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A Fortran-Python interface for integrating machine learning parameterization into earth system models
No full textParameterizations in earth system models (ESMs) are subject to biases and uncertainties arising from subjective empirical assumptions and incomplete understanding of the underlying physical processes. Recently, the growing representational capability of machine learning (ML) in solving complex problems has spawned immense interests in climate science applications. Specifically, ML-based parameterizations have been developed to represent convection, radiation, and microphysics processes in ESMs by learning from observations or high-resolution simulations, which have the potential to improve the accuracies and alleviate the uncertainties. Previous works have developed some surrogate models for these processes using ML. These surrogate models need to be coupled with the dynamical core of ESMs to investigate the effectiveness and their performance in a coupled system. In this study, we present a novel Fortran–Python interface designed to seamlessly integrate ML parameterizations into ESMs. This interface showcases high versatility by supporting popular ML frameworks like PyTorch, TensorFlow, and scikit-learn. We demonstrate the interface's modularity and reusability through two cases: an ML trigger function for convection parameterization and an ML wildfire model. We conduct a comprehensive evaluation of memory usage and computational overhead resulting from the integration of Python codes into the Fortran ESMs. By leveraging this flexible interface, ML parameterizations can be effectively developed, tested, and integrated into ESMs.Parameterizations in earth system models (ESMs) are subject to biases and uncertainties arising from subjective empirical assumptions and incomplete understanding of the underlying physical processes. Recently, the growing representational capability of machine learning (ML) in solving complex problems has spawned immense interests in climate science applications. Specifically, ML-based parameterizations have been developed to represent convection, radiation, and microphysics processes in ESMs by learning from observations or high-resolution simulations, which have the potential to improve the accuracies and alleviate the uncertainties. Previous works have developed some surrogate models for these processes using ML. These surrogate models need to be coupled with the dynamical core of ESMs to investigate the effectiveness and their performance in a coupled system. In this study, we present a novel Fortran–Python interface designed to seamlessly integrate ML parameterizations into ESMs. This interface showcases high versatility by supporting popular ML frameworks like PyTorch, TensorFlow, and scikit-learn. We demonstrate the interface's modularity and reusability through two cases: an ML trigger function for convection parameterization and an ML wildfire model. We conduct a comprehensive evaluation of memory usage and computational overhead resulting from the integration of Python codes into the Fortran ESMs. By leveraging this flexible interface, ML parameterizations can be effectively developed, tested, and integrated into ESMs.A
Le petit commerce de l'indépendance : une sociologie de la librairie au début du XXIe siècle /
No full text"On a pu penser les librairies menacées de disparition par l'efficacité des algorithmes de recommandation et des plateformes de vente en ligne. Leur rôle semble pourtant réaffirmé en ce début de XXIe siècle : valorisées dans les médias, plébiscitées par leur clientèle, soutenues par les pouvoirs publics, portées par de nouveaux profils de libraires, elles bénéficient d'un statut particulier parmi les commerces culturels. Leur réussite tient au fait qu'elles ont misé sur le conseil et la singularité de l'expérience en magasin. Elles ont su mettre en avant une identité "indépendante" qui, malgré le flou qui l'entoure, constitue une ressource précieuse pour se différencier dans le domaine culturel. Les librairies représentent ainsi bien plus que des lieux où acheter et découvrir des livres : leur succès participe de la montée en puissance de modes de consommation alternatifs, plus "authentiques" et incarnés. Le livre s'appuie sur une enquête menée en France, pays de "l'exception culturelle", et en Grande-Bretagne, l'un des marchés du livre les plus dérégulés au monde, et mobilise un vaste matériel empirique (entretiens, observations, corpus médiatique), Il met en valeur des traits communs à l'évolution du commerce du Livre des deux côtés de la Manche et permet de comprendre pourquoi les librairies continuent d'incarner un modèle désirable d'accès aux ouvrages à l'heure du "tout numérique.""--Page 4 of cover.Includes bibliographical references (pages 195-204) and indexes."On a pu penser les librairies menacées de disparition par l'efficacité des algorithmes de recommandation et des plateformes de vente en ligne. Leur rôle semble pourtant réaffirmé en ce début de XXIe siècle : valorisées dans les médias, plébiscitées par leur clientèle, soutenues par les pouvoirs publics, portées par de nouveaux profils de libraires, elles bénéficient d'un statut particulier parmi les commerces culturels. Leur réussite tient au fait qu'elles ont misé sur le conseil et la singularité de l'expérience en magasin. Elles ont su mettre en avant une identité "indépendante" qui, malgré le flou qui l'entoure, constitue une ressource précieuse pour se différencier dans le domaine culturel. Les librairies représentent ainsi bien plus que des lieux où acheter et découvrir des livres : leur succès participe de la montée en puissance de modes de consommation alternatifs, plus "authentiques" et incarnés. Le livre s'appuie sur une enquête menée en France, pays de "l'exception culturelle", et en Grande-Bretagne, l'un des marchés du livre les plus dérégulés au monde, et mobilise un vaste matériel empirique (entretiens, observations, corpus médiatique), Il met en valeur des traits communs à l'évolution du commerce du Livre des deux côtés de la Manche et permet de comprendre pourquoi les librairies continuent d'incarner un modèle désirable d'accès aux ouvrages à l'heure du "tout numérique.""