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On the validity of the Moes iso-viscous - Rigid film thickness prediction, the influence of domain starvation and the parabolic geometry approximation
No full textThe validity of the Isoviscous Rigid film thickness prediction by Moes is analysed as well as the validity of the parabolic geometry approximating the spherical geometry
Measuring shade use of dairy cattle at pasture with an on-cow light sensor: a case study
No full textInternational audienceGrazing cows preferentially access shade to shield against the sun. However, the conditions that provide cows with optimal shade access and use (e.g. no competition for access to shade) are still unknown. Continuous monitoring of shade use by grazing cattle could help to understand how and when cows use shade resources. The aim of this study was to validate a method based on a light sensor (HOBO Pendant MX2202) attached to the back (on the transverse processes of the lumbar vertebrae) of 7 dairy cows at pasture to continuously record their use of natural shade for research purposes. Live behavioral observations of shade use and cow posture were recorded in summer (June to September, between 9 am and 6 pm). Based on the behavioral observation data, we determined thresholds in lux to discriminate between cows in shade and cows in sun on a randomly-generated training dataset representing 15 % of the initial dataset. This process was repeated 100 times, generating 100 thresholds and threshold performances. Data loss due to sensor loss or battery discharge was 9 %, which is acceptable. The thresholds ranged from 15,688 to 40556 lx: sensitivity ranged from 92.0 % to 99.8 % and specificity ranged from 88.7 % to 99.9 %, showing that the performances were robust to threshold variation within this range. This study demonstrates that an efficient threshold to discriminate cows in shade from cows in the sun can be determined via a relatively short (about 12 h) series of live observations. As performances seem to be slightly lower for lying cows than for standing cows (mean false-positive rate is 7.4 % for lying cows versus 1.8 % for standing cows), future studies should consider the posture (which can also be monitored continuously with other sensors such as accelerometer installed on the legs or on the neck collar of the cows)
Binding energy of compact stars and their non-radial oscillations
No full textInternational audienceIn the past years, a significant effort has been made with the scope of determining correlations, involving compact star properties, that are independent of the nuclear equation of state. Such universal relations are of utmost importance as they allow for the imposition of constraints on stellar properties without directly measuring them and they may also serve as a probe of General Relativity. In the present study, we investigated the possible existence of a universal relation between the binding energy of compact stars and the frequency of their non-radial oscillations. The main motivation was related to the fact that both of the aforementioned quantities might be measured in the occurrence of a supernova explosion. Interestingly, we found that there is a empirical relation between the oscillation frequency and the binding energy for both and modes, assuming hadronic stellar matter. The inclusion of hybrid equations of state, incorporating sharp phase transitions, was shown to result into deviations from the aforementioned quasi-universal relation
Mapping food practices in rural Italy: consumer diversity as a key to informing sustainable food policy
No full textInternational audienceThe global food system looms as a major contributor to a wide range of increasingly threatening sustainability challenges which encompass the environment, human health, justice and ethics. Hitherto food policy has relied on behavioural theories to encourage consumers towards sustainable food practices, albeit with limited success. This study delves into consumers' daily choices and attitudes to food, using theory of practice as a framework. Designed as a case study located in the Valle dei Laghi biodistrict, Italy, thirty-six semi-structured interviews with open-ended questions were conducted with consumers and producers. Direct observation was used to enhance the validity and credibility of the results. In addition to the food citizen and passive consumer widely discussed in literature, the existence of two additional consumer profiles, termed the pragmatic consumer and the traditiondriven consumer, was identified. The pragmatic consumer, despite an understanding of sustainability related issues, adopts food choices rooted in convenience and opportunism. The tradition-driven consumer, in contrast, deploys unconsciously highly sustainable practices that can be traced back to the notion of quiet sustainability. In this article we discuss the significance of these findings for the design of policy interventions tailored to sustain a transformation towards sustainable food systems and propose practice-oriented policy measures to adjust and complement current policy
