59 research outputs found
Dynamic sizing of required balancing capacities: the operational approach in France
System operators employ operating reserves to deal with unexpected variations
of demand and generation and guarantee the security of supply. However, they
face new challenges to ensure this mission with the increasing share of
renewable generation. This article focuses on the operational approach adopted
by the French transmission system operator RTE for dynamically sizing the
required margins in the dynamic margin monitoring strategy context. It relies
on continuous forecasts of the main drivers of the uncertainties of the system
imbalance. Four types of forecast errors, assumed to be independent, are
considered in this approach: the errors in the wind and photovoltaic power
generation, production of conventional power units, and electricity
consumption. Then, the required margin is the result of comparing the global
forecast error, computed as the convolution of these independent errors, with a
security of supply criterion. This study presents the results of this method
implemented at RTE and used in real-time operation.Comment: Preprint version of the paper accepted for EEM 23 conferenc
Even a Previous Light-Active Physical Activity at Work Still Reduces Late Myocardial Infarction and Stroke in Retired Adults Aged>65 Years by 32%: The PROOF Cohort Study
Background: Work may contribute significantly to daily physical activity (PA) and sedentary behavior (SB). Physical inactivity and SB at work might be two major risk factors for premature morbidity. Therefore, the aim of this research was to describe self-reported past PA and SB at work and during leisure time within the PROOF cohort subjects, and to determine consequences of PA and SB on late health of these now retired workers.Material and Methods: The PROOF cohort study was used to prospectively allow assessment of the predictive value of PA and SB at work and during leisure time among a healthy retired French population, with regard to cardiovascular and cerebrovascular events. PA (MET-h/week) and SB (h/d) were assessed using the Population Physical Activity Questionnaire (POPAQ) and the modified Global Physical Activity Questionnaire (GPAQ). Odds ratios (ORs with 95% CIs) for cardiovascular and cerebrovascular events were associated with each level of PA at work: light (<3 METs), moderate (3â5.9 METs), vigorous (â„6 METs) and were compared to SB at work.Results: Out of the 1011 65-year-old subjects initially included, the 15-year follow-up has been currently completed for 688 (68%) subjects; 89 deaths (all-cause mortality, 9%) and 91 fatal and non-fatal cardiovascular and cerebrovascular events (9%), were reported. An active work (light, moderate, or vigorous intensity) was associated with a 21% reduced risk of cardiovascular (myocardial infarction) and cerebrovascular events (stroke) (OR = 0.79, 95% CI: 0.32â0.91, p < 0.02) compared to sedentary work. This relationship was already significant for light intensity work (32%; i.e., OR = 0.68, 95% CI: 0.31â0.87, p < 0.02).Conclusion: There is strong causal evidence linking PA and SB at work with late cardiovascular and cerebrovascular disease. All in all, the risk for onset of myocardial infarction and stroke was lower among those who had a previous active work compared to those with previous sedentary work. Even previous light active work produced substantial health benefits.Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT00759304
Relationship between moderate-to-vigorous, light intensity physical activity and sedentary behavior in a prospective cohort of older French adults: a 18-year follow-up of mortality and cardiovascular events â the PROOF cohort study
BackgroundIt is well documented that moderate-to-vigorous intensity physical activity (MVPA) is effective in the prevention of major chronic diseases. Even though the current international physical activity (PA) guidelines still mainly focus on MVPA, the topic of the most recent epidemiological studies has shifted from MVPA to light intensity physical activity (LPA), owing to the necessity of promoting all activities vs. sedentary behavior (SB). However, the evidence remains currently limited. Thus, the clarification of the effects of LPA and the close relationship with SB is crucial to promote public health.MethodPA and SB were assessed by a validated self-administered questionnaire (POPAQ) investigating 5 different types of PA during the 7 previous days. PA was measured in metabolic equivalent of task (MET)-h, which refers to the amount of energy (calories) expended per hour of PA. SB was measured in hour/day. Medical histories