September | VOLUME 2 | ISSUE 9 | 2016 | http://american-jiras.com/September_2016.html/ http://american-jiras.com/Abstract1_916.html RESUMEContexte: L'optique géométrique est une discipline qui a interpellée beaucoup des chercheurs, car il a été montré que dans ce domaine en particulier, les apprenants de tous les niveaux scolaires (du primaire voire la maternelle à l'université) ont des difficultés à comprendre la nature complexe des concepts et notions et à cerner leur mise en pratique. Objectifs: Cette recherche vise à localiser les sources des difficultés rencontrées par certains étudiants de première année baccalauréat sciences expérimental en optique géométrique. Méthodes: Nous avons utilisé trois méthodes d'analyse bien connus : Groupes de discussion, la Technique du Groupe Nominal (TGN) et le Questionnaire crayon/papier Résultats: Les données obtenues ont permis de constater, d'une part que les prérequis sont surestimés, car les notions apprises dans le cycle collégial sont oubliées et d'autre part que la notion de « trajectoire de rayon lumineux », notion basique en optique géométrique, semble présenter des difficultés pour ces apprenants. Conclusions: les résultats du questionnaire et la TGN et Groupes de discussion sont similaires et complémentaires. Il devient clair que l'utilisation de la TGN et Groupes de discussion et le questionnaire sont des outils efficaces pour diagnostiquer les difficultés et obstacles des élèves du secondaire en optique géométrique. Donc, la TGN et groupes de discussion peut être utilisés non seulement pour identifier les problèmes des élèves avec des notions scientifiques en optique géométrique, mais aussi dans d'autres matières.Mots-clés: la Technique du groupe nominal TGN, groupes de discussion, optique géométrique, physique, Questionnaire.ABSTRACTBackground: The geometric optics is a discipline that has challenged many researchers because it has been shown that in this particular area, learners of all school levels (elementary or kindergarten to university) have difficult to understanding the complex nature of concepts and ideas and identify their implementation. Objectives: This research aims to locate the sources of the difficulties in geometrical optics in a group baccalaureate experimental sciences. Methods: We used three well-known methods of analysis Focus Group, the Nominal Group Technique (NGT) and the questionnaire. Results: The obtained data have shown, firstly that the prerequisites are overstated because the concepts learned in the college cycle are forgotten and further that the concept of 'light beam path' concept in basic geometric optics, seems to present difficulties for these learners. Conclusions: The results of the questionnaire and the NGT and Focus Group are similar and complementary. It becomes clear that the use of the NGT and Focus groups and questionnaire are effective tools to diagnose the difficulties and obstacles of high school students in geometrical optics. So the NGT and discussion groups can be used not only to identify the problems of students with scientific concepts in geometrical optics, but also in other subjects.Keywords: the Nominal Group Technique, Focus Group, Geometrical optics, physics, Questionnaire. http://american-jiras.com/Abstract2_916.html RESUMEIntroduction : Les troubles de comportements alimentaires (TCA) sont des problèmes de santé fréquents chez les adolescents. Objectif : Estimer la prévalence des TCA chez les adolescents et identifier les facteurs associés à ces troubles. Méthodologie : Etude transversale portant sur un échantillon de 367 élèves des collèges et des lycées privés et publiques. Un auto-questionnaire sur les caractères sociodémographiques et sur les habitudes de vie et alimentaires a été administré. Le dépistage de TCA s'est fait grâce à une échelle spécifique Eating Attitudes Test (EAT-26) Des mesures anthropométriques ont été réalisées de manière standard chez tous les adolescents. Résultats : L'âge moyen était de 15,58 ± 2,01 avec un minimum de 12 et un maximum de 19 ans. L'indice de masse corporelle (IMC) moyen était de 19,99 ± 2,47 kg/m2. 51,5% étaient des filles. La prévalence de TCA était de 22.6%, cette prévalence est plus importante chez les filles par rapport aux garçons (28,1% Vs 16,6%, p<0,007). Dans l'échantillon, parmi les adolescents ayant un TCA, 53% expriment des attitudes et des comportements inadaptés face à l'alimentation, 22% ont peur de prendre du poids, 33,1% désirent en perdre et 30,1% ont des préoccupations par rapport à leur image corporelle. Concernant les facteurs socioculturels, 31,4% essayent d'être comme les personnes parues à la télé ou dans des magasins, 25,5% déclarent entendre des commentaires par rapport à leur apparence physique, 29,1% tentent de changer leur poids pour éviter les moqueries, et 34,8% mentionnent entretenir de mauvaises relations avec