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Spatiotemporal relationships between rainfall indices and crop yields in the Sudano-Sahelian zone of Cameroon
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/614417/) * Autres projets (id;sigle;titre): ;INNOVACC;(EU) Innovation pour l’Adaptation au Changement Climatique// ;DeSIRA;(EU) Development Smart Innovation through Research in Agriculture//International audienceIn the Sudano-Sahelian zone of Cameroon, agriculture — predominantly rainfed — constitutes a major economic sector, underpinning food security but remaining vulnerable to rainfall variability. This study explores statistical relationships between 25 rainfall indices and the yields of maize (Zea mays L.) from 1999 to 2021 and cotton (Gossypium hirsutum L.) from 1991 to 2010, employing Pearson correlation tests across temporal and spatial scales. At the temporal scale, results indicate that maize and cotton yields respond similarly to two indices: the end of the rainy season (EOS) and cumulative dry spells (CDS15). A longer rainy season is associated with higher yields for both crops, whereas dry spells exert a negative influence across the entire study area. However, spatial analyses reveal significant local variations in crop responses. Specifically, maize yields exhibit positive correlations with indices such as rainfall amount (PRCPSEAS), rainy days (R1mm), wet days (R20mm), season length (SL) in the northern and southwestern parts of the study area, reflecting the importance of consistent moisture availability for optimal growth. Conversely, cotton yields are strongly negatively correlated with these same indices in the northern, northwestern, central, and southeastern parts, likely reflecting the crop's lower tolerance for excessively humid conditions. The findings highlight the need for crop-specific adaptation strategies to rainfall variability, including the selection of appropriate crop varieties, adjustments to planting calendars, improved water management practices, particularly in the context of increasing rainfall trends. Policymakers could invest in localized agro-climatic forecasting systems and improve the integration of climate data into agricultural advisory services
The impact of landscape and prey on psyllophagous ladybird communities in a tropical environment
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/614096/) * Autres projets (id;sigle;titre): RE0022961;CREME;(REU) Projet Conservation et Restauration des Espèces et Milieux Endémiques//International audienceThis study examines the community composition and structure of psyllophagous ladybirds in a tropical environment, focusing on their interactions with psyllids as a food resource. It investigates the effects of prey availability and landscape composition on the structure of all ladybird species associated with psyllids and on the presence and abundance of species whose life cycles depend on psyllids. Sampling was conducted in Reunion island on two psyllid-infested plant species, Leucaena leucocephala and Acacia heterophylla. Ladybirds and psyllids were regularly collected during two years using a thermal aspirator, and visual inspection was conducted at eleven sites visited monthly. In this study, 16 ladybird species were identified, and only juveniles from Coccinella septempunctata, Exochomus laeviusculus, and Olla v-nigrum were frequently present, suggesting they can complete their biological cycle on psyllids. The structure of psyllophagous ladybird communities in a tropical environment is driven by the psyllid host plant and the monthly average temperature. When studied separately, food resources or landscape variables did not affect significantly the communities. The distribution of Coccinella septempunctata is limited to high elevations, where it is recognized as an aphid-eating species, mainly in its juvenile form. Conversely, at low elevation, we encountered juvenile individuals of the generalist species Exochomus laeviusculus and the specialist species Olla v-nigrum. The presence and abundance of the generalist was positively influenced by the landscape and the presence of the specialist positively by prey abundance only
A combined recombinase polymerase amplification CRISPR/Cas12a assay for detection of Fusarium oxysporum f. sp. cubense tropical race 4
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/613922/)International audienceThe soilborne pathogen Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4) is currently devastating banana production worldwide. Once introduced, it is not possible to eradicate the pathogen from soils where it can survive for decades. The only management option available then is to replace Foc TR4-susceptible with -resistant varieties. Timely detection of the pathogen, however, is an important strategy to prevent the introduction of Foc TR4 into new areas and prevent its spread from infested sites. In this study, a single-tube detection technique was developed by combining recombinase polymerase amplification (RPA) and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a technology (RPA-Cas12a) for detection of Foc TR4. The RPA-Cas12a assay was conducted isothermally, had a sensitivity of up to 10 fg target DNA and did not cross react with any of the 76 non-target isolates included in the specificity testing. The RPA-Cas12a assay detected Foc TR4 from naturally infected banana samples collected in the field and visualization was possible with the naked eye under LED blue light transillumination. The method can be integrated with inexpensive fluorescent or electronic detection devices to accelerate Foc TR4 in-field detection and, thereby, fast-track disease containment strategies
Trust in scientists and their role in society across 68 countries
No full textInternational audienceScience is crucial for evidence-based decision-making. Public trust in scientists can help decision makers act on the basis of the best available evidence, especially during crises. However, in recent years the epistemic authority of science has been challenged, causing concerns about low public trust in scientists. We interrogated these concerns with a preregistered 68-country survey of 71,922 respondents and found that in most countries, mScience is crucial for evidence-based decision-making. Public trust in scientists can help decision makers act on the basis of the best available evidence, especially during crises. However, in recent years the epistemic authority of science has been challenged, causing concerns about low public trust in scientists. We interrogated these concerns with a preregistered 68-country survey of 71,922 respondents and found that in most countries, most people trust scientists and agree that scientists should engage more in society and policymaking. We found variations between and within countries, which we explain with individual- and country-level variables, including political orientation. While there is no widespread lack of trust in scientists, we cannot discount the concern that lack of trust in scientists by even a small minority may affect considerations of scientific evidence in policymaking. These findings have implications for scientists and policymakers seeking to maintain and increase trust in scientists.ost people trust scientists and agree that scientists should engage more in society and policymaking. We found variations between and within countries, which we explain with individual-and country-level variables, including political orientation. While there is no widespread lack of trust in scientists, we cannot discount the concern that lack of trust in scientists by even a small minority may affect considerations of scientific evidence in policymaking. These findings have implications for scientists and policymakers seeking to maintain and increase trust in scientists
