HAL Université de Tours
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Gonadotropin secretion and ovarian response of KISS1 knockout gilts treated with hormone analogs activating the hypothalamic–pituitary-gonadal axis
No full textInternational audienceKisspeptin knockout (KISS1−/−) pigs exhibit hypogonadotropic hypogonadism. Hormone analogs targeting different levels of the hypothalamic–pituitary-gonad axis were used to characterize the secretion of reproductive hormones (LH, luteinizing hormone; and follicle-stimulating hormone, FSH) and ovarian responses (estradiol and progesterone) in KISS1−/− gilts. Uteri and ovaries were collected from KISS1+/+ and KISS1−/− gilts to confirm ovulatory outcomes. Pulses of LH and FSH were observed in KISS1−/− gilts that differed (P < 0.05) in amplitude and nadir from pulses in wild-type KISS1+/+ and KISS1+/− gilts. A neurokinin B (NKB) agonist stimulated LH but not FSH in wild-type gilts, whereas NKB affected neither LH nor FSH in KISS1−/− gilts. The kisspeptin receptor agonist, C6, stimulated LH secretion in wild-type gilts but not in KISS1−/− gilts (P < 0.05). Secretion of LH in KISS1−/− gilts depends on the dose and frequency of gonadotropin-releasing hormone (GnRH). Priming with estradiol-17β and GnRH before pregnant mare serum gonadotropin and human chorionic gonadotropin treatment resulted in luteal structures on the ovary of KISS1−/− gilts, though ovulation rate was less (P < 0.05) than KISS1+/+ gilts. This is the first report showing NKB regulation of LH secretion in swine. It is confirmed that a single copy of the KISS1 allele in gilts confers normal gonadotropin secretion following stimulation with NKB, kisspeptin, and GnRH analogs. The sustained activation of the kisspeptin receptor by C6 generated long-lasting LH secretion in gilts to induce ovulation. Ovulation in KISS1−/− gilts is possible, but treatments need optimization to maximize ovulation rate
Finite element modeling of buckle defects formation during RTM preforming of dry woven reinforcements
No full textInternational audienceAbstract. Mesoscopic defects, such as buckles and yarn sliding, arise in dry woven reinforcements during the preforming step of processes like the Resin Transfer Molding process. To study these defects, the LaMé laboratory developed an experimental device based on the Pullout test, which replicates the conditions leading to defect formation but does not fully explain the underlying mechanics. To address this, a Finite Element Model (FEM) is proposed to complement experimental data by providing detailed insights into stress, strain, and friction. While the model offers preliminary predictions of buckle defects, a full identification of the remaining parameters, including friction and those related to the fixed jaws, is essential for accurate parametric studies on their formation
Physico-mechanical characterization of 3D-printed PLGA for patient-specific resorbable implants in craniofacial surgery
No full textInternational audiencePatient-specific implant (PSI) has optimized the management for a wide range of complex craniofacial deformity over the past years by increasing the accuracy of surgical procedures and lowering the operating time. In hypertelorism (HTO) surgery particularly, the orbital bone repositioning is nowadays guided by patient-specific bone fixation plates that are usually made from non-resorbable alloplastic material (e.g., titanium). Developing resorbable personalized plates could be a relevant alternative to overcome the well-known drawbacks of titanium plates such as infection, exposure or even the lack of bone growth which is detrimental in pediatric patients. This study investigated the mechanical and structural characteristics of poly(lactic-co-glycolic acid) (PLGA) PSI as resorbable materials for HTO surgery. We assessed the feasibility of printing PLGA PSI by Fused Deposition Modeling additive manufacturing (FDM). The geometrical and the mechanical properties of the 3D-printed device were compared with standard resorbable plates and analyzed after sterilization process (i.e., hydrogen peroxide gas plasma). The Young’s modulus was greater than the standard resorbable plates while a decrease of 36% (p = 0.004) after the sterilization was observed. The sterilization also induced a plate deformation with an increase of 0.27 mm in Z-axis and a decrease of 0.8 mm in Y-axis due to annealing effect. Compared to the design, the PLGA PSI were successfully 3D-printed with a maximum deviation of 0.1 mm, making our custom-made plate promising for personalized craniofacial applications. Further investigations on the sterilization process must be considered in view of its mechanical and structural impact on resorbable PSI
Effet de l’âge sur la mémoire de l’action : quel est le rôle de la cinématique ?
