Portail HAL UA (Université d'Angers)
Not a member yet
58742 research outputs found
Sort by
LÊ-GREUEL TYPE FORMULAS FOR SOME MAPPINGS FROM (R^n,0) TO (R^2,0)
No full textWe consider a definable map-germ (f, g) : (R^n,0) → (R^2,0). Under some conditions on f and g, we establish Lê-Greuel type formulas, namely we relate several Euler characteristics of Milnor fibres to Poincaré-Hopf indices of appropriate vector fields. Our method is based on Lagrange multipliers and some polar techniques. We provide a large class of weighted-homogeneous mappings for which our conditions are satisfied
Vignoble et développement territorial : enjeux de valorisation d'une ressource immatérielle: Cas du vignoble nantais
No full textInternational audienceCette publication s’appuie sur un travail préliminaire conduit dans le Pays du Vignoble nantais auprès de différents acteurs locaux intervenant dans différents secteurs d’activités et partageant en commun un ancrage territorial plus ou moins fort ainsi qu’une perception de la dimension culturelle et patrimoniale de leur territoire.L’objectif poursuivi consiste à identifier : - Le rôle du vignoble et des paysages viticoles en tant que ressource immatérielle - Les différentes formes d’appropriation de cette ressource par les différents acteurs - La capacité des acteurs à générer du développement à partir de la ressourceDans un premier temps, nous proposons quelques éléments de cadrage théorique en abordant la question du développement territorial local et le regain d’intérêt pour la proximité et la relocalisation.Ensuite, comme la thématique du colloque porte sur les vins et les territoires, notre proposition suggère d’analyser cette question à l’échelle d’un territoire portant le nom de son vignoble, pour voir dans quelle mesure une ressource qui relève de dimensions diverses : économique (Muscadet), patrimoniale (paysages) et sociale (identification au territoire), sert de substrat au développement et la diversification d’activités à l’échelle locale et confère au territoire un avantage compétitif (François et al., 2006). Dans cette proposition, nous souhaitons appréhender les produits du territoire et le patrimoine naturel en tant que ressource spécifique à valoriser dans une stratégie locale de développement. En termes d’ouverture, nous proposons dans le cadre de ce travail deux perspectives que nous formulons sous forme de questions :1.Comment doit-on considérer la ressource lorsqu’elle est issue d’une activité privée (viticulture), mais qui procure au territoire un signe distinctif profitable à la collectivité et au-delà ?2.Quelle organisation politico institutionnelle pour la gestion des usages de la ressource
Bullying and burnout in French obstetrics and gynecology residency programs: a national cross-sectional study
No full textInternational audienceIntroduction: Prior research has demonstrated high burnout rates during medical residency, namely among obstetrics and gynecology (Ob-Gyn) specialists. Concurrently, reports of workplace bullying, particularly in surgical wards, have risen. However, no studies have evaluated these aspects among French Ob-Gyn residents. This study assessed the prevalence and impact of workplace bullying on Ob-Gyn residents, the relationship between bullying and burnout, and the risk and protective factors influencing burnout. Methods: A national, observational, cross-sectional study was conducted involving 37 French Ob-Gyn residency programs during the 2021-2022 academic year. Data were collected via an anonymous online survey using instruments such as the Maslach Burnout Inventory, Negative Acts Questionnaire-Revised (NAQ-R), and Hospital Anxiety and Depression Scale. Sociodemographic data, working conditions, sources/locations of bullying, and incidence of suicidal ideation were also collected. Multivariable logistic regression was used to analyze associations. Results: Of 625 respondents, 52.4% reported bullying as measured by the NAQ-R. Burnout was present in 18.4%, with notable rates of professional exhaustion (24.3%), depersonalization (34.9%), and diminished personal accomplishment (25.1%). A significative correlation between workplace bullying and burnout was found. Strong social support from superiors emerged as protective against burnout, whereas frequent exposure to bullying, excessive working hours, and high stress levels were identified as major risk factors. Conclusion: Our study reveals that 52.5% of responding residents reported experiencing workplace bullying, and 18.4% met the criteria for burnout. While these findings are concerning and warrant attention, they reflect the experiences of residents who chose to participate in the survey, and may therefore overrepresent those most affected. Nevertheless, the significant association observed between bullying and burnout highlights the need for institutional strategies to better support residents' well-being and ensure a safe, respectful working environment in obstetrics and gynecology residency programs
