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Evidence for the absence of a relationship between inflammation and cognition in a cohort of 1565 individuals with bipolar spectrum disorders: a Bayesian analysis of network
No full textInternational audiencePrevious studies have reported variable associations between peripheral inflammatory markers and cognitive functioning in individuals with bipolar spectrum disorders (BSD), with some identifying significant links and others finding no relationship. Such inconsistencies raise important questions about the role of inflammation in cognitive impairment among individuals with BSD. This study aims to investigate the relationship between peripheral inflammatory markers and cognitive function in a clinical sample of individuals with BSD using a Bayesian network analysis framework. We analyzed data from a large cohort (n = 1565) focusing on hsCRP and a subsample (n = 249) that included concurrent assessments of additional cytokines including Interleukin-6 and Tumor Necrosis Factor-alpha. A Bayesian approach was utilized to quantify uncertainty regarding the presence or absence of associations between inflammation and cognitive function. Our findings revealed no significant associations between inflammatory markers and cognitive performance in both samples. Strong evidence was found supporting the absence of association, with network analysis indicating distinct clusters for cognitive and inflammatory variables, suggesting they function as independent constructs with limited interactions. In our clinical sample of individuals with BSD, our findings do not support a direct association between some inflammatory markers and cognition, aligning with studies that found minimal or no associations. Our study emphasizes the importance of utilizing Bayesian methods to assess these relationships rigorously and suggests further exploration of individual differences and subgroup effects in future research
Hybrid antioxidant based on exfoliated layered double hydroxides nanosheets with improved thermal stabilizing effects for polypropylene
No full textInternational audienceAn antioxidant (AO) agent, 3-(3,5-ditertbutyl-4-hydroxyphenyl) propionate anions (DBHP), intercalated between layered double hydroxides (DBHP-LDH) was prepared by coprecipitation method and then a part was delaminated in toluene to form exfoliated DBHP-LDH nanosheets. Both types of DBHP-LDH compositions, powder and exfoliated nanosheets were characterized by XRD, SEM and TEM, and subsequently incorporated into polypropylene (PP) as AO filler to improve the thermal stability of PP. The addition of DBHP-LDH affected the crystallization and melting behaviour as well as transmittance of PP, giving rise to its crystallinity improved but its transparency reduced. It was found that by incorporating either DBHP-LDH powder or exfoliated DBHP-LDH nanosheets the thermal decomposition temperatures and thermal aging resistance of PP were enhanced. Interestingly, between the two hybrid systems, it is however the exfoliated DBHP-LDH nanosheets that showed a better stabilizing effect for PP. This is attributed to the better dispersion regarding the exfoliated DBHP-LDH nanosheets, thus providing a more efficient radical scavenging capability. Even with its pronounced interface between PP chains and highly exposed nanosheets, about 30 % of DBHP was released from the exfoliated DBHP-LDH/PP compared to about 20 % DBHP migrated out of the conventional DBHP-LDH/PP films after 132 h test. This shows that the organic AO agent is well tethered to hydroxyl-bearing LDH nanosheets, thus opening new route to design functionalized filler for polymer from exfoliated LDH hybrid layers
Identifying codes in graphs of given maximum degree: Characterizing trees
No full textInternational audienceAn of a closed-twin-free graph is a dominating set of vertices of such that any two vertices in have a distinct intersection between their closed neighborhoods and . It was conjectured that there exists an absolute constant such that for every connected graph of order and maximum degree , the graph admits an identifying code of size at most . We provide significant support for this conjecture by exactly characterizing every tree requiring a positive constant together with the exact value of the constant. Hence, proving the conjecture for trees. For (the graph is a path or a cycle), it is long known that suffices. For trees, for each , we show that suffices and that is required to have a positive value only for a finite number of trees. In particular, for , there are 12 trees with a positive constant and, for each , the only tree with positive constant is the -star. Our proof is based on induction and utilizes recent results from [F. Foucaud, T. Lehtilä. Revisiting and improving upper bounds for identifying codes. SIAM Journal on Discrete Mathematics, 2022]. We remark that there are infinitely many trees for which the bound is tight when ; for every , we construct an infinite family of trees of order with identification number very close to the bound, namely \left( \frac{Δ-1+\frac{1}{Δ-2}}{Δ+\frac{2}{Δ-2}} \right) n > (\frac{Δ-1}Δ ) n -\frac{n}{Δ^2}. Furthermore, we also give a new tight upper bound for identification number on trees by showing that the sum of the domination and identification numbers of any tree is at most its number of vertices
Weakly-sparse and strongly flip-flat classes of graphs are uniformly almost-wide
No full textInternational audienceIn this work we take a step towards characterising strongly flip-flat classes of graphs. Strong flip-flatness appears to be the analogue of uniform almost-wideness in the setting of dense classes of graphs. We prove that strongly flip-flat classes of graphs that are weakly sparse are indeed uniformly almost-wide