Submarine ash megabed fed by far-traveled, shoreline-crossing pyroclastic currents from a large explosive volcanic eruption
No full textInternational audienceLarge explosive volcanic eruptions from island volcanoes deliver vast quantities of ash to the marine environment. While many of the transport pathways are understood, those from shoreline-crossing or submarine pyroclastic currents, and their transformation into water-supported gravity flows, remain poorly constrained. We report the discovery by International Ocean Discovery Program (IODP) deep drilling of a 200-meter-thick ash megabed buried in rift basins of the South Aegean Volcanic Arc. The >73–cubic kilometer ash deposit originates from the Kos Plateau Tuff caldera-forming eruption, which occurred 161 thousand years ago, >120 kilometers to the east. The ash forms a chemically uniform, graded megabed lacking bioturbation, interpreted as having been emplaced by a stream of eruption-fed turbidity currents. Bioclastic debris within the ash provides evidence of widespread destruction of marine ecosystems. Large volcanic eruptions can remodel the seafloor landscape, deposit thick ash turbidites, and destroy marine biota on island arc–wide scales in short-lived, catastrophic events
Le contrôle européen des aides d’État comme remède à la non-imposition internationale: A propos de l'arrêt CJUE, 10 sept. 2024, Commission c/ Irlande, Apple Sales International Ltd et Apple Operations International Ltd, C‑465/20 P
No full textInternational audienceAccording to the European Commission, Ireland had granted illegal State aid tothe Apple group through tax rulings relating to the tax treatment of profits derived fromApple’s activities outside the United States. The Court of Justice of the European Union held that the General Court, which had annulled the Commission’s decision, had erred in holding that the Commission had not sufficiently demonstrated that the IP licenses held by the Irish subsidiaries and the associated profits were to be allocated to their Irish branches. In particular, the General Court erred in holding that the Commission’s main argument was based on incorrect assessments of the normal taxation under Irish law. In particular, the CJEU confirmed the Commission’s approach that the activities of the Irish branches should be compared not with the activities of the parent company Apple Inc. but with those of the head offices of the Irish subsidiaries.Discussing the usefulness of EU State aid procedures for addressing competition distortions related with companies of non-EU countries, the article shows that the Court’s ruling has a limited scope and does not overturn the Court’s previous case-law in State aid matters. Meanwhile, it also suggests that the Court’s reasoning is based on a questionable use of the “Authorized OECD Approach” for the attribution of profits to permanent establishments, on an erroneous interpretation of the OECD principles and on an approach “by exclusion”, relaxing thereby the burden of proof in State aid procedures
Évaluation des connaissances des parents sur les risques sanitaires de l’exposition au bruit des enfants de 0 à 9 ans, à La Réunion
No full textBackground: Noise exposure in young children is responsible for sleep and neurodevelopmental disorders, impacting their health, which represents a major public health issue. Preventing risks for this vulnerable and dependent population involves awareness among parents. There seems to be a lack of information regarding the risks caused by noise, as just under half of the parents feel adequately informed about the health effects of noise. The objective is to assess parents' knowledge of the health risks related to their children's exposure to noise in Reunion.Method: This is a descriptive, cross-sectional observational study base on self-administered questionnaires distributed to parents of children aged 0 to 9 years at general medicine, pediatric, midwifery practices, and PMI services from July 1st to October 31st, 2024.Results: 205 questionnaires were analyzed. The average score obtained by participants on the knowledge test was 26.3 out of 34. 47% had already been made aware of the risks of noise exposure, 27% thought they were sufficiently informed. Significant differences were found based on the parents' age, educational level, socio-professional category, and number of children per parent.Conclusion: Parents are aware of the main health effects of noise, but these results remain improvable. This study reinforces the role of general practitioners in raising awareness about noise and underscores the need for clear recommendations from French health authorities. Special attention should be given to vulnerable populations to reduce health inequalities.Introduction : L’exposition au bruit des jeunes enfants est responsable de troubles du sommeil et du neurodéveloppement impactant leur santé, ce qui représente un véritable enjeu de santé publique. La prévention de cette population fragile et non autonome passe par la sensibilisation des parents. Il semble exister un manque d’information quant aux risques engendrés par le bruit puisqu’un peu moins d’un parent sur deux pense être plutôt bien informé sur les effets sanitaires du bruit. L’objectif est d’évaluer les connaissances des parents, quant aux risques sanitaires de l’exposition au bruit de leurs enfants, à La Réunion.Méthode : Il s'agit d'une étude observationnelle, descriptive, transversale à partir d’auto-questionnaires distribués aux parents d’enfants de 0 à 9 ans dans des cabinets de médecine générale, pédiatrie, sages-femmes et services de PMI, du 1er juillet au 31 octobre 2024.Résultats : 205 questionnaires ont été analysés. La moyenne obtenue par les participants au test de connaissances était de 26,3 sur 34. 47% avaient déjà été sensibilisés aux risques du bruit et 27% se pensaient suffisamment informé. Des différences significatives ont été observées selon l’âge, le niveau d’étude, la catégorie socio-professionnelle et le nombre d’enfants par parent.Conclusion : Les parents connaissent les principaux effets sanitaires du bruit mais ces résultats restent perfectibles. Cette étude renforce le rôle du médecin généraliste dans la sensibilisation au bruit et souligne la nécessité pour les autorités sanitaires françaises d’établir des recommandations. Une attention particulière doit être accordée aux populations vulnérables afin de limiter les inégalités de santé
Introduction de l'inférence statistique au modèle DEA : une application de BOOTSTRAP aux scores de performance des IMF des pays en Développement.
