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International audience; Highlights: • We investigated multifunctionality and ecosystem services in agroecosystems. • 18 research questions, obstacles and solutions were identified. • Future research must integrate knowledge from different sectors and communities. • Biodiversity is a key factor to explore and incorporate into modelling approaches. • Promoting dialogue, standardization and data-sharing would enhance progress.Abstract:Agroecosystems are facing new challenges in the context of a growing and increasingly interconnected human population, and a paradigm shift is needed to successfully address the many complex questions that these challenges will generate. The transition to providing multiple services within an agroecosystem is a starting point for heightened multifunctionality, however, there is still hesitation among stakeholders about moving towards multi-service systems, largely because of the lack of knowledge linking productivity and multifunctionality. We reason that much of this reticence could be overcome through a better understanding of stakeholder requirements and innovative transdisciplinary research extended in the dimensions of time and space. We assembled experts in France to identify priority research questions for co-constructing projects with stakeholders. We identified 18 key questions, as well as the obstacles that hinder their resolution and propose potential solutions for tackling these obstacles. We illustrate that research into agroecosystem multifunctionality and service production must be a hugely collaborative effort and needs to integrate knowledge from different sectors and communities. Promoting dialogue, standardization and data-sharing would enhance transdisciplinary progress. Biodiversity is highlighted as a key factor to explore and incorporate into modelling approaches, but major advances must be made in the understanding of dynamic changes in the biodiversity-function-service nexus across landscapes. Resolving these research questions will allow us to translate knowledge into decision objectives, identify adaptation and tipping points in agroecosystems and develop social-ecological economic pathways that are adaptive over time.

International audience; IntroductionHIV epidemics in Western and Central Africa (WCA) remain concentrated among key populations, who are often unaware of their status. HIV self-testing (HIVST) and its secondary distribution among key populations, and their partners and relatives, could reduce gaps in diagnosis coverage.We aimed to document and understand secondary HIVST distribution practices by men who have sex with men (MSM), female sex workers (FSW), people who use drugs (PWUD); and the use of HIVST by their networks in Côte d’Ivoire, Mali, and Senegal.MethodsA qualitative study was conducted in 2021 involving (a) face-to-face interviews with MSM, FSW, and PWUD who received HIVST kits from peer educators (primary users) and (b) telephone interviews with people who received kits from primary contacts (secondary users). These individual interviews were audio-recorded, transcribed, and coded using Dedoose software. Thematic analysis was performed.ResultsA total of 89 participants, including 65 primary users and 24 secondary users were interviewed. Results showed that HIVST were effectively redistributed through peers and key populations networks. The main reported motivations for HIVST distribution included allowing others to access testing and protecting oneself by verifying the status of partners/clients. The main barrier to distribution was the fear of sexual partners’ reactions. Findings suggest that members of key populations raised awareness of HIVST and referred those in need of HIVST to peer educators. One FSW reported physical abuse.Secondary users generally completed HIVST within two days of receiving the kit. The test was used half the times in the physical presence of another person, partly for psychological support need. Users who reported a reactive test sought confirmatory testing and were linked to care. Some participants mentioned difficulties in collecting the biological sample (2 participants) and interpreting the result (4 participants).ConclusionThe redistribution of HIVST was common among key populations, with minor negative attitudes. Users encountered few difficulties using the kits. Reactive test cases were generally confirmed. These secondary distribution practices support the deployment of HIVST to key populations, their partners, and other relatives. In similar WCA countries, members of key populations can assist in the distribution of HIVST, contributing to closing HIV diagnosis gaps.

Un référentiel de compétences est une cartographie, un inventaire, qui répertorie l'ensemble des compétences attendues par un apprenant en termes de savoirs, de savoir-faire et de savoir-être à la fin d'une formation, et qui se distingue par ses usages normatif et explicatif. Depuis quelques années, le terme « référentiel » a envahi le discours de l'analyse, de l'action et de l'administration. Cette notion appartient à une famille de mots qui révèle une inflation normative dans le sens où leur « point commun est de rapporter une chose à autre chose, avec une certaine force conférée à l'acte » (Chauvière, 2006). Largement déployée dans le monde de la formation professionnelle et du travail social, le substantif « référentiel » s'est petit à petit développé dans l'enseignement supérieur avec l'application des recommandations européennes sur l'approche par compétences. Dans ce contexte de certification de compétences et de validation d'acquis d'expérience, l'adoption des référentiels de compétences a été motivée par une volonté de mettre en place un outil pour favoriser l'organisation des changements liés aux réformes (Postiaux, Bouillard & Romainville, 2010).

Motivated by the potential tension between coordination, which may require discriminating between identical agents, and social comparisons, which may call for small pay differentials, we analyze the optimal reward scheme in an organization involving agents with social preferences whose tasks are complementary. Although a tension exists between the effects of inequality aversion and altruism, there is always more reward inequality when agents are inequality-averse and altruistic than when they are purely self-interested. We then highlight how our results differ when agents are not altruistic but rather inequality-averse a la Fehr and Schmidt (1999)..

International audience; The burden of encephalitis and its associated viral etiology is poorly described in Africa. Moreover, neurological manifestations of COVID-19 are increasingly reported in many countries, but less so in Africa. Our prospective study aimed to characterize the main viral etiologies of patients hospitalized for encephalitis in two hospitals in Dakar. From January to December 2021, all adult patients that met the inclusion criteria for clinical infectious encephalitis were enrolled. Cerebrospinal fluids, blood, and nasopharyngeal swabs were taken and tested for 27 viruses. During the study period, 122 patients were enrolled. Viral etiology was confirmed or probable in 27 patients (22.1%), with SARS-CoV-2 (n = 8), HSV-1 (n = 7), HHV-7 (n = 5), and EBV (n = 4) being the most detected viruses. Age groups 40–49 was more likely to be positive for at least one virus with an odds ratio of 7.7. The mortality was high among infected patients, with 11 (41%) deaths notified during hospitalization. Interestingly, SARS-CoV-2 was the most prevalent virus in hospitalized patients presenting with encephalitis. Our results reveal the crucial need to establish a country-wide surveillance of encephalitis in Senegal to estimate the burden of this disease in our population and implement strategies to improve care and reduce mortality.

