Ceramic matrix composites for liner system of radioactive waste disposal cells

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Influence of fillers on mechanical properties of ATH filled EPDM during ageing by gamma irradiation

International audienceThe presence of a significant content of fillers accelerates the degradation of ATH filled EPDM subjected to gamma irradiation at room temperature. Above the melting temperature of the EPDM, this induces a decrease in the apparent mechanical reinforcement of the fillers. This also promotes de-cohesion mechanisms which leads to an increase in the strain at break with irradiation dose. It is not clear whether the use of a filler treatment attenuates this accelerating effect or not; however, part of this treatment remains efficient at a high dose and seems also to delay but not suppress the occurrence of de-cohesion mechanisms at large strain. Moreover, at room temperature, i.e. below the melting temperature, all the consequences of ageing by gamma irradiation are strongly attenuated by the presence of a semicrystalline microstructure, the morphology of which is not too strongly modified by irradiation. (C) 2010 Elsevier Ltd. All rights reserved

Evidence of trophic transfer of microcystins from the gastropod Lymnaea stagnalis to the fish Gasterosteus aculeatus.

International audienceAccording to our previous results the gastropod Lymnaea stagnalis exposed to MC-producing cyanobacteria accumulates microcystins (MCs) both as free and covalently bound forms in its tissues, therefore representing a potential risk of MC transfer through the food web. This study demonstrates in a laboratory experiment the transfer of free and bound MCs from L. stagnalis intoxicated by MC-producing Planktothrix agardhii ingestion to the fish Gasterosteus aculeatus. Fish were fed during five days with digestive glands of L. stagnalis containing various concentrations of free and bound MCs, then with toxin-free digestive glands during a 5-day depuration period. MC accumulation was measured in gastropod digestive gland and in various fish organs (liver, muscle, kidney, and gills). The impact on fish was evaluated through detoxification enzyme (glutathion-S-transferase, glutathion peroxydase and superoxyde dismutase) activities, hepatic histopathology, and modifications in gill ventilation, feeding and locomotion. G. aculeatus ingestion rate was similar with intoxicated and toxin-free diet. Fish accumulated MCs (up to 3.96 ± 0.14 μg g−1 DW) in all organs and in decreasing order in liver, muscle, kidney and gills. Hepatic histopathology was moderate. Glutathion peroxydase was activated in gills during intoxication suggesting a slight reactive oxygen species production, but without any impact on gill ventilation. Intoxication via ingestion of MC-intoxicated snails impacted fish locomotion. Intoxicated fish remained significantly less mobile than controls during the intoxication period possibly due to a lower health condition, whereas they showed a greater mobility during the depuration period that might be related to an acute foraging for food. During depuration, MC elimination was total in gills and kidney, but partial in liver and muscle. Our results assess the MC transfer from gastropods to fish and the potential risk induced by bound MCs in the food web

Why are there so many small woodlots in southwestern France landscapes?

Despite a trend during the last century towards a disconnection between agriculture and forestry, small woodlots strongly associated to farming activities are still very common in south western France. To explain the origin of this particularity and its consequences, we engaged ethnological, biotechnical and ecological studies. The ethnological study showed that the ‘house-centred’ social system - which is characteristic in this region - has shaped landscapes and reinforced the need for scattered small woodlots. Due to a principle of self-sufficiency, each farm had to have a direct access on its property or in its vicinity to all the resources needed. Woodlots had been maintained on lands that might have been cultivated and they contain a large diversity of woody species - even in the dominant tree layer - corresponding to the species needed for the family uses. Even if they are less able to apply all the usual practices, small woodlots are still seen by farmers as important components of their resources and landscapes. Their management lead to a particularly fine-grained mosaic of stands with different historical trajectories. Ecological studies revealed that these woodlots, and especially their edges, are key components of processes impacting agricultural activities, such as pest regulation. We argue that the small woodlots maintained in rural landscapes in south western France are beneficial for agriculture, forestry and rural activities, especially in a global change perspective. The question is how to keep their characteristics when their managers are leaving because of the lack of support from policy makers