Le microbiote des semences : diversité, assemblage et transmission
No full textInternational audiencePlants are associated with vast communities of micro-organisms, or microbiota, which contribute to their adaptive value. It is usually acknowledged that most members of the microbiota originate from a local reservoir of diversity, such as the soil. However, a multitude of microbial species use the seed as a dissemination vector. This transmission of micro-organisms via seeds ensures plant microbiota inheritance from one plant generation to the next. Here, we review seed microbiota with a particular emphasis on (1) its diversity, (2) the origin of its members, (3) the processes involved in its assembly, (4) its dynamics during the early stages of crop establishment, (5) its functional role and (6) its potential for microbial engineering in agriculture.Les plantes vivent en association avec de vastes communautés de micro-organismes, ou microbiotes, qui contribuent à la valeur adaptative des plantes. Il est admis que la majorité des membres du microbiote est issue d'un réservoir local de diversité comme le sol. Néanmoins une multitude d'espèces microbiennes utilisent la graine comme vecteur de dispersion. Cette transmission de micro-organismes par les graines permet d'assurer un processus d'héritage d'une partie du microbiote végétal entre générations de plantes. Ce document de synthèse aborde le microbiote des graines en se focalisant sur (1) sa diversité, (2) l'origine de ses membres, (3) les processus impliqués dans son assemblage, (4) sa dynamique lors des premières étapes d'installation des cultures, (5) son rôle fonctionnel et (6) son potentiel pour l'ingénierie microbienne en agriculture
Potagers domestiques et autoproduction dans l’agglomération caennaise : Des pratiques populaires en recomposition face aux enjeux écologiques ?
No full textInternational audienc
Nephrologists’ perception of the French national guidelines in nephrology
No full textInternational audienceIn France, the “Haute Autorité de Santé” (HAS), an independent public scientific authority, regularly publishes guidelines targeted to healthcare professionals. As their implementation is left to the healthcare professionals’ discretion, their perception could influence their application. The aim of this study was to assess the nephrologists’ perception of the HAS guidelines on nephrology in general and on the access to the kidney transplant waiting list. We used a mixed methods approach with an exploratory design combining analysis of qualitative and quantitative data. Nephrologists practicing in France were included. We collected qualitative data in face-to-face semi-structured interviews and identified the main themes through an inductive thematic analysis. We collected quantitative data through an online questionnaire designed based on the qualitative findings. The analysis of interviews with 45 nephrologists (22 women) identified three main themes: (i) nephrologists’ knowledge and sources of information on HAS guidelines in nephrology; (ii) their perception of these guidelines and relevance to medical practice; (iii) age limit to access the kidney transplant waiting list in the 2015 guidelines. The quantitative analysis included 126 nephrologists (47.6% women), among whom 84.1% had already heard about these guidelines. Respectively, 85.8% and 80.2% found the guidelines “clear” and “complete”. Overall, the quantitative data confirmed the qualitative findings. This study shows how nephrologists perceive the HAS guidelines. This will inform discussions on how to make these guidelines more accessible to nephrologists. New studies could be carried out to better quantify and qualify the effect of these guideline
Online Simplex-Structured Matrix Factorization
No full textInternational audienceSimplex-structured matrix factorization (SSMF) is a common task encountered in signal processing and machine learning. Minimum-volume constrained unmixing (MVCU) algorithms are among the most widely used methods to perform this task. While MVCU algorithms generally perform well in an offline setting, their direct application to online scenarios suffers from scalability limitations due to memory and computational demands. To overcome these limitations, this paper proposes an approach which can build upon any off-the-shelf MVCU algorithm to operate sequentially, i.e., to handle one observation at a time. The key idea of the proposed method consists in updating the solution of MVCU only when necessary, guided by an online check of the corresponding optimization problem constraints. It only stores and processes observations identified as informative with respect to the geometrical constraints underlying SSMF. We demonstrate the effectiveness of the approach when analyzing synthetic and real datasets, showing that it achieves estimation accuracy comparable to the offline MVCU method upon which it relies, while significantly reducing the computational cost
