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From technical advisory to innovation support services: Coexistence and transition of support models in the agricultural sector in Madagascar
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/612849/) * Autres projets (id;sigle;titre): ;SERVInnov;(EU) Strengthening Innovation Support SERVices to enhance INNOVations for sustainable food production//International audiencePurpose: The dual provision of technical advisory services and functional capacity development (FCD) services is not sufficient to support agricultural innovations, and needs to be enriched with other services. We explore the coexistence of support models implemented by organisations, in particular to what extent technical advisory services and FCD are combined with other innovation support services (ISS). Design/Methodology/Approach: Based on a pre-established typology, we conducted 115 semi-structured interviews with agricultural service providers in Madagascar. Qualitative content data analysis was used to characterise the set of ISS they provide. Findings: The results show that technical advisory services remain the most common type of ISS offered, while FCD is less common and is always combined with other ISS. We observed three support models implemented by organisations, depending on the type of organisation. Farmers' organisations, NGOs and R&D projects have progressed the farthest in the transition by diversifying their offer of ISS. Practical implications: We provide policy implications for the national Malagasy advisory strategy that will better account for the pluralism of organisations able to provide different kinds of advisory services and ISS. Theoretical implications: We identified three different support models used by organisations that reveal their strategy for supporting innovation. Originality/Value: We provide new insights into the pluralism of services offered and identify the organisations that have made the transition from providing 'classic' advisory services to providing innovation support services
Théorisation opéradique du produit Shuffle: structure d'algèbre de Hopf bicomplexe sur l'opérade associative unitaire
No full textThis work firstly extends the dot product developed in [3] by Batkam-Tcheka while giving a new non-commutative product called shuffle product which still provides to any pointed multiplicative operad, a bicomplex algebra structure. Secondly, a direct application of this results is developped on the unital associative operad A ss := n≥0 K[S n ] in order to construct a bicomplex Hopf algebra structure on this last one. Subsequently, we show that the underline Hopf algebra structure constructed on A ss is the same with the one defined on P er := n≥0 K[S n ] by Malvenuto-Reutenauer [[17]:section 3:page 977] or in the book of Cartier-Patras [[18]:proposition 9.7.1 and 9.7.4]. Furthermore, the bicomplex Hopf algebra structure obtained on A ss in our case extends the structure of Malvenuto-Reutenauer on Per and allows us to pass into (co)homology.Ce travail étend premièrement le dot produit développé par Batkam-Tcheka tout en donnant un nouveau un nouveau produit non commutatif appelé produit Shuffle. Ce nouveau produit munit aussi toute opérade multiplicative pointée d'une structure d'algebre bicomplexe
Du chaos à la transformation : une exploration des profonds bouleversements du changement dans les entreprises en Afrique
No full textDieser Artikel hat zum Ziel, die tiefgreifenden Umwälzungen des Wandels in afrikanischen Unternehmen zu untersuchen und dabei die wirtschaftlichen, politischen und sozialen Rahmenbedingungen hervorzuheben, in denen sie sich entwickeln. Die Studie befasst sich mit den Herausforderungen, denen afrikanische Unternehmen gegenüberstehen, und den Strategien, die sie verfolgen, um sich zu wandeln und erfolgreich zu sein. Die Studie zeigt, dass sich afrikanische Unternehmen zwar durch innovative Strategien, die Nutzung der Chancen der regionalen Integration und Globalisierung, Investitionen in Kompetenzen und Technologie sowie die Erfüllung der Erwartungen afrikanischer Verbraucher anpassen, jedoch durch regulatorische Beschränkungen, Korruption und politische Instabilität gebremst werden, die sich negativ auf ihren Wandel auswirken. Dieser Artikel trägt somit zum Verständnis der Transformationsdynamik von Unternehmen in Afrika und ihrer Auswirkungen auf politische Entscheidungsträger, Praktiker und Forscher im Bereich Organisationsmanagement bei.The aim of this article is to explore the profound upheavals of change in African companies, highlighting the economic, political and social contexts in which they operate. The study focuses on the challenges facing African companies and the strategies they are adopting to transform and prosper. The study shows that, although African companies are adapting by adopting innovative strategies, exploiting the opportunities offered by regional integration and globalization, investing in skills