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Voltage instability is considered as one of the main threats to secure operation of power system networks around the world. Nowadays, Integration of large-scale wind power may have severe impacts on the power system operation. Stable, reliable and economic operation of the power system under the massive integration of wind power is a big challenge to power system operators. This paper scrutinizes to study the voltage stability problems for the integration of wind power to the IEEE-39 bus-systems. The main objective of this study is to analyze the voltage stability of the IEEE-39 bus networks with large-scale wind power under normal operation using PV and QV analyses. As one of the classic static Voltage stability assessment (VSA) method, the P-V curve is widely used in identifying the weak buses in one power system. Normally, there is a required range of bus voltage variation that restricts load with fixed power factor within a maximum value. The loading margin can be defined as the distance between the operating point and the maximum load. These steady-state methods, which inherently require less computational capability, can indicate the level of stability of a power system. Therefore, QV curves analysis tools are used in this paper. The importance of accurate representation of the reactive power capabilities of wind generators in voltage stability studies was emphasized in the analyses. These analyses define the amount of reactive power required to enhance voltage stability and hence can be improved by adding suitable reactive power compensator. Here STATCOM is used as a reactive power compensator. Simulation of the 39 bus-IEEE network with integrated wind generators are developed using PSS/E software. يعد أتزان الجهد واحدة من أهم المتحديات لأنظمة الطاقة حول العالم.يعتبر التوسع في ربط محطات الرياح له تأثير بالغ علي أنظمة الطاقة. فطتحديات أنظمة الطاقة تتمثل في الثبات والاعتمادية والتشغيل الاقتصادي للشبکة الکهربائية. وهذا البحث العلمي قائم علي دراسة استقرار الجهد لأنظمة الطاقة مع وجود العديد من مشاريع الرياح المرتبطة بالشبکة الکهربائية. وقد تم اختيار شبکة مکونة من ٣٩ بارة لتمثل حالة الدراسة. ومن أهم أهداف هذه الدراسة هو دراسة وتحليل وضع الجهد الکهربائي للشبکة المشار إليها مع وجود العديد من محطات طاقة الرياح بنسب انتشار مختلفة وذلک في وضع التشغيل العادي باستخدام برنامج تحليلى الجهد والقدرة الفعالة وتحليل الجهد والقدرة الغير فعالة وذلک باستخدام برنامج محاکاة نظام الطاقة للهندسة. ويعد تحليل الجهد والقدرة الفعالة أحد العوامل لتقييم وضع الجهد الکهربائي للشبکة بين وضع التشغيل العادي وأقصي تحميل ممکن للشبکة حيث أن للجهد الکهربي سماحية يتغير في حدودها مع الحفاظ علي استقرار الشبکة. أما تحليل الجهد والقدرة غير الفعالة فهو مقياس لقدرة البارات الغير فعالة وتأثيرها المباشر علي الجهد الکهربائي وبيان نقاط الضعف في الشبکة حيث عدم توافر ما يکفي من القدرة غير الفعالة وما يترتب عليه من إمکانية إضافة محسنات جهد لتلک النقاط کما هو موضح في هذه الدراسة.

Background: T2DM is a major risk factor for heart failure, peripheral arterial insufficiency and microvascular complications, affecting life quality and expectancy. Diabetes also increases coronary death rates conferring the patient a worst prognosis after having the first CHD event. The mortality rate in non-diabetic patients was less compared to diabetic patients who experienced CHD. Objectives: to study was the association of nontraditional risk factors with incidence of coronary heart disease in Patient with Type 2 Diabetes. Patients & Methods: Our study had been carried out in cardiology department, Zagazig University from April 2017 to December 2017. The study included 105 patients divided into 3 groups; they were young and middle aged subjects selected conveniently according to specified groups (normal control group, diabetic control group without history of coronary artery disease and ischemic heart disease group with history of coronary artery disease. History and physical examinations were recorded and laboratory tests were performed for all patients. Results: showed that there ws a statistical significant difference regarding Diastolic dysfunction, Ventricular hypertrophy, Uric acid, Serum hsCRP, Serum fibrinogen and Homocystein in T2DM patients group. Conclusions: Cardiovascular risk factors were higher in subjects with diabetes compared to subjects without diabetes, Non-traditional cardiovascular risk factors may be related independently to incident coronary heart disease in T2DM patients.

