724 research outputs found
Thermal diffusion by Brownian motion induced fluid stress
The Ludwig-Soret effect, the migration of a species due to a temperature
gradient, has been extensively studied without a complete picture of its cause
emerging. Here we investigate the dynamics of DNA and spherical particles sub
jected to a thermal gradient using a combination of Brownian dynamics and the
lattice Boltzmann method. We observe that the DNA molecules will migrate to
colder regions of the channel, an observation also made in the experiments of
Duhr, et al[1]. In fact, the thermal diffusion coefficient found agrees
quantitatively with the experimental value. We also observe that the thermal
diffusion coefficient decreases as the radius of the studied spherical
particles increases. Furthermore, we observe that the thermal
fluctuations-fluid momentum flux coupling induces a gradient in the stress
which leads to thermal migration in both systems.Comment: 6 pages, 5 figue
Distributed multi-task classification: A decentralized online learning approach
National Research Foundation (NRF) Singapore under IDM Futures Funding Initiativ
Impact on the Quality of Life of an Educational Program for the Prevention of Work-Related Musculoskeletal Disorders: a randomized controlled trial
<p>Abstract</p> <p>Background</p> <p>Work-related musculoskeletal disorders (WMSD) are a major cause for concern in public health and the main causes of sick leave. Treatments for WMSD have given disappointing results; prevention is the best strategy, but results of preventive measures have not been consistent. To the best of our knowledge there are few studies in literature that evaluated the impact of a specific program aimed at preventing WMSD on the quality of life of employed persons.</p> <p>Methods</p> <p>One hundred and one clerical and production workers in a steel trading company were enrolled in an open-label randomized controlled clinical trial (parallel groups) to compare the efficacy of an educational program for primary prevention of WMSD with control intervention. The primary outcome was a change in the physical functioning domain of the quality of life (QL) measured by Medical Outcomes Study Short Form 36 Health Survey (SF-36). The intervention group underwent six consecutive weekly sessions concerning specific orientations for the prevention of WMSD, while the control group received general health education in an identical schedule. The SF-36 and theses Work Limitation Questionnaire (WLQ) were evaluated at weeks zero, five and 26.</p> <p>Results</p> <p>Baseline characteristics of the interventions groups were comparable, and both groups comprised predominantly young healthy individuals. No significant differences in the variation of the SF-36 and WLQ between the groups were observed at weeks five and 26. However, both groups demonstrated improvement in some aspects of SF-36, suggesting that both educational interventions have beneficial impacts on QL.</p> <p>Conclusions</p> <p>A specific educational program aimed at the preventing of WMSD was comparable with general health orientation for the improvement of QL and work capacity in a sample of healthy workers during a six month period.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00981877">NCT00874718</a></p> <p>Trial Registration</p
Schistosomes Induce Regulatory Features in Human and Mouse CD1dhi B Cells: Inhibition of Allergic Inflammation by IL-10 and Regulatory T Cells
Chronic helminth infections, such as schistosomes, are negatively associated with allergic disorders. Here, using B cell IL-10-deficient mice, Schistosoma mansoni-mediated protection against experimental ovalbumin-induced allergic airway inflammation (AAI) was shown to be specifically dependent on IL-10-producing B cells. To study the organs involved, we transferred B cells from lungs, mesenteric lymph nodes or spleen of OVA-infected mice to recipient OVA-sensitized mice, and showed that both lung and splenic B cells reduced AAI, but only splenic B cells in an IL-10-dependent manner. Although splenic B cell protection was accompanied by elevated levels of pulmonary FoxP3+ regulatory T cells, in vivo ablation of FoxP3+ T cells only moderately restored AAI, indicating an important role for the direct suppressory effect of regulatory B cells. Splenic marginal zone CD1d+ B cells proved to be the responsible splenic B cell subset as they produced high levels of IL-10 and induced FoxP3+ T cells in vitro. Indeed, transfer of CD1d+ MZ-depleted splenic B cells from infected mice restored AAI. Markedly, we found a similarly elevated population of CD1dhi B cells in peripheral blood of Schistosoma haematobium-infected Gabonese children compared to uninfected children and these cells produced elevated levels of IL-10. Importantly, the number of IL-10-producing CD1dhi B cells was reduced after anti-schistosome treatment. This study points out that in both mice and men schistosomes have the capacity to drive the development of IL-10-producing regulatory CD1dhi B cells and furthermore, these are instrumental in reducing experimental allergic inflammation in mice
Effect of cobalt substitution on microstructure and magnetic properties in ZnO nanoparticles
Polymorphisms near TBX5 and GDF7 are associated with increased risk for Barrett's esophagus.
BACKGROUND & AIMS: Barrett's esophagus (BE) increases the risk of esophageal adenocarcinoma (EAC). We found the risk to be BE has been associated with single nucleotide polymorphisms (SNPs) on chromosome 6p21 (within the HLA region) and on 16q23, where the closest protein-coding gene is FOXF1. Subsequently, the Barrett's and Esophageal Adenocarcinoma Consortium (BEACON) identified risk loci for BE and esophageal adenocarcinoma near CRTC1 and BARX1, and within 100 kb of FOXP1. We aimed to identify further SNPs that increased BE risk and to validate previously reported associations. METHODS: We performed a genome-wide association study (GWAS) to identify variants associated with BE and further analyzed promising variants identified by BEACON by genotyping 10,158 patients with BE and 21,062 controls. RESULTS: We identified 2 SNPs not previously associated with BE: rs3072 (2p24.1; odds ratio [OR] = 1.14; 95% CI: 1.09-1.18; P = 1.8 × 10(-11)) and rs2701108 (12q24.21; OR = 0.90; 95% CI: 0.86-0.93; P = 7.5 × 10(-9)). The closest protein-coding genes were respectively GDF7 (rs3072), which encodes a ligand in the bone morphogenetic protein pathway, and TBX5 (rs2701108), which encodes a transcription factor that regulates esophageal and cardiac development. Our data also supported in BE cases 3 risk SNPs identified by BEACON (rs2687201, rs11789015, and rs10423674). Meta-analysis of all data identified another SNP associated with BE and esophageal adenocarcinoma: rs3784262, within ALDH1A2 (OR = 0.90; 95% CI: 0.87-0.93; P = 3.72 × 10(-9)). CONCLUSIONS: We identified 2 loci associated with risk of BE and provided data to support a further locus. The genes we found to be associated with risk for BE encode transcription factors involved in thoracic, diaphragmatic, and esophageal development or proteins involved in the inflammatory response
Uso de análise espectral e regras de filtragem em operações com contratos futuros de soja no Brasil
Associação entre caracterÃsticas pessoais, organização do trabalho e presença de dor em funcionários de uma indústria moveleira
- …