Carbon nanotubes prepared in situ in a cellular ceramic by the gelcasting-foam method

The synthesis of carbon nanotubes from an oxide solid solution foam is reported for the first time. A foam of Mg0.9Co0.1Al2O4 solid solution is prepared by the gelcasting-foam method using notably mono- and di-functional acrylate monomers. Using a surfactant in the alkylpolyglucoside family allows to prevent structure changes in the foam before the onset of polymerisation. The wet ceramic foam is dried in air, producing a foam with an open porosity. Total porosity is equal to about 98% and the diameter of the pores is in the range 25–300 mm, about 90% being smaller than 200 mm. The Mg0.9Co0.1Al2O4 foam is reduced in H2–CH4 atmosphere, giving rise to a CNTs–Co MgAl2O4 composite foam. Using the foam instead of the corresponding powder allows a fourfold increase in the production of carbon nanotubes, more than 95% of which have only 1 (70%) or 2 walls

Poésie et enseignement de la courtoisie dans le duché d’Aquitaine aux xiie et xiiie siècles : examen de quatre ensenhamens

Le duché d’Aquitaine a vu naître l’art lyrique occitan aux xiie et xiiie siècles. Cette poésie comporte un volet didactique qui a contribué à son succès, grâce au genre des ensenhamens. Dans ce cadre s’ébaucha un modèle laïc de comportement en contrepoint des efforts de l’Église catholique pour domestiquer l’aristocratie. Le but de notre communication est donc d’explorer pourquoi et comment cette pédagogie de la courtoisie, observée au travers des quatre ensenhamens rédigés à cette époque et dans cet espace, est apparue. Il s’agit tout d’abord de remettre en perspective ses contenus. Il faut ensuite en préciser les moyens. Enfin, la question des acteurs – émetteurs et récepteurs – doit être posée. Cette étude permet au final de percevoir les déterminants des attitudes de chaque membre des cours d’Aquitaine aux xiie et xiiie siècles, en mettant notamment l’accent sur les effets de la distance sociale entre les partenaires des échanges poétiques

Écriture et transmission des savoirs de l’Antiquité à nos jours

Pendant longtemps, la transmission des savoirs s’est faite directement, du maître à l’élève, de l’artisan à l’apprenti, par un enseignement oral que venait compléter la démonstration des gestes de la pratique. L’apparition de l’écriture, et plus encore la diffusion de la literacy ont fait que des méthodes de transmission indirectes ont pu se faire jour et que l’acquisition d’un savoir, quel qu’il soit, a pu se faire sans contact immédiat avec le détenteur de ce savoir, mais par le truchement d’un livre ou d’une autre forme d’écrit. Il s’est ensuivi une capacité de diffusion des savoirs quasiment illimitée, des plus techniques et spécialisés aux plus abstraits et généralistes. C’est cette explosion de la transmission des savoirs que les vingt auteurs des contributions ici réunies ont cherché à explorer en mettant en lumière différentes facettes, à travers une série d’exemples, allant de l’Antiquité à l’époque contemporaine. Le Congrès national des sociétés historiques et scientifiques rassemble chaque année universitaires, membres de sociétés savantes et jeunes chercheurs. Ce recueil est issu de travaux présentés lors du 143e Congrès sur le thème « La transmission des savoirs »

Vaccine breakthrough hypoxemic COVID-19 pneumonia in patients with auto-Abs neutralizing type I IFNs

Life-threatening `breakthrough' cases of critical COVID-19 are attributed to poor or waning antibody response to the SARS- CoV-2 vaccine in individuals already at risk. Pre-existing autoantibodies (auto-Abs) neutralizing type I IFNs underlie at least 15% of critical COVID-19 pneumonia cases in unvaccinated individuals; however, their contribution to hypoxemic breakthrough cases in vaccinated people remains unknown. Here, we studied a cohort of 48 individuals ( age 20-86 years) who received 2 doses of an mRNA vaccine and developed a breakthrough infection with hypoxemic COVID-19 pneumonia 2 weeks to 4 months later. Antibody levels to the vaccine, neutralization of the virus, and auto- Abs to type I IFNs were measured in the plasma. Forty-two individuals had no known deficiency of B cell immunity and a normal antibody response to the vaccine. Among them, ten (24%) had auto-Abs neutralizing type I IFNs (aged 43-86 years). Eight of these ten patients had auto-Abs neutralizing both IFN-a2 and IFN-., while two neutralized IFN-omega only. No patient neutralized IFN-ss. Seven neutralized 10 ng/mL of type I IFNs, and three 100 pg/mL only. Seven patients neutralized SARS-CoV-2 D614G and the Delta variant (B.1.617.2) efficiently, while one patient neutralized Delta slightly less efficiently. Two of the three patients neutralizing only 100 pg/mL of type I IFNs neutralized both D61G and Delta less efficiently. Despite two mRNA vaccine inoculations and the presence of circulating antibodies capable of neutralizing SARS-CoV-2, auto-Abs neutralizing type I IFNs may underlie a significant proportion of hypoxemic COVID-19 pneumonia cases, highlighting the importance of this particularly vulnerable population

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

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

Troubadours and society in 12th century Aquitaine (1071-1199)