and technology, and responding to the expectations of African consumers, they are nonetheless hampered by regulatory constraints, corruption and political instability that have a negative impact on their transformation. This article thus contributes to understanding the dynamics of business transformation in Africa, and its implications for policy-makers, practitioners and researchers in organizational management.Cet article a pour objectif d'explorer les profonds bouleversements du changement dans les entreprises en Afrique, en mettant en évidence les contextes économique, politique et social dans lesquels elles évoluent. La problématique de l'étude porte sur les défis auxquels sont confrontées les entreprises africaines et les stratégies qu'elles adoptent pour se transformer et prospérer. L'étude montre que, bien que les entreprises africaines s'y adaptent en adoptant des stratégies innovantes, en exploitant les opportunités offertes par l'intégration régionale et la mondialisation, en investissant dans les compétences et la technologie, et en répondant aux attentes des consommateurs africains, elles sont néanmoins freinées par des contraintes réglementaires, la corruption et l'instabilité politique qui impactent négativement leur transformation. Cet article contribue ainsi à la compréhension des dynamiques de transformation des entreprises en Afrique, et de ses implications pour les décideurs politiques, les praticiens et les chercheurs en management des organisations
Transformation numérique et gestion universitaire dans les pays en développement : une revue de littérature et un cadre d'analyse pour le contexte malgache
No full textThis paper presents a literature review on digital transformation in university management, with a particular focus on developing countries and the Malagasy context. Through a thematic analysis of recent literature, four structuring dimensions are identified: digital transformation as an organizational process, university management practices, technology appropriation by stakeholders, and institutional digital governance. The analysis shows that existing literature, still largely rooted in Western contexts, gives little attention to African and Malagasy realities. We propose an analytical framework that articulates these four dimensions, designed for studying digital transformation in universities of developing countries. This framework will serve as the theoretical foundation for an ongoing doctoral research project conducted at the University of Mahajanga (Madagascar).Cet article propose une revue de littérature consacrée à la transformation numérique dans la gestion des universités, en portant une attention particulière aux pays en développement et au contexte malgache. L'analyse thématique de la littérature récente permet de dégager quatre dimensions structurantes : la transformation numérique entendue comme processus organisationnel, les pratiques de gestion universitaire, l'appropriation des technologies par les acteurs et la gouvernance numérique institutionnelle. Il en ressort que la littérature existante, encore très marquée par les contextes occidentaux, accorde peu de place aux réalités africaines et malgaches. Nous proposons un cadre d'analyse qui articule ces quatre dimensions et qui se veut adapté à l'étude de la transformation numérique dans les universités des pays en développement. Ce cadre servira de fondement théorique à une recherche doctorale en cours, menée à l'Université de Mahajanga (Madagascar).</div
Limits on the Carroll-Field-Jackiw electrodynamics from geomagnetic data
No full textInternational audienceLorentz-symmetry violation may be described via the CPT-odd, dimension-3, Carroll-Field-Jackiw term, which couples the electromagnetic fields to a constant 4-vector selecting a preferred direction in spacetime. We solve the field equations using the Green's method for a static point-like magnetic dipole and find the -dependent corrections to the standard dipolar magnetic field that strongly dominates the near-Earth magnetic field. Given the very good agreement between current models and ground- and satellite-based geomagnetic data, our strongest constraints on the components of in the Sun-centered frame read for at the two-sigma level. This represents an improvement of about four orders of magnitude over earlier bounds based on other geophysical phenomena
Natural variation in Arabidopsis uncouples leaf and flower development and reveals massive transcriptomic heterochrony
