Evaluation of process causes and influences of residual stress on gear distortion

In the automotive industry, heat treatment of components is implicitly related to distortion. This phenomenon is particularly obvious in the case of gears because of their typical and precise geometry. Even if distortion can be anticipated to an extent by experience, it remains complex to comprehend. This paper presents an approach to estimate the distortion based on the idea of a distortion potential taking into account not only geometry but also the manufacturing process history. Then the idea is developed through simulation and experiments including annealing to understand the impact of residual stress on gear distortion in an industrial case study

A simple immersed-boundary method for solid-fluid interaction in constant- and stratified-density flows

The present work reports on the simulation of two- and three-dimensional constant- and stratifieddensity flows involving fixed or moving objects using an immersed-boundary method. The numerical approach is based on a simple immersed-boundary method in which no explicit Lagrangian marking of the immersed boundary is used. The solid object is defined by a continuous solid volume fraction which is updated thanks to the resolution of the Newton’s equations of motion for the immersed object. As shown on several test cases, this algorithm allows the flow field near the solid boundary to be correctly captured even though the numerical thickness of the transition region separating the fluid from the object is within three computational cells approximately. The full set of governing equations is then used to investigate some fundamental aspects of solid–fluid interaction, including fixed and moving objects in constant and stratified-density flows. In particular, the method is shown to accurately reproduce the steady-streaming patterns observed in the near-region of an oscillating sphere, as well as the so-called Saint Adrew’s cross in the far-field when the sphere oscillates in a rotating stratified fluid. The sedimentation of a particle in a stratified ambient is investigated for particle Reynolds numbers up to Oð103Þ and the effect of stratification and density ratio is addressed. While the present paper only consider fluid–solid interaction for a single object, the present approach can be straightforwardly extended to the case of multiple objects of arbitrary shape moving in a stratified-density flow

Evaluation of process causes and influences of residual stress on gear distortion

In the automotive industry, heat treatment of components is implicitly related to distortion. This phenomenon is particularly obvious in the case of gears because of their typical and precise geometry. Even if distortion can be anticipated to an extent by experience, it remains complex to comprehend. This paper presents an approach to estimate the distortion based on the idea of a distortion potential taking into account not only geometry but also the manufacturing process history. Then the idea is developed through simulation and experiments including annealing to understand the impact of residual stress on gear distortion in an industrial case study

Viromics on honey-baited FTA cards as a new tool for the detection of circulating viruses in mosquitoes

Worldwide, emerging and re-emerging infectious diseases (EIDs) are a major burden on public and animal health. Arthropod vectors, with mosquitoes being the main contributors of global disease, transmit more than 70% of the recognized EIDs. To assess new alternatives for arthropod-borne viral diseases surveillance, and for the detection of new viruses, honey-baited Flinders Technology Associates (FTA) cards were used as sugar bait in mosquito traps during entomological surveys at the Llobregat River Delta (Catalonia, Spain). Next generation sequencing (NGS) metagenomics analysis was applied on honey-baited FTA cards, which had been exposed to field-captured mosquitoes to characterize their associated virome. Arthropod- and plant-infecting viruses governed the virome profile on FTA cards. Twelve near-complete viral genomes were successfully obtained, suggesting good quality preservation of viral RNAs. Mosquito pools linked to the FTA cards were screened for the detection of mosquito-associated viruses by specific RT-PCRs to confirm the presence of these viruses. The circulation of viruses related to Alphamesonivirus, Quaranjavirus and unclassified Bunyavirales was detected in mosquitoes, and phylogenetic analyses revealed their similarities to viruses previously reported in other continents. To the best our knowledge, our findings constitute the first distribution record of these viruses in European mosquitoes and the first hint of insect-specific viruses in mosquitoes’ saliva in field conditions, demonstrating the feasibility of this approach to monitor the transmissible fraction of the mosquitoes’ virome. In conclusion, this pilot viromics study on honey-baited FTA cards was shown to be a valid approach for the detection of viruses circulating in mosquitoes, thereby setting up an alternative tool for arbovirus surveillance and control programs.info:eu-repo/semantics/publishedVersio

Skeletal muscle characteristics are preserved in hTERT/cdk4 human myogenic cell lines

