An optimum reactance one-port compensator for harmonic mitigation

The installation of electronic devices, digital equipment, and nonlinear loads in both industrial and domestic applications have dramatically increased in recent years, which in turn increased the level of harmonics in the system. Harmonic distortion is widely recognized as a significant cause of damage to, and mat-operation of electrical equipment. A harmonic filter can eliminate the potentially dangerous effects of harmonic currents created by nonlinear loads. There are two types of harmonic filters: passive filters and active filters. Passive filters are inexpensive compared with most mitigating devices. In this paper, reactance one-port compensator is designed for current harmonic mitigation. The optimal parameters the filter are determined using the Branch and Reduce Optimization Navigator (BARON) Nonlinear Programming Solver in the General Algebraic Modeling System (GAMS)

Impacts of Wind Power Variability on Generation Costs - An Overview

Although wind power is sustainable, environmental friendly and relatively inexpensive source of electricity, the effects of its intermittent nature on power systems need to be carefully investigated. This paper presents an up-to-date overview of the impacts of wind power variability on overall generation cost. Recent case studies from different utilities around the globe demonstrated that wind integration costs are much lower than anticipated by earlier studies

Study of some biochemical and genetic risk factors for atherosclerosis in systemic luus erythematosus patients

The aim of this study was to evaluate the relation between asymmetric dimethylarginine (ADMA ), high sensitive C-reactive protein (hs-CRP), monocyte chemoattractant protein-1 (MCP-1) ( both serum levels and the genotypes of the MCP-1 A-2518G polymorphism) with the development of carotid atherosclerosis in systemic lupus erythematosus patients (SLE). Thirty non menopause SLE female patients and twenty healthy age-matched females were included. Both cases and controls were subjected to evaluation of body mass index (BMI), intimal-medial thickness (IMT), fasting blood sugar (FBS), serum lipids. Serum ADMA, hs-CRP, and MCP-1, levels were measured by ELISA. MCP-1 polymorphism was detected by PCR-RFLP. Our results showed that values for IMT, hs-CRP, ADMA and MCP-1, were significantly higher in SLE patients than inhealthy control with more significant increase in SLE patients with IM

The Interaction among Insulin Resistance, Liver Fibrosis and Early Virological Response in Egyptian Patients with Chronic Hepatitis C

BACKGROUND: Hepatitis C virus (HCV) infection may induce insulin resistance (IR) irrespective of the severity of liver disease, and there is evidence of a central role for IR in failure to achieve sustained virological response (SVR) in HCV patients

Fibroscan versus liver biopsy in the evaluation of response among the Egyptian HCV infected patients to treatment

Background/aim: Hepatitis C virus (HCV) infection usually progress to chronic infection with subsequent cirrhosis and cancer. Therapies aim to eradicate the virus and prevent further progression. Interferon is claimed to have anti-fibrotic effect. Histopathology is the gold standard in diagnosis and grading of hepatic fibrosis, but transient elastogram (Fibroscan) can be used as alternative noninvasive modality. This prospective study aimed to evaluate the accuracy of fibroscan in diagnosis of liver fibrosis, and assess the effect of antiviral therapy on fibrosis stages in HCV patients. Patients and methods: The study was conducted from September 2012 to December 2014 as a project funded by Science and Technology Development Fund, Egypt, Grant No. 3448. It included 498 patients; 150 HCV cirrhotic patients as control, and 348 HCV naive patients grouped according to their liver biopsy into; mild (group I) and moderate (group II) fibrosis. They were examined using fibroscan (Echosens, Paris, France, device 502, M probe) before, 12, 24, and 48 weeks of therapy, with 300 patients (150 patients in each group) completed follow-up regardless of their response. The results of fibroscan were compared to each other and to liver biopsy. Results: Fibroscan can diagnose F1 at 6 kPa with 26% sensitivity, 8% specificity, AUC = 0.037; F2 at level of 7 kPa with 84.6% sensitivity, 71.3% specificity, AUC = 0.692 and F3 at 9.5 kPa with 96% sensitivity, 97% specificity, AUC = 0.997. The fibrosis results had regressed significantly after 48 weeks of starting therapy of both patients’ groups (p < 0.05). When categorized by response to therapy, responders showed significant decline in their fibroscan scores compared to non-responders of same fibrosis degree. Conclusion: Fibroscan correlated with histopathology in moderate (F2–F3), but not mild (F1) fibrosis. The degree of fibrosis regresses significantly in HCV responders on anti-viral INF based therapy. Besides its accuracy as noninvasive device in detecting degree of fibrosis, fibroscan can be very useful in assessment of degree of fibrosis during and after therapy

The Role of Hepatic Expression of STAT1, SOCS3 and PIAS1 in the Response of Chronic Hepatitis C Patients to Therapy

BACKGROUND: The underlying mechanisms of hepatitis C virus (HCV) resistance to treatment are unknown. Signal transducers and activators of transcription (STAT) proteins play a critical role in antiviral defense