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Worker Cooperatives in the Light of Convention Theory
No full textInternational audienceThis chapter explores the relevance of the economics and sociology of conventions (EC/SC or convention theory) as a theoretical framework to study cooperatives. Three main arguments are developed. First, cooperative institutional characteristics make them more transparent, egalitarian, and reflexive than capitalist firms which is likely to produce more situation of disputes and uncertainty that can be analyzed through EC/SC. Second, the economies of worth framework allows authors to explore the microfoundations of individual and organizational responses to institutional pluralism. To demonstrate this point, empirical articles on cooperatives are reviewed, and comparisons and perspectives for future researches are suggested. Third, EC/SC brings light to one of the crucial questions in the literature on cooperatives: their level of autonomy from capitalist institutions. To address this question, the empirical literature on cooperatives uses EC/SC in an effort to characterize the conditions under which some cooperatives can develop autonomy and criticism of the capitalist institutions
New remains of Mosasauroidea (Reptilia, Squamata) from the Upper Cretaceous (Santonian) of Aude, southern France
No full textInternational audienceNew mosasaurid remains (Squamata) were collected from various Santonian localities in the Sougraigne area (Aude Department, southern France). Cranial bones, some vertebrae, two scapulae and a phalanx are assigned to the plioplatecarpine Platecarpus cf. tympaniticus, while pelvic bones, two vertebrae and a femur (?) are referred to Tylosaurus sp. Tooth marks made by sharks, teleosts or mosasaurids are observed on the mosasaurid vertebrae. These Santonian (86.3–83.6 Ma) Platecarpus occurrences, known since almost one century, are the oldest from Europe. This deposit also yielded some elasmobranch teeth, belonging to taxa such as Squalicorax kaupi, Cretoxyrhina mantelli, Cretolamna sp. and Polyacrodus brabanticus. A review of plioplatecarpine palaeobiogeographical distribution through Late Cretaceous suggests that it follows that of other mosasaurid clades, reaching a worldwide distribution by Maastrichtian time, probably favored by marine routes largely opened at this time
Recomposer les territoires pour les adapter aux effets de la crise climatique : l’après-catastrophe comme opportunité pour une meilleure habitabilité ?
No full textInternational audienceThe period following a disaster is considered by some as a window of opportunity to rethink the planning of vulnerable territories. In a context of climate crisis, this could be an opportunity to change the way we think about planning, with risks, environments and their dynamics? And thus work to make these areas more habitable? I will try to answer this question through the study of the process of urban recomposition chosen by two municipalities in the Aude department following the flood of October 2018. The local actors did not favour identical reconstruction, but rather the will to rethink the organisation of the territory to make it more resilient in the face of crises and more pleasant to live in on a daily basis. The result of collective dynamics, the recomposition of these two territories is part of a logic of adaptation and resilience, embodying, in some respects, a new way of considering development in the Anthropocene era.Después de una catástrofe es habitual que algunas personas consideren esta situación como una oportunidad para replantearse la planificación de las zonas vulnerables. En el contexto de la crisis climática, ¿no es esta una ocasión para cambiar nuestra forma de entender la planificación, en relación con los riesgos, los entornos y sus dinámicas? ¿Y cómo podemos hacer que estas zonas sean más habitables? Este artículo tiene por objectivo responder a estas preguntas a partir del análisis del proceso de reordenación urbana llevado a cabo por dos municipios del departamento de Aude tras las inundaciones de octubre de 2018. Como ocurre a menudo, los actores locales no optaron por una reconstrucción idéntica, sino por repensar la organización de la zona para hacerla más resiliente frente a las crisis y más confortable para la vida diaria. Como resultado de una dinámica colectiva, la reorganización de estas dos zonas se inscribe en una lógica de adaptación y resiliencia, encarnando, en algunos aspectos, una nueva forma de entender la planificación en la era del Antropoceno.La période qui s’ouvre après une catastrophe est considérée par certains comme une fenêtre d’opportunité pour repenser l’aménagement des territoires vulnérables. Dans un contexte de crise climatique, n’est-ce pas l’occasion de changer la manière de penser l’aménagement, avec les risques, les milieux et leurs dynamiques ? Et ainsi d’œuvrer à une meilleure habitabilité de ces territoires ? Nous nous efforçons de répondre à ce questionnement à travers l’étude du processus de recomposition urbaine engagé par deux communes du département de l’Aude suite à l’inondation d’octobre 2018. Ce n’est pas comme souvent la reconstruction à l’identique qui a été privilégiée par les acteurs locaux, mais au contraire la volonté de repenser l’organisation du territoire pour le rendre plus résilient face aux crises et plus agréable à vivre au quotidien. Fruit d’une dynamique collective, la recomposition de ces deux territoires s’inscrit dans une logique d’adaptation et de résilience incarnant ainsi, à certains égards, une nouvelle manière d’envisager l’aménagement à l’heure de l’Anthropocène
