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Utility of tumor and non-tumor biopsies during percutaneous radiofrequency ablation for hepatocellular carcinoma
No full textInternational audienceBackground & aims: We aimed to assess the safety and diagnostic/prognostic value of tumor and non-tumor biopsies systematically collected during radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC).Methods: We prospectively included patients with a first diagnosis of HCC who underwent tumor and non-tumor biopsies during percutaneous RFA between 2015 and 2021. We analyzed the complications, percentage of diagnostic tumor biopsies, ability to perform molecular biology, and the non-tumor liver biopsy results, and correlated histology with prior non-invasive diagnosis and oncological outcomes.Results: In total, 248 patients (86% male, median age 68) with 302 tumors treated by RFA and with available tumor biopsy were included. HCC was single in 78% and bifocal in 21% of patients, with a median size of 24 mm. Bleeding occurred in six cases (1.9%) without related deaths. Biopsies enabled HCC diagnosis in 66% of cases, with positivity linked to nodule size (p <0.0001), location (p = 0.04), and ultrasound visibility (p = 0.004). A discrepancy between prior tumor board and subsequent histological diagnosis was observed in 5% of cases. Among the 302 biopsies, 34% were non-diagnostic, 61% were HCC, 3% were cholangiocarcinoma (CCA)/hepatocholangiocarcinoma (cHCC-CCA), and 2% were dysplastic nodules. Survival was shorter in patients with CCA/cHCC-CCA (p <0.001). Macrotrabecular-massive HCC was associated with higher rates of global tumor recurrence (p = 0.037). More than 25% of tumor cells in paraffin-embedded samples were associated with expression of cancer genes on transcriptomic analysis of the corresponding frozen samples, assuring their usefulness for molecular analysis. In non-tumor biopsies, cirrhosis was histologically confirmed in 82% of cases, with a 15% discrepancy between diagnosis of cirrhosis at tumor board and on biopsy.Conclusion: Systematic tumor and non-tumor biopsy during RFA for a first diagnosis of HCC is feasible, safe, and brings valuable diagnostic, therapeutic, and prognostic data.Impact and implications: Tumor and non-tumor biopsies during radiofrequency ablation for hepatocellular carcinoma are both safe and feasible, with a low complication rate and no procedure-related deaths. We demonstrated the diagnostic utility of biopsies, revealing discrepancies in 5% of cases between tumor board and histological results, which could refine patient management strategies. We identified significant associations between hepatocellular carcinoma subtypes and recurrence rates, and found that molecular analysis based on frozen tumor samples is feasible in most cases and could be guided by the percentage of tumors cells on paraffin-embedded sampl
Influence of process parameters on flexural properties of composites reinforced with continuous fiber produced by material extrusion
No full textInternational audienceAdditive manufacturing revolutionized the production of personalized objects from 3D models across various industries, including medical, aerospace and automotive, primarily through the widely accessible material extrusion process. Despite additive manufacturing advantages, the parts fabricated using additive manufacturing often exhibit lower elastic properties compared to conventionally injection-molded thermoplastic components. Adding fiber-reinforced polymer composites during printing has a significant influence both on tensile and flexural strength, as well as on the overall quality of resulting composite structure. Adding a low volume of reinforcement (<15%) to a sample is advantageous without increasing the stiffness of the sample significantly. This study aims at investigating the impact of low reinforcement volume and placement on the flexural properties of samples while assessing the repeatability of the printing process through 3-point bending tests. A finite element model of the test is also proposed in order to predict the flexural properties of samples. Process induced defects such as voids are modeled in the samples as the results show that the addition of fiber-reinforced polymer led to an increase in the porosity rate. The experimental results of 3-point bending test were compared with those of finite element analysis. Printing rules aimed at minimizing errors and addressing limitations inherent in the printing process are defined in the current study
