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Etat des lieux des consommations de protoxyde d'azote à visée récréative chez les étudiants en médecine du Limousin
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“Can women be perceived as good as men in sport? Only when doping!”: when social dominance motives shape judgements of women’s doping suspicions in threat situations
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Géométrie des aires dans les manuels français du secondaire et du primaire supérieur (1833 - 1902) : Des savoirs à l'interface des domaines mathématiques, des méthodes d'enseignement et des acteurs éducatifs
No full textThe aim of this thesis is to study how knowledges related to areas appear in French geometry textbooks, aimed at intermediate-level pupils (theoretical school age from 11 to 18). This study covers the period from the creation of upper primary education in 1833, to the reform of secondary education in 1902. It is conducted from both a quantitative and qualitative perspective and draws on the concept of interface to analyse the role played by “geometry of areas” at the intersection of numerous mathematical fields, teaching methods and educational actors. In the first part, the consultation and analysis of original institutional and editorial sources enable us to depict the school context of the time, but also that of the editorial production of the textbooks needed to teach geometry, as well as the issues and objectives of this teaching. The second part presents the constitution of a corpus of 40 manuals and outlines their main characteristics, determined using quantitative methods. In these first two parts, research hypotheses are discussed, to which quantitative analysis provides some answers. These hypotheses concern the profiles of authors and their potential readers, and the supposed compartmentalization of primary and secondary education, already called into question by some historiography. The final section explores from a qualitative point of vue the mathematical methods used to determine, calculate or compare the areas of plane figures, and compares them with the educational objectives linked to this learning, according to the categories of public concerned - upper primary, classical or special secondary school pupils, girls or boys. It also examines the teaching methods envisaged by the authors of the manuals in these different teaching contexts. It follows three key ideas concerning area geometry and its connections with other fields of mathematics : geometry of areas appears as a geometry of constructions and figures, but also as a place for expressing operative techniques and calculations, including algebraic ones, and as a means of initiating students into infinitesimal analysis. By following all these paths, this thesis shows that geometry of areas plays a key role at the interface between the fields of mathematical science, the teaching methods emerging, and the educational actors of the time.Cette thèse a pour objectif d’étudier la manière dont les enseignements relatifs aux aires apparaissent dans les manuels de géométrie français, à destination d’élèves de niveau intermédiaire (d’âge scolaire théorique de 11 à 18 ans). Cette étude s’étend de la création de l’enseignement primaire supérieur en 1833, à la réforme de l’enseignement secondaire de 1902. Elle est menée selon une double perspective quantitative et qualitative, et s’appuie sur le concept d’interface pour analyser le rôle joué par la « géométrie des aires » à l’intersection de nombreux domaines mathématiques, des méthodes d’enseignement, et des acteurs éducatifs. Dans la première partie, la consultation et l’analyse de sources institutionnelles et éditoriales originales permet de dépeindre le contexte scolaire de l’époque, mais également celui de la production éditoriale des manuels nécessaires pour enseigner la géométrie, ainsi que les enjeux et objectifs de cet enseignement. La seconde partie présente la constitution d’un corpus de 40 manuels et en dresse les principales caractéristiques, déterminées via des méthodes quantitatives. Dans ces deux premières parties, des hypothèses de recherche sont discutées, auxquelles l’analyse quantitative apporte des éléments de réponse. Ces hypothèses portent notamment sur les profils des auteurs et de leurs lecteurs potentiels, et sur le cloisonnement supposé entre les ordres primaire et secondaire, déjà remis en question par une partie de l’historiographie. La dernière partie explore d’un point de vue qualitatif les méthodes mathématiques mobilisées pour déterminer, calculer ou comparer des aires de figures planes, en les mettant en regard des objectifs éducatifs liés à ces apprentissages, suivant les catégories de publics concernés — élèves du primaire supérieur, du secondaire classique ou spécial, filles ou garçons. Elle questionne également les dispositifs pédagogiques envisagés par les auteurs des manuels dans ces divers contextes d’enseignement. Elle suit trois idées fortes concernant la géométrie des aires et ses connexions avec les autres domaines des mathématiques : la géométrie des aires apparaît comme une géométrie des constructions et des figures, mais aussi comme un lieu d’expression de techniques opératoires et de calculs, y compris algébriques, ainsi que comme un moyen de s’initier à l’analyse infinitésimale. En suivant toutes ces pistes, cette thèse montre que la géométrie des aires joue un rôle primordial à l’interface des domaines des sciences mathématiques, des méthodes d’enseignement qui émergent alors, et des acteurs éducatifs de l’époque
