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PROPAGATION OF WAVE PACKETS CLOSE TO CONICAL INTERSECTIONS
No full textIn this paper, we study the propagation of wave packets close to conical intersections with respect to a system of two Schrödinger equations presenting a codimension 2 crossing. We focus on the dynamics that occur when the wave packets pass through an area close to the crossing, and our main results provide an explicit formula for the outgoing wave packet in terms of the incoming one, with a complete description of its phase and of the classical trajectories it follows, including a drift
La mise en image des déchets dans la ville : travail et systèmes
No full texthttps://www.revue-urbanites.fr/vu-gouchon-2/The 2024 Doctoriales de Rudologie were held at the University of Le Mans from February 5 to 7, 2024, bringing together more than sixty researchers around the theme “What the filthy tells us about the world: studying waste in the humanities and social sciences (HSS).” The event brought together researchers and doctoral students to discuss the epistemological, methodological, and reflexive issues involved in the study of waste. Following this event, several participants contributed to the creation of this portfolio of field photographs, with the aim of showing the diversity and vitality of doctoral research and its approaches, and offering an introduction to the analysis of issues associated with waste and what it says about urban spaces in the North and South.Waste contributes to the structuring of urban space and raises socio-spatial, economic, and environmental issues that are addressed by rudology. The texts and photographs presented here are rooted in the field of territorial ecology and, more broadly, in that of political ecology, adopting a critical approach and denouncing the context of socio-ecological crises in which waste situations unfold. This portfolio presents the diversity of possible images of waste objects, the people and territories associated with them. The images and texts seek in particular to highlight the unthought aspects of waste, sometimes its omnipresence, sometimes the dynamics of invisibility—of flows and materials, but also of places, people, and the work involved—that are attached to it.The first part of this portfolio focused on issues related to objects and materials, their definition and presence in the city, as well as the specificities of organic matter. This second part presents photographs focusing on waste workers and urban waste management systems.Each photograph is accompanied by a free text explaining the representation of waste in the city.Les Doctoriales de Rudologie 2024 se sont tenues à l’Université du Mans du 5 au 7 février 2024, réunissant plus d’une soixantaine de chercheur⸱ses autour du thème « Ce que l’immonde dit du monde : étudier les déchets en Sciences Humaines et Sociales (SHS) ». L’événement a rassemblé chercheur·ses et doctorant·es autour des enjeux épistémologiques, méthodologiques et réflexifs de l’étude des déchets. À la suite de cet événement, plusieurs participant·es ont contribué à la création de ce portfolio constitué de photographies de terrain, avec comme objectif de montrer la diversité et la vitalité des recherches doctorales et de leurs approches, et de proposer une introduction à l’analyse des enjeux associés aux déchets et à ce qu’ils disent des espaces urbains dans les Nords et dans les Suds.Les déchets participent d’une structuration de l’espace urbain et soulèvent des enjeux socio-spatiaux, économiques et environnementaux dont la rudologie1 rend compte. Les textes et photographies présentés ici s’ancrent dans le champ de l’écologie territoriale et, plus largement, dans celui de l’écologie politique, adoptant une approche critique et dénonçant le contexte de crises socio-écologiques, au sein duquel les situations détritiques se déploient. Ce portfolio présente la diversité des mises en image possibles de l’objet déchet, des personnes et des territoires qui s’y rapportent. Les images et les textes s’appliquent notamment à souligner les impensés autour des déchets, tantôt leur omniprésence, tantôt les dynamiques d’invisibilisation – des flux et des matières mais également des lieux, des personnes et du travail fourni – qui s’y attachent
Profile of pregnant women complying or not with physical activity recommendations during the second trimester of pregnancy: a French pilot study
No full textInternational audienceInsufficient physical activity (PA) during pregnancy is a global public health concern. The aims of this study were: i) to determine retrospectively PA and sedentary time in women in the second trimester of pregnancy, and ii) to identify factors that influence adherence to the French National College of Midwives guidelines on PA (≥150 minutes of moderate to high-intensity PA per week). Methods: This cross-sectional, single-centre study, conducted at the University Hospital of Rennes, included 195 pregnant women. PA levels and sedentary time before and during the second trimester of pregnancy were determined using an anonymous self-report questionnaire. The self-reported PA levels were compared to the guidelines on PA. Bivariate analyses and Poisson generalized linear regression models were used to identify factors associated with non-compliance to such guidelines. Results: Only 30.7 % of pregnant women reported the recommended PA levels in the second trimester of pregnancy. Sedentary time and adherence to the PA guidelines were not associated. Fatigue was the most frequently cited reason for insufficient PA (71.6 %). Preconception PA level was the strongest predictor of adherence. Body mass index >25 kg/m², <2 years of higher education, limited access to transportation and sports facilities, and living in a town with <2.000 inhabitants also were associated with lower PA levels. Conclusion: Adherence to the PA recommendations is low among French pregnant women. Public health initiatives should emphasize PA importance before pregnancy and provide tailored support throughout gestation. Future studies should explore the interplay between PA, sedentary time and pregnancy outcomes
