Coordination et qualité dans les filières agricoles du Sud

The objective of the project is to assess the strengths and weaknesses of different forms of coordination in the development of quality chains in developing countries. Such forms of coordination include: signs of quality (labels, brands, geographical references); horizontal coordination (producers' or traders' associations); vertical coordination (personalized relationships, contracts, integration). Our project is attempting to: (i) characterize problems with quality; (ii) characterize the diversity of forms of coordination to deal with quality problems; (iii) assess the effectiveness of forms of coordination and the potential role of government to strengthen it. The project is based on four case studies of specific quality commodity chains ("safe" vegetables in Vietnam, grain in Mali, special coffees in the Dominican Republic, palm oil in Côte d'Ivoire and Cameroon), as well as workshops that bring together researchers from CIRAD,INRA, universities and countries of the South. Setting up a framework to analyze the relationship between coordination and quality problems is one of the pillars of the project. Problems with quality have been characterized in the four case studies, highlighting the increasing costs and measurement errors between physical quality problems (found in all commodity chains), flavor (palm oil and coffee), safety (vegetables in Vietnam) and ethics (coffee). Despite the incentive for integration predicted by institutional theories dealing with quality problems, personalized relationships predominate in the four commodity chains. Such personalized relationships are very resilient but they are not an effective tool to promote the development of quality beyond a minimal level and only partially eliminate opportunism. The integration between production and marketing is observed to take place successfully in a number of vegetable cooperatives in Vietnam. Furthermore, the conditions for successful collective action have been developed more particularly in the case study involving Mali, revealing the effectiveness of coupling government (at the local level) and private sanctions in case of non-compliance with commitments on the requirements for membership in stakeholders' associations. The project has enabled fruitful exchanges between INRA and CIRAD researchers regarding the layout of analytical frameworks as well as on the research outputs. These exchanges led to the production of several papers, a supported thesis and two master science dissertations. In each case study, one type of coordination method was reviewed using an analysis approach (vertical integration in the case of Vietnam, collective action in the case of Mali, signs for palm oil, while the coffee study has not yet been completed). It would be advisable to continue analytical work on all methods of coordination for the four case studies. Cooperation arrangements could be maintained in the framework of the Moisa UMR (Joint Research Unit). ...French Abstract : L'objectif du projet est d'évaluer les forces et faiblesses de différents modes de coordination dans le développement de démarches qualité dans les pays du sud. Les modes de coordination recouvrent : les signes de qualité (labels, marques, référents géographiques) ; la coordination horizontale (associations de producteurs ou de commerçants) ; la coordination verticale (relations personnalisées, contrats, intégration). Notre projet cherche à : (i) caractériser les problèmes de qualité ; (ii) caractériser la diversité des modes de coordination répondant aux problèmes de qualité; (iii) évaluer l'efficacité des modes de coordination et le rôle potentiel de l'Etat pour la renforcer. Le projet s'appuie sur quatre études de cas de filières de qualité spécifique (légumes sains au Vietnam, céréales au Mali, cafés Spéciaux en République dominicaine, huile de palme en Côte d'Ivoire et au Cameroun), ainsi que sur des ateliers de mise en commun associant des chercheurs du CIRAD, de l'INRA, de l'université et des pays du Sud. La mise en forme d'un cadre d'analyse de la relation entre la coordination et les problèmes de qualité est un des acquis du projet. Les problèmes de qualité ont été caractérisés dans les quatre études de cas en mettant l'accent sur les coûts et erreurs de mesure qui vont croissant entre les problèmes de qualité physique (présents sur toutes les filières), gustative (huile de palme et café), sanitaire (légumes au Vietnam) et éthique (café). Malgré l'incitation à l'intégration prédite par la théorie en situation de problèmes de qualité, ce sont les relations personnalisées qui dominent dans les quatre filières. Ces relations personnalisées ont une grande résilience mais permettent difficilement le développement de la qualité au-delà d'un niveau minimal et n'éliminent que partiellement l'opportunisme. L'intégration entre production et commercialisation est observée avec succès dans le cas de quelques coopératives de légumes au Vietnam. Par ailleurs, les conditions de succès de l'action collective ont été particulièrement approfondies pour l'étude de cas du Mali, révélant l'efficacité du couplage des sanctions publiques (à l'échelle locale) et privées en cas de non-respect d'engagements sur la qualité des membres des associations de commerçants. Le projet a permis de fructueux échanges entre chercheurs INRA et CIRAD sur le plan des cadres d'analyse, ainsi que des résultats de recherche. Ces échanges se sont traduits par la rédaction de plusieurs articles, une thèse soutenue et deux mémoires de stage. Dans chaque étude de cas, un type de mode de coordination a fait plus particulièrement l'objet d'analyses (l'intégration verticale dans le cas du Vietnam, l'action collective dans le cas du Mali, les signaux pour l'huile de palme, tandis que l'étude sur le café est encore incomplète). Il serait intéressant de poursuivre le travail d'analyse de l'ensemble des modes de coordination pour les quatre études de cas. Les collaborations engagées pourront être maintenues dans le cadre de l'UMR MOISA.QUALITY; COORDINATION; INSTITUTIONAL ECONOMICS; COMMODITY CHAIN; FARMERS' ORGANISATIONS; DEVELOPING COUNTRIES