International audience; ObjectifsL’autodépistage du VIH (ADVIH), notamment la distribution dans les réseaux des personnes en contact avec des programmes de prévention (distribution secondaire), permet de rejoindre des personnes ayant faiblement accès au dépistage. Dans le cadre du projet ATLAS, une analyse des pratiques d’utilisation et de redistribution de l’ADVIH parmi les hommes qui ont des rapports sexuels avec des hommes (HSH), les travailleuses du sexe (TS), les usagers de drogues (UD) et leurs partenaires a été réalisée en Côte d’Ivoire, au Mali et au Sénégal.Matériels et MéthodesUne enquête qualitative a été conduite de janvier à juillet 2021. Des entretiens face-à-face et par téléphone ont été réalisés avec des utilisateurꞏtrices de l’ADVIH identifiéꞏes par (i) des pairsꞏes éducateurꞏtrices HSH, TS et UD ou (ii) via une enquête téléphonique anonyme.RésultatsAu total 80 personnes ont été interviewées (65 en face-à-face, 15 par téléphone). À la première utilisation, la majorité a réalisé l’ADVIH sans la présence d’unꞏe professionnelꞏle (2/3). Ils l’ont justifié par la facilité de réalisation de l’ADVIH et l’existence d’outils de supports. La majorité a redistribué des kits d’ADVIH à des partenaires sexuelsꞏles, pairꞏes/amiꞏes, clients pour les TS et d’autres types derelations sans difficulté majeure. Leur motivation commune était l’intérêt de la connaissance du statut VIH pour l’utilisateurꞏtrice finalꞏe. Cependant vis-à-vis des partenaires sexuelsꞏles et des clients des TS, il s’agissait surtout de s’informer du statut de ce/cette dernier-ère pour décider des mesures préventives à adopter. Les réactions des utilisateurꞏtrices secondaires étaient majoritairement positives parce que ce nouvel outil répondait à une attente liée au besoin de connaître leur statut VIH, certainꞏes n’ayant par ailleurs jamais fait de dépistage VIH. Quelques cas de refus ont été rencontrés, surtout de la part des clients occasionnels pour les TS. Un cas de violence physique de la part d’un client a été rapporté.Les raisons de non-proposition de l’ADVIH à son réseau variaient suivant les catégories de populations clés et les utilisateurꞏtrices secondaires. Les trois populations clés, surtout les UD, ont rapporté des craintes de réactions négatives de certainꞏes partenaires sexuelsꞏles. Les HSH et les UD en ont moins distribué à leurs pairꞏes/amiꞏes par rapport aux partenaires sexuelꞏles parce qu’ils/elles estimaient que ceux/celles-ci étaient dans les mêmes réseaux de distribution des kits d’ADVIH et en avaient donc déjà reçus. Chez les TS, l’ADVIH était moins souvent proposé aux clients et aux partenaires qui acceptaient l’utilisation du préservatif.ConclusionLes résultats montrent une bonne acceptation de l’ADVIH tant en distribution primaire que secondaire. La redistribution de l’ADVIH dans les réseaux des populations clés peut permettre d’accroitre l’accès au dépistage parmi les populations peu dépistées, sans répercussion négative pour les personnes qui le proposent.

Many current and future nuclear physics (NP) experiments across the United States have and are implementing micro-pattern gas detectors (MPGDs) to be used for tracking and PID purposes. MPGDs are capable of operating in high rate environments and providing excellent spatial resolution over a large-area with a low material budget. Summarized in this white paper is the role that MPGDs are playing in NP experiments and the R&D which is needed to meet the requirements of future NP experiments., contribution to Snowmass 2021

Ferritic-martensitic (F-M) steels with high chromium content are envisaged as structural material (hexagonal tubes) for future reactors due to their good thermal conductivity and their excellent swelling resistance under irradiation. However, one of the key issues that limit the operating window of these steels is the low temperature embrittlement (, Les aciers ferritiques-martensitiques (F/M) de haute teneur en chrome sont envisagés comme matériaux de structure (tubes hexagonaux) pour les réacteurs du futur grâce à leur bonne conductivité thermique et leur excellente résistance au gonflement sous irradiation. Cependant, l’un des problèmes clés qui limitent la fenêtre d’utilisation de ces aciers est la fragilisation à basse température (< 400 °C) avec durcissement. Cette fragilisation est causée par la formation d'amas riches en solutés NiSiPCr, des zones de type alpha’ (zones riches en Cr) et des boucles de dislocation. La compréhension des mécanismes à l’origine de la formation des amas d’impuretés et des zones de type ’ est nécessaire pour comprendre l’évolution de la microstructure sous irradiation. L’objectif de ce travail adossé au projet européen H2020/M4F (Multiscale Modeling for fusion and fission materials) est d’étudier les impacts des conditions d’irradiation sur l’évolution microstructurale des aciers ferritiques-martensitiques (F/M) en particulier les alliages modèles FeCr. La caractérisation des échantillons avant et après irradiation a été réalisée par sonde atomique tomographique. L’étude de l’influence de la dose d’irradiation et de la teneur en impuretés Ni, Si et P sur l’évolution de la microstructure des alliages Fe15CrX (X=Ni, Si, P ou NiSiP) montrent montre l’existence d’un effet de synergie des impuretés dans les alliages. Les résultats montrent que des amas de P se forment sur lesquels ségrégent les atomes de Ni et de Si et que les amas riches en solutés NiSiPCr et les boucles de dislocation sont de même nature. Les caractéristiques des zones de type alpha’ observées évoluent avec la dose. Les résultats de l’influence de l’énergie des ions sur la formation des amas d’impuretés et les zones de type alpha’ montrent que les amas et boucles de dislocation croissent avec l’augmentation de l’énergie des ions et que cette dernière n’a pas d’effet significatif sur la formation des zones de type ’. Les résultats de l’influence du taux de dommage sur la formation des amas d’impuretés dans l’alliage Fe15CrNiSiP ne montrent pas un effet significatif du taux de dommage. L’influence du taux de dommage sur la formation des zones de type ’ montre que la densité des zones riches en Cr augmente avec la diminution du flux. Le mode d’irradiation balayé ou défocalisé n’a aucun effet significatif sur la formation des zones de type alpha’, des amas et boucles riches en solutés NiSiPCr. La comparaison des résultats après irradiation aux ions et aux neutrons a permis de montrer qu’aucun effet significatif de la différence de taux de dommage entre les deux irradiations n’a été observé sur la formation des amas d’impuretés dans ces alliages. Les résultats montrent aussi qu’il est préférable d’utiliser une plus haute énergie des ions pour reproduire la microstructure observée après irradiation aux neutrons. La densité des amas riches en solutés NiSiPCr augmente avec la concentration en impuretés dans les alliages après irradiation aux neutrons. La précipitation alpha’ semble être retardée par la présence des impuretés Ni, Si et P dans les alliages. L’absence de précipitation ’ dans certains alliages peut être due à la dissolution balistique qui est aussi responsable du fait que les fluctuations de concentration sont moins développées sous irradiation aux ions dans l’alliage Fe15CrNiSiP.

Ce travail adhère à l'initiative de valorisation des végétaux conduite par la Grande Muraille Verte (GMV) pour faire face à la disparition des végétaux et des savoir-faire végétaux associés. L’objectif de cette étude est de déterminer la diversité végétale impliquée dans le traitement des pathologies dermatologiques au Ferlo (Sénégal) et d’évaluer l’activité antimicrobienne des plantes les plus utilisées. Pour ce faire, un guide d’entretien semi directif a été soumis aux enquêtés, afin de recueillir la diversité des plantes utilisées au Ferlo dans le traitement des dermatoses. Des tests de micro dilution ont permis d’évaluer la concentration minimale inhibitrice (CMI) d’extraits de Sept (7) plantes contre une souche fongique (Candida albicans) et une bactérienne (Staphyloccocus aureus). Vingt-huit (28) espèces réparties dans 26 genres et 14 familles ont été recensées comme impliquées dans le traitement des affections dermatologiques. L’écorce est la partie la plus exploitée, puis le latex, tandis que, la décoction, suivie de l’usage direct représentent les modes de préparation les plus fréquents. Treize (13) parmi les plantes proposées sont exclusivement utilisées contre les dermatoses, quatre (4) fréquemment exploitées, et onze (11) occasionnellement recommandées. Widou Thiengoli est la localité où l’on exploite le plus d’espèces suivi de Loughere Thiolly. Leptadenia lancifolia (Schumach.& Thonn.) Decne. Stereospermum kunthianum Cham. et Sterculia setigera Delile ont été identifiées comme actives contre Candida albicans avec respectivement des CMI de 1,5 mg/ml pour les deux premières et 0,755 mg/ml pour la troisième. Acacia seyal Delile, Sterculia setigera Delile et Anogeissus leiocarpa (DC) Guill. & Perr. ont détruit Staphylococcus aureus avec respectivement des CMI de 3 mg/ml pour les deux premières et 1,5 mg/ml pour la troisième.

