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Copyright of Travaux (00411906) is the property of COM'1 EVIDENCE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Travaux (00411906) is the property of COM'1 EVIDENCE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As industries of all kinds grapple with how to put artificial intelligence to work, you'd be hard pressed to find a better immediate fit for the emerging technology than the [...]

Copyright of Travaux (00411906) is the property of COM'1 EVIDENCE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Photinus pyralisluciferase (FLuc) has proven a valuable tool for bioluminescence imaging, but much of the light emitted from the native enzyme is absorbed by endogenous biomolecules. Thus, luciferases displaying red-shifted emission enable higher resolution during deep-tissue imaging. A robust model of how protein structure determines emission color would greatly aid the engineering of red-shifted mutants, but no consensus has been reached to date. In this work, we applied deep mutational scanning to systematically assess 20 functionally important amino acid positions on FLuc for red-shifting mutations, predicting that an unbiased approach would enable novel contributions to this debate. We report dozens of red-shifting mutations as a result, a large majority of which have not been previously identified. Further characterization revealed that mutations N229T and T352M, in particular, bring about unimodal emission with the majority of photons being >600 nm. The red-shifting mutations identified by this high-throughput approach provide strong biochemical evidence for the multiple-emitter mechanism of color determination and point to the importance of a water network in the enzyme binding pocket for altering the emitter ratio. This work provides a broadly applicable mutational data set tying FLuc structure to emission color that contributes to our mechanistic understanding of emission color determination and should facilitate further engineering of improved probes for deep-tissue imaging.

We introduce a novel method for measurement of the absorbed power density (APD) above 6 GHz, accounting for antenna/body interaction. A reflectivity-based thin planar solid phantom is used to mimic the scattering characteristics of human skin. This allows to perturb the antenna under test (AUT) in a similar way as it would be perturbed by the presence of the human body. The lower electromagnetic losses in the phantom medium result in an enhanced transmission through the phantom facilitating free-space ${E}$ -field vector measurement on the opposite to the AUT side of the phantom. The measured ${E}$ -field is backpropagated in space to retrieve APD using a plane-wave spectrum (PWS) technique. The proposed method is validated at 60 GHz using reference antennas, namely, a cavity-fed dipole array and pyramidal horn with a slot array. A very good agreement is demonstrated between the target APD at the air/skin interface (peak, averaged, and spatial distribution) and the one reconstructed from the simulated and measured ${E}$ -field. The maximum relative deviations between the computed and measured peak ( $p\text {APD}$ ), 1 cm2 peak spatial average ( $ps\text {APD}_{1\,\text {cm}^{2}}$ ), and 4 cm2 peak spatial average ( $ps\text {APD}_{4\,\text {cm}^{2}}$ ) are 13.2% (0.55 dB), 14.9% (0.6 dB), and 15.7% (0.63 dB), respectively. The results demonstrate that the proposed technique is promising for experimental dosimetry and compliance testing of wireless devices operating above 6 GHz.

In the context of global warming, it is crucial to focus on the effects of temperature on the emergence of new lineages of endemic pathogen species, such as Puccinia striiformisf. sp. tritici(Pst) the causal agent of yellow rust on wheat. We characterized the thermal aptitude of representative isolates from the most recent common European Pstraces. We assessed two key aggressiveness components—infection efficiency (IE) and latency period (LP)—under warm and cold thermal regimes, comparing 10 Pstisolates collected from 2010 to 2020 with three “old” reference isolates. The significant differences observed suggest that this species has the potential to adapt to temperature changes, but that such adaptation probably did not drive the establishment of neither the previously dominant races ‘Warrior’ and ‘Warrior(-)’, nor the following most recent races. These races display “generalist” behavior with respect to temperature, with ‘Warrior(-)’ showing no more aggressiveness than the races replaced since the 1990s. The differences in competitive success between emerging Pstlineages are probably due to the deployment of resistance genes in wheat and the advantages of new forms of virulence emerging independently of thermal adaptability. However, variations in thermal adaptability for both aggressiveness components suggested an impact of geographic origin within the ‘Warrior’ and ‘Warrior(-)’ races, as previously reported for the “old” reference isolates. Furthermore, the independence of thermal adaptability established for IE and LP implies that the effects of temperature may depend on the stage of the epidemic (early or late), potentially modifying seasonal dynamics.

Abstract:This article revisits the multifaceted contribution of Henri Decoin to French cinema's rich history through the lens of sport and auteurism. Decoin, who began his career as a professional swimmer in the 1910s, turned to sports journalism during the 1920s before switching his focus to filmmaking until the mid-1960s. Despite an extensive cinematic oeuvre, film scholars are yet to conduct a systematic examination of his influence as a director. By taking a closer look at the recurring sporting motifs and symbolism present in his work, we argue that Decoin not only ought to be seen as a genuine auteur, but also as one of French cinema's most versatile players.

