Oskar Bordeaux
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PLoS Biol
Get PDFIn the glucose-free environment of the midgut of the tsetse fly vector, the procyclic forms of Trypanosoma brucei primarily consume proline to feed its central carbon and energy metabolism. In this context, the parasite produces through gluconeogenesis, glucose 6-phosphate (G6P), the precursor of essential metabolic pathways, from proline catabolism. We show here that the parasite uses three different enzymes to perform the key gluconeogenic reaction producing fructose 6-phosphate (F6P) from fructose 1,6-bisphosphate, (i) fructose-1,6-bisphosphatase (FBPase), the canonical enzyme performing this reaction, (ii) sedoheptulose-1,7-bisphosphatase (SBPase), and (iii) more surprisingly ATP-dependent phosphofructokinase (PFK), an enzyme considered to irreversibly catalyze the opposite reaction involved in glycolysis. These three enzymes, as well as six other glycolytic/gluconeogenic enzymes, are located in peroxisome-related organelles, named glycosomes. Incorporation of 13C-enriched glycerol (a more effective alternative to proline for monitoring gluconeogenic activity) into F6P and G6P was more affected in the PFK null mutant than in the FBPase null mutant, suggesting the PFK contributes at least as much as FBPase to gluconeogenesis. We also showed that glucose deprivation did not affect the quantities of PFK substrates and products, whereas an approximately 500-fold increase in the substrate/product ratio was expected for PFK to carry out the gluconeogenic reaction. In conclusion, we show for the first time that ATP-dependent PFK can function in vivo in the gluconeogenic direction, even in the presence of FBPase activity. This particular feature, which precludes loss of ATP through a futile cycle involving PFK and FBPase working simultaneously in the glycolytic and gluconeogenic directions, respectively, is possibly due to the supramolecular organization of the metabolic pathway within glycosomes to overcome thermodynamic barriers through metabolic channeling
Neurochirurgie
Get PDFOBJECTIVE: To develop a multidisciplinary French framework addressing neurosurgical management in the initial phase of traumatic brain injury (TBI) in adults and children. DESIGN: A panel of 29 experts was formed at the request of the French Society of Neurosurgery (SFNC), with the participation of the French Society of Pediatric Neurosurgery (SFNCP), French Society of Private-Practice Neurosurgeons (SFNCL), French-Speaking Neurocritical Care and Neuro-Anesthesiology Society (ANARLF), French Society of Anesthesia, Critical Care and Perioperative Medicine (SFAR), French-Speaking Pediatric Emergency and Intensive Care Group (GFRUP), French Society of Neuroradiology (SFNR), French-Speaking Infectious Diseases Society (SPILF), and the French Society of Physical Medicine and Rehabilitation (SOFMER). METHODS: Questions were formulated using the PICO (Patients, Intervention, Comparison, Outcome) format, grouped into 7 categories: 1. Factors of poor prognosis, 2. Extradural hematoma, 3. Acute subdural hematoma, 4. Skull-base fracture and dural tear, 5. Penetrating traumatic brain injury, 6. Post-traumatic cerebrospinal fluid disorder, and 7. Pediatric specificities. RESULTS: Synthesis by the experts and application of the GRADE® method resulted in the formulation of 45 recommendations. Strong consensus was reached for all recommendations at the first round of rating, CONCLUSION: There was a strong consensus among the experts on important interdisciplinary recommendations to improve the neurosurgical management of patients with TBI
Paternal involvement and children's internalization of gender roles in early childhood
No full textObjective: This study investigates the effects of paternal involvement on the frequency of gender-incongruent activities in children's play at age 2. Background: Recent research suggests that paternal involvement is associated with more gender egalitarian attitudes in children and a more egalitarian distribution of housework tasks between sons and daughters. Although previous studies have tested the effects of paternal involvement on teenage children, the process of internalization of gender norms and roles in early childhood has not yet been investigated. Method: Analyses are based on the French Elfe cohort with information at age 2 for 11,564 children born in 2011. Multivariate linear and multinomial logistic regression models were run separately for sons and daughters. Results: Paternal involvement in early childhood was associated with more frequent gender-incongruent activities in boys' but not in girls' play at age 2. The effect of paternal involvement further varied depending on the type of involvement: involvement in housework tasks and childcare was associated with more gender-incongruent activities for sons but paternal participation in children's play increased the frequency of activities gender-typed as masculine, independently of the child's sex. Conclusion: Paternal involvement in housework and childcare in early childhood shapes gender-typed activities in toddlers' play for sons but not for daughters. It contributes to "undoing gender" in play activities for boys and, in doing so, narrows the gender gap in children's play
Int. J. Intercult. Rel.
