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Transition probabilities and lifetimes in singly ionized rhenium

Transition probabilities and radiative lifetimes have been obtained for 45 transitions of Re II using a combination of radiative lifetime values obtained with the laser-induced fluorescence technique ( seven levels) and theoretical branching fractions. This new set of results, concerning ultraviolet and visible lines, will be useful in the future for investigating the composition of chemically pec

Carotid artery stenosis: contrast-enhanced MR angiography with two different scan times compared with digital subtraction angiography

Contrast enhanced magnetic resonance angiography (CE MRA) is a non-invasive alternative to conventional digital subtraction angiography (DSA). CE MRA is increasingly used as a complement to Duplex in the preoperative assessment of carotid artery stenosis. The purpose of this study was to determine if CE MRA could replace preoperative DSA. CE MRA with a scan time of 10 or 28 s was performed in 24 c

Application of the Selective Energy Transfer Model to Account for an Isokinetic Response in the Gas Phase Reductive Cleavage of Hydroxyl, Carbonyl and Carboxyl Groups from Benzene Over Nickel/Silica

The gas phase hydrodeoxygenation of a series of aromatic alcohols, aldehydes and acids has been examined over Ni/SiO2. Compensation behaviour is established with an isokinetic temperature (518 +/- A 21 K) that is consistent with with the point of intersection of the Arrhenius lines. This is accounted for using the Selective Energy Transfer model that is based on resonance between the catalytic Ni-

The presence of elafin, SLPI, IL1-RA and STNFalpha RI in head and neck squamous cell carcinomas and their relation to the degree of tumour differentiation.

Biopsy samples of head and neck carcinomas were investigated with regard to elafin, secretory leukocyte protease inhibitor (SLPI), interleukin 1-receptor antagonist [(IL)1-RA] and soluble tumour necrosis factor alpha receptor antagonist (STNFalpha RI). SLPI and elafin are serine protease inhibitors produced in the serous cells of the upper respiratory airways and in the keratinocytes, respectively

Simvastatin stimulates macrophage interleukin-1beta secretion through an isoprenylation-dependent mechanism.

Statin treatment inhibits oxidized lipoprotein-induced intracellular lipid accumulation (foam cell formation) and reduces plasma levels of inflammatory markers such as interleukin-1 beta The aim of the present study was to determine if simvastatin affected lipid accumulation in macrophages incubated with aggregated low density lipoproteins (AgLDL) and whether simvastatin had a direct effect on cyt

Cerebral haemodynamic and metabolic effects of hypnotics and analgesics

Abstract in French La sédation des patients neurochirurgicaux fait appel le plus souvent à une association hypnotique-analgésique. Leurs effets sur l'hémodynamique et le métabolisme cérébraux sont l'un des critères qui président au choix des produits. Les analgésiques utilisés seuls, ont peu d'effets sur le flux sanguin cérébral et la CMRO2. Certaines données de la littérature attribuent aux analg

The influence of time-dependent melting on the dynamics and precipitation production in maritime and continental storm clouds

Simulations of one maritime and four continental observed cases of deep convection are performed with the Hebrew University Cloud Model that has spectral bin microphysics. The maritime case is from observations made on 18 September 1974 during the Global Atmospheric Research Program's Atlantic Tropical Experiment ( GATE). The continental storm cases are those of summertime Texas clouds observed on

Toward understanding nonparticipation in sigmoidoscopy screening for colorectal cancer

Understanding the reasons for nonparticipation in cancer screening may give clues about how to improve compliance. However, limited cooperation has hampered research on nonparticipant profiles. We took advantage of Sweden's comprehensive demographic and health care registers to investigate characteristics of all participants and nonparticipants in a pilot program for colorectal cancer screening wi

Interatrial conduction in the mechanisms of atrial fibrillation: from anatomy to cardiac signals and new treatment modalities.

Areas of slow conduction and conduction block are important prerequisites for re-entry known to underlie atrial fibrillation (AF). Experimental and clinical data show that AF is associated with global lowering of atrial propagation velocity and the presence of defects in the interatrial conduction routes. The increasing data from anatomical studies demonstrate the possible prerequisites for conduc

Accelerator mass spectrometry - an overview

The technique of accelerator mass spectrometry (AMS) has spread worldwide since its first demonstration 25 years ago. The equipment used today is very diverse and dedicated accelerators as well as old "nuclear physics machines" can be found in the nearly 50 AMS laboratories today. The most widely spread application of AMS is for radiocarbon dating. However, AMS with C-14 as well as with other long

Effects of data uncertainty in Swedish critical load assessment for forest soils.

The effects of input data uncertainty on the critical loads and exceedance estimates for Swedish forest soils was assessed using Monte Carlo simulations of the PROFILE model. The study focuses on the effects of data uncertainty on the 5%-ile critical load at 150 × 150 km resolution and the 95%-ile exceedance at 150 × 150 km and 50 × 50 km resolution. The results indicate that data uncertainty limi

Histologic and Manometric Studies on the Esophagus Following Endoscopic Sclerotherapy

Objective The aim of this work was to study the histologic and manometric changes in the distal esophagus beyond 2 years following endoscopic sclerotherapy (EST) and/or surgical intervention, and to try to understand the etiological factors associated with these changes. Patients and interventions Forty patients, with an average age of 61.5 years, were studied for 2-12 years following sclerotherap

Gaussian Mixture Kalman Predictive Coding of Line Spectral Frequencies

Gaussian mixture model (GMM)-based predictive coding of line spectral frequencies (LSFs) has gained wide acceptance. In such coders, each mixture of a GMM can be interpreted as defining a linear predictive transform coder. In this paper, we use Kalman filtering principles to model each of these linear predictive transform coders to present GMM Kalman predictive coding. In particular, we show how s

Accelerated exchange of a buried water molecule in selectively disulfide-reduced bovine pancreatic trypsin inhibitor.

Using magnetic relaxation dispersion (MRD), we have previously shown that the four internal water molecules in bovine pancreatic trypsin inhibitor (BPTI) exchange with bulk water on time scales between 10(-8) and 10(-4) s at room temperature. Because this exchange is controlled by the protein structure, internal water molecules can be used to probe rare conformational fluctuations. Here, we report

The breast cancer-associated gene Di12 has oncogenic activity

The breast cancer-associated gene Di12 encodes a novel protein, which was found overexpressed in invasive ductal carcinomas of the breast. In experiments designed to assess the role of the Di12 gene in oncogenesis, the overexpression of 339 N-terminal amino acids of this gene in NIH3T3 cells resulted in cellular transformation and in vivo tumorigenesis. NIH3T3-Di12 tumor cell growth was partly rev

Heme-Scavenging Role of alpha1-Microglobulin in Chronic Ulcers.

Chronic venous ulcers are characterized by chronic inflammation. Heme and iron, originating from blood cell hemolysis as well as extravascular necrosis, have been implicated as important pathogenic factors due to their promotion of oxidative stress. It was recently reported that the plasma and tissue protein alpha1-microglobulin is involved in heme metabolism. The protein binds heme, and a carboxy

Inorganic ligand effects on Pb(II) sorption to goethite (alpha-FeOOH) - II. Sulfate

The effects of sulfate anions on the uptake of Pb(II) onto goethite were investigated at the molecular level using in situ Pb L-III-EXAFS and ATR-FTIR spectroscopies. Macroscopic uptake data show that Pb uptake can be enhanced by at least 30% at pH 5 in the presence of 3.16 mM sulfate and that sulfate uptake at pH 7 can be enhanced by more than a factor of 3 in the presence of 1.0 mM Pb. Consisten