Sharp interface limits of phase-field models

The use of continuum phase-field models to describe the motion of well-defined interfaces is discussed for a class of phenomena, that includes order/disorder transitions, spinodal decomposition and Ostwald ripening, dendritic growth, and the solidification of eutectic alloys. The projection operator method is used to extract the ``sharp interface limit'' from phase field models which have interfaces that are diffuse on a length scale $\xi$. In particular,phase-field equations are mapped onto sharp interface equations in the limits $\xi \kappa \ll 1$ and $\xi v/D \ll 1$, where $\kappa$ and $v$ are respectively the interface curvature and velocity and $D$ is the diffusion constant in the bulk. The calculations provide one general set of sharp interface equations that incorporate the Gibbs-Thomson condition, the Allen-Cahn equation and the Kardar-Parisi-Zhang equation.Comment: 17 pages, 9 figure

The Moment Guided Monte Carlo method for the Boltzmann equation

In this work we propose a generalization of the Moment Guided Monte Carlo method developed in [11]. This approach permits to reduce the variance of the particle methods through a matching with a set of suitable macroscopic moment equations. In order to guarantee that the moment equations provide the correct solutions, they are coupled to the kinetic equation through a non equilibrium term. Here, at the contrary to the previous work in which we considered the simplified BGK operator, we deal with the full Boltzmann operator. Moreover, we introduce an hybrid setting which permits to entirely remove the resolution of the kinetic equation in the limit of infinite number of collisions and to consider only the solution of the compressible Euler equation. This modification additionally reduce the statistical error with respect to our previous work and permits to perform simulations of non equilibrium gases using only a few number of particles. We show at the end of the paper several numerical tests which prove the efficiency and the low level of numerical noise of the method.Comment: arXiv admin note: text overlap with arXiv:0908.026

In-situ start and end of growing season dates of major European crop types from France and Bulgaria at a field level

Crop phenology data offer crucial information for crop yield estimation, agricultural management, and assessment of agroecosystems. Such information becomes more important in the context of increasing year-to-year climatic variability. The dataset provides in-situ crop phenology data (first leaves emergence and harvest date) of major European crops (wheat, corn, sunflower, rapeseed) from seventeen field study sites in Bulgaria and two in France. Additional information such as the sowing date, area of each site, coordinates, method and equipment used for phenophase data estimation, and photos of the France sites are also provided. The georeferenced ground-truth dataset provides a solid base for a better understanding of crop growth and can be used to validate the retrieval of phenological stages from remote sensing data

In-situ start and end of growing season dates of major European crop types from France and Bulgaria at a field level

