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This work presents techno-economic assessment and optimization results for wind power implementation. The results constitute an attempt to provide recommendations on optimal design configurations and operating conditions for future possibilities of installations in Kuwait, where the wind speed is at maximum levels at high altitudes during the early daytime and late nighttime, whereas in the afternoon, the wind speed reaches its maximum at low altitudes. This cyclic behavior indicates that the wind speed and direction change in a predictable pattern, benefiting wind power generation. The techno-economic assessment and optimization are performed for multi-row design configurations of power plants. The selection using an optimal method comes through evaluating 2220 configurations, from which 60 optimal configurations are determined for different variations of the number of rows in the wind power plant (N r) based on the minimization criterion of the Levelized Cost of Electricity (LCOE). The optimal configurations have optimal wind power plant layout angle (θ plant). Some of the main findings are as follows:(i) the N r and θ plant values impact the LCOE, wake losses, performance ratio, capacity factor, and annual gross energy. (ii) The wind power density is calculated to be 289 W/m2, (iii) June and July have high levels of generation, wind speed, temperature, and humidity, (iv) there exists an exponential relation between the installed cost per watt and N r. (v) The present value of annual energy, net present value (annual costs), annual energy, and annual gross energy have increasing linear trends as N r increases, and (vi) the optimal configurations require a power purchase agreement price of at least 7.03 cent/kWh to make a positive return on investment. • N r and θ plant impact the LCOE, wake losses, and other performance parameters. • 60 configurations with optimal θ plant based on the minimum LCOE are identified. • Wind shear and power density values are calculated. • June and July have high-level generation, wind speed, temperature, and humidity. • LOESS analyses confirm prevailing wind with a consistent northwest component. [ABSTRACT FROM AUTHOR]

The Concentrating Solar Power - Parabolic Trough (CSP-PT) technology with dry-cooled condenser system is an alternative option for arid climate locations such as Kuwait. In this work, the performance of various CSP-PT design configurations is evaluated, including 19 configurations that have been reported in the literature as being optimal. These have optimal Solar Multiple (SM) values based on the lowest Levelised Cost of Electricity (LCOE). Furthermore, an evaluation of CSP-PT with Thermal Energy Storage (TES), including wind power potential, is performed. It is revealed that coinciding peaks of electrical load, solar, and wind resources promote co-generation from CSP-PT/TES and wind power with significant benefits. Also, the wind speed is found to be at maximum levels at high altitudes in the early daytime and late nighttime. Whereas in the afternoon, it reaches maximum values at low altitudes. The calculated wind shear exponent is between 0.14-0.18 and showing a cyclic behavior. Such findings promote mega-scale wind power generation. From the techno-economic assessment, it is concluded that the SM value for optimal CSP-PT/TES configuration increases with an increasing number of full load hours of storage (N h TES). In addition, the N h TES has significant effects on the annual energy generation, capacity factor, and LCOE. However, the impact of N h TES on the annual overall plant efficiency is insignificant. Furthermore, the optimal SM and lowest LCOE values are determined. Also, the periods of 24 h continuous electricity generation from CSP-PT/TES without fossil backup have been identified. • Coinciding peaks of load, solar, and wind resources promote co-generation. • Wind speed increases in early-day/late-night at high altitudes and in afternoon at low altitudes. • α is calculated to be 0.14–0.18 and showing cyclic behavior in the wind resource. • N h TES has maximal effects on E ele , a , CF, and LCOE but minimal effect on η overall. • Periods of 24 h generation from CSP-PT/TES without fossil backup are identified. [ABSTRACT FROM AUTHOR]

The need for continuing education in management development was investigated with special reference to Kuwait University, and the nature and practice of continuing education, its purposes, problems and its evaluation in relation to management development were reviewed. It was concluded that education supports the creation of new social relationships and that continuing education must remedy the failures of formal education, and the existing distortion of socioeconomic and cultural aspects of society. Recommendations are made to facilitate achievement of these goals. [ABSTRACT FROM AUTHOR]