A set of pedagogical recommendations for improving the integrated approach to childhood overweight and obesity: A Delphi study

Background: Tackling the increasing global problem of childhood overweight and obesity requires an integrated approach. Studies increasingly emphasize the importance of the parents' role in interventions designed to prevent overweight in children. The aim of this study was to develop a unified set of recommendations for healthy parenting practices that can be applied by all professionals who work with children age 4-13 years and can contribute to strengthening the integrated approach to childhood overweight. Methods: A modified Delphi procedure was used to reach consensus regarding what these pedagogical recommendations should encompass. The 30 panelists were professionals and researchers who work with children age 4-13 in the domains of health care, overweight, parenting, education, nutrition, and/or sports. The procedure consisted of: i) extracting existing pedagogical recommendations from national guidelines and professional protocols, ii) appraising and prioritizing these recommendations in terms of relevance through two rounds of questionnaires, and iii) meeting to discuss and approve the set of recommendations. Results: Consensus was reached for one set of eleven pedagogical theme-based recommendations designed to support and instruct parents how to stimulate healthy energy balance-related behaviors in their child. Each recommendation contained information regarding: i) which behaviors in the child and/or parent are important, ii) why this is important, and iii) how parents can stimulate this behavior by applying parenting skills in daily life. The eleven themes were: modeling, positive parenting, breakfast, varied diet, sugar-sweetened beverages, snacks, physical activity, playing sports, quantity of screen time, screen time during meals, and sleep. Conclusion We developed a set of recommendations for healthy parenting that can be used by various professionals working with children age 4-13 and can contribute to creating an integrated approach to childhood overweight. We also developed a web-based app called “Recommendations for Healthy Parenting” as a convenient tool for following these recommendations

Case report: Parsonage-turner syndrome in a melanoma patient treated by BRAF/MEK inhibitors after immune checkpoint inhibitors

IntroductionCombination molecular BRAF/MEK inhibitors targeted therapy has been shown to improve overall survival in patients with BRAF V600 mutated unresectable or metastatic melanoma. Most patients treated with BRAF/MEK inhibitors will experience adverse events but neurological adverse events (nAEs) remain rare.Case reportA 42-year-old woman diagnosed with metastatic melanoma presented with an intense pain in the left shoulder 7 days after the beginning of encorafenib/binimetinib after immune checkpoint inhibitors (ICI) combination. No other triggering factors were identified. Electromyogram performed one month after the pain onset revealed a left brachial plexopathy suggestive of a Parsonage-Turner syndrome. The weakness slowly improved with intensive rehabilitation and targeted therapies were continued.ConclusionWe report the first case of Parsonage-Turner syndrome in a melanoma patient treated with encorafenib/binimetinib following checkpoint inhibitors combination.We cannot rule out the implication of ICI in the development of this syndrome but the rapid onset of the symptoms after the beginning of targeted therapies makes their involvment more likely.Given the increased use of BRAF/MEK inhibitors in managing of stage III and IV melanoma, as well as the development in stage II, clinicians should be aware of this potential side effect

The effectiveness of a web-based Dutch parenting program to prevent overweight in children 9–13 years of age:Results of a two-armed cluster randomized controlled trial

INTRODUCTION: Although parental support is an important component in programs designed to prevent overweight in children, current programs pay remarkably little attention to the role of parenting. We therefore developed a web-based parenting program entitled “Making a healthy deal with your child”. This e-learning program can be incorporated into existing overweight prevention programs. The aim of this study was to determine the effectiveness of this e-learning program. MATERIALS AND METHODS: The effectiveness was examined in a two-armed cluster randomized controlled trial. The participants were 475 parent-child dyads of children 9–13 years of age in the Netherlands who participated in an existing schoolclass-based overweight prevention program. At the school grade level, parents were randomly assigned to either the intervention or the control condition. Measurements were taken from both parents and children at baseline, and 5 and 12 months after baseline. Primary outcomes included the child’s dietary and sedentary behavior, and level of physical activity. Secondary outcomes included general parenting style, specific parenting practices, and parental self-efficacy. Linear mixed effects models and generalized linear mixed effects models were conducted in R. RESULTS: Intention-to-treat analyses and completers only revealed no significant effects between the intervention and control condition on energy balance-related behaviors of the child and parenting skills after correction for multiple testing. The parents’ mean satisfaction with the e-learning program (on a 10-point scale) was 7.0±1.1. CONCLUSIONS: Although parents were generally satisfied with the parenting program, following this program had no significant beneficial effects regarding the children’s energy balance-related behaviors or the parenting skills compared to the control condition. This program may be more beneficial if used by high-risk groups (e.g. parents of children with unhealthy energy balance-related behaviors and/or with overweight) compared to the general population, warranting further study