Optimization of artificial multifunctional K0.5Na0.5NbO3 - CoFe2O4 ceramics
No full textInternational audienceLead and rare earth-free (1-x)K0.5Na0.5NbO3– (x)CoFe2O4 composites (where x = 0.05, 0.10 and 0.20), consisting of ferroelectric K0.5Na0.5NbO3 (KNN) matrix and ferromagnetic CoFe2O4 (CFO) nano-inclusions, were densified via spark plasma sintering (SPS) to develop multifunctional materials. X-ray diffraction (XRD) confirmed the absence of secondary phases. High resolution scanning electron microscopy (HR-SEM) revealed dense microstructures, with increasing CFO grain size at higher CFO content. Energy dispersive X-ray spectroscopy (EDS) mapping and scattered scanning near-field optical microscopy (s-SNOM) confirmed CFO distribution in KNN matrix. Ferroelectric hysteresis loops demonstrated ferroelectricity in all composites. Dielectric measurements howed relaxation behavior with increasing losses for higher CFO content. Magnetic analysis at room temperature indicated a dominant ferromagnetic behavior, with superparamagnetic and diamagnetic contributions from CFO and KNN, respectively. Our complete full knowledge studies functionalities will be helpful to build ceramics architectures suitable for magneto-electric propertie
Standing-sphere blowup solutions for the nonlinear heat equation
No full textInternational audienceIn this paper, we construct a singular standing ring solution of the nonlinear heat in the radial case. We give rigorous proof for the existence of a ring blow-up solution in finite time. This result was predicted formally by Baruch, Fibich and Gavish [BFG10]. We also prove the stability of these dynamics among radially symmetric solutions
Talking about Migration in Times of Crisis: A Textual Analysis of Narratives by IOM and UNHCR on Migrants and Refugees
No full textInternational audienceIn the absence of a binding and coherent international migration regime, the global governance of migration relies on normative narratives produced by UN agencies and other intergovernmental forums, in line with the discursive legitimacy traditionally associated with international organizations. Such narratives impact migrants, asylum-seekers, and refugees because they support certain policy frameworks among member states. Yet, global migration governance remains fragmented, especially as far as the long-standing divide between the International Organization for Migration (IOM) and the Office of the United Nations High Commissioner for Refugees (UNHCR) is concerned. This article contributes to this discussion by applying corpus-assisted critical discourse analysis to the narratives produced by these two organizations. The article identifies some of the dominant worldviews in the narratives of IOM and UNHCR. Results show that IOM and UNHCR have distinct worldviews, associated with different textual patterns, and that, while IOM’s textual productions seem to influence UNHCR’s discourses, the opposite is less true. This would support the view that IOM is currently the leading actor in terms of framing migration, thereby exerting a strong influence on global migration governance
Hausdorff dimension and exact approximation order in R^n
No full textInternational audienceGiven a non-increasing function ψ : N → R + such that s n+1 n ψ(s) tends to zero as s goes to infinity, we show that the set of points in R n that are exactly ψ-approximable is non-empty, and we compute its Hausdorff dimension. For n ≥ 2, this answers questions of Jarník and of Beresnevich, Dickinson and Velani.</div
Groupes arithmétiques et approximation diophantienne
No full textInternational audienceNous développons une théorie de l'approximation diophantienne dans les variétés de drapeaux, obtenues comme quotient d'un groupe de Lie semi-simple défini sur Q par un sous-groupe parabolique. En nous appuyant sur des résultats de la théorie des groupes arithmétiques, dûs entre autres à Borel et Harish-Chandra, et à Margulis et ses collaborateurs, nous démontrons dans ce cadre des généralisations des théorèmes classiques de l'approximation diophantienne
La science de la durabilité appliquée à la médecine traditionnelle en Polynésie française : définition et présentation du projet SustainMedPol
