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Melanosomes and ancient coloration re-examined: A response to Vinther 2015 (DOI 10.1002/bies.201500018).

Round to elongate microbodies associated with fossil vertebrate soft tissues were interpreted as microbial traces until 2008, when they were re-described as remnant melanosomes - intracellular, pigment-containing eukaryotic organelles. Since then, multiple claims for melanosome preservation and inferences of organismal color, behavior, and physiology have been advanced, based upon the shape and si

Multiexciton Absorption Cross Sections of CdSe Nanocrystals at Band-Edge Energy

Picosecond transient absorption signals of two kinds of cadmium selenide quantum dots were measured at various excitation intensities. The average number of excitons per quantum dot was calculated from a Poisson model, which together with kinetic parameters was used to determine exciton population kinetics. Exciton and multiexciton absorption cross sections were determined and analyzed in terms of

Are homology models sufficiently good for free-energy simulations?

In this paper, I evaluate the usefulness of protein homology models in rigorous free-energy simulations to determine ligand affinities. Two templates were used to create models of the factor Xa protein and one template was used for dihydrofolate reductase from Plasmodium falciparum. Then, the relative free energies for several pairs of ligands were estimated using thermodynamic integration with th

The outcome of allo-HSCT for 92 patients with myelofibrosis in the Nordic countries

Between 1982 and 2009 a total of 92 patients with myelofibrosis (MF) in chronic phase underwent allo-SCT in nine Nordic transplant centers. Myeloablative conditioning (MAC) was given to 40 patients, and reduced intensity conditioning (RIC) was used in 52 patients. The mean age in the two groups at transplantation was 46 +/- 12 and 55 +/- 8 years, respectively (P

Calcium-Dependent Interaction of Calmodulin with Human 80S Ribosomes and Polyribosomes.

Ribosomes are the protein factories of every living cell. The process of protein translation is highly complex and tightly regulated by a large number of diverse RNAs and proteins. Earlier studies indicate that Ca(2+) plays a role in protein translation. Calmodulin (CaM), a ubiquitous Ca(2+)-binding protein, regulates a large number of proteins participating in many signaling pathways. Several 40S

On Flow Maldistribution in PEMFC Stacks

Polymer electrolyte membrane fuel cell (PEMFC) stacks are widely studied for their own advantages. The flow maldistribution in unit cells may severely influence the fuel cell stack performance, mainly including the uniformity of current density and the voltage. Investigations of flow maldistribution in PEMFC stacks are rarely found, and presented results are unsystematic, scattered, and even contr

Search for Scalar Bottom Quark Pair Production with the ATLAS Detector in pp Collisions at root s=7 TeV

The results of a search for pair production of the scalar partners of bottom quarks in 2: 05 fb(-1) of pp collisions at root s = 7 TeV using the ATLAS experiment are reported. Scalar bottom quarks are searched for in events with large missing transverse momentum and two jets in the final state, where both jets are identified as originating from a bottom quark. In an R-parity conserving minimal sup

Wild-type MIC distributions of four fluoroquinolones active against Mycobacterium tuberculosis in relation to current critical concentrations and available pharmacokinetic and pharmacodynamic data

To describe wild-type distributions of the MIC of fluoroquinolones for Mycobacterium tuberculosis in relation to current critical concentrations used for drug susceptibility testing and pharmacokinetic/pharmacodynamic (PK/PD) data. A 96-stick replicator on Middlebrook 7H10 medium was used to define the MICs of ciprofloxacin, ofloxacin, moxifloxacin and levofloxacin for 90 consecutive clinical stra

Monogenic Parkinson's disease and parkinsonism: Clinical phenotypes and frequencies of known mutations.

