Experimental And Numerical Studies On Thermal Analysis Of Heat Pipes For Computer Cooling Applications

In computer industry, the growing development and demand for processing power necessitate efficient design of processors to conduct operations faster; consequently, the need for cooling techniques to dissipate the associated heat is quite obvious. Hence, it is highly desirable to explore high-performance cooling devices, especially for CPU cooling. In the present study, multi and twin U-shape vertical heat pipes, and single L-shape horizontal heat pipe, were investigated experimentally and numerically. Thermal analysis was performed under both natural and forced convection modes

Thermal Insulation in Buildings Using Two Wall Cavities

The present work examines a system that uses two separated wall cavities filled with air which can be used as a thermal insulator in buildings. It is well known that stationary air has lower thermal conductivity 0.026 W/m.K. This has made it of practical interest in many applications such as in thermal insulation materials (e.g. porous materials) and as thermal insulator (e.g. enclosures, wall cavities). Specifically this work investigates the use of two separated wall cavities that trap air inside each one and placed in a building wall where the heat transfer is expected. And to achieve that, the rate of heat transfer through this wall is first calculated with the assumption of pure conduction (i.e. trapped air in the two wall cavities is assumed to be stationary). Then convection heat transfer rates through the two wall cavities are estimated based on the Nusselt numbers and hence the dominating heat transfer mechanism (conduction and/or convection) is explored. Taking into account all the above, introducing two cavities filled with air to building wall can work effectively as thermal insulator as indicated by lower Nusselt numbers and hence lower convection heat transfer rates through the two wall cavities. Advantage of using two wall cavities over one wall cavity of larger thickness is evidenced by the higher convection heat transfer rates which are associated with one wall cavity of larger thicknesses – that's the wall with two cavities can effectively resist the heat flow than the wall with one cavity of larger thicknes

Novel therapeutic strategies for spinal osteosarcomas

At the dawn of the third millennium, cancer has become the bane of twenty-first century man, and remains a predominant public health burden, affecting welfare and life expectancy globally. Spinal osteogenic sarcoma, a primary spinal malignant tumor, is a rare and challenging neoplastic disease to treat. After the conventional therapeutic modalities of chemotherapy, radiation and surgery have been exhausted, there is currently no available alternative therapy in managing cases of spinal osteosarcoma. The defining signatures of tumor survival are characterised by cancer cell ability to stonewall immunogenic attrition and apoptosis by various means. Some of these biomarkers, namely immune-checkpoints, have recently been exploited as druggable targets in osteosarcoma and many other different cancers. These promising strides made by the use of reinvigorated immunotherapeutic approaches may lead to significant reduction in spinal osteosarcoma disease burden and corresponding reciprocity in increase of survival rates. In this review, we provide the background to spinal osteosarcoma, and proceed to elaborate on contribution of the complex ecology within tumor microenvironment giving arise to cancerous immune escape, which is currently receiving considerable attention. We follow this section on the tumor microenvironment by a brief history of cancer immunity. Also, we draw on the current knowledge of treatment gained from incidences of osteosarcoma at other locations of the skeleton (long bones of the extremities in close proximity to the metaphyseal growth plates) to make a case for application of immunity-based tools, such as immune-checkpoint inhibitors and vaccines, and draw attention to adverse upshots of immune-checkpoint blockers as well. Finally, we describe the novel biotechnique of CRISPR/Cas9 that will assist in treatment approaches for personalized medication.This work is funded by a grant (MPP 320133) from the American University of Beirut to Dr. Ali H. Eid

The Optimization of Thickness and Permeability of Wick Structure with Different Working Fluids of L-Shape Heat Pipe for Electronic Cooling

Abstract As part of the ongoing research on finned L-shape heat pipes for electronic cooling, the present work focuses on the optimization of the thickness and permeability of wick structure of L-shape heat pipe, using different working fluids. DOptimal Designs Software is used to obtain the optimal solution to align the competing parameters such as the working fluid properties, thickness of the wick and the type of wick structure. The optimization results yielded that a wick thickness of 0.52 mm and permeability of 1.39E-11 m 2 with water as a working fluid could produce the minimum temperature difference between the evaporator and condenser sections of 9.56 °C and liquid pressure drop of 5730 Pa, which could increase the heat transport capability from 35 W to 43 W. These results reveal that the performance of L-shape heat pipe in terms of heat transport capability is improved by 20%

