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Lieux et modes d’existence du savoir expérientiel : savoirs incorporés, savoirs situés
No full textInternational audienceCe dossier interroge les théories et pratiques associées à l’usage du terme « savoirs expérientiels » à partir de leurs lieux et modes d’existence. Problématiser les savoirs expérientiels à partir de leurs modes d’existence consiste à déplacer la focale analytique d’une définition des savoirs vers la description des conditions et modalités de leur instauration. Un tel déplacement ouvre sur une conception de l’expérience non plus comme propre à l’individu mais comme ce qui se joue dans la rencontre entre les strates du vécu sensible, cognitif et perceptif qui caractérisent les savoirs expérientiels et les propriétés des situations où de tels savoirs sont effectivement engendrés et/ou mobilisés. Au moins quatre traits constitutifs du mode d’existence des savoirs expérientiels ont été identifiés : leur degré de formalisation (i.e. leur mise en forme) ; les types de cadrage (sense-making frames, participatory frames, narrative frames) ; la codépendance entre catégories de savoirs (tacites, formels, incarnés, etc.) ; les principes d’intégration (faire tenir ensemble les éléments expérientiels) et de logique dispositive (organisation et orientation propre aux situations)
Traditional Cosmeceutical and Therapeutic Uses of Shea Butter (Vitellaria paradoxa) in the Maritime Region of Togo
No full textInternational audienceIntroduction: Shea butter (Vitellaria paradoxa), revered as "women's gold," is a vital socio-economic and cultural resource in Togo. However, the associated traditional knowledge, transmitted orally, is poorly documented and threatened by urbanization and ecological pressures. This study documents and analyzes the traditional cosmeceutical and therapeutic applications of shea butter in Togo's Maritime region to preserve this intangible heritage and explore its potential for sustainable development. Materials and Methods: An ethnobotanical survey was conducted from September to November 2024, involving semi-structured interviews with 210 women (resellers, users, beauticians) across eight prefectures. Data were analyzed using thematic analysis and citation frequency calculations. A targeted literature review was performed to identify articles that explain the therapeutic and cosmetological mechanisms of our research finding. Results: Results highlight a dual function: cosmetic, dominated by skin hydration (92.9% of citations), and therapeutic, led by the relief of muscular and joint pain (85.6%). The investigation also documented the medicinal uses of the tree's bark, leaves, and roots, confirming a holistic ethnobotanical knowledge. By corroborating these traditional cosmetic and therapeutic practices with scientific literature, the study validates their biochemical basis, particularly the anti-inflammatory and regenerative properties of the butter's rich unsaponifiable fraction. Conclusion: By comparing this traditional knowledge with scientific literature, the study validates the biochemical basis of these ancestral practices, particularly the anti-inflammatory and regenerative role of the butter's rich unsaponifiable fraction. While insightful, the study's qualitative design and snowball sampling limit the generalizability of the findings. The study underscores the necessity of preserving this threatened heritage and promoting its sustainable development through value chains that respect local knowledge
Domain‐Wall Driven Suppression of Thermal Conductivity in a Ferroelectric Polycrystal
No full textInternational audienceA common strategy for reducing the thermal conductivity of polycrystalline systems is to increase the number of grain boundaries. Indeed, grain boundaries enhance the probability of phonon scattering events, which has been applied to control the thermal transport in a wide range of materials, including hard metals, diamond, oxides, and two-dimensional (2D) systems such as graphene. Here, the opposite behavior in improper ferroelectric ErMnO 3 polycrystals is reported, where the thermal conductivity decreases with increasing grain size. This unusual relationship between heat transport and microstructure is attributed to phonon scattering at ferroelectric domain walls. The domain walls are more densely packed in larger grains, leading to an inversion of the classical grain-boundary-dominated transport behavior. The findings open additional avenues for microstructural engineering of materials for thermoelectric and thermal management applications, enabling simultaneous control over mechanical, electronic, and thermal properties
Identification, occurrence and prevention of aspartimide-related byproducts in chemical protein synthesis
