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Direct proton transfer on Ar supports the presence of a charge density bubble linked to a novel nuclear structure below Ca
No full textInternational audienceThe Ar(He,d)K reaction was performed in inverse kinematics using a radioactive Ar beam produced by the SPIRAL1 facility at GANIL and a cryogenic He target. The AGATA-MUGAST-VAMOS setup allowed the coincident measurement of the rays, deuterons and recoiling K isotopes produced by the reaction. The relative cross sections towards the proton-addition states in K point towards a depletion of the shell. The experimental findings are in good agreement with ab initio calculations, which predict that Ar exhibits a charge density bubble associated with a pronounced proton closed-shell character
Behavioural adaptability of wild geladas (Theropithecus gelada) in human-impacted areas revealed by encounters with free-roaming dogs and potential threats
No full textInternational audienceStudying interactions between domestic species and wild primates is crucial for understanding the impacts of human expansion on wildlife. While free-roaming domestic dogs are one of the most common human-introduced carnivores and pose potential threats to primates, their direct influence on primate behaviour remains largely overlooked. Geladas (Theropithecus gelada), a primate species endemic to Ethiopia's Afro-alpine grasslands with a specialized diet, are facing challenges from habitat loss and interactions with domestic animals throughout their geographical range. Here, we followed 17 gelada group units in an unprotected area of Ethiopia (6-month period, 598 h of observation) and explored their behavioural responses to different natural and human-related threats. We observed strong vigilance in response to the presence of humans chasing nearby groups, as well as in response to dogs and eagles. Other raptors and birds of prey (including vultures and kites) produced no vigilance response, or only a modest one (e.g., augur buzzard). We also report encounters and interactions (n = 16) between dogs and geladas. Although we observed some behaviours associated with agonism and anxiety from both sides, the presence of dogs at close proximity was mainly tolerated. This contrasts with data from populations inhabiting protected areas where geladas typically exhibit flight responses to encounters with dogs. These differences between populations hint at gelada behavioural plasticity to adapt and live in human-impacted environments with limited alternative feeding sites. Increased awareness and documentation of dog-primate interactive events are essential to better grasp the broader implications of human-wildlife coexistence, one of the most important challenges of the Anthropocene
La propriété du sol n’exclut (toujours) pas la qualification de chemin d’exploitation
No full textInternational audienceLa Cour de cassation rappelle deux principes fermement établis en matière de droit rural. Le premier est qu’un chemin peut recevoir la qualification de « chemin d’exploitation » même s’il est entièrement situé sur la parcelle d’un propriétaire. Le second est que les riverains disposent alors d’un droit d’usage auquel le propriétaire ne doit pas porter atteinte
Caractérisation ultrasonοre de suspensions solides dans un fluide visqueux
No full textUltrasonic methods are widely used in various fields for the evaluation and characterization of multiphase media. Ultrasound is applied in the diagnosis of various products, including polluted fluids (wastewater treatment), food products (characterization of lipids and proteins), and suspended sediments (evaluation of concentration and particle size distribution).This research aims to establish a relationship between ultrasonic signals and particle concentration, based on the nature, shape, and distribution of the particles.To this end, an experimental setup was developed and implemented, and numerical models of multiple scattering were processed and validated. Ultrasonic measurements were carried out to characterize suspensions under dynamic flow, using specific instrumentation designed to measure effective ultrasonic properties such as attenuation and velocity.The signals were acquired and averaged under steady-state conditions using Python; signal post-processing was carried out in the spectral domain using FFT on the relevant echoes; the useful ultrasonic properties were deduced as a function of frequency via attenuation and velocity.Experiments were conducted on particles of various types: glass beads, Rilsan particles, and silt particles. The measurement conditions were varied: concentration, salinity, temperature, and flow rate.The results revealed reproducible trends:•Attenuation and ultrasonic velocity vary with concentration, in a quadratic and linear manner, respectively.•Salinity has a minimal effect on attenuation but significantly impacts velocity.•Temperature has no effect on attenuation and a limited effect on velocity.•Flow rate does not directly affect ultrasonic properties but contributes to understanding hydrodynamic processes in sediment transport or submarine flows.•Particles with non-smooth geometries, such as sediments, limit the variations in attenuation and velocity compared to smooth geometries, i.e., glass beads or Rilsan particles.