Rural. De l'histoire du mot « rural » à la construction sociale de la ruralité
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Détection de signatures de vie sur des roches terrestres et martiennes: Contribution des tapis microbiens dans les réponses biogéomorphologiques des sédiments desséchés
No full textInternational audienceDetecting signatures of life in sedimentary rocks lies in the difficulty of distinguishing them from abiotic signals and interpreting their formational conditions, particularly when working on planetary systems that are different from Earth, such as Mars (Corenblit et al., 2023). Research in this field is booming, thanks to the development and deployment of detection tools either in orbit or on the surface. Mars is of great interest due to its early history comparable to Earth during the Noachian period > 3.7 Ga (Lapôtre, 2022). In addition, traces of favourable environmental conditions for the potential development of life have been found for this period, for example in Gale Crater (Rapin et al., 2023). Among the candidates for searching potential signatures of life, Microbially Induced Sedimentary Structures (MISS, Nora Noffke in 1996) have become a target. MISS are characteristic structures resulting from surface sediment disturbances induced by microbial mats (Schieber et al., 2007; Noffke, 2010). Their formational environments may correlate with early Mars conditions, and their terrestrial study is enriched by their representation in both fossil and modern records (Noffke 2015, 2021). The analogy between two planetary systems relates to the principle of abductive inference, which posits that similar (bio)geomorphological processes will result in similar (bio)geomorphological structures (Corenblit et al., 2019). Therefore, it is crucial to develop a clear conceptual framework for processing observations of modern and fossilized textures, forms, and patterns and for discussing the gradient of distinction between abiotic and biotic modalities (Davies et al., 2016).Here, we focused on one type of MISS known as “mat cracks”, the biotic equivalent of abiotic structures “mud cracks” (Noffke, 2010). These are well-represented in the field in both fossil and modern records, and they are robustly repeatable under controlled laboratory conditions. They may correspond to ancient Martian environmental systems as attested by polygonal ridges in Gale Crater, which are characteristic of sustained wet/dry cycles (Rapin et al., 2023). The methodology is based on the visual distinction of biotic and abiotic classes of texture, form, and pattern using different visualisation methods such as photogrammetry and expert visual observations, statistical tools and classification with convolutional neural networks (CNNs). For an initial exploration of the mud crack variability, we set up an ex-situ experiment to produce mud cracks with three types of biofilms and three biomass levels according to variables observed in the field, and using 3D picture dataset of the resulting mud cracks. We have demonstrated significant differences between abiotic and biotic classes and between strain and biomass classes. CNN models outperformed the human-blinded classification by refining the diversity of criteria used and observations such as the textures of the sandy matrix. These significant distinctions and the finesse of the classification provided by artificial intelligence allow us to discuss the interest of the information gain in distinguishing potential textures, forms and patterns that are characteristic of MISS in the field where noise, alteration and erosion can be a problem in identifying the origin of signatures, particularly on Mars.Détecter des signatures de vie dans les roches sédimentaires repose sur la difficulté à les distinguer des signaux abiotiques et d’interpréter leurs conditions de formation, en particulier lorsqu’il s’agit de systèmes planétaires différents de la Terre, comme Mars (Corenblit et al., 2023). La recherche dans ce domaine est en plein essor, grâce au développement et au déploiement d’outils de détection, soit en orbite, soit à la surface. Mars suscite un grand intérêt en raison de son histoire ancienne, comparable à celle de la Terre durant la période du Noachien, il y a plus de 3,7 milliards d’années (Lapôtre, 2022). De plus, des traces de conditions environnementales favorables au développement potentiel de la vie ont été identifiées pour cette période, par exemple dans le cratère de Gale (Rapin et al., 2023). Parmi les candidats dans la recherche de potentielles signatures de vie, les structures sédimentaires induites par activité microbienne (MISS, Microbially Induced Sedimentary Structures, terme introduit par Nora Noffke en 1996) sont devenues une cible d’intérêt. Les MISS sont des structures caractéristiques résultant de perturbations de surface sédimentaires induites par des tapis microbiens (Schieber et al., 2007 ; Noffke, 2010). Leurs environnements de formation peuvent correspondre aux conditions anciennes sur Mars, et leur étude terrestre est enrichie par leur présence dans les archives fossiles comme actuelles (Noffke 2015, 2021). L’analogie entre deux systèmes planétaires repose sur le principe de