No full textInternational audienceFormation of a five-membered ring aspartimide through the attack of a backbone amide to the side chain of aspartate and asparagine residues is a long-known side-reaction in solid phase peptide synthesis, and is also associated with in vivo protein ageing and instability of purified proteins. Conversely, its possible occurrence during chemical ligation-based protein synthesis, in particular when using the gold-standard reaction NCL (native chemical ligation), is dubious. We herein report a systematic study which demonstrates that the prevalence of this side-reaction may have been overlooked, due to the difficulty to identify it through standard HPLC analytical methods, but also the in situ conversion of aspartimide into other byproducts, having the same molecular mass as the parent aspartate residue. We show that the formation of aspartimide and derived byproducts can be limited by adopting "good NCL practices", which involve restricting the ligation temperature and reaction times, as well as replacing the commonly used phosphate buffer with HEPES. However, the efficiency of such precautions is expected to vary considerably depending on the sequence of the target protein, and the amount of byproducts is expected to grow with the length of the target protein, as a result of the number of NCL reactions and potential aspartimide hotspots. To overcome such limitations, we developed a novel straightforward and potentially generally applicable methodology based on the temporary protection of the backbone nitrogen by a 2-(4-aminobutanoyloxy)-4-methoxybenzyl (GABA-Hmb) group. This strategy was validated by the byproduct-free synthesis of SUMO-2 and a SUMOylated peptide mimic.Scheme 1 Native Chemical Ligation (NCL).</div
Bioluminescence Resonance Energy Transfer: A Powerful Technique in Neuropharmacology for Discovering New Ligands of G Protein-Coupled Receptors
No full textMasterThe Bioluminescence Resonance Energy Transfer (BRET) is a proximity-based assay used to study protein-protein interactions in living cells. The principle behind BRET involves resonance transfer of energy between bioluminescent enzymes and a fluorescent acceptors, resulting in measurable signals that indicate specific molecular interactions. BRET has been widely adopted in drug discovery as a high-throughput screening method to investigate the behavior of signaling proteins, such as G protein-coupled receptors (GPCRs). Due to its ability to operate under physiological conditions, BRET is a highly sensitive and well-suited tool for real-time, dynamic studies regarding diverse signaling pathways, their downstream messengers, receptor internalization and more
Synergistic pathogenicity between Herpesvirus and Vibrio aestuarianus in killing juvenile oysters during spring in natural conditions
No full textInternational audienceYoung oysters of Pacific oyster Magallana (Crassostrea) gigas are regularly impacted by summer mortalities since 2008, caused by the infection by the Ostreid herpesvirus 1 (OsHV-1) when seawater temperature increases in summer. Adult oysters rather suffer from a vibriosis caused by the bacterial primary pathogen Vibrio aestuarianus francensis. Although these diseases are now well described, little is known about their contribution and possible synergy in natural mortality events of juvenile oysters. Using an in-situ approach conducted in the Thau lagoon, we investigated the potential implication of Vibrio aestuarianus in the juvenile oyster's mortality, as well as the virus OsHV-1, throughout a large sampling period from winter to late summer, after the mortality event. We further determined their respective effects on the microbial abundance and diversity on alive and moribund oysters. We demonstrated that microbiomes are dynamic throughout seasons and tend to become more similar in spring with a dominance of Mycoplasmataceae in alive oysters. Surprisingly, our data highlighted the prevalence and high loads of Vibrio aestuarianus in all moribund oysters. In contrast with the literature, we found that the microbial communities of moribund juvenile oysters were significantly influenced by both Vibrio aestuarianus and the virus OsHV-1. The moribund bacterial indicators were detected in abundance during mortalities in the surrounding environment of oyster farms and further (700 m far). These results highlight the connectivity between the different compartments of the lagoon and raise questions about the potential spread of the primary pathogen Vibrio aestuarianus from adult to juvenile oysters in farming areas located in lagoons
A Concert for the Centenary of Ireland’s Partial Independence: Explorations in Arts-Practice
No full textInternational audienceThis chapter examines the new possibilities arising from research-creation (sometimes called “arts-practice research” or “practice-based research”) in Irish studies through the example of Siansach 32 / Symphony 32, a new musical composition for symphony orchestra and Irish instruments celebrating the centenary of Ireland’s partial independence in 2022. A brief presentation of the origins and aims of the project is given here, followed by the description of the different stages of the project, of the new horizons offered by arts-practice research and by a presentation of its actual production in Limerick in July 2022. This paper also demonstrates how fertile fusions between arts – including more specifically music in this case-study – and science can be, through the mediation of culture. Finally, it shows research-creation can contribute to the development of Irish studies in Europe and beyond.Ce chapitre examine les nouvelles