International audience; Xylenes, classified as Volatil Organic Compounds, is a very harmful pollutant for human health that can be absorbed into the body via all exposures routes: inhalation, ingestion, or dermal. As defined by the US Environmental Protection Agency, the occupational exposure limi-tes are set to 100 ppm while the guidelines in non-occupational context are fixed to 50 ppm. For the concentration measurements in the at-mosphere, authorities commonly used sampling methods with post-exposure chemical titration or chromatography. A strong interest remains on the development of low cost, low power consumption and easy implemented microsensors able to deliver real-time indicative measurements in the ppm concentration range. Most of microsensors aimed to the quantification of xylene concentration in air imple-ment doped MOx [1,2], MOx nanocomposites [3,4] or Metallic Oxide Frameworks [5]. Despite their suitability for xylene detection into the ppmconcentration range, the main drawback remains the high required operating temperature (>250°C). During this lecture, the high potentialities ofacoustic microsensors with tetra-tert-butyl metallophthalocyanine as sensing materials for xylene monitoring will be highlighted. If neither the nature of the metallic layer used as an electrode on quartz, nor the nature of the central metal atom in the phthalocyanine macrocycle have no impact on the sensor responses, the sensing enhancement provided by butyl groups is established. Experimental results revealed that ttb-CuPc based QCM sensors are suitable for accurate measurements of xylene concentration from 50 to 500 ppm, without any hysteresis effect, at room temperature. The response and recovery times were assessed close to 3min, while the LOD to a few ppm, and a good repeatability is manifest. The cross-sensitivities were determined towards various VOCs and NO2, with higher responses obtained for xylenes (Fig.1). The influence of relative humidity of gas mixture on response was investigated and will be discussed

International audience; Ion irradiation is a powerful and affordable tool to rapidly test a wide range of irradiation conditions and make the link with the corresponding microstructural evolution. However, several issues of transferability of results from ion to neutron irradiation have been evidenced. This paper presents an atom probe investigation of the microstructural evolution of FeCr-NiSiP alloys with different contents of Cr and minor solutes under both ion and neutron irradiation at 300 °C. Minor solutes and Cr are known to form solute rich clusters (SRCs) and alpha' clusters in ferritic and martensitic FeCr alloys, which are one of the causes of hardening. The objective of this work is to highlight the differences and the commonalities between ion and neutron irradiations in these alloys. The use of two ion beam energies (8 MeV and 5 MeV) revealed that this parameter has an impact on the formation of SRCs. The SRCs present similar characteristics after 8 MeV Fe ion irradiation and neutron irradiation, despite the different dose rate, when Ni, Si and P are present. It is not the case for 5 MeV Fe ions, for which the SRCs were less developed. Influence of the concentration of minor elements has been evidenced, as well. The presence of Ni, Si and P has been shown to impact both the number density and the size of SRCs in Fe9Cr-NiSiP alloys and the onset of alpha' formation.

Implied volatility surface is of crucial interest for risk management and exotic option pricing models. Its construction is usually carried out in accordance with the arbitrage-free principle. This condition leads to shape restrictions on the option prices such as monotonicity with respect to maturities and convexity with respect to strike prices. In this paper, we propose a new arbitrage-free construction method that extends classical spline techniques by additionally allowing for quantification of uncertainty. The proposed method extends the constrained kriging techniques developed in [MB16] and [CMR16] to the context of volatility surface construction. Assuming a Gaussian process prior, the posterior price surface becomes a truncated Gaussian field given shape constraints and market observations. Prices of illiquid instruments can also be incorporated when considered as noisy observations. Starting from a suitable finite-dimensional approximation of the Gaussian process prior, the no-arbitrage condition on the entire input domain is characterized by a finite number of linear inequality constraints. We define the most likely response surface and the most-likely noise values as the solution of a quadratic optimization problem. We use Hamiltonian Monte Carlo technics to simulate the posterior truncated Gaussian surface and build pointwise confidence bands. The Gaussian process hyper-parameters are estimated using maximum likelihood. The method is illustrated on Euro Stoxx 50 option prices by building no-arbitrage volatility surfaces and their corresponding confidence bands.

Mortality surface is a function of age and year with the main characteristic of being increasing with respect to ages from a given age. One of the major challenges of its construction is to take this last specificity into account. In this paper, we propose to use constrained Kriging for such a construction. Our approach is based on the finite dimensional approximation of the Gaussian process. We first show the ability of Kriging to construct mortality surfaces and then compare its performance against classical Kriging models with trend functions such as those used in [LRZ18]. Our empirical study based on mortality data from three countries (France, Italy and Germany) showed the need to add a constraint of convexity in age and illustrated through an RMSE criterion that Kriging constraint provided better results in terms of out-of-sample forcasting.

International audience

International audience; APOL1 G1 and G2 alleles have been associated with kidney-related outcomes in people living with HIV (PLHIV) of Black African origin. No APOL1-related kidney risk data have yet been reported in PLHIV in West Africa, where high APOL1 allele frequencies have been observed. Methods: We collected clinical data from PLHIV followed in Burkina Faso (N = 413) and in the ANRS-12169/2LADY trial (Cameroon, Senegal, Burkina Faso, N = 369). APOL1 G1 and G2 risk variants were genotyped using TaqMan assays, and APOL1 high-risk (HR) genotype was defined by the carriage of 2 risk alleles. Results: In West Africa (Burkina Faso and Senegal), the G1 and G2 allele frequencies were 13.3% and 10.7%, respectively. In Cameroon (Central Africa), G1 and G2 frequencies were 8.7% and 8.9%, respectively. APOL1 HR prevalence was 4.9% in West Africa and 3.4% in Cameroon. We found no direct association between APOL1 HR and estimated glomerular filtration rate (eGFR) change over time. Nevertheless, among the 2LADY cohort participants, those with both APOL1 HR and high baseline viral load had a faster eGFR progression (β = −3.9[−7.7 to −0.1] ml/min per 1.73 m2 per year, P < 0.05) than those with low-risk (LR) genotype and low viral load. Conclusion: Overall, the APOL1 risk allele frequencies in PLHIV were higher in the West African countries than in Cameroon, but much lower than previously reported in some Nigeria ethnic groups, which strongly advocates for further investigation in the African continent. This study suggested that the virological status could modulate the APOL1 impact on kidney function, hence reinforcing the need for early therapeutic interventions.

