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Enhanced airway smooth muscle cell thromboxane receptor signaling via activation of JNK MAPK and extracellular calcium influx.

Thromboxane is a key inflammatory mediator and potent airway constrictor. It acts on thromboxane A(2) (TP) receptors and contributes to airway inflammation and airway hyperresponsiveness that is the characteristic feature of asthma. The present study was designed to study TP receptor signaling in airway smooth muscle cells by using an organ culture model and a set of selective pharmacological inhi

High zooplankton diversity in the extreme environments of the McMurdo Dry Valley lakes, Antarctica

The McMurdo Dry Valley lakes of Antarctica constitute some of the harshest and most isolated freshwater environments on Earth which might be expected to limit the biogeographical expansion of many organisms. Despite this, we found that the biodiversity of rotifer zooplankton is the highest ever recorded on the Antarctic mainland. We identified in total nine rotifer taxa, of which six are new to th

Rapid X-ray photoreduction of dimetal-oxygen cofactors in ribonucleotide reductase.

Prototypic dinuclear metal cofactors with varying metallation constitute a class of O2-activating catalysts in numerous enzymes such as ribonucleotide reductase (RNR1). Reliable structures are required to unravel the reaction mechanisms. However, protein crystallography data may be compromised by X-ray photoreduction (XPR). We studied XPR of Fe(III)Fe(III) and Mn(III)Fe(III) sites in the R2 subuni

Methods for the preparation of chlorophyllide a: an intermediate of the chlorophyll biosynthetic pathway

Chlorophyllide a is a metabolite late in the biosynthesis of chlorophylls and bacteriochlorophylls. Isolation procedures for chlorophyllide a from Rhodobacter capsulatus CB1200 and barley (Hordeum vulgare L.) are described and compared. R. capsulatus CB1200 is a double mutant in the bacteriochlorophyllide a biosynthetic pathway, and chlorophyllide a is excreted by the cells when grown in Tween 80-

Dissolution driven crack branching in polycarbonate

Stress corrosion, in the form of chemically assisted crack growth, in polycarbonate is examined with focus on crack branching characteristics. Cracks with finite width are observed; this is to be expected for dissolution driven cracking. The cracks branched repeatedly and crack widths before and after branching are measured. Both symmetric and asymmetric branching is found. The dissolution rate is

Sales Maximization or Profit Maximization? How State Shareholders Discipline their CEOs in China*

This study examines the determinants of Chief Executive Officer (CEO) turnover in Chinese state-owned firms. Based on a sample of 1 555 turnover cases among listed firms in China during the period 19992003, we obtain three main results. First, CEO turnover is negatively related to the sales performance but not the profitability of the core business. Second, the negative relationship between CEO tu

Evidence for SMAD3 as a modifier of breast cancer risk in BRCA2 mutation carriers

Introduction: Current attempts to identify genetic modifiers of BRCA1 and BRCA2 associated risk have focused on a candidate gene approach, based on knowledge of gene functions, or the development of large genome-wide association studies. In this study, we evaluated 24 SNPs tagged to 14 candidate genes derived through a novel approach that analysed gene expression differences to prioritise candidat

Work-related airway symptoms, nasal reactivity and health-related quality of life in female hairdressers: a follow-up study during exposure.

OBJECTIVES: Hairdressers often complain of work-related rhinitis (WR). They are infrequently sensitized to persulphates. The cause and mechanism of the symptoms and the effects on their health-related quality of life (HRQoL) remains unclear. The objectives were to follow female hairdressers with WR mainly from bleaching powder regarding nasal reactivity to persulphate and to evaluate symptoms, HRQ

From millet to tomatoes: incremental intensification with high-value crops in contemporary Meru, Tanzania

In Meru, Tanzania, changing land/labour ratios have, for over a century, been the main driving force in a farm intensification process. The construction and expansion of irrigation systems, increased use of farm inputs and transfer from low- to high-value agricultural crops have enabled smallholders to improve their land productivity. Technological change has been accompanied by institutional chan

Comparison and Evaluation of Multiple Users' Usage of the Exposure and Risk Tool: Stoffenmanager 5.1.

Stoffenmanager is an exposure and risk assessment tool that has a control banding part, with risk bands as outcome and a quantitative exposure assessment part, with the 90th percentile of the predicted exposure as a default outcome. The main aim of the study was to investigate whether multiple users of Stoffenmanager came to the same result when modelling the same scenarios. Other aims were to inv

Predictions of Enhanced Heat Transfer of an Internal Blade Tip-Wall With Hemispherical Dimples or Protrusions

The blade tip region encounters high thermal loads because of the hot gas leakage flows, and it must therefore be cooled to ensure a long durability and safe operation. A common way to cool a blade tip is to design serpentine passages with 180 deg turns under the blade tip-cap inside the turbine blade. Improved internal convective cooling is therefore required to increase the blade tip lifetime. D

Heart rate is associated with progression of atrial fibrillation, independent of rhythm

Objective Atrial fibrillation (AF) often progresses from paroxysmal or persistent to more sustained forms, but the rate and predictors of AF progression in clinical practice are not well described. Methods Using the Outcomes Registry for Better Informed Treatment of AF, we analysed the incidence and predictors of progression and tested the discrimination and calibration of the HATCH (hypertension,

A general criterion for evaporative heat transfer in micro/mini-channels

This paper presents a general criterion to classify a channel as micro-channel or macro-channel. Experimental results of saturated-flow boiling heat transfer in micro/mini-channels for both multi- and single-channel configurations were obtained from the literature. The collected database contains 4228 data points, covering a wide range of working fluids, operational conditions, and different micro

Debt Relief, Investment and Growth

From 1989 to 2004 the donor community provided approximately $400 billion in debt relief to developing countries in an attempt to promote growth and reduce poverty. Using a sample of 118 developing countries, this paper empirically assesses the impact of debt relief on growth via (1) resources made available for investment from reduced debt service payments and (2)improved incentives to invest fro

Characterizing the geometry of InAs nanowires using mirror electron microscopy

Mirror electron microscopy (MEM) imaging of InAs nanowires is a non-destructive electron microscopy technique where the electrons are reflected via an applied electric field before they reach the specimen surface. However strong caustic features are observed that can be non-intuitive and difficult to relate to nanowire geometry and composition. Utilizing caustic imaging theory we can understand an

Valence electronic structure and photofragmentation of 1,1,1,2-tetrafluoroethane (CF3-CH2F)

The electronic structure and fragmentation of the hydrofluorocarbon compound 1,1,1,2-tetrafluoroethane (CF3-CH2F) were studied using spectroscopical methods and quantum chemical calculations. Valence photoelectron spectra and the ionic fragmentation products were recorded with synchrotron radiation in the vacuum ultraviolet (VUV) region. The geometric and electronic structures of the CF3-CH2F mole

Effect of pharmacological treatment for urinary incontinence in the elderly and frail elderly: A systematic review

Aim: The prevalence and severity of urinary incontinence (UI) increase with age and comorbidity. The benefits of pharmacotherapy for UI in the elderly are questionable. The aim of the present study was to systematically review the efficacy of pharmacological treatment for UI in the elderly and frail elderly. Methods: We searched PubMed, EMBASE, Cochrane library and Cinahl databases through October