Effectiveness of upper limb functional electrical stimulation after stroke for the improvement of activities of daily living and motor function: a systematic review and meta-analysis

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. (DOC 60 kb

Bayesian methods for predicting LAI and soil water content

peer reviewedLAI of winter wheat (Triticum aestivum L.) and soil water content of the topsoil (200 mm) and of the subsoil (500 mm) were considered as state variables of a dynamic soil-crop system. This system was assumed to progress according to a Bayesian probabilistic state space model, in which real values of LAI and soil water content were daily introduced in order to correct the model trajectory and reach better future evolution. The chosen crop model was mini STICS which can reduce the computing and execution times while ensuring the robustness of data processing and estimation. To predict simultaneously state variables and model parameters in this non-linear environment, three techniques were used: Extended Kalman Filtering (EKF), Particle Filtering (PF), and Variational Filtering (VF). The significantly improved performance of the VF method when compared to EKF and PF is demonstrated. The variational filter has a low computational complexity and the convergence speed of states and parameters estimation can be adjusted independently. Detailed case studies demonstrated that the root mean square error (RMSE) of the three estimated states (LAI and soil water content of two soil layers) was smaller and that the convergence of all considered parameters was ensured when using VF. Assimilating measurements in a crop model allows accurate prediction of LAI and soil water content at a local scale. As these biophysical properties are key parameters in the crop-plant system characterization, the system has the potential to be used in precision farming to aid farmers and decision makers in developing strategies for site-specific management of inputs, such as fertilizers and water irrigation.Filtering method-based state and parameter estimation for crop model

Inconsistent diagnosis of acute malnutrition by weight-for-height and mid-upper arm circumference : contributors in 16 cross-sectional surveys from South Sudan, the Philippines, Chad, and Bangladesh

Background: The two anthropometric indicators of acute malnutrition in children under 5 years, i.e. a Mid-Upper Arm Circumference < 125 mm (MUAC(125)) or a Weight-for-Height Z-score<-2 (WHZ(-2)), correlate poorly. We aimed at assessing the contribution of age, sex, stunting (Height-for-Age HAZ<-2), and low sitting-standing height ratio Z-score (SSRZ in the 1st tertile of the study population, called hereafter 'longer legs') to this diagnosis discrepancy. Methods: Data from 16 cross-sectional nutritional surveys carried out by Action Against Hunger International in South Sudan, the Philippines, Chad, and Bangladesh fed multilevel, multivariate regression models, with either WHZ -2 or MUAC(125) as the dependent variable and age, sex, stunting, and 'longer legs' as the independent ones. We also compared how the performance of MUAC125 and WHZ-2 to detect slim children, i.e. children with a low Weight-for-Age (WAZ=-2), was modified by the contributors. Results: Overall 23.1 % of the 14,409 children were identified as acutely malnourished by either WHZ-2 or MUAC125, but only 28.5 % of those (949/3,328) were identified by both indicators. Being stunted (+17.8 %; 95 % CI: 14.8 %; 22.8 %), being a female (+16.5 %; 95 % CI: 13.5 %; 19.5 %) and being younger than 24 months (+33.6 %; 95 % CI: 30.4 %; 36.7 %) were factors strongly associated with being detected as malnourished by MUAC125 and not by WHZ-2, whereas having 'longer legs' moderately increased the diagnosis by WHZ-2 (+4.2 %; 95 % CI: 0.7 %; 7.6 %). The sensitivity to detect slim children by MUAC125 was 31.0 % (95 % CI: 26.8 %; 35.2 %) whereas it was 70.6 % (95 % CI: 65.4 %; 75.9 %) for WHZ-2. The sensitivity of MUAC125 was particularly affected by age (57.4 % vs. 18.1 % in children aged = 24 months). Specificity was high for both indicators. Conclusions: MUAC125 should not be used as a stand-alone criterion of acute malnutrition given its strong association with age, sex and stunting, and its low sensitivity to detect slim children. Having 'longer legs' moderately increases the diagnosis of acute malnutrition by WHZ-2. Prospective studies are urgently needed to elucidate the clinical and physiological outcomes of the various anthropometric indicators of malnutrition

Assessing nitrogen fertilisation strategies according to climate variability : A modelling approach

/Suivi en temps réel de l’environnement d’une parcelle agricole par un réseau de micro-capteurs en vue d’optimiser l’apport en engrais azoté

Assessing the potential of an algorithm based on mean climatic data to predict wheat yield

