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Adoption of HIV preexposure prophylaxis (PrEP) among female sex workers (FSWs) in Côte d’Ivoire: complex trajectories and early adopters
No full textInternational audienceBACKGROUND: The ANRS 12381 PRINCESSE project (11/2019-06/2023) enrolled 489 FSWs and implemented community-based sexual and reproductive health care, including PrEP, delivered through mobile clinics at prostitution sites in the San Pedro region. This presentation aims to describe PrEP trajectories and the factors associated with its use, focusing on “early adopters”.METHODS: This analysis included 400 FSWs eligible for PrEP (HIV-negative, HBsAg-negative) enrolled up to December 2022 (>6 months of follow-up). Clinical records were analyzed to describe PrEP cascade, follow-up, and PrEP trajectories. A multivariable logistic regression identified factors associated with PrEP early adopters.RESULTS: Although 98% of eligible FSWs were interested in PrEP, only 62% initiated PrEP, and 39% renewed it at least once.Follow-up was very short (12 months with a gap of 6 months between two visits) for 31%, and regular (>12 months with no gap) for 6%.PrEP initiation was high among FSWs with regular (96%), seasonal (83%), or short (80%) follow-up, vs. 39% for those with very short follow-up. Among those who initiated, only 88% (regular), 70% (seasonal), 74% (short), and 35% (very short) renewed PrEP.Among 148 FSWs with regular/seasonal follow-up, four PrEP trajectories were identified (cf. figure showing individual trajectories): 15% “never initiated” PrEP, 39% “initiated and were later not interested anymore”, 18% “re-initiated after non-interest”, and 28% “initiated and never expressed non-interest”, the last two groups being considered as “early adopters”. Factors associated with early PrEP adoption included the usual price of intercourse with clients <1500 FCFA (aOR=2.4 [1.2-4.8]) and working in brothels (aOR=3.2 [1.6-6.6]).Figures presenting individual PrEP trajectories of FSWs enrolled in the PRINCESSE projectCONCLUSIONS: In PRINCESSE, loss-to-follow-up and seasonality of risks limited PrEP adoption. FSWs who were more precarious and less mobile became early adopters of this new prevention tool and could serve as potential ambassadors for promoting its uptake
Suppressing shear band instability in crystal/glass nanolaminates with high strength and plasticity
No full textInternational audienceCrystal/glass nanolaminates (NLs) present mutually exclusive mechanical properties by combining the strength of the glass phase with the ductility of the crystalline phase. For instance, optimizing the layers thickness of Cu/CuZr NLs suppresses shear band instability and promotes co-deformation, achieving a strength of 2.5 GPa and 40% plasticity in compression [1,2]. However, the role of deformation mechanisms and interface interactions in suppressing shear band instability remains incompletely understood. Additionally, BCC/glass NLs remain largely unexplored despite their proven potential to present high strength and ductility [3].Here, we synthesized 2 µm-thick Fe/Zr40Cu60 (crystal/glass) NLs by magnetron co-sputtering. We varied the Zr40Cu60 thickness (10-90 nm), keeping the Fe at 10 nm, to investigate the size-dependent deformation-mode transition. In a second approach, we varied the bilayer period between 20-80 nm at equal volume fractions, tuning the interface density. This study aims to establish architectural and interface engineering strategies to suppress shear band instability.The hardness of the Fe/Zr40Cu60 NLs exceeds individual layer values, reaching 9.6 GPa for the 10/10 nm NLs due to the sharp interfaces blocking the shear band. Micropillar compression tests reveal that thicker Zr40Cu60 layers (90 nm) lead to localized shear bands, whereas thinner layers show delayed shear band instability. Combining interface and architecture effects, 20/20 nm exhibits an exceptional 45% compressive plasticity and yield strength of 1.96 GPa due to effective shear band instability suppression.Overall, our findings provide insights into the nanoengineering of crystal/glass NLs interfaces and architectures to enhance their mechanical properties effectively.[1] J. Y. Kim et al., Adv Funct Mater, vol. 21, no. 23, Dec. 2011. [2] W. Guo et al., Acta Mater, vol. 80, 2014. [3] F. Qin et al., Mater. Sci. Eng. A, vol. 891, 2024
The Effect of Sexual and Gender Minority Violence on Depression, Hazardous Drinking, Condom Use, and HIV Acquisition: An Individual Participant Data Meta-Analysis of the CohMSM, HPTN 075, and Anza Mapema Cohort Studies in Africa
