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International audience; Glen Torridon (GT) is a recessive-trough feature on the northwestern slope of "Mt. Sharp" in Gale crater, Mars with the highest Fe-/Mg-phyllosilicates abundances detected by the Curiosity rover to date. Understanding the origin of these clay minerals and their relationship with diagenetic processes is critical for reconstructing the nature and habitability of past surface and subsurface environments in Gale crater. We aim to constrain the distribution and extent of diagenesis using compositional and morphological trends observed by visible-to-near infrared reflectance spectra in GT from Mastcam and ChemCam, supported by high-resolution images from the Mars Hand Lens Imager. Spectral features consistent with nontronite and fine-grained red hematite are ubiquitous throughout lower GT, and are strongest where diagenetic features are limited, suggesting that both were formed early, before burial. Diagenetic features increase in both abundance and diversity farther up-section, and we observe morphologic evidence for multiple episodes of diagenesis, with the edge of a diagenetic front partially preserved in the middle stratigraphic member, Knockfarril Hill. Near the contact between GT and the overlying Greenheugh pediment capping unit, we observe a lack of clay minerals with signatures consistent instead with coarse-grained gray hematite, likely formed through late-diagenetic alteration. We hypothesize that the sandstone-dominant Stimson formation acted as a conduit for diagenetic fluid flow into the area and that the clay-rich impermeable GT slowed the flow of those fluids, leading to enhanced alteration surrounding the clay-rich portions of GT, including within the nearby Vera Rubin ridge.

The SuperCam instrument, onboard the Perseverance rover (Mars 2020 mission) is designed to perform remote analysis on the Martian surface employing several spectroscopic techniques such as Laser Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman (TRR), Time-Resolved Fluorescence (TRF) and Visible and Infrared (VISIR) reflectance. In addition, SuperCam also acquires high-resolution images using a color remote micro-imager (RMI) as well as sounds with its microphone. SuperCam has three main subsystems, the Mast Unit (MU) where the laser for chemical analysis and collection optics are housed, the Body Unit (BU) where the different spectrometers are located inside the rover, and the SuperCam Calibration Target (SCCT) located on the rover's deck to facilitate calibration tests at similar ambient conditions as the analyzed samples. To perform adequate calibrations on Mars, the 22 mineral samples included in the complex SCCT assembly must have a very homogeneous distribution of major and minor elements. The analysis and verification of such homogeneity for the 5-6 replicates of the samples included in the SCCT has been the aim of this work. To verify the physic-chemical homogeneity of the calibration targets, micro Energy Dispersive X-ray Fluorescence (EDXRF) imaging was first used on the whole surface of the targets, then the relative abundances of the detected elements were computed on 20 randomly distributed areas of 100*100 mum. For those targets showing a positive Raman response, micro-Raman spectroscopy imaging was performed on the whole surface of the targets at a resolution of 100*100 mum. The %RSD values (percent of relative standard deviation of mean values) for the major elements measured with EDXRF were compared with similar values obtained by two independent LIBS set-ups at spot sizes of 300 mum in diameter. The statistical analysis showed which elements were homogeneously distributed in the 22 mineral targets of the SCCT, providing their uncertainty values for further calibration. Moreover, nine of the 22 targets showed a good Raman response and their mineral distributions were also studied. Those targets can be also used for calibration purposes of the Raman part of SuperCam using the wavenumbers of their main Raman bands proposed in this work. The authors would like to thank the Spanish Agency for Research, projects ESP2015-71965-REDT, ESP2017-87690-C3-1-R and RED2018-102600-T for funding as well as to local and regional institutions including the Basque Government, the University of the Basque Country, the Junta de Castilla y León, the University of Valladolid and the University of Malaga for their support. Support in the US was provided by NASA's Mars Exploration Program. Support in France was provided by CNES, CNRS, and local Universities. The Danish contribution was funded through support by the Carlsberg Foundation, grants CF16-0981 and CF17-0979. The team from the University of the Basque Country is very grateful to Sebastien Maussang and Victor Escobar from Renishaw for having faith in our work. The suggestions from T.R. Gabriel are gratefully acknowledged.

International audience

Before the Perseverance rover landing, the acoustic environment of Mars was unknown. Models predicted that: (1) atmospheric turbulence changes at centimetre scales or smaller at the point where molecular viscosity converts kinetic energy into heat

The adsorption technology based on low-cost adsorbents is of great interest for alternative sustainable abatement of toxic heavy metals from dilute industrial wastewaters. In this study, the perfor...