No full textThe paper discusses the importance of considering diversity in public institutions and the need for intercultural training for practitioners. It emphasizes the psychological characteristics essential for dealing with diversity, focusing on multicultural personality traits, host community acculturation orientations, and adult attachment. The study aims to assess these psychological characteristics in future social workers and occupational therapists across three settings (France, n=273, Quebec, n=63, and Switzerland, n=66) before their integration internships. It is expected that certain personality profiles will be associated with favorable acculturation orientations and secure attachment, while others will be linked to less welcoming acculturation orientations and insecure attachment. Participants completed the Multicultural Personality Questionnaire (MPQF), the Host Community Acculturation Scale (HCAS) and the Revised Adult Attachment Scale (R-AAS). Analysis methods include hierarchical cluster analysis on the MPQF to identify intercultural personality profiles and subsequent ANOVAs to explore associations with acculturation orientations and attachment dimensions. Four multicultural personality profiles are identified: considerate (open and attentive), adaptive (handling new situations well), maladaptive (low scores on all traits, uncomfortable in intercultural situations), and reticent (reserved in intercultural encounters). Specific profiles align with distinct acculturation orientations, such as the considerate profile with a rejection of exclusion. Additionally, the adaptive profile displays consistently low anxiety levels. The study highlights that a significant proportion of students (40% to 60%) may lack competence in intercultural contexts. It questions the adequacy of intercultural training in curricula and emphasizes the need for further research on the impact of such training on students’ competence in handling diversity
From the primitive mentality to the civilization of capitalism: Joseph Schumpeter, reader of Lucien Lévy-Bruhl
No full textThis article explores the scientific connection between Lucien Lévy-Bruhl’s anthropological framework and Joseph Schumpeter’s theory of capitalism. Schumpeter incorporates Lévy-Bruhl’s concepts of “primitive mentality” and its contrast to “logical mentality” into his analysis of the cultural dimensions of capitalism. When characterising the “civilization” of capitalism, Schumpeter emphasises its “rationalistic” and “logical” aspects, drawing from Lévy-Bruhl’s depiction of “logical mentality.” Furthermore, Schumpeter adopts Lévy-Bruhl’s methodological approach, which posits that the mental structures of a society are shaped by its socio-economic organisation
Retour sur un phénomène en "euses" (1971-1983=
No full textDes "Allumeuses" aux "Voyeuses" (par ordre alphabétique) ou des "Ravageuses" aux "Stoppeuses" (par ordre chronologique), les titres en « euses » se sont multipliés aux frontons des salles de cinéma. La production française a aussi cédé à la mode. Il s’agit d’abord d’analyser et de comprendre cet engouement, le sens de ce recours généralisé au pluriel pour désigner les personnages féminins au moment où la société est traversée par les mouvements féministes qui défendent, au contraire, la singularité de chaque femme. Il s’agit ensuite de présenter ces films français au pluriel féminisé en tentant une classification en fonction de ce que ces titres désignent (ou pas) dans le film concerné
Research and implementation of a fast-charging methodology for lithium-ion batteries under bottom and dual cooling configurations
No full textThis study addresses the critical challenge of fast-charging lithium-ion batteries for electric vehicles while maintaining safety and longevity. Two optimized charging profiles (MSCC and spline-based) are developed to minimize charging time while respecting voltage and temperature constraints. The research utilizes both cell and battery module models to solve this optimization problem. A key innovation is the investigation of dual-side cooling, employing both top and bottom cooling plates simultaneously. This novel thermal management approach significantly reduces thermal gradients and promotes uniform temperature distribution across battery cells, enhancing the overall charging process. The study also explores modifications to cell internal connections to improve performance. The optimized cooling configuration demonstrates substantial improvements, reducing charging time by 30 % compared to the test bench configuration and decreasing thermal gradients by 63 % relative to high-convection bottom cooling. These results underscore the importance of advanced thermal management in fast-charging applications. Additionally, the research proposes an implementation solution to address discrepancies between the model used for profile optimization and the actual battery characteristics. This adaptive approach ensures the optimal charging profiles remain effective when applied to real-world systems. By integrating optimized charging profiles, efficient cooling systems, and sophisticated modelling techniques, this study provides valuable insights for achieving faster and safer charging of lithium-ion batteries. The findings have significant implications for advancing electric vehicle technologies and addressing key barriers to widespread EV adoption
Elusive tropical forest canopy diversity revealed through environmental DNA contained in rainwater
