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Another L Makes It Better? Lagrange Meets LLL and May Improve BKZ Pre-Processing
No full textInternational audienceWe present a new variant of the LLL lattice reduction algorithm, inspired by Lagrange notion of pair-wise reduction, called L4. Similar to LLL, our algorithm is polynomial in the dimension of the input lattice, as well as in , whereis an upper-bound on the norm of the longest vector of the input basis. We experimentally compared the norm of the first basis vector obtained with LLL and L4 up to dimension 200. On average we obtain vectors that are up to 16% shorter. We also used our algorithm as a pre-processing step for the BKZ lattice reduction algorithm with blocksize 24. In practice, up to dimension 140, this allows us to reduce the norm of the shortest basis vector on average by 3%, while the runtime does not significantly increases. In 10% of our tests, the whole process was even faster.This paper has been awarded the “Code and Data Available” and “Results Reproduced” badges as recognition that the author(s) have followed reproducibility principles. Code and data that allow readers to reproduce the results in this paper are available at https://zenodo.org/records/13847623. Participation in the ALENEX artifact evaluation phase was optional and performed at the request of the author(s)
Natural Disasters and Bank Liquidity Creation in Sub-Saharan African Countries: Evidence from Banks Panel Data
No full textInternational audienceThis paper investigates the effects of natural disasters on bank liquidity creation in sub-Saharan African during the period 1988-2018. Using bank-level data from more than 30 countries, we find that natural disasters affect negatively the liquidity creation in the region. The cumulative effect over the three years following a disaster is economically significant, amounting to a total reduction of 4% in the average liquidity generated. This impact is mainly channeled through the asset-side activities of banks. We also find heterogeneous impact of natural disasters on bank liquidity creation based on the size of banks, the magnitude of disasters and the income level of countries. Moreover, these effects are mainly observed when disasters strike on a large-scale. On the contrary, there is no significant difference depending on whether or not the disaster is climatic in origin. Additional tests show that foreign ownership of banks as well as monetary policy change do not qualitatively alter our primary findings. These results support bank regulation policies taking into the specificities of banks operating in environments prone to frequent natural disasters. Specifically, we recommend that central banks implement targeted regulatory measures such as stress-testing or resilience programs. As natural disasters are likely to increase in the coming years due to climate change, we suggest that microprudential policies be further strengthened and adapted to incorporate climate change considerations
Advancing sustainable transportation: A feasibility study on EV green charging station with fuzzy control systems in France and the Philippines
No full textInternational audienceThe transition to Electric Vehicles (EVs) represents a sustainable approach to energy consumption and provides a tangible solution to addressing environmental concerns. Many countries are committed to an energy transition process, placing significant emphasis on energy sobriety and efficiency. Their objectives include widespread development of renewable energies while positioning themselves at the forefront of green technologies for renewable and low-carbon hydrogen production. Additionally, investments are being made to facilitate the transition to clean vehicles. This paper introduces a feasibility study focused on developing charging stations (CSs) powered by Renewable Energy Sources (RESs) for EVs, with a specific emphasis on the French and Philippines contexts, aiming to contribute to the ongoing shift towards sustainable transportation. In addition, a fuzzy logic approach, particularly type 2 fuzzy logic, is utilized in this work in order to control the DC bus voltage and optimize power tracking from the RESs. A simulation example is provided to show the applicability of this study purpose
Differential Games for a Mixed ODE-PDE System