No full textInternational audienceUsing the research of Simar and Wilson, this article applies the Bootstrap to the performance scores derived from the Data Envelopment Analysis (DEA) model of MFIs in developing countries. Then, it apprehend the sensitivity of these scores to exogenous shocks particulary the macroeconomics variables.The estimated DEA frontier effectively differentiates between efficient MFIs located on this frontier and inefficient MFIs located below it.Au moyen des travaux de Simar et Wilson, cet article applique le Bootstrap aux scores de performance issus du modèle Data Envelopment Analysis (DEA) des IMF des pays en développement. Ensuite il saisit la sensibilité de ces scores aux chocs exogènes. La frontière DEA estimée établit effectivement la différentiation entre les IMF efficientes situées sur cette frontière et les IMF inefficientes localisées en dessous de celle-ci
Technological Characterization and Socioeconomic Significance of Djir, a Fermented Cereal Flour Consumed in Chad
No full textInternational audienceAims: To characterize the traditional processing technology, hygiene practices, and socioeconomic significance of djir production in Chad, with a particular focus on women’s empowerment, food safety, and commercialization potential. Study Design: Cross-sectional descriptive study based on field surveys, observational hygiene assessments, and technological process documentation. Place and Duration of Study: The study was conducted in five locations across Chad namely N'Djamena, Abéché, Oum-Hadjer, Guéréda, and Ati between October 2021 and October 2022. Methodology: A structured field survey was administered to 255 participants, including 15 female djir producers, 100 vendors, and 140 consumers. Data collection focused on sociodemographic characteristics, processing techniques, fermentation practices, hygiene behaviors, pricing, and consumer perceptions. Hygiene assessments were based on observational checklists and scoring systems adapted from prior literature. Results: djir production was found to be exclusively female-led, with high levels of illiteracy (53.3%) and limited hygiene training. The artisanal process, spanning 2-3 weeks, included partial dehulling, spontaneous fermentation (86.7%), and sun-drying. Only 13% of producers disinfected their equipment, and 90% of units operated under poor hygienic conditions. Price disparities were evident across regions (1,000-1,600 FCFA/kg). Although 97.86% of consumers were familiar with djir, only 31% perceived health benefits, and 3% reported adverse effects such as constipation. Conclusion: This study presents the first detailed process diagram of djir production and highlights critical gaps in fermentation control and hygiene. To improve product safety and support women-led food systems, the integration of starter cultures, hygiene training, and gender-sensitive development policies is recommended. djir serves as both a culturally important food and a tool for rural women's economic empowerment in Chad
Tracking the global pulse: the first public twitter dataset from FIFA world cup
No full texthttps://data.mendeley.com/datasets/gw3mcnbkwr/2.International audienceThe success of the recent World Cup tournament has captured unprecedented global attention, leading to a substantial increase in online discourse that reflects the diverse sentiments and opinions of fans across the globe. Understanding this online conversation is essential, particularly in the context of significant sporting events such as the recent tournament held in Qatar from November 20 to December 18, 2022. However, access to social media data is often restricted, posing a significant obstacle to the comprehensive study of online sports discourse. To address this challenge and enhance the capabilities of the Computational Social Science research community, we present a large-scale dataset comprising tweets related to the World Cup. This multilingual dataset encompasses over 28 million posts from over 2.5 million unique users, documenting key events surrounding the tournament. Our dataset is meticulously curated and thoroughly documented, providing a valuable resource for researchers investigating critical social and scientific issues, including bot detection, sentiment analysis, hate speech and aggression identification, and the dissemination of misinformation. The dataset is publicly accessible at: https://data.mendeley.com/datasets/gw3mcnbkwr/2