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WomenSOFar (ANR-21-CE03-0008) : un programme de recherche qui (re)pense les femmes et leurs environnements dans les sociétés passées
No full texthttps://bioarcheo.hypotheses.org/385
How do positive and negative emotions influence children’s and adolescents’ arithmetic performance?
No full textInternational audienceThis study is the first to investigate how negative and positive emotional states influence children's arithmetic performance and age-related differences therein. Children aged 8-14 (n = 149) were asked to verify true/false, one-digit addition problems (i.e., 8 + 2 = 10. True? False?) which were superimposed on emotionally negative, positive, or neutral pictures. The main results showed that (a) both positive and negative emotions impaired children's arithmetic performance, (b) deleterious effects of negative emotions were larger than those of positive emotions, (c) effects of emotions were modulated by the type of (true/false) problems, (d) effects of emotions on current trials were influenced by emotions on immediately preceding trials, and (e) effects of emotions as well as their trial-to-trial modulations changed with children's age. These findings have important implications for further our understanding of effects of emotions in children's arithmetic and how these effects change as children grow older. Age-related differences in effects of emotions in cognitive performance the effects of emotions first on cognitive performance and age-related changes in these effects and second in the specific domain of arithmetic. Age-related changes in effects of emotions on cognitive performanceEmotions can be defined as "episodic, relatively short-term biologically based pattern of perception, experience, physiology, action, and communication that occur in response to specifically physical and social challenges and opportunities" [5, p. 468]. These patterns of perception and experience are subjectively valenced as pleasant (positive) or unpleasant (negative). Numerous studies found that emotions influence participants' performance in a wide variety of cognitive domains, including attention, memory, reasoning, decision making, both in adults [1,2,] for overviews] and in children and adolescents [3]. In children and adolescents, like in adults, emotions can enhance, deteriorate, or have no effects on performance in different cognitive domains [3,6-11]. For example, Vasa et al. [11] found that 12-17-year-old adolescents recalled better positively and negatively valenced pictures than emotionally neutral pictures. This was also found in four-year-old children [10], in five to six-year-old children [12], and in eight-to 12-year-old children [8,13]. As another example, Howe et al. [6] found poorer recall performance in seven-and 11-year-old children for emotionally negative words relative to neutral words, and Leventon et al. [13] found no effects of emotions on recall performance in five-to eight-year-old children.Effects of emotions in both children and adults are usually accounted for by assuming that emotions capture participants' attention [8,14,15]. This may enhance crucial cognitive mechanisms used to accomplish the target cognitive task when emotions are task relevant (e.g., categorization of emotional and non-emotional words into "emotionally positive or negative words"). However, when emotions are task irrelevant (e.g., emotional images which are presented prior to the target task and are completely unrelated to the target cognitive task), they grab participants' exogeneous attention and interrupt/slow down cognitive mechanisms involved in the target task, and/or would generate a competition of resources between irrelevant emotional processing and relevant cognitive processing. As a result, participants are impaired in accomplishing the target task [16-18]. Besides attention capture, effects of emotions on cognitive performance can also be attributed to emotions influencing participants' motivation to engage in executing the target task [19-21]. As suggested by Pekrun's Control Value Theory [CVT, 4,19-21], effects of positive activating emotions (e.g., enjoyment) on participants' performance may be mediated by participants' engagement in learning. In contrast, negative emotions (e.g., boredom) may exert their deleterious effects via lowering participants' engagement in learning or while accomplishing cognitive tasks.</p
The Contributions of the Trilogy on the Legal Personality of the Animal
No full textVisual synthesis of the contributions of the scientific trilogy on the legal personality of animalsVisual synthesis of the contributions of the scientific trilogy on the legal personality of animal
Lactococcal phage–host profiling through binding studies between cell wall polysaccharide types and Skunavirus receptor-binding proteins