leurs amis. Le régime alimentaire était le moyen de contrôle de poids le plus utilisé chez les adolescents ayant un TCA (32,4%, p<0,01). Conclusion : Les troubles de comportement alimentaire sont des problèmes de santé fréquents dans notre contexte, d'où la nécessité d'entreprendre des mesures préventives de cette pathologie.Mots clés : Adolescents, troubles de comportements alimentaires, prévalence, Fès.ABSTRACTBackground: the eating disorders (TCA) are frequent health problems among adolescents. Objective: To estimate the prevalence of TCA in adolescents and identify the risk factors associated with these disorders. Methods: Cross-sectional study on a sample of 367 students from colleges and high schools public and private. A self -questionnaire on socio-demographic characteristics and lifestyle and food was administered. The screening of TCA was made thanks to a specific scale Test Eating Attitudes (EAT-26). The anthropometric measures were realized as standard in all adolescents. Results: The average age was 15.58 ± 2.01 with a minimum of 12 and a maximum of 19 years. Body mass index (BMI) average was 19.99 ± 2.47. 51.5% were girls, the prevalence was 22.6% TCA, this prevalence is higher among girls than boys (28,1% vs 16,6%, p <0.007). In the sample, the adolescents having a TCA, 53% expressed concerns towards food, 22% were afraid of gaining weight, 33,1% still want to lose weight and 30,1% had body image reoccupations. Concerning factors sociocultural, 31,4 % try to be as the people appeared on TV or in the magazines, 25,5 % declare to hear comments with regard to their physical appearance, 29,1 % try to change their weight to avoid the mockeries, and 34,8 % mention maintaining bad relations with their friends. The diet was the means of weight control most used among adolescents with a TCA (32,4%, p<0,01). Conclusion: The eating disorders (TCA) are a frequent public health problem in our context, where from the necessity of undertaking preventive measures of this pathology.Keywords: Adolescents, prevalence, eating disorders, Fez. http://american-jiras.com/Abstract3_916.html ABSTRACTBackground: Groundwater contamination may be localized or spread over a large area, depending on the nature and source of the pollutant and on the nature of the groundwater system. A problem of growing concern is the cumulative impact of contamination of a regional aquifer from nonpoint sources and point sources. For the regional level investigation, geoelectrical methods are emerging advance technological supports to identify the contamination hotspot in groundwater. The geoelectrical methods integrated with the sediments chemistry and hydrogeological conditions can be used to investigate groundwater and vadose zone contamination investigation. Objective: The aim of this study is to investigate the aquifer contamination hotspot using advance geophysical techniques. Materials and Methods: In this study we have performed three level of sounding in study area at different geophysical level. The resistivity meter was installed at different AB/2 values to measure the resistivity of the geological formation using different sounding configuration. Parallel to sounding, the hydro-geological parameters were investigated and plotted in same scale. The measured resistivity of all three sounding was applied to hydro-geological formation to prepare the vulnerability maps. Results: The results of this study indicated the different level of the contamination in study aquifer and present in the vulnerability maps. The extension of the contamination was also indicated in the prepared vulnerability map to identify the area or zone of contamination hotspots. Conclusions: The investigation gives the understanding of the aquifer configuration at regional levels as well as the hotspots of contamination. On the basis of aquifer configuration and contamination level, the management's strategy of the groundwater development and managements becomes the cost effective and more efficient technological supports to sustainable developments of water resources. Keywords: Groundwater, Electrical Sounding, Aquifers, vulnerability Map, Sustainable Developments. http://american-jiras.com/Abstract4_916.html ABSTRACTBackground-The increasing use of coal as an energy source, the management of the resulting fly ash and the environmental issues and impacts of the trace elements released from coal combustion have become a great concern to life preservation and sustainability. Objectives-The objective is to chemically, geochemically and mineralogically characterise coals from two contrasting environments (Nigeria and South Africa) including fly ash from a South African coal combustion plant and the data obtained were used to elucidate similarities and differences between the studied coals. Methods- Moisture content, volatile matter, ash content and the Ultimate