New opportunities for rare charm from decays
No full textInternational audienceWe analyze the potential of rare charm decays as probes of new physics at a high-luminosity flavor facility operating at the pole, such as the FCC-ee or CEPC. In particular, we identify clean null-test observables in and in polarized decays with . Complementarity with the LHC and HL-LHC flavor programs arises from the characteristic features of a Tera- environment: the capability to study missing-energy modes and charm production with significant polarization. We improve the theoretical description of decays and work out the phenomenology of polarization-induced null-test observables in decays. In regions of dilepton mass near the resonance, polarization asymmetries can reach for muons and for electrons times the polarization. We also point out synergies between the dineutrino and the dilepton modes using the SMEFT framework of heavy new physics. Using the IDEA detector concept at FCC-ee, we find in simulation studies that dineutrino branching fractions as low as can be probed, which reaches well into the parameter space of new physics, and also allows for discrimination of lepton flavor structures. Furthermore, the measurement of asymmetries in at will be possible. Similar sensitivities are expected for dielectron final states, although robust predictions will require further dedicated studies
One pot-synthesis, crystal structure , DFT studies, in silico molecular docking studies of Novel Mannich bases from p-methoxythymol
No full textInternational audienceThis work was designed to synthesize Mannich base compounds starting from naturally occurring p-methoxythymol. This end was isolated from the wood of Tetraclinis Articulata and involved in a three-component Mannich reaction with formaldehyde and various secondary acyclic and cyclic amines. All targeted compounds 1a-e were fully identified based on their 1H and13C Nuclear magnetic resonance (NMR) spectral data. The structures of 1a, 1d and 1e were confirmed by X-ray diffraction (XRD) analysis showing that the molecules are associated by C—H···O and C—H···π interactions forming a supramolecular network. The Hirshfeld surface indicate that the H···H (75.5–81.5 %) interactions are significantly higher than the others interactions. Further, density functional theory calculations have been used to analyze the electronic and geometric frontier molecular orbital and molecular electrostatic map analyses of the compounds to predict the reactive site. Molecular docking studies performed against apoptotic and anti-apoptotic proteins BAX, BCL2, and Caspase-3 demonstrated that compound 1e had the highest binding affinity of -24.0, -24.5, and -24.8 kJ/mol than the piperine (-20.2, -28.4, -27.6 kJ/mol) which was used as standard inhibitor. At the end, in silico Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) predictions found all compounds to have a favorable drug-like profile, predicted Central Nervous System (CNS) permeability, and low toxicity. Conclusively, the results suggest that the newly synthesized Mannich base derivatives of p-methoxythymol have promising applications as lead compounds for anticancer drug development
GATE 10 Monte Carlo particle transport simulation: II. Architecture and innovations
No full textInternational audienceOver the past years, we have developed GATE version 10, a major re-implementation of the long-standing Geant4-based Monte Carlo application for particle and radiation transport simulation in medical physics. This release introduces many new features and significant improvements, most notably a Python-based user interface replacing the legacy static input files. The new functionality of GATE version 10 is described in the part 1 companion paper (Sarrutet al2025 arXiv:2507.09842). The development brought significant challenges. In this paper, we present the solutions that we have developed to overcome these challenges. In particular, we present a modular design that robustly manages the core components of a simulation: particle sources, geometry, physics processes, and data acquisition. The architecture consists of integrated C++ and Python codes. This framework allows for the precise, time-aware generation of primary particles, a critical requirement for accurately modeling positron emission tomography, radionuclide therapies, or prompt-gamma timing systems. We present how GATE 10 handles complex Geant4 physics settings while exposing a simple interface to the user. Furthermore, we describe the methodological solutions that facilitate the seamless integration of advanced physics models and variance reduction techniques. The architecture supports sophisticated scoring of physical quantities (such as Linear Energy Transfer and Relative Biological Effectiveness) and is designed for multithreaded execution. The new user interface allows researchers to script complex simulation workflows and directly couple external tools, such as artificial intelligence models for source generation or detector response. By detailing these architectural innovations, we demonstrate how GATE 10 provides a more powerful and flexible tool for research and innovation in medical physics. This paper is not intended to be a developer guide. Its purpose is to share with the research community in-depth explanations of our development effort that made the new GATE 10 possible
Towards coupling 3D printing and the glycation reaction to texturize food for people with oral frailty: A review.