This work evaluates the concentrating solar power (parabolic trough) technology for electricity generation in Kuwait. The assessment is performed on an existing plant in Spain, and the model is validated using published data. The Direct Normal Irradiance (DNI) of Spain exceeds that of Kuwait by a difference of 176.2 kWh/m 2 a , but the overall performance of the Kuwait case exceeds that of Spain. With wet cooling, the Kuwait case performance exceeds that of Spain for the annual overall plant efficiency by 2.9% and the annual efficiency of the Solar Field (SF) by 4.1%. Additionally, the annual net electricity output of the Kuwait case exceeds that of Spain by 14,534 MWh e. With dry cooling, the Kuwait case performance exceeds that of Spain for the annual overall plant efficiency by 1.1% and the annual efficiency of the SF by 3.0%. However, the annual net electricity output of the Spain case exceeds that of Kuwait by only 749.8 MWh e. The better performance of the Kuwait case is due to the DNI impact on the number of full load hours of steam turbine, ambient temperature, wind speed, and SF heat loss/dumped energy. The techno-economic assessment considered numerous design configurations utilizing dry cooling in Kuwait due to the lack of water resources. The solar multiple and the number of full load hours of storage are varied to identify optimal configurations. It is concluded that the optimal solar multiple is at 3.3 corresponding to the lowest LCOE of 15.0663 ¢ / kWh for 16 h of storage. • Design climatic conditions for CSP-PT plants in Kuwait are determined. • Effects of dry and wet cooling options on CSP-PT plant performance are examined. • Number of full load hours of steam turbine, and electricity output are evaluated. • Water consumption, plant efficiency, and SF performance measures are estimated. • Techno-economic parameters for 50 MW CSP-PT plants are calculated and compared. [ABSTRACT FROM AUTHOR]

Aims: To audit our experience in management of vascular trauma between 1992 and 2000. Methods: Retrospective review of all patients treated for vascular trauma. Results: One hundred and fifty-five patients with vascular injuries were managed during the period 1992–2000. 30.3 per cent (n = 47) were stab wounds and 23.3 per cent (n = 36) were due to RTA. 21 neck injuries (13.5 per cent), six chest injuries and 10 patients with abdominal vascular injuries. Of the latter, three patients died on the operating table because of exanguination. 118 patients had limb injuries. 49 (32 per cent) were upper limb and 69 (44.5 per cent) were lower limb injuries. Of the latter, two patients presented with bilateral crush injuries, revascularization of only one limb was performed in each case. The other limb was severely traumatized beyond repair. Autogenous vein was used in the majority of cases for revascularization. All 49 upper limb revascularization were successful. Of the 69 revascularized lower limbs, four grafts failed: two within 24 h due to poor run-off and extensive soft tissue loss, respectively, the other two failed after 6 months due to progressive atherosclerosis, HTN, DM and Buerger′s disease, respectively. One patient died on the tenth postoperative day due to PE with patent graft. The long-term patency rate of revascularized limbs at a median follow up of (4.4 ± 2 years) was 96 per cent. The amputation rate was 1.3 per cent and the mortality rate of all vascular traumas in this report was 2.5 per cent. Conclusions: The use of autogenous vein graft is associated with good results. Progression of peripheral vascular disease and diabetes are risk factors for graft failure. [ABSTRACT FROM AUTHOR]

Background and Study Aims: Chronic infection caused by Helicobacter pylori (H. pylori) is associated with chronic gastritis, peptic ulcer disease, and gastric cancer. Eradication of H. pylori reduces morbidity of chronic gastritis and incidence of gastric cancer in high-risk population. We aimed at testing the efficacy of clarithromycin-based triple therapy and bismuth-based quadruple therapy for eradicating H. pylori in patients with chronic gastritis in Kuwait., Patients and Methods: A total of 218 dyspeptic patients from different countries who were proved to have chronic gastritis by endoscopy and gastric biopsy were enroled. All of them were naïve to H. pylori eradication therapy. They were randomised into two groups: group A, received triple therapy (omeprazole, amoxicillin, and clarithromycin) for 10days; and group B, received quadruple therapy (omeprazole, bismuth subcitrate potassium, tetracycline, and metronidazole) for 10days. All patients were tested for eradication of H. pylori by carbon-13 urea breath test 4weeks after treatment., Results: Total response rate of eradication therapy in both groups was 77.5% (n=169). However, group B (n=100) had a higher eradication rate (88%) than group A (n=118) (68.6%). H. pylori eradication rate was significantly higher in males (84.2%) than females (70.2%) in both groups (p<0.01). There were no differences in eradication rates with regard to median age or nationality., Conclusion: Bismuth-based quadruple therapy is more effective as a first-line therapy than clarithromycin-based triple therapy for eradicating H. pylori in patients with H. pylori-related chronic gastritis in Kuwait., (Copyright © 2015 Arab Journal of Gastroenterology. Published by Elsevier B.V. All rights reserved.)