--Page 4 of cover."Sophie Noël est sociologue du livre et de l'édition et professeure à l'université Paris-Panthéon-Assas (Institut français de presse-Carism). Elle a notamment publié L'Édition indépendante critique : engagements ; politiques et intellectuels (Presses de l'Enssib, nouvelle édition 2021)"--Page 4 of cover
Maximizing immunopeptidomics-based bacterial epitope discovery by multiple search engines and rescoring
No full textMass spectrometry-based discovery of bacterial immunopeptides presented by infected cells allows untargeted discovery of bacterial antigens that can serve as vaccine candidates. However, reliable identification of bacterial epitopes is challenged by their extremely low abundance. Here, we describe an optimized bioinformatic framework to enhance the confident identification of bacterial immunopeptides. Immunopeptidomics data of cell cultures infected with Listeria monocytogenes were searched by four different search engines, PEAKS, Comet, Sage and MSFragger, followed by data-driven rescoring with MS2Rescore. Compared with individual search engine results, this integrated workflow boosted immunopeptide identification by an average of 27% and led to the high-confidence detection of 18 additional bacterial peptides (+27%) matching 15 different Listeria proteins (+36%). Despite the strong agreement between the search engines, a small number of spectra (Listeria monocytogenes were searched by four different search engines, PEAKS, Comet, Sage and MSFragger, followed by data-driven rescoring with MS2Rescore. Compared with individual search engine results, this integrated workflow boosted immunopeptide identification by an average of 27% and led to the high-confidence detection of 18 additional bacterial peptides (+27%) matching 15 different Listeria proteins (+36%). Despite the strong agreement between the search engines, a small number of spectra (<1%) had ambiguous matches to multiple peptides and were excluded to ensure high-confidence identifications. Finally, we demonstrate our workflow with sensitive timsTOF SCP data acquisition and find that rescoring, now with inclusion of ion mobility features, identifies 76% more peptides compared to Q Exactive HF acquisition. Together, our results demonstrate how integration of multiple search engine results along with data-driven rescoring maximizes immunopeptide identification, boosting the detection of high-confidence bacterial epitopes for vaccine development.A
Titchmarsh theorems on Damek-Ricci spaces via moduli of continuity of higher order
No full textA classical theorem of Titchmarsh relates the 2-Lipschitz functions and decay of the Fourier transform of the functions. In this note, we prove the Titchmarsh theorem for Damek–Ricci space (also known as harmonic groups) via moduli of continuity of higher orders. We also prove an analogue of another Titchmarsh theorem which provides integrability properties of the Fourier transform for functions in the Hölder Lipschitz spaces.A classical theorem of Titchmarsh relates the 2-Lipschitz functions and decay of the Fourier transform of the functions. In this note, we prove the Titchmarsh theorem for Damek–Ricci space (also known as harmonic groups) via moduli of continuity of higher orders. We also prove an analogue of another Titchmarsh theorem which provides integrability properties of the Fourier transform for functions in the Hölder Lipschitz spaces.A
C-band radar measurements in a snow-covered boreal forest environment
No full textSled-based side-looking C-band radar profiles were collected around Fairbanks, Alaska, in March 2023 during the NASA SnowEx campaign to improve the conceptual understanding of C-band radar wave interactions with snow in a boreal forest environment. Seven transects with different vegetation and ground conditions were studied. Significant volume scattering from snow was observed in this shallow snowpack, indicating sensitivity at lower snow depths (SDs) which are common in high-latitude snowpacks. Manual removal of the snowpack decreased the backscatter by more than 2 dB in all polarizations, with a larger decrease in the cross-polarization, supporting the potential use of Sentinel-1 to retrieve SD.Sled-based side-looking C-band radar profiles were collected around Fairbanks, Alaska, in March 2023 during the NASA SnowEx campaign to improve the conceptual understanding of C-band radar wave interactions with snow in a boreal forest environment. Seven transects with different vegetation and ground conditions were studied. Significant volume scattering from snow was observed in this shallow snowpack, indicating sensitivity at lower snow depths (SDs) which are common in high-latitude snowpacks. Manual removal of the snowpack decreased the backscatter by more than 2 dB in all polarizations, with a larger decrease in the cross-polarization, supporting the potential use of Sentinel-1 to retrieve SD.A
Euclid preparation : LVIII. Detecting extragalactic globular clusters in the Euclid survey
