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From physics-informed guidance to progressive distillation: A dual-stage diffusion framework for brain MRI super-resolution
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Convergence vers les lois stables pou des produits de matrices aléatoires
No full textUnder reasonable algebraic assumptions and under an infinite second order moment assumption, we show that the logarithm of the norm (log-norm) of a product of random i.i.d. matrices with entries in or in any other local field satisfies a generalized Central Limit Theorem (GCLT) in the sense of Paul Lévi.The proof is based on a weak law of large number for the difference between the log-norm of the product of the first matrices and the sum of their log-norms. This weak law of large numbers morally says that behaves like a sum of i.i.d. random variables that have a finite moment of order as long as the log-norm of each matrices has a finite moment of order q for a given .This gain of moment is the central result of the present paper and is based on the construction of pivotal times. Moreover, these results admit a nice higher rank extension when one looks at the full Cartan projection instead of the log-norm.Sous de hypothèses algébriques raisonnables et une condition de moment d'ordre infini, on démontre que le logarithme d'un produit de matrices aléatoires indépendantes et de même loi, à coefficients réelles ou dans un corps localement compact, satisfait un théorème central limite généralisé au sens de Lévi.La preuve fait intervenir une loi faible des grands nombres pour la différence entre le log de la norme du produit de matrices et la somme de leurs log-normes. Cette loi faible des grand nombres diten gros que se comporte comme une somme de variables aléatoires indépendantes dont la loi commune a un moment d'ordre fini là où le log-norme de chacune des matrices a un moment d'ordre fini pour un certain q > 0.Ce gain de moment est central dans le résultat du présent article et est obtenu via la construction de temps pivots. De plus, ces résultats admettent une généralisation en rang supérieur dès qu'on regarde la projection de Cartan totale au lieu du log-norme
Extraction automatique des néologismes en chinois et en vietnamien (2015–2025)
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Short-term immobilization impairs pointing direction programming and early motor control processes
No full textInternational audienceShort-term limb immobilization is a valuable method for studying the contribution of proprioception since it temporarily reduces sensory and motor inputs. While several studies have shown that immobilization impairs cognitive and sensorimotor processes, none have yet demonstrated how it could specifically impact the programming of movement direction. Here, participants (N = 32) made uncorrected pointing movements toward five visual targets located in different directions − but requiring constant amplitude − without benefiting from any visual feedback on the hand. Pointing was performed on two consecutive days by Control and Immobilized participants, the latter of whom had worn a splint on the right arm during this 24 h period. Results showed that immobilization increased the duration of movement planning (i.e., longer reaction time) necessary to specify hand-path direction. A greater counterclockwise directional bias was observed at peak acceleration in the Immobilized group and persisted until the uncorrected movement offset. These results suggest that immobilization impacts direction programming as well as early motor control processes. We argue that proprioception deprivation impairs the perception of limb position, leading to both slower and less accurate motor command selection. Overall, we interpret that the lack of proprioceptive feedback and efference copies may influence the accuracy of movement planning after 24 h of immobilization, possibly reflecting changes in processes related to internal model mechanisms
Clinical outcomes of addictive disorders six months after ADHD Diagnosis: Insights from the START study
No full textInternational audienceIntroductionAttention-Deficit/Hyperactivity Disorder (ADHD) is overrepresented in patients with addictive disorders but remains underdiagnosed. This comorbidity complicates clinical presentations and worsens prognosis. We aimed to evaluate addictive disorder outcomes six months after ADHD diagnosis in patients undergoing addiction treatment and to identify factors associated with a favorable outcome. Secondary objectives explored patient characteristics and therapeutic strategies.MethodThe START study (Study on the Treatment of ADHD and addiction comorbidity: a ReTrospective analysis of medical records) was an observational, retrospective analysis of electronic medical records from patients recently diagnosed with ADHD using the DIVA. Included patients had either substance use disorders (SUD) or behavioral addictions (eating, sex, gambling, gaming/screen use, shopping, and physical exercise), with diagnoses established by the referring