2,040 research outputs found

    Local hydrodynamics investigation within a dynamic filtration unit under laminar flow

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    Conference: 9th International Symposium on Mixing in Industrial ProcessesLocation: Birmingham, ENGLANDDate: JUN 25-28, 2017A dynamic filtration module, called a Rotating and Vibrating Filtration (R.V.F.) module, was designed and dedicated to the treatment of highly viscous fluid, such as fermentation broth or liquid food. To this end, an experimental study was undertaken, using a laminar flow regime with a viscous Newtonian model fluid in a dynamic filtration module in order to quantify the effect of local hydrodynamics on filtration. Instantaneous velocity fields can be measured and analyzed within an R.V.F. by using Particle Image Velocimetry (P.I.V.). In this study, we applied P.I.V. to study the laminar local hydrodynamics in 3 different slices within the 3 mm gap between the membrane and the impeller and 3 vertical slices at different radial positions, with rotation speeds from 0 to 10 Hz. Radial and vertical profiles of tangential velocity were then plotted. Proper Orthogonal Decomposition (P.O.D.) was applied to the P.I.V. data to discriminate between mean flow and fluctuating velocities induced by the periodic motion of the impeller. Thus, viscous shear stress profiles were deduced in terms of both mean shear stress profile and root mean squared (r.m.s.) fluctuating shear stress profile; wall values were then deduced. With this approach, we were able to quantify the distribution of viscous shear stress at the wall (membrane), in terms of mean value and r.m.s. contribution. Dynamic filtration efficiency was thus enlightened by local hydrodynamics. (C) 2018 Institution of Chemical Engineers

    Preferred Features of E-Mental Health Programs for Prevention of Major Depression in Male Workers: Results From a Canadian National Survey

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    Background: Major depression is a prevalent mental disorder and imposes considerable burden on health and productivity. Men are not immune to major depression, yet they often delay seeking help because of perceived stigma and gender norms. E-mental health programs hold potential for early prevention of major depression. However, we have little knowledge about men\u27s preferences for design features of e-mental health programs. Objectives: The objective of this study was to (1) estimate and compare the proportions of Internet use for medical information, preferred design features, and likely use of e-mental health programs; (2) examine factors associated with the likely use of e-mental health programs; and (3) understand potential barriers to the use of e-mental health programs among Canadian working men, who were at high risk of a major depressive episode (MDE). Methods: A cross-sectional survey in 10 Canadian provinces was conducted between March and December 2015. Random digit dialing method was used through household landlines and cell phones to collect data from 511 working men who were at high risk of having an MDE and 330 working men who were at low risk of having an MDE. Results: High-risk men were more likely to endorse the importance of accessing health resources on the Internet than low-risk men (83.4% vs 75.0%, respectively; P=.01). Of the 17 different features assessed, the top three features most likely to be used by high-risk men were: information about improving sleep hygiene (61.3%), practice and exercise to help reduce symptoms of stress and depression (59.5%), and having access to quality information and resources about work stress issues (57.8%). Compared with men at low risk for MDE, men at high risk for MDE were much more likely to consider using almost every one of the different design features. Differences in preferences for the design features by age among men at high risk of MDE were found only for 3 of 17 features. Differences in preferences for design features between English- and French-speaking participants were found only for 4 out of the 17 features. Analysis of qualitative data revealed that privacy issues, perceived stigma, ease of navigation, personal relevance, and lack of personal interaction, time, and knowledge were identified as barriers to the use of e-mental health programs in working men who were at high risk of MDE. Conclusion: E-mental health programs may be a promising strategy for prevention of depression in working men. Development of e-mental health programs should consider men\u27s preferences and perceived barriers to enhance the acceptability of this approach

    Trajectories of self-rated health in people with diabetes: Associations with functioning in a prospective community sample

