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Analysis and Comparison of Trends in Extreme Temperature Indices in Riyadh City, Kingdom of Saudi Arabia, 1985–2010  [PDF]
Ali S. Alghamdi,Todd W. Moore
Journal of Climatology , 2014, DOI: 10.1155/2014/560985
Abstract: This study employed the time series of thirteen extreme temperature indices over the period 1985–2010 to analyze and compare temporal trends at two weather stations in Riyadh city, Saudi Arabia. The trend analysis showed warming of the local air for the city. Significant increasing trends were found in annual average maximum and minimum temperatures, maximum of minimum temperature, warm nights, and warm days for an urban and a rural station. Significant decreasing trends were detected in the number of cool nights and cool days at both stations. Comparison of the trends suggests that, in general, the station closer to the city center warmed at a slower rate than the rural station. Significant differences were found in a lot of the extreme temperature indices, suggesting that urbanization and other factors may have had negative effects on the rate of warming at the urban station. 1. Introduction A better understanding of trends in local extreme temperature has potential benefits to many practical problems. Increasing extremely high temperatures, for example, directly affect energy consumption [1]. In summer 2010, which was the warmest season in Saudi Arabia’s record with temperatures reaching 52°C in Jeddah city, eight power plants throughout Saudi Arabia were forced to shut down, resulting in a loss of power in several cities [2], leaving people exposed and vulnerable to the extreme temperature. If observed trends indicate that such extreme temperatures are becoming more frequent, energy providers may be able to adapt their electricity supply to minimize the likelihood of widespread power outage. Evidence that localized high temperatures are becoming less frequent, on the other hand, along with assessment of possible causes of the cooling, can be used to develop and implement urban planning strategies to mitigate local- and larger-scale warming [3–5]. Multiple recent studies have been dedicated to gaining a better understanding of mean and extreme temperature patterns and trends in Saudi Arabia (e.g., [2, 6–12]). One study [7] reported that annual mean air temperature in Saudi Arabia increased at an average rate of 0.60°C?decade?1 over the period 1978–2009 and another one [8] showed that the increasing trend was robust across the seasons, although the rate of change did vary seasonally. Annual maximum and minimum temperature also increased over the period 1978–2009 [8]. Other extreme temperature indices, such as extremely hot days (maximum temperature >90th percentile), warm spells (6 consecutive days when maximum temperature >90th percentile), and
The Global Youth Tobacco Survey: 2001–2002 in Riyadh region, the Kingdom of Saudi Arabia
Al-Bedah AM,Qureshi NA
Substance Abuse and Rehabilitation , 2011,
Abstract: Abdullah Mohammed Al-Bedah1, Naseem Akhtar Qureshi21Arabian Center for Tobacco Control, 2General Administration for Medical Research and Mental Health and Social Services, Ministry of Health, Riyadh, Saudi ArabiaBackground: Tobacco use is a major public health problem, and its prevalence is globally increasing, especially among children and adolescents.Objective: The Global Youth Tobacco Survey aimed to explore the epidemiological trends and risk factors of tobacco smoking among intermediate school boys in Riyadh region of the Kingdom of Saudi Arabia.Method: A two-stage cluster sample design was used to produce a representative sample of male students from selected schools. The participants (n = 1830) self recorded their responses on the Global Youth Tobacco Survey questionnaire.Results: Lifetime prevalence of cigarette smoking was 35%, while 13% of students currently used other tobacco products. About 16% of students currently smoked at home, and 84% of students bought cigarettes without any refusal from storekeepers. Thirty-one percent and 39% of students were exposed to secondhand tobacco smoke inside and outside the house, respectively, which was definitely or probably harmful to health as opined