13 research outputs found

    From SIR to SEAIRD: a novel data-driven modeling approach based on the Grey-box System Theory to predict the dynamics of COVID-19

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    Common compartmental modeling for COVID-19 is based on a priori knowledge and numerous assumptions. Additionally, they do not systematically incorporate asymptomatic cases. Our study aimed at providing a framework for data-driven approaches, by leveraging the strengths of the grey-box system theory or grey-box identification, known for its robustness in problem solving under partial, incomplete, or uncertain data. Empirical data on confirmed cases and deaths, extracted from an open source repository were used to develop the SEAIRD compartment model. Adjustments were made to fit current knowledge on the COVID-19 behavior. The model was implemented and solved using an Ordinary Differential Equation solver and an optimization tool. A cross-validation technique was applied, and the coefficient of determination R2R^2 was computed in order to evaluate the goodness-of-fit of the model. %to the data. Key epidemiological parameters were finally estimated and we provided the rationale for the construction of SEAIRD model. When applied to Brazil's cases, SEAIRD produced an excellent agreement to the data, with an %coefficient of determination R2R^2 ≄90%\geq 90\%. The probability of COVID-19 transmission was generally high (≄95%\geq 95\%). On the basis of a 20-day modeling data, the incidence rate of COVID-19 was as low as 3 infected cases per 100,000 exposed persons in Brazil and France. Within the same time frame, the fatality rate of COVID-19 was the highest in France (16.4\%) followed by Brazil (6.9\%), and the lowest in Russia (≀1%\leq 1\%). SEAIRD represents an asset for modeling infectious diseases in their dynamical stable phase, especially for new viruses when pathophysiology knowledge is very limited

    Sixteen-Year Monitoring of Particulate Matter Exposure in the Parisian Subway: Data Inventory and Compilation in a Database

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    The regularly reported associations between particulate matter (PM) exposure, and morbidity and mortality due to respiratory, cardiovascular, cancer, and metabolic diseases have led to the reduction in recommended outdoor PM10 and PM2.5 exposure limits. However, indoor PM10 and PM2.5 concentrations in subway systems in many cities are often higher than outdoor concentrations. The effects of these exposures on subway workers and passengers are not well known, mainly because of the challenges in exposure assessment and the lack of longitudinal studies combining comprehensive exposure and health surveillance. To fulfill this gap, we made an inventory of the PM measurement campaigns conducted in the Parisian subway since 2004. We identified 5856 PM2.5 and 18,148 PM10 results from both personal and stationary air sample measurements that we centralized in a database along with contextual information of each measurement. This database has extensive coverage of the subway network and will enable descriptive and analytical studies of indoor PM exposure in the Parisian subway and its potential effects on human health

    Physical activity, screen time and the COVID-19 school closures in Europe – an observational study in 10 countries

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    To date, few data on how the COVID-19 pandemic and restrictions affected children’s physical activity in Europe have been published. This study examined the prevalence and correlates of physical activity and screen time from a large sample of European children during the COVID-19 pandemic to inform strategies and provide adequate mitigation measures. An online survey was conducted using convenience sampling from 15 May to 22 June, 2020. Parents were eligible if they resided in one of the survey countries and their children aged 6–18 years. 8395 children were included (median age [IQR], 13 [10–15] years; 47% boys; 57.6% urban residents; 15.5% in self-isolation). Approximately two-thirds followed structured routines (66.4% [95%CI, 65.4–67.4]), and more than half were active during online P.E. (56.6% [95%CI, 55.5–57.6]). 19.0% (95%CI, 18.2–19.9) met the WHO Global physical activity recommendation. Total screen time in excess of 2 h/day was highly prevalent (weekdays: 69.5% [95%CI, 68.5–70.5]; weekend: 63.8% [95%CI, 62.7–64.8]). Playing outdoors more than 2 h/day, following a daily routine and being active in online P.E. increased the odds of healthy levels of physical activity and screen time, particularly in mildly affected countries. In severely affected countries, online P.E. contributed most to meet screen time recommendation, whereas outdoor play was most important for adequate physical activity. Promoting safe and responsible outdoor activities, safeguarding P.E. lessons during distance learning and setting pre-planned, consistent daily routines are important in helping children maintain healthy active lifestyle in pandemic situation. These factors should be prioritised by policymakers, schools and parents. Highlights ‱ To our knowledge, our data provide the first multi-national estimates on physical activity and total screen time in European children roughly two months after COVID-19 was declared a global pandemic. ‱ Only 1 in 5 children met the WHO Global physical activity recommendations. ‱ Under pandemic conditions, parents should set pre-planned, consistent daily routines and integrate at least 2-hours outdoor activities into the daily schedule, preferable on each day. Schools should make P.E. lessons a priority. Decision makers should mandate online P.E. be delivered by schools during distance learning. Closing outdoor facilities for PA should be considered only as the last resort during lockdowns

