Dexamethasone Use and Mortality in Hospitalized Patients with Coronavirus Disease 2019: a Multicenter Retrospective Observational Study

International audienc

Modeling and control of electric hot water tanks : from the single unit to the group

Cette thèse s'intéresse au développement de stratégies de décalage de charge pouvant être appliquées à un parc de chauffe-eau Joule (CEJ).On propose une modélisation entrée-sortie du système que constitue le CEJ. L'idée est de concevoir un modèle précis et peu coûteux numériquement, qui pourrait être intégré dans un CEJ intelligent. On présente notamment un modèle phénoménologique multi-période d'évolution du profil de température dans le CEJ ainsi qu'un modèle de la demande en eau chaude. On étudie des stratégies d'optimisation pour un parc de CEJ dont la résistance peut être pilotée par un gestionnaire central. Trois cas de figures sont étudiés. Le premier concerne un petit nombre de ballons intelligents et présente une méthode de résolution d'un problème d'optimisation en temps discret. Puis, on s'intéresse à un parc de taille moyenne. Une heuristique gardant indivisibles les périodes de chauffe (pour minimiser les aléas thermo-hydrauliques) est présentée. Enfin, un modèle de comportement d'un nombre infini de ballon est présenté sous la forme d'une équation de Fokker-Planck.This thesis focuses on the development of advanced strategies for load shifting of large groups of electric hot water tanks (EHWT).The first part of this thesis is dedicated to representing an EHWT as an input-output system. The idea is to design a simple, tractable and relatively accurate model that can be implemented inside a low-power computing unit embedded in a smart EHWT, for practical applications of optimization strategies. It includes in particular a phenomenological multi-period model of the temperature profile in the tank and a realistic domestic hot water consumption model.The second part focuses on the design of optimal control strategies for a group of tanks. Three use-cases are studied. The first one deals with a small number of smart and controllable EHWT for which we propose a discrete-time optimal resolution method. The second use-case adresses a medium-scale group of controllable tanks and proposes a heuristic which keeps the heating period undivided to minimize thermo-hydraulic hazards. Finally, we present the modelling of the behavior of a infinite population of tanks under the form of a Fokker-Planck equation

Modélisation et contrôle des ballons d'eau chaude sanitaire à effet Joule : du ballon individuel au parc

This thesis focuses on the development of advanced strategies for load shifting of large groups of electric hot water tanks (EHWT).The first part of this thesis is dedicated to representing an EHWT as an input-output system. The idea is to design a simple, tractable and relatively accurate model that can be implemented inside a low-power computing unit embedded in a smart EHWT, for practical applications of optimization strategies. It includes in particular a phenomenological multi-period model of the temperature profile in the tank and a realistic domestic hot water consumption model.The second part focuses on the design of optimal control strategies for a group of tanks. Three use-cases are studied. The first one deals with a small number of smart and controllable EHWT for which we propose a discrete-time optimal resolution method. The second use-case adresses a medium-scale group of controllable tanks and proposes a heuristic which keeps the heating period undivided to minimize thermo-hydraulic hazards. Finally, we present the modelling of the behavior of a infinite population of tanks under the form of a Fokker-Planck equation.Cette thèse s'intéresse au développement de stratégies de décalage de charge pouvant être appliquées à un parc de chauffe-eau Joule (CEJ).On propose une modélisation entrée-sortie du système que constitue le CEJ. L'idée est de concevoir un modèle précis et peu coûteux numériquement, qui pourrait être intégré dans un CEJ intelligent. On présente notamment un modèle phénoménologique multi-période d'évolution du profil de température dans le CEJ ainsi qu'un modèle de la demande en eau chaude. On étudie des stratégies d'optimisation pour un parc de CEJ dont la résistance peut être pilotée par un gestionnaire central. Trois cas de figures sont étudiés. Le premier concerne un petit nombre de ballons intelligents et présente une méthode de résolution d'un problème d'optimisation en temps discret. Puis, on s'intéresse à un parc de taille moyenne. Une heuristique gardant indivisibles les périodes de chauffe (pour minimiser les aléas thermo-hydrauliques) est présentée. Enfin, un modèle de comportement d'un nombre infini de ballon est présenté sous la forme d'une équation de Fokker-Planck

Adaptive Strategies for The Open-Pit Mine Optimal Scheduling Problem

Within the mining discipline, mine planning is the component that studies how to transform the information about the ore resources into value for the owner. For open-pit mines, an optimal block scheduling maximizes the discounted value of the extracted blocks (period by period), called the net present value (NPV). However, to be feasible, a mine schedule must respect the slope constraints. The optimal open-pit block scheduling problem (OPBSP) consists, therefore, in finding such an optimal schedule. On the one hand, we introduce the dynamical optimization approach to mine scheduling in the deterministic case, and we propose a class of (suboptimal) adaptive strategies, the so-called index strategies. We show that they provide upper and lower bounds for the NPV, and we provide numerical results. On the other hand, we introduce a theoretical framework for OPBSP under uncertainty and learning