by 87% of participants, and 74% voiced to ban smoking from public places. Among current smokers, 69% intended (without attempt) to quit and 63% attempted (but failed) to quit during the past year. Almost an equal number of students saw antismoking and prosmoking media messages in the last month, and 28% of students were offered free cigarettes by a tobacco company representative. In schools, more than 50% of students were taught about the dangers of cigarette smoking in the last year. Smoking by parents, older brothers, and close friends, watching prosmoking cigarette advertisements, free offer of cigarettes by tobacco company representatives, perception of smoking being not harmful, and continuing smoking which can be easily quit significantly increased the odds of smoking by students.Conclusion: The common use of tobacco in school populations needs to be addressed by, among other tobacco control measures, a strict ban on cigarette selling to minors and intensive regular tobacco control campaigns involving health and religious messages.Keywords: tobacco use, secondhand tobacco smoke, environmental tobacco smoke, intermediate school boys, Global Youth Tobacco Survey, Saudi Arabia
Characterisation of MRSA strains isolated from patients in a hospital in Riyadh, Kingdom of Saudi Arabia
Monecke Stefan,Skakni Leila,Hasan Rami,Ruppelt Antje
BMC Microbiology , 2012, DOI: 10.1186/1471-2180-12-146
Abstract: Background Methicillin-resistant Staphylococcus aureus (MRSA) is spreading worldwide and poses a serious public health problem, being present in hospital settings and communities. However, from the Middle East and the Arabian Peninsula few molecular typing data on MRSA strains are currently available. In order to obtain data on the population structure of MRSA in Riyadh, Saudi Arabia, 107 clinical and environmental MRSA isolates were genotyped using a microarray-based assay. Results Five major MRSA strains from four clonal complexes were identified CC8/ST239-III (20.75%), PVL-positive as well as -negative CC22-IV (18.87% and 9.43%, respectively), PVL-positive CC30-IV (12.26%) and PVL-positive CC80-IV (17.92%). Minor strains, which accounted for less than 3% each, included CC1-IV/SCCfus, PVL-positive CC1/ST772-V, PVL-positive as well as- negative CC5-IV, CC5-IV/SCCfus, CC5-V, CC6-IV, CC45-IV, PVL-negative CC80-IV, PVL-positive CC88-IV, CC97-V and a CC9/ST834-MRSA strain. Conclusions Typing of MRSA strains from Riyadh revealed a high diversity of clonal complexes. The prevalence of the genes encoding the Panton-Valentine leukocidin was surprisingly high (54.21%), and a significant rate of resistance markers was detected also in strains considered as community-associated.
Reduction of Evaporation from Water Surfaces-Preliminary Assessment for Riyadh Region, Kingdom of Saudi Arabia
Mohammed I. Al-Saud
Research Journal of Soil and Water Management , 2013, DOI: 10.3923/rjswm.2010.5.9
Abstract: The extremely high rate of evaporation from water surfaces in arid and semi-arid regions greatly reduces optimal utilization of water reservoirs. Therefore, applying techniques to reduce evaporation greatly needed. During last decades, a large number of multipurpose dams (258) with overall design capacities of (~898 MCM), were constructed and distributed over the entire Kingdom. Hence, preserving and protecting the stored water dams reservoirs by reducing evaporation is strategic future task of the Saudi government. The present study was conducted for 7 months, from June-December 1998. Experiment was conducted in Riyadh with three US Class-A evaporation pans and a weather station. Fatty alcohol emulsion was selected to reduce the evaporation during summer months in Riyadh. Various concentrations of emulsion substance were used in different pans. First pan (H0) was filled with water without adding emulsion while in pan (H1), Fatty alcohols emulsion was added with recommended concentration of (100 g/1000 m2/day) and similarly in pan (H2) emulsion was added with double of concentration (200 g/1000 m2/day). The preliminary results of the study indicated that evaporation rate from surface water was reduced overall up to 47.2 and 50.5% in pans (H1) and (H2), respectively as compared to pan (H0).