Mutations in seven genes are robustly associated with autosomal dominant (SNCA, LRRK2, EIF4G1, VPS35) or recessive (parkin/PARK2, PINK1, DJ1/PARK7) Parkinson's disease (PD) or parkinsonism. Changes in a long list of additional genes have been suggested as causes for parkinsonism or PD, including genes for hereditary ataxias (ATXN2, ATXN3, FMR1), frontotemporal dementia (C9ORF72, GRN, MAPT, TARDBP)

High Serum Testosterone Is Associated With Reduced Risk of Cardiovascular Events in Elderly Men The MrOS (Osteoporotic Fractures in Men) Study in Sweden

Objectives We tested the hypothesis that serum total testosterone and sex hormone-binding globulin (SHBG) levels predict cardiovascular (CV) events in community-dwelling elderly men. Background Low serum testosterone is associated with increased adiposity, an adverse metabolic risk profile, and atherosclerosis. However, few prospective studies have demonstrated a protective link between endogenous

FVIII inhibitors: pathogenesis and avoidance.

The pathogenesis of inhibitory antibodies has been the focus of major scientific interest over the last decades and several studies on underlying immune mechanisms and risk factors for formation of these antibodies have been performed with the aim of improving the ability to both predict and prevent their appearance. It seems clear that the decisive factors for the immune response to the deficient

Inverse association of intellectual function with very low blood lead but not with manganese exposure in Italian adolescents

Background: Pediatric lead (Pb) exposure impacts cognitive function and behavior and co-exposure to manganese (Mn) may enhance neurotoxicity. Objectives: To assess cognitive and behavioral function in adolescents with environmental exposure to Pb and Mn. Methods: In this cross sectional study, cognitive function and behavior were examined in healthy adolescents with environmental exposure to metal

Sex Pheromone Evolution Is Associated with Differential Regulation of the Same Desaturase Gene in Two Genera of Leafroller Moths

Chemical signals are prevalent in sexual communication systems. Mate recognition has been extensively studied within the Lepidoptera, where the production and recognition of species-specific sex pheromone signals are typically the defining character. While the specific blend of compounds that makes up the sex pheromones of many species has been characterized, the molecular mechanisms underpinning

Low Leakage-Current InAsSb Nanowire Photodetectors on Silicon.

Axially doped p-i-n InAs0.93Sb0.07 nanowire arrays have been grown on Si substrates and fabricated into photodetectors for shortwave infrared detection. The devices exhibit a leakage current density around 2 mA/cm(2) and a 20% cutoff of 2.3 μm at 300 K. This record low leakage current density for InAsSb based devices demonstrates the suitability of nanowires for the integration of III-V semiconduc

Optimizing A Readout Protocol For Low Dose Retrospective Osl-Dosimetry Using Household Salt

The authors' aim has been to find a single aliquot regenerative dose (SAR) protocol that accurately recovers an unknown absorbed dose in the region between 1-250 mGy in household salt. The main investigation has been conducted on a specific mine salt (>98.5% NaCl) intended for household use, using optical stimulation by blue LED (lambda = 462 nm). The most accurate dose recovery for this brand of

Quantification of microscopic diffusion anisotropy disentangles effects of orientation dispersion from microstructure: Applications in healthy volunteers and in brain tumors

The anisotropy of water diffusion in brain tissue is affected by both disease and development. This change can be detected using diffusion MRI and is often quantified by the fractional anisotropy (FA) derived from diffusion tensor imaging (DTI). Although FA is sensitive to anisotropic cell structures, such as axons, it is also sensitive to their orientation dispersion. This is a major limitation t

Clinical review: Continuous and simplified electroencephalography to monitor brain recovery after cardiac arrest.

There has been a dramatic change in hospital care of cardiac arrest survivors in recent years, including the use of target temperature management (hypothermia). Clinical signs of recovery or deterioration, which previously could be observed, are now concealed by sedation, analgesia, and muscle paralysis. Seizures are common after cardiac arrest, but few centers can offer high-quality electroenceph

The Effects of Climate Change on Cardiac Health

The earth's climate is changing and increasing ambient heat levels are emerging in large areas of the world. An important cause of this change is the anthropogenic emission of greenhouse gases. Climate changes have a variety of negative effects on health, including cardiac health. People with preexisting medical conditions such as cardiovascular disease (including heart failure), people carrying o