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Towards a non-invasive methodology for assessing apple ripening state in real time during refrigeration storage
No full textInternational audienceRefrigerated storage is one of the most commonly used methods for extending the shelf life of apples after harvesting. Although coupled with controlled atmosphere to further increase shelf life, implementing a controlled atmosphere is not always feasible. Quality of apples is often evaluated visually or through destructive measurement techniques. These time-consuming methods do not easily reflect the current fruit's metabolic state. The metabolic activity of apples is strongly influenced by the plant hormone ethylene, which the fruit both produces and absorbs. In climacteric fruits such as apples, ethylene production typically follows a concave curve, which in turn induces a similar pattern in the fruit’s aerobic respiration. This characteristic curve indirectly indicates the fruit's ripeness. Therefore, it is of great interest to develop a method that can capture and predict respiration kinetics in real time, ultimately determining the optimal timing for removing apples from cold storage for delivery. To address this purpose, we propose a measurement system capable of real-time respiration monitoring and a mechanistic model to describe the evolution of fruit respiration over time, which parameters are estimated using reverse approach on Pink Lady apples experimental data at ambient temperature. However, the implementation of this real-time approach under cold storage conditions remains a challenge and requires further investigation
Genetic and genomic variability of Spiroplasma and Midichloria endosymbionts associated with the tick Ixodes frontalis
No full textInternational audienceIxodes frontalis, an ornithophilic tick species, is widely distributed all over Europe exhibiting two genetically diverging haplogroups based on differences in the cytochrome c oxidase subunit 1 mitochondrial gene. Despite its broad distribution, little is known about the presence of symbiotic bacteria in I. frontalis, while symbionts are generally widespread in ixodid ticks and responsible for important effects on host fitness. We collected I. frontalis from France and Italy (n = 277) and assessed that the most prevalent haplogroup was A (73%). We then investigated the presence of the symbionts, Midichloria mitochondrii and Spiroplasma ixodetis. They were both found at a high prevalence in adult ticks (66% and 77% respectively), while the number of positive immature ticks was significantly lower (18% for both). The experimental analysis of larvae hatched from egg clutches obtained from four females hints at vertical transmission of both symbionts. We obtained three genomes of Spiroplasma and one of Midichloria, and used them to perform comparative genomic analysis. Average nucleotide identity among available Spiroplasma or Midichloria genomes from I. frontalis are all extremely high, suggesting low genetic variability for both symbionts. Gene presence/absence analysis confirmed the presence of B vitamin synthesis genes in the genome of M. mitochondrii, and also showed the presence of the ETX/MTX2 gene, the RIP family and a partial Spaid-like gene in S. ixodetis. This gene repertoire indicates a nutritional role for Midichloria, while for S. ixodetis we hypothesize a role of this bacterium as a defensive symbiont or a manipulator of the host reproduction
Opinion and report of the French Agency for Food, Environmental and Occupational Health and Safety (ANSES) relating to an analysis of the health risks associated with exposure to caterpillars with stinging hairs and the development of management recommendations
No full textXavier Bailly et Elsa Jourdain ne sont pas auteurs mais relecteurs du rapportInternational audienceSeveral species of Lepidoptera with caterpillars bearing urticating hairs are increasing their range in metropolitan France from year to year, such as the pine processionary (Thaumetopoea pityocampa Denis et Schiffermüller 1775) whose presence was historically limited to the south of France, and which is gradually being observed in the north and at higher altitudes. The procession period also seems to be appearing earlier. Climate change could have an impact on the range and phenology of this species, as well as other species of Lepidoptera with caterpillar bearing urticating hairs. Urticating caterpillars, which can trigger diffuse urticariform papules and allergic reactions for human people through contact with the skin, mucous membranes or inhalation, represent a health issue. These caterpillars also cause a health risk for animals and can have an impact on plants due to the resulting defoliation. This risk assessment therefore focused on the risk posed by these urticating caterpillars in areas where they have been established for a long time as well as in areas where they currently do not occur but could be colonized in the short or medium terms. One of the outputs of the evaluation consisted in identifying 55 different species of Lepidoptera with urticating caterpillars, for metropolitan France, but also for the overseas regions, based on the review by Kawamoto and Kumada (1984) and the GBIF database. In addition, detailed sheets for the well‐known species were drawn up, describing in particular their range, their phenology and the period when the urticating