The real-time non-invasive determination of crop biomass and yield prediction is one of the major challenges in agriculture. An interesting approach lies in using process-based crop yield models in combination with real-time monitoring of the input climatic data of these models, but unknown future weather remains the main obstacle to reliable yield prediction. Since accurate weather forecasts can be made only a short time in advance, much information can be derived from analyzing past weather data. This paper presents a methodology that addresses the problem of unknown future weather by using a daily mean climatic database, based exclusively on available past measurements. It involves building climate matrix ensembles, combining different time ranges of projected mean climate data and real measured weather data originating from the historical database or from real-time measurements performed in the field. Used as an input for the STICS crop model, the datasets thus computed were used to perform statistical within-season biomass and yield prediction. This work demonstrated that a reliable predictive delay of 3-4 weeks could be obtained. In combination with a local micrometeorological station that monitors climate data in real-time, the approach also enabled us to (i) predict potential yield at the local level, (ii) detect stress occurrence and (iii) quantify yield loss (or gain) drawing on real monitored climatic conditions of the previous few days.Suivi en temps réel de l’environnement d’une parcelle agricole par un réseau de micro-capteurs en vue d’optimiser l’apport en engrais azoté

Analysis of fine-scale mammalian evolutionary breakpoints provides new insight into their relation to genome organisation

<p>Abstract</p> <p>Background</p> <p>The Intergenic Breakage Model, which is the current model of structural genome evolution, considers that evolutionary rearrangement breakages happen with a uniform propensity along the genome but are selected against in genes, their regulatory regions and in-between. However, a growing body of evidence shows that there exists regions along mammalian genomes that present a high susceptibility to breakage. We reconsidered this question taking advantage of a recently published methodology for the precise detection of rearrangement breakpoints based on pairwise genome comparisons.</p> <p>Results</p> <p>We applied this methodology between the genome of human and those of five sequenced eutherian mammals which allowed us to delineate evolutionary breakpoint regions along the human genome with a finer resolution (median size 26.6 kb) than obtained before. We investigated the distribution of these breakpoints with respect to genome organisation into domains of different activity. In agreement with the Intergenic Breakage Model, we observed that breakpoints are under-represented in genes. Surprisingly however, the density of breakpoints in small intergenes (1 per Mb) appears significantly higher than in gene deserts (0.1 per Mb).</p> <p>More generally, we found a heterogeneous distribution of breakpoints that follows the organisation of the genome into isochores (breakpoints are more frequent in GC-rich regions). We then discuss the hypothesis that regions with an enhanced susceptibility to breakage correspond to regions of high transcriptional activity and replication initiation.</p> <p>Conclusion</p> <p>We propose a model to describe the heterogeneous distribution of evolutionary breakpoints along human chromosomes that combines natural selection and a mutational bias linked to local open chromatin state.</p

Yield variability linked to climate uncertainty and nitrogen fertilisation

peer reviewedAt the parcel scale, crop models such as STICS are powerful tools to study the effects of variable inputs such as management practices (e.g. nitrogen (N) fertilisation). In combination with a weather generator, we built up a general methodology that allows studying the yield variability linked to climate uncertainty, in order to assess the best N practice. Our study highlighted that, applying the Belgian farmer current N practice (60-60-60 kg N/ha), the yield distribution was found to be very asymmetric with a skewness of -1.02 and a difference of 5% between the mean (10.5 t/ha) and the median (11.05 t/ha) of the distribution. This implies that, under such practice, the probability for farmers to achieve decent yields, in comparison to the mean of the distribution, was the highest.Suivi en temps réel de l’environnement d’une parcelle agricole par un réseau de micro-capteurs en vue d’optimiser l’apport en engrais azoté

Comportement mécanique à haute température des aciers martensitiques revenus pour application aux réacteurs à neutrons rapides

National audienceLa conception du futur réacteur à neutrons rapides à caloporteur sodium (SFR) a motivé de nombreuses études sur le comportement en fatigue, fluage et fatigue-fluage à haute température d'aciers martensitiques revenus (450-600°C). Depuis les années 80, l'instab ilité de leur microstructure dans certaines conditions de chargement (fatigue, fluage) a été mise en évidence dans la littérature. Cette instabilité conduit à un adoucissement qu'il convient de comprendre et de prédire. Nous avons particulièrement étudié l'effet des chargements caractéristiques des conditions en service auxquelles seront soumis les composants du réacteur SFR (faibles amplitudes de déformation cycliques, longues durées de vie en fluage), pour lesquelles les données expérimentales sont rares. Des évolutions microstructurales et un adoucissement notable ont été mis en évidence dans ces conditions. Des modèles micromécaniques basés sur les densités de dislocations continus permettent de prédire qualitativement un grand nombre des phénomènes observés

Propriétés en fluage à haute température et caractérisations microstructurales des joints soudés P92

National audienceLa présente étude est consacrée aux propriétés en fluage des liaisons soudées en acier P92. Les objectifs sont de déterminer le lieu de rupture d'éprouvettes sollicitées en fluage à 550°C sous diffé rents niveaux de contraintes (160 à 240 MPa) et de caractériser l'évolution de la microstructure du joint soudé au cours du fluage à cette même température. L'observation des faciès de rupture et l'examen des microstructures du joint soudé avant et après fluage sont entrepris afin de caractériser le mode d'endommagement. Pour les éprouvettes observées, la rupture est ductile et se produit dans la zone affectée thermiquement, en particulier dans la zone intercritique. Une striction importante est également observée, à l'intérieur de laquelle sont présentes de multiples cavités et fissures