Recherche de cibles antigéniques d’intérêt dans les leucémies aigües lymphoblastique B de l’enfant
No full textBackground: Monoclonal antibodies or autologous anti-CD19 CAR-T cells have revolutionized the treatment of relapsed or refractory B-acute lymphoblastic leukemia (BCP-ALL). However, after these mono-antigen targeting immunotherapies, tumor escape through antigenic modulation accounts for almost 40% of relapses. Multi-antigens targeting strategies should be developed and it is therefore urgent to identify and validate new targets. Methods: Extensive immunophenotyping of 13 marrow samples from pediatric patients with BCP-ALL was performed using the Biolegend® Human Cell Surface Marker Screening Kit. Long-term killing assays were performed, by using human T cells genetically modified to express the murine CD16, previously developed in the laboratory, to assess whether targeting each antigen alone or in combination with murine monoclonal antibodies could lead to leukemic cell lysis by antibody dependant cellular cytotoxicity (ADCC). Results: Thirteen highly expressed antigens were selected. Of these, only a few lead to ADCC mediated lysis when targeted. For the majority of BCP-ALL tested, the most significant lysis was observed by targeting CD24 and CD156c. Multi-targeting ADCC assays revealed that double targeting of CD24-CD123 appeared to be even more effective. Surprisingly triple targeting was associated with a reduction in ADCC activity. Conclusion: CD24 emerged as an effective target in BCP- ALL, and the combination of CD24 and CD123 as a potential effective double-targeting strategy. The combination of different recognition modalities (e.g. a chimeric antigen receptor and CD16) should be tested to determine whether it provides synergistic cytotoxic activity in triple targeting strategies.Contexte : Les anticorps monoclonaux ou les cellules CAR-T anti-CD19 autologues ont révolutionné le traitement des leucémies aigües lymphoblastique B (LAL-B) réfractaires ou en rechute. Cependant, au décours de ces thérapies ciblées, près de la moitié des patients rechutent par échappement tumoral via une modulation antigénique. Des stratégies de ciblage de plusieurs antigènes simultanément doivent être développées. Il est donc urgent d'identifier et de valider de nouvelles cibles. Méthodes : Un immunophénotypage large a été réalisé sur 13 échantillons de moelle provenant de patients pédiatriques atteints de LAL-B à l'aide du Biolegend® Human Cell Surface Marker Screening Kit. Des tests de cytotoxicité sur 24h, réalisés avec des LT équipés du CD16 développés au laboratoire, ont été menés afin de déterminer si la reconnaissance des antigènes sélectionnés, par des anticorps monoclonaux murins, pouvait conduire à la lyse des cellules leucémiques par cytotoxicité cellulaire dépendante des anticorps (ADCC), Résultats : 13 antigènes fortement exprimés ont été sélectionnés. Seuls quelques-uns d'entre eux induisent une lyse par ADCC une fois reconnus par les anticorps murins et les LT-CD16. Pour la majorité des LAL-B testées, la lyse la plus importante a été observée en ciblant CD24 et CD156c. Les tests d’ADCC en multiciblage ont révélé que le double ciblage de CD24-CD123 pouvait induire une ADCC parfois plus efficace. De manière surprenante, le triple ciblage a été associé à une réduction de l'activité ADCC. Conclusion : Le CD24 est apparu comme une cible d’intérêt dans la LAL-B, et la combinaison du CD24 et du CD123 comme une stratégie de double ciblage potentiellement efficace. La combinaison de différentes modalités de reconnaissance (par exemple, un récepteur d'antigène chimérique et le CD16) devrait être testée pour déterminer si elle fournit une activité cytotoxique synergique en triple ciblage
Fuzzy group fixed-effects estimation with spatial clustering
No full textInternational audienceThe paper discusses the problem of estimating group heterogeneous fixed-effect panel data models under the assumption of fuzzy clustering, that is each unit belongs to all the clusters with a membership degree. To enhance spatial clustering, a spatio-temporal approach is considered. An iterative procedure, alternating panel data estimation and spatio-temporal clustering of the residuals, is proposed. The proposed method can be of relevance to researchers interested in using fuzzy group fixed-effect methods, but want to leverage spatial dimension for clustering units. Two empirical examples, the first on cigarette consumption in the US states and the second on non-life insurance demand in Italy, are presented to illustrate the performance of the proposed approach. The spatial fuzzy GFE model reveals important regional differences in both the US cigarette consumption and non-life insurance determinants in Italy. In the case of the US, we found a distinction in two main clusters, East and West. For the Italy provinces data, we find a distinction in North and South clusters. Regarding the regression results, for cigarette consumption data, different from the previous studies, we find that the smuggling effect is significant only in east regions, thus suggesting localised impacts of bootlegging. In the context of Italian non-life insurance demand, we find that while population density explains insurance consumption in northern provinces, the trust issues in the south explain the lower insurance demand
Prevalence of OATP1B-Mediated Drug-Drug Interactions in an Academic Medical Center