analysis of the samples were investigated. A comparative chemical analysis of South African Coal (SAC), Nigerian Coal (NGC) and the fly ash from SAC samples were individually investigated using these techniques: X-ray Fluorescence (XRF), Laser Ablation-Inductively Coupled Plasma Mass Spectroscopy (LA-ICPMS) and Fourier Transform Infra-Red Spectroscopy (FTIR). Results-The bulk chemical composition as determined by XRF showed high concentrations of SiO2, Al2O3 in both SAC and NGC samples. The major oxides identified for the electric precipitated fly ash includes SiO2, Al2O3, CaO, Fe2O3, MgO and TiO2. Thirty seven (37) trace elements were analysed for in the samples with varying concentrations from 0 to over 100 mg/Kg. The SAC samples with concentrations greater than 100 mg/Kg in the SAC were Ba, Sr and As; and for NGC; As, Co, Zr, and W were identified. The trace elements in the fly ash which showed concentrations greater than 100 mg/Kg includes Ba, Ce, Sr, Zr, Cr and V. Enrichment of Co, Cr, Ni, Pb, Sb, Zn, U, Th and V was observed in the SAC fly ash analysed when compared with the source SAC sample, attesting to the relative higher relative densities of the metals. Conclusions-The SAC and NGC coals samples used in this study can be classified as medium volatile bituminous coal and a comparably low percentage ash was generated for the NGC and SAC samples. There is an indication of negligible amounts of sulphur in the samples.Keywords: Nigerian coal, South African coal, Coal fly ash, Major oxides, Trace elements, Mineralogy. http://american-jiras.com/Abstract5_916.html Résumé Contexte: Un enseignement/apprentissage efficace dépend fortement de l'identification des obstacles chez l'apprenant. En fait, diagnostiquer les difficultés permet d'approcher l'univers conceptuel des élèves et appréhender leur degré d'acquisition et d'intégration des concepts d'une discipline et ainsi agir en conséquence. La plupart des études ont montrent que Les difficultés et les obstacles d'apprentissages de mécanique sont multiples. Objectifs: Cette recherche vise à localiser les sources des difficultés rencontrées par certains étudiants de deuxième année du baccalauréat en mécanique. Méthodes: Nous avons utilisé trois méthodes d'analyse bien connus : La méthode Delphi , la Technique du groupe nominal et le Questionnaire crayon/papier Résultats: Les données obtenues ont montré que les conditions préalables sont surestimés bien que les étudiants ont déjà appris au cours de la mécanique dans les programmes au cours de tronc commun et la première année de baccalauréat, ils ont encore des difficultés dans l'assimilation des notions de base sur ce sujet. Conclusions: les résultats du questionnaire et le Technique du Groupe Nominale (TGN) et la méthode Delphi  sont similaires et complémentaires. Il devient clair que l'utilisation de TGN et la méthode Delphi  et le questionnaire sont des outils efficaces pour diagnostiquer les difficultés et obstacles des élèves du secondaire en mécanique. Donc, TGN et la méthode Delphi  peut être utilisés non seulement pour identifier les problèmes des élèves avec des notions scientifiques en mécanique, mais aussi dans d'autres matières.Mots-clés: la Technique du groupe nominal TGN, la méthode Delphi , mécanique classique, physique, Questionnaire.AbstractBackground: A teaching / learning effective depends strongly on identifying obstacles in the learner. In fact, diagnose problems can approach the conceptual universe of students and understand their degree of acquisition and integration of the concepts of a discipline and thus act accordingly. Most studies show that the difficulties and obstacles of mechanical learning are manifold. Objectives: This research aims to locate the sources of the difficulties experienced by some students of second year of the Bachelor of Mechanical by using new techniques ( ) firtly used in didactical sciences. Methods: We used three well-known methods of analysis: The Delphi method, the Nominal Group Technique Questionnaire and pencil / paper Results: The data obtained showed that the prerequisites are overestimated although students have already learned in mechanics in programs during core and the first year of bachelor, they still have difficulties in the assimilation of basic knowledge on the subject. Conclusions: The results of the questionnaire and the Nominal Group Technisue (TGN) and the Delphi method are similar and complementary. It is clear that the use of TGN and the Delphi method and questionnaire are effective tools to diagnose the difficulties and obstacles of high school students in mechanics. So TGN and the Delphi method can be used not only to identify the problems of students with scientific concepts in mechanics, but also in other subjects.Keywords: the Nominal Group Technique TGN, the Delphi method, classical mechanics, physics, Questionnaire.