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Viral and immune dynamics of HPV genital infections in young women
No full textHuman papillomavirus (HPV) infections drive one in twenty new cancer cases. Despite the potential for improving treatment, screening, and vaccination strategies, little is known as to why most HPV infections clear spontaneously within two years. To untangle the dynamics of these non-persisting infections, we performed a combined quantitative analysis of virological, immunological, and clinical data from an original longitudinal cohort of 189 women with high temporal resolution. We find that HPV viral load reaches a plateau within two months, and clears within a median time of 14 months. Furthermore, we identify immune correlates associated with infection clearance, especially TCR-gamma-delta cells. Our results open new perspectives for understanding the frontier between acute and chronic infections and for controlling HPVassociated diseases
Oggi sento la mia immobilità come un tormento: Forme dell'adattamento
No full texthttps://www.padovauniversitypress.it/it/publications/9788869384141International audienc
La défense du Filioque chez Georges Métochitès (v. 1250-1328) : redécouvrir un promoteur byzantin de l’union avec l’Église de Rome
No full textInternational audienc
Zombies chinois
No full textNational audienceDans quelle mesure peut-on parler de zombies chinois ? Si aucun être de la tradition chinoise ne ressemble trait pour trait au zombi haïtien, on notera que le thème de la réduction des morts en esclavage est présent à travers des figures comme celles du chang 倀, fantôme obligé de procurer de nouvelles proies au tigre qui l’a dévoré, ou des victimes du poison gu 蠱, réduits à servir, ante mortem comme post mortem, le sorcier qui le leur a administré. Les « cadavres raidis », jiangshi 僵屍, sont quant à eux, non des fantômes, lesquels conservent la personnalité qu’ils avaient de leur vivant, mais des cadavres sans âmes, se ranimant pour s’en prendre aux vivants dans le but de s’approprier leurs souffles vitaux. Ce sont ces derniers personnages qui figurent en très bonne place depuis les années 1970 dans le cinéma fantastique de Hong-Kong, dans un registre rappelant le film de zombis hollywoodien tout en s’inspirant de la tradition chinoise
Protonated acetylene in the z=0.89 molecular absorber toward PKS1830-211
No full textAccepted for publication in A&AInternational audienceWe report the first interstellar identification of protonated acetylene, C2H3+, a fundamental hydrocarbon, in the z=0.89 molecular absorber toward the gravitationally lensed quasar PKS1830-211. The molecular species is identified from clear absorption features corresponding to the 2_12-1_01 (rest frequency 494.034 GHz) and 1_11-0_00 (431.316 GHz) ground-state transitions of ortho and para forms of C2H3+, respectively, in ALMA spectra toward the southwestern image of PKS1830-211, where numerous molecules, including other hydrocarbons, have already been detected. From the simple assumption of local thermodynamic equilibrium (LTE) with cosmic microwave background photons and an ortho-to-para ratio of three, we estimate a total C2H3+ column density of 2 x 10^12 cm^-2 and an abundance of 10^-10 compared to H_2. However, formation pumping could affect the population of metastable states, yielding a C2H3+ column density higher than the LTE value by a factor of a few. We explore possible routes to the formation of C2H3+, mainly connected to acetylene and methane, and find that the methane route is more likely in PDR environment. As one of the initial hydrocarbon building blocks, C2H3+ is thought to play an important role in astrochemistry, in particular in the formation of more complex organic molecules
YOLO-CIANNA: Galaxy detection with deep learning in radio data
No full textInternational audienceContext . The upcoming Square Kilometer Array (SKA) will set a new standard regarding data volume generated by an astronomical instrument, which is likely to challenge widely adopted data-analysis tools that scale inadequately with the data size. Aims . The aim of this study is to develop a new source detection and characterization method for massive radio astronomical datasets based on modern deep-learning object detection techniques. For this, we seek to identify the specific strengths and weaknesses of this type of approach when applied to astronomical data. Methods . We introduce YOLO-CIANNA, a highly customized deep-learning object detector designed specifically for astronomical datasets. In this paper, we present the method and describe all the elements introduced to address the specific challenges of radio astronomical images. We then demonstrate the capabilities of this method by applying it to simulated 2D continuum images from the SKA observatory Science Data Challenge 1 (SDC1) dataset. Results . Using the SDC1 metric, we improve the challenge-winning score by +139% and the score of the only other post-challenge participation by +61%. Our catalog has a detection purity of 94% while detecting 40–60% more sources than previous top-score results, and exhibits strong characterization accuracy. The trained model can also be forced to reach 99% purity in post-process and still detect 10–30% more sources than the other top-score methods. It is also computationally efficient, with a peak prediction speed of 500 images of 512×512 pixels per second on a single GPU. Conclusions . YOLO-CIANNA achieves state-of-the-art detection and characterization results on the simulated SDC1 dataset and is expected to transfer well to observational data from SKA precursors
