Moderate Growth Time Series for Dynamic Combinatorics Modelisation

Here, we present a family of time series with a simple growth constraint. This family can be the basis of a model to apply to emerging computation in business and micro-economy where global functions can be expressed from local rules. We explicit a double statistics on these series which allows to establish a one-to-one correspondence between three other ballot-like strunctures

Phytoconstituents of leaf extracts of Ziziphus jujuba Mill. plants harvested in Tunisia

The present study aimed to determine the phytoconstituent compositions of the leaves of four Ziziphus jujuba ecotypes (Choutrana, Mahdia, Mahres and Sfax). The chromatographic peaks of 18 compounds, including nine major fatty acids, five sterols, two triterpene alcohols and two methysterols, were quantified by the capillary gaseous chromatography method. The major fatty acids identified were linolenic (42.04%) and palmitic (23.04%). Unsaturated fatty acids ranged between 53% and 60%. The predominant sterols (mg/100g) were β-sitosterol (40.36) and stigmasterol (24.18). Cycloartenol (68.55mg/100g) and citrostadienol (12.27mg/100g) were the major metylsterols. Methylene cycloartanol ranged between 1.2mg/100g (Sfax) and 1.5mg/100g (Mahdia). Total phenolic content measured by Folin-ciocalteux ranged from 3.97mg GAE/g to 6.04mg GAE/g. The predominant flavonoids identified by HPLC were apigenin (6.1mg/g) and rutin (1.91mg/g). The fatty acids and flavonoids in the Z. jujuba leaves were responsible for their therapeutic and pharmaceutical effects. This could explain why Tunisian people traditionally use it as medicine to treat several pathologies

Changes of non‐affected upper limb cortical representation in paraplegic patients as assessed by fMRI

Peripheral and central nervous system lesions can induce reorganization within central somatosensory and motor body representations. We report changes in brain activation patterns during movements of non‐affected body parts in paraplegic patients with spinal cord injury (SCI). Nine SCI patients and 12 healthy controls underwent blood oxygen level dependent signal functional MRI during sequential finger‐to‐thumb opposition, flexion and extension of wrist and of elbow, and horizontal movements of the tongue. Single subject and group analyses were performed, and the activation volumes, maximum t values and centres of gravity were calculated. The somatotopical upper limb and tongue representations in the contralateral primary motor cortex (M1) in the SCI patients were preserved without any shift of activation towards the deefferented and deafferented M1 foot area. During finger movements, however, the SCI patients showed an increased volume in M1 activation. Increased activation was also found in non‐primary motor and parietal areas, as well as in the cerebellum during movements of the fingers, wrist and elbow, whereas no changes were present during tongue movements. These results document that, in paraplegic patients, the representation of the non‐impaired upper limb muscles is modified, though without any topographical reorganization in M1. The extensive changes in primary and non‐primary motor areas, and in subcortical regions demonstrate that even distant neuronal damage has impact upon the activation of the whole sensorimotor syste

Is "bio-economic" farm modelling of any help for farming system design?

T4. What’s new with bioeconomic models for the analysis and design of agricultural systems?International audienceMany innovations at cropping system level impact the whole farm system by changing the flow of farm resources across farm activities. Using farm models has increasingly been proposed for assessing the feasibility of prototypes of cropping systems at farm level, and evaluating their impacts on household food production, farm income, and the environment. Such models are often called bio-economic model as a way to stress the mixing of knowledge about the biophysical and economic aspects of farming (Janssen & van Ittersum, 2007; Thornton & Herrero, 2001). A priori, one should not expect accurate predictions from these coupled bio-economic models, because of their complexity and the difficulty of measuring certain key input variables, such as labour availability for the different farm and off-farm activities, family income, and intra-farm consumption of agricultural products. This type of models can rather be used to explore ‘what if’ scenarios and to understand their outcomes including their inevitable uncertainty. In this paper, we review our experience with bio-economic farm models as virtual test benches for evaluating “cropping systems ideotypes” (CSI), i.e. idealized cropping systems proposed as alternatives to existing cropping systems, for increasing farm income and production or for reducing negative impacts of farming on the environment. Six published case studies are used. The objective is to examine to what extent the models developed fulfilled their purpose of evaluating prototypes of cropping systems for farming systems design

Modèle statistique de solution binaire de sels fondus du type AB

La description en « ion entouré » d’une solution binaire de sels fondus comportant des ions de valence différente nous a permis à l’aide du traitement statistique de Bragg et Williams, et en donnant aux variations d’énergie potentielle des formes linéaires ou paraboliques, de retrouver des modèles connus de solution

Influence d'un effet d'ordre sur les grandeurs thermodynamiques de mélange de systèmes dissymétriques de sels fondus AB

Une description statistique de la configuration d'un système binaire dissymétrique AB2 — A'B permet d'exprimer la fonction de partition de la solution. Des hypothèses énergétiques simples, jointes à la prise en compte d'un effet d'ordre analogue à celui du modèle quasi-chimique de Guggenheim, conduisent à l'évaluation statistique de cette fonction ainsi que de celles des grandeurs thermodynamiques de la solution.Un traitement numérique, utilisant seulement deux paramètres déduits du comportement limite des solutions diluées, permet une représentation satisfaisante des grandeurs thermodynamiques de systèmes où existe un effet d'ordre appréciable.Des exemples d'application à l'enthalpie de mélange sont donnés pour 30 systèmes de sels fondus dissymétriques