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A NEW ARMORED CROCODYLIFORM FROM THE UPPER CRETACEOUS OF CATALONIA (SPAIN): NEW INSIGHT INTO THE EVOLUTION OF THE EUSUCHIAN POSTCRANIAL AND DERMAL SKELETON
No full textpeer reviewedThe origin and early radiation of Crocodylia have shifted attention to the Upper Cretaceous of Europe, where numerous new taxa have recently been discovered. Particularly abundant are the remains associated with allodaposuchids, a controversial and recently established eusuchian clade whose postcranial record is rarely documented. Here, we describe a new allodaposuchid specimen from the Fontllonga-6 fossil locality (Àger Basin, NE Spain) in the Fontllonga Group (lower upper Maastrichtian). The specimen consists of cranial, postcranial, and dermal skeleton remains, making it the most complete crocodyliform from the Upper Cretaceous of Europe. It exhibits massive vertebrae and a large ribcage, while the numerous recovered osteoderms show diverse morphologies, providing insight into their position within the dermal skeleton. It presents peculiar teeth ornamentation only observed in Allodaposuchus palustris in the Ibero-Armorican domain. However, confident taxonomic assignment remains challenging due to the lack of other diagnostic traits. Including anatomical information provided by the specimen in phylogenetic analyses underscores the significance of postcranial characters in reconstructing the relationship within Eusuchia. This new finding fills a data gap in the postcranial anatomy of eusuchians and allodaposuchids, offering insights into the ecology of this successful clade from the Upper Cretaceous of Europe
The Place Where We Live. Outline of a theory of trauma through the ethnography of an Aboriginal support group (Sydney, Australia).
No full textProblematizing and modeling the sustainable neighborhood through an interdisciplinary inquiry at the time of the Anthropocene in high school: what interpretative space is shared between various social actors?
No full textpeer reviewedÀ l’ère de l’Anthropocène où l’humain est confronté à des changements globaux inédits, résultant de son activité industrielle et de son empreinte écologique (Delord, 2019), le pari sur les solutions technicistes pour sauver la planète est illusoire en raison de plusieurs limites du système Terre qui sont déjà outrepassées, parmi lesquelles le changement climatique, l’effondrement de la biodiversité terrestre et marine, l’altération des cycles biogéochimiques, l’appauvrissement de l’ozone stratosphérique, l’acidification des océans, l’utilisation globale de l’eau douce et des terres cultivables, la pollution chimique et la charge en aérosols atmosphériques (Rockström et al., 2009 ; Steffen et al., 2015). D’autant plus que le franchissement des deux premières limites est suffisant à lui seul pour « faire basculer l’ensemble du système Terre dans un fonctionnement nettement moins propice à la vie – et tout particulièrement à la vie humaine en société » (Redondo et al., 2022, p. 40).
Le tourbillon de la grande accélération de l’altération anthropique du système Terre (Rosa, 2017) est particulièrement alimenté par le développement incessant des technosciences (Albe, 2009 ; Hottois, 2005) comme l’agriculture intensive et les biotechnologies agricoles, les nanotechnologies, la gestion des déchets nucléaires, l’intelligence artificielle ou les technologies numériques. Si elles confèrent aux êtres humains une puissance inouïe sur le monde, les ressources puisées pour leur développement et les effets de leur utilisation sur l’environnement mettent en péril la vie sur Terre (Fabre, 2021). Dans le courant de pensée du post-modernisme, l’idéal moral de l’humain, hérité des Lumières, mène à une catastrophe d’un monde déshumanisé et dominé par la science et la technologie (Piron, 2003), trop exclusivement soumis aux contraintes du rapport coût-bénéfice (Lecourt, 2003). Dans les sociétés technologiquement avancées, il ne s’agit plus pour l’humain d’inscrire ces activités dans le paradigme de la croissance, mais plutôt dans celui de la décroissance en misant sur la sobriété dans l’exploitation des ressources, des modes de production et de consommation à toutes les échelles spatiales, du local au mondial. Pour ce faire, des initiatives alternatives dans toutes les sphères de l’activité humaine doivent être opérées sans plus tarder afin d’éviter un « futur barbare » (Bonneuil, 2022).
