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Effects of selection for divergent levels of social motivation on behavioral synchronization in Japanese quail (Coturnix japonica)
No full textInternational audienceOur study aims to deepen the understanding of how intra-group, inter-individual differences in social motivation influences group organization and, more specifically, behavioral synchronization. Behavioral synchronization is defined as individuals displaying the same behavior, at the same time and at the same place. It is known to provide substantial adaptative benefits, such as enhanced social cohesion. Here, we investigated how genetic selection for social motivation in Japanese quail (Coturnix japonica) impacts their behavioral repertoire and their behavioral synchronization, by comparing 10 trios (groups of three) constituted of individuals selected for high social motivation (S+) and 10 trios constituted of individuals selected for low social motivation (S-) in a synchronization test. For this test, trios were placed for 24 consecutive hours in an arena filled with wood shavings and providing ad libitum access to food and water. Birds’ behaviors were recorded and analyzed during four one-hour time windows (hour 1: 8:30–9:30 am, hour 2: 11:00–12:00 am, hour 3: 1:30–2:30 pm and hour 4: 4:00–5:00 pm). Results revealed that S- quail displayed more locomotion behaviors, while S+ quail exhibited more inactivity behaviors and particularly “sit relaxed” behaviors. Also, S+ individuals had a longer total synchronization duration than S- individuals, particularly in “sit relaxed” behaviors. Specifically, S+ quail performed more synchronized “sit relaxed” behaviors, spent more time in this state and remained synchronized longer during “sit relaxed” bouts compared to S- quail. This was further supported by a higher Kappa coefficient for this specific behavior, indicating less random synchronization in the S+ group. The “sit relaxed” behavior was also the only one to reduce inter-individual distances during synchronization bouts, suggesting that the birds voluntarily chose to group together. Overall, these findings suggest that individuals with higher social motivation are more likely to engage in synchronized behaviors, particularly during resting behaviors, which may promote close proximity and strengthen social bonds. Such synchronization may foster social cohesion and lead to more stable and harmonious group dynamics. Further studies will be necessary to better elucidate these effects and confirm these different hypotheses. This research offers valuable insights into the important role of individuals’ social motivation in shaping collective behaviors and its potential to encourage behaviors that favor positive animal welfare
Design, synthesis and evaluation of the first 2-alkynyl(aza)indole F probe targeting α-synuclein aggregates
No full textInternational audienceBackground/Objectives: The role of α-synuclein (α-syn) in the pathogenesis of Parkinson's disease (PD) or neurodegenerative diseases such as Lewy body dementia (LBD) and multiple system atrophy (MSA) is commonly accepted. Through different physiological dysfunctions, abnormal forms of α-syn are generated. These abnormal aggregates accumulate and alter pre-and postsynaptic transmission, in particular that of dopamine. Thus, the development of a diagnostic biomarker of synucleinopathies remains crucial and challenging. The development of an α-syn positron emission tomography (PET) radiopharmaceutical may be suitable to early diagnose and stratify patients, follow up disease progression, and evaluate future therapies. Methods: To develop a selective α-syn PET tracer, we synthesized an original series based on alkynyl(aza)indoles. Fifteen final ligands were synthesized bearing indoles or azaindoles from one side of the alkyne and a substituted phenyl ring for the opposite side of the alkyne. The final ligands were tested to determine Ki and/or Kd toward α-syn, tau, and Aβ. Results: The SAR showed that the indole series exhibited moderate to low affinity for α-syn and, moreover, lower Ki toward Aβ and tau (i.e., compound 39, Ki (αsyn) 21.7 nM, Ki (Aβ) 64.4 nM, Ki (Tau) 27.6 nM), highlighting the low potency of these series to afford an α-syn tracer. The introduction of a nitrogen on the different positions of the phenyl to obtain the corresponding azaindoles resulted for most of the compounds in better affinity for α-syn and selectivity towards Aβ compared to the indole analogs (i.e., compound 43, Ki (αsyn) 4.7 nM, Ki (Aβ) 24.4 nM, and Ki (Tau) 4.61 nM). A fluorinated azaindole derivative was prepared with a view to obtaining a 18 F tracer and exhibited the highest affinity for α-syn but without selectivity against tau and Aβ. The radiosynthesis of [ 18 F]45 was performed in a two-step procedure starting from the tosylated and protected precursor. [ 18 F]45 was obtained in 85 ± 5 min with a radiochemical yield of 32 ± 3%. Molar activity, determined from a calibration with stable 45, was around 130 GBq/µmole. The dynamic PET imaging showed that [ 18 F]45 was able to cross the blood-brain barrier, but non-specific uptake was observed, confirming the in vitro results. Conclusions: Although promising nanomolar affinity for the target, the new tracer showed mainly non-specific in vivo uptake in the rat brain, indicating that further pharmacomodulations on the azaindole series are required
Prevention and management of syphilis in pregnant and perinatal women
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A comparative analysis of metamodels for 0D cardiovascular models, and pipeline for sensitivity analysis, parameter estimation, and uncertainty quantification