•The developed experimental setup yielded reliable results, enabling the investigation of multiple influencing parameters simultaneously.Moreover, the experimental results were compared with numerical results based on McClements' work, using multiple scattering models by Lloyd and Berry, Waterman and Truell, and Ma et al. The discrepancies between experimental and numerical results prompted an advanced hydrodynamic study, conducted via finite element modeling using Comsol 2D.Les méthodes ultrasonores sont largement utilisées dans divers domaines d’évaluation et de caractérisation de milieux multiphasiques. En particulier, les ultrasons trouvent leur application dans l’établissement de diagnostic divers produits, dont des fluides pollués (traitement des eaux usées) ou des produits alimentaires (caractérisation des lipides et des protéines), ou encore des sédiments en suspension (évaluation de la concentration et la distribution des tailles de particules). Ce travail de recherche a pour but d'établir une relation entre les signaux ultrasonores et la concentration des particules, selon la nature, de la forme et de la distribution des particules. Dans cet objectif, un dispositif expérimental a été développé et mis en œuvre, et des modèles numériques de diffusion multiple ont été traités et validés. Des mesures ultrasonores ont été réalisées pour caractériser des suspensions en écoulement dynamique, avec une instrumentation spécifique conçue pour mesurer des propriétés ultrasonores effectives telles que l'atténuation et la vitesse. Les signaux ont été acquis et moyennés en régime stationnaire via le langage Python ; le post-traitement des signaux a été réalisée dans le domaine spectral via la FFT sur les échos d’intérêt ; les propriétés ultrasonores utiles ont été déduites en fonction de la fréquence via l'atténuation et la vitesse. Des expériences ont été menées sur des particules de différentes natures : billes de verre, particules de Rilsan et particules de limon. Les conditions de mesure ont été variées : concentration, salinité, température et débit. Les résultats obtenus font état de tendances reproductibles :•L'atténuation et la vitesse ultrasonores varient avec la concentration, respectivement de manière quadratique et linéaire.•La salinité a un effet minimal sur l'atténuation, mais impacte significativement la vitesse.•La température n'a aucun effet sur l'atténuation et un impact limité sur la vitesse.•Le débit n'affecte pas directement les propriétés ultrasonores, mais il aide à comprendre les processus hydrodynamiques dans les transports sédimentaires ou les flux sous-marins.•Les particules de géométrie non-lisse de type sédiment, limitent les variations d'atténuation et de vitesse par rapport aux géométries lisses, i.e. billes de verre ou particules de Rilsan.•Le dispositif expérimental développé a donné des résultats fiables, permettant l'investigation de plusieurs paramètres d’influence simultanément.De plus, les résultats expérimentaux ont été comparés aux résultats numériques basés sur les travaux de McClements, utilisant des modèles de diffusion multiple de Lloyd et Berry, Waterman et Truell et Ma et al. Les écarts entre les résultats expérimentaux et numériques ont motivé une étude hydrodynamique avancée via modélisation par éléments finis réalisée avec Comsol 2D
THE MURKY POLITICS OF THE SPANISH FRONTIER: SOME HISTORICAL AND HISTORIOGRAPHICAL STUDIES REGARDING THE ALLIANCES, HOSILITIES AND STRUGGLES FOR POWER ON BOTH SIDES OF THE PYRENEES FROM 846 TO 860
No full textUnderstanding Mycorrhizal Dynamics in Alfalfa Cultivation: Influence of Plant Age and Soil Tillage
No full textInternational audienceThis study explores the dynamics of mycorrhization in response to alfalfa age and tillage practices. Over two consecutive autumns (2022 and 2023), root samples from alfalfa plants aged between 1 and 5 years were collected in northeastern France from 10 farmers’ fields, including five managed with conventional plowing and five using simplified cultivation techniques (SCT). In each field, six subplots covering a total of 1.35 m² were selected to measure taproot biomass, alfalfa density and root mycorrhization rate. The results indicate that both alfalfa age and tillage practices significantly influence mycorrhizal symbiosis. The mycorrhizal intensity increased with alfalfa age, peaking at 5 years in this study. Under conventional plowing, it ranged from 3% (at 1 year) to 17% (at 5 years), whereas under SCT, it reached 40% at 5 years. The abundance of arbuscules followed a similar trend, being higher under SCT (12%) compared to conventional plowing (3%). These findings suggest that reduced tillage helps preserve mycelial networks, thereby facilitating more effective mycorrhizal colonization in alfalfa. In SCT fields, alfalfa density accounted for 19% of the variation in mycorrhization in 2022 and 40% in 2023, suggesting a positive impact of this practice on mycorrhizal dynamics and the importance of roots characteristics in enhancing mycorrhizal network efficiency. This study highlights the importance of sustainable agricultural practices in preserving mycorrhizal networks in alfalfa, emphasizing their key role in mycorrhizal dynamics and soil biological quality