Copyright of Travaux (00411906) is the property of COM'1 EVIDENCE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water vapour atmospheres with content equivalent to the Earth’s oceans, resulting from impacts1or a high insolation2,3, were found to yield a surface magma ocean4,5. This was, however, a consequence of assuming a fully convective structure2–11. Here, we report using a consistent climate model that pure steam atmospheres are commonly shaped by radiative layers, making their thermal structure strongly dependent on the stellar spectrum and internal heat flow. The surface is cooler when an adiabatic profile is not imposed; melting Earth’s crust requires an insolation several times higher than today, which will not happen during the main sequence of the Sun. Venus’s surface can solidify before the steam atmosphere escapes, which is the opposite of previous works4,5. Around the reddest stars (Teff<  3,000 K), surface magma oceans cannot form by stellar forcing alone, whatever the water content. These findings affect observable signatures of steam atmospheres and exoplanet mass–radius relationships, drastically changing current constraints on the water content of TRAPPIST-1 planets. Unlike adiabatic structures, radiative–convective profiles are sensitive to opacities. New measurements of poorly constrained high-pressure opacities, in particular far from the H2O absorption bands, are thus necessary to refine models of steam atmospheres, which are important stages in terrestrial planet evolution.

Photochemistry is a fundamental process of planetary atmospheres that regulates the atmospheric composition and stability1. However, no unambiguous photochemical products have been detected in exoplanet atmospheres so far. Recent observations from the JWST Transiting Exoplanet Community Early Release Science Program2,3found a spectral absorption feature at 4.05 μm arising from sulfur dioxide (SO2) in the atmosphere of WASP-39b. WASP-39b is a 1.27-Jupiter-radii, Saturn-mass (0.28 MJ) gas giant exoplanet orbiting a Sun-like star with an equilibrium temperature of around 1,100 K (ref. 4). The most plausible way of generating SO2in such an atmosphere is through photochemical processes5,6. Here we show that the SO2distribution computed by a suite of photochemical models robustly explains the 4.05-μm spectral feature identified by JWST transmission observations7with NIRSpec PRISM (2.7σ)8and G395H (4.5σ)9. SO2is produced by successive oxidation of sulfur radicals freed when hydrogen sulfide (H2S) is destroyed. The sensitivity of the SO2feature to the enrichment of the atmosphere by heavy elements (metallicity) suggests that it can be used as a tracer of atmospheric properties, with WASP-39b exhibiting an inferred metallicity of about 10× solar. We further point out that SO2also shows observable features at ultraviolet and thermal infrared wavelengths not available from the existing observations.

The ever-increasing number of available microbial genomes and metagenomes provides new opportunities to investigate the links between niche partitioning and genome evolution in the ocean, especially for the abundant and ubiquitous marine picocyanobacteria Prochlorococcusand Synechococcus. Here, by combining metagenome analyses of the TaraOceans dataset with comparative genomics, including phyletic patterns and genomic context of individual genes from 256 reference genomes, we show that picocyanobacterial communities thriving in different niches possess distinct gene repertoires. We also identify clusters of adjacent genes that display specific distribution patterns in the field (eCAGs) and are thus potentially involved in the same metabolic pathway and may have a key role in niche adaptation. Several eCAGs are likely involved in the uptake or incorporation of complex organic forms of nutrients, such as guanidine, cyanate, cyanide, pyrimidine, or phosphonates, which might be either directly used by cells, for example for the biosynthesis of proteins or DNA, or degraded to inorganic nitrogen and/or phosphorus forms. We also highlight the enrichment of eCAGs involved in polysaccharide capsule biosynthesis in Synechococcuspopulations thriving in both nitrogen- and phosphorus-depleted areas vs. low-iron (Fe) regions, suggesting that the complexes they encode may be too energy-consuming for picocyanobacteria thriving in the latter areas. In contrast, Prochlorococcuspopulations thriving in Fe-depleted areas specifically possess an alternative respiratory terminal oxidase, potentially involved in the reduction of Fe(III) to Fe(II). Altogether, this study provides insights into how phytoplankton communities populate oceanic ecosystems, which is relevant to understanding their capacity to respond to ongoing climate change.

La spécialité de cardiopédiatrie assure le suivi médical des patients présentant des pathologies cardio-vasculaires, de 0 à 18 ans. Les thérapeutiques médicamenteuses sont complexes et dépendent du type de pathologie et de l’âge du patient. Les patients sont vulnérables et les prises en charge sont à risque d’erreurs médicamenteuses. La pharmacie clinique peut permettre de réduire ce risque.