Search for resonances decaying to an anomalous jet and a Higgs boson in proton-proton collisions at = 13 TeV
No full textInternational audienceThis paper presents a search for new physics through the process where a new massive particle, X, decays into a Higgs boson and a second particle, Y. The Higgs boson subsequently decays into a bottom quark-antiquark pair, reconstructed as a single large-radius jet. The decay products of Y are also assumed to produce a single large-radius jet. The identification of the Y particle is enhanced by computing the anomaly score of its candidate jet using an autoencoder, which measures deviations from typical QCD multijet jets. This allows a simultaneous search for multiple Y decay scenarios within a single analysis. In the main benchmark process, Y is a scalar particle that decays into WW. Two other benchmark processes are also considered, where Y is a scalar particle decaying into a light quark-antiquark pair, or into a top quark-antiquark pair. The last benchmark considers Y as a hadronically decaying top quark, arising from the decay of a vector-like quark into a top quark and a Higgs boson. Data recorded by the CMS experiment at a center-of-mass energy of 13 TeV in 20162018, and corresponding to an integrated luminosity of 138 fb, are analyzed. No significant excess is observed, and upper limits on the benchmark signal cross section for various masses of X and Y, at 95% confidence level, are placed
Women’s Europeanist networks and the gendering of EEC labour policies during the long 1960s (1957–74)
No full textInternational audienceHistorians and political scientists have long traced the introduction of a reflection on the gendered impact of European public policies back to the mid-1970s. This was linked in particular to the attempt to reduce inequalities between men and women at work, and to the adoption of European legislation in this area, based on directives designed to ensure the application of Article 119 of the Treaty of Rome. This legal approach provides little explanation of the reasons, actors and modalities for putting gender issues on the agenda of the European Economic Communities (EEC). Based mostly on the archives of women’s associations linked to the European Movement, and secondarily on the holdings of several European institutions (Commission, Parliament, Council, Economic and Social Committee), this article offers an original top-down and bottom-up analysis of the process of gendering EEC policies between 1957 and 1974. It contributes to the analysis of the economisation of the EEC social policies and shows that, for women Europeanist activists of the 1960s, gender equality could not be reduced to the issue of wages. Gendering European policies neither represented a linear process of framing of social policies under the economic goals of the EEC, nor was it an insignificant tool in the affirmation of the European institutions vis-à-vis the Member States. Eventually, studying the agency of women’s associations in the inclusion of gender in EEC labour policies allows the article to shed new light on the citizen impulses in the European integration process, from the 1960s onwards
« Aux conscrits » : les paradoxes du prosélytisme antimilitariste (1902-1908)
No full textInternational audienceAfin de rendre compte des paradoxes du prosélytisme antimilitariste entre 1902 et 1908, cet article s’intéresse à la façon dont les membres de l’ Association Internationale Antimilitariste influencent le consentement à la guerre d’une génération entière, à travers un discours didactique qui reflète une tension entre « refus de servir » et « refus de parvenir ». Il montre ensuite comment ces différents types de refus de l’autorité coexistent à travers des dialogues entre un jeune soldat et ses contemporains, présents dans des brochures de propagande qui prennent la forme de lettres ouvertes ou de pièces de théâtre. Finalement, il apparaît que le prosélytisme antimilitariste du début du xx e siècle se fonde sur une représentation caricaturale du conscrit
Quels leviers d'adaptation de l'agriculture au changement climatique ? Inventaire et analyse des projets de recherche et développement en région Auvergne Rhône Alpes.