Stepping into Renewable Energy: Advantages & Disadvantages – Development & Future

The distribution of renewable energy becomes increasingly important in the future, particularly in the areas where the electricity generation is more difficult or impossible. Also, the question of renewable energies is rising for environmental reasons, because the renewable energy use no emissions of pollutants such as carbon dioxide, nitrogen oxide and sulfur dioxide as in the case of conventional electricity generation in power plants. This article examines the different renewable energy types and their definitions. Stepping into renewable energy is explained and illustrated. Here, the advantages and disadvantages of types of energy are considered and compared in order to determine the use of profitability. In addition, the distribution of individual types of energy taken in general considered

Heavy Metal Removal from the Water of the River Nile Using Riverbank Filtration

Riverbank filtration (RBF) is considered as a natural treatment process. During this process, a group of chemical, physical, and biological processes occur when water moves through the soil along the bank of the River Nile, which can act as a conventional treatment process. RBF is one of the most effective solutions that the Egyptian government and responsible parties should embrace. Egypt has started to use the RBF technique widely in many sites through the path of the River Nile. This study provides a detailed analysis of the RBF technique; it represents the outlet quality of the water in a study performed on the River Nile. The effect of RBF on water quality can be measured using the software designed for this study. The study’s main aim is to improve the water quality of the River Nile by removing heavy metals from the water by using an effective and fast method of treatment, which is riverbank filtration. The results of the research’s experimental study show the average percentage of metal removal for iron, cobalt, lead, zinc, and copper are 74.04%, 74.44%, 70.72%, 75.1%, and 70.8%, respectively. These results have proved that RBF acts as a substantial barrier versus heavy metals

Paretic-Limb-Only Plyometric Training Outperforms Volume-Matched Double-Limb Training for Ameliorating Balance Capability and Gait Symmetry in Adolescents with Unilateral Cerebral Palsy: A Comparative Study

Adolescents with unilateral cerebral palsy (U-CP) experience an asymmetrical posture because the less-affected lower limb is preferred for bodyweight support as a strategy of compensating for the paretic side’s muscular weakness. This study was designed to compare the effect of 12 weeks of paretic-limb-only plyometric training (PLPT) and volume-matched double-limb training (DLPT) on balance capability and gait symmetry in adolescents with U-CP. Sixty-nine adolescents with U-CP were randomly assigned to PLPT, DLPT, or a control group (n = 23 each). Treatment was delivered twice/week (with at least 48 h recovery intervals) for 12 weeks in succession. The directional (LoSdirectional) and overall (LoSoverall) limits of stability in addition to the temporal (T-GSI) and spatial (S-GSI) gait symmetry indicis were assessed pre- and post-treatment. The LoSdirectional improved significantly in the PLPT group compared to either the DLPT or control group (for the forward (p = 0.027 and <0.001, respectively), backward (p = 0.037 and <0.001, respectively), affected-side (p = 0.038 and 0.004, respectively), and less-affected-side (p = 0.018 and 0.016, respectively)), and this was also the case for the LoSoverall (p < 0.001). Additionally, The T-GSI and S-GSI scores decreased significantly in the PLPT group compared to the DLPT (p = 0.003 and 0.047, respectively) or control (p = 0.003 and 0.036, respectively) group, indicating the development more symmetrical gait patterns. In conclusion, PLPT is likely more effective for enhancing balance capabilities and promoting symmetrical gait patterns than DLPT. Thereupon, it is worthwhile for physical rehabilitation practitioners to include the PLPT paradigm into the intervention plans for adolescents with U-CP

New Meroterpenoid Derivatives from the Pomegranate-Derived Endophytic Fungus <i>Talaromyces purpureogenus</i>

In this study, we report the isolation of two new meroterpenoids, miniolutelide D (1) and miniolutelide E (13-epi-miniolutelide C) (2), along with two meroterpenoidal analogues (3 and 4) and two phenolic compounds (5 and 6) from the endophytic fungus Talaromyces purpureogenus derived from Punica granatum fruits. Their structures were elucidated using extensive MS, 1D, and 2D NMR spectroscopic analyses as well as by comparing with data in the literature. The absolute configurations of 1 and 2 were determined using TDDFT-ECD calculations. Antimicrobial activity was evaluated. Compound 5 displayed significant activity against methicillin-resistant Staphylococcus aureus strain ATCC 700699 and moderate activity against S. aureus strain ATCC 29213