    RĂŽle de l’activitĂ© physique dans la lutte contre le syndrome mĂ©tabolique infantile

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    Le syndrome mĂ©tabolique est dĂ©fini comme la prĂ©sence conjointe, chez un mĂȘme individu, de plusieurs facteurs de risque (au moins 3 dans la majoritĂ© des dĂ©finitions) parmi les facteurs suivants : hypertriglycĂ©ridĂ©mie, hypertension artĂ©rielle, obĂ©sitĂ© abdominale, faible concentration de HDL-cholestĂ©rol (HDL-C), glycĂ©mie Ă  jeun Ă©levĂ©e. Il est dĂ©crit avec une frĂ©quence accrue chez l’enfant, essentiellement en prĂ©sence d’un surpoids/obĂ©sitĂ©. Parmi les mesures de prĂ©vention et de traitement utilisables chez l’enfant, l’activitĂ© physique apparaĂźt comme une option de choix. Cette synthĂšse discute l’intĂ©rĂȘt des programmes d’exercices aĂ©robies, de rĂ©sistance ou une combinaison des deux formes d’activitĂ© structurĂ©e, de mĂȘme que les activitĂ©s de la vie courante effectuĂ©es avec une intensitĂ© au moins Ă©quivalente Ă  celle d’une marche rapide

    Le conseil en activité physique dans le cadre des soins primaires

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    Les bienfaits d’une activitĂ© physique rĂ©guliĂšre sont dĂ©sormais unanimement reconnus par les communautĂ©s mĂ©dicale et scientifique. Paradoxalement, les donnĂ©es Ă©pidĂ©miologiques suggĂšrent qu’une proportion importante (> 60 %) de la population mondiale ne rĂ©alise pas suffisamment d’activitĂ© physique pour sa santĂ©. En Europe par exemple, la prĂ©valence de l’activitĂ© physique est seulement de 29 %. La France apparaĂźt dans ce contexte comme le pays le plus sĂ©dentarisĂ©. La participation des mĂ©decins et surtout du mĂ©decin traitant Ă  l’effort de santĂ© publique visant Ă  gĂ©nĂ©raliser les modes de vie actifs dans la population gĂ©nĂ©rale est capitale. Pour une contribution efficace du mĂ©decin Ă  la promotion de l’activitĂ© physique, cet article s’est destinĂ© Ă  actualiser une dĂ©marche systĂ©matique du conseil en activitĂ© physique simple et applicable en routine, aprĂšs une formation spĂ©cifique : la mĂ©thode des « 5A » Ă  savoir : « ApprĂ©cier » ; « Aviser » ; « AgrĂ©er » ; « Assister » ; « Arranger »

    Recommandations pour la pratique clinique : « Interventions pendant la pĂ©riode pĂ©rinatale ». Chapitre 1 Partie 2 : Effets bĂ©nĂ©fiques de l’activitĂ© physique maternelle durant la grossesse sur la santĂ© du fƓtus, du nouveau-nĂ© et de l’enfant