physician according to clinical judgment, and attended at least two consultations six months apart. Descriptive analyses were conducted for the total sample and by clinical outcome, followed by multivariate logistic regression to identify predictors of improvement.ResultsTobacco and cannabis use disorders were the most common (61.3 % each). Psychiatric comorbidities were frequent (lifetime 84.6 %, current 34.1 %). Methylphenidate initiation was delayed in 29 % of cases, primarily due to current psychiatric comorbidities or ongoing addiction. Improvement in addictive disorders was observed in 61.3 % of patients. Favorable outcomes were associated with older age (OR = 1.13, 95 % CI [1.04–1.23], p = 0.006) and living as a couple (OR = 3.84, 95 % CI [1.10–13.42], p = 0.035), whereas poorer outcomes were associated with the ADHD combined presentation (reference group), compared with the predominantly inattentive and hyperactive/impulsive presentations (OR = 0.16, 95 % CI [0.03–0.90], p = 0.037).ConclusionThe study highlights socio-demographic and clinical predictors of outcome, advancing our understanding of ADHD-addiction comorbidity. Findings warrant confirmation in prospective longitudinal research
L’acquisition de la théorie de l’esprit chez les enfants chinois : éclairages issus d'un outil de mesure peu verbal
No full textInternational audienceSince Wellman et al. (2006) first explored the developmental sequence of Theory of Mind (ToM) in Chinese children using the traditional ToM scale, research tools have been refined to minimize linguistic demands, which can impact children’s ToM development patterns (Burnel et al., 2018). The present study examined the new developmental sequence of ToM in Chinese preschoolers using an improved Low-Verbal ToM Scale With ExtEnded Trials (LV-ToM-SWEET). We measured six ToM abilities in 169 Chinese children aged 2.9–7.3 years (Mean age = 4.9 yrs, SD = 1.0 yrs, 73 boys), each with 3 trials instead of one. Results revealed a developmental sequence of Diverse Desires (DD) > Diverse Beliefs (DB) > Knowledge Access (KA) > Content False Belief (CFB) > Explicit False Belief (EFB) > Hidden Emotion (HE). This DB-before-KA pattern in Chinese children does not align with the collectivistic ToM pattern previously reported, instead it corresponds more closely to the model observed in individualistic cultures. Furthermore, the emergence of CFB and EFB as distinct steps within this sequence provides additional insights that refine and expand the traditional five-step ToM scale. The present study highlighted the role of improved methodologies, such as low-verbal tools, in uncovering nuanced ToM developmental patterns and provided new empirical insights into Chinese children’s ToM acquisition. The findings also highlight the need to assess how the rapid social transformations in China may contribute to shifts in children’s ToM acquisition.Depuis que Wellman et al. (2006) ont exploré pour la première fois la séquence développementale de la théorie de l’esprit (TE) chez les enfants chinois à l’aide de l’échelle traditionnelle de TE, les outils de recherche ont été affinés afin de réduire les exigences linguistiques, lesquelles peuvent influencer les trajectoires de développement de la TE chez les enfants (Burnel et al., 2018). La présente étude a examiné la séquence développementale de la TE chez des enfants chinois d’âge préscolaire en utilisant une version améliorée de l’échelle de TE à faible charge verbale avec plusieurs essais par compétence testée (Low-Verbal ToM Scale With Extended Trials ; LV-ToM-SWEET).Six compétences de TE ont été évaluées chez 169 enfants chinois âgés de 2,9 à 7,3 ans (âge moyen = 4,9 ans, ET = 1,0 ; 73 garçons), chacune mesurée à l’aide de trois essais au lieu d’un seul. Les résultats ont mis en évidence la séquence développementale suivante : Désirs Différents (DD) > Croyances Différentes (CD) > Accès à la Connaissance (AC) > Contenu Fausse Croyance (CFC) > Fausse Croyance Explicite (FCE) > Émotion Cachée (ÉC).Cette organisation, dans laquelle les Croyances Différentes précèdent l’Accès à la Connaissance chez les enfants chinois, ne correspond pas au profil collectiviste de la TE rapporté dans les travaux antérieurs, mais se rapproche davantage du modèle observé dans les cultures individualistes. En outre, les compétences en Contenu Fausse Croyance et Fausse Croyance Explicite comme étapes distinctes de cette séquence développementales apporte des éléments supplémentaires permettant d’affiner et d’enrichir l’échelle traditionnelle en cinq étapes de la TE.La présente étude met en lumière le rôle des méthodologies améliorées, telles que les outils à faible charge verbale, dans la mise au jour de profils développementaux plus nuancés de la TE et fournit de nouveaux éclairages empiriques sur l’acquisition de la TE chez les enfants chinois. Les résultats soulignent également la nécessité d’examiner dans quelle mesure les transformations sociales rapides en Chine peuvent contribuer à des changements dans l’acquisition de la TE chez les enfants