Les multiples changements globaux auxquels les humains sont confrontés constituent un vivier par excellence pour l’émergence des « problèmes complexes flous » (Toussaint et Lavergne, 2005), voire des problèmes pernicieux (Fabre, 2022). Ce type de problème interpelle ce que Legardez et Simonneaux (2006) appellent des questions socialement vives (QSV), soit des questions ouvertes qui suscitent des débats et dont la vivacité est tangible dans les savoirs de référence, la société et les savoirs scolaires. Ces questions mettent en jeu des « savoirs chauds » non stabilisés, chargés de valeurs éthiques, d’attentes comportementales et de compromis politiques (Lange et Victor, 2006). Soulevant des « controverses socioscientifiques » ou des « controverses sociotechniques » (Lascoumes, 2002 ; Simonneaux, 2011a), ces questions sont sujettes à des formes de « conflictualité » entre des acteur∙rices aux intérêts divergents et aux postions sociales contrastées, selon qu’ils∙elles privilégient des enjeux écologiques, sociaux, économiques ou politiques (Fabre, 2021 ; Hervé, 2019). Leur caractère multidimensionnel, l’incomplétude de leurs données et conditions ainsi que la pluralité de leurs solutions font en sorte de confronter les humains à plusieurs registres de l’incertitude (Nedelec et Molinatti, 2019, p. 65) :
L’incertitude épistémique (portant sur le statut des savoirs en jeu), l’incertitude des effets (quant aux conséquences des technosciences), l’incertitude des réponses possibles (quant aux décisions à prendre face à ces effets) et l’incertitude des acteurs prenant position dans l’arène sociale de la controverse (quant à leur place, leur responsabilité et leur légitimité dans cet espace).
Si l’incertitude peut contribuer à l’accroissement de l’anxiété, du stress ou d’un sentiment d’impuissance, elle peut être réduite par un engagement actif des acteurs dans des processus de résolution de problèmes conduisant à la recherche de solutions et à la construction de nouveaux savoirs sur le fonctionnement des phénomènes (Lancry, 2007). C’est dans cet esprit que se font les sciences citoyennes en intégrant activement les « citoyen∙nes ordinaires » dans des réflexions sur les controverses, prenant ainsi en compte de la vivacité des enjeux sociétaux dans les processus de production des savoirs (Simonneaux, 2019).
Dans la sphère éducative, le développement d’une culture scientifique et technique inclusive s’inscrit comme finalité de nombreux systèmes éducatifs qui promeuvent une éducation aux sciences plus citoyenne, en introduisant les controverses socioscientifiques ou sociotechniques à l’école (Albe, 2009 ; Girault et Molinatti, 2011 ; Urgelli, Hasni et Morin, 2022). L’enseignement des QSV y contribue en permettant aux élèves de comprendre et de participer à divers débats de la société portant sur des problèmes complexes (Albe et Simonneaux, 2002 ; Legardez, 2006 ; Simonneaux, 2019). C’est donc au niveau de la formation des élèves que se posent ces enjeux sociétaux, tant au niveau des connaissances que des compétences à leur faire acquérir. Une telle éducation citoyenne à l’ère de l’Anthropocène nécessite néanmoins de repenser, voire de reconfigurer les curricula pour mieux préparer les élèves à penser et agir dans ce monde problématique (Fabre, 2021 ; Lange et Kebaïli, 2019). Dès lors, quelles sont les caractéristiques et les modalités opératoires d’une telle formation citoyenne à l’ère de l’Anthropocène ?4. Quality education10. Reduced inequalities12. Responsible consumption and productio
Characterization of human papillomavirus virus-like particles using SEC and AF4 coupled with MALS
No full textpeer reviewe
Magnetic Field Conforming Formulations for Foil Windings
No full textpeer reviewedWe extend the foil winding homogenization method to magnetic field conforming formulations. We first propose a full magnetic field foil winding formulation by analogy with magnetic flux density conforming formulations. We then introduce the magnetic scalar potential in non-conducting regions to improve the efficiency of the model. This leads to a significant reduction in the number of degrees of freedom, particularly in 3-D applications. The proposed models are verified on two frequency-domain benchmark problems: a 2-D axisymmetric problem and a 3-D problem. They reproduce results obtained with magnetic flux density conforming formulations and with resolved conductor models that explicitly discretize all turns. Moreover, the models are applied in the transient simulation of a high-temperature superconducting coil. In all investigated configurations, the proposed models provide reliable results while considerably reducing the size of the numerical problem to be solved
Glucose metabolism in hyper-connected regions predicts neurodegeneration and speed of conversion in Alzheimer's disease.
No full textpeer reviewed[en] PURPOSE: Here, we combined a longitudinal design to assess whole-brain hyper- and hypo-connectivity in the different clinical phases of Alzheimer's disease (AD) with a multimodal approach to understand how such connectivity changes were related to glucose hypometabolism.
METHODS: We selected a longitudinal cohort of N = 66 subjects with clinical, cerebrospinal fluid and FDG-PET assessments, from Alzheimer's Disease Neuroimaging Initiative (ADNI) database. N = 31 AD individuals were assessed at three stages: mild cognitive impairment (AD-MCI, T0), early phase of dementia (mild-AD, T1) and dementia (AD-D, T2). We included N = 35 age/sex-matched healthy controls. We assessed longitudinal metabolic connectivity using Pearson's correlation, clustering analysis and graph theory metrics.
RESULTS: In the MCI-AD stages, hypo- and hyper-connectivity coexisted. Data-driven, longitudinal clustering analysis identified specific pathological clusters: a default mode network cluster, with prevalent hypo-connectivity and severe, persistent hypometabolism; a limbic cluster showing hyper-connectivity and steeper metabolic decline. Metabolism in hyper-connected limbic regions showed a mediation effect on worsening of AD-like parieto-temporal hypometabolism and predicted faster conversion to dementia.
