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3D dissections and DiceCT methods: you say you want a revolution, well you know...
No full textInternational audienceMany studies have been devoted to describing the morphological variations of the rodent skull and teeth. In comparison, the associated musculature has received relatively little attention. To date, myological studies have focused on only a limited number of rodent species, and detailed descriptions of the masticatory apparatus have covered only a small portion of the current rodent diversity. For instance, our knowledge of the muscular interspecific variation in murid rodents appears to be rather limited, with only a handful of taxa described out of the 834 recognized species. Different terminologies have been used depending on the group studied, which has largely hindered the recognition of homologies across the entire order. Advances in technology are driving a great deal of research, particularly in the areas of imaging and functional simulation. High-resolution X-ray microtomography has proven to be a powerful tool for unravelling intricate anatomical details, and much progress has recently been made in describing the mammalian masticatory apparatus using diffusible iodine-based contrast-enhanced computed tomography (DiceCT). Yet, despite the widespread use of imaging technology and shape analyses to study mineralized tissues (bones and teeth), soft tissues are much less commonly studied. We used DiceCT methods to explore the morphological variation of the musculature and biomechanics across the entire order Rodentia, and compared these results with observations made by classical dissections. Although DiceCT methods have allowed us to characterize the intricacy of the muscular and nervous systems, we have shown that some aspects of the morphological complexity of the masticatory apparatus may be either overlooked or missed. We advocate the combined use of traditional and 3D dissections to fully capture the extent of anatomical variation, since the use of DiceCT methods alone may create new confusion rather than help resolve old controversies
Semi-automated muscle fiber modeling from iodine-stained μCT scans: potential and pitfalls
No full textInternational audienceDetailed morpho-functional analysis requires quantification of both hard and soft tissues. Muscular traits (volume, weight, fiber length and angles) are particularly important because they determine mobility. Muscle dissections and chemical treatment have been and are still being used to quantify these traits, in particular to calculate muscle PCSA and force. At the same time, technical advances in μCT scanning now enable to access the same traits less destructively and in 3D. Recently published algorithms, such as the one included in the R package GoodFibes, aim to automatically trace and model muscle fibers or fascicles, allowing to display them graphically, but also to extract lengths and angles. Here we present a semi-automatic pipeline combining Fiji/ImageJ scripts and the GoodFibes package to extract muscle fibers in 3D reconstructions of six species of nesomyid rodents. We compare the results of this pipeline to those obtained by dissection and dissolution of muscles in the same specimens. Although the pipeline allows for the rapid acquisition of larger amounts of data than dissection, the paired results obtained by the two methods are quite different from each other in some specimens. Factors that appear to play a role in explaining large discrepancies are: 1) the orientation of the 3D reconstruction slices relative to that of the muscle fascicles; 2) the delimitation between fascicles, which is affected by staining, contrast and scan definition; 3) the anatomy, especially when the orientation of fascicles varies within a given muscle. These pitfalls mean that users should not take the output of GoodFibes at face value, but fortunately they are fairly easy for users to detect thanks to the visualization capabilities of the package in association with other software
The importance of understanding the multiple dimensions of power in stakeholder participation for effective biodiversity conservation
No full textInternational audienceBiodiversity conservation are increasingly focused on involving stakeholder engagement, making power a key concept in understanding its success and failure. Power is often conceptualized as unidimensional and coercive, but a multidimensional view better reflects structural power, as well as its productive and enabling potential. This paper investigates how different dimensions of power in participatory processes affect biodiversity conservation objectives. Six case studies from Europe and Asia‐Pacific were analysed using an adapted framework that explores the interlinkages between ‘ power over ’ and ‘ transformative power ’, looking at the scale and space in which power occurs, and analysing in which arenas of power and under which form of expression it appears. The framework distinguishes between the different ways to exert influence (‘power to’, ‘power with’, ‘power within’, ‘power for’), as well as the dynamics of domination and resistance observed in decision‐making (visible power), hidden biases and exclusionary experiences (hidden power), and actions that either reinforce or resist social norms and beliefs (invisible and systematic power). Focusing on biodiversity, the different arenas of power allow us to go deeper than the surface issues and conflicting interests of diverse participants, regarding for example wildlife, to question underlying power dynamics. Different expressions of power, more specifically the ‘power for’ dimension, allow an understanding of how participants integrate nature and biodiversity in their aspirations. The different levels of power also highlight the need to focus not only on the local level but to analyse how participatory processes are embedded in national, or even international governance in a globalized world. Finally, they shed light on two challenges in participatory processes