Contact Effect on the Dam Core Dimensions ( Case Study in Algeria: El-Izdihar Dam )

The stability of an earth dam with thin core is ensured by the upstream refills massifs. Earth dams with thin cores are lightened by the contact effect with refills massifs. A study of mechanic behavior taking into account the contact effect was performed for El-Izdihar earth dam without reservoir water effect which permits to predict its behavior and estimate the core thickness beyond which the contact has no effect. The finite element method was chosen as a method for the modeling

Comparative study of the effects of pre and post natal administration of a thyroid drug on testicular activity in adult rat.

Thyroid hormone is known to play a critical role in growth and development of rat testes with a specific effect on the differentiation of Sertoli cells leading to a normal evolution of germ cells. In the present study, we aimed to compare the effect of induced hypothyroidism during fetal and post-natal life on the structure and function of the testis in adult. Pregnant or lactating mothers were treated with 6-propyl-2-thiouracil (PTU) during 21 days and weight gain of pups was steady until adult age. Plasma hormonal levels were determined by RIA and morphology of testis was studied on sections stained with Masson's trichrome. Pre and early post natal hypothyroidism resulted in an impairment of body development and a diminution of thyroid hormone levels of treated rats. No significant effect on testicular development has been observed when hypothyroidism is induced in fetal life while it was associated with reduction in testis weight, diameter of seminiferous tubules and hormonal levels and delay in maturation of germ cells, when induced during early post natal life

Simultaneous optimal integration of photovoltaic distributed generation and battery energy storage system in active distribution network using chaotic grey wolf optimization

Goal. The integration of photovoltaic distributed generations in the active distribution network has raised quickly due to their importance in delivering clean energy, hence, participating in solving various problems as climate change and pollution. Adding the battery energy storage systems would be considered as one of the best choices in giving solutions to the mentioned issues due to its characteristics of quick charging and discharging, managing the quality of power, and fulfilling the peak of energy demand. The novelty of the proposed work is the development of new multi-objective functions based on the sum of the three technical parameters of total active power loss, total voltage deviation, and total operation time of the overcurrent protection relay. Purpose. This paper is dedicated for solving the allocation problem of hybrid photovoltaic distributed generation and battery energy storage systems integration in the standard IEEE 33-bus and IEEE 69-bus active distribution networks. Methodology. The optimal integration of the hybrid systems is formulated as minimizing the proposed multi-objective functions by applying a newly developed metaheuristic technique based on various chaotic grey wolf optimization algorithms. The applied optimization algorithms are becoming increasingly popular due to their simplicity, lack of gradient information needed, ability to bypass local optima, and versatility in power system applications. Results. The simulation results of both test systems confirm the robustness and efficiency of the chaotic logistic grey wolf optimization algorithm compared to the rest of the algorithms in terms of convergence to the global optimal solution and in terms of providing the best and minimum multi-objective functions-based power losses, voltage deviation and relay operation time values. Practical significance. Recommendations have been developed for the use of optimal allocation of hybrid systems for practical industrial distribution power systems with the renewable energy sources presence.Мета. Інтеграція фотоелектричної розподіленої генерації в активну розподільчу мережу швидко зросла завдяки її важливості для доставки чистої енергії, отже, участі у вирішенні різних проблем, таких як зміна клімату та забруднення. Додавання акумуляторних систем накопичення енергії може бути розглянуто як один з найкращих варіантів вирішення зазначених питань завдяки своїм характеристикам швидкої зарядки та розрядки, управління якістю енергії та задоволення піку енергетичних потреб. Новизна запропонованої роботи полягає у розробці нових багатоцільових функцій на основі суми трьох технічних параметрів сумарних втрат активної потужності, загальних відхилень напруги та загального часу спрацьовування реле захисту від перевантаження по струму. Мета. Стаття присвячена вирішенню проблеми розподілу гібридних фотоелектричних розподілених систем генерації та інтеграції систем накопичення енергії в стандартні активні розподільчі мережі з 33-шинами IEEE та 69-шинами IEEE. Методологія. Оптимальна інтеграція гібридних систем сформульована як мінімізація запропонованих багатоцільових функцій шляхом застосування нещодавно розробленої метаевристичної методики, заснованої на різних хаотичних алгоритмах оптимізації сірого вовка. Застосовані алгоритми оптимізації стають дедалі популярнішими завдяки своїй простоті, відсутності необхідної інформації щодо градієнту, можливості обходу локальних оптимумів та універсальності в застосуваннях щодо енергосистеми. Результати. Результати моделювання обох тестових систем підтверджують надійність та ефективність хаотичного логістичного алгоритму оптимізації сірого вовка в порівнянні з іншими алгоритмами з точки зору збіжності до глобального оптимального розв‘язання та з точки зору забезпечення найкращих і мінімальних багатоцільових функцій на основі втрат потужності, відхилення напруги та значень часу спрацювання реле. Практичне значення. Розроблено рекомендації щодо використання оптимального розподілу гібридних систем для реальних промислових розподільчих енергосистем із наявністю відновлюваних джерел енергії