No full textInternational audienceSome sexual and gender minorities (SGM), including men who have sex with men and transgender women, are disproportionately vulnerable to HIV. Many SGM in Africa report experiencing verbal or physical violence due to their sexual and/or gender identities or behaviours. The pathways linking such SGM violence to HIV acquisition are complex. We described experiences of verbal and physical SGM violence and explored pathways to HIV acquisition among SGM assigned male sex at birth using an individual participant data meta-analysis of three African cohort studies: CohMSM (Burkina Faso, Côte d'Ivoire, Mali, Togo), HPTN 075 (Kenya, Malawi, South Africa), and Anza Mapema (Kenya).SGM violence was assessed at baseline and follow-up visits. We fit log-linear sequential conditional mean models using generalised estimating equations to estimate risk ratios linking SGM violence, moderate-tosevere depressive symptoms, hazardous drinking, condom use, and HIV acquisition, adjusted for baseline confounders and previous exposure and outcome. We pooled study estimates using random effects metaanalysis. SGM violence, mostly verbal, was reported by 36% (570/1590) participants at baseline (past 6-12 months), and 20% (321/1590) during the first year of follow-up (past 3-6 months). Baseline SGM violence was not associated with HIV acquisition (pooled adjusted risk ratio [aRR]=1.0, 95%CI 0.5-1.9).During follow-up, SGM violence also showed no clear relationship with HIV, but was linked to depressive symptoms at the same visit (pooled aRR=1.9, 1.5-2.4), in turn associated with hazardous drinking (pooled aRR=1.3, 1.1-1.5). Impacts on condom use were inconclusive. SGM in Africa face high rates of violence, which are associated with depressive symptoms and hazardous drinking -potential routes to HIV vulnerability. While our study did not conclusively demonstrate higher HIV incidence among SGM reporting violence, interventions to reduce violence and support mental health remain crucial.</div
« Musgrave v. Mounson (1623): exploring the shortcomings of early moderninquisitions of lunacy »
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An agent-based model to analyze the influence of IS integration and IS assimilation on the adoption dynamics of a green supply chain: The case of regional consolidation centers
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Diode PIN verticale sur diamant (100) autosupporté à base de couches i et n dopées phosphore
No full textNational audienceCet article présente la réalisation et la caractérisation de diodes bipolaires n + -i-p + en diamant sur substrat autosupporté (100) caractérisées électriquement jusqu'à 600 °C sous vide à l'aide d'un équipement unique en France. Les résultats obtenus mettent en évidence la faisabilité et les performances prometteuses des diodes PIN en diamant pour des applications en électronique de puissance
Mesures µ-OBIC sur diode bipolaire Diamant : une première !
No full textInternational audienceCette communication décrit pour la première fois la réalisation d'une diode bipolaire verticale en diamant qui présente des caractéristiques I(V) en direct et en inverse, pouvant donner lieu à des mesures micro-OBIC. L'OBIC est une technique de caractérisation spécifique permettant d'obtenir une image du champ électrique au sein d'un composant et ainsi d'analyser l'efficacité de ses protections périphériques
Automrophic congruences between torsion cohomological classes
No full textFor two representations of some local division algebra, congruent modulo , giving rise to two Harris-Taylor local systems on the corresponding Newton strata of thespecial fiber of a KHT Shimura varieties, we prove that the -torsion of each of their cohomology groups with compact supports are isomorphic, or equivalently the free quotients of each of the cohomologygroups are congruent modulo . We then deduce the construction of accurate non tempered automorphic congruences for a similitudegroup with signature
Franc CFA et inégalités patrimoniales : Héritage colonial, réformes monétaires et verrou structurel en Afrique de l’Ouest: Analyse critique du franc CFA dans les pays de l’UEMOA et le rôle des acteurs internationaux dans la perpétuation des inégalités économiques et sociales
No full textThis thesis explores the long-term effects of the CFA franc : a colonial-era currency still in use in West Africa on wealth inequalities within WAEMU countries. Combining historical, macroeconomic, and critical approaches, it argues that, despite being framed as a symbol of stability, the CFA franc perpetuates a monetary hierarchy detrimental to endogenous development. It restricts access to credit, savings, and investment, especially in rural areas, reinforcing patterns of exclusion from wealth accumulation. Although recent reforms have been introduced, the system’s core structure remains unchanged, sustained by powerful international actors such as France, the IMF, the ECB, and increasingly, China. This research offers a critical perspective on a structural constraint to equitable development.Ce mémoire interroge les effets persistants du franc CFA, hérité de la colonisation, sur les inégalités de patrimoine dans les pays de l’UEMOA. En croisant une lecture historique, macroéconomique et critique, il montre que cette monnaie, bien que présentée comme un gage de stabilité, perpétue une hiérarchie monétaire défavorable au développement endogène. Elle limite l’accès au crédit, à l’épargne et à l’investissement, notamment en milieu rural, et alimente une logique d’exclusion patrimoniale. Malgré les réformes récentes, les fondements du système restent inchangés, sous l’influence d’acteurs internationaux comme la France, le FMI, la BCE et désormais la Chine. Ce travail propose une lecture engagée d’un verrou structurel au développement équitable