Association of Antihypertensive Agents with the Risk of In-Hospital Death in Patients with Covid-19

International audiencePurpose: The role of angiotensin receptor blockers (ARB), angiotensin-converting enzyme inhibitors (ACEi), or other antihypertensive agents in the case of Covid-19 remains controversial. We aimed to investigate the association between antihypertensive agent exposure and in-hospital mortality in patients with Covid-19.Methods: We performed a retrospective multicenter cohort study on patients hospitalized between February 1 and May 15, 2020. All patients had been followed up for at least 30 days.Results: Of the 8078 hospitalized patients for Covid-19, 3686 (45.6%) had hypertension and were included in the study. In this population, the median age was 75.4 (IQR, 21.5) years and 57.1% were male. Overall in-hospital 30-day mortality was 23.1%. The main antihypertensive pharmacological classes used were calcium channel blockers (CCB) (n=1624, 44.1%), beta-blockers (n=1389, 37.7%), ARB (n=1154, 31.3%), and ACEi (n=998, 27.1%). The risk of mortality was lower in CCB (aOR, 0.83 [0.70-0.99]) and beta-blockers (aOR, 0.80 [0.67-0.95]) users and non-significant in ARB (aOR, 0.88 [0.72-1.06]) and ACEi (aOR, 0.83 [0.68-1.02]) users, compared to non-users. These results remain consistent for patients receiving CCB, beta-blocker, or ARB as monotherapies.Conclusion: This large multicenter retrospective of Covid-19 patients with hypertension found a reduced mortality among CCB and beta-blockers users, suggesting a putative protective effect. Our findings did not show any association between the use of renin-angiotensin-aldosterone system inhibitors and the risk of in-hospital death. Although they need to be confirmed in further studies, these results support the continuation of antihypertensive agents in patients with Covid-19, in line with the current guidelines

Trends of exposure to fetotoxic drugs during the second or the third trimester for pregnancies starting between 2013 and 2019 in France.

The p-values indicate whether a statistically significant trend was observed between 2013 and 2019. A. Overall fetotoxic drugs. Overall fetotoxic drugs with topical NSAIDs and overall fetotoxic drugs without topical NSAIDs. Trends were significant for: all fetotoxic drugs (p−3), and all fetotoxic drugs without topical forms (p−3). B. Any fetotoxic drug. Trends were significant for: contraceptives (p−3), non-steroids anti-inflammatory drugs for systemic use (p−3), non-steroids anti-inflammatory drugs for topical use (p−3), sex hormones (p−3). C. NSAIDs for systemic use. Trends were significant for: acetylsalicylic acid (p−3), diclofenac (p−3), flurbiprofen (p−3). D. NSAIDs for topical use. Trends were significant for: diclofenac (p−3), ibuprofen (p−3), ketoprofen (p−3), niflumic acid (p−3). E. Sex hormone. Trends were significant for: clomifene (p−3), promestriene (p−3).</p

Maternal and pregnancy outcome characteristics among pregnancies exposed to at least one fetotoxic drug (sensitivity analysis without topical NSAIDs).

Maternal and pregnancy outcome characteristics among pregnancies exposed to at least one fetotoxic drug (sensitivity analysis without topical NSAIDs).</p

Maternal and pregnancy outcome characteristics (sensitivity analysis without topical retinoids and topical NSAIDs).

Maternal and pregnancy outcome characteristics (sensitivity analysis without topical retinoids and topical NSAIDs).</p

Maternal characteristics and pregnancy outcomes among pregnancies exposed to a fetotoxic drug.

Maternal characteristics and pregnancy outcomes among pregnancies exposed to a fetotoxic drug.</p

Trends of exposure to teratogenic drugs during the preconceptional period or the first trimester for pregnancies starting between 2013 and 2019 in France.

The p-values indicate whether a statistically significant trend was observed between 2013 and 2019. A. Overall teratogenic drugs. Overall teratogenic drugs with topical retinoids and overall teratogenic drugs without topical retinoids. Trends were significant for: all teratogenic drugs (p−3), and all teratogenic drugs without topical forms (p−3). B. Overall teratogenic drugs. Trends were significant for: acetazolamide (p−3), antineoplastic and immunomodulating (p−3), HMG Coa reductase inhibitors (p−3), treatment of affective disorders (p−3), vitamin K antagonists (p−3). C. Teratogenic antiepileptic drugs. Trends were significant for: carbamazepine (p−3), phenytoin (p−3). D. Drugs for affective disorders. Trends were significant for: divalproate (p−3) and valpromide (p−3). E. Antithyroid preparations. Trends were significant for: thiamazole (pF. Vitamin K antagonists. Trends were significant for: fluindione (p−3).</p