A recent randomized controlled trial, the WANECAM (West African Network for Clinical Trials of Antimalarial Drugs) trial, conducted at seven centers in West Africa, found that artemether-lumefantrine, artesunate-amodiaquine, pyronaridine-artesunate, and dihydroartemisinin-piperaquine all displayed good efficacy. However, artemether-lumefantrine was associated with a shorter interval between clinical episodes than the other regimens. In a further comparison of these therapies, we identified cases of persisting submicroscopic parasitemia by quantitative PCR (qPCR) at 72 h posttreatment among WANECAM participants from 5 sites in Mali and Burkina Faso, and we compared treatment outcomes for this group to those with complete parasite clearance by 72 h. Among 552 evaluable patients, 17.7% had qPCR-detectable parasitemia at 72 h during their first treatment episode. This proportion varied among sites, reflecting differences in malaria transmission intensity, but did not differ among pooled drug treatment groups. However, patients who received artemether-lumefantrine and were qPCR positive at 72 h were significantly more likely to have microscopically detectable recurrent Plasmodium falciparum parasitemia by day 42 than those receiving other regimens and experienced, on average, a shorter interval before the next clinical episode. Haplotypes of pfcrt and pfmdr1 were also evaluated in persisting parasites. These data identify a possible threat to the parasitological efficacy of artemether-lumefantrine in West Africa, over a decade since it was first introduced on a large scale.

The Curiosity rover investigated a topographic structure known as Vera Rubin ridge, associated with a hematite signature in orbital spectra. There, Curiosity encountered mudstones interpreted as lacustrine deposits, conformably overlying the 300 m‐thick underlying sedimentary rocks of the Murray formation at the base of Mount Sharp. While the presence of hematite (α‐Fe2O3) was confirmed in‐situ by both Mastcam and ChemCam spectral observations and by the CheMin instrument, neither ChemCam nor APXS observed any significant increase in FeOT (total iron oxide) abundances compared to the rest of the Murray formation. Instead, Curiosity discovered dark‐toned diagenetic features displaying anomalously high FeOT abundances, commonly observed in association with light‐toned Ca‐sulfate veins but also as crystal pseudomorphs in the host rock. These iron‐rich diagenetic features are predominantly observed in “grey” outcrops on the upper part of the ridge, which lack the telltale ferric signature of other Vera Rubin ridge outcrops. Their composition is consistent with anhydrous Fe‐oxide, as the enrichment in iron is not associated with enrichment in any other elements, nor with detections of volatiles. The lack of ferric absorption features in the ChemCam reflectance spectra and the hexagonal crystalline structure associated with dark‐toned crystals points toward coarse “grey” hematite. In addition, the host rock adjacent to these features appears bleached and show low‐FeOT content as well as depletion in Mn, indicating mobilization of these redox‐sensitive elements during diagenesis. Thus, groundwater fluid circulations could account for the remobilization of iron and recrystallization as crystalline hematite during diagenesis on Vera Rubin ridge.

Resume But de l’etude La possibilite de passer sa fin de vie chez soi est un enjeu de sante publique qui repond a la demande de la population et aux contraintes du systeme de sante. L’organisation de l’offre de soins et des acteurs infirmiers est donc centrale dans le developpement des soins palliatifs a domicile. L’objectif de cette etude etait de decrire la place des differents acteurs de soins infirmiers dans la prise en charge des situations palliatives avancees et terminales a domicile. Materiel et methodes Une enquete de pratique a ete realisee au moyen d’un questionnaire en ligne aupres des medecins generalistes installes en Gironde. Le reperage des situations palliatives etait realise avec le « Supportive & Palliative Care Indicators Tool » en version francaise (SPICT-FR™). Resultats En tout 89 medecins ont decrit la prise en charge de 607 patients en situations palliatives avancees et terminales en cours de suivi, et celle de 260 patients decedes a domicile au cours des 12 derniers mois a l’issue d’une pathologie en situation palliative. Les infirmiers liberaux assuraient, seuls, 64 % de l’ensemble des prises en charge en cours, et 56 % de celles le mois precedant le deces. Ils intervenaient egalement dans la majorite des situations ou les infirmiers des services d’hospitalisation a domicile et des services de soins infirmiers a domicile etaient presents. Conclusion Alors que la representation commune tend a considerer l’infirmier du service d’hospitalisation a domicile comme l’acteur majoritaire des situations palliatives avancees et terminales a domicile, cette enquete montre que les infirmiers liberaux ont une place preponderante dans ces situations. Le developpement des soins palliatifs a domicile et de la culture palliative passera par une meilleure reconnaissance et le soutien de ces acteurs.

