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Which functional groups of the molybdopterin ligand should be considered when modeling the active sites of the molybdenum and tungsten cofactors? A density functional theory study.

A density functional theory study of the influence of the various functional groups of the molybdopterin ligand on electronic and geometric properties of active-site models for the molybdenum and tungsten cofactors has been undertaken. We used analogous molybdenum and tungsten complexes with increasingly accurate representation of the molybdopterin ligands and compared bond lengths, angles, charge

The route to extinction in variable environments

Estimating the extinction risk of natural populations is not only an urgent problem in conservation biology but also involves some profound aspects of population dynamics. Apart from the obvious case of a continuous decrease in a population's carrying capacity, understanding the extinction process necessarily includes environmental and demographic stochasticity. Here, we build from first principle

Flight speeds among bird species: allometric and phylogenetic effects

Analysing the variation in flight speed among bird species is important in understanding flight. We tested if the cruising speed of different migrating bird species in flapping flight scales with body mass and wing loading according to predictions from aerodynamic theory and to what extent phylogeny provides an additional explanation for variation in speed. Flight speeds were measured by tracking

High predictive value of the Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index for survival in systemic lupus erythematosus.

OBJECTIVE: We previously reported high Systemic Lupus International Collaborating Clinics (SLICC) scores in fatal cases of systemic lupus erythematosus (SLE) from our inception cohort. This study was done to clarify if the SLICC damage scores 5 years after diagnosis predicted the outcome. METHODS: We studied 80 patients with SLE (70 women, 10 men), all enrolled and diagnosed during the years 1981

Kinetics, energetics and specificity of a general amino acid transporter from the ectomycorrhizal fungus Paxillus involutus

The kinetics, energetics and specificity of a general amino acid transporter were studied in the ectomycorrhizal fungus Paxillus involutus (Batsch) Fr. The uptake of amino acids showed features characteristic of active transport. After correction for a non-mediated transport component, the kinetics of glutamate, glutamine, alanine and aspartate uptake measured over a wide concentration range follo

C-14 content in vegetation in the vicinities of Brazilian nuclear power reactors

Abstract in UndeterminedC-14 specific activities were measured in grass samples collected around Brazilian nuclear power reactors. The specific activity values varied between 227 and 299 Bq/kg C. Except for two samples which showed C-14 specific activities 22% above background values, half of the samples showed background specific activities, and the other half had a C-14 excess of 1-18%. The high

Macromolecular geometries determined with field-flow fractionation and their impact on the overlap concentration.

In this paper we aim to understand the size/conformation relationship in waxy barley starch, a polydisperse and ultrahigh molar mass biomacromolecule. Characterizations are performed with asymmetrical flow field-flow fractionation (AsFlFFF). Furthermore, we study the effect of homogenization on the molar mass, rms radius (r rms) and hydrodynamic radius (r h). For the untreated sample, the macromol

Mason type IV fractures of the elbow A 14-TO 46-Year Follow-up Study

A total of 14 women and seven men with a mean age of 43 years (18 to 68) who sustained a Mason type IV fracture of the elbow, without an additional type II or III coronoid fracture, were evaluated after a mean of 21 years (14 to 46). Primary treatment included closed elbow reduction followed by immobilisation in a plaster in all cases, with an additional excision of the radial head in 11, partial

Evaluation of a sulfophenylated polysulfone membrane in a fuel cell at 60 to 110 °C

A novel sulfophenylated polysulfone membrane material has been evaluated in a hydrogen/oxygen fuel cell using Nafion-impregnated commercial electrodes. Comparative measurements were performed with Nafion membranes to distinguish between different sources of potential losses. The operational temperatures in the experiments ranged from 60 to 110 °C, and the effect of different humidifying conditions

Many-body polarization, a cause of asymmetric solvation of ions and quadrupoles

Three models are used to study the effect of many-body polarization in the solvation of non-dipolar molecules and ions in water. Two of the models are very simplified and are used to show a number of basic principles of correlation of solvent degrees of freedom and asymmetric solvent structures. These principles are used to interpret results from the third model: an accurate simulation of para-ben

Detailed definition and interobserver agreement for the electrocardiographic Sclarovsky-Birnbaum ischemia grading system

A generally implementable method for predicting salvageability on the presenting electrocardiogram (ECG) in patients with acute myocardial infarction (AMI) would be of great clinical importance. ECG-derived Grades of Ischemia (1) have been proven useful in predicting the extent and severity of left ventricular dysfunction after anterior MI, estimating short and long-term prognosis, final infarct s

Uterus and endometrium: Flow cytometric DNA analysis in endometriotic tissue compared to normal uterine endometrium

Endometriotic tissue sometimes shows an invasive pattern. but the growth regulation of the tissue is insufficiently characterized. In a research programme on factors regulating endometriotic growth, the DNA ploidy status and S-phase fraction (SPF) were studied. Fresh-frozen endometriotic tissue from 14 women and endometrium from 11 of them were studied using flow cytometry. A clear diploid pattern

Interlaboratory evaluation of endotoxin analyses in agricultural dusts - comparison of LAL assay and mass spectrometry

Endotoxin exposure is associated with wheeze and asthma morbidity, while early life exposure may reduce risk of allergy and asthma. Unfortunately, it is difficult to compare endotoxin results from different laboratories and environments. We undertook this study to determine if lipopolysaccharide ( LPS) extraction efficiency could account for differences among laboratories. We generated and collect

Radiotherapy to Improve Local Control Regardless of Surgical Margin and Malignancy Grade in Extremity and Trunk Wall Soft Tissue Sarcoma: A Scandinavian Sarcoma Group Study

PURPOSE: Adjuvant radiotherapy has during the past decades become increasingly used in the treatment of localized soft tissue sarcoma. We evaluated the effect of radiotherapy (RT) on local recurrence rates (LRRs) in Scandinavia between 1986 and 2005. METHODS AND MATERIALS: A total of 1,093 adult patients with extremity or trunk wall soft tissue sarcoma treated at four Scandinavian sarcoma centers

Metabolically improved exopolysaccharide production by Streptococcus thermophilus and its influence on the rheological properties of fermented milk

Altered levels of enzymes in the central carbon metabolism in Streptococcus thermophilus increased the exopolysaccharide (EPS) production 3.3 times over that of the parent strain. The influence of enhanced EPS production on the rheological properties of fermented milk is described for engineered strains of S. thermophilus which produce different levels of EPSs.

Bacillus bogoriensis sp nov., a novel alkallphilic, halotolerant bacterium isolated from a Kenyan soda lake

Strain LBB3(T) isolated from Bogoria soda lake in Kenya is an alkaliphilic, Gram-positive, strictly aerobic, non-motile, spore-forming bacterium. It was identified as a member of the genus Bacillus on the basis of phenotypic and phylogenetic analyses. The organism grows optimally at 37 degrees C and pH 10. The G+C content of the genomic DNA is 37.5 mol%. 16S rRNA gene sequence analysis showed 95 a