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    © 2013 Schmitz et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Self-rated health (SRH) is a single-item measure that is one of the most widely used measures of general health in population health research. Relatively little is known about changes and the trajectories of SRH in people with chronic medical conditions. The aims of the present study were to identify and describe longitudinal trajectories of self-rated health (SRH) status in people with diabetes. Methods: A prospective community study was carried out between 2008 and 2011. SRH was assessed at baseline and yearly at follow-ups (n=1288). Analysis was carried out through trajectory modeling. The trajectory groups were subsequently compared at 4 years follow-up with respect to functioning. Results: Four distinct trajectories of SRH were identified: 1) 72.2% of the participants were assigned to a persistently good SRH trajectory; 2) 10.1% were assigned to a persistently poor SRH trajectory; 3) mean SRH scores changed from good to poor for one group (7.3%); while 4) mean SRH scores changed from poor to medium/good for another group (10.4%). Those with a persistently poor perception of health status were at higher risk for poor functioning at 4 years follow-up than those whose SRH scores decreased from good to poor. Conclusions: SRH is an important predictor for poor functioning in diabetes, but the trajectory of SRH seems to be even more important. Health professionals should pay attention to not only SRH per se, but also changes in SRH over time.This work was supported by Operating Grant MOP-84574 from the Canadian Institutes of Health Research (CIHR). GG was supported by a doctoral fellowship from the CIHR. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Centre d’histoire sociale de l’Islam méditerranéen

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    Gianni Albergoni, assistant à l’Université de Paris-XIsabelle Rivoal, chargée de recherche au CNRSJean Schmitz, chargé de recherche à l’IRD Atelier d’anthropologie politique (Maghreb, Machrek, Afrique de l’Ouest) : factionnalisme et configurations sociales contemporaines Dans nombre de pays arabes et africains, ni l’État moderne, ni les violents soubresauts qui accompagnent, et compromettent, sa consolidation, ni les reclassements introduits dans la stratification sociale par les grands chang..

    Versatile Virus-Like Particle Carrier for Epitope Based Vaccines

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    BACKGROUND: Recombinant proteins and in particular single domains or peptides are often poorly immunogenic unless conjugated to a carrier protein. Virus-like-particles are a very efficient means to confer high immunogenicity to antigens. We report here the development of virus-like-particles (VLPs) derived from the RNA bacteriophage AP205 for epitope-based vaccines. METHODOLOGY/PRINCIPAL FINDINGS: Peptides of angiotensin II, S.typhi outer membrane protein (D2), CXCR4 receptor, HIV1 Nef, gonadotropin releasing hormone (GnRH), Influenza A M2-protein were fused to either N- or C-terminus of AP205 coat protein. The A205-peptide fusions assembled into VLPs, and peptides displayed on the VLP were highly immunogenic in mice. GnRH fused to the C-terminus of AP205 induced a strong antibody response that inhibited GnRH function in vivo. Exposure of the M2-protein peptide at the N-terminus of AP205 resulted in a strong M2-specific antibody response upon immunization, protecting 100% of mice from a lethal influenza infection. CONCLUSIONS/SIGNIFICANCE: AP205 VLPs are therefore a very efficient and new vaccine system, suitable for complex and long epitopes, of up to at least 55 amino acid residues in length. AP205 VLPs confer a high immunogenicity to displayed epitopes, as shown by inhibition of endogenous GnRH and protective immunity against influenza infection

    Classification of and risk factors for hematologic complications in a French national cohort of 102 patients with Shwachman-Diamond syndrome.

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    International audienceBACKGROUND: Patients with the Shwachman-Diamond syndrome often develop hematologic complications. No risk factors for these complications have so far been identified. The aim of this study was to classify the hematologic complications occurring in patients with Shwachman-Diamond syndrome and to investigate the risk factors for these complications. DESIGN AND METHODS: One hundred and two patients with Shwachman-Diamond syndrome, with a median follow-up of 11.6 years, were studied. Major hematologic complications were considered in the case of definitive severe cytopenia (i.e. anemia <7 g/dL or thrombocytopenia <20 × 10(9)/L), classified as malignant (myelodysplasia/leukemia) according to the 2008 World Health Organization classification or as non-malignant. RESULTS: Severe cytopenia was observed in 21 patients and classified as malignant severe cytopenia (n=9), non-malignant severe cytopenia (n=9) and malignant severe cytopenia preceded by non-malignant severe cytopenia (n=3). The 20-year cumulative risk of severe cytopenia was 24.3% (95% confidence interval: 15.3%-38.5%). Young age at first symptoms (<3 months) and low hematologic parameters both at diagnosis of the disease and during the follow-up were associated with severe hematologic complications (P<0.001). Fifteen novel SBDS mutations were identified. Genotype analysis showed no discernible prognostic value. CONCLUSIONS Patients with Shwachman-Diamond syndrome with very early symptoms or cytopenia at diagnosis (even mild anemia or thrombocytopenia) should be considered at a high risk of severe hematologic complications, malignant or non-malignant. Transient severe cytopenia or an indolent cytogenetic clone had no deleterious value