Background The researchers are trying to evaluate the measurement of: Intact parathyroid hormone (iPTH) and serum total calcium (sCa) levels for predicting hypocalcemia after total thyroidectomy (TT). Methods The sample of this single center prospective study consists of (100) patients, where (77) females and (23) males with an age range between (28) and (65) (the mean level is, 48.17 ± 6.54). These selected patients underwent total thyroidectomy (TT) in the general surgery department, Benha university hospital from the period of June 2019 to February 2020. Levels of sCa and iPTH were measured aat several times preoperatively, 10 min, 48 h, 3, 6, 9 months, and 1 year after being after gone TT. Results Among the entire study sample, 23 patients (23%) developed transient hypoparathyroidism and hypocalcemia (˂8.5 mg/dl), none of them developed permanent hypoparathyroidism and hypocalcemia. The cut-off point of PTH has been 10 min after TT was at 23 pg/mL as it was the best compromise between sensitivity and specificity for predicting hypocalcaemia. It has been found that Patients who have a PTH greater than 23 pg/mL can be discharged safely after 24 h. Patients who have PTH of less than 23 pg/mL were observed for an additional 24 h, and the study found that timely treatment initiation is recommended. A PTH ˂ 10 pg/mL measured at 48 h after surgery had a sensitivity, specificity as well as an accuracy of 100%, for predicting hypocalcemia after TT. The accuracy of a single PTH concentration at 48 h was useful for predicting hypocalcemia [Area under receiver–operator characteristic curve (AUC) 1; confidence interval (CI), 95%, 0.85–0.94]. Conclusion Patients with iPTH ˂ 10 pg/mL, and sCa levels ˂ 7.4 mg/dL are at higher risk of developing hypoparathyroidism and hypocalcemia after TT., Highlights • Incidence of Post-thyroidectomy transient hypoparathyroidism ranges between 0.3 and 49%, while permanent hypoparathyroidism is 13%. • Incidence of hypocalcemia following total thyroidectomy ranging between 3% and 40% and is usually transient, while permanent hypocalcemia is ≤ 2%. • Post-thyroidectomy PTH accurately predict hypocalcemia.

Wheat may be infected by the aflatoxigenic mold Aspergillus flavus during pre- and post-harvest activities. Control strategies reported to manage aflatoxin contamination of wheat are expensive and require extensive testing to verify the absence of toxic secondary metabolites or newly formed compounds. The objective of this study was to develop an in vitro new control strategy based on assessing the influence of wheat husks on aflatoxin production by A. flavus in liquid culture. The results showed that aflatoxin production is significantly influenced by the existence of husks in the wheat forms used as carbon substrates according to the following order: full wheat grains < half-crushed wheat grains < wheat flour 82% < wheat flour 72%. By applying a fractional factorial design and a response surface methodology, maximum aflatoxin production (2.567 ng/mg) was predicted when wheat flour 72% (39 g/l) as a carbon source, yeast extract (5 g/l), and a 75-ml medium volume/250 ml flask were utilized. At this optimized condition, after addition of wheat husk extract, the growth and synthesis of aflatoxins of A. flavus were repressed by 74.85 and 98.72%, respectively. This finding paves the way to examine the antifungal potential of wheat husk constituents and to compare their efficacy with thyme, cinnamon, sweet basil, and coriander essential oils, which possess antimycotic activities. Accordingly, the wheat husk component SiO2 showed the highest growth inhibition (67.04%) and reduction of A. flavus aflatoxins (82.67%). These results are comparable to those obtained from various examined antimycotic essential oils.

This paper presents a new composition of the reinforced concrete material; then, as verification, a study of such proposed composition in the flexural behavior of reinforced concrete beams is done. The work is divided into three stages. Firstly, the use of Damaged Securit Glass (DSG) as a replacement of coarse aggregate within concrete mixes is investigated, which leads to solving an environmental problem. Secondly, an experimental program to examine the flexural behavior of Glass Reinforced Concrete Beam (GRCB) is conducted, in which the casted beams are composed of the new proposed DSG concrete mixes and reinforced by locally-manufactured GFRP bars. The study focuses on simply supported GRCB subjected to four-point bending load. Finally, a numerical verification is carried out by implementing non-linear Finite Element Analysis (FEA) using ANSYS 14.0. The reliability of the FE models is demonstrated by a comparison with the experimental results, which shows good agreement in both load-deflection relationships; as well as failure patterns. Different study results are highlighted; such as: Ultimate load, reinforcement ratio – hence ductility – of GFRP bars, and trend of both compressive strain of concrete and tensile strain of reinforcement bars.The results confirm that the new mixes of Glass Reinforced Concrete (GRC) which have the DSG in its component possess the same ultimate load of similar conventional reinforcement concrete beam (RCB). The most equivalency has occurred when a 20% of weight of the coarse aggregate is replaced by DSG. The results of a flexural study of GFRP beams show that compared with similar RCB, the maximum deflection is decreased by about 47%, the maximum compressive strain of concrete is decreased by about 75%, and the maximum tensile strain of steel is decreased as well by about 92%. Furthermore, when GFRP bars are used in the new GRC mixes, a remarkable increase of the ultimate load is achieved by about 14%. Subsequently, a related increase of the maximum deflection, ultimate tensile strain in the GFRP bars, and ultimate compression strain of concrete are also achieved. Keywords: Damaged Securit Glass (DSG), Glass Fiber-Reinforced Polymer bars (GFRP), Glass Reinforcement Concrete (GRC), RC beam flexural behavior, Cracks, Finite Elements Analysis (FEA)