La Communauté autonome basque et la gouvernance multiniveau dans l’Arc Atlantique : tensions et stratégies
No full textInternational audienceThis article explores the dynamics of multi-level governance in the Atlantic Arc, focusing on the strategy of the Basque Autonomous Community (BAC). Drawing on the theories of multi-level governance (Hooghe & Marks) and soft planning (Faludi), the study investigates how the BAC uses European frameworks such as INTERREG, TEN-T corridors, and the Atlantic macro-region to overcome institutional rigidity and defend its local priorities. Through the lens of strategic instrumentalization (Jacquot & Woll), the article demonstrates how the BAC leverages these European frameworks to balance transnational ambitions (macro-region) and territorial pragmatism (Atlantic Corridor). Furthermore, the reinterpretation of the Atlantic Arc as borderscapes (Rajaram & Grundy-Warr) reveals the tensions between institutional innovation and state-dominated governance, which hinder deeper transnational integration. In conclusion, the study highlights the complexity of regional strategies within a shifting European framework and emphasizes the need for enhanced dialogue across local, national, and transnational scales to achieve coherent governance in the Atlantic Arc.Cet article analyse les dynamiques de la gouvernance multiniveau dans l’Arc Atlantique, en se concentrant sur la stratégie de la Communauté autonome basque (CAB). En mobilisant les théories de la gouvernance multiniveau (Hooghe & Marks) et de l’aménagement souple (Faludi), l’étude examine comment la CAB utilise les instruments européens tels qu’INTERREG, les Réseaux transeuropéens de transport (RTE-T) et la macro-région atlantique pour surmonter les rigidités institutionnelles et défendre ses priorités locales. En s’appuyant sur le concept d’usages de l’Europe (Jacquot & Woll), l’article montre comment la CAB manipule ces cadres européens pour articuler ambitions transnationales (macro-région) et pragmatisme territorial (corridor Atlantique). En outre, la redéfinition de l’Arc Atlantique en tant que borderscape (Rajaram & Grundy-Warr) illustre les tensions entre innovation institutionnelle et domination étatique, freinant l’intégration transnationale. En conclusion, l’étude souligne la complexité des stratégies régionales dans un cadre européen en mutation, et la nécessité d’un dialogue renforcé entre les échelles locales, nationales et transnationales pour une gouvernance cohérente de l’Arc Atlantique
Đổi mới sáng tạo để thoát bẫy nghèo khó, bẫy thu nhập trung bình và bẫy tăng trưởng trung bình?
No full textIn the context of globalization and intensifying economic competition, Vietnam has achieved remarkable progress in economic growth and improving living standards over the past few decades. However, significant challenges persist, particularly the risk of falling into development traps such as the poverty trap, the middle-income trap, and the average growth rate trap.Vietnam is currently classified as a lower-middle-income country, with a GDP per capita of approximately USD 4,700 in 2024. According to a World Bank report (Coppola et al., 2024), achieving the goal of becoming a high-income country by 2045 requires Vietnam to sustain a high and consistent economic growth rate. This article analyzes the core factors driving economic growth, defines the types of development traps, and proposes innovation- and technology-based (I&T) solutions to help Vietnam overcome these challenges. The analysis draws on data and insights from official sources, such as the General Statistics Office of Vietnam (GSO) and international organizations, to substantiate the arguments. This article does not address the risks posed by U.S. tariff policies, which significantly impact Vietnam—one of the economies heavily reliant on foreign markets—and contribute to the reconfiguration of the global trade order.Trong bối cảnh toàn cầu hóa và cạnh tranh kinh tế ngày càng gay gắt, Việt Nam đã đạt được những thành tựu đáng kể trong việc tăng trưởng kinh tế và cải thiện đời sống người dân trong vài thập kỷ qua. Tuy nhiên, những thách thức lớn vẫn còn tồn tại, đặc biệt là nguy cơ rơi vào các bẫy phát triển như bẫy nghèo khó, bẫy thu nhập trung bình và bẫy tốc độ tăng trưởng trung bình.Việt Nam hiện đang ở nhóm các nước có thu nhập trung bình thấp với GDP bình quân đầu người đạt khoảng 4.700 USD vào năm 2024. Theo báo cáo của Ngân hàng Thế giới - World Bank (Coppola và cộng sự, 2024) để đạt được mục tiêu trở thành quốc gia có thu nhập cao vào năm 2045, Việt Nam cần duy trì tốc độ tăng trưởng kinh tế cao và bền vững. Bài viết này sẽ phân tích các yếu tố cốt lõi thúc đẩy tăng trưởng kinh tế, định nghĩa các loại bẫy phát triển, đồng thời đề xuất các giải pháp dựa trên đổi mới sáng tạo (ĐMST) để Việt Nam vượt qua những thách thức này. Chúng tôi cũng sẽ kết hợp các dữ liệu và phân tích từ các nguồn chính thức như Tổng cục Thống kê Việt Nam (GSO) và các tổ chức quốc tế để làm rõ các luận điểm. Bài viết này không nói đến các nguy cơ đến từ chính sách thuế quan của Mỹ, đang có tác động mạnh mẽ đến Việt Nam, là một trong những nền kinh tế rất phụ thuộc vào thị trường nước ngoài, và gây sắp xếp lại trật tự thương mại toàn cầu