No full textInternational audienc
Perinatal exposure to the autism-linked metabolite p-Cresol has limited impact on early development in mice but lasting effects on adult social behavior
No full textInternational audienceEnvironmental exposures during pregnancy are increasingly recognized as significant risk factors for the offspring health. Perinatal exposure to environmental toxins, including p-Cresol, may disrupt essential physiological processes during critical developmental windows. The perinatal period is particularly critical for neurodevelopment, making the brain particularly vulnerable to external toxins that can impair neural circuitry and increase the risk of behavioral and neuropsychiatric disorders later in life. p-Cresol, a microbial metabolite produced by the human microbiota and through the bacterial decomposition of organic matter, is also released in exhaust fumes and widely used in chemical manufacturing. Elevated levels of p-Cresol have been consistently observed in patients with autism spectrum disorders (ASD), yet, its developmental toxicity and its impact on ASD-related behaviors remain to be determined. In this study, we exposed pregnant mice (C57BL/6J) to p-Cresol via drinking water from mid-gestation, through lactation, and until weaning, mimicking potential patterns of human exposure during pregnancy and early infancy. Our findings indicated that while perinatal p-Cresol exposure did not affect gestational outcomes, postnatal growth, developmental milestones, or sensorimotor reflexes, it resulted in marked social deficits and stereotyped behaviors in adult males and females offspring-which are core behavioral phenotypes associated with ASD. These results suggest that p-Cresol exposure selectively induces ASD-like behaviors, without broadly impairing early development. Our findings emphasize the need for future epidemiological studies to quantify p-Cresol exposure during pregnancy and early childhood, and to evaluate its potential association with social behavior impairments in children. This research provides a foundation for understanding how environmental factors, such as p-Cresol, may contribute to social impairments and neurodevelopmental disorders in the broader population.</div
Tremblay-en-France (93), 2 rue Jules Guesde (Lot B). Des espaces à vocation agricole ?
No full text2 VOLUMESLes fouilles menées sur le site du 2 rue Jules Guesde à Tremblay-en-France (93), ont été réalisées par le bureau d'études Éveha sous la responsabilité de T.-A. Gérardin. Elles interviennent dans le cadre d’un projet d'aménagement (Fnap) pour le compte de M. Mechmache, propriétaire du terrain. Ce chantier de 989 m² a livré 307 faits archéologiques. Les investigations archéologiques ont permis de mettre au jour des vestiges datant de plusieurs plages chronologiques, s’échelonnant de la Protohistoire à la période moderne. L’essentiel des structures peut être considéré comme excavé puisqu’il s’agit de trous de poteau, de fossés, de fosses et de silos. Le réseau fossoyé est dense ; il répond pour une part aux parcellaires identifiés sur les deux terrains mitoyens, fouillés précédemment : le site du 4 au 10 rue Jules Guesde (Berthier 2022) au nord- ouest, et la fouille rue Guesde / rue du Cimetière (Gonçalvès-Buissart 2012) au sud- est. Il faut mentionner la découverte de nombreux trous de poteau et la présence de structures comme des silos, un cellier et deux puits. Cet inventaire doit être mis en perspective des découvertes d’artefacts qui témoignent d’une longue occupation. Enfin, les deux structures bâties sont des faits contemporains
Cultural Heritage
No full textArticle du dossier «European Research Challenges: Some common scientific perspectives from CNR, CNRS and CSIC»International audienceCultural Heritage permeates every aspect of our contemporary society, manifesting in physical spaces, intangible traditions, and virtual realms. Far from being merely artefacts from the past, Cultural Heritage represents a living, dynamic framework that shapes our understanding of who we are and guides our path forward. The importance of Cultural Heritage research has never been more critical than in our current historical context.Heritage Science, encompassing all forms of scientific inquiry into human works and the combined works of nature and humans that are of value to people1, offers critical thinking and human-centred perspectives, providing essential tools in an age of artificial intelligence and automated decision-making. It supplies an ethical framework for social responsibility, offering historical context for contemporary challenges. It reinforces democratic values and social cohesion through insights into the evolution of social structures and governance systems. It enhances the understanding, preservation, sustainable use and management of tangible and intangible heritage.The field promotes a long-term vision that is crucial for informed decisions about our collective future, while serving as a transdisciplinary bridge connecting the humanities and sciences in a comprehensive approach to complex challenges
Compte rendu de: Marco COPPOLARO, Giulia MURACE, Gianluca PETRONE (éd.), Le arti e gli artisti nella rete della diplomazia pontificia, Rome, Gangemi Editore, 2023. À paraître en mai 2026 dans la Revue d’histoire ecclésiastique / Louvain Journal of Church History
No full textFrench Lexicography
No full textInternational audienceThis article explores the history and evolution of French lexicography, from its early beginnings in the medieval glossaries to the foundational works of the 17th century, such as the first monolingual French dictionaries.It traces the creation of pivotal lexicographic models, including those by Pierre Richelet, Antoine Furetière, and the French Academy, which laid the groundwork for modern dictionaries. The article also discusses the rise of digital lexicography in the 21st century, emphasizing its continuous development and adaptation, including the ongoing work of the ninth edition of theDictionnaire de l’Académie française