Reduction of Evaporation from Water Surfaces-Preliminary Assessment for Riyadh Region, Kingdom of Saudi Arabia
Mohammed I. Al-Saud
Journal of Engineering and Applied Sciences , 2012,
Abstract: The extremely high rate of evaporation from water surfaces in arid and semi-arid regions greatly reduces optimal utilization of water reservoirs. Therefore, applying techniques to reduce evaporation greatly needed. During last decades, a large number of multipurpose dams (258) with overall design capacities of (~898 MCM) were constructed and distributed over the entire Kingdom. Hence, preserving and protecting the stored water dams reservoirs by reducing evaporation is strategic future task of the Saudi government. The present study was conducted for 7 months, from June-December 1998. Experiment was conducted in Riyadh with three US Class-A evaporation pans and a weather station. Fatty alcohol emulsion was selected to reduce the evaporation during summer months in Riyadh. Various concentrations of emulsion substance were used in different pans. First pan (H0) was filled with water without adding emulsion, while in pan (H1), Fatty alcohols emulsion was added with recommended concentration of (100 g/1000 m2/day) and similarly in pan (H2) emulsion was added with double of concentration (200 g/1000 m2/day). The preliminary results of the study indicated that evaporation rate from surface water was reduced overall up to 47.2 and 50.5% in pans (H1) and (H2), respectively as compared to pan (H0).
Aeropuerto Internacional King Khaled. Riyadh/Arabia Saudita  [cached]
Dahman, Mohammed N.,Tassan, Saad M.
Informes de la Construccion , 1984,
Abstract: King Khaled International Airport in Riyadh is the new access to the Saudi Arabia capital and to the heart of the Kingdom. It is the center of the national air transport and it has been planned to attend all the needs of the national and International air traffic, which has a fast growth in Riyadh zone. Its design is adapted to the Islamic traditions and harmonizes with the natural beauty of the desert. El aeropuerto internacional King Khaled de Riyadh es el nuevo acceso aéreo a la capital de Arabia Saudita y al corazón del reino. Es el centro del sistema de transporte aéreo nacional y está proyectado para atender las demandas de tráfico aéreo nacional e internacional, de crecimiento rápido, en la región de Riyadh. Su dise o se adapta a las tradiciones islámicas y armoniza con la belleza natural del desierto.
Puberty Onset Among Boys in Riyadh, Saudi Arabia
Ibrahim Al Alwan, Naila Felimban, Yasmin Altwaijri, Hani Tamim, Angham Al Mutair, Mohamed Shoukri and Waleed Tamimi
Clinical Medicine Insights: Pediatrics , 2012, DOI: 10.4137/CMPed.S4610
Abstract: Background: The ages of onset of pubertal characteristics are influenced by genetic, geographic, dietary and socioeconomic factors; however, due to lack of country-specific norms, clinicians in Saudi Arabia use Western estimates as standards of reference for local children. Aims: The aim of the Riyadh Puberty Study was to provide data on pubertal development to determine the average age of onset of pubertal characteristics among Saudi boys. Methods: Cross-sectional study among male school children in Riyadh, Saudi Arabia, in 2006, 542 schoolboys, aged 6 to 16 years old, from diverse socioeconomic levels were selected into the sample using a cluster sample design. Tanner stages were ascertained during physical examination by pediatric endocrine consultants, and also trained pediatric residents and fellows. Results: The mean age (standard deviation) at Tanner Stages 2, 3, 4, and 5 for pubic hair development of Saudi boys was 11.4 (1.6), 13.3 (1.3), 14.4 (1.0) and 15.1 (0.8) years old, respectively. For gonadal development, the mean age (standard deviation) at stages 2, 3, 4, and 5 were 11.4 (1.5), 13.3 (1.2), 14.3 (1.1) and 15.0 (0.9) years old, respectively. Conclusion: The ages of onset of pubertal characteristics, based on gonadal development, among Saudi boys are comparable to those reported in Western populations.