Scattering Spectra Models for Physics
No full textInternational audiencePhysicists routinely need probabilistic models for a number of tasks such as parameter inference or the generation of new realizations of a field. Establishing such models for highly non-Gaussian fields is a challenge, especially when the number of samples is limited. In this paper, we introduce scattering spectra models for stationary fields and we show that they provide accurate and robust statistical descriptions of a wide range of fields encountered in physics. These models are based on covariances of scattering coefficients, i.e. wavelet decomposition of a field coupled with a point-wise modulus. After introducing useful dimension reductions taking advantage of the regularity of a field under rotation and scaling, we validate these models on various multi-scale physical fields and demonstrate that they reproduce standard statistics, including spatial moments up to 4th order. These scattering spectra provide us with a low-dimensional structured representation that captures key properties encountered in a wide range of physical fields. These generic models can be used for data exploration, classification, parameter inference, symmetry detection, and component separation
YOLO-CIANNA: Galaxy detection with deep learning in radio data: I. A new YOLO-inspired source detection method applied to the SKAO SDC1
No full textInternational audienceContext. The upcoming Square Kilometer Array (SKA) will set a new standard regarding data volume generated by an astronomical instrument, which is likely to challenge widely adopted data-analysis tools that scale inadequately with the data size.Aims. The aim of this study is to develop a new source detection and characterization method for massive radio astronomical datasets based on modern deep-learning object detection techniques. For this, we seek to identify the specific strengths and weaknesses of this type of approach when applied to astronomical data.Methods. We introduce YOLO-CIANNA, a highly customized deep-learning object detector designed specifically for astronomical datasets. In this paper, we present the method and describe all the elements introduced to address the specific challenges of radio astronomical images. We then demonstrate the capabilities of this method by applying it to simulated 2D continuum images from the SKA observatory Science Data Challenge 1 (SDC1) dataset.Results. Using the SDC1 metric, we improve the challenge-winning score by +139% and the score of the only other post-challenge participation by +61%. Our catalog has a detection purity of 94% while detecting 40–60% more sources than previous top-score results, and exhibits strong characterization accuracy. The trained model can also be forced to reach 99% purity in post-process and still detect 10–30% more sources than the other top-score methods. It is also computationally efficient, with a peak prediction speed of 500 images of 512×512 pixels per second on a single GPU.Conclusions. YOLO-CIANNA achieves state-of-the-art detection and characterization results on the simulated SDC1 dataset and is expected to transfer well to observational data from SKA precursors
Bouddha. L'expérience du Sensible
No full textInternational audienceNé en Inde au 5e siècle avant notre ère, le bouddhisme s'est rapidement diffusé à travers l'Asie et a inspiré d'innombrables formes artistiques. Des premières statues en Inde aux thangka tibétains, n passant par les porcelaines de Chine, les peintures du Japon et autres sculptures en bois, en pierre ou en bronze de Thaïlande ou d'ailleurs, ces oeuvres illustrent la capacité des artistes à adapter l'art bouddhique aux traditions esthétiques locales. Loin d'être de simples objets d'art ou de collection, ces oeuvres sont des témoins de pratiques spirituelles et rituelles. Elles servent ainsi de supports à la méditation, favorisent la réflexion intérieure et l'élévation spirituelle.Puisant dans la richesse des collections du Musée royal de Mariemont, cet ouvrage propose de découvrir les multiples représentations du Bouddha, sa légende et ses enseignements, la diversité des figures du panthéon bouddhique telles que le bouddha de la médecine ou le bodhisattva de la compassion, Avalokitesvara, leurs attributs et leurs fonctions. Il invite également à revivre la rencontre de la Belgique avec le bouddhisme. Les objets ici réunis pour la première fois - et réévalués à l'occasion de la restauration d'un grand nombre d'entre eux - constituent le catalogue d'une exposition qui transcende les cultures, le temps et l'espace, pour nous inspirer, nous guider et provoquer notre sensibilité