No full textExploring the biodiversity hidden in tropical rainforests canopies represents a major frontier in biodiversity research yet remains challenging. Environmental DNA (eDNA) can revolutionize this field as it did already in various ecosystems. Here, we test the hypothesis that eDNA contained in canopy throughfall could be used to monitor this elusive diversity and detect anthropogenic disturbance. Using custom-made, low-cost rain collectors, we sampled rainwash eDNA in a mature Amazonian forest and a nearby tree plantation. We successfully detected eDNA from tropical woody and epiphyte plants, vertebrates (mammals, birds, and amphibians), and insects (e.g., mosquitoes, ants, and beetles). The taxonomic composition and diversity reflected disturbance, with significantly lower diversity in the plantation. Crucially, rainwash eDNA integrated biodiversity over a 10-day period in passive collectors and provided a local signature. This approach has thus potential for establishing a cost-effective monitoring system for tropical moist forest canopies, applicable in impact assessments and sustainable management.CEnter of the study of Biodiversity in AmazoniaTowards a Unified theory of biotic Interactions: the roLe of environmenta
Selva, bambú y sistemas agroforestales para la adaptación al cambio climático en fincas cafeteras de Colombia
No full textEn Colombie, c’est dans la région des Andes que l’on trouve le plus grand nombre deforêts secondaires, une région où la culture du café est également très répandue. Uneanalyse a été réalisée pour évaluer la forêt, le bambou et l’agroforesterie dans les fermes des familles productrices de café en tant que stratégie pour la transition agroécologique. La recherche a été menée dans trois municipalités du plateau de Popayán, dans le département de Cauca, au sudouestde la Colombie. La présence de forêts, de bambous et de systèmes agroforestiers a été examinée à l’aide d’outils qualitatifs et quantitatifs, et en utilisant la méthodologie Shade Tree Advice pour déterminerla fourniture de services écosystémiques. Les résultats ont confirmé que les fermes évaluées sont des lieux habités par des familles paysannes avec une utilisation diversifiée de la terre qui remplit à la foisdes fonctions écologiques et économiques. La majorité de ces exploitations gèrent des forêts de succession, des bambous et des systèmes agroforestiers qui servent de stratégie d’adaptation aux risques liés au changement climatique. Grâce aux connaissances des familles d’agriculteurs, il a étéidentifié que les espèces d’arbres utilisées pour fournir des services de soutien, de régulation et d’approvisionnement de l’écosystème dans la culture du café sont principalement des légumineuses et des arbres fruitiers. D’autres espèces indigènes sont également utilisées pour l’ombrage et les haies vives. Ces résultats sont précieux pour la sélection des espèces d’arbres à propager dans les pépinières et à planter ultérieurement, et pour fournir de l’ombre à la culture du café. De même, ils renforcent les processusde transition agroécologique, soutiennent la certification des exploitations et contribuent à l’amélioration des revenus des familles et des organisations productrices de café.The Andes region of Colombia, known for its extensive coffee cultivation, also holds the country’s largest areas of successional forest. This analysis evaluated the use of forest, bamboo, and agroforestry systems in coffee farms as part of an agroecological transition strategy. The research was carried out in three municipalities on the Popayán plateau, located in the Department of Cauca in southwestern Colombia. Using a combination of qualitative and quantitative methods – including the Shade Tree Advice tool to assess ecosystem service provision – the study examined how these systems are integrated into the livelihoods of coffee-growing families. The results confirmed that these farms, managed by peasant families, use a diversified approach to land use that balances ecological sustainability with economic needs. Most farms incorporate successional forests, bamboo groves, and agroforestry systems as part of their adaptation strategies to the growing risks posed by climate change. Local knowledge played a key role in identifying the tree species that support ecosystem services essential to coffee farming. Leguminous and fruit trees are most commonly used to provide ecosystem support, including regulation and supply functions. Other native species are additionally used for shade and live fences. These results are valuable for selecting tree species for propagation in nurseries, planting on farms, and providing shade for coffee crops. Likewise, they strengthen the agroecological transition processes, support the certification of farms and contribute to improving the income of coffee-growing families and organisations.La mayor presencia de bosque sucesional en Colombia se encuentra en la región de los Andes, región en la que también existe un cultivo extensivo de café. Se realizó un análisis para evaluar el bosque, la guadua y la agroforestería en fincas de familias cafeteras como estrategia para la transición agroecológica. La investigación se llevó a cabo en tres municipios de la meseta de Popayán, en el departamento del Cauca, alsuroeste de Colombia. Se examinó la presencia de sistemas forestales, guaduales y agroforestales utilizando herramientas cualitativas y cuantitativas, y empleando la metodología Shade Tree Advice para determinar la oferta de servicios ecosistémicos. Los resultados confirmaron que las fincasevaluadas son lugares habitados por familias campesinas con un uso diversificado de la tierra que cumple funciones tanto ecológicas como económicas. La mayoría de estas fincas manejan bosques sucesionales,bambú y sistemas agroforestales que sirven como estrategia de adaptación a los riesgos derivados del cambio climático. A través del conocimiento de las familias campesinas, se identificó que las especies arbóreas utilizadas para brindar servicios de soporte, regulación y abastecimiento ecosistémico en elcultivo de café son principalmente leguminosas y frutales. Otras especies nativas son utilizadas adicionalmente para sombra y cercas vivas. Estos resultados son valiosos para la selección de especies arbóreas para su propagación en viveros y posterior plantación, y para proporcionar sombraal cultivo de café. Asimismo, fortalecen los procesos de transición agroecológica, apoyan la certificación de fincas y contribuyen a mejorar los ingresos de las familias y organizaciones cafetaleras