No full textInternational audiencePlant development is a sequence of precisely timed and spatially coordinated events that produce organs such as leaves and flowers. In Arabidopsis thaliana, for example, the development of leaves (called bracts in the inflorescence) halts once the first flower forms. Understanding how this transition is regulated is key for decoding how developmental programmes are coordinated during the floral transition. In this study, we investigated a natural phenotypic variation that uncouples bract repression from flower initiation. We discovered that the continued formation of bracts after the floral transition involves complex genetic interactions across at least four loci. Interestingly, none of these loci included known floral identity genes previously linked to bract repression, pointing to novel regulators in the coordination of bract and flower development. Using time-series transcriptomics and curve registration, we found that differences in gene expression levels when bracts persist are mainly driven by a massive desynchronization of gene dynamics. This affects a wide range of biological processes beyond those associated with leaf identity. These findings align with the ‘inverse hourglass’ model, which proposes that transcriptomic divergence at transitional stages contributes to morphological variation. Our results suggest that this model may also explain trait variability within species, highlighting how transcriptome dynamics shape phenotypic robustness during developmental transitions
Gains visibles, pertes invisibles : une approche formelle dupiège de la séduction et de l'accumulation des tombes sociales
No full textAttractive stochastic systems often generate visible gains while accumulatinglatent structural costs. This paper introduces a rigorous spectral framework for quantifyingsuch hidden-cost dynamics within absorbing Markov models.We define the Hidden Graveyard Cost (HGC) as the expected cumulative hidden exposureprior to absorption and express it in closed form through the resolvent operator (I −Q)−1 ofthe transient subsystem. We establish that hidden-cost finiteness is equivalent to the spectralcondition ρ(Q) Les systèmes stochastiques attractifs génèrent souvent des gains visibles tout en accumulant des coûts structurels latents. Cet article présente un cadre spectral rigoureux permettant de quantifier cette dynamique des coûts cachés dans le cadre des modèles markoviens absorbants.Nous définissons le coût caché du cimetière (HGC) comme l'exposition cachée cumulative attendue avant absorption et l'exprimons sous forme fermée à travers l'opérateur résolvent (I -Q) -1 du sous-système transitoire. Nous établissons que la finitude des coûts cachés est équivalente à la condition spectrale ρ(Q) < 1, et nous prouvons la divergence hyperbolique HGC ∼ (1 -ρ(Q)) -1 lorsque le rayon spectral tend vers l'unité. L'analyse de sensibilité révèle une amplification quadratique près de la criticité, tandis que la variance explose à l'ordre cubique, conduisant à l'instabilité et à l' imprévisibilité.Une décomposition spectrale générale montre que tout comportement asymptotique est régi par le mode propre dominant de Perron-Frobenius. Nous développons ensuite un cadre de bifurcation critique et validons les prédictions théoriques par des simulations numériques.Les résultats démontrent que la fragilité systémique dans les systèmes attractifs est codée spectralement : la résilience est déterminée par la distance à la frontière spectrale.</div
Cuba et la lutte pour l’indépendance de l’Algérie, 1959-1962
No full textInternational audienceThis article examines Cuba’s involvement on the side of the Algerian National Liberation Front between 1959 and 1962, from its stance at the United Nations to the material and military assistance provided to the Provisional Government of the Algerian Republic (GPRA). Drawing on French and U.S. diplomatic archives, UN debates, and Cuban and Algerian sources, it argues that Havana went far beyond rhetorical support and turned the Algerian struggle into an early testing ground for its state-led internationalism. The shift from Batista’s pro-French alignment to Fidel Castro’s open backing of Algerian self-determination, the recognition of the GPRA, consistent pro-independence voting at the UN, and the dispatch of arms and wounded fighters reveal a principled choice, maintained despite U.S. pressure and the risk of damaging relations with Paris. The study highlights the diplomatic shock this reversal produced in France, as well as the way in which Algerian-Cuban convergence came to embody, in Washington’s eyes, the threat of an emerging anti-colonial and anti-imperialist front within the Third World.Este artículo analiza el compromiso de Cuba junto al Frente de Liberación Nacional argelino entre 1959 y 1962, desde las tribunas de las Naciones Unidas hasta la ayuda material y militar brindada al Gobierno Provisional de la República Argelina. A partir de archivos diplomáticos franceses y estadounidenses, de los debates en la ONU, de la prensa y de fuentes cubanas y argelinas, muestra que La Habana no se limita a un apoyo retórico, sino que convierte la causa argelina en una prioridad de su internacionalismo de Estado. La ruptura con el alineamiento profrancés del régimen de Batista, el reconocimiento del GPRA, el voto sistemático a favor de la autodeterminación y el envío de armas y combatientes dan cuenta de una elección de principios, asumida pese a