62 research outputs found
Wood wasp inspired space and earth drill
In this chapter, we explain why the low gravity encountered on Mars or on the Moon and the low mass of the probes, landers and rovers that carry drilling devices limit classical drilling techniques. Novel boring solutions optimised in mass and power consumption are thus needed for space applications. Biologists have identified the wood wasp, an insect that is capable of "drilling" into wood to lay its eggs. A low mass and low power system, like an insect, capable of drilling into wood is of the highest interest for planetary drilling and terrestrial drilling alike. The general working principle of the wood wasp drill ("dual reciprocating drilling") will be exposed and the potential benefits of imitating the wood wasp for planetary drilling will be highlighted. Since the nature of wood is highly fibrous but the nature of extraterrestrial and terrestrial soils are not, it is necessary to adapt the wood wasp ovipositor to our target soils. A test bench to evaluate the influence of the different geometries and operational parameters was produced and is presented here. The dual reciprocating drilling experimental results obtained on this test bench are also highlighted. They should lead to a new and enhanced model and comprehension of dual-reciprocating-drilling
Drinking Patterns and Their Predictive Factors in CONTROL: a 12-Month Prospective Study in a Sample of Alcohol-Dependent Patients Initiating Treatment
Aims: To describe the drinking patterns and their baseline predictive factors during a 12-month period after an initial evaluation for alcohol treatment. Methods CONTROL is a single-center, prospective, observational study evaluating consecutive alcohol-dependent patients. Using a curve clustering methodology based on a polynomial regression mixture model, we identified three clusters of patients with dominant alcohol use patterns described as mostly abstainers, mostly moderate drinkers and mostly heavy drinkers. Multinomial logistic regression analysis was used to identify baseline factors (socio-demographic, alcohol dependence consequences and related factors) predictive of belonging to each drinking cluster. ResultsThe sample included 143 alcohol-dependent adults (63.6% males), mean age 44.6 ± 11.8 years. The clustering method identified 47 (32.9%) mostly abstainers, 56 (39.2%) mostly moderate drinkers and 40 (28.0%) mostly heavy drinkers. Multivariate analyses indicated that mild or severe depression at baseline predicted belonging to the mostly moderate drinkers cluster during follow-up (relative risk ratio (RRR) 2.42, CI [1.02-5.73, P = 0.045] P = 0.045), while living alone (RRR 2.78, CI [1.03-7.50], P = 0.044) and reporting more alcohol-related consequences (RRR 1.03, CI [1.01-1.05], P = 0.004) predicted belonging to the mostly heavy drinkers cluster during follow-up. Conclusion In this sample, the drinking patterns of alcohol-dependent patients were predicted by baseline factors, i.e. depression, living alone or alcohol-related consequences and findings that may inform clinicians about the likely drinking patterns of their alcohol-dependent patient over the year following the initial evaluation for alcohol treatmen
Regolith simulant preparation methods for hardware testing
International audienceTo qualify hardware for space flight, great care is taken to replicate the environment encountered in space. Emphasis is focused on presenting the hardware with the most extreme conditions it might encounter during its mission lifetime. The same care should be taken when regolith simulants are prepared to test space system performance. Indeed, the manner a granular material is prepared can have a very high inïŹuence on its mechanical properties and on the performance of the system interacting with it. Three regolith simulant preparation methods have been tested and are presented here (rain, pour, vibrate). They should enable researchers and hardware developers to test their prototypes in controlled and repeatable conditions. The pour and vibrate techniques are robust but only allow reaching a given relative density. The rain technique allows reaching a variety of relative densities but can be less robust if manually controlled
Epidemiological, virological and clinical characteristics of HBV infection in 223 HIV co-infected patients: a French multi-centre collaborative study
BACKGROUND: Chronic hepatitis B (CHB) is a clinical concern in human immunodeficiency virus (HIV)-infected individuals due to substantial prevalence, difficulties to treat, and severe liver disease outcome. A large nationwide cross-sectional multicentre analysis of HIV-HBV co-infected patients was designed to describe and identify parameters associated with virological and clinical outcome of CHB in HIV-infected individuals with detectable HBV viremia.
METHODS: A multicenter collaborative cross-sectional study was launched in 19 French University hospitals distributed through the country. From January to December 2007, HBV load, genotype, clinical and epidemiological characteristics of 223 HBV-HIV co-infected patients with an HBV replication over 1000 IU/mL were investigated.
RESULTS: Patients were mostly male (82%, mean age 42 years). Genotype distribution (A 52%; E 23.3%; D 16.1%) was linked to risk factors, geographic origin, and co-infection with other hepatitis viruses. This genotypic pattern highlights divergent contamination event timelines by HIV and HBV viruses. Most patients (74.7%) under antiretroviral treatment were receiving a drug with anti-HBV activity, including 47% receiving TDF. Genotypic lamivudine-resistance detected in 26% of the patients was linked to duration of lamivudine exposure, age, CD4 count and HIV load. Resistance to adefovir (rtA181T/V) was detected in 2.7% of patients. Advanced liver lesions were observed in 54% of cases and were associated with an older age and lower CD4 counts but not with viral load or genotype. Immune escape HBsAg variants were seldom detected.