In the design of most bridge girders with composite girders composed of steel–concrete composite plate girders, an opening in the steel girder is often used to provide passage for utility ducts and pipes. This results in significant savings in material and construction costs. So it is necessary to study the effect of an opening in the web steel on the behavior of the composite girders if the designer wishes to provide adequate opening in the structural elements without reducing its load carrying capacity. In this paper, a non-linear finite element analysis has been done to analyze the deflection in the steel section and internal stresses in the concrete slab for continuous composite girders with a single rectangular opening in the steel web. ANSYS computer program (version 15) has been used to analyze the three-dimensional model. The reliability of the model was demonstrated by comparison with experimental results of continuous composite beams without an opening in the steel web carried out by another author. The parametric analysis was executed to investigate the width, height, and position of the opening in one span on the behavior of a composite girder under vertical load. The results indicated that when the width of opening is less than 0.05 of length of a single span and the height is less than 0.15 of the steel web, the deflection and internal stresses increased less than 10% comparing to continuous composite girders without an opening.

Eight Streptomyces isolates were collected from three deteriorated icons dated back to 18–19th centuries. Streptomyces isolates cause different deterioration symptoms such as disfiguration, blackening of red lead and thinning of linen fibers in the canvas. Dielectric barrier discharge (DBD) plasma were used in decontamination Streptomyces colonizing icons and a period 8 min was sufficient for decontamination of most isolated Streptomyces and the distance 3 mm was more effective than other distances. DBD plasma treatment for different periods (4, 8, 10 min) for different distances (3, 5, 10 mm) did not cause any visual chromatic alteration for irradiated pigments of red lead, cinnabar HgS, PbCO 3 , black carbon, copper acetate (CuCOOH, H 2 O), hematite, limonite and Egyptian blue. On the other hand, FTIR spectra indicated no modification in the structure of tested binder in the grounds. Finally, DBD plasma did not affect on the tensile strength of linen canvas.

Objective: Evaluate the diagnostic accuracy of 256 slices computed tomography (CT) coronary angiography (CA) (multidetector CT [MDCT]) in the assessment of native coronary arteries and grafts in post-coronary artery bypass graft (CABG) surgery Egyptian patients. Patients and Methods: It included 70 patients with a history of isolated CABG with recurrent chest pain. We excluded patients with a history of redo CABG or other open-heart surgeries, renal impairment, severe claustrophobia, chronic liver disease, dye allergy, tachycardia with contraindication to beta blockers (BB), pregnancy. All patients were subjected MDCT and CA. Both examinations were done within 3 months. Results: In our study, 161 grafts evaluated (63 left internal mammary artery [LIMA] in situ grafts, 5 right internal mammary artery (RIMA) and 2 radial grafts, and 91 venous grafts). CA failed to detect 3 LIMA and 7 venous grafts. All were seen only by MDCT. For grafts CT compared to CA has sensitivity (91.5%, 84.8%), specificity (98%, 100%), accuracy (95.65%, 96.9%), positive predictive value (PPV) (96.43%, 100%), and negative predictive value (NPV) (95.24%, 96.2%) in the assessment of significant stenosis and total occlusion of grafts, respectively. For grafted vessels CT has sensitivity (94%, 100%), specificity (98%, 100%), accuracy (96.94%, 100%), PPV (95.92%, 100%), and NPV (97%, 100%) in the assessment of significant stenosis and total occlusion of grafted vessel, respectively. For native vessels CT has sensitivity (100%, 97.7%), specificity (84.2%, 98.4%), accuracy (97.14%, 98.1%), PPV (96.6%, 97.7%), and NPV (100%, 98.37%) in the assessment of significant stenosis and total occlusion of native vessels, respectively. Conclusion: Our study demonstrated a high diagnostic accuracy of MDCT for the assessment of bypass grafts and grafted or native coronary arteries compared with CA. Detection of grafts or native vessels occlusion was better than detection of substantial stenosis. MDCT is a good negative test for native vessels as it has a high sensitivity since it tends to overestimate stenosis degree, so patients with negative MDCT angiographic results mostly have patent vessels.

Background: No-reflow phenomenon is the most striking example of myocardial reperfusion clinical failure. It caused by a lack of adequate blood flow in tissues after successful recanalization of infarct-related artery and was of multifactorial nature. Patients with «no-reflow» have highly