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Influence of the process on phase separation induced by radical copolymerization of styrene and divinylbenzene in the presence of reactive polyurethane network precursors

Interpenetrating polymer systems based on crosslinked polyurethane (PU) and polystyrene (PS) were prepared at room temperature by a one-shot (in situ) method, starting from an initial homogeneous mixture of reagents via noninterfering mechanisms. Both polymerizations were performed either simultaneously or one after the other. True simultaneity at every stages of the process is not possible. Despi

System size and energy dependence of jet-induced hadron pair correlation shapes in Cu+Cu and Au+Au collisions at root S-NN 200 and 62.4 GeV

We present azimuthal angle correlations of intermediate transverse momentum (1-4 GeV/c) hadrons from dijets in Cu+Cu and Au+Au collisions at root s(NN)=62.4 and 200 GeV. The away-side dijet induced azimuthal correlation is broadened, non-Gaussian, and peaked away from Delta phi=pi in central and semicentral collisions in all the systems. The broadening and peak location are found to depend upon th

Major metabolic pathway for N-methyl-2-pyrrolidone in humans

The aim was to study the metabolic pathway for N-methyl-2-pyrrolidone (NMP) in humans. Three healthy male volunteers were administered 100 mg NMP orally. All urine was collected during nine consecutive days. The identification and quantification of the metabolites were performed by gas chromatography/mass spectrometry (GC/MS). NMP, 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP), N-methylsuccinimide (MS

Use of phospholipid fatty acids to detect previous self-heating events in stored peat

The use of the phospholipid fatty acid (PLFA) composition of microorganisms to detect previous self-heating events was studied in naturally self-heated peat and in peat incubated under temperature-controlled conditions. An increased content of total PLFAs was found in self-heated peat compared to that in unheated peat. Two PLFAs, denoted T1 and T2, were detected only in the self-heated peat. Incub

Analysis of phenoxyacetic acid herbicides as biomarkers in human urine using liquid chromatography triple quadrupole mass spectrometry.

Phenoxyacetic acids are widely used herbicides. The toxicity of phenoxyacetic acids is debated, but high-level exposure has been shown to be hepatotoxic as well as nephrotoxic in animal studies. An inter-species difference in toxic effects has been found, with dogs particularly susceptible. In this study a method using liquid chromatography/triple quadrupole mass spectrometry (LC/MS/MS) is describ

A comparison of two recorders for obtaining in-flight heart rate data

Measurement of mental workload has been widely used for evaluation of aircraft design, mission analysis and assessment of pilot performance during flight operations. Heart rate is the psychophysiological measure that has been most frequently used for this purpose. The risk of interference with flight safety and pilot performance, as well as the generally constrained access to flights, make it diff

Increased claudin-4 expression is associated with poor prognosis and high tumour grade in breast cancer

The role of intercellular tight junctions in breast epithelia[ cells is traditionaliy thought to be in maintaining polarity and barrier function. However, claudin-4, a tight junction protein, is overexpressed in breast tumour cells compared to normal epithelial cells, which generally corresponds to a loss in polarity. The aim of this study was to investigate the distribution and potential clinical

Relative importance of burning, mowing and species translocation in the restoration of a former boreal hayfield: responses of plant diversity and the microbial community

1. The extensive loss of species-rich grasslands in Europe as a result of agricultural intensification has triggered a desire to recreate more diverse and natural grassland systems in set-aside fields. Appropriate management and species introductions are necessary to overcome residual soil fertility, lack of suitable plant propagules and dominance of undesirable invasive species. 2. A field experi

Monitoring and control of an anaerobic upflow fixed-bed reactor for high-loading-rate operation and rejection of disturbances

A new control strategy has been introduced for operating anaerobic digestion processes efficiently at high load. The control system includes a cascade controller embedded into a rule-based supervisory system based on extremum-seeking control. Three process parameters, considered to be the most realistic variables for monitoring of the bioprocess, were selected (pH, biogas production rate, and the

Disposition of venlafaxine enantiomers in rats with hepatic encephalopathy after chronic drug treatment.

Portacaval shunted (PCS) rats, a model of hepatic encephalopathy, and control animals were administered racemic venlafaxine for 14 days (10 mg/kg). The levels of the S- and R-enantiomers and the S/R-enantiomer ratios of venlafaxine and its metabolites were assessed by an enantiomer-selective chromatographic assay in serum, brain parenchyma, and brain dialysate of both groups. Higher levels of the

Tumour microvessel density as predictor of chemotherapy response in breast cancer patients

The aim of this study was to evaluate the predictive value of intratumoural microvessel density in breast cancer. We studied immunohistochemically primary tumours of 104 patients with metastasised breast cancer who took part in a randomised multicentre trial comparing docetaxel to sequential methotrexate and 5-fluorouracil. Vessels were highlighted with factor VIII staining and counted microscopic

Synthesis and biology of bis-xylosylated dihydroxynaphthalenes.

The 10 analogous bis-xylosylated dihydroxynaphthalenes have been synthesized and their chemical and biological properties investigated. The yield of the xylosylation reactions can be correlated to the electrostatic potential, and thus to the nucleophilicity, for the oxygen atoms of the dihydroxynaphthalenes. The bis-xylosylated compounds were more stable compared to the mono-xylosylated ones. They

Rapid Holocene climate changes in the North Atlantic: evidence from lake sediments from the Faroe Islands

Holocene records from two lakes on the Faroe Islands were investigated to determine regional climatic variability: the fairly wind-exposed Lake Starvatn on Streymoy and the more sheltered Lake Lykkjuvotn on Sandoy. Sediment cores were analysed for content of biogenic silica, organic carbon and clastic material, and magnetic susceptibility. In addition, a new qualitative proxy for past lake ice cov

Structure of the Bifunctional dCTP Deaminase-dUTPase from Methanocaldococcus jannaschii and Its Relation to Other Homotrimeric dUTPases

The bifunctional dCTP deaminase-dUTPase (DCD-DUT) from Methanocaldococcus jannaschii catalyzes the deamination of the cytosine moiety in dCTP and the hydrolysis of the triphosphate moiety forming dUMP, thereby preventing uracil from being incorporated into DNA. The crystal structure of DCD-DUT has been determined to 1.88-Å resolution and represents the first known structure of an enzyme catalyzing

Effects of anti-secretory factor (ASF) on irritable bowel syndrome (IBS)

Objective. To evaluate the role of the endogenous protein anti-secretory factor (ASF) on the symptoms, especially loose stools, in irritable bowel ayndrome (IBS). Design. A diet with specially processed cereals (SPC) known to induce ASF production was used in patients with IBS, in an eight-week randomized, placebo-controlled study. Subjects. Eighty-two patients with IBS were randomized to a diet w

Epostane in nonpregnant females: effects on progesterone, 17 alpha-hydroxyprogesterone, and 17 beta-estradiol of two dose levels given for one month

So far, the use of epostane, a relatively new inhibitor of 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase enzyme system (3 beta-HSD), has been confined to short-term interference with luteal and placental function. This study explored whether epostane treatment from the beginning of the cycle for approximately 1 month would also inhibit ovarian follicular function. Twenty females wi

Neutrophil cannibalism--a back up when the macrophage clearance system is insufficient.

Background: During a lipopolysaccharide-induced lung inflammation, a massive accumulation of neutrophils occurs, which is normally cleared by macrophage phagocytosis following neutrophil apoptosis. However, in cases of extensive apoptosis the normal clearance system may fail, resulting in extensive neutrophil secondary necrosis. The aim of this study was to explore the hypothesis that neutrophils,