No full textInternational audienceMotivated by a vaccination coverage problem, we consider here a zero-sum differential game governed by a differential system consisting of a hyperbolic partial differential equation (PDE) and an ordinary differential equation (ODE). Two players act through their respective controls to influence the evolution of the system with the aim of minimizing their objective functionals F_1 and F_2 , under the assumption that F_1 + F_2 = 0. First we prove a well posedness and a stability result for the differential system, once the control functions are fixed. Then we introduce the concept of non-anticipating strategies for both players and we consider the associated value functions, which solve two infinite-dimensional Hamilton-Jacobi-Isaacs equations in the viscosity sense
Fully guaranteed and computable error bounds on the energy for periodic Kohn-Sham equations with convex density functionals
No full textInternational audienceIn this article, we derive fully guaranteed error bounds for the energy of convex nonlinear mean-field models. These results apply in particular to Kohn-Sham equations with convex density functionals, which includes the reduced Hartree-Fock (rHF) model, as well as the Kohn-Sham model with exact exchange-density functional (which is unfortunately not explicit and therefore not usable in practice). We then decompose the obtained bounds into two parts, one depending on the chosen discretization and one depending on the number of iterations performed in the self-consistent algorithm used to solve the nonlinear eigenvalue problem, paving the way for adaptive refinement strategies. The accuracy of the bounds is demonstrated on a series of test cases, including a Silicon crystal and an Hydrogen Fluoride molecule simulated with the rHF model and discretized with planewaves. We also show that, although not anymore guaranteed, the error bounds remain very accurate for a Silicon crystal simulated with the Kohn-Sham model using nonconvex exchangecorrelation functionals of practical interest
Connaissances et habitudes de vie des collégiens de la région Hauts-de-France en matière de prévention de l’obésité
No full textIntro : Obesity in teenagers represents a major public health issue, especially in Hauts-de-France where it remains particularly high. It is considered to be the results of complex interactions between nutrition, physical activity, screen time and sleep quality. Thus, our main objective was to determine whether middle school students from Hauts-de-france were aware of established food recommandations to prevent obesity and whether they were applied on their everyday lives. Materials and methods : To this end, we led an observational study including 586 students from Somme and Pas-de-Calais regions from urban and rural origins. An anonymous quizz was distributed to assess knowledge and habits of the participants in 4 domains : nutrition, physical activity, screen time and sleep quality. Results: A third of the students does not take breakfast. The recommandation regarding 5 fruits and vegetables per day is known by 63% of the participants but remains poorly applied. Indeed, 37% do not eat vegetables during lunches. Of the 60% of the students that are enrolled in sports club, 1/3 does not follow the recommended daily hour of physical activity. Regarding daily screen time, around 3/4 of the students exceed the recommended 2 hours with 1/4 exceeding 6 hours. In addition, we show a significant correlation between high body mass index and sleep deprivation. Finally, 88% of the students identified obesity as a source of comorbidities. Conclusion : Obesity in teenagers is multifactorial. Prevention must be global and should include healthy food habits, physical activity, good sleep quality and low screen time. Care providers have a key role in preventing obesity and following patients in order to help them establishing proper habits.Introduction : l’obésité de l’adolescent constitue un problème majeur de santé publique, particulièrement dans la région Hauts-de-France où sa prévalence reste élevée. Elle résulte d’interactions complexes entre alimentation, activité physique, temps d’écran et sommeil. Ainsi notre objectif principal est de déterminer si les adolescents scolarisés dans la région Hauts-de-France connaissent les recommandations nutritionnelles en termes de prévention de l’obésité et s’ils les appliquent au quotidien. Matériels et méthodes : pour cela, une étude observationnelle transversale a été menée auprès de 586 collégiens de 5e et de 3e de la Somme et du Pas-de-Calais, issus de milieux urbains et ruraux. Un questionnaire auto-administré anonyme a exploré les connaissances et pratiques des élèves dans quatre domaines : alimentation, activité physique, écrans et sommeil. Résultats : un tiers des