Toxoplasmosis in Goats in Riyadh, Saudi Arabia
S.I. Al-Mufarrej,M.F. Hussein,R.S. Aljumaah,A.R. Gar ElNabi
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2011.2779.2782
Abstract: During an outbreak of caprine abortion in a farm in Riyadh, Saudi Arabia, serum samples from 57 Aardi goats with recent history of abortion and stillbirths (herd 1) along with samples from 30 control goats without abortion history (herd 2) were analyzed for anti-Toxoplasma gondii antibodies using indirect Enzyme-Linked Immunosorbent Assay (ELISA) and Indirect Haemagglutination (IHA) tests. Antibodies against T. gondii were detected by ELISA in 63.2% of the goats in herd 1 and 50% of the control goats (herd 2). About >80% of the former goats had ELISA percent optical densities (O.D.%) ≥100 while >86% of the control goats were weakly positive with ELISA O.D. s (%) <100. IHA tests were positive in 51.7% of herd 1 versus 30% of control goats. About 78% of all IHA positive goats in herd 1 had antibody titers ranging between 1:640-1:2560 including nearly 30% with titers ranging between 1:1280-1:2560. By contrast, all IHA positive goats in herd 2 had titers ranging only between 1:80-1:160, except one goat with a titer of 1:640 and none with higher titers. IHA tests for IgM antibodies using 2-mercaptoethanol treated sera revealed IgM antibodies in 16 (28%) goats with abortion history (herd 1) and none in control goats (herd 2). Focal pathological changes were observed in the fetal brain and the placenta of some of the aborted goats. These findings strongly suggest T. gondii as the cause of abortion in herd 1.
Efficacy of hepatitis B vaccine in a cohortcommunity--based study in Riyadh and hail regions of Saudi Arabia  [cached]
Al-Faleh Faleh,Al-Jeffri Mohammed,Al-Rashed Rashed,Aref Mohammed
Saudi Journal of Gastroenterology , 2002,
Abstract: Background: Saudi Arabia used to be hyperendemic for HBV infection. Most of infection occurs in early life. HBV vaccine was, therefore, introduced in 1989 as the seventh primary immunogen of the EPI Program. This study is conducted to evaluate the efficacy of this program in Riyadh and Hail Regions. Method and Patients: A cohort follow-up study of children from Riyadh and Hail, who had been vaccinated in 1989, evaluated in 1991 and tested for HBV markers six years later. Results: The files of 303 children from Riyadh and Hail, who were investigated in 1991 retrieved and only 119, were available for testing. Fifty percent of the children have still a protective anti-HBs tittre. One vaccinated child was found to be positive for HBsAg. According to this study, the efficacy rate against HBsAg carriage is 88%. Conclusion: This study demonstrates the tremendous effect of HB vaccine on the HBV infection of Saudi children in these two regions
New additions to the scorpion fauna of Riyadh region, Saudi Arabia
Al-Asmari, AK;Al-Saief, AA;Abdo, NM;Al-Moutaery, KR;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2009, DOI: 10.1590/S1678-91992009000400003
Abstract: in this work, we present additional morphological data about the scorpion fauna of saudi arabia. this investigation was carried out in the central region (riyadh) of the country and identified existing and newly discovered scorpion species for taxonomic documentation while determining the medically important ones. the survey covered the entire riyadh region, including all major districts, and collected a total of 4,164 specimens. morphological identification of collected animals was based on identification keys. there were two species (one with a subspecies) that belonged to the family scorpionidae, namely scorpio maurus kruglovi (0.02%) and hemiscorpius arabicus (0.05%). the latter, currently, is part of the hemiscorpiidae family that had been upgraded from a subfamily. eight more species from the buthidae family were found: leiurus quinquestriatus (7.20%), androctonus crassicauda (17.24%), androctonus bicolor (64.60%), compsobuthus arabicus (3.84%), compsobuthus werneri (0.94%), buthacusyotvatensis nigroaculeatus (2.31%), buthacusleptochelys (3.24%) and orthochirus innesi (0.55%). the major locations of collection were the outskirts of riyadh city and the airport vicinity. the specimens were transported from all central region areas in 124 short trips.
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