L'objectif initial de notre travail était d'enquêter sur la présence des troubadours aquitains du XIIe siècle dans les sociétés qu'ils fréquentèrent. L'étude montre qu'ils ne formaient pas un groupe social au sens contemporain du terme. D'une part, ils venaient de milieux très différents. D'autre part, leur positionnement au sein des cours a évolué au cours du temps. Jusqu'aux années 1130, les troubadours se faisaient les porte-paroles de l'ensemble des membres de cours aux contours bien définis, dans un contexte politique marqué par des révoltes récurrentes. L'espace aquitain traversait alors une période de recomposition territoriale qui aboutit finalement à un changement de capitale, de Poitiers vers Bordeaux. Le troubadour Marcabru changea radicalement de perspective en se plaçant délibérément en dehors de l'espace courtisan, dans un rôle se rapprochant du prédicateur laïc. Il fut imité par un certain nombre de troubadours jusque dans les années 1150. Après cette date, une nouvelle génération de poètes abandonna cette posture. Ils transcrivaient dans leurs oeuvres les expériences d'hommes et de femmes confrontés au renforcement du contrôle étatique sur la noblesse. Par-là, ces troubadours élaborèrent un modèle de comportement qui inspira les aristocrates de Catalogne, de Languedoc, de Provence et du nord de l'Italie, où l'héritage des troubadours finit par être conservé. La rédaction ultérieure des chansonniers provençaux, dont aucun ne fut écrit en Aquitaine, correspondit en effet à une démarche patrimoniale et mémorielle et au besoin de disposer de modèles de comportement. Cela créa l'illusion, par-delà les siècles, qu'une véritable communauté avait existé parmi les troubadours aquitains du XIIe siècle, là où il serait plus judicieux d'évoquer une communauté créée a posteriori par un corpus de textes collectés tardivement.This work aims to investigate the behavior of the Aquitanian troubadours of the 12th century. It is impossible to see them as a social group, for two main reasons. First, their social and familial background were too different from one another. Second, the way they performed their poetry changed between the beginning and the end of the 12th century. Until the 1130's, they acted as if they were the spokesman of their friends and allies. In those years, the dukes of Aquitaine faced several rebellion movements, which gradually led them to move their capital city from Poitiers to Bordeaux. Shortly after the year 1130, the troubadour Marcabru adopted a new and radically different approach, speaking to cortesans as if he were a lay preacher. But after his death, a new generation of poets abandoned this posture for another one. They sang about the everyday experience of cortesans in a time of reinforcement of the central states in western Europe. They created new models of behavior that inspired aristocrats from Catalonia, Languedoc, Provence and Northern Italy. As rich gentlemen of these regions sponsored the writing of selected anthologies, they took advantage of legacy of the Aquitanian troubadours of the 12th century. Later, these compilations gave birth to the idea that the troubadours had formed a real community, but it would be better to speak of an illusory community created by the act of compiling itself

Machine-Learning Exploration of Exposure-Effect Relationships of Cisplatin in Head and Neck Cancer Patients

International audienceBackground: Cisplatin is a pivotal drug in the treatment of head and neck cancer, and personalized dosage should help the preservation of an optimal toxicity–efficacy ratio. Methods: We analyzed the exposure-effect relationships of 80 adult patients with head and neck cancers and treated with standard Cisplatin-based regimen administered as three-hour infusion. Individual pharmacokinetics (PK) parameters of Cisplatin were identified using a Bayesian approach. Nephrotoxicity and ototoxicity were considered as typical Cisplatin-related toxicities according to Common Terminology Criteria for Adverse Events (CTCAE) standards. Efficacy was evaluated based upon Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Up to nine different machine-learning algorithms were tested to decipher the exposure-effect relationships with Cisplatin. Results: The generalized linear model was the best algorithm with an accuracy of 0.71, a recall of 0.55 and a precision of 0.75. Among the various metrics for exposure (i.e., maximal concentration (Cmax), area-under-the-curve (AUC), trough levels), Cmax, comprising a range between 2.4 and 4.1 µg/mL, was the best one to be considered. When comparing a consequent, model-informed dosage with the standard dosage in 20 new patients, our strategy would have led to a reduced dosage in patients who would eventually prove to have severe toxicities while increasing dosage in patients with progressive disease. Conclusion: Determining a target Cmax could pave the way for PK-guided precision dosage with Cisplatin given as three-hour infusion

High NV density in a pink CVD diamond grown with N2O addition

International audienc

From a drug repositioning to a structure-based drug design approach to tackle acute lymphoblastic leukemia

Abstract Cancer cells utilize the main de novo pathway and the alternative salvage pathway for deoxyribonucleotide biosynthesis to achieve adequate nucleotide pools. Deoxycytidine kinase is the rate-limiting enzyme of the salvage pathway and it has recently emerged as a target for anti-proliferative therapies for cancers where it is essential. Here, we present the development of a potent inhibitor applying an iterative multidisciplinary approach, which relies on computational design coupled with experimental evaluations. This strategy allows an acceleration of the hit-to-lead process by gradually implementing key chemical modifications to increase affinity and activity. Our lead compound, OR0642, is more than 1000 times more potent than its initial parent compound, masitinib, previously identified from a drug repositioning approach. OR0642 in combination with a physiological inhibitor of the de novo pathway doubled the survival rate in a human T-cell acute lymphoblastic leukemia patient-derived xenograft mouse model, demonstrating the proof-of-concept of this drug design strategy