5,100 research outputs found

    The application of BIM tools to explore the dynamic characteristics of smart materials in a contemporary Shanashil building design element

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    Traditional architecture is known for its crafted facade features that respond to environmental, social and cultural requirements. Contemporary architecture produced façade features that attempted to enhance local design identity and local culture. Despite the advantages of modern technology, architectural elements have difficulties in fulfilling the idea of sustainable elegance that once traditional elements provided. This problem calls for an interdisciplinary design approach to deliver sustainable design solutions that positively adapt to the surrounding environment as well as maintain the state of elegance in design. With this in mind, the research aims to explore the role of new glass technologies to improve the performance and at the same time maintain the design value of traditional façade element “shanashil” in Baghdadi buildings. This research utilises BIM tools and uses smart materials to restore the lost value in design, which mimics the dynamic characteristics observed in nature, inspired by biomimetics strategies. Such qualities are found in the characteristics of smart dynamic glazing material particularly in the switchable, reversible properties of transparency and coloration efficiency. The material characteristics are attached to a 3D digital prototype to visualise the difference between dynamic and static properties through the use of technology tools Revit plugin and smart glazing virtual reality prototype. This research concludes that the dynamic characteristics of smart glazing materials are effective in delivering a multifunctional design quality to collectively blend in harmony with the surrounding environment

    Simvastatin Ameliorates Diabetic Cardiomyopathy by Attenuating Oxidative Stress and Inflammation in Rats

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    Simvastatin is a lipid-lowering agent used to treat hypercholesterolemia and to reduce the risk of heart disease. This study scrutinized the beneficial effects of simvastatin on experimental diabetic cardiomyopathy (DCM), pointing to the role of hyperglycemia-induced oxidative stress and inflammation. Diabetes was induced by intraperitoneal injection of streptozotocin and both control and diabetic rats received simvastatin for 90 days. Diabetic rats showed significant cardiac hypertrophy, body weight loss, hyperglycemia, and hyperlipidemia. Serum creatine kinase MB (CK-MB) and troponin I showed a significant increase in diabetic rats. Simvastatin significantly improved body weight, attenuated hyperglycemia and hyperlipidemia, and ameliorated CK-MB and troponin I. Simvastatin prevented histological alterations and deposition of collagen in the heart of diabetic animals. Lipid peroxidation and nitric oxide were increased in the heart of diabetic rats whereas antioxidant defenses were decreased. These alterations were significantly reversed by simvastatin. In addition, simvastatin decreased serum inflammatory mediators and expression of NF-κB in the diabetic heart. Cardiac caspase-3 was increased in the diabetic heart and decreased following treatment with simvastatin. In conclusion, our results suggest that simvastatin alleviates DCM by attenuating hyperglycemia /hyperlipidemia-induced oxidative stress, inflammation, and apoptosis

    Effect of drying of different light hardwood tropical timber species on durability against Coptotermes curvignathus Holmgren under laboratory and field tests

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    The effects of drying temperature and duration on the durability of Lagerstroemia sp. and Cinnamomum sp. against subterranean termites, Coptotermes curvignathus, were evaluated in no-choice and choice laboratory tests as well as in the aboveground test. Samples measuring 25 mm × 25 mm × 6 mm and 100 mm × 40 mm × 20 mm were dried in an oven at three different temperatures: 60°C, 80°C, and 100°C for two different time periods: 10 and 15 d. In comparison between the control sample and the treated sample, the control sample showed the highest MC, the lowest visual rating, the lowest termite mortality, and the highest weight loss. For the treated samples, the results show that the samples for both wood species have a low resistance limit to termites at low temperatures and a short-drying time. The weight loss is also high for samples with high MC. The mortality rate of termites was also high in samples dried at high temperatures over a long period of time compared with samples dried at low temperatures for a short period of time. The visual rating results also showed the same trend as the weight loss results. The results for these three categories are identical for the no-choice, choice, and aboveground tests. The analysis demonstrates that the high material resistance of tropical wood species is mostly dependent on the temperature and length of time spent in the kiln

    A proposed model for frequency tuned antennas used in mobile communication systems

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    The antenna is considered as one of the most fundamental elements in wireless communication systems, especially in mobile devices. Desirable specifications of antennas include covering wide range of operating frequencies, while maintaining high quality of system performance over the whole range of operating frequencies. Therefore, the ability of tuning the resonant frequency of the antenna without altering its physical dimensions would be highly recommended in up-and-coming designs of antennas in mobile devices. This research work proposes a model for tuning the operating frequency of the inverted F-antenna over a reasonably wide range of frequencies, via altering the electromagnetic properties of its ferrite material. In this proposed model, it will be shown that the electronic control of the permeability of the ferrite material of the antenna leads effectively to a significant shift in its resonant frequency, and hence to an overall improvement in the performance of the communication system

    Prevalence of the Antibiotic Resistance Genes in Coagulase-Positive-and Negative-Staphylococcus in Chicken Meat Retailed to Consumers

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    The use of antibiotics in farm management (growing crops and raising animals) has become a major area of concern. Its implications is the consequent emergence of antibiotic resistant bacteria (ARB) and accordingly their access into the human food chain with passage of antibiotic resistance genes (ARG) to the normal human intestinal microbiota and hence to other pathogenic bacteria causative human disease. Therefore, we pursued in this study to unravel the frequency and the quinolone resistance determining region, mecA and cfr genes of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), methicillin-resistant coagulase-negative staphylococci (MRCNS) and methicillin-susceptible coagulase-negative staphylococci (MSCNS) isolated from the retail trade of ready-to-eat raw chicken meat samples collected during one year and sold across the Great Cairo area. The 50 Staphylococcus isolated from retail raw chicken meat were analyzed for their antibiotic resistance phenotypic profile on 12 antibiotics (penicillin, oxacillin, methicillin, ampicillin-sulbactam, erythromycin, tetracycline, clindamycin, gentamicin, ciprofloxacin, chloramphenicol, sulfamethoxazole-trimethoprim and vancomycin) and their endorsement of the quinolone resistance determining region, mecA and cfr genes. The isolation results revealed 50 isolates, CPS (14) and CNS (36), representing ten species (S. aureus, S. hyicus, S. epidermedius, S. lugdunensis, S. haemolyticus, S. hominus, S. schleiferi, S. cohnii, S. intermedius and S. lentus). Twenty seven isolates were methicillin-resistant. Out of the characterized 50 staphylococcal isolates, three were MRSA but only 2/3 carried the mecA gene. The ARG that bestows resistance to quinolones, β-lactams, macrolides, lincosamides and streptogramin B (MLS(B)) in MRSA and MR-CNS were perceived. According to the available literature, the present investigation was a unique endeavor into the identification of the quinolone-resistance-determining-regions, the identification of MRSA and MR-CNS from retail chicken meat in Egypt. In addition, these isolates might indicate the promulgation of methicillin, oxacillin and vancomycin resistance in the community and imply food safety hazards
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