Effect of early, short-term supplementation on weight and linear growth of 4-7-mo-old infants in developing countries : a four-country randomized trial

The effect of supplementation on growth was tested by means of four similar controlled randomized trials in the Congo (n = 120), Senegal (n = 110), Bolivie (n = 127), and New Caledonia (n = 90). Four month-old infants were randomly allocated to supplement or control groups. A cereal-based precooked porridge was offered twice daily for 3 mo and consumption was monitored. Both groups were free to eat local food. At 7 mo of age, all infants were still breast-fed in the Congo, Senegal, and Bolivia compared with 47% in the New Caledonia. Mean daily consumption of the supplement varied among countries (558-790 kJ/d). Mean length at 4 mo was lowest in Bolivia, higher in Senegal and the Congo, and near the National Center for Health Statistics reference in New Caledonia. The mean 4-7 mo length increment was 0,48 cm higher for supplemented than for control infants in Senegal (P < 0.05), whereas weight increments did not differ. No significant effect was found in the other countries. (Résumé d'auteur

Pluridisciplinarité et déconstruction du récit modernisateur. Le cas de l'Aubrac

International audienc

Pluridisciplinarité et déconstruction du récit modernisateur. Le cas de l'Aubrac

International audienc

Pluridisciplinarité et déconstruction du récit modernisateur. Le cas de l'Aubrac

International audienc

Association rule mining to help detect plant phenolic compounds putatively involved in decreased ruminal methane production in vitro: In the virgin forest of unknown bioactive plant phenolic compounds, association rules work like bushcutters clearing pathways to help discover active compounds

International audienceIntroduction In the search for natural alternatives to synthetic chemicals able to mitigate methane emission by ruminants, bioactive plant secondary metabolites are valuable candidates. However, these phytochemicals come in myriad chemical structures, and any one plant may contain hundreds of them. Even in plant extracts containing tannins, saponins or essential oils, it is difficult to link the presence of a compound or combination to the plant's activity. Here we focus on low-molecular-weight (0.5) were discarded before data mining to avoid false-positives. With the minimum thresholds of 5 for S and 0.5 for C, there were 205 candidate peaks. In a first strategy, results were filtered via the constraints of a) co-occurrence of the peak in the 280 and 320 nm matrices and b) C > 0.65, which narrowed the candidate peaks down to 28. In a second strategy, the constraints were that the peaks had to be major (i.e. more than 10 times the area of the median peak) and present in the plants that showed high antimethanogenic effect (outliers), which narrowed the candidate peaks down to 24. Combining the two strategies resulted in 7 candidate peaks. One peak was easily identified as gallic acid. Based on absorbance spectrum between 200 and 400 nm, three others were cinnamic acid derivatives and two were flavonols. Conclusion Association rules mining was able to select a compact number of peaks making identification feasible. The effect of these pure compounds now has to be verified for proof of the concept. While the algorithm works with qualitative data, using strategy which selects among the major peaks of the profiles serves to integrate the quantitative aspect. Acknowledgements We thank ethnobotanist G. Lalière and the Conservatoire Botanique National du Massif Central for plant collection

EFFETS PRÉCOCES D'UNE BRÈVE ÉLÉVATION DE LA TEMPÉRATURE TESTICULAIRE SUR LA SPERMATOGENÈSE DU BÉLIER

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Insights on the Electrocatalytic Seawater Splitting at Heterogeneous Nickel-Cobalt Based Electrocatalysts Engineered from Oxidative Aniline Polymerization and Calcination

International audienceGiven the limited access to freshwater compared to seawater, a growing interest surrounds the direct seawater electrolysis to produce hydrogen. However, we currently lack efficient electrocatalysts to selectively perform the oxygen evolution reaction (OER) over the oxidation of the chloride ions that are the main components of seawater. In this contribution, we report an engineering strategy to synthesize heterogeneous electrocatalysts by the simultaneous formation of separate chalcogenides of nickel (NiSx, x = 0, 2/3, 8/9, and 4/3) and cobalt (CoSx, x = 0 and 8/9) onto a carbon-nitrogen-sulfur nanostructured network. Specifically, the oxidative aniline polymerization in the presence of metallic cations was combined with the calcination to regulate the separate formation of various self-supported phases in order to target the multifunctional applicability as both hydrogen evolution reaction (HER) and OER in a simulated alkaline seawater. The OER’s metric current densities of 10 and 100 mA cm−2 were achieved at the bimetallic for only 1.60 and 1.63 VRHE, respectively. This high-performance was maintained in the electrolysis with a starting voltage of 1.6 V and satisfactory stability at 100 mA over 17 h. Our findings validate a high selectivity for OER of ~100%, which outperforms the previously reported data of 87–95%

Probing Oxygen-to-Hydrogen Peroxide Electro-Conversion at Electrocatalysts Derived from Polyaniline

International audienceHydrogen peroxide (H2O2) is a key chemical for many industrial applications, yet it is primarily produced by the energy-intensive anthraquinone process. As part of the Power-to-X scenario of electrosynthesis, the controlled oxygen reduction reaction (ORR) can enable the decentralized and renewable production of H2O2. We have previously demonstrated that self-supported electrocatalytic materials derived from polyaniline by chemical oxidative polymerization have shown promising activity for the reduction of H2O to H2 in alkaline media. Herein, we interrogate whether such materials could also catalyze the electro-conversion of O2-to-H2O2 in an alkaline medium by means of a selective two-electron pathway of ORR. To probe such a hypothesis, nine sets of polyaniline-based materials were synthesized by controlling the polymerization of aniline in the presence or not of nickel (+II) and cobalt (+II), which was followed by thermal treatment under air and inert gas. The selectivity and faradaic efficiency were evaluated by complementary electroanalytical methods of rotating ring-disk electrode (RRDE) and electrolysis combined with spectrophotometry. It was found that the presence of cobalt species inhibits the performance. The selectivity towards H2O2 was 65–80% for polyaniline and nickel-modified polyaniline. The production rate was 974 ± 83, 1057 ± 64 and 1042 ± 74 µmolH2O2 h−1 for calcined polyaniline, calcined nickel-modified polyaniline and Vulcan XC 72R (state-of-the-art electrocatalyst), respectively, which corresponds to 487 ± 42, 529 ± 32 and 521 ± 37 mol kg−1cat h−1 (122 ± 10, 132 ± 8 and 130 ± 9 mol kg−1cat cm−2) for faradaic efficiencies of 58–78%