stages occur. A literature review as well as data from poison control centres and the analysis of the results of two surveys (of three associations of dermatologists/allergists and of occupational populations at risk) allowed to characterize the contexts of exposure and the human populations at risk. Concerning animal health, in addition to an epidemioclinical description based on the literature, data from veterinary poison control centres were analyzed in the specific case of dog exposure to the pine processionary between 1999 and 2021 in metropolitan french territory. Given the impact of these species of Lepidoptera on ecosystems, due to the defoliation they induce, this scientific opinion investigated the impact of these species on ecosystem services. The socio‐economic impacts of defoliations and risk management measures implemented in the event of an outbreak were studied based on a literature review and simulations for forest recreation. To represent risk for the whole metropolitan France territory, three risk maps of the human population exposure to the pine processionary, the oak processionary and the brown‐tail moth were designed at municipality level. A multi‐criteria analysis was undertaken to characterize danger (urticating caterpillars) and vulnerability of human populations. Then, the municipalities were ranked according to their level of danger and vulnerability. As a result, municipalities have been classified into 5 danger classes and 5 vulnerability classes. Based on a risk matrix with levels of hazard (abscissa axis) and levels of vulnerability (ordinate axis), 5 levels of risk were finally defined and the 34,816 municipalities of metropolitan France were classified according to their level of risk
Numerical Simulation of a Microwave Applicator for the Treatment of Low-moisture Food
No full textInternational audienc
Élaboration de ressources pédagogiques numériques pour l'aide à l'apprentissage de l'Unité d'Enseignement Obstétrique Multi-espèces
No full textEn raison des difficultés rapportées par les étudiants dans l’UE 075 « Obstétrique multi-espèces » à Oniris VetAbroBio, des solutions sont recherchées. L’objectif : concevoir des ressources pédagogiques innovantes, utilisables en autonomie, qui apportent plus de diversité par rapport aux ressources déjà existantes et permettent un meilleur alignement pédagogique entre les méthodes d’enseignement de l’UE et l’évaluation. Deux types de ressources numériques ont été réalisées : 131 questions à choix multiples répartis dans 10 quiz sur le module « Maladies d’élevage abortives », créées à l’aide de l’outil « Test » de Connect. 3 scénarios à embranchements interactifs portant sur les thèmes des maladies d’élevage abortives et de la pathologie obstétricale, réalisés avec l’outil « H5P – Scénario d’embranchement ». Leur utilisation et leur réception ont été évaluées à partir des statistiques de consultation et d’un questionnaire étudiants. Les résultats montrent une forte appropriation des QCM, et une utilisation plus discrète, mais prometteuse, des scénarios d’embranchement. Les deux ressources ont reçu des retours globalement positifs de la part des étudiants sondés. Cette thèse met également en évidence aussi l’importance de l’ingénierie pédagogique dans la conception des parcours d’apprentissage, même en médecine vétérinaire
Le prolapsus utérin chez la vache : recensement des pratiques vétérinaires en France et évaluation terrain de l'efficacité de différentes méthodes pour la prévention des récidives
No full textUterine prolapse in cows is a postpartum obstetric emergency with multiple causes, including physiological and environmental factors. Vulvar closure is one treatment option, but its effectiveness to prevent recurrence is controversial. First, is present a literature review on the pathophysiology, risk factors, complications and therapeutic procedures to uterine prolapse, focusing on vulvar closure techniques. Is then present the results of a national survey of 201 veterinarians, which highlights wide heterogeneity among practices, influenced by context and individual habits. The R-prolapse survey allows estimation of the incidence of uterine prolapse and its recurrence in relation to different veterinary practices. Findings reveal Flessa pins are less used by the most experienced, younger veterinarians pay greater attention to analgesia, and recurrence rates are lower among respondents who favour interventions on recumbent cows. Finally, is present the results of a randomised prospective study (T-prolapse), conducted under field conditions, which assesses the impact of vulvar closure on recurrence and short-term mortality. Our findings show the absence of a closure device does not increase the risk of recurrence by up to 4 times compared to the use of Flessa pins. We have used a power analysis to calibrate future experiments to obtain greater accuracy. This work, which combines a literature review, an assessment of current practices and a field study, provides methodological and operational guidelines to inform treatment decisions. It paves the way for more powerful standardised multifactorial studies to optimise uterine prolapse management and prevent recurrence.Le prolapsus utérin chez la vache est une urgence obstétricale, à l’étiologie multifactorielle impliquant des facteurs physiologiques et environnementaux. Parmi les gestes de prise en charge, la fermeture vulvaire