No full textInternational audienceDairy fermentations using mesophilic starter cultures rely on the activity of specific lactic acid bacteria (LAB) such as Lactococcus lactis and Lactococcus cremoris for the acidification of milk. This biotechnological process can be affected by bacteriophage infection of LAB starter strains, which may result in delayed or even failed fermentations. Most studied lactococcal phages commence infection with the binding of a tail-associated receptor-binding protein (RBP) to a host cell surface-exposed cell wall polysaccharide (CWPS). In the present study, phage prevalence and diversity in whey samples originating from fermentations performed in various European countries employing undefined mesophilic starter cultures were investigated using phageome analysis. The range of Skunavirus RBP genotypes present in the phageomes and associated RBP-CWPS binding abilities were evaluated, resulting in the refinement and expansion of the Skunavirus RBP grouping system and the identification of several heretofore unknown Skunavirus RBP (sub)groups. These findings substantially expand our knowledge on lactococcal Skunavirus RBP diversity and their binding specificity towards CWPS receptor structures, thereby improving the predictability of fermentation outcomes and robustness of starter culture rotations and blends
Tactile contribution extends beyond exteroception during spatially guided finger movements
No full textInternational audienceTraditionally, touch is associated with exteroception and is rarely considered a relevant sensory cue for controlling movements in space, unlike vision. We developed a technique to isolate and measure tactile involvement in controlling sliding finger movements over a surface. Young adults traced a 2D shape with their index finger under direct or mirror-reversed visual feedback to create a conflict between visual and somatosensory inputs. In this context, increased reliance on somatosensory input compromises movement accuracy. Based on the hypothesis that tactile cues contribute to guiding hand movements when in contact with a surface, we predicted poorer performance when the participants traced with their bare finger compared to when their tactile sensation was dampened by a smooth, rigid finger splint. The results supported this prediction. EEG source analyses revealed smaller current in the source-localized somatosensory cortex during sensory conflict when the finger directly touched the surface. This finding supports the hypothesis that, in response to mirror-reversed visual feedback, the central nervous system selectively gated task-irrelevant somatosensory inputs, thereby mitigating, though not entirely resolving, the visuo-somatosensory conflict. Together, our results emphasize touch’s involvement in movement control over a surface, challenging the notion that vision predominantly governs goal-directed hand or finger movements
Quelques empoignades avec les classiques (ou ce qu'il faudrait faire du 17e, selon divers auteurs contemporains)
No full textInternational audienc
Dynamics of Ionic and Cytotoxic Edema During Acute and Subacute Stages of Patients With Ischemic Stroke: Complementarity of <sup>23</sup>Na MRI and Diffusion MRI
No full textInternational audienceCerebral imaging is crucial in the diagnosis and treatment algorithm of acute stroke to determine salvageable brain tissue. While diffusion MRI is commonly used to define the ischemic core, it cannot reliably distinguish irreversibly damaged from salvageable tissue. We investigated the added value of 23 Na MRI to define irreversible necrotic tissue after a stroke. Fifteen patients with acute stroke involving medial cerebral artery occlusion were longitudinally explored with conventional and 23 Na MRI within 24 h, 70 h following stroke and at 3 months to characterize the necrotic area. Time-courses of sodium accumulations were observed within regions presenting with or spared by cytotoxic/ionic edema and converting or not to necrosis. Dynamics of sodium accumulations were very different across subjects. At the group level, time-courses of sodium signal in cytotoxic edema showed a non-linear increase with an upper asymptote of 59 ± 6%% relative to the contralateral hemisphere. Regions with a larger early increase in 23 Na signal (ionic edema) showed a non-linear accumulation during the first 70 h and were associated with subsequent necrosis at month 3. Some of the regions with no ionic edema during the first 70 h became necrotic at month 3, showing that pejorative pathophysiological processes could worsen after 70 h following attack. Final necrotic volume was well predicted by the cytotoxic volume (ADC decrease) during the first 24 h, and by the volume of ionic edema during the subacute period (25-70 h) following attack. The regions showing ionic edema showed a non-linear increase of 23 Na signal during the first 70 h, with larger sodium accumulations in regions converting to necrosis at month 3. It may be of interest to consider the role of ionic edema imaging in the 70 h after stroke and reperfusion, with a view to better understand stroke pathophysiology. Sodium MRI could add complementary information about the fate of cell necrosis within low ADC signal regions.</div
Euclid: Early Release Observations -- The surface brightness and colour profiles of the far outskirts of galaxies in the Perseus cluster