No full textExtragalactic globular clusters (EGCs) are an abundant and powerful tracer of galaxy dynamics and formation, and their own formation and evolution is also a matter of extensive debate. The compact nature of globular clusters means that they are hard to spatially resolve and thus study outside the Local Group. In this work we have examined how well EGCs will be detectable in images from the Euclid telescope, using both simulated pre-launch images and the first early-release observations of the Fornax galaxy cluster. The Euclid Wide Survey will provide high-spatial resolution VIS imaging in the broad IE band as well as near-infrared photometry (YE, JE, and HE). We estimate that the 24 719 known galaxies within 100 Mpc in the footprint of the Euclid survey host around 830 000 EGCs of which about 350 000 are within the survey's detection limits. For about half of these EGCs, three infrared colours will be available as well. For any galaxy within 50 Mpc the brighter half of its GC luminosity function will be detectable by the Euclid Wide Survey. The detectability of EGCs is mainly driven by the residual surface brightness of their host galaxy. We find that an automated machine-learning EGC-classification method based on real Euclid data of the Fornax galaxy cluster provides an efficient method to generate high purity and high completeness GC candidate catalogues. We confirm that EGCs are spatially resolved compared to pure point sources in VIS images of Fornax. Our analysis of both simulated and first on-sky data show that Euclid will increase the number of GCs accessible with high-resolution imaging substantially compared to previous surveys, and will permit the study of GCs in the outskirts of their hosts. Euclid is unique in enabling systematic studies of EGCs in a spatially unbiased and homogeneous manner and is primed to improve our understanding of many understudied aspects of GC astrophysics.Extragalactic globular clusters (EGCs) are an abundant and powerful tracer of galaxy dynamics and formation, and their own formation and evolution is also a matter of extensive debate. The compact nature of globular clusters means that they are hard to spatially resolve and thus study outside the Local Group. In this work we have examined how well EGCs will be detectable in images from the Euclid telescope, using both simulated pre-launch images and the first early-release observations of the Fornax galaxy cluster. The Euclid Wide Survey will provide high-spatial resolution VIS imaging in the broad IE band as well as near-infrared photometry (YE, JE, and HE). We estimate that the 24 719 known galaxies within 100 Mpc in the footprint of the Euclid survey host around 830 000 EGCs of which about 350 000 are within the survey's detection limits. For about half of these EGCs, three infrared colours will be available as well. For any galaxy within 50 Mpc the brighter half of its GC luminosity function will be detectable by the Euclid Wide Survey. The detectability of EGCs is mainly driven by the residual surface brightness of their host galaxy. We find that an automated machine-learning EGC-classification method based on real Euclid data of the Fornax galaxy cluster provides an efficient method to generate high purity and high completeness GC candidate catalogues. We confirm that EGCs are spatially resolved compared to pure point sources in VIS images of Fornax. Our analysis of both simulated and first on-sky data show that Euclid will increase the number of GCs accessible with high-resolution imaging substantially compared to previous surveys, and will permit the study of GCs in the outskirts of their hosts. Euclid is unique in enabling systematic studies of EGCs in a spatially unbiased and homogeneous manner and is primed to improve our understanding of many understudied aspects of GC astrophysics.A
Coalition building for a just transition : examining the convergence of trade unions and social movements in Flanders
No full textThe rise of the Just Transition concept offers the potential to reconcile the demands of trade unions and environmental movements in a united front. However, little empirical research exists on the potential of Just Transition for alliance building. Therefore, this study examines how differing Just Transition visions come together in a coalition between Flemish trade unions, environmental and other social movements by zooming in on the case of Reset.Vlaanderen (Reset.Flanders) as an institutionalised Just Transition coalition. By adopting Environmental Labour Studies and Social Movement Theory on alliance building, this study takes into account four overarching explanatory dimensions, context, resources, ideas and performances, to analyse how a coalition between the divergent Just Transition visions of labour and environmental movements is constructed.The rise of the Just Transition concept offers the potential to reconcile the demands of trade unions and environmental movements in a united front. However, little empirical research exists on the potential of Just Transition for alliance building. Therefore, this study examines how differing Just Transition visions come together in a coalition between Flemish trade unions, environmental and other social movements by zooming in on the case of Reset.Vlaanderen (Reset.Flanders) as an institutionalised Just Transition coalition. By adopting Environmental Labour Studies and Social Movement Theory on alliance building, this study takes into account four overarching explanatory dimensions, context, resources, ideas and performances, to analyse how a coalition between the divergent Just Transition visions of labour and environmental movements is constructed.C