las presiones de Washington y al riesgo de deteriorar las relaciones con París. El estudio pone de relieve el trauma diplomático provocado en Francia por este giro, así como la manera en que la convergencia argelino-cubana encarna, a los ojos de Estados Unidos, la amenaza de un frente anticolonial y antiimperialista en el seno del Tercer Mundo.Cet article analyse l’engagement de Cuba aux côtés du Front de Libération Nationale algérien entre 1959 et 1962, depuis les tribunes des Nations unies jusqu’à l’aide matérielle et militaire apportée au Gouvernement Provisoire de la République Algérienne (GPRA). À partir des archives diplomatiques françaises et étasuniennes, des débats onusiens, de la presse et des sources cubaines et algériennes, il montre que La Havane ne se contente pas d’un soutien rhétorique, mais fait de la cause algérienne une priorité de son internationalisme d’État. La rupture avec l’alignement pro-français du régime Batista, la reconnaissance du GPRA, le vote systématique en faveur de l’autodétermination et l’envoi d’armes et de combattants témoignent d’un choix de principe, assumé malgré les pressions de Washington et le risque de détériorer les relations avec Paris. L’étude met en lumière le traumatisme diplomatique provoqué en France par ce basculement, ainsi que la façon dont la convergence algéro-cubaine incarne, aux yeux des États-Unis, la menace d’un front anticolonial et anti-impérialiste au sein du Tiers-monde
Volcanic plume height during the 2021 Tajogaite eruption (La Palma) from two complementary monitoring methods – implications for satellite-based products
No full textInternational audienceAbstract. Volcanic emissions from the Tajogaite volcano, located on the Cumbre Vieja edifice on the island of La Palma (Canary Islands, Spain), caused significant public health and aviation disruptions throughout the eruption (19 September–13 December 2021, officially declared over on 25 December). Nonetheless, it is considered the most significant volcanic event in Europe over the past 75 years due to the substantial amount of SO2 released into the atmosphere. The Instituto Geográfico Nacional (IGN), the authority responsible for volcano surveillance in Spain, implemented extensive operational monitoring to track volcanic activity and to provide a robust estimation of the volcanic plume height using a video-surveillance network. In parallel, the State Meteorological Agency of Spain (AEMET), in partnership with other Spanish ACTRIS (Aerosol, Clouds, and Trace Gases Research Infrastructure) members and collaborating institutions, conducted an unprecedented instrumental deployment to evaluate the impacts of this volcanic event on atmospheric composition. This effort included a network of aerosol profilers surrounding the volcano. A total of four profiling instruments were installed on La Palma: one MPL-4B lidar and three ceilometers. Additionally, a pre-existing Raman lidar on the island contributed valuable data to this study. These efforts are undertaken due to the importance of monitoring volcanic plume height in terms of air quality (necessary for the implementation of effective civil protection policies), volcanic activity surveillance (for tracking and forecasting eruptive behaviour), and, from a scientific perspective, for improving our understanding of the climatic and radiative impacts of this type of aerosol. In this study, the eruptive process was characterised in terms of the altitude of the dispersive volcanic plume (hd), measured by both IGN and AEMET-ACTRIS, and the altitude of the eruptive column (hec), measured by IGN. Modulating factors such as seismicity and meteorological conditions were also analysed. The consistency between the two independent and complementary datasets (hd,IGN and hd,AEMET) was assessed throughout the eruption (mean difference of 258.6 m). Our results confirmed the existence of three distinct eruptive phases, encompassing a range of styles from Strombolian explosive to effusive activity. While these phases have been characterised in previous studies, the results of the present work provide complementary information and novel insights from an alternative observational approach, which may be of use in future volcanic crises and will be applied to operational surveillance during such events. A subsequent comparison of hd,AEMET with the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) aerosol layer height product (ALHCALIOP) revealed a systematic underestimation by the satellite product, with a mean difference of 392.2 m. Finally, the impact of using hec in estimating SO2 emissions from the NASA MSVOLSO2L4 satellite-based product was evaluated. When a fixed (standard) plume altitude of 8 km was used instead of the observed hec, the total SO2 emission was significantly underestimated by an average of 56.2 %, and by up to 84.7 %. These findings underscore the importance of accurately determining the volcanic plume height when deriving SO2 emissions from satellite data