Assessing the Performance Profiles of Microfinance Institutions: New Insights into the Management of their Double Bottom-Line
No full textInternational audienceMicrofinance institutions (MFIs) deal with a double bottom-line and often strive to maintain a balance. This paper investigates a network of MFIs that serves poor populations in rural Cameroon, and explores the link between MFI performance and the network structure, by means of the contingency and fit theories and the Data Envelopment Analysis (DEA) approach.By looking at the organizational design of the network and the double bottom-line management issue of its MFIs, results show that the most performing efficient MFIs require less control from the network management team and are important contributors to the exploration of new solutions and services, while dealing with a trade-off regarding their social activity. On the contrary, MFIs that have recently launched their activity and need more supervision from network managers greatly benefit from the exploitation of knowledge available within the network, while dealing with a trade-off as regards their financial activity. Between those two extremes, MFIs are deploying their activity with a balanced double bottom-line. Transitory imbalances can therefore be considered as opportunities for exploration, by sustaining performance and fostering growth within the network, thus opening new insights into how observed trade-offs between the financial and social activities of MFIs should be considered.</p
Fire drives major Holocene vegetation shifts between subtropical and Mediterranean‐type ecosystems: a case study from a biodiversity hotspot in South Africa
No full textInternational audienceFire plays a pivotal role in driving ecological shifts between Mediterranean‐type vegetation and subtropical ecosystems in South Africa . This study investigates long‐term environmental dynamics and ecological regime changes at the Mediterranean‐type vegetation /subtropical boundary using a 6000‐year palaeoecological sequence from the Baviaanskloof – a region of South Africa characterized by high levels of biodiversity and climate dynamism. Combining fossil pollen and microcharcoal data from a rock hyrax Procavia capensis midden, we analyse vegetation responses to environmental changes. Our findings reveal that Mediterranean‐type vegetation resilience prevailed until ca 2800 cal year BP when a major fire event triggered a transition to a subtropical thicket‐dominated environment. This abrupt ecological turnover underscores the significance of fire as a major driver of vegetation change at the Mediterranean‐type vegetation /subtropical boundary. Our study emphasizes the vulnerability of Mediterranean‐type vegetation ecosystems to global environmental change, suggesting potential implications for similar biome boundaries worldwide. By integrating multi‐proxy palaeoecological evidence, we gain insights into the resilience and vulnerability of these ecosystems, aiding in understanding future responses to climate change scenarios
Cryptosporidium parvum et microbiote intestinal : une piste de recherche de nouvelles thérapies alternatives.
No full textInternational audienceLa cryptosporidiose est zoonose à l’origine de diarrhées chez l’Homme et chez l’animal notamment les jeunes ruminants. Elle est provoquée par des protozoaires à apicomplexe intracellulaires mais extracytoplasmiques dépendants de la cellule parasitée pour leur métabolisme, isolés des voies de délivrance de molécules actives et de la réponse immunitaire de l’hôte, et très résistants dans l’environnement. Il n’existe pas présentement de thérapies complètement efficaces disponibles aussi bien chez l’homme que chez l’animal. En étant impliquée dans la prévention et le traitement des diarrhées néonatales à Cryptosporidium chez les jeunes ruminants, la médecine vétérinaire joue un rôle crucial dans la limitation de la contamination environnementale par les oocystes parasitaires.Le microbiote intestinal est impliqué dans de nombreuses fonctions de l’organisme, car certaines molécules produites dans l’intestin passent dans la circulation sanguine et peuvent atteindre tous les organes y compris le cerveau. Le microbiote intestinal joue un rôle fondamental dans la digestion. Il dégrade les aliments complexes que l’organisme est incapable de digérer seul. Un autre rôle majeur est de protéger l’organisme des différents pathogènes en réagissant avec le système immunitaire.La perturbation du microbiote intestinal par Cryptosporidium a été rapportée chez des souris adultes immunodéprimées, mais aucune étude n’a été faite ni sur les souriceaux ni sur les chevreaux.L'objectif de cette étude est d'évaluer l'efficacité de la levure vivante Saccharomyces cerevisiae (Sc 5 et Sc 3-A) pour prévenir la cryptosporidiose expérimentale chez les chevreaux nouveau-nés infectés expérimentalement par la souche Iowa de Cryptosporidium parvum. Quarante chevreaux mâles âgés de 1 jour (race Alpine) ont été répartis en 4 groupes : 1) le groupe témoin non infecté 2) le groupe témoin infecté 3) le groupe infecté supplémenté avec Sc 3-A 4) le groupe infecté supplémenté avec Sc 5. Cette supplémentation a été effectuée quotidiennement pendant 26 jours. Les groupes infectés ont été inoculés par voie orale avec 106 oocystes de la souche Iowa de C. parvum. La supplémentation en levures vivantes a permis d'améliorer l'hydratation des animaux, de réduire l'intensité et la durée de la diarrhée et de l'infection. La supplémentation en Sc 5 a été plus efficace que la supplémentation