and examinations were taken during each clinical visit to determine clinical events. All-cause mortality was established using the same procedure and by checking local death registries. The relationships between the intensity of PA (light, moderate to vigorous) and mortality and between the periods of SB and mortality or CV events were analyzed by splines and COX models, adjusted for sex and year of birth.ResultsFrom the 1011 65-year-old subjects initially included in 2001 (60% women), the last 18-year follow-up has been currently completed since 2019. A total of 197 deaths (19.2%, including 77 CV deaths) and 195 CV events (19.3%) were reported. Averages (standard deviation) of MVPA, LPA and SB were, respectively, 1.2âh/d (0.3), 5.8âh/d (1.1), and 6.6âh/d (2.3). For all-cause deaths, as well as CV deaths, the splines were significant for LPA (pâ=â0.04 and pâ=â0.01), and MVPA (pâ<â0.001 and pâ<â0.001), but not for SB (pâ=â0.24 and pâ=â0.90). There was a significant reduction in CV events when SB was decreasing from 10.9 to 3.3âh/d.ConclusionThe PROOF cohort study shows a clear doseâresponse between the dose of LPA, MVPA, SB and risk of mortality. These findings provide additional evidence to support the inclusion of LPA in future PA guidelines
Synaptic Maturation at Cortical Projections to the Lateral Amygdala in a Mouse Model of Rett Syndrome
Rett syndrome (RTT) is a neuro-developmental disorder caused by loss of function of Mecp2 - methyl-CpG-binding protein 2 - an epigenetic factor controlling DNA transcription. In mice, removal of Mecp2 in the forebrain recapitulates most of behavioral deficits found in global Mecp2 deficient mice, including amygdala-related hyper-anxiety and lack of social interaction, pointing a role of Mecp2 in emotional learning. Yet very little is known about the establishment and maintenance of synaptic function in the adult amygdala and the role of Mecp2 in these processes. Here, we performed a longitudinal examination of synaptic properties at excitatory projections to principal cells of the lateral nucleus of the amygdala (LA) in Mecp2 mutant mice and their wild-type littermates. We first show that during animal life, Cortico-LA projections switch from a tonic to a phasic mode, whereas Thalamo-LA synapses are phasic at all ages. In parallel, we observed a specific elimination of Cortico-LA synapses and a decrease in their ability of generating presynaptic long term potentiation. In absence of Mecp2, both synaptic maturation and synaptic elimination were exaggerated albeit still specific to cortical projections. Surprisingly, associative LTP was unaffected at Mecp2 deficient synapses suggesting that synaptic maintenance rather than activity-dependent synaptic learning may be causal in RTT physiopathology. Finally, because the timing of synaptic evolution was preserved, we propose that some of the developmental effects of Mecp2 may be exerted within an endogenous program and restricted to synapses which maturate during animal life
Transcriptional role of cyclin D1 in development revealed by a âgenetic-proteomicâ screen
Author manuscript: 2010 September 22.Cyclin D1 belongs to the core cell cycle machinery, and it is frequently overexpressed in human cancers[superscript 1, 2]. The full repertoire of cyclinâD1 functions in normal development and oncogenesis is unclear at present. Here we developed Flag- and haemagglutinin-tagged cyclinâD1 knock-in mouse strains that allowed a high-throughput mass spectrometry approach to search for cyclinâD1-binding proteins in different mouse organs. In addition to cell cycle partners, we observed several proteins involved in transcription. Genome-wide location analyses (chromatin immunoprecipitation coupled to DNA microarray; ChIP-chip) showed that during mouse development cyclinâD1 occupies promoters of abundantly expressed genes. In particular, we found that in developing mouse retinasâan organ that critically requires cyclinâD1 function[superscript 3, 4]âcyclinâD1 binds the upstream regulatory region of the Notch1 gene, where it serves to recruit CREB binding protein (CBP) histone acetyltransferase. Genetic ablation of cyclinâD1 resulted in decreased CBP recruitment, decreased histone acetylation of the Notch1 promoter region, and led to decreased levels of the Notch1 transcript and protein in cyclinâD1-null (Ccnd1-/-) retinas. Transduction of an activated allele of Notch1 into Ccnd1-/- retinas increased proliferation of retinal progenitor cells, indicating that upregulation of Notch1 signalling alleviates the phenotype of cyclinâD1-deficiency. These studies show that in addition to its well-established cell cycle roles, cyclinâD1 has an in vivo transcriptional function in mouse development. Our approach, which we term âgeneticâproteomicâ, can be used to study the in vivo function of essentially any protein
