Methodological pathways to improvements of evaluation approaches: the case of irrigated agriculture evaluation

Cette synthèse montre l'évolution des méthodes d'évaluation dans le champ de l'agriculture irriguée, vers une tendance à des méthodologies intégrées. Elle propose quelques outils méthodologiques pour améliorer le processus d'évaluation. / Background: Irrigated agriculture is often evaluated but few reviews of evaluation methodology adapted to this object are available in the literature. Besides, recommendations to improve evaluation in this field are lacking. Purpose: The purpose of the paper is to contribute filling this gap. Setting: Not applicable. Intervention: Not applicable. Research Design: Not applicable. Data Collection and Analysis: Desk review. Findings: This review shows the evolution of evaluation methodology in the field of irrigated agriculture pointing out a trend towards more comprehensive methodologies. The review also suggests some methodological tools to improve evaluation process

Micromechanical constitutive modeling of tensile and cyclic behaviors of nano-clay reinforced metal matrix nanocomposites

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J integral as a fracture criterion of rubber-like materials using the intrinsic defect concept

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Analyse de systèmes et des stratégies d'irrigation pour le blé dur en Tunisie

International audienceTo help identify an irrigation system and irrigation strategy to improve durum wheat production in the context of water scarcity of Tunisia, the PILOTE (operative water balance and yield estimation) model and the RAIEOPT (furrow irrigation) model are coupled. The first step was to choose the most efficient surface irrigation system (SIS) with its irrigation strategy. On the basis of field experiment data, an economic-optimisation model allows the identification of the best SIS with its irrigation strategy for conditions of water scarcity in Tunisia. The furrow system with an inter-furrow spacing of 1.5 m and a strategy which consists on irrigating when the soil water reserve is 80% depleted are selected by the optimisation model. Using "deficit irrigation " principles which establish a ratio between the amount of water applied to a given crop and a economically acceptable target yield value, irrigation strategies for sprinkler and the selected SIS are identified. RAIEOPT-PILOTE coupling is used to perform this analysis for SIS. The results of the simulations, based on climatic data spanning the last 20 years, raise questions about the suitability of sprinkler irrigation method for clay soil conditions in Tunisia. This paper also aims to contribute to future economic studies that will take into account social constraints. This study should allow managers to choose between sprinkler irrigation methods and SIS modernisation.Dans le but de proposer un systèmes d`irrigation avec sa stratégie d`usage visant à améliorer la production du blé dur dans le contexte de pénurie d`eau de la Tunisie, le modèle PILOTE (un modèle opérationnel estimant le bilan hydrique et le rendement) et le modèle RAIEOPT (modèle d`irrigation à la raie) sont couplés. Un premier volet de cet article traite du choix du système d`irrigation de surface (SIS) le plus efficient accompagné de sa stratégie de mise en oeuvre. L`irrigation à la raie avec un espacement de 1.5 m avec la stratégie consistant à irriguer lorsque la réserve en eau du sol est épuisée à 80% ont été sélectionnés par le modèle d`optimisation économique. Sur la base du concept '`irrigation déficitaire`` établissant un rapport entre la quantité d`eau apportée et un objectif de rendement économiquement acceptable, des stratégies d`irrigation pour l`aspersion et le SIS sélectionné sont identifiées. Le couplage des modèle RAIEOPT-PILOTE est utilisé pour réaliser cette analyse pour le cas du SIS. Les résultats de la simulation, basés sur une série climatique de 20 année, soulève la question relative à l`intérêt de l`aspersion dans le cas des sols argileux en Tunisie. Ce article peut être considéré comme une contribution à de futures études économiques devant tenir compte des contraintes sociales. Ce travail devrait permettre aux gestionnaires de choisir entre aspersion et modernisation de l`irrigation de surface

Experimental and finite element investigation of void nucleation in rubber-like materials

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Participation in a complex and conflicting context: implementing a shared diagnosis in a Northern Tunisia irrigation scheme

International audiencePromoting innovation to improve both productivity and sustainability of irrigated farming systems is crucial for the first question addressed within the Sustainable Development Goals process led by the United Nations. This is a complex task that requires methods and processes which include a diversity of knowledge. For this reason, participatory approaches have been increasingly encouraged. A broad range of methods have been developed in the literature. However, debates on the effectiveness of the results, including questions on how different stakeholders influence results and how the context influences platform processes, remain theoretical. In this article, the authors evaluate the results of a participatory diagnosis aiming to identify the constraints and possible innovations to improve agricultural production in the Brahmi irrigation scheme in Tunisia. The process was implemented with individual interviews and focus groups operationalized through two types of platforms, 'Community of Practice (CoP)' and 'Learning and Practice Alliance (LPA)'. We highlighted that both CoP and LPA offer fruitful platforms for the interaction of all stakeholders. However, the results could be biased by the context and the expectations and strategies of powerful participants. Individual interviews are complementary to focus group results, especially in situations where open or latent conflicts exist

Surgery in vertebral fracture: Epidemiology and functional and radiological results in a prospective series of 518 patients at 1year's follow-up

International audienceINTRODUCTION:Recent epidemiological data for spinal trauma in France are sparse. However, increased knowledge of sagittal balance and the development of minimally invasive techniques have greatly improved surgical management.OBJECTIVES:To describe the epidemiology and management of traumatic vertebral fracture, and to analyze evolution and risk factors for poor functional outcome at 1 year's follow-up.MATERIALS AND METHODS:A prospective multicenter French cohort study was performed over a 6-month period in 2011, including all cases of vertebral fracture surgery. Data were collected by online questionnaire over the Internet. Demographic characteristics, lesion type and surgical procedures were collected. Clinical, functional and radiological assessment was carried out at 1 year.RESULTS:Five hundred and eighteen patients, with a mean age of 47 years, were included. Sixty-seven percent of fractures involved the thoracic or lumbar segment. Thirty percent of patients had multiple fractures and 28% neurological impairment. A minimally invasive technique was performed in 20% of cases and neurological decompression in 25%. Dural tear was observed in 42 patients (8%). Seventy percent of patients were followed up at 1 year. Functionally, SF-36 scores decreased on all dimensions, significantly associated with age, persistent neurological deficit and previous spine imbalance. Thirty-eight percent of working patients had returned to work. Radiologically, sagittal balance was good in 74% of cases, with fracture consolidation in 70%.DISCUSSION:Despite progress in management, spinal trauma was still a source of significant morbidity in 2011, with pronounced decrease in quality of life. Conserved sagittal balance appeared to be associated with better functional outcome