24 research outputs found

    A Privacy-Preserving Contactless Transport Service for NFC Smartphones

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    International audienceThe development of NFC-enabled smartphones has paved the way to new applications such as mobile payment (m-payment) and mobile ticketing (m-ticketing). However, often the privacy of users of such services is either not taken into account or based on simple pseudonyms, which does not offer strong privacy properties such as the unlinkability of transactions and minimal information leakage. In this paper, we introduce a lightweight privacy-preserving contactless transport service that uses the SIM card as a secure element. Our implementation of this service uses a group signature protocol in which costly cryptographic operations are delegated to the mobile phone

    Logging concessions and local livelihoods in Cameroon : From indifference to alliance?

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    Sustainable forest management gives the opportunity to better integrate the way local populations use their customary "village terroirs" in the logging activities. This requirement is explicitly stated in all forest laws of the Congo Basin countries but its implementation on the field remains under documented. In Cameroon, 30 forest management plans (FMP) for logging concessions have been reviewed to assess how they effectively include customary use rights. The integration of use rights into the FMPs is heterogeneous but always with very low enforcement. The weak influence of the FMP application on local practices is confirmed with an empirical survey that shows that natural, financial, and physical capitals in two villages of the eastern region of Cameroon have been little affected by the adjoining logging concession over the latest 13 years. Extrasector policies such as agriculture, road infrastructure, techniques, and land tenure are the real drivers of socioeconomic change at the local scale. Their impacts are facilitated by the presence of the logging concessions, which can contribute indirectly to improve local livelihoods. (Résumé d'auteur

    Cadmium but not lead exposure affects Xenopus laevis fertilization and embryo cleavage

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    International audienceAmong the toxicological and ecotoxicological studies, few have investigated the effects on germ cells, gametes or embryos, while an impact at these stages will result in serious damage at a population level. Thus, it appeared essential to characterize consequences of environmental contaminant exposures at these stages. Therefore, we proposed to assess the effects of exposure to cadmium and lead ions, alone or in a binary mixture, on early stages of Xenopus laevis life cycle. Fertilization and cell division during segmentation were the studied endpoints. Cadmium ion exposures decreased in the fertilization rates in a concentration-dependent manner, targeting mainly the oocytes. Exposure to this metal ions induced also delays or blockages in the embryonic development. For lead ion exposure, no such effect was observed. For the exposure to the mixture of the two metal ions, concerning the fertilization success, we observed results similar to those obtained with the highest cadmium ion concentration

    Repeatability and relative validity of a quantitative food-frequency questionnaire among French adults

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    International audienceBackground: A 50-item self-administered food frequency questionnaire (FFQ) was developed for French adults, to assess the intake of energy, 10 macronutrients, 11 vitamins, and 11 minerals, and to be used in the context of a medical consultation. Objective: To assess the repeatability and relative validity of this FFQ compared to a 7-day diet record (7-DR). Design: A total of 54 and 100 French adults were included in the repeatability and validation studies, respectively. Repeatability was assessed using two FFQs, the second carried out 3 weeks after the first. In the validation study, subjects first completed the FFQ, then the 7-DR the following week. Energy and nutrient intakes were compared using Pearson correlation. The degree of misclassification by the FFQ, compared to the 7-DR, was calculated by a contingency table of quintiles. Bland-Altman plots assessed the correlation between FFQ and 7-DR across the intake range. Results: Repeatability for intake, explored by Pearson correlation, was 0.62-0.90 (median: 0.81). Relative validity, as determined by Pearson correlation for the nutrient intake derived from the FFQ and 7-DR, was 0.36-0.80 (0.64). The FFQ tended to report higher fiber and micronutrient intake than 7-DR. Misclassification into opposite quintiles ranged 0-6% (1%), whereas classification into same or adjacent quintiles ranged 59-83% (74%). Bland-Altman plots showed good agreement for most nutrients across the range of intake. Conclusion: This new FFQ showed a high repeatability and good relative validity, and thanks to its short length, should be a useful tool for rapidly evaluating the nutrient intake of French adults

    A combined natural supplement lowers LDL cholesterol in subjects with moderate untreated hypercholesterolemia: A randomized placebo-controlled trial

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    Objective: To investigate the effect of a natural cholesterol-lowering supplement (NCLS) containing red yeast rice, policosanols and artichoke leaf extracts on blood lipid concentrations as well as on safety parameters when given over 16 weeks in 100 volunteers with untreated moderate hypercholesterolemia, in a randomized, double-blind, placebo-controlled trial. Results: Reduction of primary outcome low-density lipoprotein cholesterol [-0.22 g/L (95% confidence interval, CI:-0.31 to-0.12) corresponding to-14.3% from baseline (95% CI:-21.5 to-7.2) compared to placebo], as well as total cholesterol, apolipoprotein B100 and apolipoprotein B100/apolipoprotein A-I ratio, were observed after 16 weeks of supplementation with NCLS. These effects were already observed at Week 4 and 10 of supplementation. No significant changes were observed in high-density lipoprotein, triacylglycerol, creatine kinase, lactate dehydrogenase and coenzyme Q10 levels, as well as in markers of liver and renal function. Conclusions: The NCLS was effective in reducing low-density lipoprotein cholesterol and apolipoprotein B100 in subjects with moderate hypercholesterolemia, without modifying safety parameters. © 2013 Informa UK Ltd. All rights reserved.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

    LDL-cholesterol-lowering effect of a dietary supplement with plant extracts in subjects with moderate hypercholesterolemia

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    International audienceRed yeast rice (RYR), sugar cane-derived policosanols (SCdP) and artichoke leaf extracts (ALEs) are currently incorporated alone or in combination into dietary supplements for their potential low-density-lipoprotein cholesterol (LDL-cholesterol)-lowering effects. Yet, there is no information supporting the efficacy of this association on the reduction in LDL-cholesterol. The main objective of this study was to investigate the effects of a new dietary supplement (DS) with RYR, SCdP and ALEs on LDL-cholesterol. In a double-blind, randomized, parallel controlled study, 39 subjects from 21 to 55 years with moderate hypercholesterolemia without drug treatment were assigned to 2 groups and then consumed either a DS containing RYR, SCdP and ALEs or a placebo over a 16-week period. Plasma concentrations of lipids [LDL-cholesterol, total cholesterol (TC), high-density-lipoprotein cholesterol (HDL-cholesterol), triacylglycerols (TG)] and plasma levels of vitamins C and E, total polyphenols and malondialdehyde were determined at baseline and after 4, 8, 12 and 16 weeks. LDL-cholesterol and TC were reduced by, respectively, 21.4 % (95 % CI, -13.3 to -24.9 %, p < 0.001) and 14.1 % (95 % CI, -10.1 to -18.0 %, p < 0.001) at week 16 in the DS group compared with baseline. Similar results were obtained at weeks 4, 8 and 12. TG decreased by 12.2 % after 16 weeks in the DS group (95 % CI: -24.4 to -0.1 %, p < 0.05). For the vitamin E/TC ratio, a difference was observed between groups at week 16 (p < 0.05). Other parameters were not modified. Daily consumption of this new DS decreased LDL-cholesterol and TC and is therefore an interesting, convenient aid in managing mild to moderate hypercholesterolemia
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