No full textInternational audienceZero-dimensional (0D) cardiovascular models are reduced-order models aimed at studying the global dynamics of the whole circulation system or transport within it. They are employed to obtain estimates of important biomarkers for surgery planning and assessment applications (such as pressures, volumes, flow rates, and concentrations in the circulation) and can provide boundary conditions for high-fidelity three-dimensional models. Despite their low computational cost, tasks such as parameter estimation or uncertainty quantification require a large number of model evaluations, which is still a computationally expensive task. This motivates the building of metamodels in an offline stage, which can be evaluated significantly faster than 0D models. In this work, a pipeline going from 0D cardiovascular models to the building of metamodels and showcasing their use for tasks such as sensitivity analysis, parameter estimation, or uncertainty quantification is proposed. Three different strategies are assessed to build metamodels for 0D cardiovascular models, namely Neural Networks, Polynomial Chaos Expansion, and Gaussian Processes. The metamodels are assessed for three different 0D models. The first is a lumped model aimed at predicting the pressure in the portal vein after surgery. Due to the strong interaction between local liver hemodynamics and global circulation, the full circulation is modeled. The second one is simulating the whole-body circulation under the conditions of pulmonary arterial hypertension before and after shunt insertion. The final model is aimed at assessing the blood perfusion of an organ after a revascularization surgery. The transport of a contrast agent is modeled on top of a simplified 0D hemodynamics model. This model is chosen due to the different nature of the output which is a signal (concentration of the contrast agent over time), which requires a different treatment from the metamodeling point of view. The metamodels are trained and tested on synthetic data generated from the 0D models. It was found that neural networks offer the most convenient way of building metamodels in terms of the quality of the results, computational time, and practical ease of performing parameter estimation, sensitivity analysis, or uncertainty quantification tasks. Finally, we demonstrate a full pipeline of sensitivity analysis, inverse problem and (patient-specific) UQ, with a neural network as emulator
Introduction. Local cases and global trends in recovering recyclable waste
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Effets différenciés des organisateurs graphiques sur la mémorisation d’élèves de cycle 2 et 3
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Vies sociales et politiques des rebuts: Mondes de la récupération, injustices environnementales et mobilisations citoyennes
No full textInternational audienceCe texte introduit, présente et met en perspective les contributions de la 37ème livraison des Cahiers d’EMAM, consacrée aux rebuts dans l’espace méditerranéen. Ce numéro paraît à l’heure où la thématique connaît un net dynamisme académique, issu notamment de travaux de doctorant·es et jeunes chercheur·euses qui en renouvellent les entrées, approches et contextes d’analyses. Cette introduction appelle à considérer les rebuts comme des objets sociaux et politiques, permettant de renouveler l’étude des pratiques socio-économiques et inégalités urbaines et environnementales en Méditerranée. En s’appuyant sur les enquêtes de terrain menées dans plusieurs contextes urbains par les auteur·es du numéro, nous mettons en lumière le fait que les mondes de la récupération constituent des économies populaires structurées, dotées de savoir-faire, de normes et de formes de politisation spécifiques. Nous montrons, en outre, les tensions produites par les politiques publiques de gestion et de valorisation des déchets, qui tendent à invisibiliser, voire à marginaliser, certains acteurs. Enfin, ce texte esquisse un cadre analytique pour penser les rebuts comme poste d’observation privilégié des rapports de pouvoir, des modes de gouvernance urbaine et des mobilisations citoyennes contemporaines
Définitions et méthodes d’évaluation des états mentaux des animaux
No full textInternational audienceD’abord restreint à l’absence d’émotion négative et au respect des besoins des animaux, le bien-être de l’animal a été défini comme résultant d’un état mental positif. Ce changement de paradigme a placé les états mentaux au cœur des recherches sur le bien-être animal. Or, il est encore difficile de les définir et de les évaluer, deux objectifs que nous visons dans cet article. Après avoir rappelé quelques éléments historiques et scientifiques qui nous paraissent fondamentaux, nous proposons de définir les états mentaux comme l’ensemble des processus impliqués dans les états affectifs, les cognitions sociale, physique et incarnée. Cette définition est cohérente avec la définition et les méthodes d’évaluation du bien-être de l’animal, ces dernières ayant d’abord été focalisées sur les états affectifs comme les émotions. Nous rappellerons plusieurs approches expérimentales pour comprendre les états affectifs des animaux de ferme et quelques approches mises en œuvre pour les évaluer en élevage. Pour accéder aux autres états mentaux tels que les différentes formes de cognition, nous proposons d’explorer les démarches mises en œuvre pour diagnostiquer et prendre en charge la santé mentale des animaux et des humains. En particulier, nous nous intéressons au projet Research Domain of Criteria (RDoC) qui offre un cadre pertinent pour étudier et évaluer les états mentaux des animaux. Nous discuterons son intérêt et évoquerons, en perspective, la mise en œuvre d’un tel projet pour explorer les substrats biologiques des états mentaux, identifier de nouveaux indicateurs de bien-être, et engager une approche intégrant à la fois bien-être et santé