MOLECULAR DIAGNOSIS OF RESPIRATORY VIRAL INFECTIONS IN CYSTIC FIBROSIS, SPUTUM VERSUS NASOPHARYNGEAL SAMPLES
No full textInternational audienceBackground: Respiratory viral infections in people with Cystic Fibrosis (pwCF) significantly impact disease progression, and their molecular diagnosis should be part of the recommendations. Sputum, the routinely used specimen for bacterial culture, could also be used for viral molecular diagnosis, avoiding an additional invasive nasopharyngeal swab or aspirate. Our primary objective was to evaluate whether invasive nasopharyngeal samples (NP) and non-invasive sputum specimens are equally accurate for the diagnosis of viral infections in pwCF.Methods: We conducted a prospective and multicentre study in 11 French CF centres. A total of 111 pwCF (children or adults, all able to expectorate) presenting with acute respiratory symptoms were included. Each provided paired NP and sputum, which were analysed using multiplex PCR panels detecting a broad spectrum of respiratory viruses, in addition to standard clinical evaluation and microbiological findings.Results: Among 111 paired samples, 69 NP and 64 sputa tested positive for ≥1 virus, with 94 pairs yielding concordant results (58 both positive, 36 both negative). Overall NP-sputum agreement was substantial (Cohen's κ = 0.68 [0.60; 0.75]), and even higher for the most prevalent viruses (enterovirus/rhinovirus, κ = 0.74 [0.65; 0.80] and influenza viruses, κ = 0.95 [0.87; 0.97]). The detection of a virus in one or both specimens was independent of the presence of a bacterial pathogen in sputum culture.Conclusion: These results confirmed the suitability of sputum sampling as an alternative to NP sampling for the diagnosis of viral respiratory infection in pwCF, ensuring patients' comfort
Long-term oral exposure to finasteride and different doses of minoxidil induces testicular and epididymal alterations in adult Balb/c mice
No full textInternational audienceOral finasteride and topical minoxidil are approved treatments for androgenetic alopecia, while low-dose oral minoxidil has emerged as a promising off-label alternative. Despite its vasodilatory and androgen-modulating properties, the minoxidil effects on male reproductive health remain poorly understood. Given its growing off-label use and potential reproductive impact, this study aimed to evaluate the histopathological, hormonal, and oxidative stress effects of oral minoxidil on the testes and epididymides of adult Balb/c mice. A total of 120 animals were divided into six groups (n = 20) receiving daily oral doses of water, vehicle, finasteride (5 mg/kg), or minoxidil (2.5, 5, or 7.5 mg/kg). Half were euthanized after 42 days and the remainder after 84 days of treatment. On the 42nd day, both minoxidil and finasteride induced testicular structural alterations, including vacuolization of the seminiferous epithelium, reduction in seminiferous epithelium height, and increase in the proportion of Leydig cells. In the minoxidil-treated groups, these alterations were accompanied by decreased serum estradiol levels and oxidative imbalance, suggesting these might be underlying mechanisms of minoxidil-induced reproductive toxicity. After 84 days, although no significant changes were observed in the estradiol levels and oxidative status, testicular structural alterations persisted, characterized by continued vacuolization of the seminiferous epithelium and decreased seminiferous epithelium proportion after finasteride and minoxidil treatments. Although no dose-dependent minoxidil effect was observed, the dose of 5 mg/kg more frequently induced alterations. Histological epididymal changes were identified with both drugs at both time points. However, only finasteride significantly reduced sperm transit time (at 42 and 84 days) and cauda sperm count (at 84 days). These results suggest that while both minoxidil and finasteride induce broader testicular alterations, finasteride significantly affects epididymal function. This study highlights potential reproductive risks associated with long-term oral minoxidil use and emphasizes the importance of clinical studies assessing its safety in male reproductive health, particularly in individuals of reproductive age