No full textInternational audienceThe world's aging population and the growing number of people suffering from oral disorders require the design of texturally and nutritionally adapted and personalized foods. New tools, such as 3D printing, now make it possible to explore textures and shapes that can enhance food palatability, chewability and swallowability. However, it is possible to go a step further by combining the glycation reaction with the printing process to design foods with improved functional and structural properties without adding chemical texturize-modifying agents. This review presents, discusses and evaluates the potential benefit of combining 3D food printing with the glycation reaction to texturize foods for people with oral frailty. We use the existing literature to explain the mechanisms involved in these two approaches and the major role of mastication in food choice to help inform the design of tastier new foods that are beneficial to health and contain fewer additives, taking into account the formation of potentially deleterious compounds. We also present helpful modeling tools not only for food design but also for process optimization
Psychoactive substances in a general forensic autopsy population: prevalence and associations with cause and manner of death
No full textInternational audienceThis study investigated the prevalence of opioid-related deaths within a general forensic population. Conducted as a prospective, single-center, observational study, it included all subjects autopsied in forensic medicine in the Auvergne region (France). The primary objective was to assess the prevalence of opioid-related deaths in forensic cases, with secondary objectives including evaluating the prevalence of non-opioid psychoactive substances, screening blood alcohol levels, and profiling victims.Among 422 subjects who died from unnatural causes, the leading causes of death were suicide (51.7%) and accidents (39.8%). Opioids were detected in 24.2% of individuals, but directly involved in only 17.6% of those cases. Substances, including alcohol, were found in more than two-thirds of deaths (71.2%). Three distinct victim profiles were identified: middle-aged and elderly males dying by violent suicide; young males dying by fatal traffic accidents, often under the influence of alcohol and drugs of abuse; and young males dying by homicides, frequently under the influence of alcohol, opioids and toxic or lethal drugs.The study provides data on the prevalence and role of opioids, alcohol, and non-opioid psychoactive substances in forensic deaths. While opioids were directly implicated in a limited number of cases, the study highlights the significant presence of alcohol and other non-opioid psychoactive substances in unnatural deaths. These findings, suggest that further research with a larger study area and more cases would be beneficial
L’évaluation dans les dispositifs hybrides de l’enseignement supérieur : quelles méthodes et quels outils ?