Crop phenology data offer crucial information for crop yield estimation, agricultural management, and assessment of agroecosystems. Such information becomes more important in the context of increasing year-to-year climatic variability. The dataset provides in-situ crop phenology data (first leaves emergence and harvest date) of major European crops (wheat, corn, sunflower, rapeseed) from seventeen field study sites in Bulgaria and two in France. Additional information such as the sowing date, area of each site, coordinates, method and equipment used for phenophase data estimation, and photos of the France sites are also provided. The georeferenced ground-truth dataset provides a solid base for a better understanding of crop growth and can be used to validate the retrieval of phenological stages from remote sensing data.This publication is the result of the Action CA17134 SENSECO (Opticalsynergies for spatiotemporal sensing of scalable ecophysiological traits) funded by COST (European Cooperation in Science and Technology, www.cost.eu, accessed on March 17, 2023). We thank Tiphaine Tallec for the in-situ data of the French sites, mainly funded by the Institut National des Sciences de l'Univers (INSU) through the ICOS ERIC and the OSR SW observatory (https://osr.cesbio.cnrs.fr/). Facilities and staff are funded and supported by the Observatory Midi-Pyrenean, the University Paul Sabatier of Toulouse 3, CNRS (Centre National de la Recherche Scientifique), CNES (Centre National d'Etude Spatial) and IRD (Institut de Recherche pour le Développement). We further thank Dessislava Ganeva for the in-situ data of the Bulgarian sites. SB was by partially supported by Generalitat Valenciana SEJIGENT program (SEJIGENT/2021/001) and European Union NextGenerationEU (ZAMBRANO 21-04)

Is there an optimal strategy for real-time continuous glucose monitoring in pediatrics? A 12-month French multi-center, prospective, controlled randomized trial (Start-In!)

AIM: To compare the efficacy of three strategies for real-time continuous glucose monitoring (RT-CGM) over 12 months in children and adolescents with type 1 diabetes. METHODS: A French multicenter trial (NCT00949221) with a randomized, controlled, prospective, open, and parallel-group design was conducted. After 3 months of RT-CGM, patients were allocated to one of three groups: return to self-monitoring of blood glucose, continuous CGM (80% of the time), or discontinuous CGM (40% of the time). The primary outcome was hemoglobin A1c (HbA1c) levels from 3 to 12 months. The secondary outcomes were acute metabolic events, hypoglycemia, satisfaction with CGM and cost. RESULTS: We included 151 subjects, aged 2 to 17 years, with a mean HbA1c level of 8.5% (SD0.7; 69 mmol/mol). The longitudinal change in HbA1c levels was similar in all three groups, at 3, 6, 9 and 12 months. The medical secondary endpoints did not differ between groups. The rate of severe hypoglycemia was significantly lower than that for the pretreatment year for the entire study population. Subjects reported consistent use and good tolerance of the device, regardless of age or insulin treatment. The use of full-time RT-CGM for 3 months costs the national medical insurance system €2629 per patient. CONCLUSION: None of the three long-term RT-CGM strategies evaluated in pediatric type 1 diabetes was superior to the others in terms of HbA1c levels. CGM-use for 3 months decreased rates of severe hypoglycemia. Our results confirm the feasibility of long-term RT-CGM-use and the need to improve educational support for patients and caregivers

The combination of a blood test and Fibroscan improves the non-invasive diagnosis of liver fibrosis