No full textClimate forecasts predict a general rise in temperatures and an intensification of droughts, especially in Mediterranean zones moving northward in France. By 2050, the climate of the Auvergne-Rhône-Alpes region is expected to become more Mediterranean, and its agriculture will have to face new meteorological challenges. Moreover, given the globalized system in which this agriculture operates, this is not the only challenge it will encounter, and an agroecological transition is underway to meet these food, health, environmental, economic, and social issues, among others.In this context, the AgriAuRA2050 project aims to design viable production methods and practices to ensure the sustainability of farms and the economic viability of three sectors in the Auvergne-Rhône-Alpes region - field crops, herbivore livestock, and arboriculture - by 2050, in a context of climate change and agroecological transition. As part of this project, an inventory of structured projects in the Auvergne-Rhône-Alpes region was carried out to summarize the known responses of crop and livestock systems to non-conventional practices in the region. The objective was to identify the the levers used by projects in the region to adapt agriculture to climate change, and in particular to water constraints, which are likely to be a major challenge in the coming years. A characterization of these levers and a summary of the results obtained were also carried out.Research carried out mainly on the Internet identified 65 projects and highlighted 27 main levers grouped into four main categories: genetics, agricultural practices, functional diversity, and miscellaneous subjects for more forward-looking projects not focused on specific levers. A wealth of information was collected on these projects, especially through discussions with coordinators, in order to characterize them. Additionally, complete or partial results were obtained for 31 projects, and were the subject of a qualitative analysis summarizing their overall positive, negative, or neutral effects based on the lever studied and the variable measured.The levers studied were categorized by the sectors testing them. Thus, the miscellaneous subjects are the only ones to include projects involving several sectors, and otherwise only include livestock projects. The other groups include all three sectors, with more field crop projects for genetic levers, more arboriculture projects for agricultural practices, and a more balanced distribution for functional diversity levers. Regarding implementation dates and durations, projects focused on genetic or agricultural levers tend to be short, ongoing, and started after 2015, often tested on a reduced scale, primarily at specific sites. On the other hand, projects of miscellaneous subjects tend to be longer, also ongoing, and initiated between 2000 and 2020. They are implemented on a larger scale, often at the departmental or regional level, as are the projects on functional diversity, which also have the highest proportion of completed projects. These are relatively short and were typically initiated after 2015, although some are older. The structures managing these projects vary between groups. For example, research-focused institutions are more prominent in the agricultural practices and genetics groups, while the functional diversity and miscellaneous subjects include more associations. However, agricultural chambers are present in every groups. Moreover, the results of the experiments are generally positive or neutral for genetic strategies, more variable and nuanced with a positive trend for agricultural practices and functional diversity, and overall positive for the miscellaneous subjects, in a negative climatic context. These overall positive results may partially reflect a communication bias, with a tendency to highlight successes. Nevertheless, they are also supported by literature for several levers.Additionally, a comparison with work conducted in other parts of the AgriAuRA2050 project revealed that the practices and levers tested by groups of farmers or individual farmers in the Auvergne-Rhône-Alpes region are similar with those studied in structured projects. Thus, the issues explored by research institutions and technical or professional organizations overlap with those of farmers.Les prédictions climatiques prévoient une hausse générale des températures et une intensification des sécheresses, notamment dans les zones méditerranéennes qui remontent en France vers le nord. Ainsi, à l’horizon 2050, le climat de la région Auvergne-Rhône-Alpes devrait devenir plus méditerranéen, et son agriculture devra faire face à de nouveaux défis météorologiques. Par ailleurs, du fait du système mondialisé dans lequel s’inscrit cette agriculture, ce n’est pas le seul défi auquel elle va se confronter, et une