No full textInternational audienceThe Perseus field captured by Euclid as part of its Early Release Observations provides a unique opportunity to study cluster environment ranging from outskirts to dense regions. Leveraging unprecedented optical and near-infrared depths, we investigate the stellar structure of massive disc galaxies in this field. This study focuses on outer disc profiles, including simple exponential (Type I), down- (Type II) and up-bending break (Type III) profiles, and their associated colour gradients, to trace late assembly processes across various environments. Type II profiles, though relatively rare in high dense environments, appear stabilised by internal mechanisms like bars and resonances, even within dense cluster cores. Simulations suggest that in dense environments, Type II profiles tend to evolve into Type I profiles over time. Type III profiles often exhibit small colour gradients beyond the break, hinting at older stellar populations, potentially due to radial migration or accretion events. We analyse correlations between galaxy mass, morphology, and profile types. Mass distributions show weak trends of decreasing mass from the centre to the outskirts of the Perseus cluster. Type III profiles become more prevalent, while Type I profiles decrease in lower-mass galaxies with cluster centric distance. Type I profiles dominate in spiral galaxies, while Type III profiles are more common in S0 galaxies. Type II profiles are consistently observed across all morphological types. While the limited sample size restricts statistical power, our findings shed light on the mechanisms shaping galaxy profiles in cluster environments. Future work should extend observations to the cluster outskirts to enhance statistical significance. Additionally, 3D velocity maps are needed to achieve a non-projected view of galaxy positions, offering deeper insights into spatial distribution and dynamics
High-Gain Flexible Transparent Screen-Printed Quasi-Yagi Antenna for V-Band Applications
No full textInternational audienceIn this paper a flexible, V-band Quasi-Yagi Uda antenna is presented. The proposed antenna configuration is implemented on a 100 µm thick Zeonex transparent flexible substrate using a reliable screen-printing process. The antenna design is optimized to operate over 47.2 to 48.2 GHz frequency bands for emerging V-band applications. Measurements and simulations show a good agreement over the considered frequency band. The maximum measured peak gain is 10.4 dB at 47.2 GHz and the realized gain is higher than 8 dB over the entire frequency band of interest. A good input impedance matching is achieved in the 46.7 to 49.2 GHz frequency band. The surface occupied by the antenna is 15x20 mm. The antenna size does not exceed 15 mm by 20 mm. To further decrease the side lobe level in the E-plane, an optimization technique on the ground plane is also proposed as part of this work. The achieved performances demonstrate the feasibility of high-gain screen-printed end-fire antennas on highly transparent flexible at the millimeter-wave frequency range.</div
Description en vie réelle du phénomène d'hyper-progression chez des patients atteints de tumeurs solides traités par inhibiteurs de checkpoint immunitaire
No full textContexte : l’hyperprogression tumorale (HPD) est une complication rare mais potentiellement fatale des traitements par inhibiteurs de checkpoint immunitaire (ICI). Elle est définie par une accélération anormale de la croissance tumorale après initiation d’une immunothérapie. Son incidence réelle, ses facteurs de risque et son impact pronostique restent encore mal caractérisés en pratique courante. Objectif : identifier, en condition de vie réelle les cas d’HPD après traitement par ICI et décrire les profils cliniques, biologiques et la survie des patients hyperprogresseurs. Matériel et Méthode : HYPERPROG est une étude multicentrique rétrospective menée dans quatre centres français de lutte contre le cancer. L’outil ConSore, dédié à l'interrogation des dossiers médicaux électroniques, a permis d’identifier sur la période 2017-2023 les patients traités par ICI et qui présentaient une HPD. L’HPD était définie par l’association d’une augmentation de plus de 100 % du taux de croissance tumorale et d’une dégradation clinique. Résultats : sur 13 250 patients traités par ICI, 57 cas d'HPD ont été identifiés, soit une incidence globale de 0,43 %. Les cancers les plus concernés étaient les cancers pulmonaires (37 %), rénaux (14 %) et ORL (14 %). Le niveau d’expression de PD-L1 était équitablement réparti au sein de la cohorte, sans tendance en faveur d’un risque accru d’hyperprogression chez les patients à forte expression. L'hyperprogression survenait précocement, avec un délai médian de 31 jours après la première injection, et 75 % des cas dans les deux premiers mois. La survie globale médiane après HPD était de 4,0 mois, avec une survie à 12 mois de seulement 19 %. En analyse multivariée, un mauvais état général (PS ≥ 2) et une charge tumorale élevée (≥2 sites métastatiques) étaient associés à une survenue plus rapide de l’HPD, tandis que la présence d’une mutation driver semblait protectrice. Concernant la survie après HPD, la présence de métastases cérébrales et un état nutritionnel altéré (albumine <30 g/L) étaient associés à un pronostic péjoratif. Conclusion : l’HPD constitue un événement rare mais associé à un pronostic sombre. La survenue rapide du phénomène, dès les premières semaines d’immunothérapie, souligne l'importance d’une vigilance clinique et radiologique accrue, notamment chez les patients avec un haut volume tumoral et en situation de dénutrition. Une standardisation des critères de définition de l'HPD apparaît nécessaire pour améliorer son identification et orienter les pratiques cliniques futures