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This paper presents the hazard mapping of groundwater in the Tlemcen urban area (TUA). First, we identified the potential pollution sources (of industrial, agricultural and urban origins) existing in the studied area that can affect the karstic groundwater. It is the most important reserve and the main source of drinking water supply of this area. Then, we mapped all these hazards on a topographic map at scale 1:25,000. Finally, a classified hazard map was established. This investigation clearly shows that the groundwater of TUA is far from being safe from the risk of pollution. Adequate and urgent actions must be taken in order to eliminate or to reduce the risks of contamination of this water resource which is highly vulnerable because of the lack of protection perimeters.

Lightweight yet precise, temperature control protocols are critical in a variety of applications. This is especially true in space where weight and volume are at a premium and reliability is paramount. In space, complex processes to manage the heat fluxes generated from within and absorbed from space by the spacecraft are usually implemented. Surfaces having different heat fluxes might need to be controlled separately and maintained at different temperatures. The work presented in this paper evaluates a novel laser surface modification process to form micro-column arrays (MCA) on any material for use as highly adaptive radiators. The MCA-structured surfaces have experimentally been shown to have excellent emissive properties. Finite element methods have been used to simulate the temperature profiles for surfaces with and without MCA compared to pin fin structures as a function of input heat flux density. In the case of Ti, our models show that pin fin arrays are better heat radiating surfaces than equivalent MCA structures with cone-like profiles. Such structures, however, are difficult to modify and usually require complicated and expensive fabrication processes. Overall, MCA structures are shown to allow good control over base surface temperature for varying heat fluxes and different MCA aspect ratios. For Ti, under steady state conditions, an aspect ratio of 12 has been shown to be optimal for surface heat reduction. Preliminary experimental results show that the temperature drop is inline with that theoretically predicted.

A conformational search of the flexible 2-hedroxyethyl methacrylate molecule by semi-empirical AM1 and B3LYP formalisms leads to six stable conformations. Four of them are in the s-trans conformation. The optimized geometries at DFT using 6-311+G(∗∗) basis set are in good agreement with experimental electron diffraction data of the methyl methacrylate molecule, thereby the s-trans is the most stable form. The harmonic frequencies at the fully optimized geometries of all conformers have been performed at the DFT//B3LYP/6-311+G(∗∗) level of theory. Infrared and Raman intensities and potential energy distributions of the scaled harmonic frequencies are used for the assignment of the observed IR and Raman bands. We noticed a good agreement between the experimental and the computed spectra. The strong band at 1081 cm(-1), in the infrared spectrum, maybe used as a characteristic band of the s-trans conformation. Henceforth, the less stable structure contribute alone for reproducing the Raman bands located at 276 (sh) and 3020 (vw) cm(-1).

2-Hydroxyethyl acrylate is generally used with other acrylic and methacrylic products in order to get the desired characteristics of the final product. In this work we are about to make an assignment of experimental infrared bands with the help of a theoretical quantum chemistry calculations. The exact knowledge of some bands which are not characteristics of acrylic materials will enable us to make a quick analysis with available techniques of low costs for mixtures of polymers based on acrylate and methacrylate molecules. In the experimental part, the infrared spectrum of 2-hydroxyethyl acrylate is obtained by using a FTIR Perkin Elmer model 2000. In the computational part and as first step, the theoretical calculations are performed by the semi-empirical AM1 method for excluding similar structures of 2-hydroxyethyl acrylate molecule by a meticulous conformational analysis. As a second step the obtained structures are optimized using DFT. The simulated frequencies are then scaled and a tentative assignment is made based on band intensities and PED percentages. The theoretical calculations predict the existence of thirteen conformations two of them represent the majority of experimental bands in the infrared spectrum. Two neighbor experimental bands located at 1301 and 1207 cm−1 maybe used as characteristic bands to locate and distinguish the existence of one or both conformations.

Introduction et but de l’etude Les patients victimes d’accidents vasculaires cerebraux (AVC) sont souvent âges, avec des facteurs de risque cardiovasculaires et a risque de denutrition. Le type, la localisation de l’AVC ainsi que les incapacites qui en resultent influencent egalement le pronostic nutritionnel. Ces particularites de terrain et de pathologies necessitent une evaluation initiale puis reiteree tout au long du suivi medical. La prise en charge de l’AVC est bien codifiee mais il existe tres peu de recommandations concernant la prise en charge de la denutrition du sujet en post-AVC et aucun consensus. L’objectif principal de notre travail est de proposer une conduite a tenir pour la prise en charge nutritionnelle afin d’ameliorer le statut nutritionnel de ces patients, et de faciliter la prise en charge en soins de suite et de readaptation. Materiel et methodes L’algorithme realise par notre equipe est base sur notre experience chartraine et sur l’analyse systematique de la litterature. Cette revue de la litterature a ete realisee via PubMed et selon la collaboration Cochrane. Resultats Cet algorithme propose une conduite a tenir des l’admission du patient en service de neurologie et presente les differentes techniques d’assistance nutritionnelle envisageables selon l’evolution du patient. Chaque etape est justifiee par des references bibliographiques et les praticiens referents a contacter sont identifies afin de faciliter la coordination et la rapidite des soins. Ainsi, l’evaluation nutritionnelle precoce par une equipe paramedicale permet de depister les sujets a risque et de mettre en place les premiers supports nutritionnels. Contrairement a ce qui est realise pour des sujets plus jeunes, la nutrition parenterale (voie veineuse centrale ou peripherique) est envisagee precocement. Elle permet une supplementation nutritionnelle rapide et offre une voie d’abord pour d’autres therapeutiques. Elle apporte un delai de reflexion et d’evaluation au clinicien. Les conditions et modalites de pose de la SNG sont clairement indiquees. La mise en place d’une gastrostomie intestinale (per-endo) est evaluee par une equipe multidisciplinaire avec le patient et sa famille afin d’en faciliter la tolerance et d’ameliorer son efficacite. Elle facilite la prise en charge en soins de suite. Conclusion Ces propositions devraient faciliter l’evaluation des troubles de la deglutition et la prevention de la denutrition. Ce guide a pour but d’eviter les complications telles que la pneumopathie d’inhalation, la denutrition ou la deshydratation qui sont particulierement rapides chez les sujets âges ayant ete atteints d’un AVC. Un premier objectif est de verifier si cet algorithme previendrait la malnutrition, eviterait les fausses routes et n’aurait pas d’effets secondaires. Un objectif ulterieur serait de mener une etude comparant le statut nutritionnel de nos patients a ceux d’autres equipes.