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Maternal anthropometric measurements in pregnancy and child neurocognitive and behavioral development at 1 and 6 years of age – a cohort study in Benin, Sub-Saharan Africa
No full textInternational audienceBackgroundMaternal malnutrition, especially obesity, is hypothesized to impact offspring neurodevelopment, but less is known in sub-Saharan Africa where undernutrition is highly prevalent.ObjectiveThis study aimed to investigate the association between maternal nutritional status during pregnancy and neurocognitive and behavioral development in children at age one and six years, in a mother-child cohort from Benin.MethodsThis prospective cohort study included surviving singletons born to pregnant women in Allada, Benin. Cognitive and motor functions of 747 and 574 children were assessed at one and six years of age, respectively, in addition to behavioral difficulties and attention deficit and hyperactivity disorders. Statistical analysis using multiple linear regression models tested main associations, potential mediating factors were additionally adjusted for.Results17%, 72.5%, 7.7% and 2.5% of women were estimated to be underweight, normal weight, overweight and obese before pregnancy, respectively. Women who were underweight had a higher median weight gain [240 (170 – 300)] over the course of pregnancy, compared to normal BMI women [210 (160 – 260)], and overweight/obese women [150 (110 – 240)]. After exclusion of obese women, pre-pregnancy BMI was significantly associated with a higher motor scores (0.26, 95%CI 0.002-0.53) and cognitive scores (0.37, 95%CI 0.02-0.72) after adjustment for confounding factors. There was no association between gestational weight gain and offspring neurodevelopment at one and six years of age. There was no association between maternal BMI and gestational weight gain and behavior and attention deficit and hyperactivity disorders at six years of age.ConclusionsOur study suggests that poor maternal nutritional status before pregnancy may impair short- and long-term neurocognition in children in the Beninese context. Undernutrition in childhood has great impact and efforts to adequate prevention for both child and maternal undernutrition should be enforced in low- and middle-income countries
Un partage d’expérience autour de la pratique de l’interdisciplinarité sur les feux : le projet EcoSoFI (2022-2024)
No full textInternational audienceLes collaborations inter/transdisciplinaires autour de la compréhension des feux et de leur gestion sont plébiscitées, mais leur mise en œuvre ne va pas pour autant de soi. A partir du partage d’expériences de plusieurs scientifiques et gestionnaires, le présent article restitue la démarche que nous avons adoptée pour comprendre ces difficultés ; et tire quelques constats et propositions. Onconstate notamment la dominance des sciences biophysiques et le poids de la modélisation dans les interfaces entre recherche et gestion. Au sein des SHS, on observe également des partitions entre disciplines et sous-disciplines, ainsi qu’une « interdisciplinarité inachevée » dans l’analyse des changements de régimes de feux. La spécialisation disciplinaire a conduit à une autonomisation du questionnement et des méthodes, qui ne sont plus explicitées ni interrogées au regard des autres approches et du terrain. Nos propositions consistent à remettre en question les catégories implicites concernant les pratiques et les savoirs liés aux feux et à définir des protocoles de recherche permettant des problématisations communes à partir d’études de cas localisées et « concrètes »
Territoria Naturalia. Aménager sans altérer, entre partage et réserve
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Bioelectricity Harvesting via a Microbial Fuel Cell with Sulfonated Hypercrosslinked Polyphenols and Polyethersulfone Composite Proton-Conducting Membrane
No full textInternational audienceIn this research, a novel polyelectrolyte composite membrane was developed by combining sulfonated polyethersulfone (sPES) and sulfonated hypercrosslinked polymers (sHCP) to enhance microbial fuel cell (MFC) performances. Various characterization strategies confirmed that the incorporation of sulfonic groups boosted proton conductivity and hydrophilicity, with sHCP further enhancing these properties. The sulfonation degrees were measured at 51.80 % for sPES, 48.54 % for sHCP, and 66.05 % for the sPES/sHCP0.8 composite. Key physical properties included a water uptake (WU) of 54.30 %, surface roughness (SR) values of 21.53 % and 33.25 %, and ion-exchange capacity (IEC) measurements of 1.97 and 2.38 meq/g for sPES and sPES/sHCP0.8, respectively. Proton conductivity (PC) reached 4.03 mS/cm for sPES and 5.53 mS/cm for sPES/sHCP0.8. In contrast, Nafion-117 exhibited a high O 2 diffusion coefficient of 1.44 cm 2 /s and a transport rate coefficient of 0.123 cm/s, while sPES/sHCP0.8 demonstrated minimal O 2 migration, with diffusion coefficients of 1.73 × 10 -2 cm 2 /s and a transport rate of 2.45 × 10 -3 cm/s. The sPES/sHCP0.8 membrane displayed superior tensile stress, elastic modulus, and strain at break compared to PES, sPES, and Nafion-117, measuring 73.48 MPa, 7.49 %, and 15.80 MPa, respectively. Findings indicated that membrane selection is crucial for COD removal efficiency and energy generation. The MFC with the sPES/sHCP0.8 polyelectrolyte achieved a coulombic efficiency of 0.8 %, a COD reduction of 84.37 %, and an energy density of 80.96 mW/m 2 , outperforming Nafion-117 (28.56 mW/m 2 ) and sPES20 (28.56 mW/m 2 ) in batch mode over five days. Additionally, bioelectricity was harvested at 32.38 Wh/m 3 (NERv) and 10.9 kW/kg COD (NERs). However, the highest COD removal of 96.54 % was attained with MFCs using sPES20/sHCP160-0.8 and sPES20/sHCP180-0.4. The maximum I max was 690 mA/m 2 (1150 mA/ m 3 ) with sPES20/sHCP180-0.6, which also achieved the highest CE of 0.88 %. This study demonstrates that integrating sHCP enhances membrane properties while maintaining thermal and mechanical stability, significantly improving MFC performance
Orientation of nitration in bay-region of benzothioxanthene imide: A streamlined pathway to N- and S-annulated derivatives