Resume Introduction L’evolution de l’usage d’e-cigarette chez les usagers de cannabis et les polyconsommateurs d’alcool, tabac ou cannabis est peu decrite dans la litterature. Objectif principal Decrire l’evolution sur 12 mois de l’usage d’e-cigarette chez les usagers de cannabis et les polyconsommateurs. Methodes Etude observationnelle prospective de cohorte en medecine generale entre 2015 et 2016. Resultats Un total de 4,8 % des usagers de cannabis a l’inclusion sont restes ou devenus usagers actuels d’e-cigarette a la fin du suivi contre 4,5 % chez les non-usagers de cannabis, sans difference statistiquement significative. Un total de 5,1 % des polyconsommateurs a l’inclusion sont restes ou devenus usagers actuels d’e-cigarette a la fin du suivi contre 2,4 % chez les non-polyconsommateurs, sans difference statistiquement significative. Les usagers de cannabis et les polyconsommateurs declaraient plus d’experimentation d’e-cigarette par curiosite et sur proposition de quelqu’un, comparativement aux non-usagers de cannabis ou aux non-polyconsommateurs. Aucune association statistiquement significative n’a ete trouvee entre rester ou devenir usager actuel d’e-cigarette sur 12 mois et l’usage de cannabis ou la polyconsommation. Conclusion Les usagers de cannabis et les polyconsommateurs auraient tendance a experimenter davantage la cigarette electronique que les autres patients, sans pour autant se maintenir durablement dans son usage.

Contexte : Plusieurs études ont été menées en France sur la thèse d’exercice en médecine générale. Il s’agissait d’analyses régionales, réalisées par les départements de médecine générale. Une mise en commun des études régionales pourrait permettre d’identifier les perceptions du rôle de la thèse par ses acteurs et leurs divergences. Objectif : Explorer les rôles attribués par ses différents acteurs à la thèse d’exercice en médecine générale depuis 2004 en France. Méthode : Pour être éligibles, les documents devaient être écrits en anglais ou en français, aborder la thèse d’exercice en médecine générale et être parus entre 2004 et 2019. Etape 1 : Une revue systématique de la littérature a été effectuée sur Sudoc-Abès®, DocdocPro®, Babord+®, Medical Teacher® et Pédagogie Médicale®. Cette recherche systématique a été complétée d’une recherche manuelle. Étape 2 : Une analyse catégorielle thématique de contenu a été réalisée sur les do-cuments retenus, dans une approche hypothético-inductive. Le codage manuel a été effectué par deux chercheurs. Résultats : Etape 1 : Sur les 771 documents identifiés, la sélection sur titre et résumés en a conservé 104. Après lecture intégrale, il en a été retenu 67. Etape 2 : Trois rôles de la thèse étaient décrits : un travail académique imposé, un travail de recherche et un rite de passage. Six acteurs ont été identifiés : les étudiants, les directeurs de thèse, les jeunes généra-listes thésés, les départements de médecine générale, les commissions de thèse et les collèges de généralistes-enseignants. Les rôles perçus étaient partagés par les acteurs mais dans des proportions variables. Conclusion : Clarifier les rôles de la thèse d’exercice et tenir compte des attentes de ses acteurs paraît nécessaire pour faciliter leur convergence au cours du travail.

Key Points: • Mean K2O abundance in sedimentary rocks >5 times higher than that of the average Martian crust • Presence of alkali feldspars and K-phyllosilicates in basaltic sedimentary rocks along the traverse • The K-bearing minerals likely have a detrital origin

L’absence de recommandations medicales specifiques pour la prise en charge des mineurs isoles etrangers (MIE) entraine de grandes disparites selon les departements d’accueil. En etudiant leur etat de sante global nous souhaitons aider a promouvoir l’idee d’un guide de bonnes pratiques pour leur prise en charge sanitaire. Notre etude decrit des donnees obtenues a partir d’un bilan medical systematique propose aux MIE accueillis en Gironde entre janvier 2011 et decembre 2013. 235 MIE ont ete inclus, dont 143 ont des dossiers complets. Les pathologies les plus frequemment retrouvees, et/ou les plus graves, etaient les parasitoses digestives, les bilharzioses, les filarioses, l’hepatite B, la carence martiale, le deficit en G6PD et les caries dentaires. Sur le plan psychiatrique 45 % des MIE presentaient un tableau clinique compatible avec un etat de stress post traumatique. Les MIE cumulent les risques sanitaires des populations vulnerables que sont les adolescents et les refugies clandestins. Ils requierent donc une attention particuliere et adaptee des leur entree sur le territoire.