l’inférence abductive, qui postule que des processus (bio)géomorphologiques similaires conduisent à des structures (bio)géomorphologiques similaires (Corenblit et al., 2019). Il est donc essentiel de développer un cadre conceptuel clair pour traiter les observations de textures, formes et arrangements de formes actuelles et fossilisés et pour discuter du gradient de la distinction entre les modalités abiotiques et biotiques (Davies et al., 2016).Dans cette étude, nous nous sommes concentrés sur un type de MISS connu sous le nom de « mat cracks » (= fissures de tapis microbiens), équivalent biotique des structures abiotiques appelées « mud cracks » (= fentes de dessiccation) (Noffke, 2010). Ces structures sont bien représentées sur le terrain, à la fois dans les archives fossiles et actuelles, et elles sont reproductibles de manière robuste dans des conditions de laboratoire contrôlées. Elles pourraient correspondre à d’anciens systèmes environnementaux martiens, comme en témoignent les crêtes polygonales du cratère de Gale, caractéristiques de cycles mouillage/séchage prolongés (Rapin et al., 2023). La méthodologie repose sur la distinction visuelle entre classes biotiques et abiotiques de textures, formes et arrangements de formes à l’aide de différentes méthodes de visualisation telles que la photogrammétrie, les observations visuelles, des outils statistiques et la classification par réseaux de neurones de convolution (CNN). Pour une première exploration de la variabilité des fentes de dessiccation, nous avons mis en place une expérience ex-situ pour produire des fentes de dessiccation avec trois types de biofilms et trois niveaux de biomasse, selon des variables observées sur le terrain, en utilisant un ensemble d’images 3D des structures obtenues. Nous avons démontré des différences significatives entre les classes abiotiques et biotiques, ainsi qu’entre les classes de souches microbiennes et de biomasse. Les modèles CNN ont surpassé la classification humaine à l’aveugle, en affinant la diversité des critères utilisés et les observations, telles que les textures de la matrice sableuse. Ces distinctions significatives et la finesse de la classification fournie par l’intelligence artificielle nous permettent de discuter de l’intérêt du gain d’information pour distinguer des textures, formes et motifs potentiellement caractéristiques des MISS sur le terrain, où le bruit, l’altération et l’érosion peuvent compliquer l’identification de l’origine des signatures, en particulier sur Mars
A Readiness Level Assessment of Healthcare Facilities in the Democratic Republic of Congo for the Management of Cardiovascular Disease and Diabetes
No full textInternational audienceIntroduction: Sub-Saharan Africa in general, and the Democratic Republic of the Congo (DRC) in particular, is undergoing an epidemiological transition characterized by a more rapid increase in the number of non-communicable diseases (NCDs). However, the level of readiness of the DRC’s healthcare facilities (HFs) to manage these diseases is unknown. Thus, our study aimed to assess these HFs’ level of readiness to manage cardiovascular disease (CVD) and diabetes. Methodology: This cross-sectional study involved 1412 HFs in the DRC, selected by stratified random sampling. They are representative of the country’s 26 provinces. The World Health Organization (WHO) Service Availability and Readiness Survey (SARA) was used. The “readiness” outcome was a composite measure of the capacity of HFs to manage CVD and diabetes. The readiness indicator comprised four domains, and a score of ≥70% indicated “readiness” to manage CVD and diabetes. Informed consent was obtained from the stakeholders, and the ethics committee held a positive opinion. Statistical analyses were performed using STATA 17 software. Results: The average readiness scores of the DRC’s HFs to manage CVD and diabetes are less than 50%, being 38.3% (37.3–39.3) and 39.8% (38.7–40.9), respectively. These scores were less than 40% for CVD and diabetes in rural HFs. They were less than 30% for CVD and diabetes in primary-level HF. No province possesses over 50% of health facilities equipped to address cardiovascular illnesses, and only four provinces (Haut Uele, Kinshasa, Nord Kivu, and Sud Kivu) possess over 50% of health facilities equipped to address diabetes. The provinces with health facilities exhibiting the least preparedness in managing cardiovascular illnesses and diabetes are Nord Ubangi and Sankuru. Only 0.07% (0.01–0.5) of HFs obtained a score ≥ 70% for CVD management, and 5.9% (4.8–7.3) obtained this score for diabetes management. Conclusions: Significant deficiencies must be rectified to enhance service delivery in the management of cardiovascular disease (CVD) and diabetes. Most primary-level and rural facilities demonstrated inadequate preparedness for CVD and diabetes screening and management, exhibiting low readiness scores and limited-service availability in the assessed domains. While secondary-level services are relatively accessible, critical gaps persist that must be addressed to improve readiness for CVD and diabetes care. Healthcare facilities should possess the capacity to deliver recommended services across various tiers, ensuring both service readiness and availability
Cancer in Severe Mental Illness Patients: A Retrospective Study