Objective: Ulcerative colitis (UC) is generally considered a disease of the Caucasian populations in developed countries, but its incidence is increasing rapidly in many developing countries, including the Middle East. The objective of this study was to determine the clinical epidemiology of UC in Arabs., Material and Methods: This cross-sectional medical record-based descriptive study collected sociodemographic and clinical information on 182 Arab patients with UC in Kuwait. Age at diagnosis, extent and severity of disease were determined according to the Montreal classification. results: Among the 182 patients, 91 (50.0%) were males. The median age at diagnosis was 28.5 years. Family history of UC was reported by 26 (14.3%) patients. The extent of the disease was limited to the rectum in 34 (18.7%) patients, left sided in 67 (36.8%) and pan colitis in 81 (44.5%). At the time of inclusion in the study, 127 (69.8%) patients were in clinical remission, 53 (29.1%) had mild-to-moderate disease and 2 (1.1%) had severe colitis. Younger age at diagnosis and non-smoking were associated with more extensive colitis. The majority of patients were treated with mesalamine, steroids and immunomodulators, while biologic therapy and surgery were needed in 5% and 4% of the patients, respectively., Conclusions: UC presents more commonly at younger age among Arabs in Kuwait. Extensive disease at presentation is associated with younger age at diagnosis and absence of tobacco smoking. There also appears to be less need for surgery and biologic therapy for the disease in this population.

Background: There has been a remarkable increase in the incidence of Crohn's disease (CD) among Arabs in recent years. We conducted this study to determine the clinical epidemiology of CD in Kuwait., Methods: Sociodemographic and clinical information was collected for a continuous series of 206 Arab patients with CD and age at diagnosis and location and behavior of disease was determined according to the Montreal Classification., Results: Among the 206 patients, 100 (48.5%) were males and 106 (51.5%) females. The mean age at diagnosis (±SD) was 21.9 ± 10 years. Family history of CD was reported by 39 (18.9%) patients. The disease was limited to the ileum in 115 (55.8%) patients, whereas in 28 (13.6%) it involved the colon and in 63 (30.6%) it involved both the ileum and colon. The behavior of the disease was nonstricturing, nonpenetrating in 146 (70.9%) patients, whereas 49 (23.8%) had stricturing and 11 (5.3%) penetrating disease. Perianal disease was present in 41 (19.9%) patients. In the multivariate analysis, the use of biologic therapy and duration of the disease for ≥6 years were significantly associated with the presence of perianal disease, and the need for surgery was significantly associated with stricturing and penetrating disease behavior., Conclusions: CD among Arabs is equally common in males and females, presents at a relatively younger age, and in about half of the patients is limited to the small bowel. These features may indicate an underlying genetic predisposition for the disease in this population, which needs further investigation., (Copyright © 2011 Crohn's & Colitis Foundation of America, Inc.)

Objective: To evaluate the outcome of children with Hodgkin's disease over a period of 10-years from a single institution in Kuwait., Methods: Sixty-three children with previously untreated Hodgkin's disease, who were diagnosed at the Pediatric Oncology Unit of Kuwait Cancer Control Centre, Shuwaikh, Kuwait from January 1998 to December 2007 were included in the study. All cases were proved by histopathology, and staging was carried out according to the Ann Arbor system., Results: Our series included 37 (59%) males and 26 (41%) females with a median age of 10 years (range 3-15 years). B symptoms were present in 20 (32%) children. Bulky disease was noted in 28 (44%) children, with stages III in 8 (13%) and IV in 12 (19%) children. Chemotherapy was administered as a primary treatment in 63 children. The median number of chemotherapy cycles given was 6 (range 2-8). Radiotherapy was used in 40 (63%) children. Grade III hematological toxicity was observed in 23 (37%) and grade IV in 14 (22%) children. Hypothyroidism was observed in 20 (32%) children. Fifty-five children achieved a complete remission (87%) and 2 children achieved a partial remission (3%) with an overall response rate of 90%. Three children achieved a progressive disease (5%) and response could not be evaluated in 3 (5%) children. At a median follow-up of 67 months (5.5 years), the overall survival was 91%., Conclusion: With moderate toxicity, combined modality therapy is effective in the treatment of childhood Hodgkin's disease.