Toxoplasma gondii is a eukaryotic parasite that forms latent cysts in the brain of immunocompetent individuals. The latent parasite infection of the immune-privileged central nervous system is linked to most complications. With no drug currently available to eliminate the latent cysts in the brain of infected hosts, the consequences of neurons' long-term infection are unknown. It has long been known that T. gondii specifically differentiates into a latent form (bradyzoite) in neurons, but how the infected neuron responds to the infection remains to be elucidated. We have established a new in vitro model resulting in the production of mature bradyzoite cysts in brain cells. Using dual, host and parasite RNA-seq, we characterized the dynamics of differentiation of the parasite, revealing the involvement of key pathways in this process. Moreover, we identified how the infected brain cells responded to the parasite infection revealing the drastic changes that take place. We showed that neuronal-specific pathways are strongly affected, with synapse signalling being particularly affected, especially glutamatergic synapse signalling. The establishment of this new in vitro model allows investigating both the dynamics of parasite differentiation and the specific response of neurons to long-term infection by this parasite.

International audience

The skin epidermis is continuously exposed to external aggressions, including environmental pollution. The cosmetic industry must be able to offer dedicated products to fight the effects of pollutants on the skin. We set up an experimental model that exposed skin explants maintained in culture to a pollutant mixture. This mixture P representing urban pollution was designed on the basis of the French organization ‘Air Parif’ database. A chamber, called Pollubox®, was built to allow a controlled nebulization of P on the cultured human skin explants. We investigated ultrastructural morphology by transmission electron microscopy of high pressure frozen skin explants. A global transcriptomic analysis indicated that the pollutant mixture was able to induce relevant xenobiotic and antioxidant responses. Modulated detoxifying genes were further investigated by laser micro-dissection coupled to qPCR, and immunochemistry. Both approaches showed that P exposure correlated with overexpression of detoxifying genes and provoked skin physiological alterations down to the stratum basale. The model developed herein might be an efficient tool to study the effects of pollutants on skin as well as a powerful testing method to evaluate the efficacy of cosmetic products against pollution.

International audience; We report on MRi-Share, a multi-modal brain MRI database acquired in a unique sample of 1870 young healthy adults, aged 18-35 years, while undergoing university-level education. MRi-Share contains structural (T1 and FLAIR), diffusion (multispectral), susceptibility-weighted (SWI), and resting-state functional imaging modalities. Here, we described the contents of these different neuroimaging datasets and the processing pipelines used to derive brain phenotypes, as well as how quality control was assessed. In addition, we present preliminary results on associations of some of these brain image-derived phenotypes at the whole brain level with both age and sex, in the subsample of 1722 individuals aged less than 26 years. We demonstrate that the post-adolescence period is characterized by changes in both structural and microstructural brain phenotypes. Grey matter cortical thickness, surface area and volume were found to decrease with age, while white matter volume shows increase. Diffusivity, either radial or axial, was found to robustly decrease with age whereas fractional anisotropy only slightly increased. As for the neurite orientation dispersion and densities, both were found to increase with age. The isotropic volume fraction also showed a slight increase with age. These preliminary findings emphasize the complexity of changes in brain structure and function occurring in this critical period at the interface of late maturation and early ageing.

Rift Valley fever (RVF) is endemic in northern Senegal, a Sahelian area characterized by a temporary pond network that drive both RVF mosquito population dynamics and nomadic herd movements. To investigate the mechanisms that explain RVF recurrent circulation, we modelled a realistic epidemiological system at the pond level integrating vector population dynamics, resident and nomadic ruminant herd population dynamics, and nomadic herd movements recorded in Younoufere area. To calibrate the model, serological surveys were performed in 2015–2016 on both resident and nomadic domestic herds in the same area. Mosquito population dynamics were obtained from a published model trained in the same region. Model comparison techniques were used to compare five different scenarios of virus introduction by nomadic herds associated or not with vertical transmission in Aedes vexans. Our serological results confirmed a long lasting RVF endemicity in resident herds (IgG seroprevalence rate of 15.3%, n = 222), and provided the first estimation of RVF IgG seroprevalence in nomadic herds in West Africa (12.4%, n = 660). Multivariate analysis of serological data suggested an amplification of the transmission cycle during the rainy season with a peak of circulation at the end of that season. The best scenario of virus introduction combined yearly introductions of RVFV from 2008 to 2015 (the study period) by nomadic herds, with a proportion of viraemic individuals predicted to be larger in animals arriving during the 2nd half of the rainy season (3.4%). This result is coherent with the IgM prevalence rate (4%) found in nomadic herds sampled during the 2nd half of the rainy season. Although the existence of a vertical transmission mechanism in Aedes cannot be ruled out, our model demonstrates that nomadic movements are sufficient to account for this endemic circulation in northern Senegal., Author summary Rift Valley fever (RVF) is one of the most important vector borne disease in Africa, seriously affecting the health of domestic ruminants and humans and leading to severe economic consequences. This disease is endemic in northern Senegal, a Sahelian area characterized by a temporary pond network that drive both RVF mosquito population dynamics and nomadic herd movements. Two non-exclusive mechanisms may support this endemicity: recurrent introductions of the virus by nomadic animals, and vertical transmission of the virus (i.e. from infected female mosquito to eggs) in local Aedes populations. The authors followed resident and nomadic domestic herds for 1 year. They used the data thus obtained to model a realistic epidemiological system at the pond level integrating vector population dynamics, resident and nomadic ruminant herd population dynamics. They found that the best scenario explaining RVF remanence combined yearly introductions of RVFV by nomadic herds, with a viraemic proportion predicted to be larger in animals arriving during the 2nd half of the rainy season, which is consistent with an amplification of virus circulation in the area during the rainy season. Although the existence of a vertical transmission mechanism in Aedes cannot be ruled out, their results demonstrates that nomadic movements are sufficient to account for this endemic circulation in northern Senegal.

Introduction: Diabetes is a leading cause of chronic kidney disease in the world. During the next decade, its burden is expected to increase in Africa with potential complications such as chronic kidney disease. However, epidemiology and risk factors of diabetic kidney disease are poorly described at population level. This study aimed to determine prevalence of diabetic kidney disease (DKD) in adult diabetics living in Saint-Louis, northern Senegal. Methods: A cross-sectional study including diabetic patients followed-up aged ≥18 years during a five-year period (2013-2018) in Saint-Louis. Clinical and biological parameters were collected during annual community-based mass screening. Diabetes was defined as fasting blood glucose ≥ 1.26 g/L confirmed by a second lab dosage. DKD was defined as persistence of albuminuria ≥ 30 mg/24h and/or estimated glomerular filtration rate (eGFR) 2. Data were analyzed with Stata 12.0. Results: We included a total of 1310 diabetic patients among whom 3.7% (95% CI = 1.4% - 9.8%) presented DKD. Their mean age was 46.2 ± 11.8 years and sex-ratio was 0.7. Micro-albuminuria and macro-albuminuria were present respectively in 59.2% and 18.4% of patients with DKD and half of them had a normal eGFR. Before the survey 89.8% of patients with DKD were not aware of their renal disease and only four of them had seen a nephrologist. After multivariate analysis, age (OR = 1.5; 95% CI = 1.1 - 3.4), duration of diabetes (OR = 1.2; 95% CI = 1.6 - 4.4) and hypertension (OR = 2.5; 95% CI = 1.4 - 4.6) were associated with the presence of DKD in diabetic patients while no significant association was not found with gender, blood glucose level, smoking and familial history. Conclusion: DKD is a frequent complication in diabetic adult population living in Saint-Louis. Early detection and management should be promoted in order to prevent progression to end-stage renal disease.

