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Energy-Aware Optimization Strategy for P-Time Labeled Petri Net Systems under Partial Observation
No full textInternational audienc
Estimation des années de vie pondérées par la qualité de vie(Quality Adjusted Life Years - QALYs) par modélisation conjointe: une étude de simulation
No full textInternational audienceBackground and objectives. Clinical trials investigators often chose patient survival as the primary outcome. However, a survival gain may not accurately reflect patients’ preferences if it comes at the expense of a deteriorated health-related quality of life (HRQoL).When HRQoL outcomes are considered, they are usually analyzed secondarily and separately from the survival outcome, which precludes the possibility of considering potential trade-offs between them. In contrast, Quality-Adjusted Life Years (QALYs) are a composite outcome that allows the two aspects to be considered simultaneously by weighting years of life by HRQoL indexes that reflect individual preferences (health utility scores). Hence, QALYs could be a practical primary outcome for assessing treatments efficacy.However, the estimation of QALYs still suffers several methodological pitfalls and usually relies on non-parametric approaches that require strong simplifying assumptions including linear interpolation between observations and independence between HRQoL and risk of death. This work aims to propose a sounder method for estimating QALYs using the shared random effects joint modelling framework.Material and methods. We first developed a shared random-effect joint model, the longitudinal health utility scores being considered through a mixed beta regression and the time-to-death through a proportional hazard Weibull model. We then proposed a method for estimating the number of QALYs using such a joint model. We finally compared its performances with the commonly used non-parametric method through a simulation study.We simulated a wide range of scenarios of clinical trials considering the presence and absence of treatment effect, 200 and 500 included patients, one and two health utility measurements per patient per year for three years, and three censoring rates: 0%, 10% and 30% at a three-year horizon. We also considered different data generation mechanisms resulting in good or bad model specification. Each scenario was simulated 1000 times and the treatment effect was estimated in terms of QALYs at a three-year horizon.Results. Our proposed method provided unbiased estimates of QALYs and significant improvements over the non-parametric approach when the joint model was well specified. This was particularly the case when a low number of repeated utility measurements per patient or a high censoring rate was simulated. The two methods performed poorly when simulating the risk of event with non-proportional hazards.Conclusions. We proposed a method based on joint modeling for estimating QALYs. We reported accurate estimations for clinical trials with moderate sizes when the model is well specified. However, we found the estimations to be sensitive to model misspecification. We are working to develop additional modelling tools and deliver an R package that will provide users with relevant modelling choices and allow them to accurately estimate QALYs in a wide range of situations. We hope this will encourage a larger use of QALYs in clinical trials and better consideration of patients’ preferences in medical decision-making
Carrières, celliers et maisons élitaires à Nogent-Le-Rotrou au XIIIe siècle
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La rivière et son réseau.: La participation numérique citoyenne, de l’alerte à la mobilisation environnementale
No full textNational audienceLa rivière et son réseau.La participation numérique citoyenne, de l’alerte à la mobilisation environnementale
Absence of percolation for infinite Poissonian systems of stopped paths
No full textInternational audienceThe state space of our model is the Euclidean space in dimension d = 2. Simultaneously, from all points of a homogeneous Poisson point process, we let grow independent and identically distributed random continuum paths. Each path stops growing at time t > 0 if it hits the trace of the other curves realized up until time t. Such dynamic is well-defined as long as the distribution of paths has a finite second moment at each time t > 0. Letting the time runs until infinity so that each path reaches its stopping curve, we study the connected property of the graph formed by all stopped curves. Our main result states the absence of percolation in this graph, meaning that each cluster consists of a finite number of curves. The assumptions on the distribution of paths are very mild, with the main one being the so-called 'loop assumption' which ensures that finite clusters (necessarily containing a loop) occur with positive probability. The main issue in this model comes from the long-range dependence arising from long sequences of causalities in the hitting/stopping procedure. Most methods based on block approaches fail to effectively address the question of percolation in this setting
Description d'un dispositif expérimental visant à étudier l'impact des stimuli olfactifs sur les réponses comportementales chez les moutons (Ovis aries), en mettant particulièrement l'accent sur la minimisation des biais expérimentaux grâce à une phase d'accoutumance
No full textIn sheep, the emotional valence of olfactory stimuli needs to be studied as olfaction is crucial for social and dietary preferences. To this end, it is necessary to evaluate the behavioural responses induced by olfactory stimuli (OS). These latter have often been explored with animals tested alone, in odorized versus nonodorized food choice tests or with constraining procedures. All these conditions are likely to induce emotional behaviours, which questions the specificity and reproducibility of behavioural responses induced by the OS. This study aimed to create an experimental setup for investigating the impact of OS on behavioural responses while addressing social and food resources and avoiding other confounding factors. Particularly, we focused on minimizing experimental bias through a habituation phase. To test our setup, we examined the consistency of behavioural responses measured in the control situation over time in adult ewes and lambs, by using principal component analysis. We found that the behavioural responses of individuals are similar over time and that the animals were not stressed by the experimental setup. Then, we concluded that it is adapted to explore the repulsive or attractive properties of the OS. Moreover, based on specific behaviours like vocalization, agitation, exploration, social contact, it could be possible to explore the emotional valence of OS.Chez le mouton, la valence émotionnelle des stimuli olfactifs doit être étudiée, car l'olfaction est cruciale pour les préférences sociales et alimentaires. À cette fin, il est nécessaire d'évaluer les réponses comportementales induites par les stimuli olfactifs (SO). Ces derniers ont souvent été explorés avec des animaux testés seuls, dans des tests de choix alimentaire entre aliments odorants et non odorants ou avec des procédures contraignantes. Toutes ces conditions sont susceptibles d'induire des comportements émotionnels, ce qui remet en question la spécificité et la reproductibilité des réponses comportementales induites par les SO. Cette étude visait à créer un dispositif expérimental permettant d'étudier l'impact des SO sur les réponses comportementales tout en tenant compte des ressources sociales et alimentaires et en évitant d'autres facteurs de confusion. Nous nous sommes particulièrement attachés à minimiser les biais expérimentaux grâce à une phase d'accoutumance. Pour tester notre dispositif, nous avons examiné la cohérence des réponses comportementales mesurées dans la situation contrôle au fil du temps chez des brebis adultes et des agneaux, en utilisant l'analyse en composantes principales. Nous avons constaté que les réponses comportementales des individus étaient similaires au fil du temps et que les animaux n'étaient pas stressés par le dispositif expérimental. Nous avons donc conclu qu'il était adapté pour explorer les propriétés répulsives ou attractives du SO. De plus, sur la base de comportements spécifiques tels que la vocalisation, l'agitation, l'exploration et le contact social, il pourrait être possible d'explorer la valence émotionnelle du SO
Deciphering mechanism of Rho-dependent transcription termination in Mycobacterium tuberculosis
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Want to protect the environment? Advocate for women! Analysis of the impact of women on environmental spending
No full textThis paper investigates whether gender plays a role in public spending decisions in the environmental field. We consider a sample of 27 European Union countries from 2003 to 2022. Using Ordinary Least Square estimator, we show that a 1 percentage point increase in the share of women in government is associated with a 0.9 percent increase in public environmental spending. this result is robust to the addition of control variables, changes in the variables used to capture environmental spending, the use of alternative estimators, and are not country-specific. Heterogeneity analysis shows that women in senior positions have the largest impact on environmental spending. Contrary to intuition, the main result does not depend on the political party's orientation. It holds true regardless of when women participate in decision-making. When environmental expenditures are categorized, the presence of women increases spending on environmental R&D and water conservation, but reduces spending on waste management