Identification of transdiagnostic phenomena among patients, the general population, relatives, and mental health professionals using topic modeling techniques
No full textInternational audienceIntroduction Recent research has highlighted the limitations of the categorical approach to mental disorders and has increasingly supported the development of a transdiagnostic perspective. This emerging approach focuses on common distal factors (circumstantial, biological, and social) and psychological processes that contribute to psychological suffering across a range of disorders, as well as on the resulting psychological symptoms. The present study aims to identify transdiagnostic distal factors, psychological processes, and symptoms by analyzing narratives through topic modeling—an unsupervised machine learning technique, specifically within Natural Language Processing (NLP). Topic modeling enables the automatic extraction of latent themes from unstructured text, making it possible to identify psychological patterns grounded in patients’ lived experiences. Methods We recruited four groups of participants: Patients diagnosed with a psychiatric disorder ( N = 445), Individuals from the general population ( N = 570), Relatives of patients with psychiatric disorders ( N = 354), and Mental health professionals ( N = 131). Participants answered open-ended questions exploring the causes of psychological suffering, their wishes for change, and their previous experiences with psychotherapy. Results We identified 258 topics, which were organized into 12 overarching themes. The most prominent topics concerned Emotional and Psychological Difficulties , Family and Social Relationships , and Therapeutic Processes . Each theme showed a comparable prevalence across the different diagnostic categories, supporting the transdiagnostic nature of these phenomena. Conclusion Topic modeling can be used effectively to identify transdiagnostic distal factors, psychological processes, and symptoms from diverse narratives. This approach tends to provide a novel means of supporting the relevance and validity of the transdiagnostic perspective
Weakening of hen egg vitelline membrane during egg storage at room temperature is associated with modifications of its mass, thickness and proteomic profile
No full textInternational audienceThe hen egg vitelline membrane is a protein layer surrounding the egg yolk. The integrity of this membrane is important for both the shell egg and the egg products industries; however, its physical properties are altered during prolonged storage, depending on storage temperature. This study aimed to identify the structural and molecular changes of the hen egg vitelline membrane during a 28-day storage at +4 °C and +20 °C using a combination of physicochemical, ultrastructural and proteomic approaches. Our results demonstrated that the degradation of the vitelline membrane during storage at +20 °C was associated with a significant loss of dry matter, a decrease in the thickness of the outer vitelline membrane layer, and alterations in its proteome. Indeed, the abundance of two main components of the outer layer, namely ovomucin and VMO1, decreased during storage at room temperature. VMO1 actually dissociates from the vitelline membrane during egg storage and accumulates in the egg white. Taken together, these results contribute to a better understanding of the mechanisms of alterations of the vitelline membrane during the storage of eggs at room temperature, and provide evidence that VMO1 is a major biomarker of the integrity of the vitelline membrane
Hétérodimérisation du récepteur aux oestrogènes couplés aux protéines G avec le récepteur de la LH biaise la signalisation dépendante des proteines G
No full textInternational audienceLH/choriogonadotropin (hCG) receptor (LHCGR) and the G protein-coupled estrogen receptor (GPER) are coexpressed in the ovary and support reproduction. The latter is involved in pathophysiological conditions and has been suggested as a potential therapeutic target. However, its role is still controversial, and several studies reported GPER to form heterocomplexes with other class A G protein-coupled receptors, modulating their signaling cascades. We evaluated if GPER interacts with LHCGR and impacts ligand-mediated pathways. In HEK293, LHCGR-GPER heteromers allosterically modulate LH/hCG-mediated signaling by preventing receptor coupling with Gq protein, leading to inhibition of phospholipase C pathway, and related transcriptional and mitogenic functions. This effect is prevented by mutant GPER unable to form heteromers with LHCGR. Interestingly, GPER expression has no effect on LH/hCG-induced Gs/cAMP/protein kinase A pathway activation, demonstrating selective inhibition of Gq pathway. These results were not recapitulated in cells displaying insufficient endogenous Gq protein expression levels, whereas they are recovered under exogenous Gq overexpression. Our data strengthen the concept that GPER may act as a modulator of other membrane G protein-coupled receptors, and a potential new target for treatment of tumors displaying Gq signalling