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991.
Polymer nanocomposites used in underground cables have been of great interest to researchers over the past 10 years. Their preparation and the dispersion of the nanoparticles through the polymer host matrix are the key factors leading to their enhanced dielectric properties. Their important dielectric properties are breakdown strength, permittivity, conductivity, dielectric loss, space charge accumulation, tracking, and erosion, and partial discharge. An overview of recent advances in polymer nanocomposites based on LDPE, HDPE, XLPE, and PVC is presented, focusing on their preparation and electrical properties.  相似文献   
992.
Literature of Steel Beams with a thin-walled trapezoidal Corrugated Web (SBCWs) shows that the capacity of SBCWs is affected by both the fatigue cracks initiated along the inclined folds (IFs) and the maximal additional stress located in the middle of the IFs. An experimental investigation on the behaviour of hybrid SBCWs under flexure is presented in this paper. This study focuses on the effect of the welding IF between the web and flanges (IFs welded or non-welded), the horizontal-fold length (200, 260, and 350 mm), and transversal flange stiffeners on the failure mechanism of the SBCW under three line load. Accordingly, six hybrid specimens were fabricated, instrumented, and tested (five SBCW specimens and one specimen with a flat web). The test setup was designed to generate shear and a moment in the testing zone via three-point bending. The results indicated that non-welded IFs specimens with or without flange stiffeners failed owing to web tearing after web and flange local buckling. The failure mode of the specimen with continuous welding between the web and flanges was local flange buckling. Finally, the paper presents a comparison between the experimental results and the European Code to predict the capacity of the flange towards local buckling. It was concluded that the non-welding the IFs affected the inelastic behaviour and the capacity of the SBCWs. In addition, the bending resistance equations presented by EN 1993-1-5 can safely predict the test results of the non-welded inclined fold and yield a high safe variation.  相似文献   
993.
Abdominal Radiology - Prior iterative reconstruction (PIR) uses spatial information from one phase of enhancement to reduce image noise in other phases. We sought to determine if PIR could reduce...  相似文献   
994.
995.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Ligninolytic bacteria are considered a major source of ligninolytic enzymes, which are widely used in a...  相似文献   
996.

The study evaluated the hepatoprotective activity of plant extracts of cinnamon and glycyrrhizin in distinct dosage ways to minimize the oxidative stress induced by carbon tetrachloride (CCl4) in BALB/cJ inbred albino mice. Fifteen albino mice were divided into five groups, each group containing three mice. Group A was referred as positive control while group B, C, D and E were injected intraperitoneally with 1 mL/kg body weight of CCl4 twice a week for 1 month. Group C and D were treated orally with isolated extracts of cinnamon @50 mg/kg and glycyrrhizin @50 mg/kg respectively on daily basis for 1 month. However, group E was treated orally with combination dose of cinnamon @50 mg/kg + glycyrrhizin @50 mg/kg body weight. The increase in the levels of alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP), triglyceride (TG), malondialdehyde (MDA) and glucose were recorded in CCl4 induced liver injury in mice while there is decrease in the levels of total protein (TP), reduced glutathione (GSH), Superoxide dismutase (SOD) and catalase (CAT) in CCL4 intoxicated mice. Isolated therapy of plant extracts of cinnamon and glycyrrhizin decreased the levels of ALT, AST, ALP, MDA, TG and glucose whereas increase in TP, GSH, SOD and CAT was observed in plant extracts treated mice. The best restoration of all the above said parameters near to control was observed in group of mice treated with combination dose of cinnamon and glycyrrhizin @50 mg/kg. Therefore, the present study declared the antioxidative, anti-inflammatory and hepatoprotective activity of standardized extracts of cinnamon and glycyrrhizin and their potent defensive property.