CONCLUSIONS: Despite the detection of advanced liver lesions in most patients, few were not receiving anti-HBV drugs and for those treated with the most potent anti-HBV drugs, persistent replication suggested non-optimal adherence. Heterogeneity in HBV strains reflects epidemiological differences that may impact liver disease progression. These findings are strong arguments to further optimize clinical management and to promote vaccination in HIV-infected patients
ContrÎle de l'enherbement des parcelles de maïs menées en semis direct, Etat du Jalisco, Mexique
COL4A1/COL4A2 and inherited platelet disorder gene variants in fetuses showing intracranial hemorrhage.
Le plan de sauvegarde des Archives nationales : la gestion des ressources humaines
Indispensable dans tout Ă©tablissement culturel, un plan de sauvegarde ne saurait exister sans une Ă©quipe dâagents volontaires, formĂ©s et encadrĂ©s. Les Archives nationales ont mis en place depuis 2014 une stratĂ©gie pour recruter des volontaires disponibles pour intervenir, en cas de sinistre, en dehors des jours et heures habituels de travail. Ces volontaires sâengagent Ă suivre une formation spĂ©cifique. Celle-ci, ouverte largement Ă tous les agents des Archives nationales qui le souhaitent, comporte Ă la fois des aspects thĂ©oriques, sur lâorganisation mise en oeuvre aux Archives nationales, et des aspects pratiques, dans le cadre dâune mise en situation. Une attention particuliĂšre est portĂ©e Ă la formation des coordonnateurs et chefs dâĂ©quipe chargĂ©s dâencadrer les volontaires, qui ont Ă©tĂ© invitĂ©s Ă suivre une formation au «management en situation de crise » . LâefficacitĂ© du plan de sauvegarde repose pour beaucoup sur la cohĂ©sion de ces encadrants et sur leur capacitĂ© Ă se substituer, lorsquâune situation dâurgence survient, Ă la chaĂźne hiĂ©rarchique ordinaire des Archives nationales.Coste Patricia, Thibault Michel. Le plan de sauvegarde des Archives nationales : la gestion des ressources humaines. In: La Gazette des archives, n°254, 2019-2. Les Archives nationales, une refondation pour le XXIe siĂšcle. pp. 129-137
La science participative sur les traces du foxing aux Archives nationales
Le foxing biologique, câest-Ă -dire la prĂ©sence sur le papier de taches de couleur jaunĂątre Ă rousse, est un phĂ©nomĂšne courant. Si la prĂ©sence dans ces taches dâĂ©lĂ©ments fongiques est avĂ©rĂ©e, leur rĂŽle dans lâapparition du phĂ©nomĂšne reste trĂšs mal connu. Ă lâinitiative du centre de recherche sur la conservation, les Archives nationales ont sollicitĂ© leurs lecteurs pour participer Ă une enquĂȘte sur la prĂ©valence du foxing : pendant deux semaines, ils ont Ă©tĂ© invitĂ©s Ă rĂ©pondre, pour chaque article consultĂ©, Ă un questionnaire simple. De nombreux lecteurs se sont prĂȘtĂ©s au jeu et plus de mille trois cents questionnaires ont Ă©tĂ© remplis. Les dates des documents consultĂ©s confirment les centres dâintĂ©rĂȘt des lecteurs des Archives nationales, avec une sur-reprĂ©sentation des dĂ©cennies 1770 Ă 1830 et 1930 Ă 1970. De 1650 Ă 1850, la proportion de rĂ©ponses positives est dâune remarquable constance, entre 38 et 46 %. Ce taux baisse ensuite, pour sâeffondrer Ă partir de 1890. Ces rĂ©sultats conduisent Ă sâinterroger sur un lien Ă©ventuel entre les techniques de fabrication du papier et la prĂ©valence du foxing. Sans cet exercice de «science participative » , mener en deux semaines une enquĂȘte portant sur plus de mille articles aurait Ă©tĂ© impossible.Rakotonirainy Malalanirina Sylvia, Coste Patricia, Thibault Michel. La science participative sur les traces du foxing aux Archives nationales. In: La Gazette des archives, n°254, 2019-2. Les Archives nationales, une refondation pour le XXIe siĂšcle. pp. 309-320
Utility of S100B Serum Level for the Determination of Concussion in Male Rugby Players
International audienceThe incidence of concussion in professional direct-contact sports, particularly in rugby, has increased in recent years. To date, cognitive assessment is the most common means of determining whether a concussed player can return to the game. Serum S100B assay, an objective blood test known to be useful in brain injury management, may offer a novel additional approach to the management of concussed male rugby players
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