reste controversée quant à son efficacité à prévenir les récidives. Il est proposé d’abord une revue bibliographique sur la physiopathologie, les facteurs de risque, les complications et les approches thérapeutiques, avec un focus sur les techniques de fermeture vulvaire. Les résultats d’une enquête nationale auprès de 201 vétérinaires sont ensuite présentés, révélant une forte hétérogénéité des pratiques, influencées par le contexte d’exercice et les habitudes individuelles. Cette enquête (R-prolapse) permet d’estimer l’incidence du prolapsus et de ses récidives en lien avec les pratiques. Il est notable, par exemple, un moindre usage des épingles de Flessa chez les praticiens expérimentés, une attention accrue à l’analgésie chez les jeunes vétérinaires, et des taux plus faibles de récidives chez ceux privilégiant les interventions sur vache couchée. Enfin, une étude prospective randomisée (T-prolapse) conduite en clientèle est présentée pour évaluer l’impact de la fermeture vulvaire sur les récidives et la mortalité à court terme. Elle montre que l’absence de fermeture ne multiplie pas par plus de 4 le risque de récidive comparée à la pose d’épingles de Flessa. Une analyse de puissance a permis de calibrer de futures expérimentations pour une meilleure précision. Ce travail, associant revue, enquête et étude de terrain, fournit des repères pour guider la décision thérapeutique et ouvre la voie à des études multicentriques plus robustes
Effet de l'hyperglycémie maternelle et de la composition du lait associée sur la programmation de l'insulino-résistance de la descendance : étude expérimentale chez le rat
No full textInternational audienceIntroduction: Gestational diabetes (GDM) is associated with a risk of insulin resistance (IR) in offspring, but the benefits of breastfeeding on IR programming remain poorly understood. Objectives: To evaluate the impact of GDM milk composition on pancreatic β-cell maturation and hepatic homeostasis in offspring. Methods: GDM rats developed hyperglycemia during gestation in response to a high-fat, high-sugar (HFHS) diet, compared to euglycemic rats. This hyperglycemia was corrected or not postpartum depending on whether the HFHS diet was restricted to gestation or maintained until weaning. Cross-fostering at birth allowed the effects of gestation and lactation to be dissociated. The metabolome/lipidome of GDM colostrum and mature milk were characterized. The impact of milk on offspring was assessed throughout life and in adulthood in response to a high-calorie diet using oral glucose tolerance tests, euglycemic-hyperinsulinemic clamp, body composition measurements, gene expression analyses (pancreas, liver), and plasma metabolome analyses. Results: GDM milk was enriched with insulin regulators. GDM newborns showed hyperplasia and hypertrophy of β cells, combined with a specific plasma metabolome. At mid-lactation, those breastfed by mothers maintained in a hyperglycemic state showed fasting hyperglycemia and overexpression of pancreatic genes (NeuroD1, GLUT2, insulin). In adulthood, GDM offspring breastfed by control mothers showed impaired glucose tolerance (males) and reduced insulin sensitivity (females), associated with hepatic dysregulation (incomplete fatty acid oxidation (FAO), gluconeogenesis). Conversely, nursing by mothers whose hyperglycemia was corrected postpartum improved certain metabolic markers, particularly in females (complete FAO, reduced gluconeogenesis and lipogenesis). Conclusions: GDM milk modulates the development of IR in offspring in a sex-dependent manner, highlighting the importance of breastfeeding as a key period of metabolic programming and opening up avenues for targeted nutritional intervention
Influence du nutriome, exposome et microbiome du lait maternel sur la croissance précoce des nourrissons dans un contexte de prématurité
No full textInternational audienceIntroduction: The health benefits of breastfeeding for premature infants are clear, including improved postnatal growth, but the underlying mechanisms remain complex due to the rich composition of breast milk. Objective: To explore the interaction between breast milk nutrients, its microbiological components, and its level of exposure to environmental chemicals in relation to the growth of premature infants. Patients/Methods: In the prospective LACTACOL cohort (NCT014930), Z-scores for discharge weight and lean mass were measured in 137 exclusively breastfed premature infants. Breast milk was analyzed to characterize the nutriome, using targeted (amino acids and fatty acids and derivatives) and untargeted (lipidome) approaches, the exposome (persistent organic pollutants, POPs), and the microbiome (16s rRNA sequencing). A correlation analysis between the three components of breast milk followed by an e-learning analysis identified the molecular determinants of early growth in children.Results: Nutriome appeared to be the main contributor to postnatal growth in premature infants. Choline-containing lipids (sphingolipids, phosphatidylcholines, and plasmalogens) contributed positively to weight Z-score. Nervonic acid-enriched sphingomyelin was positively associated with lean mass Z-score, in contrast to oxylipins. The exposome showed complex effects: the dioxin-like compound 1,2,3,7,8-PeCDD had a negative impact on weight, while polychlorinated biphenyl 123 positively influenced weight and lean mass gain. Brominated flame retardants were associated with a decrease in lean mass Z-score. Despite a minor impact, the microbiome varied with POP levels and postnatal growth tertiles, highlighting co-dependencies between milk components. Conclusions: This pilot study provides new evidence on the interaction of the nutriome, exposome, and microbiome of breast milk and their joint influence on the early development of premature infants