Inhibitory Activity of Leaves Extracts of Citrullus colocynthis Schrad. on HT29 Human Colon Cancer Cells

Aims: Citrullus colocynthis is a plant endemic in Asia, Africa and in the Mediterranean basin. It is used in folk medicine against infections, inflammations and cardiovascular and immune-related diseases. There are further evidences of the use of Citrullus colocynthis Schrad in the treatment of cancer in traditional practices. The present study aimed to determine the potential antiproliferative effects of different Citrullus colocynthis leaf extracts on human cancer cells. Methodology: Antiproliferative and antioxidant effects on HT-29 human colon cancer cells were detected by MTS assay and a modified protocol of the alkaline Comet assay. In vitro antioxidant activities of different leaf extracts were evaluated through DPPH, \u3b2-carotene/linoleic acid and reducing power assays. Results: The leaf chloroform extract exhibited the higher cell growth inhibitory activity without induction of DNA damage; it showed to be able to significantly decrease DNA damage induced by H2O2 (100 M). This antioxidant activity seems to be comparable to that of vitamin C (1 mM). Ethyl acetate, acetone and methanol leaf extracts showed to be the most effective in reducing the stable free DPPH radical (IC50 =113 g/ml), in transforming the Fe3+ to Fe2+ (IC50 = 134 \ub5g/ml) and in inducing linoleic acid oxidation with an inhibition of 31.9 %. Conclusion: Our results confirm the antiproliferative potential of Citrullus colocynthis Schrad. on human cancer cells

An overview of burst, buckling, durability and corrosion analysis of lightweight FRP composite pipes and their applicability

© 2019 Elsevier Ltd. All rights reserved.The main aim of this review article was to address the performance of filament wound fibre reinforced polymer (FRP) composite pipes and their critical properties, such as burst, buckling, durability and corrosion. The importance of process parameters concerning merits and demerits of the manufacturing methods was discussed for the better-quality performance. Burst analysis revealed that the winding angle of ±55° was observed to be optimum with minimum failure mechanisms, such as matrix cracking, whitening, leakage and fracture. The reduction of buckling effect was reported in case of lower hoop stress value in the hoop to axial stress ratio against axial, compression and torsion. A significant improvement in energy absorption was observed in the hybrid composite pipes with the effect of thermal treatment. However, the varying winding angle in FRP pipe fabrication was reported as an influencing factor affecting all the aforementioned properties. Almost 90% of the reviewed studies was done using E-glass/epoxy materials for the composite pipe production. By overcoming associated limitations, such as replacing synthetic materials, designing new material combinations and cost-benefit analysis, the production cost of the lightweight FRP composite pipes can be decreased for the real-time applications.Peer reviewe