Soumission à Episciences; The reduction of the malaria prevalence rate in Senegal, in addition to all the efforts made in the treatment and prevention of malaria, also involves an Anti-larvae program (ALP). In order to make ALP more effective, data from mosquito breeding sites and the environment of these sites have been collected. All of the stored data must be processed to produce predictive information. In order to obtain reliable results from the predictions, the choice of algorithms is crucial. The expected result is to find algorithms with the highest prediction reliability and to determine which of the parameters collected by the sensors are decisive for the presence of larvae.; La réduction du taux de prévalence du paludisme au Sénégal, au-delà de tous les efforts engagés dans le traitement et la prévention du paludisme, passe aussi par la lutte anti-larvaire (LAL). Dans l’optique de rendre la LAL plus efficace, des données issues des gîtes de moustiques, de l’environnement de ses différents gîtes ont été recueillies. L’ensemble des données stockées doivent être soumises à des traitements afin d’en sortir des informations prédictives. Afin d’obtenir des résultats fiables issues des prédictions, le choix des algorithmes est déterminant. Le résultat espéré est de parvenir à trouver des algorithmes avec des taux de fiabilité en prédiction les plus élevés et de déterminer parmi les paramètres recueillis par les capteurs, ceux qui sont déterminants pour la présence de larves.

International audience; Aphanomyces euteiches is an oomycete pathogen that causes the pea root rot. We investigated the potential role of early belowground defense in pea (susceptible plant) and faba bean (tolerant plant) at three days after inoculation. Pea and faba bean were inoculated with A. euteiches zoospores. Root colonization was examined. Root exudates from pea and faba bean were harvested and their impact on A. euteiches development were assessed by using in vitro assays. A. euteiches root colonization and the influence of the oomycete inoculation on specialized metabolites patterns and arabinogalactan protein (AGP) concentration of root exudates were also determined. In faba bean root, A. euteiches colonization was very low as compared with that of pea. Whereas infected pea root exudates have a positive chemotaxis index (CI) on zoospores, faba bean exudate CI was negative suggesting a repellent effect. While furanoacetylenic compounds were only detected in faba bean exudates, AGP concentration was specifically increased in pea.This work showed that early in the course of infection, host susceptibility to A. euteiches is involved via a plant-species specific root exudation opening new perspectives in pea root rot disease management.

International audience; Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are the biological vectors of arboviruses of global importance in animal health. We characterized the physicochemical parameters that determine the density and composition of the main Culicoides species of veterinary interest in larval habitats of the Niayes region of Senegal. For this purpose, we combined larval and substrate sampling in the field in different habitat types with adult emergence and physicochemical analyses in the laboratory. Three major habitat types were identified, conditioning the predominant species of Culicoides and pH and the amount of organic matter were positively correlated with the abundance of larvae and emerging Culicoides, as opposed to salinity. The diversity of emerging Culicoides was positively correlated with pH while it was negatively correlated with salinity. Culicoides distinctipennis was the predominant species in the larval habitat group of freshwater lake edges. In the larval habitat group of pond and puddle edges, C. oxystoma and C. nivosus were predominant; both species were again most abundant in the larval habitat group of saltwater lake edges. These variabilities in physicochemical parameters support the distribution of different Culicoides species in different habitat groups. These results make it possible to implement effective, selective and environmental-friendly control measures but also to improve current models for estimating the abundance of adult vector populations at a local scale.

This thesis deals with various issues related to the quantitative management of financial risks. In the first part, we are interested in the models of default time in credit risk within the framework of the theory of enlargement of filtration. We propose models where the default time can coincide with some economic shock times. Our initial focus is the model of Jiao and Li (2018) in sovereign risk, where the default time coincides with predictable shock times. We extend this model in cases where shocks are not predictable by studying the characteristics of the default time. Second, we present the generalized Cox model which is an extension of the one of Lando (see Lando, 1998). We offer a wide range of examples for boiling our construction. The second part deals with the construction of volatility surfaces of financial assets under the condition of no-arbitrage opportunity using kriging methodologies (also called Gaussian process regression). These surfaces allow to estimate from the price of liquid options the value of financial products whose characteristics are non-standard and whose price is not observed on the market. The construction of such surfaces is an important step in some risk management processes. It also allows to evaluate non-liquid assets. Our approach is to learn the prices of European options through kriging while respecting the no-arbitrage conditions. These conditions are characterized by shape constraints on prices, namely monotonicity in the direction of maturities and convexity in the direction of strikes. Since these constraints correspond to a finite number of linear inequalities, we adopt a kriging technique under the constraints of linear inequalities. For this, we use the method developped by Maatouk and Bay (2016) which is based on the finite-dimensional approximation of the Gaussian process. The Monte Carlo Hamiltonien algorithm developed by Pakman and Paninski (2014) will be used to simulate the Gaussian coefficients. We propose a method for computing the Maximum a Posteriori (MAP) of the Gaussian process. We compare our method with those of constrained neural networks and SSVI.; Cette thèse traite différentes questions liées à la gestion quantitative des risques financiers. Nous nous intéressons, dans une première partie, aux modèles de temps de défaut en risque de crédit dans le cadre de la théorie de grossissement de filtrations. Nous proposons des modèles où le temps de défaut peut coïncider avec des instants de chocs économiques. Nous mettons l’accent, dans un premier temps, sur le modèle de Jiao et Li (2018) en risque souverain où le temps de dèfaut coïncide avec des temps de chocs prévisibles. Nous étendons ce modèle dans le cas où les chocs ne sont pas prévisibles en étudiant les caractéristiques du temps de défaut. Dans un second temps, nous présentons le modèle de Cox généralisé qui est une extention de celui de Lando (voir Lando, 1998). Nous proposons une large gamme d’exemples pour ullistrer notre construction. La seconde partie porte sur la construction de surfaces de volatilités des actifs financiers sous la condition d’absence d’opportunité d’arbitrage (AOA) en utilisant les méthodologies de krigeage (où la regression par processus Gaussien). Ces surfaces permettent par exemple d’estimer à partir du prix d’options liquides, la valeur des produits financiers dont les caractéristiques sont non-standard et dont le prix n’est pas observé sur le marché. La construction de telles surfaces est une étape importante dans certains processus de gestion des risques. Elle permet également de tarifer des actifs non-liquides. Notre approche consiste á mettre en œuvre l’apprentissage du krigeage sur les prix d’options européennes en respectant les conditions de non-arbitrage. Ces conditions sont caractérisées par des contraintes de forme sur les prix, à savoir la monotonicité dans la direction des maturités et la convexité dans la direction des strikes. Etant donné que ces contraintes correspondent à un nombre fini d’inégalités linéaires, nous adoptons une technique de krigeage sous contraintes d’inégalités linéaires. Nous utilisons, pour cela, la méthode d’eveloppée par Maatouk et Bay (2016) qui est basée sur l’approximation fini-dimensionnelle du processus Gaussien. L’algorithme de Monte Carlo Hamiltonien de Pakman et Paninski (2014) sera utilisé pour simuler les coefficients Gaussiens. Nous proposons une méthode de calcul du Maximum a Posteriori (MAP) du processus Gaussien. Nous comparons notre méthode avec celles des réseaux de neuronne contraints et des SSVI.

