First observations of the microvine development under 100 % LED (light emitting diodes) illumination

In order to reduce energy waste for artificial lights and subsequent air conditioning in plant growth chambers, the aim of this preliminary study was to evaluate the feasibility of growing the microvine under 100 % of LED illumination. Plant growth under two different LED lights was compared amongst each other and with plants maintained in greenhouse conditions. Regarding the impact on the reproductive and vegetative systems, the study showed that LED light is suitable to grow microvines in confined environments. Plants exposed to LED light exhibited similar leaf emergence rate but reduced vegetative and reproductive organ size compared to plants grown in the greenhouse. Photosynthesis for plants exposed to LED light was higher than what is usually observed on grapevine under natural conditions.

Impact des protections individuelles à effet de serre sur des plants d'arganier en conditions hydriques non limitantes.

La régénération de la forêt d'arganiers au Maroc est un échec complet, principalement à cause de l'abroutissement par les animaux domestiques. La protection individuelle de chaque jeune arganier par un abri-serre pourrait contribuer à permettre l'installation de nouveaux peuplements, en évitant les conflits entre les éleveurs et les forestiers. La croissance en longueur et en diamètre de jeunes plants d'arganiers, dans des conditions de bonne alimentation hydrique à l'intérieur de ces abris a fait l'objet de ce travail. On compare 4 modalités différentes d'abris à effet de serre, l'abri blanc aéré et l'abri blanc étanche, l'abri sombre aéré et l'abri sombre étanche. Les abris blancs et aérés donnent les meilleurs résultats

Segmentation d'images ultrasonores

- Dans cette étude nous nous intéressons à la segmentation d'images ultrasonores. Nous développons une méthode de segmentation utilisant, d'une façon originale, le modèle de régions actives géodésiques. Cette approche tient compte à la fois des informations contours et régions. Nous exploitons les propriétés statistiques de ces informations. Pour cela l'information région est approchée par un modèle de distribution de niveaux de gris de la région. La recherche des contours est faite par la méthode des ensembles de niveaux à partir d'une courbe initiale. Nous avons testé notre algorithme sur des images ultrasonores réelles, images échotomographiques veineuses in vivo présentant un thrombus que nous cherchons à isoler. Les résultats expérimentaux obtenus illustrent bien les bonnes performances de notre algorithme pour détecter et localiser le thrombus, et montrent aussi que notre méthode est bien adaptée à la segmentation des images ultrasonores

Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis

Background Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy. Methods We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance. Results We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography. Conclusion Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data

Systems medicine and integrated care to combat chronic noncommunicable diseases

We propose an innovative, integrated, cost-effective health system to combat major non-communicable diseases (NCDs), including cardiovascular, chronic respiratory, metabolic, rheumatologic and neurologic disorders and cancers, which together are the predominant health problem of the 21st century. This proposed holistic strategy involves comprehensive patient-centered integrated care and multi-scale, multi-modal and multi-level systems approaches to tackle NCDs as a common group of diseases. Rather than studying each disease individually, it will take into account their intertwined gene-environment, socio-economic interactions and co-morbidities that lead to individual-specific complex phenotypes. It will implement a road map for predictive, preventive, personalized and participatory (P4) medicine based on a robust and extensive knowledge management infrastructure that contains individual patient information. It will be supported by strategic partnerships involving all stakeholders, including general practitioners associated with patient-centered care. This systems medicine strategy, which will take a holistic approach to disease, is designed to allow the results to be used globally, taking into account the needs and specificities of local economies and health systems

Agroforesterie et services écosystémiques en zone tropicale

Respectueux de l’environnement et garantissant une sécurité alimentaire soutenue par la diversification des productions et des revenus qu’ils procurent, les systèmes agroforestiers apparaissent comme un modèle prometteur d’agriculture durable dans les pays du Sud les plus vulnérables aux changements globaux. Cependant, ces systèmes agroforestiers ne peuvent être optimisés qu’à condition de mieux comprendre et de mieux maîtriser les facteurs de leurs productions. L’ouvrage présente un ensemble de connaissances récentes sur les mécanismes biophysiques et socio-économiques qui sous-tendent le fonctionnement et la dynamique des systèmes agroforestiers. Il concerne, d’une part les systèmes agroforestiers à base de cultures pérennes, telles que cacaoyers et caféiers, de régions tropicales humides en Amérique du Sud, en Afrique de l’Est et du Centre, d’autre part les parcs arborés et arbustifs à base de cultures vivrières, principalement de céréales, de la région semi-aride subsaharienne d’Afrique de l’Ouest. Il synthétise les dernières avancées acquises grâce à plusieurs projets associant le Cirad, l’IRD et leurs partenaires du Sud qui ont été conduits entre 2012 et 2016 dans ces régions. L’ensemble de ces projets s’articulent autour des dynamiques des systèmes agroforestiers et des compromis entre les services de production et les autres services socio-écosystémiques que ces systèmes fournissent

Seasonal variation of photosynthetic model parameters and leaf area index from global Fluxnet eddy covariance data

This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/.Global vegetation models require the photosynthetic parameters, maximum carboxylation capacity (V[subscript cm]), and quantum yield (alpha) to parameterize their plant functional types (PFTs). The purpose of this work is to determine how much the scaling of the parameters from leaf to ecosystem level through a seasonally varying leaf area index (LAI) explains the parameter variation within and between PFTs. Using Fluxnet data, we simulate a seasonally variable LAI(F) for a large range of sites, comparable to the LAI[subscript M] derived from MODIS. There are discrepancies when LAI[subscript F] reach zero levels and LAI[subscript M] still provides a small positive value. We find that temperature is the most common constraint for LAI[subecript F] in 55% of the simulations, while global radiation and vapor pressure deficit are the key constraints for 18% and 27% of the simulations, respectively, while large differences in this forcing still exist when looking at specific PFTs. Despite these differences, the annual photosynthesis simulations are comparable when using LAI[subscript F] or LAI[subscript M](r² = 0.89). We investigated further the seasonal variation of ecosystem-scale parameters derived with LAI[subscript F]. V[subscript cm] has the largest seasonal variation. This holds for all vegetation types and climates. The parameter alpha is less variable. By including ecosystem-scale parameter seasonality we can explain a considerable part of the ecosystem-scale parameter variation between PFTs. The remaining unexplained leaf-scale PFT variation still needs further work, including elucidating the precise role of leaf and soil level nitrogen