The knowledges of traditional irrigation in the oasis of Kerzaz in southwest Algerian: Legacy and development

In the valley of Saoura, the demand for water for irrigation has increased significantly and rapidly, it requires mobilization and rational and intensive use of all existing water sources like the groundwater which are the only source of drinking water supply and irrigation in the region and the protection of the large vein that feeds the Saoura and bearing his name "oued Saoura". Oasis Kerzaz is amongst the the most celebrated oasis and the biggest of valley of Saoura , it now suffers from several impediments to their development as: the scarcity of irrigation water, land abandonment, the silting up, the chunking and the exiguity of agricultural land, the food nature of agricultural activity and incurable diseases of crops.Keywords: palm grove; well; Chadouf; Khottara; motorpump; Saoura

The fate of water in the oasis of Ouakda between traditional systems and modern (Region of Béchar, Southwest, Algeria)

One of the subjects that touch the field of environment is undoubtedly the traditional catchment systems and drainage divide in the oasis. The ancestral techniques such as wells chadouf, quanat, Khettara and foggaras have protected the oasis and the man in the past. These techniques were used in an arid middle by the oasis dwellers and resisted to a hostile climate for centuries. In spite of the low rainfall in the region of our oasis, the oasis dwellers of Ouakda through their intelligence, they were able to cultivate their land without disturbing a fragile ecosystem through exploitation of groundwater table thanks to the use of foggaras with the small distance which does not exceed 100 m. But the intervention of modern systems of water catchment like deep boreholes which overexploiting nonrenewable tablecloths and the pumps large capacity, the man has completely destroyed a clean environment. Today, thanks to these pumping, the groundwater level has dropped considerably; soil salinity is remarkable on all the parcels of the old palm grove and the Oued. We try in this Article to study the history of traditional techniques of water catchments in the oasis of Ouakda, to do a comparison between the ancestral systems used in the another oasis in this oasis, to study the impact of the motor pumps on the degradation of traditional systems and detrimental effects (Soil salinity and the phenomenon of lowering of the groundwater) after the use of modern techniques of water catchment.Keywords: Oasis, Ouakda, Foggara, Wells, Chadouf, motor pump

THE ORIGINALITY OF OASIS OF SAOURA IN SOUTH-WEST OF ALGERIA

For centuries the oases of the Saoura continue to manage critical situations of drought and the hostility of the Algerian Sahara through the rational exploitation of water, a rare and precious source of traditional irrigation techniques have proved their efficiency. The use of new groundwater drainage systems of drilling, and the lack of effective management of the Foggaras, has made this system lose its value, deteriorate and let the palm groves disappear. More than 80% of these systems have been abandoned in recent years. With increasing urbanization, population growth, climate change and the uncontrolled proliferation of motor pumps, the level of the water table is lowered and the quality of the water is degraded. The foggaras have gradually been abandoned, which leads to the degradation of the gardens and the old oasis

Characterization of Ga1−x\mathsf{_{1-x}}Inx\mathsf{_x}Sb thin layers grown on GaAs substrate by infrared reflectivity

Infrared reflectivity measurement are made on Ga$_{0.70}$In$_{0.30}$Sb thin layers grown on semi-insulating GaAs substrate with free-carrier density varying from 10$^{17}$ cm$^{-3}$ to 10$^{18}$ cm$^{-3}$. Electrical and optical parameters of the layers are determined simultaneously by fitting appropriate theoretical model with experimental data. Densities and mobilities obtained are of the order of the ones given by Hall measurements and optical parameters are in good agreement with those given in the literature.Des mesures de réflectivité infra-rouge sont faites sur des couches de Ga$_{0,70}$In$_{0,30}$Sb épitaxiées sur substrat de GaAs semi-isolant avec une densité de porteurs allant de 10$^{17}$ cm$^{-3}$ à 10$^{18}$ cm$^{-3}$. Les paramètres électriques et optiques de la couche sont déterminés simultanément en ajustant les données expérimentales par le modèle théorique approprié. Les densités et mobilités obtenues sont comparables à celles données par les mesures d'effet Hall, et les paramètres optiques sont en bon accord avec les valeurs données dans la littérature

Spectral responses in near-infrared of the mixed compounds III-V, ternary and quaternary, based on GaSb

From the simulation of the spectral response of the different photodetector devices elaborated in our laboratory (C.E.M.), we determine the influence of geometrical and physical parameters in order to achieve the best photodetector operating at the wavelength 2.55 $\mu$m. In this paper we present: Gao$_{0.6}$In$_{0.4}$Sb$_{\rm n}$/Ga$_{0.6}$In$_{0.4}$Sb$_{\rm p}$ homojunctions matched on GaSb$_{\rm p}$ substrate, Ga$_{0.75}$In$_{0.25}$As$_{0.23}$Sb$_{\rm p}$/GaSb$_{\rm n}$ ternary heterojunction and GaSb$_{\rm p}$/Ga$_{0.74}$In$_{0.26}$As$_{0.23}$Sb$_{\rm 0.77p}$/GaSb$_{\rm n}$ quaternary heterojunction. The GaSb$_{\rm p}$ layer with an energy band gap greater than Ga$_{0.74}$In$_{0.26}$As$_{0.23}$Sb$_{\rm 0.77p}$ optical gap will act as a window, reducing the effect of surface recombinaison. Results of the simulation are compared to experimental curves to determine the values of photoelectrical parameters (diffusion length, recombination velocity at the surface ...).Les mesures de réponse spectrale dans la gamme [0,4 eV à 2 eV] ont été effectuées sur des homojonctions, Ga$_{0,6}$In$_{0,4}$Sb$_{\rm n}$/Ga$_{0,6}$In$_{0,4}$Sb$_{\rm p}$ déposées sur un substrat de GaSb et des hétérostructures ternaires Ga$_{0,75}$In$_{0,25}$Sb$_{\rm p}$/GaSb$_{\rm n}$ et quaternaires GaSb$_{\rm p}$/Ga$_{0,74}$In$_{0,26}$As$_{0,23}$Sb$_{\rm 0,77p}$/GaSb$_{\rm n}$. La couche de GaSbp avec un gap plus grand que celui de Ga$_{0,74}$In$_{0,26}$As$_{0,23}$Sb$_{\rm 0,77p}$ joue le rôle d'effet fenêtre. En s'appuyant sur les résultats de la simulation et en accordant les spectres expérimentaux aux spectres théoriques, on détermine les valeurs des paramètres photoélectriques (longueurs de diffusion, les vitesses de recombinaison en surface ... ) intervenant dans le rendement quantique