regarding biodiversity: the representation of non‐human interests (designated here as ‘beyond‐human’ voices), and the integration of multiple forms of knowledge systems. Synthesis and applications : Integrating power into biodiversity issues involves deconstructing normalized discourses that focus solely on certain more powerful human agents, their interests and scientific knowledge, and creating new narratives, knowledge and embodied practice of learning and action to encompass a wider diversity of voices and views. Read the free Plain Language Summary for this article on the Journal blog.La conservation de la biodiversité implique de plus en plus l'engagement des parties prenantes, faisant du pouvoir un concept clé pour comprendre son succès et son échec. Si le pouvoir est souvent conceptualisé comme unidimensionnel et coercitif, une vision multidimensionnelle reflète mieux le niveau structurel auquel il peut s'exprimer et donne la possibilité d'explorer son potentiel productif et facilitateur. Cet article étudie comment les différentes dimensions du pouvoir dans les processus participatifs affectent les objectifs de conservation de la biodiversité. Six études de cas situées en Europe et Asie‐Pacifique ont été analysées à l'aide d'un cadre théorique adapté qui explore les liens entre le “pouvoir sur” et le “pouvoir transformateur”, en examinant à à quelle échelle et dans quel espace le pouvoir se manifeste, dans quelles arènes (visible, caché, invisible et systématique) et sous quelle forme il s'exprime (‘pouvoir de’, ‘pouvoir avec’, ‘pouvoir intérieur’, ‘pouvoir pour’). Les différentes arènes du pouvoir nous permettent d'analyser plus en profondeur les problèmes liés à la conservation de la biodiversité et les intérêts conflictuels des divers participants pour remettre en question les dynamiques de pouvoir sous‐jacentes. Les différentes expressions du pouvoir, et plus particulièrement la dimension du “pouvoir pour”, permettent de comprendre comment les participants intègrent la nature et la biodiversité dans leurs aspirations. Les différents niveaux de pouvoir soulignent également la nécessité de ne pas se concentrer uniquement sur le niveau local, mais d'analyser la manière dont les processus participatifs sont intégrés dans des processus de gouvernance au niveau national voire international dans un monde toujours plus globalisé. Enfin, ils mettent en lumière deux défis auxquels les processus participatifs de conservation de la biodiversité doivent faire face: la représentation des non humains et l'intégration de multiples formes de savoirs. Intégrer le pouvoir dans les questions relatives à la conservation de la biodiversité implique de déconstruire les discours normalisés qui se concentrent uniquement sur la puissance de certains acteurs, leurs intérêts et leurs savoirs scientifiques. Au lieu de cela, nous devons développer de nouveaux récits, connaissances, façons d'apprendre et d'agir qui incluent un plus large éventail de voix et de perspectives
Poster de présentation du living lab LLUNAM- Réseau de living labs Solu-Biod
No full textInternational audienc
Point d’étape sur les expérimentations archéologiques d’ensilage en Roussillon
No full textInternational audienceEn 2018, dans le cadre d’une conférence à l’AAPO, Cécile Dominguez présentait les expérimentations archéologiques d’ensilage menées dans notre département et les premiers résultats encourageants obtenus après deux ans. Les années ont passé et nos questionnements ont nécessairement évolué au fur et à mesure des cycles de conservation successifs. Au travers de résultats significatifs, ce point d’étape propose ici à la fois de rappeler le contexte, la méthodologie et d’illustrer les principaux gestes
Développement de pâtes alimentaires à base de matières premières sans gluten adaptées aux changements climatiques couvrant les besoins nutritionnels des populations et appauvris en facteurs antinutritionnels
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Bayesian modeling of post-vaccination serological data suggests that yearly vaccination of dog aged <2 years old is efficient to stop rabies circulation in Cambodia
No full textInternational audienceRabies control remains challenging in low and middle-income countries, mostly due to lack of financial resources, rapid turnover of dog populations and poor accessibility to dogs. Rabies is endemic in Cambodia, where no national rabies vaccination program is implemented. The objective of this study was to assess the short and long-term vaccination-induced immunity in Cambodian dogs under field conditions, and to propose optimized vaccination strategies. A cohort of 351 dogs was followed at regular time points following primary vaccination only (PV) or PV plus single booster (BV). Fluorescent antibody virus neutralization test (FAVNT) was implemented to determine the neutralizing antibody titer against rabies and an individual titer ≥0·5 IU/mL indicated protection. Bayesian modeling was used to evaluate the individual duration of protection against rabies and the efficacy of two different vaccination strategies. Overall, 61% of dogs had a protective immunity one year after PV. In dogs receiving a BV, this protective immunity remained for up to one year after the BV in 95% of dogs. According to the best Bayesian model, a PV conferred a protective immunity in 82% of dogs (95% CI: 75–91%) for a mean duration of 4.7 years, and BV induced a lifelong protective immunity. Annual PV of dogs less than one year old and systematic BV solely of dogs vaccinated the year before would allow to achieve the 70% World Health Organization recommended threshold to control rabies circulation in a dog population in three to five years of implementation depending on dog population dynamics. This vaccination strategy would save up to about a third of vaccine doses, reducing cost and time efforts of mass dog vaccination campaigns. These results can contribute to optimize rabies control measures in Cambodia moving towards the global goal of ending human death from dog-mediated rabies by 2030
