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Introduction: The arterial circle of the base of the skull is an anastomotic arterial system between the carotid and vertebrobasilar territory. It has an interest in ischemic or hemorrhagic vascular disease and tumor pathology of the skull base. Observation: We describe the case of a patient with a rare anatomical variant of the anterior complex of the arterial circle of the skull base which has produced severe neurological disorders. Discussion: The anterior complex of the arterial circle of the skull base is formed by the two anterior cerebral arteries and the anterior communicating artery. The main vascular changes occur very early in fetal life. There takes place complex phenomena of appearance, regression and anastomosis. These anatomical variants would favor the developpement of vascular malformations due to modified hemodynamics. It is necessary to accurately map the anterior cerebral vascularization in particular in case of aneurysms. Conclusion: A perfect knowledge of these variants is essential for a good neurosurgical and endovascular treatment of patients.

While some studies indicate that flipped classrooms offer many positive educational outcomes, other studies draw attention to limitations associated with flipped classroom (students' limited preparation prior to class, students' need for guidance at home, students' inability to get immediate feedback while they study at home, and little research has focused on students' learning outcomes, such as: satisfaction and motivation). This paper attempts to address several of these limitations through exploratory studies conducted in an Algerian University. The approach proposed in this paper called Flipped classroom based on Context-Aware mobile learning system (FC-CAMLS) aims to provide learners with an adapted course content format based on their feedback and context. The latter has a significant influence on multimedia content in adaptive mobile learning. The system was implemented in an English Language course. It was expected that the FC-CAMLS increased the management of students' heterogeneity. A quantitative analysis by means of structural equation modeling was performed to analyze the caUnited States of Americal relationships between knowledge, skills, motivation and students' satisfaction. The results show that the system has positive effects on students' knowledge, skills, and motivation. Finally, our research provides useful results that the use of the context dimensions and learner's feedback in adaptive mobile learning is more beneficial for learners especially in the flipped classroom.

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It is well known that the over exploitation of soil resources decreases the density and diversity of arbuscular mycorrhizal (AM) fungal propagules. It has been postulated that agricultural practices could promote the occurrence and functioning of remaining and resilient AM fungal ecotypes in order to benefit from AM associations. Using C. ochroleuca, a highly mycotrophic plant species, the aims of this study were to determine in controlled conditions, the impact of this legume species on: (i) the mycorrhizal soil infectivity (MSI), (ii) the Rock Phosphate (RP) solubilising activity and (iii) the soil microbial functions. The expected benefits of C. ochroleuca cultivation have been evaluated by comparing its biological influences with those recorded with a non-mycorrhizal plant species, Brassica oleracea in order to attest of the importance of the AM potential in RP weathering and soil functioning. The results show that: C. ochroleuca was effective in improving the mycorrhizal soil potential, (ii) functional abilities of soil microflora were influenced by the cultured plant species and the mycorrhizal soil potential and (iii) the efficiency of rock phosphate amendment on plant growth depended on the level of mycorrhizal soil potential and was linkedto the extent of the mycorrhizal network.The C. ochroleuca impact was significantly reinforced with KRP amendment (i.e. +29.3% for the Catabolic Eveness, +45.7% for the hyphal length). According to these results, it could be concluded that agricultural strategies based on the management of local biodiversity (i.e. the use of native legume species) could be considered as a sustainable practice to optimally manage AM fungi and to ensure their functionalities in order to maintain a sustainable production of food crops in the tropics.

The biotransformation during storage of petroleum refinery sludge was evaluated by physicochemical and spectroscopy analyses. The abatement rate of organic matter has reached 50.5% after 14 months of storage. The humic substances have decreased of about 49% at the end of storage indicating that the OM was mineralized into inorganic compounds (CO2, N2…). The XRD of dried samples shows the presence of a large proportion of silica (SiO2), carbonate (CaCO3), Hercynite (Al2FeO4) and hemihydrate calcium sulphate (2CaSO4.H2O). Hematite (Fe2O3) and anhydrite (CaSO4) were found as a new appeared phase. Pb, Cd, Cr, Cu, Ni and Zn were the most identified heavy metals in the petroleum samples. Their increase at the end of storage was explain by the organic matter degradation. FTIR analysis show that the carbonate, sulphate and silica are the most identified compounds beside the organic matter., Moroccan Journal of Chemistry, Vol 4, No 4 (2016)