No full textInternational audienceCette recherche a été menée dans le cadre du projet HyPES, qui vise à étudier les dispositifs hybrides de formation dans l'enseignement supérieur. Elle s'appuie principalement sur les résultats d'un précédent projet européen, HySUP (Burton et al., 2011 ; Deschryver & Charlier, 2012 ), qui a développé une typologie des systèmes hybrides basée sur cinq dimensions principales :-L’articulation entre présence et distance: elle correspond à l’organisation spatio-temporelle des activités d'enseignement et d’apprentissage (accès, lieu, temps, rythme) selon l’approche pédagogique et les types d’activité. -La médiatisation : représente le processus par lequel les outils numériques sont intégrés dans un dispositif de formation (Peraya, 2008) selon leurs spécificités, le public et les objectifs d’apprentissages. Il existe deux approches pour aborder cette médiatisation ; soit une entrée par les fonctions médiatisées (information, gestion, production, interaction, soutien, évaluation, métaréflexion et awarness), soit une entrée par les objets médiatisés au sein du système d'enseignement (qui peuvent être un objet spécifique, une séquence ou l'ensemble du dispositif). La médiatisation désigne donc le rôle et l'importance que l'enseignant ou le formateur attribue aux outils numériques au sein du dispositif de formation lors de sa phase de conception (Noben, 2024).-La médiation : c’est le processus de transformation que les outils numériques produisent sur les comportements humains, à travers lesquels le sujet interagit avec le monde, avec des objets, d'autres sujets ou même avec lui-même (Peraya & Peltier, 2012). Il existe plusieurs formes de médiation, telles que la médiation (semi-)cognitive, épistémique, réflexive, relationnelle, posturale ou praxéologique.-L’ouverture : correspond au degré de liberté donné à l’étudiant au sein de la formation. Par exemple, la possibilité pour les étudiants de choisir les modalités pratiques d'organisation, les rythmes, l'utilisation de ressources externes, les méthodes d'enseignement, les objectifs...-L’accompagnement : c’est le type de soutien apporté aux étudiants (méthodologique, métacognitif, cognitif) et le type de personnes qui apportent ce soutien (étudiant, enseignant…). Cela inclut également le degré de présence (socio-cognitive, socio-affective et pédagogique) et les modalités de soutien (réactives ou proactives).Ce cadre théorique a été enrichi par des recherches visant à développer un modèle intégratif pour aborder la dynamique complexe de la co-construction d'environnements d'apprentissage hybrides (Charlier & Peltier, 2024). Ces auteurs soulignent la nécessité de réviser les dimensions afin d'identifier les types de dispositifs actuels (« conception de l'apprentissage ») à travers une étude empirique. Elles suggèrent de développer et d'itérer une enquête à grande échelle, le premier questionnaire devant nécessairement être long, car il aborde non seulement les cinq dimensions principales décrites ci-dessus, mais aussi deux dimensions complémentaires. La première est l'évaluation de l'apprentissage, qui comprend la perception des objectifs d'apprentissage, l'adéquation des activités mises en place pour atteindre les objectifs, l'adéquation des formes d'évaluation par rapport aux objectifs et le soutien apporté à l'apprentissage grâce aux feedbacks. La seconde est l’intégration des perceptions des étudiants dans l’étude des dispositifs hybrides.Deux modifications importantes ont donc été apportées par rapport au premier cadre. Le point de vue des étudiants a été intégré dans la recherche, c'est-à-dire leur positionnement sur les dimensions évaluées par les enseignants, à travers un questionnaire spécifique. De plus, un suivi longitudinal de ceux-ci est effectué afin de percevoir l’évolution de leurs Environnements Personnels d’Apprentissage (EPA) dans le temps au sein d’un même dispositif et dans différents cours. Pour l'évaluation, les modalités et les outils (épreuves écrites, épreuves orales, productions écrites, travaux réflexifs, SAE, etc.) ainsi que leurs finalités (évaluation sommative, certification, formative, prédictive, normative, etc.) sont abordés à la fois dans le questionnaire à destination des enseignants et dans celui adapté pour les étudiants.L'étude de ce dernier aspect, l'évaluation de l'apprentissage dans les dispositifs hybrides de formation de l’enseignement supérieur, est au centre de cette communication. Les réponses de plus de 100 enseignants de l'enseignement supérieur à un questionnaire en ligne ont été analysées. La manière dont les enseignants conçoivent l'évaluation dans les dispositifs hybrides et les outils numériques utilisés à cette fin seront décrits.Sur la base du nouveau cadre de référence enrichi, une nouvelle typologie des systèmes de formation hybrides sera établie selon une méthodologie similaire à celle utilisée dans le projet HySup (Burton et al., 2011). L'aspect évolutif des dispositifs hybrides à différents stades de développement sera ensuite étudié selon les dimensions du cadre de référence enrichi. Pour ce faire, le concept d'EPA (Felder, 2019) sera principalement étudié. Les travaux de Vermunt et Verloop (1999) et leurs concepts de friction et d'alignement aideront à caractériser les changements observés dans les dispositifs en lien avec les perceptions des étudiants et des enseignants.L'objectif final est de développer un modèle de développement et d'évolution des dispositifs hybrides afin d'évaluer leur qualité à travers leurs niveaux de développement respectifs