De novo TBR1 variants cause a neurocognitive phenotype with ID and autistic traits:report of 25 new individuals and review of the literature
TBR1, a T-box transcription factor expressed in the cerebral cortex, regulates the expression of several candidate genes for autism spectrum disorders (ASD). Although TBR1 has been reported as a high-confidence risk gene for ASD and intellectual disability (ID) in functional and clinical reports since 2011, TBR1 has only recently been recorded as a human disease gene in the OMIM database. Currently, the neurodevelopmental disorders and structural brain anomalies associated with TBR1 variants are not well characterized. Through international data sharing, we collected data from 25 unreported individuals and compared them with data from the literature. We evaluated structural brain anomalies in seven individuals by analysis of MRI images, and compared these with anomalies observed in TBR1 mutant mice. The phenotype included ID in all individuals, associated to autistic traits in 76% of them. No recognizable facial phenotype could be identified. MRI analysis revealed a reduction of the anterior commissure and suggested new features including dysplastic hippocampus and subtle neocortical dysgenesis. This report supports the role of TBR1 in ID associated with autistic traits and suggests new structural brain malformations in humans. We hope this work will help geneticists to interpret TBR1 variants and diagnose ASD probands
LâarrĂȘt Dell et le contrĂŽle de la compĂ©tence arbitrale au stade du renvoi Ă lâarbitrage
Transcriptional Regulation by a DNA-associated Form of Cyclin D1
International audienceBesides its function as a cell cycle regulator, cyclin D1 interacts with transcription factors to regulate gene activation. In this study, we show that cyclin D1 is recruited to the p21waf1 promoter by a STAT3-NcoA complex. The association of cyclin D1 with DNA prevented the recruitment of the CBP histone acetylase and RNA polymerase II, leading to an inhibition of the p21waf1 gene. Confirming the transcriptional function of the protein, the expression of the p21waf1 gene was enhanced in cyclin D1Ű/Ű fibroblasts or upon siRNA-mediated down-regulation of the cyclin. Moreover, the STAT3-mediated activation of p21waf1 was also inhibited in breast cancer cells containing elevated levels of cyclin D1. Altogether, these results suggest that the transcriptional activities of cyclin D1 might play an important role in the regulation of cell-cycle regulatory genes and that these functions are probably involved in cell transformation
Dynamic vapour sorption isotherms and isosteric heats of sorption of two edible insects (Cirina forda and Rhyncophorus ferrugineus)
info:eu-repo/semantics/publishe
Dynamic vapour sorption isotherms and isosteric heats of sorption of two edible insects (Cirina forda and Rhyncophorus ferrugineus)
Cirina forda (Cf) and Rhyncophorus ferrugineus (Rf) are widely consumed insects in tropical Africa. Drying is one of the main conservation techniques to improve their availability for distant markets and outside their harvest seasons. The main goal of this study was to investigate thee sorption isotherms of these insects and estimate their shelf-life. Sorption isotherms of these two insects were determined at 25, 30, 40 and 50°C using a Dynamic Vapor Sorption (DVS) device. Five isothermal sorption models were fitted to the experimental data, and Peleg equation was found to give the best fit for both insects. Both insects exhibited sorption isotherm of type III indicating monolayer-multilayer behavior with limited hysteresis. Amplitude of hysteresis was higher for Rf than for Cf. According to the sorption isotherms to ensure a safe storage at 25 and 30°C the Rf larvae must be dried at 8.8 % and 8 % respectively. Cf caterpillars must be dried to 9.5 and 9.4 % for respective storage at 25 and 30°C. Based on Kinshasa climate data when these two insects are left in contact with ambient air, their equilibrium moisture content can evolve to values higher than values guaranteeing a safe storage. This suggests that for better preservation the dried insects should be packed in airtight packages. Using Heiss-Eichner model, dry base moisture contents of 6.9 % and 8.5 % respectively for Rf and Cf were predicted to ensure the expected shelf-life of 12 months at 30°C when insects are packaged in polyethylene films.info:eu-repo/semantics/nonPublishe
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