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    L’objectif de ce travail est de faire un Ă©tat des lieux des effets de l’activitĂ© physique maternelle pendant la grossesse sur la santĂ© de son enfant. Pendant les pĂ©riodes gravidiques et postnatales, l’activitĂ© physique maternelle a montrĂ© des effets favorables dans le contrĂŽle du risque de macrosomie, d’obĂ©sitĂ© et autres troubles cardio-mĂ©taboliques associĂ©s. MĂȘme si des Ă©tudes longitudinales chez l’humain sont encore nĂ©cessaires pour valider leur terme, ces effets ont Ă©tĂ© observĂ©s de façon cohĂ©rente dans les Ă©tudes animales. Un effet remarquable de l’activitĂ© physique maternelle est son rĂŽle positif sur la neurogenĂšse, le dĂ©veloppement du langage, la mĂ©moire et autres fonctions cognitives liĂ©es Ă  l’apprentissage

    Exercise in children and adolescents with diabetes

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    Adding anthropometric measures of regional adiposity to BMI improves prediction of cardiometabolic, inflammatory and adipokines profiles in youths: a cross-sectional study.

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    BACKGROUND: Paediatric research analysing the relationship between the easy-to-use anthropometric measures for adiposity and cardiometabolic risk factors remains highly controversial in youth. Several studies suggest that only body mass index (BMI), a measure of relative weight, constitutes an accurate predictor, whereas others highlight the potential role of waist-to-hip ratio (WHR), waist circumference (Waist C), and waist-to-height ratio (WHtR). In this study, we examined the effectiveness of adding anthropometric measures of body fat distribution (Waist C Z Score, WHR Z Score and/or WHtR) to BMI Z Score to predict cardiometabolic risk factors in overweight and obese youth. We also examined the consistency of these associations with the "total fat mass + trunk/legs fat mass" and/or the "total fat mass + trunk fat mass" combinations, as assessed by dual energy X-ray absorptiometry (DXA), the gold standard measurement of body composition. METHODS: Anthropometric and DXA measurements of total and regional adiposity, as well as a comprehensive assessment of cardiometabolic, inflammatory and adipokines profiles were performed in 203 overweight and obese 7-17 year-old youths from the Paediatrics Clinic, Centre Hospitalier de Luxembourg. RESULTS: Adding only one anthropometric surrogate of regional fat to BMI Z Score improved the prediction of insulin resistance (WHR Z Score, R(2): 45.9%. Waist C Z Score, R(2): 45.5%), HDL-cholesterol (WHR Z Score, R(2): 9.6%. Waist C Z Score, R(2): 10.8%. WHtR, R(2): 6.5%), triglycerides (WHR Z Score, R(2): 11.7%. Waist C Z Score, R(2): 12.2%), adiponectin (WHR Z Score, R(2): 14.3%. Waist C Z Score, R(2): 17.7%), CRP (WHR Z Score, R(2): 18.2%. WHtR, R(2): 23.3%), systolic (WHtR, R(2): 22.4%), diastolic blood pressure (WHtR, R(2): 20%) and fibrinogen (WHtR, R(2): 21.8%). Moreover, WHR Z Score, Waist C Z Score and/or WHtR showed an independent significant contribution according to these models. These results were in line with the DXA findings. CONCLUSIONS: Adding anthropometric measures of regional adiposity to BMI Z Score improves the prediction of cardiometabolic, inflammatory and adipokines profiles in youth

    Insight into physical activity in combating the infantile metabolic syndrome

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    Metabolic syndrome (MetS) is increasingly reported in children, mainly in the presence of overweight/obesity. From the most recent report, up to 60% of overweight and obese children can be affected by this syndrome. MetS acquired during childhood has been shown to track into adulthood, including its clinical complications, such as type 2 diabetes and cardiovascular diseases. Among the practical preventive and therapeutic measures to be taken in children, physical activity (PA) appears to be at least as efficient as the most adequate pharmacology. The current literature suggests that exercise programs based either on aerobic-or resistance-type exercises, or a combination of these 2 types of structured activity, may promote insulin sensitivity and weaken or suppress MetS in children. Furthermore, daily-living activities such as brisk walking were found to substantially reduce the risk of MetS among children. Regardless of their weight status, PA needs to be promoted among children as early as possible
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