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Numerical investigation of fluid flow structure and heat transfer in a passage with continuous and truncated V-shaped ribs

Purpose - The employment of continuous ribs in a passage involves a noticeable pressure drop penalty, while other studies have shown that truncated ribs may provide a potential to reduce the pressure drop while keeping a significant heat transfer enhancement. The purpose of this paper is to perform computer-aided simulations of turbulent flow and heat transfer of a rectangular cooling passage with

Evidence for past variations in methane availability in a Siberian thermokarst lake based on delta C-13 of chitinous invertebrate remains

Understanding past methane dynamics in arctic wetlands and lakes is crucial for estimating future methane release. Methane fluxes from lake ecosystems have increasingly been studied, yet only few reconstructions of past methane emissions from lakes are available. In this study, we develop an approach to assess changes in methane availability in lakes based on delta C-13 of chitinous invertebrate r

Properties and degradation of hydrocarbon fuel cell membranes: a comparative study of sulfonated poly(arylene ether sulfone)s with different positions of the acid groups

Sulfonated fully aromatic polymers with different positions of the acid groups, but with an identical polymer backbone, have been investigated and compared with respect to their properties as proton-exchange membranes. Three different series of sulfonated poly(arylene ether sulfone)s (SPAES) having the same backbone structure were prepared from 4,4’-dichlorodiphenyl sulfone (DCDPS) and 4,4’-dihydr

Psychometric properties and factor structure of the Swedish version of the Perceived Stress Scale.

Background: The Perceived Stress Scale (PSS) measures general stress and the Swedish version, although used in several studies, has not been extensively evaluated for psychometric properties. Aims: This study aimed to investigate psychometric properties and the factor solution of the Swedish 14-item version when used with two samples, namely a mixed Internet sample of women and men (n = 171) and a

Spectral properties of higher order Anharmonic Oscillators

We discuss spectral properties of the selfadjoint operator−d 2 dt 2 +t k+1 k+1 − α 2 in L 2 (R ) for odd integers k. We prove that the minimum over α of the ground state energy of this operator is attained at a unique point which tends to zero ask tends to infinity. We also show that the minimum is nondegenerate. These questions arise naturally in the spectral analysis of Schr ̈odinger operators w

A variational formulation for interpolation of seismic traces with derivative information

We construct a variational formulation for the problem of interpolating seismic data in the case of missing traces. We assume that we have derivative information available at the traces. The variational problem is essentially the minimization of the integral over the smallest eigenvalue of the structure tensor associated with the interpolated data. This has the physical meaning of penalizing the l

Comprehensive mathematical model for biomass combustion

This article reports on an investigation of a comprehensive mathematical model for biomass combustion within the one-dimensional model framework. The model takes into account different thermochemical processes, e.g., moisture evaporation, pyrolysis, heterogeneous char reactions, intra-particle heat and mass transfer, and changes in thermo-physical properties. Different approaches to model the vari

Three Redundant Synthetases Secure Redox-Active Pigment Production in the Basidiomycete Paxillus involutus.

The symbiotic fungus Paxillus involutus serves a critical role in maintaining forest ecosystems, which are carbon sinks of global importance. P. involutus produces involutin and other 2,5-diarylcyclopentenone pigments that presumably assist in the oxidative degradation of lignocellulose via Fenton chemistry. Their precise biosynthetic pathways, however, remain obscure. Using a combination of bioch

The 2011 outcome from the Swedish Health Care Registry on Heart Disease (SWEDEHEART).

Abstract Objectives. The Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART) collects data to support the improvement of care for heart disease. Design. SWEDEHEART collects on-line data from consecutive patients treated at any coronary care unit n = (74), followed for secondary prevention, undergoing a

Measurements of the top quark branching ratios into channels with leptons and quarks with the ATLAS detector

Measurements of the branching ratios of top quark decays into leptons and jets using events with t (t) over bar ( top antitop) pairs are reported. Events were recorded with the ATLAS detector at the LHC in pp collisions at a center-of-mass energy of 7 TeV. The collected data sample corresponds to an integrated luminosity of 4.6 fb(-1). The measured top quark branching ratios agree with the Standar

Traumatic experiences and somatoform dissociation among spirit possession practitioners in the Dominican Republic

Recent studies in African contexts have revealed a strong association between spirit possession and severe trauma, with inclusion into a possession cult serving at times a therapeutic function. Research on spirit possession in the Dominican Republic has so far not included quantitative studies of trauma and dissociation. This study evaluated demographic variables, somatoform dissociative symptoms,

Voids and Mn-rich inclusions in a (Ga,Mn)As ferromagnetic semiconductor investigated by transmission electron microscopy

Voids adjacent to cubic (ZnS-type) and hexagonal (NiAs-type) Mn-rich nanocrystals are characterized using aberration-corrected transmission electron microscopy in an annealed Ga(0.995)Mn(0.005)As magnetic semiconductor specimen grown by molecular beam epitaxy. Nanobeam electron diffraction measurements suggest that the nanocrystals exhibit deviations in lattice parameter as compared to bulk MnAs.

Early adrenaline administration does not improve circulatory recovery during resuscitation from severe asphyxia in newborn piglets.

AIM OF THE STUDY: : To investigate the effects of early intravenous adrenaline administration on circulatory recovery, cerebral reoxygenation, and plasma catecholamine concentrations, after severe asphyxia-induced bradycardia and hypotension. METHODS: One-day old piglets were left in apnoea until heart rate and mean arterial pressure were less than 50min(-1) and 25mmHg, respectively. They random

Loss-of-Function Mutations in APOC3, Triglycerides, and Coronary Disease

Background Plasma triglyceride levels are heritable and are correlated with the risk of coronary heart disease. Sequencing of the protein-coding regions of the human genome (the exome) has the potential to identify rare mutations that have a large effect on phenotype. Methods We sequenced the protein-coding regions of 18,666 genes in each of 3734 participants of European or African ancestry in the

Biological vs Conventional Combination Treatment and Work Loss in Early Rheumatoid Arthritis A Randomized Trial

IMPORTANCE The introduction of biological tumor necrosis factor inhibitors has improved the treatment of rheumatoid arthritis (RA) but at a substantial cost. These drugs have been shown to lead to superior radiological outcomes compared with a combination of conventional disease-modifying antirheumatic drugs over 2 years. OBJECTIVE To investigate whether radiological superiority translates into be

Zinc transporter 8 autoantibodies in patients with type 1 diabetes from a multiethnic population and their first degree relatives.

Objective Zinc transporter 8 autoantibodies (ZnT8A) have been poorly studied in non-Caucasian individuals. We aimed to investigate the prevalence of ZnT8 autoantibodies in patients with T1D and their first degree relatives (FDR) from a multiethnic population, as well as its relation with the insulin (INS) or the protein tyrosine phosphatase non-receptor 22 (PTPN22) gene polymorphisms. Subjects and

Collisional broadening and spectral shapes of absorption lines of free and nanopore-confined O-2 gas

This paper presents fully ab initio calculations of the broadenings and spectral shapes of O-2 infrared absorption lines in a free gas and when confined in nanoporous media. These calculations are performed, without use of any adjusted parameter, using a recently proposed approach [Phys. Rev. A 87, 013403 (2013)] that is based on requantized classical molecular-dynamics simulations. This involves