Explore the vast range of titles available.

In this study, we tried to provide a theoretical framework for industrial clusters by defining them and highlighting their types, mechanisms and economic importance. The Italian experience was also mentioned as a pioneer in this field. We concluded on the one hand that industrial clusters have an impact on the macroeconomy, in particular on economic growth by creating added value and increasing employment opportunities, and on the other hand an impact on microeconomics such as obtaining a competitive advantage based on innovation, reducing industrial costs, improving quality.

This study aims to clarify the limited water resources in the Arab world, and the characteristics that make them require great security. Studies conducted by specialized Arab and regional organizations have unanimously agreed that the Arab region will face a large water deficit in the future medium term. Therefore, we recommend that the current available water resources should be counted in terms of their sources, the volume of supply and demand for them, to determine the water gap, the search for the impact of government spending on water resources and the feasibility of water investments in the face of the increasing demand.

Cette étude met en évidence l'impact de l'économie circulaire face aux défis de l'environnement et de la recherche d'efficacité économique, elle apparaît comme très prometteuse en intensifiant l'usage des matériaux, en réutilisant les matières premières plusieurs fois au lieu de les entasser dans des décharges, de les incinérer ou de les jeter à la mer. A cet effet, nous avons abordé plusieurs points tels que la fin de l'économie linéaire, la définition de l'économie circulaire, ainsi que les sept domaines de cette dernière, les enjeux et les opportunités qu'engendre l'économie circulaire. La dernière partie de cet article est une étude de cas de quelques entreprises françaises, qui se sont engagées dans cette nouvelle optique par l'application de différents objectifs. Pour profiter de toutes les opportunités qu'offrent l'application de l'économie circulaire par la gestion des déchets, par le recours aux matières premières secondaires, par l'éco-conception qui permet la baisse des émissions de gaz à effet de serre ou des rejets polluants, par la prestation de services plutôt que de produits. Le résultat de l'engagement de ces entreprises contribuera à une économie mondiale plus durable et plus florissante.

نهدف الى ابراز المصارف الإسلامية كظاهرة إقتصادية جديدة ميزت الثلث الأخير من القرن العشرين، حيث اعتبرت رد فعل حضاري واقتصادي للأمة الإسلامية، وإدراك المسلمين قصور النظام المصرفي الغربي في ملائمة المعتقدات الدينية، إضافة لوعيهم أهمية استغلال ثرواتهم من قبل مؤسسات مالية تنطلق من عقيدة الأمة وثقافتها بدل الركون إلى المصارف والمؤسسات المالية التي تتبنى النظام الغربي القائم على الفائدة المصرفية. بينت الدراسة أن المصارف الإسلامية نجحت في توفير قنوات تمويلية واستثمارية لم يعهدها العمل المصرفي من قبل، وعلى أسس ترتكز على مبدأ المشاركة في الأرباح والخسائر وتختلف عن الفائدة الربوية، لكن بالرغم من أهميته إلا أنه واجه الكثير من التحديات التي تركت أثارت على مسيرته وتطور عمله. كلمات مفتاحية: المصارف الإسلامية؛ الأزمات المالية؛ الأثر والعلاج.

Brown mussels (Perna perna) were exposed to cadmium (Cd), lead (Pb), and copper (Cu) concentrations under acute exposure and exposure-depuration tests for the estimation of biochemical biomarker catalase (CAT). The acute tests showed accumulated Cd, Pb, and Cu in Perna perna correlated linearly with the exposure concentrations ( R 2 = 0.794 , R 2 = 0.891 , and R 2 = 0.985 for Cd, Pb, and Cu, resp.). The results of CAT increased significantly in tissues of treatment mussels after 72 h exposure when compared to control. The values of total protein were disturbed in exposed groups when compared with control. These results suggest that metabolites and catalase activity were affected by heavy metal exposures. Analysis using the Spearman rank correlation coefficient showed that the CAT activity appeared to have a significant positive correlativity ( R s = 0.921 , R s = 0.949 , and R s = 0.949 for Cd, Pb, and Cu, resp.) with the accumulated Cd, Pb, and Cu concentrations, respectively. The result of exposure-depuration tests showed that there is a general tendency for CAT to decrease in depuration phase, suggesting that the induction of catalase is metal and/or mixture of metals dependent.