Background and aims: Blood tests and liver stiffness evaluation (LSE) by ultrasonographic elastometry are accurate tools for diagnosing liver fibrosis. We evaluated whether their synchronous combination in new scores could improve the diagnostic accuracy and reduce liver biopsy requirement in algorithm. Methods: Three hundred and ninety patients with chronic liver disease of miscellaneous causes were included. Five blood fibrosis tests were evaluated: APRI, FIB-4, Hepascore, Fibrotest and FibroMeter. The reference was fibrosis Metavir staging. Results: Diagnosis of significant fibrosis (Metavir F≥2). The most accurate synchronous combination was FibroMeter+LSE, which provided a significantly higher area under the receiver operating characteristic curve (0.892) than LSE alone (0.867, P=0.011) or Fibrometer (0.834, P<10−3). An algorithm using the FibroMeter+LSE combination and then a liver biopsy in indeterminate cases had 91.9% diagnostic accuracy and required significantly fewer biopsies (20.2%) than previously published Bordeaux algorithm (28.6%, P=0.02) or sequential algorithm for fibrosis evaluation (SAFE) (55.7%, P<10−3). The Angers algorithm performance was not significantly different between viral hepatitis and other causes. Diagnosis of cirrhosis. The most accurate synchronous combination was LSE+FibroMeter, which provided ≥90% predictive values for cirrhosis in 90.6% of patients vs 87.4% for LSE (P=0.02) and 57.9% for FibroMeter (P<10−3). An algorithm including the LSE+FibroMeter combination, and then a liver biopsy in indeterminate cases, had a significantly higher diagnostic accuracy than the SAFE algorithm (91.0 vs 79.8%, P<10−3), and required significantly fewer biopsies than the Bordeaux algorithm (9.3 vs 25.3%, P<10−3). Conclusion: The synchronous combination of a blood test plus LSE improves the accuracy of the non-invasive diagnosis of liver fibrosis and, consequently, markedly decreases the biopsy requirement in the diagnostic algorithm, notably to <10% in cirrhosis diagnosis

Normosmic Congenital Hypogonadotropic Hypogonadism Due to TAC3/TACR3 Mutations: Characterization of Neuroendocrine Phenotypes and Novel Mutations

CONTEXT: TAC3/TACR3 mutations have been reported in normosmic congenital hypogonadotropic hypogonadism (nCHH) (OMIM #146110). In the absence of animal models, studies of human neuroendocrine phenotypes associated with neurokinin B and NK3R receptor dysfunction can help to decipher the pathophysiology of this signaling pathway. OBJECTIVE: To evaluate the prevalence of TAC3/TACR3 mutations, characterize novel TACR3 mutations and to analyze neuroendocrine profiles in nCHH caused by deleterious TAC3/TACR3 biallelic mutations. RESULTS: From a cohort of 352 CHH, we selected 173 nCHH patients and identified nine patients carrying TAC3 or TACR3 variants (5.2%). We describe here 7 of these TACR3 variants (1 frameshift and 2 nonsense deleterious mutations and 4 missense variants) found in 5 subjects. Modeling and functional studies of the latter demonstrated the deleterious consequence of one missense mutation (Tyr267Asn) probably caused by the misfolding of the mutated NK3R protein. We found a statistically significant (p<0.0001) higher mean FSH/LH ratio in 11 nCHH patients with TAC3/TACR3 biallelic mutations than in 47 nCHH patients with either biallelic mutations in KISS1R, GNRHR, or with no identified mutations and than in 50 Kallmann patients with mutations in KAL1, FGFR1 or PROK2/PROKR2. Three patients with TAC3/TACR3 biallelic mutations had an apulsatile LH profile but low-frequency alpha-subunit pulses. Pulsatile GnRH administration increased alpha-subunit pulsatile frequency and reduced the FSH/LH ratio. CONCLUSION: The gonadotropin axis dysfunction associated with nCHH due to TAC3/TACR3 mutations is related to a low GnRH pulsatile frequency leading to a low frequency of alpha-subunit pulses and to an elevated FSH/LH ratio. This ratio might be useful for pre-screening nCHH patients for TAC3/TACR3 mutations

Skin Vaccination against Cervical Cancer Associated Human Papillomavirus with a Novel Micro-Projection Array in a Mouse Model

Background: Better delivery systems are needed for routinely used vaccines, to improve vaccine uptake. Many vaccines contain alum or alum based adjuvants. Here we investigate a novel dry-coated densely-packed micro-projection array skin patch (Nanopatch (TM)) as an alternate delivery system to intramuscular injection for delivering an alum adjuvanted human papillomavirus (HPV) vaccine (Gardasil (R)) commonly used as a prophylactic vaccine against cervical cancer