élèves ne prend pas de petit-déjeuner. La recommandation « 5 fruits et légumes par jour » est connue par 62,8 %, mais peu appliquée. En effet, 37% ne consomment pas de légumes lors des principaux repas. Si 60 % sont inscrits en club sportif, près d’un sur trois ne pratique pas l’heure quotidienne recommandée. Près de ¾ des élèves ont une consommation d’écran excédant les deux heures d’écrans par jour recommandées et un quart dépasse les six heures quotidiennes. Il existe une corrélation significative entre un IMC plus élevé et un déficit de sommeil. Enfin, 88 % des élèves identifient l’obésité comme source de complications. Conclusion : l’obésité adolescente est multifactorielle. La prévention doit être globale, intégrant alimentation, activité physique, sommeil et écrans. Le médecin généraliste a un rôle clé dans le dépistage et l’accompagnement, pour aider à mettre en place les recommandations connues mais non appliquées
Optimisation du mode de commande de medicaments en dotation : impact sur les demandes urgentes et satisfaction des soignants
No full textLa gestion du circuit du médicament est une des missions attribuées au pharmacien hospitalier. De son aspect clinique à son aspect logistique, le pharmacien est garant de sa bonne application afin de sécuriser la prise en charge médicamenteuse du patient. Les instances françaises sont de plus en plus impliquées dans la révision et l’évaluation de ce circuit : certification des établissements de santé, études mesurant les évènements indésirables associés aux soins, rapports présentant les impacts organisationnels du circuit du médicament,… Dans la but d’harmoniser et de faciliter le mode de commande de médicaments en dotation, la pharmacie du CHU Amiens-Picardie a décidé de modifier le protocole de demandes passant de l’utilisation du logiciel DxPharm® à e-order® à partir de Novembre 2024. L’objectif de ce travail est d’apprécier l’impact de ce changement sur le circuit des demandes urgentes mais aussi de recueillir la satisfaction des soignants. L’étude a montré que les soignants adhèrent au nouveau logiciel e-order® pour la commande planifiée. Aucun impact délétère n’a pu être observé sur le circuit urgent. Au contraire, le nombre de lignes urgentes pour des médicaments en dotation a diminué. L’analyse du circuit urgent a permis de mettre en évidence trois points majeurs : la majorité des lignes urgentes sont saisies en période de garde, les principaux services de soins demandeurs ont été identifiés, ainsi que les médicaments les plus commandés. Les soignants sont plutôt satisfaits de ce changement malgré quelques problèmes entravant la bonne utilisation d’e-order
La maladie de Lyme : diagnostic et complications d’une maladie en recrudescence
No full textLa maladie de Lyme est une zoonose dont l’incidence est croissante ces dernières années. Après avoir présenté les généralités de la pathologie, son diagnostic clinique et les traitements actuellement disponibles, ce travail a pour but de mettre en avant les difficultés de poser un diagnostic ainsi que les complications auxquelles doivent faire face les patients pris en charge trop tardivement. Un autre axe de réflexion de ce travail aborde la problématique du réchauffement climatique et ses effets sur le développement de la pathologie, via le vecteur qu’est la tique. Pour bien comprendre ces évolutions il faut donc bien comprendre le vecteur. Enfin, le rôle du pharmacien d’officine n’est pas à négliger : il est en première ligne pour prodiguer les bons conseils de prévention, et accompagne les patients déjà sous traitement
Élaboration d’un score pronostique prédictif de douleurs aiguës intenses en postopératoire de chirurgie abdominale programmée
No full textIntroduction: Intense acute postoperative pain remains frequent after abdominal surgery and may lead to negative outcomes by delaying recovery, increasing the risk of complications and increasing the risk of chronic postsurgical pain (CPSP). The aim of this study was to develop a simple and clinically applicable risk score to predict intense postoperative pain after abdominal surgery. Methods: This retrospective, observational study was conducted at Amiens University Hospital from October 2023 to June 2024. Among 1341 patients undergoing elective abdominal surgery, 400 were included. The primary outcome was intense postoperative pain (Numeric Rating Scale (NRS) ≥ 6/10) within the first 48 postoperative hours. A predictive risk score was developed using the method described by Sullivan et al., followed by internal validation performed on a sample of the cohort. Results: Four independent predictors were associated with its occurrence : digestive surgery (OR 4.47 ; 95% CI : 2.60-7.89), preoperative chronic pain (OR = 3.98 ; 95% CI : 1.30-14.02), age younger than 40 years (OR = 2.47 ; 95% CI : 1.11-5.63) and active smoking (OR = 2.45 ; 95% CI : 1.29-4.74). The resulting score (0-6) showed a progressive increase in predicted risk with higher values. In internal validation, discriminatory performance was acceptable (AUC 0.71 ; 95% CI : 0.62-0.80) with good calibration. Conclusion: Our score identified high-risk patients for intense postoperative pain after abdominal surgery. Application of this score could help to personalize analgesic strategies and improve postoperative pain control. Yet, external validation remains necessary to confirm its performance.Introduction : La douleur post opératoire (DPO) aigue intense reste fréquente après chirurgie abdominale et compromet la récupération en augmentant le risque de complication et de chronicisation douloureuse. L’objectif de cette étude était d’élaborer un score simple, utilisable en pratique clinique pour prédire la survenue de DPO intenses après chirurgie abdominale. Méthodes : Il s’agit d’une étude observationnelle rétrospective menée au CHU Amiens-Picardie d’octobre 2023 à juin 2024. Parmi 1341 patients opérés d’une chirurgie abdominale programmée, 400 ont été inclus. La variable à prédire était la survenue d’une DPO intense (échelle numérique (EN) ≥ 6/10) dans les 48 heures postopératoire. Un score prédictif a été construit selon l’approche de Sullivan, puis une validation interne a été réalisée sur un échantillon de la cohorte. Résultats : Quatre facteurs indépendants étaient associés à la survenue de DPO : chirurgie digestive (OR 4,47 ; IC95% : 2,60-7,89), douleur chronique préopératoire (OR = 3,98 ; IC95% : 1,30-14,02), âge inférieur à 40 ans (OR = 2,47 ; IC95% : 1,11-5,63) et tabagisme actif (OR = 2,45 ; IC95% : 1,29-4,74). Le score obtenu (de 0 à 6 points) montrait une augmentation progressive du risque de DPO intense avec sa valeur. En validation interne, la performance discriminative était acceptable (AUC 0,71 ; IC95% : 0,62-0,80) avec une calibration satisfaisante. Conclusion : Notre score a permis d’identifier dans notre cohorte les patients à haut risque de DPO intenses après chirurgie abdominale. Son utilisation pourrait contribuer à personnaliser la stratégie antalgique et à améliorer le contrôle de la DPO. Une validation externe reste néanmoins nécessaire pour confirmer sa performance
Consensus on the Management of Anesthetic Agents During Digestive Motility Measurements and Proposal of a Standardized Protocol for Anesthesia (French Neuro Gastroenterology Group GFNG and Committee of Anesthetic French Experts)
No full textInternational audienceABSTRACT Introduction Techniques for measuring digestive motility are becoming increasingly precise and enable therapeutic interventions. However, while most of these interventions require general anesthesia, there is limited data on the impact of anesthetic agents on these measurements, and no standardized anesthesia protocol currently exists to guide such procedures. Our working group carried out two Delphi processes involving experts in neurogastroenterology and anesthesiology to reach a consensus on which drugs affect these measurements and to establish an anesthesia protocol. Method Two expert groups were formed, comprising 13 neurogastroenterology experts from the French Neuro‐Gastroenterology Group (GFNG) and 15 full‐ or associate professors in anesthesia and intensive care. The first Delphi process involved the neurogastroenterologists and aimed to identify which anesthetic drugs influenced digestive pressure measurements. The second Delphi process, involving anesthetists, sought to develop an anesthesia protocol. Each expert indicated their level of agreement with each statement using a 6‐point Likert scale. A statement was endorsed when at least 80% of experts agreed with it. The strength of evidence for each statement was evaluated using the GRADE system. Results The Delphi process with neurogastroenterologists was conducted over three rounds and ultimately resulted in 91 amendments. The second Delphi process with anesthetists took place over two rounds and included 28 amendments, leading to the development of an anesthesia protocol. Conclusion To our knowledge, this work is the first to establish an expert consensus on anesthetic agents that can affect digestive motility measurements and to propose an anesthesia protocol that accounts for the needs of neurogastroenterologists