Quand les mères portent leur enfant à gauche : qu’apprenons-nous de nos cousins les babouins ?

Chez l’humain, la majorité des mères (66 à 72 %) portent leur enfant du bras gauche. Ni la préférence manuelle, ni la culture, ni la position des battements du cœur ne semblent expliquer cette préférence. L’hypothèse faisant actuellement consensus implique la division du travail entre les deux hémisphères cérébraux, notamment la spécialisation de l’hémi- sphère droit dans le traitement des émotions. Porté à gauche, le bébé expose son visage dans le champ visuel gauche du parent. Ses expressio..

Dix ans d'histoire culturelle

L'association pour le développement de l'histoire culturelle (ADHC) est née, en 1999, du constat de la place croissante, en même temps que problématique, de l'histoire culturelle dans l'historiographie contemporaine. Revendiquée par les uns, dénoncée par les autres, cette place méritait l'institution d'un lieu de rencontres où tous ceux qui se reconnaissent dans cette qualification pourraient échanger sur le fond et sur la forme de leur travail. L'association a tenu son premier congrès en 2000. Au terme d'une décennie et plus d'activité, il était temps de tirer le bilan et, comme il se doit, de tracer de nouvelles perspectives. Cette anthologie des conférences et tables rondes organisées dans le cadre du congrès annuel de l'association propose un panorama unique en son genre des propositions avancées par l'histoire culturelle en France et, dans une moindre mesure, à l'étranger depuis dix ans. Regroupés en sections thématiques (définitions et frontières, objets, regards et transferts, débats), ces textes rédigés par d'éminents spécialistes venus de divers horizons (historiens, sociologues, philosophes, historiens de l'art ou de la littérature) donnent à voir à la fois la permanence de certains questionnements et leur renouvellement

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

On-board hydrogen production by hydrocarbon catalytic reforming

Le reformage d'isooctane dans des conditions fixées par la composition des gaz à l'échappement d'une voiture à essence peut être mis en oeuvre afin de produire de l'hydrogène embarqué. Des simulations thermodynamiques de reformage d'isooctane ont montré lIsooctane reforming under conditions which are set by exhaust gas can be performed on to generate hydrogen onboard. Isooctane reforming thermodynamic simulations have proven the possibility to produce a 10-15 % H2 effluent, according to internal combusti

Limb Preference in Animals: New Insights into the Evolution of Manual Laterality in Hominids

Until the 1990s, the notion of brain lateralization—the division of labor between the two hemispheres—and its more visible behavioral manifestation, handedness, remained fiercely defined as a human specific trait. Since then, many studies have evidenced lateralized functions in a wide range of species, including both vertebrates and invertebrates. In this review, we highlight the great contribution of comparative research to the understanding of human handedness’ evolutionary and developmental pathways, by distinguishing animal forelimb asymmetries for functionally different actions—i.e., potentially depending on different hemispheric specializations. Firstly, lateralization for the manipulation of inanimate objects has been associated with genetic and ontogenetic factors, with specific brain regions’ activity, and with morphological limb specializations. These could have emerged under selective pressures notably related to the animal locomotion and social styles. Secondly, lateralization for actions directed to living targets (to self or conspecifics) seems to be in relationship with the brain lateralization for emotion processing. Thirdly, findings on primates’ hand preferences for communicative gestures accounts for a link between gestural laterality and a left-hemispheric specialization for intentional communication and language. Throughout this review, we highlight the value of functional neuroimaging and developmental approaches to shed light on the mechanisms underlying human handedness

Maternal cradling bias in baboons: The first environmental factor affecting early infant handedness development?

International audienceThe most emblematic behavioral manifestation of human brain asymmetries is handedness.While the precise mechanisms behind the development of handedness are still widelydebated, empirical evidences highlight that besides genetic factors, environmental factorsmay play a crucial role. As one of these factors, maternal cradling behavior may play a key rolein the emergence of early handedness in the offspring. In the present study we followed 41Papio anubis infants living in social groups with their mother for which direction (e.g., left- orright-arm) and degree of maternal cradling-side bias were available from a previous publishedstudy. We assessed hand preferences for an unimanual grasping task at 3 developmentalstages: (A) 0-4, (B) 4-6 and (C) 9-10 months of age. We found that individual hand preferencesfor grasping exist as soon as the first months of age, with a population-level left-handednesspredominance, being stable until 6 months; to wit the period during which juveniles are mainlycarried by their mothers. More importantly, this early postnatal handedness is positively correlated with maternal cradling lateralization. Interestingly, hand preferences assessed laterin the development, once juveniles are no longer carried (i.e., from 9 to 10 months of age),are less dependent from the maternal cradling bias and less consistent with the earlierdevelopmental stages, especially in infants initially cradled on the right maternal side. Ourfindings suggest that the ontogenetic dynamics of the infant’s hand preference and its changesmight ultimately rely on the degree of infant dependence from the mother acrossdevelopment

Human-like maternal left-cradling bias in monkeys is altered by social pressure

International audienceAbout 66-72% of human mothers cradle their infants on their left side. Given that left-cradling exposes the baby's face to the mother's left visual field (i.e., mainly projected to her right hemisphere) and is altered by emotional states such as stress, maternal left-cradling was interpreted as reflecting right-hemispheric dominance for emotional processing. Whether this phenomenon is unique to human evolution is still in debate. In the present study we followed 44 olive baboon (Papio anubis) mothers and their infants in different social groups. We found that a maternal cradling bias exists and is predominantly towards the left in a similar proportion as in humans, but shifts toward a right bias in mothers living in high density groups. The sensitivity of left-cradling to social pressure highlights its potential links with the mother's stress as reported in humans. Our finding clearly illustrates the phylogenetic continuity between humans and Old-World monkeys concerning this lateralization and its potential links with hemispheric specialization for emotions, inherited from a common ancestor 25-35 million years ago

Quand les mères portent leur enfant à gauche : qu’apprenons-nous de nos cousins les babouins ?

International audienc

Maternal cradling bias in baboons: the first environmental factor affecting early infant handedness development?

International audienc

Maternal cradling bias drives early handedness in infant monkeys: A longitudinal study of grasping lateralization in baboons

The most emblematic behavioral manifestation of human brain asymmetries is handedness. While the precise mechanisms behind the development of handedness are still widely debated, empirical evidences highlight that besides genetic factors, environmental factors may play a crucial role. As one of these factors, maternal cradling behavior may play a key role in the emergence of early handedness in the offspring. In the present study we followed 41 olive baboon ( Papio anubis ) infants living in different social groups with their mother for which direction (e.g., left- or right-arm) and degree of maternal cradling-side bias were available from our previous published study. We assessed hand preferences for an unimanual grasping task at 3 developmental stages: (1) 0-4, (2) 4-6 and (3) 9-10 months of age. We found that individual hand preferences for grasping exist as soon as the first months of age, with a population-level left-handedness predominance, being stable until 6 months; to wit the period during which juveniles are mainly carried by their mothers. More importantly, this early postnatal handedness is positively correlated with maternal cradling lateralization. Interestingly, hand preferences assessed later in the development, once juveniles are no longer carried (i.e., from 9 to 10 months of age), are less consistent with the earlier developmental stages and no longer dependent from the maternal cradling bias. Our findings suggest that the ontogenetic dynamics of the infant’s hand preference and its changes might ultimately rely on the degree of infant dependence from the mother across development