les enjeux organisationnels et managériaux comme leviers de performance industrielle : étude de deux diagnostics menés en milieu industriel
No full textThis thesis, conducted as part of an internship within the consulting firm Quaternaire, is based on two industrial diagnostic assignments carried out in the pharmaceutical and agri-food sectors. The objective was not to directly measure performance, but rather to demonstrate that organizational and managerial issues are genuine levers for sustainable performance improvements. The diagnostic emerges here as a tool for awareness: it highlights often implicit dysfunctions, combines factual data with employee' perceptions, and establishes a share understanding of the organizational reality. More than a simple assessment, it paves the way for a dynamic of transformation by making key performance levers visible. The cross-analysis of both missions reveals several findings. Managerial maturity is crucial to give meaning and mobilize teams. Organizational clarity directly conditions operational fluidity, while vertical alignment between strategy and the shop floor proves essential to channel collective efforts. additional factors also play a decisive role : the effective use of standards and indicators, croos-functional cooperation, the safeguarding of critical skills, and the active listening of employees. Ultimately, this thesis demonstrates that industrial performance cannot be reduced to technical indicators alone : it ptimarily relies on the quality of management and organization, witch the diagnostic helps to bring to light in order to guide companies toward sustainable transformation.Ce mémoire réalisé dans le cadre d'un stage au sein de la société de conseil Quaternaire, s'appuie sur deux missions de diagnostic industriel menés en milieu pharmaceutique et agroalimentaire. L'objectif n'était pas de mesurer directement la performance, mais de montrer que les enjeux organisationnels et managériaux constituent de véritables leviers pour améliorer durablement la performance des entreprises. Le diagnostic apparaît ici comme un outil de prise de conscience : il permet de révéler des dysfonctionnements parfois implicites, de croiser données factuelles et perceptions du terrain, et de créer une lecture commune de la réalité organisationnelle. Plus qu'un état des lieux, il ouvre la voie à une dynamique de transformation en rendant visibles les leviers de progrès. L'analyse croisée des deux missions met en évidence plusieurs constats. La maturité managériale se révèle essentielle pour donner du sens et mobiliser les équipes. La clarté organisationnelle conditionne directement la fluidité des opérations, tandis que la cohérence verticale entre stratégie et terrain s'avère déterminante pour aligner les efforts. D'autres facteurs clés ressortent également : l'animation des standards et indicateurs, la coopération interservices, la sécurisation des compétences et l'écoute des collaborateurs. En définitive, ce mémoire illustre que la performance industrielle ne se limite pas aux indicateurs techniques : elle repose avant tout sur la qualité du management et de l'organisation, que le diagnostic permet de mettre en lumière pour engager les entreprises vers une transformation durable
Description tomodensitométrique des noeuds lymphatiques axillaires accessoires chez le chat
No full textLes nœuds lymphatiques axillaires accessoires du chat sont peu décrits dans la littérature, malgré leur rôle clé dans le drainage lymphatique de certaines régions (paroi thoracique, membre thoracique, tissu mammaire). Afin de mieux comprendre leur aspect physiologique, cette thèse propose une étude rétrospective descriptive tomodensitométrique de ces structures dans l’espèce féline. Une analyse rétrospective a été menée à partir de 47 scanners thoraciques de chats ne présentant pas d’atteinte connue des territoires drainés par le lymphocentre axillaire. Pour chaque individu, les nœuds lymphatiques axillaires accessoires ont été localisés et caractérisés selon leur nombre, leur position, leur forme, leur volume, leur atténuation et leur rehaussement après contraste. L’étude met en évidence une grande variabilité interindividuelle, tant dans la présence que dans la morphologie de ces nœuds lymphatiques. Leur taille réduite, leur proximité avec la graisse, ainsi que les limites de résolution spatiale du scanner, rendent leur identification délicate. Cependant, cette étude confirme que ces structures sont détectables de façon plus fréquente chez les chats de poids élevé, sans association significative avec l’âge ou le sexe, avec un nombre de structures observées allant de zéro à trois par côté. Ce travail fournit une première base de référence pour l’aspect normal des nœuds lymphatiques axillaires accessoires en tomodensitométrie chez le chat. Il souligne l’intérêt d’une meilleure connaissance des images physiologiques pour une meilleure interprétation de l’aspect de ces structures, en particulier lors d’affection localisée dans leur aire de drainage