International audience; White spot areas depict geographic locations which are not covered by mobile network operators. In Senegal, the Sylvo-pastoral hosted by Ferlo's region has a prominent role according to livestock transhumance. Nevertheless, this region is roughly covered by white spot areas. The lack of cellular network infrastructure is a pitfall for vital information dissemination for agro-pastoralists. Therefore, this paper describes the deployment and testbed performance evaluation in rural and urban environment of a LoRa-based COWShED communication architecture. By leveraging a mesh-based prof-of-concept, tangible results are obtained and thus promote several applications which overcome white spot areas limitations such as stakeholders geolocation, transhumance management, milk collection, etc.

International audience; White spot areas depict geographic locations which are not covered by mobile network operators. In Senegal, the Sylvo-pastoral hosted by Ferlo's region has a prominent role according to livestock transhumance. Nevertheless, this region is roughly covered by white spot areas. The lack of cellular network infrastructure is a pitfall for vital information dissemination for agro-pastoralists. Therefore, this paper describes the deployment and testbed performance evaluation in rural and urban environment of a LoRa-based COWShED communication architecture. By leveraging a mesh-based prof-of-concept, tangible results are obtained and thus promote several applications which overcome white spot areas limitations such as stakeholders geolocation, transhumance management, milk collection, etc.

Access to health services is a concern around the world. Different strategies were developed, but Africa’s rate remains the lowest. This article aims to contribute to the population's access to healthcare, and to assess the determinants of the use of mutual health insurance by the population of the Ziguinchor region in Senegal. Methods: The study is transversal and descriptive, carried out from July to August 2018. Through the quota method we defined the number of patients to be interviewed. Thus, by a geographic stratification according to the departments and a second-degree stratification taking into account the staff of the different hospital departments, 392 patients were selected. Results: 73% at the Regional Hospital Center and 27% at the Regional Peace Hospital. Response rate: 97%, women 60% and men 40%. The enrollment for women (24%) is slightly higher than that for men (21%). Socio-economic factors. The rate of adherence is the highest of for patients with university level, followed by high school; income: the highest rate for patients with a monthly income between 200,000 and 500,000 FCFA, followed by patients with an income monthly between 100,000 and 200,000 FCFA. Factors linked to the provision of care: the rate of Mutual Health Insurance adherence follows distances from patients' homes. Concerning the relation to satisfaction, education, distance and information are more determining than adherence rate. Recommendations: 1) State: actions on education and distance; 2) Sensitizing the population on mutual health insurance; 3) Urging healthcare providers to reduce waiting times and respect schedules as well as appointments., South Eastern European Journal of Public Health (SEEJPH), Special Volume No. 2, 2021: Announcing the Hideyo Noguchi Africa Prize (1st edition)

International audience; The interactions between plant roots and the associated microbiota impact soil aggregation, water retention and plant nutrient availability. Thus, selection of plant genotypes that promote microbial species involved in rootadhering soil aggregation and rhizosheath formation could help improve yield sustainably. Here, we tested pearl millet genotypic variation in both root-adhering soil aggregation, microbiological and biochemical characteristic. Methods: A collection of 181 pearl millet inbred lines was phenotyped for their rhizosheath size, and thirteen contrasting genotypes were selected and grown under field conditions, and their root-adhering soil (RAS) was sampled. Microbial biomass, pH, mineral N content and six enzymatic activities involved in main nutrients cycles were analyzed, and metabarcoding of 16S rDNA and ITS were performed for bacterial and fungal diversity. Results: Enzymatic activities (chitinase, acid phosphomonoesterase, FDA-hydrolysis and β-glucosidase) were higher in RAS of larger rhizosheath lines than that of smaller rhizosheath one. Bacterial β-diversity showed a separation of the most contrasting lines in the principal coordinate analysis performed with the Bray-Curtis distance. Some bacteria from the Gaiellaceae and Sphingomonadaceae families and the Bradyrhizobium genus were associated with the large rhizosheath phenotype. Concerning the fungal community, we noticed a negative correlation between the specific richness and the rhizosheath size and Trichoderma genus was positively associated to the rhizosheath size. Conclusions: This study demonstrates that in pearl millet, rhizosheath size is related to soil nutrient dynamics and microbiota diversity. However, it also shows that other factors shape this trait and their relative importance must be determined.

International audience

Experimental cross sections for the $^4He(e,e'p)X$ reaction up to a missing momentum of 0.632 GeV/$c$ at $x_B=1.24$ and $Q^2$=2(GeV/$c$)$^2$ are reported. The data are compared to Relativistic Distorted Wave Impulse Approximation(RDWIA) calculations for $^4He(e,e'p)^3H$ channel. Significantly more events in the triton mass region are measured for $p_{m}$$>$0.45 GeV/$c$ than are predicted by the theoretical model, suggesting that the effects of initial-state multi-nucleon correlations are stronger than expected by the RDWIA model., Submitted to PRC

International audience; Our understanding of the viral communities associated to animals has not yet reached the level attained on the bacteriome. This situation is due to, among others, technical challenges in adapting metagenomics using high-throughput sequencing to the study of RNA viromes in animals. Although important developments have been achieved in most steps of viral metagenomics, there is yet a key step that has received little attention: the library preparation. This situation differs from bacteriome studies in which developments in library preparation have largely contributed to the democratisation of metagenomics. Here, we present a library preparation optimized for metagenomics of RNA viruses from insect vectors of viral diseases. The library design allows a simple PCR-based preparation, such as those routinely used in bacterial metabarcoding, that is adapted to shotgun sequencing as required in viral metagenomics. We first optimized our library preparation using mock viral communities and then validated a full metagenomic approach incorporating our preparation in two pilot studies with field-caught insect vectors; one including a comparison with a published metagenomic protocol. Our approach provided a fold increase in virus-like sequences compared to other studies, and nearly-full genomes from new virus species. Moreover, our results suggested conserved trends in virome composition within a population of a mosquito species. Finally, the sensitivity of our approach was compared to a commercial diagnostic PCR for the detection of an arbovirus in field-caught insect vectors. Our approach could facilitate studies on viral communities from animals and the democratization of metagenomics in community ecology of viruses.

Functional connectivity analyses of fMRI data have shown that the activity of the brain at rest is spatially organized into resting-state networks (RSNs). RSNs appear as groups of anatomically distant but functionally tightly connected brain regions. Inter-RSN intrinsic connectivity analyses may provide an optimal spatial level of integration to analyze the variability of the functional connectome. Here we propose a deep learning approach to enable the automated classification of individual independent-component (IC) decompositions into a set of predefined RSNs. Two databases were used in this work, BIL&GIN and MRi-Share, with 427 and 1811 participants, respectively. We trained a multilayer perceptron (MLP) to classify each IC as one of 45 RSNs, using the IC classification of 282 participants in BIL&GIN for training and a 5-dimensional parameter grid search for hyperparameter optimization. It reached an accuracy of 92%. Predictions for the remaining individuals in BIL&GIN were tested against the original classification and demonstrated good spatial overlap between the cortical RSNs. As a first application, we created an RSN atlas based on MRi-Share. This atlas defined a brain parcellation in 29 RSNs covering 96% of the gray matter. Second, we proposed an individualbased analysis of the subdivision of the default-mode network into 4 networks. Minimal overlap between RSNs was found except in the angular gyrus and potentially in the precuneus. We thus provide the community with an individual IC classifier that can be used to analyze one dataset or to statistically compare different datasets for RSN spatial definitions.

Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental programs at the next generation of lepton accelerators. In the context of the hadronic physics program at Jefferson Lab (JLab), positron beams are complementary, even essential, tools for a precise understanding of the electromagnetic structure of nucleons and nuclei, in both the elastic and deep-inelastic regimes. For instance, elastic scattering of polarized and unpolarized electrons and positrons from the nucleon enables a model independent determination of its electromagnetic form factors. Also, the deeply-virtual scattering of polarized and unpolarized electrons and positrons allows unambiguous separation of the different contributions to the cross section of the lepto-production of photons and of lepton-pairs, enabling an accurate determination of the nucleons and nuclei generalized parton distributions, and providing an access to the gravitational form factors. Furthermore, positron beams offer the possibility of alternative tests of the Standard Model of particle physics through the search of a dark photon, the precise measurement of electroweak couplings, and the investigation of charged lepton flavor violation. This document discusses the perspectives of an experimental program with high duty-cycle positron beams at JLab., Comment: 18 pages, 7 figures This version superseeds the previous version which scientific content was decomposed into several more elaborated articles. All of these articles will be collected in the EPJ A Topical Issue about "Positron beam and physics at Jefferson Lab (e+@Jlab)"

International audience; In 2005, the Government of Senegal initiated a project entitled "Projet de lutte contre les glossines dans les Niayes" (Tsetse control project in the Niayes) with the aim of creating a zone free of Glossina palpalis gambiensis in that area. The project received technical and financial support from the International Atomic Energy Agency (IAEA), the Food and Agriculture Organization of the United Nations (FAO), the Centre de Cooperation Internationale en Recherche Agronomique pour le Developpement (CIRAD) and the US Department of State through the Peaceful Uses Initiative (PUI). It was implemented in the context of the Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC) following a phased conditional approach (PCA) that entails implementation in distinct phases, in which support to the next phase is conditional upon completion of all (or at least the majority of) activities in the previous phase. In the case of the tsetse project in Senegal, the PCA consisted of 4 phases: (1) commitment of all stakeholders and training, (2) baseline data collection, feasibility studies and strategy development, (3) preparatory pre-operational activities and (4) operational activities. This paper provides an overview of the main activities that were carried out within each phase, with emphasis on the operational research carried out in phases 2 and 3, that was instrumental in guiding the project's decision-making. Activities of phase 2 focused on the collection of entomological, veterinary, socio-economic and environmental baseline data, and a population genetics study that proved the isolated character of the G. p. gambiensis population of the Niayes. These data enabled the tsetse-infested area to be delimited to 1000 km(2), the impact of animal trypanosomosis on the farmers' welfare to be quantified (annual benefits of 2 million Euro in the tsetse-infested zone), and the formulation of an area-wide integrated pest management (AW-IPM) strategy that included a sterile insect (SIT) component to eradicate the isolated tsetse populations from the Niayes. In view of the extreme fragmentation of the remaining favourable habitat of the Niayes and the high human population density (peri-urban area), which excluded the possibility of using the Sequential Aerosol Technique, the IPM strategy that was selected comprised the suppression of the tsetse population with insecticide-impregnated traps/targets and the use of "pour-on" for cattle, followed by the release of sterile males to eliminate the remaining relic pockets. During phase 3, the pre-operational phase, a series of activities were carried out that were needed to implement the operational phase. These included the establishment of a colony of tsetse originating from the target area in Senegal, competitiveness studies between the sterile flies and those from the target area, development of transport methods for long-distance shipments of sterile male pupae, competitiveness of the sterile male flies after release in the target area, development of aerial release methods (including a new chilled adult release system) and development of a Maxent-based distribution model to guide the suppression, sterile male releases and monitoring of the eradication campaign. To be able to properly manage the eradication campaign in different phases, the entire target area was divided into 3 operational blocks. This paper demonstrates how, during the operational phase, scientific principles continued to guide the implementation process. The results to date are encouraging, i.e. the deployment of 269 insecticide-impregnated Vavoua traps in favourable habitat of Block 1 reduced the apparent density of the G. p. gambiensis population significantly (from 0.42 (SD 0.39) to 0.04 (SD 0.11) flies/trap/day). This was followed by the aerial release of sterile males that reduced the apparent density to zero after six months of releases. The last wild fly was trapped on August 9, 2012 in Block 1. In Block 2, during the suppression, the apparent fly density dropped from 1.24 (SD 1.23) to 0.005 (SD 0.017) flies/trap/day. Sterile male releases were initiated in February 2014 and expanded to cover the entire Block 2 in January 2015. The apparent fly density has so far been reduced to < 0.001 fly per trap per day until the end of 2018 and releases are still ongoing. The results of the campaign are discussed with respect to the "adaptive management approach" used, which was deemed critical for the success of the campaign.

International audience

Objectifs : Le but de cette étude était de déterminer la composition phytochimique et la teneur en grandes classes chimiques des tiges les plus utilisées comme bâtonnets frotte-dents chez les peul de Widou Thiengoli au Nord Ferlo (Sénégal). Méthodes et résultats : Des entretiens ouverts semi structurés ont permis de recueillir les plantes les plus utilisées. L’indice de fidélité renseigne sur la convergence des usages quant à l’emploi des plantes comme bâtonnets frotte-dent comparé aux autres pratiques cosmétiques. L’étude de la composition phytochimique des tiges a ciblé 8 classes chimiques. Les tanins et les saponines sont très fréquents ; les terpénoïdes et les leuco-anthocyanines presque inexistants. Un dosage des flavonoïdes, alcaloïdes et polyphénols, réalisé chez des extraits aqueux, a porté sur 12 plantes. Les meilleures teneurs en polyphénols et alcaloïdes sont recueillies chez Anogeissus leiocarpa, et la meilleure en flavonoïdes chez Commiphora africana. Conclusion et applicabilité des résultats : Ces résultats permettent de sélectionner à travers la composition phytochimique des plantes, les espèces présentant de potentielles activités antimicrobiennes, car renfermant des composés phytochimique doués de fonctions germicides, au- delà de la fonction mécanique connue des bâtonnets dans l’élimination de la plaque dentaire. Mots clés : Bâtonnets frotte-dents, Dosage phytochimique, Ethnobotanique, Téssékéré, Ferlo Nord, 52 Sénégal Diatta et al., J. Appl. Biosci. 2021 Diversité et composition phytochimique des bâtonnets frotte-dents (cure-dents) proposés chez les Peul de la commune de Tessékéré (Ferlo Nord, Sénégal) 16268 Diversity and phytochemical composition of plants used as toothbrush sticks (toothpicks) by Fulani of Tessékéré commune (North Ferlo, Senegal) ABSTRACT Objectives: The aim of this study was to determine the phytochemical composition and the content of major chemical classes of the stems most used as tooth-brushing sticks among the Fulani of Widou Thiengoli in North Ferlo (Senegal). Methods and results: Open semi-structured interviews made it possible to collect data on the most used plants. The fidelity index provides information on the convergence of uses regarding the use of plants as toothbrushes compared to other cosmetic practices. The study of the phytochemical composition of the stems targeted 8 chemical classes. Tannins and saponins were very common; almost non- existent were the terpenoids and leuco-anthocyanins. An assay of flavonoids, alkaloids and polypnenols, in aqueous extracts, was carried out on 12 plants. The best contents of polyphenols and alkaloids were obtained from Anogeissus leiocarpa, and the best of flavonoids from Commiphora africana. Conclusion and applicability of the results: These results make it possible to select, through the phytochemical composition of plants, the species exhibiting potential antimicrobial activities, because they contain phytochemical compounds endowed with germicidal functions, beyond the known mechanical function of the rods in the plan removal of dental plaque. Keywords: Toothbrush sticks, Phytochemical determination, Ethnobotany, Téssékéré, North Ferlo, and Senegal.