transition agroécologique est en marche pour répondre à ces enjeux alimentaires, sanitaires, environnementaux, économiques et sociaux, entre autres.Dans ce contexte, le projet AgriAuRA2050 vise à concevoir des modes et itinéraires de production envisageables pour permettre la pérennité des exploitations agricoles et garantir la viabilité économique de trois filières de la région Auvergne-Rhône-Alpes, grandes cultures, élevage d’herbivores et arboriculture, à l’horizon 2050 dans un contexte de changement climatique et de transition agroécologique. Dans le cadre d’un des volets de ce projet, un travail de synthèse des réponses connues des systèmes de cultures et d’élevages avec des itinéraires techniques non conventionnels sur la région a été réalisé par un inventaire de projets structurés mis en place sur la région Auvergne-Rhône-Alpes. L’objectif était de dégager les leviers étudiés par les projets réalisés en région sur l’adaptation de l’agriculture au changement climatique, notamment à la contrainte hydrique qui s’annonce comme un enjeu majeur dans les années à venir. Une caractérisation de ces leviers et une synthèse des résultats obtenus a aussi été réalisée.Les recherches effectuées essentiellement sur internet ont permis d’identifier 65 projets, et d’en dégager 27 leviers principaux qui ont été rassemblés en quatre grands groupes : génétique, pratiques agricoles, diversité fonctionnelle et sujets divers pour les projets plus prospectifs ne s’intéressant pas à des leviers à proprement parler. De nombreuses informations ont été collectées sur ces projets, notamment par des échanges avec les coordinateurs, afin de les caractériser au mieux. De plus, des résultats complets ou partiels ont pu être obtenus pour 31 projets, et ont fait l’objet d’une analyse qualitative synthétisant un effet global positif, négatif ou neutre de chaque essai selon le levier étudié et la variable mesurée.Les leviers étudiés ont pu être caractérisés par les filières les testant. Ainsi, les sujets divers sont les seuls à comprendre des projets s’intéressant à plusieurs filières, et ne comptent sinon que des projets sur l’élevage. Les trois filières se retrouvent dans les autres groupes de leviers, avec davantage de projets en grandes cultures pour ceux génétiques, davantage de projets en arboriculture pour ceux sur les pratiques agricoles, et plus d’équilibre pour les leviers de diversité fonctionnelle. Concernant les dates et durées de réalisation, les projets avec des leviers génétiques ou de pratiques agricoles sont plutôt courts, en cours et commencés après 2015, testés à une échelle réduite, majoritairement au site. En revanche pour les sujets divers, ils sont plutôt longs, surtout en cours également, et leur commencement s’étale entre 2000 et 2020. Ils sont aussi réalisés à une échelle plus large, en grande partie départementale ou régionale, tout comme les projets sur la diversité fonctionnelle, qui comptent par ailleurs la plus grande proportion de projets terminés, plutôt courts, et ayant plutôt commencés après 2015 avec cependant des projets plus anciens. Les structures portant les projets varient également entre les groupes. Ainsi, les structures plus tournées vers la recherche se retrouvent surtout dans les groupes pratiques agricoles et génétique, tandis que les groupes Diversité fonctionnelle et Sujets divers comptent plus d’associations. Les chambres d’agricultures se retrouvent en revanche dans chacun des groupes. Concernant les résultats des essais, ils sont plutôt positifs ou neutres pour les leviers de génétique, plus variables et nuancés avec une tendance positive pour ceux des pratiques agricoles et de la diversité fonctionnelle, et globalement positifs pour les sujets divers, en notant un contexte climatique négatif. Ces résultats globalement positifs peuvent en partie s’expliquer par un biais de communication, avec une tendance à mettre préférentiellement en avant les réussites. Néanmoins, ils sont aussi appuyés par de la bibliographie pour plusieurs leviers.De plus, un croisement avec des travaux effectués dans d’autres volets du projet agriAuRA2050 a permis de se rendre compte que les pratiques et leviers testées par des collectifs d’agriculteurs ou des agriculteurs isolés sur la région Auvergne-Rhône-Alpes rejoignent ceux auxquels les projets structurés s’intéressent. Ainsi, les problématiques explorées par la recherche et les instituts techniques ou professionnels croisent celles des agriculteurs
Correctly rounded vector implementation of the exponential function in binary64 arithmetic
No full textWe present a vectorized implementation of the exponential function that is correctly rounded in rounded-to-nearest binary64 floating-point arithmetic, demonstrating the feasibility of vectorized correctly rounded implementations. The vectorization is done automatically by the compiler