Specific Silencing of the REST Target Genes in Insulin-Secreting Cells Uncovers Their Participation in Beta Cell Survival

The absence of the transcriptional repressor RE-1 Silencing Transcription Factor (REST) in insulin-secreting beta cells is a major cue for the specific expression of a large number of genes. These REST target genes were largely ascribed to a function of neurotransmission in a neuronal context, whereas their role in pancreatic beta cells has been poorly explored. To identify their functional significance, we have generated transgenic mice expressing REST in beta cells (RIP-REST mice), and previously discovered that REST target genes are essential to insulin exocytosis. Herein we characterized a novel line of RIP-REST mice featuring diabetes. In diabetic RIP-REST mice, high levels of REST were associated with postnatal beta cell apoptosis, which resulted in gradual beta cell loss and sustained hyperglycemia in adults. Moreover, adenoviral REST transduction in INS-1E cells led to increased cell death under control conditions, and sensitized cells to death induced by cytokines. Screening for REST target genes identified several anti-apoptotic genes bearing the binding motif RE-1 that were downregulated upon REST expression in INS-1E cells, including Gjd2, Mapk8ip1, Irs2, Ptprn, and Cdk5r2. Decreased levels of Cdk5r2 in beta cells of RIP-REST mice further confirmed that it is controlled by REST, in vivo. Using siRNA-mediated knockdown in INS-1E cells, we showed that Cdk5r2 protects beta cells against cytokines and palmitate-induced apoptosis. Together, these data document that a set of REST target genes, including Cdk5r2, is important for beta cell survival

Parents' underestimation of their child's weight status. Moderating factors and change over time: A cross-sectional study

BACKGROUND: Parents' underestimation of their child's weight status can hinder active participation in overweight prevention programs. We examined the level of agreement between the parents' perception of their child's weight status and the child's actual weight status, moderating factors, and change over time. METHODS: This cross-sectional study used data collected in 2009 (n = 8105), 2013 (n = 8844) and 2017 (n = 11,022) from a community-based survey conducted among parents of children age 2-12 years in the Netherlands. Parents classified their perception of their child's weight status on a 5-point Likert scale. In 2009 and 2013, the child's BMI was calculated from self-reported data by parents. The level of agreement between the parent's perception of the weight status and the actual weight status was examined using Cohen's kappa. The role of demographic factors on parents' perception were examined using logistic regression. RESULTS: In 2009, 2013 and 2017, 6%, 6% and 5% of the parents, respectively, classified their child as heavy/extremely heavy. In 2009 and 2013, 64.7% and 61.0% of parents, respectively, underestimated the weight status of their overweight child. This was even higher among parents of obese children. Overall, the agreement between the parents' perception and the actual weight status improved from 2009 (kappa = 0.38) to 2013 (kappa = 0.43) (p<0.05), but remained unsatisfactory. The parents' underestimation of their child's overweight/obesity status was associated with the child's age in 2009 and 2013 (2-7 years; OR: 0.18), the child's gender in 2009 (male; OR: 0.55), and the parents' education level in 2009 (middle and high education; OR: 0.56 and 0.44 respectively). CONCLUSIONS: Parents' underestimation of their child's weight status remains alarmingly high, particularly among parents of young, obese children. This underestimation is a barrier to preventing childhood overweight/obesity. Healthcare professionals should take this underestimation into consideration and should actively encourage parents to take steps to prevent overweight/obesity in their children