Background: hTERT/cdk4 immortalized myogenic human cell lines represent an important tool for skeletal muscle research, being used as therapeutically pertinent models of various neuromuscular disorders and in numerous fundamental studies of muscle cell function. However, the cell cycle is linked to other cellular processes such as integrin regulation, the PI3K/Akt pathway, and microtubule stability, raising the question as to whether genetic modification related to the cell cycle results in secondary effects that could undermine the validity of these cell models.Results: Here we subjected five healthy and disease muscle cell isolates to transcriptomic analysis, comparing immortalized lines with their parent primary populations in both differentiated and undifferentiated states, and testing their myogenic character by comparison with non-myogenic (CD56-negative) cells. Principal component analysis of global gene expression showed tight clustering of immortalized myoblasts to their parent primary populations, with clean separation from the non-myogenic reference. Comparison was made to publicly available transcriptomic data from studies of muscle human pathology, cell, and animal models, including to derive a consensus set of genes previously shown to have altered regulation during myoblast differentiation. Hierarchical clustering of samples based on gene expression of this consensus set showed that immortalized lines retained the myogenic expression patterns of their parent primary populations. Of 2784 canonical pathways and gene ontology terms tested by gene set enrichment analysis, none were significantly enriched in immortalized compared to primary cell populations. We observed, at the whole transcriptome level, a strong signature of cell cycle shutdown associated with senescence in one primary myoblast population, whereas its immortalized clone was protected.Conclusions: Immortalization had no observed effect on the myogenic cascade or on any other cellular processes, and it was protective against the systems level effects of senescence that are observed at higher division counts of primary cells

Medical interns' knowledge and training regarding urethral catheter insertion and insertion-related urethral injury in male patients

<p>Abstract</p> <p>Background</p> <p>Improper catheterization can lead to urethral injury. Yet research from four continents suggests training of junior doctors in catheterization is insufficient. European research suggests a majority of catheterization related morbidities occur when the procedure is performed by interns.</p> <p>Methods</p> <p>To assess the knowledge and practices of medical interns relating to urethral catheterization and iatrogenic urethral injury secondary to traumatic catheter insertion, a questionnaire survey was conducted of all first year medical interns at a tertiary national university hospital in the Philippines. The questionnaire contained 17 items covering 4 areas: methods of training in catheterization and level of experience; perceived adequacy of training; theoretical knowledge of catheterization; the mechanisms of catheter-related urethral injury.</p> <p>Results</p> <p>225/240 interns (94%) completed the survey (130 (57.8%) female). 125 (55.6%) responded that they had adequate theoretical training and 150 (66.7%) adequate practical training. All had performed more than 10 catheterizations and 204 (90%) were supervised when they first performed catheterization. Despite relatively high levels of experience and confidence, deficits were identified in detailed knowledge of correct catheterization procedures and of risks associated with urethral injury.</p> <p>Conclusions</p> <p>More thorough training of incoming medical interns in urinary catheterization may help to reduce the risk of complications and injury. Training should be universal and thought given to its timing within the curriculum. Training should include step by step instruction in the process, emphasis on history taking and awareness of factors associated with increased risk of urethral injury.</p

Mortalité et cyclones en Guadeloupe (Antilles françaises)

Cet article pose les bases méthodologiques d’un catalogue historique des évènements hydro-météorologiques significatifs et mortels qui ont frappé l’archipel de Guadeloupe et les îles du Nord (Saint-Martin et Saint-Barthélemy) depuis 1635. Pour la période récente, post 1950, il est doublé d’un Système d’Information Géographique permettant de localiser et de renseigner chaque victime avec son profil, son comportement, les circonstances et causes du décès. Outre l’apport de bilans humains consolidés, ce nouveau référentiel géo-historique permet d’analyser l’évolution de la mortalité au cours du temps en lien avec les principaux facteurs de vulnérabilité. On peut en tirer un certain nombre d’enseignements utiles pour guider la prévention des risques en Guadeloupe.This paper lays the methodological basis for a historical catalogue of significant and deadly hydro-meteorological events that have occurred in the Guadeloupe archipelago and the northern islands since 1635. For the recent period, post 1950, it is supplemented by a Geographical Information System used to locate and inform each victim with his profile, his behavior, the circumstances and causes of death. In addition to the contribution of consolidated human death tolls, this new geo-historical framework makes it possible to analyze the evolution of mortality over time in relation to the main factors of vulnerability. A number of useful lessons can be drawn from this to guide risk prevention in Guadeloupe