en Sc 3-A pour maintenir la température des animaux dans une fourchette physiologique, pour améliorer le gain de poids quotidien et l'état général des animaux (score de santé et score de déshydratation). La supplémentation par les deux levures n'a pas retardé l'apparition de la diarrhée. L'examen histologique effectué 6 jours après l'infection a révélé des stades parasitaires et des changements microscopiques principalement limités à l'iléon. La supplémentation alimentaire en levuresvivantes (Sc 5) module de manière bénéfique le profil du microbiote intestinal, directement ou indirectement, de telle sorte que la prolifération de C. parvum est défavorable pendant la période néonatale. Ces résultats indiquent que la supplémentation alimentaire en levures vivantes, principalement par Sc 5, réussit à prévenir la diarrhée et à restaurer la dysbiose. Par conséquent, l'utilisation d'une supplémentation en levures vivantes dans l'alimentation des ruminants pourrait être une méthode alternative intéressante pour lutter contre cette parasitose
An Update on the Waste Management of the Amazonian Açaí Berry for the Civil Engineering Sector
No full textInternational audienceThe rising demand for açaí berries in Amazonian Brazil and French Guiana generates a significant amount of waste, namely the fruit’s stone, which accounts for 80% of the dry fruit’s mass. Recently, various studies have explored the potential valorization of açaí waste in the civil engineering sector, including the functionalization of the fibers surrounding the stone and the multiphysics testing of composite materials based on açaí fibers and/or stones, treated or untreated. This literature review aims to provide an overview of the technology readiness levels (TRLs) of the existing techniques capable of reducing the environmental impact of both the cultivation and management of naturally occurring açaí. While the research to date is promising, it remains at the prototype stage, and the mass ratio of waste in composites, regardless of their type, limits addressing the underlying ecological problem of açaí waste processing. Further experimental investigations are required to improve the functionalization processes, enabling the use of higher proportions of fibers and/or stones in cementitious composites and their large-scale production
Intensifier les fonctions écologiques des sols pour une agriculture durable : agir avec les acteurs
No full textFull-flock-full-pregnancy monitoring of liveweight progression in Romane meat ewes, using a walkover-weighing system in rangelands
No full textSession 65. PLF for health, behaviour and welfareInternational audienceLittle is known about liveweight (LW) dynamics of females during pregnancy, which is more critical under rangeland conditions. In this work, we implemented fine monitoring (daily) of the LW progress of each Romane ewe belonging to the La Fage flock, throughout the whole pregnancy, and with the help of our walk-over-weighing (WoW) platform. The trial involved 279 ewes (77 primiparous and 202 multiparous) which initial average age (and LW, kg ±SEM) were 1.5 (56.5±1.98) and 4 years, 3 months old (79.3±1.15), respectively. A period of adaptation (around 2 weeks) was necessary to voluntary cross the WoW (achieved by 80% of ewes). Raw dataset outliers were automatically filtered by our free web app ORIOLE (https://oriole.sk8.inrae.fr/). The final, clean dataset was contrasted with other relevant individual information available e.g. pregnancy diagnosis at mid-pregnancy (~72± 8 d), number of fetus, litter size, sex and LW at lambing. Constant ewes’ LW progress was easily followed by the WoW, making possible to detect anomalies e.g. abortions or individual presence/absence at a given precise date. The infrastructure is ideal for making further deep interpretations such as fetus growth rate in function of litter size, lamb’ sex, the relationship with LW at lambing etc. Also, for contributing to the development of early warning systems helping to decision makings during such a critical physiological stage in the farm and beyond. This work was in the scope of the H2020 TechCare project (GA 862050)
Eddy covariance measurements reveal a decreased carbon sequestration strength 2010–2022 in an African semiarid savanna
No full textInternational audienceMonitoring the changes of ecosystem functioning is pivotal for understanding the global carbon cycle. Despite its size and contribution to the global carbon cycle, Africa is largely understudied in regard to ongoing changes of its ecosystem functioning and their responses to climate change. One of the reasons is the lack of long‐term in situ data. Here, we use eddy covariance to quantify the net ecosystem exchange (NEE) and its components—gross primary production (GPP) and ecosystem respiration ( R eco ) for years 2010–2022 for a Sahelian semiarid savanna to study trends in the fluxes. Significant negative trends were found for NEE (12.7 ± 2.8 g C m 2 year −1 ), GPP (39.6 ± 7.9 g C m 2 year −1 ), and R eco (32.2 ± 8.9 g C m 2 year −1 ). We found that NEE decreased by 60% over the study period, and this decrease was mainly caused by stronger negative trends in rainy season GPP than in R eco . Additionally, we observed strong increasing trends in vapor pressure deficit, but no trends in rainfall or soil water content. Thus, a proposed explanation for the decrease in carbon sink strength is increasing atmospheric dryness. The warming climate in the Sahel, coupled with increasing evaporative demand, may thus lead to decreased GPP levels across this biome, and lowering its CO 2 sequestration