possibilités offertes par la recherche-création (parfois appelée « recherche sur les pratiques artistiques » ou « recherche fondée sur la pratique ») dans les études irlandaises à travers l’exemple de Siansach 32 / Symphony 32, une nouvelle composition musicale pour orchestre symphonique et instruments irlandais célébrant le centenaire de l’indépendance partielle de l’Irlande en 2022. Une brève présentation des origines et des objectifs du projet est proposée ici, suivie d’une description des différentes étapes du projet, des nouveaux horizons offerts par la recherche-création et d’une présentation de sa production effective à Limerick en juillet 2022. Cette présentation montre à quel point les pratiques de fusion entre les arts – y compris plus spécifiquement la musique dans ce qui relève de la présente étude de cas – et la science peuvent être fécondes, mettant en valeur la médiation assurée par la culture. Enfin, le chapitre montre que la recherche-création peut contribuer au développement des études irlandaises en Europe et au-delà
The crazy ovary 2: a tribute to Ken McNatty
No full textInternational audienceIn 2021, Ken McNatty, Danielle Monniaux, and I published a review essay illustrating how ovarian folliculogenesis can sometimes be bizarre, amazing, or even almost incomprehensible. Examples included the mechanisms underlying intra- and inter-species differences in ovulation rates; the possibility of awakening human primordial follicles in vitro, maturing and fertilizing them to produce viable offspring; and a model in which inactivation of a single oocyte gene results in sterile mice with follicular growth blocked at the primary stage but normal steroid cyclicity maintained. The aim of this second essay is to present further examples of the extraordinary diversity of ovarian function across animal species and, where possible, to propose hypotheses that may explain them. These concern: 1) the presence of oogonial stem cells in the ovaries of invertebrates and non-mammalian vertebrates, and their very probable absence in mammals; 2) the many and varied strategies of ovarian development and oogenesis in teleosts; 3)the metabolic dialog between cumulus cells and oocytes across mammalian species; 4) the presence of numerous germline genes, specifically or even exclusively expressed in the mammalian oocyte, whose invalidation has no phenotypic consequence on fertility in the mouse; 5) the unique features of ovarian function in the dog, particularly the frequent presence of polyovular follicles and the distinctive mode of post-ovulatory oocyte maturation; and 6) the absence of an intra-ovarian dominance factor in mono-ovulating species, disproving an old hypothesis: the selection of a single follicle is instead due to a succession of negative and then positive feedback between follicles and the hypothalamic–pituitary axis. This essay is also a final tribute to Ken McNatty, who liked to say that the ovary could be crazy
Evaluation of clindamycin use in bone and joint infections: is monotherapy a safe option? A monocentric observational study 2014–19
No full textPublication on behalf of the CRIOGO local group : Laura Chaufour, Geoffroy Dubois De Montmarin, Marion Lacasse, Marie-Frédérique Lartigue, Adrien Lemaignen, Louis-Romée Le Nail, Denis Mulleman and Vianney Tuloup.International audienceBackground: Selecting an optimal antibiotic regimen for bone and joint infections (BJIs) is challenging due to limited high-quality evidence. Although clindamycin is widely used as an alternative treatment for susceptible microorganisms in combination therapy, its use as monotherapy is increasing. This study aimed to evaluate the efficacy and safety of clindamycin monotherapy for BJI treatment.Methods: A monocentric observational study was conducted using data from the Reference Centre for complex BJI at our tertiary university hospital between 2014 and 2019. All adult patients with microbiologically confirmed BJI receiving clindamycin after a multidisciplinary meeting were included. Patients infected with clindamycin non-susceptible strains were excluded. Treatment failure was defined as relapse, treatment change or death from any cause within 1 year. Associations between monotherapy and treatment failure were assessed using multivariate logistic regression and inverse probability of treatment weighting (IPTW) analysis to adjust for the propensity to receive monotherapy.Results: A total of 137 patients were included, of whom 88 received clindamycin monotherapy. Overall, 41/137 treatment failures were observed (16/88 in the monotherapy group, 25/49 in the combination group). Monotherapy was associated with fewer failures in both multivariate (OR = 0.18; 95% CI, 0.07-0.46; P < 0.001) and IPTW-adjusted models (OR = 0.36; 95% CI, 0.17-0.76; P = 0.008). Patients treated with monotherapy presented with milder infections, less fever and lower Charlson comorbidity scores, with significantly lower baseline C-reactive protein levels (102.6 versus 65.7 mg/L; P = 0.006). Fewer adverse events were reported in the monotherapy group (4/88 versus 8/49, P = 0.04).Conclusions: Clindamycin monotherapy appears to be a reliable and safe therapeutic option for selected patients with less severe BJI