Accurate fundamental parameters for 23 bright solar-type stars

We combine results from interferometry, asteroseismology and spectroscopy to determine accurate fundamental parameters of 23 bright solar-type stars, from spectral type F5 to K2 and luminosity classes III to V. For some stars we can use direct techniques to determine the mass, radius, luminosity and effective temperature, and we compare with indirect methods that rely on photometric calibrations or spectroscopic analyses. We use the asteroseismic information available in the literature to infer an indirect mass with an accuracy of 4-15 percent. From indirect methods we determine luminosity and radius to 3 percent. For Teff we find a slight offset of -40+-20 K between the spectroscopic method and the direct method, meaning the spectroscopic temperatures are too high. From the spectroscopic analysis we determine the detailed chemical composition for 13 elements, including Li, C and O. We find no significant offset between the spectroscopic surface gravity and the value from combining asteroseismology with radius estimates. From the spectroscopy we also determine vsini and we present a new calibration of macro- and microturbulence. From the comparison between the results from the direct and spectroscopic methods we claim that we can determine Teff, log g, and [Fe/H] with absolute accuracies of 80 K, 0.08 dex, and 0.07 dex. The indirect methods are important to obtain reliable estimates of the fundamental parameters of relatively faint stars when interferometry cannot be used. Our study is the first to compare direct and indirect methods for a large sample of stars, and we conclude that indirect methods are valid, although slight corrections may be needed.Comment: Accepted by MNRAS. Abstract abridge

Immortalized pathological human myoblasts: towards a universal tool for the study of neuromuscular disorders

<p>Abstract</p> <p>Background</p> <p>Investigations into both the pathophysiology and therapeutic targets in muscle dystrophies have been hampered by the limited proliferative capacity of human myoblasts. Isolation of reliable and stable immortalized cell lines from patient biopsies is a powerful tool for investigating pathological mechanisms, including those associated with muscle aging, and for developing innovative gene-based, cell-based or pharmacological biotherapies.</p> <p>Methods</p> <p>Using transduction with both telomerase-expressing and cyclin-dependent kinase 4-expressing vectors, we were able to generate a battery of immortalized human muscle stem-cell lines from patients with various neuromuscular disorders.</p> <p>Results</p> <p>The immortalized human cell lines from patients with Duchenne muscular dystrophy, facioscapulohumeral muscular dystrophy, oculopharyngeal muscular dystrophy, congenital muscular dystrophy, and limb-girdle muscular dystrophy type 2B had greatly increased proliferative capacity, and maintained their potential to differentiate both <it>in vitro </it>and <it>in vivo </it>after transplantation into regenerating muscle of immunodeficient mice.</p> <p>Conclusions</p> <p>Dystrophic cellular models are required as a supplement to animal models to assess cellular mechanisms, such as signaling defects, or to perform high-throughput screening for therapeutic molecules. These investigations have been conducted for many years on cells derived from animals, and would greatly benefit from having human cell models with prolonged proliferative capacity. Furthermore, the possibility to assess <it>in vivo </it>the regenerative capacity of these cells extends their potential use. The innovative cellular tools derived from several different neuromuscular diseases as described in this report will allow investigation of the pathophysiology of these disorders and assessment of new therapeutic strategies.</p

Nuclear Importation of Mariner Transposases among Eukaryotes: Motif Requirements and Homo-Protein Interactions

Mariner-like elements (MLEs) are widespread transposable elements in animal genomes. They have been divided into at least five sub-families with differing host ranges. We investigated whether the ability of transposases encoded by Mos1, Himar1 and Mcmar1 to be actively imported into nuclei varies between host belonging to different eukaryotic taxa. Our findings demonstrate that nuclear importation could restrict the host range of some MLEs in certain eukaryotic lineages, depending on their expression level. We then focused on the nuclear localization signal (NLS) in these proteins, and showed that the first 175 N-terminal residues in the three transposases were required for nuclear importation. We found that two components are involved in the nuclear importation of the Mos1 transposase: an SV40 NLS-like motif (position: aa 168 to 174), and a dimerization sub-domain located within the first 80 residues. Sequence analyses revealed that the dimerization moiety is conserved among MLE transposases, but the Himar1 and Mcmar1 transposases do not contain any conserved NLS motif. This suggests that other NLS-like motifs must intervene in these proteins. Finally, we showed that the over-expression of the Mos1 transposase prevents its nuclear importation in HeLa cells, due to the assembly of transposase aggregates in the cytoplasm