No full textInternational audienceOATP1B is a key transporter involved in hepatic drug uptake, where its inhibition can significantly increase plasma drug levels, leading to potential adverse effects. This retrospective study aimed to determine the prevalence of potential drug-drug interactions (pDDIs) mediated by the hepatic transporter OATP1B1/3 in a cohort of 44,877 patients hospitalized at Rennes Academic Medical Center, using data from the Clinical Data Warehouse. We analyzed prescription rates of OATP1B substrates and inhibitors and estimated the prevalence of pDDIs, assessed the consistency of pDDI identification across different drug interaction databases, and performed a literature review of identified OATP1B-based pDDIs. The identification of pDDIs across different drug databases showed inconsistencies, with limited overlap and variability in reported interactions. Among hospitalized patients, 6954 (15.5%) received OATP1B substrates, while 408 (0.9%) received inhibitors, leading to 106 pDDIs observed in 99 patients (0.2%). The pDDI rate varied significantly depending on the inhibitor used, reaching up to 39.1% in patients treated with ciclosporin. Statins accounted for a large proportion of pDDIs, emphasizing the potential risks, especially in multidrug regimens. Commonly involved inhibitors included FDA drugs such as ciclosporin, clarithromycin, and rifampicin. The clinical relevance of these interactions remains uncertain due to the limited availability of supporting evidence and the restricted list of well-characterized OATP1B substrates and inhibitors. This study highlights the complexity of OATP1B-mediated pDDIs and the need for increased clinical awareness and further research to improve the detection and characterization of such pDDIs, particularly for high-risk drugs with a narrow therapeutic index
Splenectomy during cytoreductive surgery in advanced epithelial ovarian cancer can be predicted
No full textInternational audienceIntroduction: Splenectomy may be necessary for complete cytoreductive surgery (CRS) in advanced stage epithelial ovarian cancer (AS-EOC), potentially raising perioperative morbidity and necessitating specific patient management. Objective: This study aimed to develop a predictive score of splenectomy in CRS of AS-EOC. Materials and methods: Data from histologically confirmed AS-EOC (FIGO IIB-IV) before CRS and diagnosed between 01/01/2000 and 01/06/2017, were extracted from the FRANCOGYN multicentric database (14 French hospitals). After identifying predictive factors of splenectomy, we performed a logistic regression to develop a prediction model and construct a risk score, allowing identification of a high-risk group. Model discrimination was assessed using a Receiver Operating Characteristic (ROC) curve. Decision Curve Analysis (DCA) was then conducted to evaluate the model's net clinical benefit across a range of threshold probabilities. Results: Among 1288 patients included, 7 % (n = 91) underwent splenectomy. Four independent variables statistically associated with splenectomy were identified: age <60 years (aDOR = 1.76, 95 % CI [1.13-2.75], p = 0.015), omental cake (aDOR = 2.12, 95 % CI [1.11-4.08], p = 0.024), diaphragmatic carcinosis (aDOR = 2.36, 95 % CI [1.34-4.18], p = 0.001), and digestive involvement at initial CT and/or laparoscopy (aDOR = 3.24, 95 % CI [1.93-5.43], p < 0.001). The ROC-AUC of this prediction model was 0.76. Patients meeting all 4 criteria with a maximum of 10 points defined the high-risk group and had a splenectomy probability of 32 % (95 % CI [22.00-44.31]), with a specificity of 95.8 % (95 % CI [94.5-96.9]) and a positive likelihood ratio of 6.31 (95 % CI [4.08-9.78]). The DCA showed a positive net clinical benefit of the model between 15 % and 40 % threshold probabilities. Conclusion: Using a simple 4-variable predictive score, patients at high risk of splenectomy during CRS in AS-EOC could be identified to improve patients' preoperative information and perioperative management
Dynamic spatial beam shaping for ultrafast laser processing: a review
No full textInternational audienceThis review examines the state-of-the-art in spatial manipulation of ultrafast laser processing using dynamic light modulators, with a particular focus on liquid crystal-based systems. We discuss phase modulation strategies and highlight the current limitations and challenges in surface and bulk processing. Specifically, we emphasize the delicate balance between high-fidelity beam shaping and energy efficiency, both critical for surface and bulk processing applications. Given the inherent physical limitations of spatial light modulators such as spatial resolution, fill factor, and phase modulation range. We explore techniques developed to bridge the gap between desired intensity distributions and actual experimental beam profiles. We present various laser light modulation technologies and the main algorithmic strategies for obtaining modulation patterns. The paper includes application examples across a wide range of fields, from surgery to surface structuring, cutting, bulk photo-inscription of optical functions, and additive manufacturing, highlighting the significant enhancements in processing speed and precision due to spatial beam shaping. The diverse applications and the technological limitations underscore the need for adapted modulation pattern calculation methods. We discuss several advancements addressing these challenges, involving both experimental and algorithmic developments, including the recent incorporation of artificial intelligence. Additionally, we cover recent progress in phase and pulse front control based on spatial modulators, which introduces an extra control parameter for light excitation with high potential for achieving more controlled processing outcomes.</div