    NF-kappa B p65 serine 467 phosphorylation sensitizes mice to weight gain and TNF alpha-or diet-induced inflammation

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    The NF-kappa B family of transcription factors is essential for an effective immune response, but also controls cell metabolism, proliferation and apoptosis. Its broad relevance and the high connectivity to diverse signaling pathways require a tight control of NF-kappa B activity. To investigate the control of NF-kappa B activity by phosphorylation of the NF-kappa B p65 subunit, we generated a knock-in mouse model in which serine 467 (the mouse homolog of human p65 serine 468) was replaced with a non-phosphorylatable alanine (S467A). This substitution caused reduced p65 protein synthesis and diminished TNF alpha-induced expression of a selected group of NF-kappa B dependent genes. Intriguingly, high-fat fed S467A mice displayed increased locomotor activity and energy expenditure, which coincided with a reduced body weight gain. Although glucose metabolism or insulin sensitivity was not improved, diet-induced liver inflammation was diminished in S467A mice. Altogether, this study demonstrates that phosphorylation of p65 serine 467 augment NF-kappa B activity and exacerbates various deleterious effects of overnutrition in mice.</p

    Genome sequence of Desulfurella amilsii strain TR1 and comparative genomics of Desulfurellaceae family

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    The acidotolerant sulfur reducer Desulfurella amilsii was isolated from sediments of Tinto river, an extremely acidic environment. Its ability to grow in a broad range of pH and to tolerate certain heavy metals offers potential for metal recovery processes. Here we report its high-quality draft genome sequence and compare it to the available genome sequences of other members of Desulfurellaceae family: D. acetivorans, D. multipotens, Hippea maritima, H. alviniae, H. medeae and H. jasoniae. For most species, pairwise comparisons for average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) revealed ANI values from 67.5 to 80% and DDH values from 12.9 to 24.2%. D. acetivorans and D. multipotens, however, surpassed the estimated thresholds of species definition for both DDH (98.6%) and ANI (88.1%). Therefore, they should be merged to a single species. Comparative analysis of Desulfurellaceae genomes revealed different gene content for sulfur respiration between Desulfurella and Hippea species. Sulfur reductase is only encoded in D. amilsii, in which it is suggested to play a role in sulfur respiration, especially at low pH. Polysulfide reductase is only encoded in Hippea species; it is likely that this genus uses polysulfide as electron acceptor. Genes encoding thiosulfate reductase are present in all the genomes, but dissimilatory sulfite reductase is only present in Desulfurella species. Thus, thiosulfate respiration via sulfite is only likely in this genus. Although sulfur disproportionation occurs in Desulfurella species, the molecular mechanism behind this process is not yet understood, hampering a genome prediction. The metabolism of acetate in Desulfurella species can occur via the acetyl-CoA synthetase or via acetate kinase in combination with phosphate acetyltransferase, while in Hippea species, it might occur via the acetate kinase. Large differences in gene sets involved in resistance to acidic conditions were not detected among the genomes. Therefore, the regulation of those genes, or a mechanism not yet known, might be responsible for the unique ability of D. amilsii. This is the first report on comparative genomics of sulfur-reducing bacteria, which is valuable to give insight into this poorly understood metabolism, but of great potential for biotechnological purposes and of environmental significance.The authors thank CNPq (Conselho Nacional de Desenvolvimento Cientifiìco e Tecnoloìgico),organization of the Brazilian Government for supporting the doctoral study program for the development of Science and Technology. Research of IS-A and AM Stams is financed by ERC grant project 323009, and Gravitation grant project 024.002.002 fromTheNetherlands Ministry of Education, Culture and Science. Thanks to Bastian Hornung for the bioinformatics support and to Robert Smith for the English revision.info:eu-repo/semantics/publishedVersio
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