International audience; Sub-Saharan Africa's hepatitis B virus (HBV) burden is primarily due to infection in infancy. However, data on chronic HBV infection prevalence and associated risk factors in children born post-HBV vaccination introduction are scarce. We estimated hepatitis B surface antigen (HBsAg) prevalence and risk factors in Senegalese children born during the HBV vaccination era. In 2018-2019, a community-based cross-sectional survey was conducted in Senegal among children born between 2004 and 2015 (ie after the three-dose HBV vaccine series was introduced (2004) but before the birth dose's introduction (2016)). HBsAg-positive children were identified using dried blood spots. A standardized questionnaire collected socioeconomic information. Data were age-sex weighted and calibrated to be representative of children living in the study area. Risk factors associated with HBsAg positivity were identified using negative binomial regression. Among 1,327 children, 17 were HBsAg-positive (prevalence = 1.23% (95% confidence interval [CI] 0.61-1.85)). Older age (adjusted incidence-rate ratio [aIRR] 1.31 per one-year increase, 95% CI 1.10-1.57), home vs healthcare facility delivery (aIRR 3.55, 95% CI 1.39-9.02), stitches (lifetime) (aIRR 4.79; 95% CI 1.84-12.39), tattoos (aIRR 8.97, 95% CI 1.01-79.11) and having an HBsAg-positive sibling with the same mother (aIRR 3.05, 95% CI 1.09-8.57) were all independently associated with HBsAg positivity. The low HBsAg prevalence highlights the success of the Senegalese HBV vaccination program. To further reduce HBV acquisition in children, high-risk groups, including pregnant women and siblings of HBsAg-positive individuals, must be screened. Vital HBV infection prevention measures include promoting delivery in healthcare facilities, and increasing awareness of prevention and control procedures.

International audience; exDNA is found in various organisms, including plants. However, plant exDNA has thus far received little attention related to its origin and role in the RET (root extracellular trap). In this study, we performed the first high-throughput genomic sequencing of plant exDNA from a Fabaceae with worldwide interest: soybean (Glycine max (L.) Merr.). The origin of this exDNA was first investigated in control condition, and the results show high-coverage on organelles (mitochondria/plastid) DNA relative to nuclear DNA, as well as a mix of coding and non-coding sequences. In the second part of this study, we investigated if exDNA release was modified during an elicitation with PEP-13 (a peptide elicitor from oomycete genus Phytophthora). Our results show that treatment of roots with PEP-13 does not affect the composition of exDNA.

We propose to use the High Momentum Spectrometer of Hall C combined with the Neutral Particle Spectrometer (NPS) to perform high precision measurements of the Deeply Virtual Compton Scattering (DVCS) cross section using a beam of positrons. The combination of measurements with oppositely charged incident beams is the only unambiguous way to disentangle the contribution of the DVCS $$^2$$ term in the photon electroproduction cross section from its interference with the Bethe-Heitler amplitude. This provides a stronger way to constrain the Generalized Parton Distributions of the nucleon. A wide range of kinematics accessible with an 11 GeV beam off an unpolarized proton target will be covered. The $$Q^2-$$ dependence of each contribution will be measured independently.

Cet article n'est publié dans aucune revue, j'aimerais qu'il soit corrigé puis publié par HAL; Cette étude vise à connaitre la diversité et les variations spatiotemporelles dans les communautés de macroalgues vivant le long de la côte Nord du Sénégal à deux échelles de temps (2 saisons froides et 2 saisons chaudes). Elle est réalisée par la méthode des transects et quadrats. L'inventaire a été effectué entre 2017 et 2019 dans 5 sites se trouvant sur ladite côte. Dans chaque site, 3 transects de 500 m distant chacun de 500 m l'un à l'autre et disposés perpendiculairement à la côte ont été prédéterminés à l'aide de Google Earth et du logiciel Arc Gis. Sur chaque transect, des points d'échantillonnages espacés de 50 m les uns des autres avec leurs coordonnés ont été préétablis. Sur chaque point d'échantillonnage, 3 quadrats ont été fixés puis les algues sont récoltées et décomptées. Au total, 12 espèces réparties dans 10 genres et 8 familles ont été identifiées dans tous les sites et saisons confondus. Une variation inter-sites et intersaisons des espèces a été notée avec une diversité plus importante en saison chaude 2017 et 2018 soit, respectivement 9 et 8 espèces. Les indices de Shannon calculés renseignent sur la faible diversité de la côte Nord du Sénégal. Meristotheca senegalensis, Laurencia obtusa, Dictyota ciliolata et Dictyopteris delicatula ont été rencontrées qu'en saisons chaudes tout au long de l'étude. En revanche, Caulerpa racemosa var. peltata a été observé en saisons froides. D'autres ont été observée dans toutes les saisons ; il s'agit du Caulacanthus ustulatus, Ceramium rubrum var. pacificum, Dictyota dichotoma et Bryopsis plumosa.

International audience

Estimating the epidemic potential of vector-borne diseases, along with the relative contribution of underlying mechanisms, is crucial for animal and human health worldwide. In West African Sahel, several outbreaks of Rift Valley fever (RVF) have occurred over the last decades, but uncertainty remains about the conditions necessary to trigger these outbreaks. We use the basic reproduction number (R0) as a measure of RVF epidemic potential in Northern Senegal, and map its value in two distinct ecosystems, namely the Ferlo and the Senegal river delta and valley. We consider three consecutive rainy seasons (July-November 2014, 2015 and 2016) and account for several vector and animal species. Namely, we parametrize our model with estimates of Aedes vexans arabiensis, Culex poicilipes, Culex tritaeniorhynchus, cattle, sheep and goats abundances. The impact of RVF virus introduction is assessed every week, in 4367 pixels of 3,5km2. The results of our analysis indicate that September was the month with highest epidemic potential in each study area, while at-risk locations varied between seasons. We show that decreased vector densities do not highly reduce R0 and that cattle immunity has a greater impact on reducing transmission than small ruminants immunity. The host preferences of vectors and the temperature-dependent time interval between their blood meals are crucial parameters needing further biological investigations.HighlightsSeptember is a period of high Rift Valley fever epidemic potential in northern Senegal regardless of the year, but exact locations where epidemics might start change between rainy seasons.Decreased vector densities during the rainy season did not highly reduce the epidemic potential of at-risk locations.High levels of immunity in cattle populations reduce more Rift Valley fever virus transmission than a high immunity in small ruminants in our study area. This aspect should be investigated further for targeted vaccination campaigns.Precise estimates of vector feeding preferences and the temperature-dependent lenght of their gonotrophic cycle are key to ensure a good detection of at-risk pixels.