Resume Objectifs Evaluer l’evolution de la fonction renale apres nephrectomie partielle (NP) sur rein unique et rechercher des facteurs predictifs d’alteration de celle-ci. Materiel et methodes Quarante-cinq cas de nephrectomie partielle sur rein unique, operes en monocentrique entre 1988 a 2014, ont ete analyses retrospectivement. Les donnees clinicopathologiques pre-, per- et postoperatoires ont ete recueillies au sein de la base de donnees UroCCR. Nous avons evalue l’evolution postoperatoire precoce, a moyen et long terme du debit de filtration glomerulaire (DFG). Les facteurs predictifs d’alteration de la fonction renale et de recours a l’hemodialyse ont ete recherches en analyse multivariee. Resultats L’âge moyen des patients etait de 61 ans (± 10,8). Le DFG preoperatoire et la taille tumorale moyens etaient respectivement de 59,6 mL/min (± 18,7) et 3,9 cm (± 2,6). Un clampage vasculaire d’une duree mediane de 20 min (2–60) a ete realise dans 41 cas (91 %). Le suivi moyen etait de 66 mois (± 47). Les DFG moyens etaient respectivement de 46,4 mL/min, 50,3 mL/min et 53,1 mL/min a j5, 1 mois postoperatoire et a la date des dernieres nouvelles (DDN). Une diminution du DFG ≥ 20 % a ete constatee a j5 postoperatoire chez 20 patients (44,4 %) puis, a la DDN, chez 16 patients (35,5 %). Cinq patients (11 %) ont ete contraints a l’hemodialyse definitive (HD). La taille tumorale > 4 cm ( p = 0,006) et la duree operatoire ( p = 0,003) etaient les seuls facteurs predictifs d’une diminution du DFG a j5 postoperatoire. A 1 an de suivi, le RENAL ns ≥ 10 etait le seul facteur predictif de diminution du DFG ( p = 0,0007). Le DFG moyen preoperatoire etait significativement correle a la mise en dialyse definitive ( p = 0,023). Conclusion La NP permet de garantir l’autonomie renale a long terme de la majorite des patients sur rein unique. La taille et la complexite tumorales mais aussi le DFG preoperatoire apparaissent comme des facteurs determinants de l’evolution postoperatoire de la fonction renale. La prise en consideration de ces facteurs non modifiables devrait permettre une meilleure individualisation des patients a haut risque d’insuffisance renale postoperatoire. Niveau de preuve 5.

Within the Nutrition, Prevention, and Health Program for children and teenagers in Aquitaine, an experimental intervention was implemented in 2007-2008 in the middle and high schools in Aquitaine (southwest France). This intervention aimed to improve the eating habits of adolescents, combining actions to improve the food supply sold during recreational times (remove/limit fat and sugar products sold and promote the sale of fruits and bread) and health education actions to make adolescents aware of the concept of nutritional balance and steer their choice towards recommended products. The aim of this paper was to evaluate the impact of the intervention on the eating behavior of adolescents and the food supply sold during recreational times in middle and high schools in Aquitaine. A survey was conducted before and after the implementation of the intervention in seven middle and high schools that have implemented actions (intervention group) and eight middle and high schools that have not implemented actions (control group). In these schools, 1602 adolescents answered the survey before and 1050 after the intervention (samples were independent because of the anonymity of responses). The impact of the intervention on the dietary behavior of teenagers was modeled using logistic regression adjusted on potential confounding variables (sex, age, and educational status). In multivariate analyses, the intervention was associated with more frequent daily intake of breakfast (OR=2.63; 95% CI [1.89; 3.66]) and lower intake of morning snacks (OR=0.66; 95% CI [0.48; 0.90]), higher consumption of starchy foods (OR=1.77; 95% CI [1.30; 2.42]), bread at breakfast, morning snacks, and a light afternoon meal (OR=1.43; 95% CI [1.07; 1.90]), and the food supply sold at recreational times (OR=1.34 95% CI [1.01; 1.78]). These results show that the "Improving food supply in middle and high schools associated with educational support actions" project led to the sales of recommended foods during recreational times and improved students' eating behavior. These results encourage partners to pursue these actions in all volunteer middle and high schools.

Context Precariousness is increasing among all populations and especially among women. The access to healthcare is increasingly unequal upon the population and particularly in access to contraception methods or abortion according to their vulnerability level. Objective Our main object is to describe the socio-demographic specifications, the different steps involved in the healthcare itinerary to contraception and abortion, according to the level of social vulnerability for a woman population sample requesting an abortion. The secondary objects are to detect the existence of a difficult healthcare itinerary and to describe the exposure to risky situations or behaviors according to their vulnerability level. Method It is an observational cross-sectional survey to women having recourse to induced abortion in centers providing them, during 3 month in 2014, in the Aquitaine area. The validated tool to evaluate this situation in a psycho-social approach is the “EPICES score”. Results Our sample identifies 49% of women in a precariousness situation. These women are younger and more often less employed. They benefit less often from a regular gynecology follow-up, do not use contraception as often and resort to abortion more often. They relate more often risky behavior for the health, conflict with the partner and psychological, physical violence. Conclusion Special attention should be brought to all women in request of an abortion, for half of them are in a precarious situation and this physical might be a rare occasion of access to healthcare. Violence screening should be systematic and the choice of a long term birth control method should be encouraged.