No full textInternational audienceABSTRACT Objective Severe mental illness (SMI), including schizophrenia, bipolar disorder or depression, constitute a risk factor for premature death. SMI patients die more frequently and earlier of cancer than the general population. Chronic inflammation, lack of cancer screening and substance abuse could explain these premature deaths in SMI patients. The role of SMI in cancer incidence remains uncertain. This study aims to identify the temporal occurrence between SMI and cancer in the case of dual pathology, and to investigate possible associations between specific diagnoses of SMI and cancer locations. Methods We retrieved medical data on more than 2000 SMI patients in care in 2022 with follow‐up for up to 54 years and searched for cancer diagnoses and addictive comorbidities. Results Most SMI patients with cancer had been diagnosed with SMI prior to cancer (85.8%). The most represented cancer was breast cancer (27.2%) followed by cutaneous cancer (16.6%) and prostate cancer (10.6%). No associations were found between pre‐existing SMI and cancer diagnoses as a whole. No associations were found when considering specific psychiatric diagnoses of SMI and precise cancer locations. Psychoactive substance consumption was similar among the different SMI pathologies and were not associated with specific cancer except for alcohol and breast cancer as well as tobacco and lung cancer. Conclusion This study highlights the need to reconsider the complex interaction between SMI and cancer, including their temporal relationship and mutual impact. The link between specific psychiatric diagnoses and cancers should be investigated in larger studies cross‐referencing psychiatric files and cancer‐specific database
Endoscopic En Bloc Vs Piecemeal Resection of Large Colonic Adenomas: Carbon Footprint Post Hoc Analysis of a Randomized Trial
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Determinants of retinopathy and short-term neurological outcomes after cerebral malaria
No full textInternational audienceAbstract Neurological abnormalities are frequent after cerebral malaria (CM) resolves. The identification of survivors that should be prioritized during follow-up after CM is necessary for post-hospitalization care. We analysed social, clinical, and immune determinants of malarial retinopathy (MR) and short-term neurological outcomes after CM. Children aged 24 to 71 months with CM were prospectively followed-up until 28 days after admission at two hospitals in Benin. Direct ophthalmoscopy was performed shortly after admission. Plasma biomarkers were measured at admission. A neurocognitive deficit screener was administered at discharge and 21–28 days after admission. Of 70 children, 20 died before discharge (28.6%). Neurological deficits decreased from 100% on admission to 48.9% at discharge, and to 16.7% at 21–28 days after admission. MR was found in 58% of children. In multivariate analysis, factors associated with MR were a traditional consultation before admission and study site. In addition, neurological deficits were associated with MR (Odds Ratio 5.54 95% CI (1.30–23.54)). In univariate analysis, higher plasma levels of angiopoietin-2 were associated with neurological deficit at discharge and at days 21–28 post-admission. Therefore, MR and endothelium activation may be markers of neurological deficit, the former at hospital discharge and the latter at discharge and at D21–D28 post-admission
Evaluation of an Improved Filtering Method for Strain Measurement at High Temperatures Using 2D-DIC
No full textInternational audienceBackground The Two-Dimensional Digital Image Correlation (2D-DIC) method is widely used as a non-contact full-fieldkinematic measurement, but it presents significant errors related to temperature effects including the image con- trast andheat waves. Consequently, results of mechanical displacement or strain measured by the 2D-DIC method, especially strainsin the elastic domain of materials, is significantly dispersed.Objective The aim of this study is to propose a very simple 2D-DIC method, using commercial DIC software with no needof additional storage to accurately measure strain and displacements at high temperatures, typically at the hot metal formingtemperatures, from 400 ◦C to 750 ◦C.Methods This study demonstrates the influence of temperature effects (radiation and heat waves) on strain measurementsobtained with the 2D-DIC method in the elastic regime (ε < 0.05) of the TA6V titanium alloy material at high tempera-tures. Furthermore, the strain measurement errors at different temperatures were characterized by the Background OrientedSchlieren technique (BOS). Correction methods using temperature-dependent low-pass filters for strain measurement errorsare suggested.Results The correction methods allow separating mechanical strain fields and strain measurement errors caused by tem-perature effects. The efficiency of the correction methods is demonstrated by identifying the Young’s modulus (E) and theThermal Expansion Coefficient (TEC) of the TA6V. After corrections, E and the TEC of the TA6V are close to the referencevalues found in the literature. Conclusion: The coefficient R2 from the linear regression method to determine the Young’smodulus from tensile test at 600 ◦C increases from 0.783 to 0.989, revealing the great potential of using the improved-2D-DIC method for full-field kinematic measurements of mechanical tests at high temperatures