Close-in giant exoplanets with temperatures greater than 2,000 K (‘ultra-hot Jupiters’) have been the subject of extensive efforts to determine their atmospheric properties using thermal emission measurements from the Hubble Space Telescope (HST) and Spitzer Space Telescope1–3. However, previous studies have yielded inconsistent results because the small sizes of the spectral features and the limited information content of the data resulted in high sensitivity to the varying assumptions made in the treatment of instrument systematics and the atmospheric retrieval analysis3–12. Here we present a dayside thermal emission spectrum of the ultra-hot Jupiter WASP-18b obtained with the NIRISS13instrument on the JWST. The data span 0.85 to 2.85 μm in wavelength at an average resolving power of 400 and exhibit minimal systematics. The spectrum shows three water emission features (at >6σconfidence) and evidence for optical opacity, possibly attributable to H−, TiO and VO (combined significance of 3.8σ). Models that fit the data require a thermal inversion, molecular dissociation as predicted by chemical equilibrium, a solar heavy-element abundance (‘metallicity’, M/H=1.03−0.51+1.11times solar) and a carbon-to-oxygen (C/O) ratio less than unity. The data also yield a dayside brightness temperature map, which shows a peak in temperature near the substellar point that decreases steeply and symmetrically with longitude towards the terminators.

Transmission spectroscopy1–3of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations’ relatively narrow wavelength range and spectral resolving power, which precluded the unambiguous identification of other chemical species—in particular the primary carbon-bearing molecules6,7. Here we report a broad-wavelength 0.5–5.5 µm atmospheric transmission spectrum of WASP-39b8, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, measured with the JWST NIRSpec’s PRISM mode9as part of the JWST Transiting Exoplanet Community Early Release Science Team Program10–12. We robustly detect several chemical species at high significance, including Na (19σ), H2O (33σ), CO2(28σ) and CO (7σ). The non-detection of CH4, combined with a strong CO2feature, favours atmospheric models with a super-solar atmospheric metallicity. An unanticipated absorption feature at 4 µm is best explained by SO2(2.7σ), which could be a tracer of atmospheric photochemistry. These observations demonstrate JWST’s sensitivity to a rich diversity of exoplanet compositions and chemical processes.

Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining the dominant chemical processes at work and, if in equilibrium, revealing planet formation histories. Transmission spectroscopy (for example, refs. 1,2) provides the necessary means by constraining the abundances of oxygen- and carbon-bearing species; however, this requires broad wavelength coverage, moderate spectral resolution and high precision, which, together, are not achievable with previous observatories. Now that JWST has commenced science operations, we are able to observe exoplanets at previously uncharted wavelengths and spectral resolutions. Here we report time-series observations of the transiting exoplanet WASP-39b using JWST’s Near InfraRed Camera (NIRCam). The long-wavelength spectroscopic and short-wavelength photometric light curves span 2.0–4.0 micrometres, exhibit minimal systematics and reveal well defined molecular absorption features in the planet’s spectrum. Specifically, we detect gaseous water in the atmosphere and place an upper limit on the abundance of methane. The otherwise prominent carbon dioxide feature at 2.8 micrometres is largely masked by water. The best-fit chemical equilibrium models favour an atmospheric metallicity of 1–100-times solar (that is, an enrichment of elements heavier than helium relative to the Sun) and a substellar C/O ratio. The inferred high metallicity and low C/O ratio may indicate significant accretion of solid materials during planet formation (for example, refs. 3,4,) or disequilibrium processes in the upper atmosphere (for example, refs. 5,6).

Measuring the abundances of carbon and oxygen in exoplanet atmospheres is considered a crucial avenue for unlocking the formation and evolution of exoplanetary systems1,2. Access to the chemical inventory of an exoplanet requires high-precision observations, often inferred from individual molecular detections with low-resolution space-based3–5and high-resolution ground-based6–8facilities. Here we report the medium-resolution (R≈ 600) transmission spectrum of an exoplanet atmosphere between 3 and 5 μm covering several absorption features for the Saturn-mass exoplanet WASP-39b (ref. 9), obtained with the Near Infrared Spectrograph (NIRSpec) G395H grating of JWST. Our observations achieve 1.46 times photon precision, providing an average transit depth uncertainty of 221 ppm per spectroscopic bin, and present minimal impacts from systematic effects. We detect significant absorption from CO2(28.5σ) and H2O (21.5σ), and identify SO2as the source of absorption at 4.1 μm (4.8σ). Best-fit atmospheric models range between 3 and 10 times solar metallicity, with sub-solar to solar C/O ratios. These results, including the detection of SO2, underscore the importance of characterizing the chemistry in exoplanet atmospheres and showcase NIRSpec G395H as an excellent mode for time-series observations over this critical wavelength range10.