  相似文献   
997.
In recent years, there has been a move away from the medical model of care for people with borderline personality disorder, as hospital admission comes with a number of risks and potential adverse consequences. Although long‐term outpatient‐based therapy is successful, this may not be an option for those whose condition is in need of stabilisation. Brief admission for crisis intervention has been successful and is now widely used; however, research that examines both the staff and clients’ perceptions of a dedicated programme is lacking. Open Borders is a residential recovery‐oriented programme that provides brief admission, respite, and phone coaching for people with borderline personality disorder who are heavy users of the public mental health system. In this paper, the authors report the perspectives of clients and staff of the Open Borders programme obtained through semi‐structured interviews. Thematic analysis of client and staff perspectives identified four common themes: ‘Benefits of the programme’, ‘Enhanced client outcomes’, ‘Impact of the physical environment’, and ‘Ways of enhancing service delivery’. In addition, analysis of the staff perspectives included the theme ‘Emotional impact on staff’. Benefits of the programme included the small supportive team approach, flexibility of the staff to spend time with the clients to tailor care, and the relaxed, welcoming environment. Enhanced client outcomes included a reduction in self‐harming and hospitalization and an increase in self‐efficacy. These results support the move away from the medical model and the empowerment of clients to self‐manage their symptoms while fostering hope and self‐determination.  相似文献   
998.

Background

Diabetes mellitus (DM) is a major health problem in Sudan and is a leading cause of morbidity and mortality. Dyslipidemia is a major complication of diabetes and an important risk factor for cardiovascular disease (CVD). The objective of this study was to determine the prevalence of dyslipidemia and its co-relation with the glycemic control in individuals with diabetes in River Nile State, Sudan.

Methods

Individuals with diabetes attended, Naserudin Karamalla Diabetic (NKDM) Centre, in Atbara teaching hospital during study period, who volunteered to participate were included. Only those on treatment for DM for at least one year were included. Venous samples were collected for cholesterol, triglycerides, HDL, LDL, blood glucose and Glycosylated hemoglobin. Participants were interviewed using standardized pretested questionnaire to record medical history and sociodemographic characteristics. Blood pressure, body mass index (BMI) and waist circumference were measured.

Results

A total of 188 individuals were included. The mean age was 49.5?+?13.9 and (128) 68.1% were females. Most patients were having DM for at least 3–5 years 69 (36.7%). Poor diabetes control (HbA1c >7) was recorded in 87.2%, hypercholesterolemia, hypertriglyceridemia and high LDL were identified in 36.6%, 27.7% and 26.6% respectively. In addition, HDL was low in 61.2% of patients.

Conclusion

Low HDL is a prominent feature in two thirds of individuals with diabetes, while high cholesterol and high triglyceride were seen in over one quarter.  相似文献   
999.
PURPOSE: Digital pressure on the perineum was reported to result in an increase of the rectal tone. This effect has been related to a reflex action named perineorectal reflex but was not verified. The mechanism of action of perineal pressure on the rectal tone was studied. METHODS: Eighteen healthy volunteers (mean age +/- standard deviation, 39.7 +/- 11.8 years; 10 males) were studied. The barostat system used consisted of a polyethylene balloon connected to a strain gauge and a computer-controlled, air-injection system. The balloon was introduced into the rectum, and the rectal tone was assessed by recording the balloon volume variations in response to digital pressure on the perineum. The test was repeated after individual anesthetization of perineum and rectum. It was performed again using normal saline instead of Xylocaine. RESULTS: During perineal pressure, all the volunteers exhibited rectal tone increase with a mean decrease in the balloon volume of 72.3 +/- 14.7 percent. There was no significant difference (P > 0.05) in the rectal tone response between females and males nor between young and elderly patients. The mean latency was 17.3 +/- 1.8 ms. Perineal pressure 20 minutes after individual anesthetization of perineum and rectum effected no significant rectal tone changes. The response returned after the anesthetic effect had waned. The rectal tone response after saline administration was similar to that before administration. CONCLUSION: The study has shown that rectal tone increase during digital perineal pressure represents most probably a reflex action. This was evidenced by absence of rectal tone response on individual anesthetization of the assumed two arms of the reflex arc: perineum and rectum. The perineorectal reflex may be of diagnostic significance in rectal motor disorders and has the potential to be used as an investigative tool, provided further studies are performed to prove these points.  相似文献   
1000.
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