Contact force computation based on BSIPs

International audienceno abstrac

Âge au diagnostic de trouble du spectre autistique en fonction de l’appartenance à une minorité ethnoculturelle ou du statut migratoire, une revue de la littérature systématisée

International audienceIntroduction: The early identification and access to health care of toddlers with autism spectrum disorder (ASD) - or at risk of developing it - is a crucial public health issue, as care and intervention may be more effective in younger children in order to improve their development and prognosis. However, there are still disparities in identification and health care access for children with ASD despite better screening methods. Given that misdiagnosis and delayed diagnosis are often due to the cultural gap between clinician and patient in some psychiatric disorders such as depression or schizophrenia, we examined this question concerning ASD and wondered to what extent ethno-cultural or migratory status might have an impact on the age at which a child is diagnosed. The only published review looking for independent factors influencing age of diagnosis concludes that the factors that have been proved to play a role are: socioeconomic status; symptom severity; level of parental concern, and family interactions with the health and education systems prior to diagnosis. The impact of ethno-cultural or migratory status is less clear. And yet, all these factors may be interconnected: migrants have on average a lower socioeconomic status, minorities don't have the same access to health care, and cultural background can have an influence on what is expected of a child's development and health. In order to try and clarify this issue and to analyze the way in which the international literature approaches the subject, we carried out a systematic review.Method: Six databases were interrogated: Pubmed, Embase, Psychinfo, WebOfScience, Cochrane and Cinahl using the key words "ASD", "pervasive developmental disorder", "diagnosis", "age", "migrant", "ethnicity", "cross cultural". We narrowed neither the period of time not selected the articles by their method, as our objective was to collect the entirety of the articles written on the subject. We completed this review by including the pertinent references made in the articles.Results: Twenty articles were included, all epidemiological and observational, about children diagnosed in specialized centers. Published between 2002 and 2019, they cover a 20-year research period, between 1992 and 2016. The methods are disparate: the diagnosis criteria used are from DSM IV, IV TR and ICD; data originate from medical records, phone or internet surveys, and Medicaid healthcare claims. Comparison of the age at diagnosis is the principal objective for only thirteen studies; statistical data analyses vary, especially concerning adjustments. Seventy-five percent of the articles originate from North America where the compared populations are defined by ethnic and racial categories that are not used in some other countries, notably in Europe. Only five explore the link between migratory status and age at diagnosis. The research results concerning the impact of ethnicity are contradictory, while those concerning migratory status seem to indicate that migrant children are likely to be diagnosed later. But the articles and their methods being too heterogeneous, it was difficult to make a meta-analysis and impossible to reach a scientific conclusion.Conclusion: Nevertheless, this review highlights the existence of a lot of confounding factors and raises many issues. It shows that the United States produces most of the studies whose conclusions cannot be generalized because of the particular history and organization of this country. In Europe, where belonging to minority groups is thought to be through migratory status, studies are rare. There is an urgent need for new research in order to clarify the connection between migratory status and socioeconomic factors, to precisely define the independent variables influencing diagnosis -such as access to healthcare- and finally to explore the possibility of different symptomatic expressions depending on cultural backgrounds. This review falls within studies currently carried out by the psychiatric service at Avicenne hospital in Bobigny, France about ASD in a transcultural context

Velocity-dependent changes of rotational axes in the non-visual control of unconstrained 3D arm motions.

International audienceWe examined the roles of inertial (e(3)), shoulder-centre of mass (SH-CM) and shoulder-elbow articular (SH-EL) rotation axes in the non-visual control of unconstrained 3D arm rotations. Subjects rotated the arm in elbow configurations that yielded either a constant or variable separation between these axes. We hypothesized that increasing the motion frequency and the task complexity would result in the limbs' rotational axis to correspond to e(3) in order to minimize rotational resistances. Results showed two velocity-dependent profiles wherein the rotation axis coincided with the SH-EL axis for S and I velocities and then in the F velocity shifted to either a SH-CM/e(3) trade-off axis for one profile, or to no preferential axis for the other. A third profile was velocity-independent, with the SH-CM/e(3) trade-off axis being adopted. Our results are the first to provide evidence that the rotational axis of a multi-articulated limb may change from a geometrical axis of rotation to a mass or inertia based axis as motion frequency increases. These findings are discussed within the framework of the minimum inertia tensor model (MIT), which shows that rotations about e(3) reduce the amount of joint muscle torque that must be produced by employing the interaction torque to assist movement