No full textInternational audienceN-annulation has recently emerged as a powerful approach for modulating the optoelectronic properties of benzothioxanthene imide (BTI) derivatives, enabling their application in areas ranging from light-emitting devices to photodynamic therapy. In this study, we report an optimized synthetic strategy that reduces the original seven-step process for N-annulated BTIs to just four steps, achieving a similar to 40 % improvement in efficiency. Additionally, we introduce a novel S-annulated BTI derivative, extending the scope of heteroatom-involving ring fusion. Comparative analysis between N- and S-annulated compounds reveals the pronounced influence of a single-atom modification on the pi-conjugated system. These findings demonstrate the utility of annulation as a chemically accessible and versatile tool for fine-tuning molecular architectures with tailored photophysical properties
Projets alimentaires territoriaux et stratégies alimentaires locales : une comparaison France -Brésil
No full textInternational audienceThis text compares civil society and national and local policy actions targeting the food system in Brazil and France. It shows how the two countries have adopted mirror strategies, with France relying on a multitude of local initiatives led by local authorities and civil society, with little national support, while Brazil first developed a powerful national policy influenced by organised citizen networks to disseminate it at regional and local levels.Ce texte, en version longue par rapport à l'ouvrage à paraître, compare les actions de la société civile et politiques nationales et locales visant le système alimentaire, entre le Brésil et la France. Il montre comment les deux pays ont adopté des stratégies en miroir, la France se basant sur une multitude d'initiatives locales portées par les collectivités et la société civile, avec un faible portage national, pendant que le Brésil a d'abord développé une puissante politique nationale influencée par les réseaux citoyens organisés pour la diffuser aux échelles régionale et locale
Timed initial-state detectability of discrete-event systems by algebraic method
No full textInternational audienceIn this paper, we address the problem of initial-state detectability (I-detectability) for timed discrete-event systems modeled by time-interval automata (TIAs). An I-observer, defined over a timed event set, is developed to check both strong and weak I-detectability. Additionally, an I-detector structure is designed as an alternative method for verifying strong I-detectability, which is more efficient than the I-observer in certain cases. In addition, we are the first to formally define the concepts of strong and weak timed initial-state detectability (-I-detectability) within the framework of timed discrete-event systems. Specifically, I-detectability necessitates that the initial state of a system can be detected after a finite number of observations. From another perspective, -I-detectability entails that the initial state can be ascertained after a delay of time units. Under the assumption that every cycle in the TIA has strictly positive weight, we establish that a TIA is -I-detectable if and only if it satisfies the condition of being I-detectable. Finally, we introduce an algebraic method to compute the upper bound of time that needs to elapse before the initial state can be determined in an I-detectable TIA
Tuberculosis detection on chest X-rays using two-dimensional multiscale symbolic dynamic entropy
No full textAvailable online 14 July 2025International audienceSeveral radiological patterns associated with pulmonary tuberculosis (TB) have been identified on chest X-rays (CXR) used for screening purposes. As a result, several automatic computational tools have emerged for this purpose. We propose a new algorithm, two-dimensional multiscale symbolic dynamic entropy (MSDE), to develop a computational tool sensitive to these subtle patterns variations and noise robustness for evaluating CXR images from healthy and TB-diagnosed individuals. The one-dimensional SDE algorithm was previously shown to be more efficient in detecting amplitude variations and in computational calculations (compared to other entropy algorithms). Additionally, we also extracted first-order statistical parameters like standard deviation (SD), and mean of positive pixels (MPP), among others. These MSDE and first-order texture features were used to detect TB in each lung individually. The MSDE was validated using a synthetic dataset and optimized for the best set of parameters. We verified that, for both lungs, the MSDE values were significantly different between healthy and TB CXR images (), and the effect size was d 0.23. From the first-order parameters, only the mean, SD, entropy, and MPP were statistically different between both groups for the left lung (; d 0.22). For the right lung, all first-order features significantly differentiated TB patients (; d 0.28). Finally, we show that a multi-layer perceptron obtained 86.4 and 85.2% accuracy in detecting TB in the left and right lungs, respectively. The highest sensitivity values achieved in this study were 71.4% and 81.8% for the left and right lungs, respectively
Discrete numerical analysis of cohesive granular flow in a thin rotating drum: Flow regimes and cohesion estimation
No full textInternational audienceIn this study, we investigate the rheological behavior of cohesive granular flows within a rotating drum geometry using discrete element method (DEM) simulations. By systematically varying particle size, cohesion, and stiffness, we identify the emergence of distinct flow regimes-consistent with prior experimental observations. While the transitions between these regimes are primarily governed by cohesion, particle stiffness is also shown to significantly influence flow dynamics.To interpret the numerical results, we employ a dimensional analysis rooted in the physics of adhesive particle collisions. This analysis provides a conceptual framework for the remainder of the paper, which explores how "upscaled" discrete simulations can replicate experimental findings and help infer interparticle contact properties such as the adhesive surface energy. Notably, we use it to examine rotating drum experiments involving a unique class of granular materials, ice powders, which holds particular relevance in planetary science applications, and which flowability was shown to be strongly temperature-dependent.</div