid membranes: Implications to the mechanism of antibiotic activity
We have studied the effects of cholesterol and steroid-based antibiotic fusidic acid (FA) on the behavior of lipid bilayers using a variety of experimental techniques together with atomic-scale molecular dynamics simulations. Capillary electrophoretic measurements showed that FA was incorporated into fluid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine membranes. Differential scanning calorimetr
The Large-billed Reed Warbler Acrocephalus orinus revisited
The Large-billed Reed Warbler Acrocephalus orinus is known only from the type specimen, collected in Himachal Pradesh, India, in 1867. The specimen is poorly prepared, and it has been suggested that it could represent an isolated form of the Clamorous Reed Warbler A. stentoreus or an aberrant Blyth's Reed Warbler A. dumetorum. We tested the affinity of A. orinus by (1) re-examining the morphology
Hippocampal GABA(A) channel conductance increased by diazepam
Benzodiazepines, which are widely used clinically for relief of anxiety and for sedation, are thought to enhance synaptic inhibition in the central nervous system by increasing the open probability of chloride channels activated by the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). Here we show that the benzodiazepine diazepam can also increase the conductance of GABAA channels activa
Effective software project management education through simulation models: an externally replicated experiment
It is an undeniable fact that software project managers need reliable techniques and robust tool support to be able to exercise a fine control over the development process so that products can be delivered in time and within budget. Therefore, managers need to be trained so that they could learn and use new techniques and be aware of their possible impacts. In this context, effective learning is a
Fine-needle aspiration cytology of soft tissue lesions: Diagnostic challenges
Clinical and radiographic data provide important information in the evaluation of soft tissue lesions/neoplasms. Morphologic tissue and cytologic examination is considered to be a necessary part of the diagnostic work-up. The standard procedure for obtaining tumor tissue for morphologic evaluation has been incisional (open) or core needle biopsy. An increasing use of minimally invasive diagnostic
Mutant huntingtin interacts with {beta}-tubulin and disrupts vesicular transport and insulin secretion.
Huntington's disease is a severe progressive neurodegenerative disorder caused by a CAG-expansion in the IT15 gene, which encodes huntingtin. The disease primarily affects the neostriatum and cerebral cortex and also associates with increased incidence of diabetes. Here, we show that mutant huntingtin disrupts intracellular transport and insulin secretion by direct interference with microtubular b
Inter- and intralocus recombination drive MHC class IIB gene diversification in a teleost, the three-spined stickleback Gasterosteus aculeatus
The mutational mechanism underlying the striking diversity in MHC (major histocompatibility complex) genes in vertebrates is still controversial. In order to evaluate the role of inter- and intragenic recombination in MHC gene diversification, we examined patterns of nucleotide polymorphism across an exon/intron boundary in a sample of 31 MHC class IIB sequences of three-spined stickleback (Gaster
Environmental enrichment alters nerve growth factor-induced gene A and glucocorticoid receptor messenger RNA expression after middle cerebral artery occlusion in rats
Housing rats in an enriched environment after focal brain ischemia improves functional outcome without changes in infarct volume, suggesting neuroplastic changes outside the lesion. In this study, permanent occlusion of the middle cerebral artery was followed by housing in an enriched or a standard environment. Nerve growth factor-induced gene A and glucocorticoid receptor messenger RNA expression
Two-step steam pretreatment of softwood with SO2 impregnation for ethanol production
Two-step steam pretreatment of softwood was investigated with the aim of improving the enzymatic digestibility for ethanol production. In the first step, softwood was impregnated with SO2 and steam pretreated at different severities. The first step was performed at low severity to hydrolyze the hemicellulose and release the sugars into the solution. The combination of time and temperature that yie
Structure and functional properties of the Bacillus subtilis transcriptional repressor Rex.
The transcription factor Rex has been implicated in regulation of the expression of genes important for fermentative growth and for growth under conditions of low oxygen tension in several Gram-positive bacteria. Rex senses the redox poise of the cell through changes in the NADH/NAD(+) ratio. The crystal structures of two essentially identical Rex proteins, from Thermus aquaticus and T. thermophil
Skeletal muscle telomere length is not impaired in healthy physically active old women and men
We have previously shown that the number of satellite cells is lower in old than young men and women. The aim of this study was to further explore the effects of aging on the regenerative potential of skeletal muscle in 16 young and 26 old men and women with comparable physical activity level (young, 25 +/- 4 years; old, 75 +/- 4 years). Mean and minimum telomere lengths were determined using Sout
Application of advanced laser diagnostics for the investigation of the ionization sensor signal in a combustion bomb
The ionization sensor is an electrical probe for diagnostics in internal combustion engines. Laser-induced fluorescence (LIF) imaging of fuel, hydroxyl (OH), and nitric oxide (NO) distributions has been employed to extend our knowledge about the governing processes leading to its signal. By monitoring the flame propagation in quiescent and turbulent mixtures, the cycle-to-cycle variations in the e
Minimum weight triangulation by cutting out triangles
We describe a fixed parameter algorithm for computing the minimum weight triangulation (MWT) of a simple polygon with (n - k) vertices on the perimeter and k hole vertices in the interior, that is, for a total of n vertices. Our algorithm is based on cutting out empty triangles (that is, triangles not containing any holes) from the polygon and processing the parts or the rest of the polygon recurs
Linear water waves with vorticity: rotational features and particle paths
Steady linear gravity waves of small amplitude travelling on a current of constant vorticity are found. For negative vorticity we show the appearance of internal waves and vortices, wherein the particle trajectories are not any more closed ellipses. For positive vorticity the situation resembles that of Stokes waves, but for large vorticity the trajectories are affected.
REXEBIS - Design and initial commissioning results
The REXEBIS is an Electron Beam Ion Source (EBIS) developed particularly for charge breeding of rare and short-lived isotopes produced at ISOLDE for the REX-ISOLDE post accelerator. Bunches of singly charged radioactive ions are injected into the EBIS and charge bred to a charge-to-mass ratio of approximately 114 and thereafter extracted and injected into a short LINAC. This novel concept, employi
An in vivo study of the effect of 5-HT and sympathetic nerves on transferrin and transthyretin mRNA expression in rat choroid plexus and meninges
Brain expression of transferrin (Tf) and transthyretin (TTR) mRNA has been demonstrated in different species, TTR being found only in the choroid plexus. We report here that both these mRNAs are also expressed in the meninges. In vitro studies have shown that Tf secretion by the rat choroid plexus is stimulated by 5-hydroxytryptamine (5-HT) while sympathetic nerves regulate different transport fun
Gene expression profile of mouse bone marrow stromal cells determined by cDNA microarray analysis
Bone marrow stromal cells (BMSC) have gained increased attention because of their multipotency and adult stem cell character. They have been shown to differentiate into other cell types of the mesenchymal lineage and also into non-mesenchymal cells. The exact identity of the original cells, which are isolated from bone marrow by their selective adherence to plastic, remains unknown to date. We hav