CONCLUSION: Hypo- and hyper-connectivity, especially in early stages, may have different roles in AD neurodegenerative processes, with metabolism in hyper-connected regions acting as a mediator on the neurodegeneration of core regions of AD pathology
Response surface methodology optimization of alkaline extraction of polysaccharides from rapeseed meal: Structural characterization and antioxidant activities
No full textpeer reviewedRapeseed meal, a major by-product of oilseed processing, constitutes a rich and underutilized source of natural polysaccharides with promising functional potential. In this study, alkaline extraction was optimized using Box–Behnken design to isolate meal husk polysaccharide (HMP) and meal kernel polysaccharide (KMP) from rapeseed meal husk and kernel, respectively. Comprehensive physicochemical characterization revealed that both HMP and KMP were low-heterogeneity polysaccharides composed primarily of arabinose, galactose, glucose, xylose, and galacturonic acid. Despite originating from distinct anatomical parts, HMP and KMP exhibited comparable molecular weight distributions, Fourier-transform infrared (FTIR) spectra, and X-ray diffraction (XRD) patterns, indicative of amorphous or semi-crystalline structural features. Methylation and Nuclear magnetic resonance (NMR) analysis indicated that the arabinan featured (1 → 3)/(1 → 5) backbone organized around 2,3,5-trisubstituted residues serving as branching hubs; arabinan segments were grafted onto GalA at O-4, and the RG-I repeating unit [→2)-Rha-(1 → 4)-GalA-(1→] was present. Additionally, continuous (1 → 4)-xylan together with β-(1 → 4)-galactan and β-(1 → 4)-glucan bearing O-6 branches was identified, indicating that HMP and KMP were arabinan-dominated composite polysaccharides. Thermogravimetric analysis (TGA) demonstrated good thermal stability for both HMP and KMP. The slightly lower overall mass loss observed for KMP suggests greater thermal stability. Antioxidant activity assays, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and hydroxyl radical scavenging, confirmed the notable radical-scavenging capacities of both HMP and KMP, with KMP demonstrating relatively higher activity in the DPPH and ABTS systems. Scanning electron microscopy further revealed morphological differences, with HMP displaying a smoother and denser surface, whereas KMP exhibited a more porous and irregular microstructure. Additionally, both HMP and KMP effectively inhibited browning in fresh-cut apple models, underscoring their potential as natural antioxidant agents and edible coating materials. These findings provide theoretical and practical foundation for the valorization of rapeseed meal polysaccharides in the development of functional food and preservation technologies
Assessment of Outdoor Thermal Comfort in the Islamic Urban Fabric: A Case Study of the Casbah of Algiers
No full textGenetic Newborn Screening for Retinoblastoma: A Belgian Initiative Baby Detect.
No full textpeer reviewedBaby Detect Project, started in September 2022, aimed to create a newborn screening test using targeted next-generation sequencing for all early-onset, treatable, and serious conditions. The elaborated gene panel covers 405 genes, associated with 165 genetic conditions, and includes RB1, linked to retinoblastoma, the only oncological disease tested for. Germline RB1 mutations concern around 50% of all retinoblastoma cases and 100% of the most severe, bilateral cases. Ninety percent of them occur de novo, which delays the diagnosis by about a year with subsequent loss of vision and sometimes the eye itself. Detecting children with germline RB1 mutation at birth would greatly improve functional and anatomic outcomes, limiting invasive treatments and general anesthesias through early childhood. We discuss herein the novel approach of population screening, the rationale for newborn testing for RB1 mutations, the incidence of expected cases, the reliability of the test and its costs. The next step is to move to a nation-scale population; this initiative marks a landmark in retinoblastoma patients' care
Personalized prediction of SARS-CoV-2 vaccine-induced immunity after boost: a longitudinal analysis using joint modeling.
No full textpeer reviewedINTRODUCTION: The SARS-CoV-2 pandemic has revealed substantial inter-individual variability in immune responses, particularly following widespread primary vaccination and booster campaigns. These differences affect the durability of protective immunity and the need for additional booster doses. To optimize the management of current and future epidemics, there is a critical need for predictive tools that personalize immune monitoring and guide targeted booster strategies for vulnerable populations.
METHODS: In this study, we conducted a 15-month longitudinal analysis of a cohort of 1,000 individuals to identify key determinants of serological response following the first SARS-CoV-2 vaccine booster. We investigated how these factors influenced the risk of subsequent infection, and we developed statistical models to predict individual trajectories of anti-spike (S) IgG and neutralizing antibody (NAb) levels.
RESULTS-DISCUSSION: Our findings show that joint models (JMs), which integrate longitudinal antibody measurements with infection outcomes, significantly outperform traditional modeling approaches in predicting immune trajectories. This work underscores the potential of joint modeling to enable personalized immune surveillance, supporting strategies to sustain protective immunity in high-risk populations. In the future, this approach may be adapted for monitoring long-term immunity against other infectious diseases