Objective: The aim of this study was to investigate the left-ventricular (LV) mass-adjusted association between low heart rate variability (HRV) and atherosclerotic cardiovascular disease (ASCVD) among hemodialysis patients in Kuwait., Subjects and Methods: One hundred and eight patients were enrolled in the study. HRV time domain measures were obtained by 48-hour Holter monitoring, including the standard deviation of all R-wave-to-R-wave (RR) intervals (SDNN), standard deviation of all 5-min averaged intervals (SDANN), HRV triangular index (HRV-TI), percent of adjacent RR intervals differing by >50 ms (pNN50), and root mean square of sums of squares of all differences (rMSSD). Left ventricular ejection fraction (LVEF) and LV mass index (LVMI) were measured by M-mode echocardiography. Comorbidity was assessed using medical record review. Prevalent ASCVD was defined as coronary artery, cerebrovascular, or peripheral vascular disease., Results: Prevalence of ASCVD, LV hypertrophy, and LVEF <40% were 56, 59, and 10%, respectively. The SDANN was negatively associated with ASCVD (-20 ms; p = 0.003), LV systolic dysfunction (-20 ms; p = 0.001), elevated LVMI (-20 ms; p = 0.002), hypertension (-34 ms; p = 0.01), and diabetes (-20 ms; p = 0.001). After adjustment for hypertension and LVMI using logistic regression, ASCVD was associated with the lowest quartile of SDANN (OR = 4.3, p = 0.009), HRV-TI (OR = 3.3, p = 0.03), and SDNN (OR = 2.3, p = 0.10). These associations persisted after adjusting for LVEF., Conclusion: In dialysis patients, low HRV indices were strongly associated with prevalent ASCVD, independent of LVMI and LVEF. The interrelationships among HRV, diabetes, hypertension, and LVMI should be addressed in studies of HRV and ASCVD., (Copyright 2009 S. Karger AG, Basel.)

Objective: To compare the validity of a careful clinical examination with venous Doppler studies in the management of patients presenting with varicose veins., Subjects and Methods: Ninety-five consecutive patients presenting with varicose veins from September 1998 to August 1999 were included in this study. Of the 95 patients, 52 were males and 43 females. Eighty-four were expatriate laborers and 11 Kuwaiti nationals. Seventy-one were active workers under the age of 30. All of the patients underwent a full clinical examination for varicose veins, and a management plan was developed for each patient prior to Doppler venous study. The results of the Doppler studies were then compared with the clinical examination results, and the management plan was changed, if necessary, based on the Doppler results., Results: Both clinical and Doppler examinations were equally effective in diagnosing primary varicose vein and identifying sites of venous incompetence. A family history for varicose veins was found in 21% and standing for a long period of time was a risk factor in 51% patients. The most common symptoms were pain and heaviness. Doppler study findings were useful in changing the management plan of 14 (15%) patients, 6 with recurrent varicose vein and 8 obese patients with chronic venous insufficiency. The majority of the patients (n = 82) benefited from surgery and were free of symptoms., Conclusion: This prospective study demonstrated that detailed clinical examination was sufficient to diagnose most patients suffering from primary varicose veins. Doppler vascular studies were useful in changing the treatment modality for those presenting with recurrent varicose vein or obese patients with signs and symptoms of chronic venous insufficiency with no clinically clear varicosity., (Copyright 2004 S. Karger AG, Basel)

Objectives: To audit the management of vascular trauma in Kuwait, 1992-2000., Design: Retrospective open study., Setting: Vascular surgery unit, teaching hospital, Kuwait., Subjects: 155 patients with vascular injuries, most of which (n = 118) involved the extremities. 21 had neck injuries, 10 abdominal, and 6 chest., Intervention: Revascularisation usually using the long saphenous vein in addition to direct repair or end-to-end anastomosis., Main Outcome: Morbidity (amputation) and mortality., Results: Four lower limb grafts failed, two of which (2/69, 3%) required amputation. Overall, four patients died (3%), one of pulmonary embolism and 3 of severe injuries to major abdominal vessels. 3/10 patients with abdominal vascular trauma died. Mean (SD) follow up period was 4.4 (2) years., Conclusions: Civilian violence has increased in Kuwait. Vascular trauma to abdominal vessels is associated with high mortality. Autogenous saphenous vein forms an excellent conduit for revascularisation.

The biopsy slides and clinical data on 244 patients who underwent percutaneous renal biopsies in the last 4 years in Kuwait were retrospectively reviewed. The data were analysed to show a correlation between clinical presentation and histological findings. We noted a high incidence of membranoproliferative glomerulonephritis (MPGN) presenting as nephrotic syndrome in association with schistosomal infection, an endemic disease in many of the neighbouring countries. Lupus nephritis was also observed at a relatively increased incidence compared with the West. On the other hand, amyloidosis and IgA nephropathy were less common, 5% for each.