No full textInternational audienceThe sustainability science is a new discipline, emerging as a result of the environmental, social, and economic challenges in the contemporary society. This interdisciplinary approach aims to provide answers to the 169 targets of the Sustainable Development Goals (SDGs). Preserving the knowledge of indigenous peoples is one of these SDGs. Especially, traditional medicine offering culturally acceptable, available, and cheap care, can be a basis for the development of sustainable health solutions. However, traditional medicine has ecological, sociocultural, scientific and regulatory challenges that sustainability science should answer to ensure its long-term survival. In French Polynesia, traditional medicine is the most practiced primary medicine, within more than 300 medicinal plants used to treat several illnesses. Nevertheless, since the 19th century, its practice had encountered many obstacles. Thus, the project funded by the French National Research Agency, “SustainMedPol”, lasting three years, aims to preserve, support, and valorise the traditional medical knowledge from French Polynesia by the proposition of solution implementing sustainable actions.La science de la durabilité est une discipline nouvelle, apparue à la suite des défis environnementaux, sociaux et économiques auxquels font face les sociétés contemporaines. Son approche interdisciplinaire a pour but d’apporter des éléments de réponse aux 169 cibles des Objectifs de Développement Durable (ODD) des Nations-Unies. La conservation des savoirs des peuples autochtones fait partie de ces ODD. En particulier, la médecine traditionnelle, offrant des soins culturellement acceptables, disponibles et abordables, peut servir de base pour le développement de solutions durables en santé. Cependant, la médecine traditionnelle fait face à plusieurs enjeux, écologiques, socioculturels, sanitaires et réglementaires auxquels la science de la durabilité se doit de répondre afin d’assurer sa pérennité. En Polynésie française notamment, la médecine traditionnelle reste la première médecine pratiquée, avec plus de 300 plantes médicinales employées pour traiter une grande variété de maladies. Pour autant, depuis le 19ème siècle, sa pratique fait face à de nombreux obstacles. Ainsi, le projet financé par l’Agence Nationale de la Recherche « SustainMedPol » (2023-2026) s’inscrit dans une démarche de préservation et d’aide à la reconnaissance des savoirs traditionnels en Polynésie française en proposant des solutions qui répondent à ces différents enjeux
Adoption of HIV preexposure prophylaxis (PrEP) among female sex workers (FSWs) in Côte d’Ivoire: complex trajectories and early adopters
No full textInternational audienceIntroductionThe ANRS 12381 PRINCESSE project (November 2019 - June 2023) implemented community-based sexual and reproductive health care, including preexposure prophylaxis (PrEP), for female sex workers (FSWs) in the San Pedro region of Côte d'Ivoire, 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”.MethodsA total of 489 women were enrolled in the PRINCESSE cohort. This analysis included 400 FSWs eligible for PrEP (HIV-negative, HBsAg-negative at baseline) enrolled up to December 2022 (i.e. enrolled at least 6 months before cohort closure). Clinical records were analyzed to describe PrEP cascade, follow-up, and PrEP trajectories. A multivariable logistic regression identified factors associated with PrEP early adopters.ResultsThe overall PrEP cascade showed that 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. attached figure showing individual trajectories, each line representing a participant's PrEP journey): 15% never initiated PrEP; 39% initiated PrEP before stopping and expressing they were not interested anymore; 18% re-initiated PrEP after an episode of non-interest”; and 28% initiated and never expressed non-interest at a later stage. The last two groups were considered as “early adopters”. Significant factors associated with early PrEP adoption were the usual price of intercourse with clients <1500 FCFA (i.e. 2.3 EUR) (aOR=2.4 [1.2-4.8]) and working in brothels (aOR=3.2 [1.6-6.6]).ConclusionsIn 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 and demand creation
Boundedness of discounted tree sums
No full textLet (V(u),\, u\in \T) be a (supercritical) branching random walk and (\eta_u,\,u\in \T) be marks on the vertices of the tree, distributed in an i.i.d.\ fashion. Following Aldous and Bandyopadhyay \cite{AB05}, for each infinite ray of the tree, we associate the {\it discounted tree sum} which is the sum of the taken along the ray. The paper deals with the finiteness of . To this end, we study the extreme behaviour of the local time processes of the paths . It answers a question of Nicolas Curien, and partially solves Open Problem 31 of Aldous and Bandyopadhyay \cite{AB05}. We also present several open questions