996 resultados para Arabian Gulf


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The study assessed natural levels and patterns of genetic variation in Arabian Gulf populations of a native pearl oyster to define wild population structure considering potential intrinsic and extrinsic factors that could influence any wild structure detected. The study was also the first attempt to develop microsatellite markers and to generate a genome survey sequence (GSS) dataset for the target species using next generation sequencing technology. The partial genome dataset generated has potential biotechnological applications and for pearl oyster farming in the future.

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The population biology and status of the painted sweeplips (Diagramma pictum) and spangled emperor (Lethrinus nebulosus) in the southern Arabian Gulf were established by using a combination of size-frequency, biological, and size-at-age data. Transverse sections of sagittal otoliths were characterized by alternating translucent and opaque bands that were validated as annuli. Comparisons of growth characteristics showed that there were no significant differences (P>0.05) between sexes. There were well defined peaks in the reproductive cycle, spawning occurred from April to May for both species, and the mean size at which females attained sexual maturity was 31.8 cm fork length (LF) for D. pictum and 27.6 cm (LF) for L. nebulosus. The mean sizes at first capture (21.1 cm LF for D. pictum and 26.4 cm LF for L. nebulosus) were smaller than the sizes for both at first sexual maturity and those at which yield per recruit would be maximized. The range of fishing-induced mortality rates for D. pictum (0.37−0.62/yr) was substantially greater than the target (Fopt=0.07/yr) and limit (Flimit=0.09/ yr) estimates. The range of fishing-induced mortality rates for L. nebulosus (0.15/yr to 0.57/yr) was also in excess of biological reference points (Fopt=0.10/yr and Flimit=0.13/yr). In addition to growth overfishing, the stocks were considered to be recruitment overfished because the biomass per recruit was less than 20% of the unexploited levels for both species. The results of the study are important to fisheries management authorities in the region because they indicate that both a reduction in fishing effort and mesh-size regulations are required for the demersal trap fishery.

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Regression coefficient value (b) of the length-weight relation of Epinephelus chlorostigma was registered as 2.6383, which is significantly (p<0.01) less than the hypothetical value (3). This coefficient of E. areolatus was registered as 2.9500, a value close to 3. The correlation coefficients (r) were registered as 0.9725 and 0.9837 for E. chlorostigma and E. areolatus, respectively, which show a good relationship between the two parameters.

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A comparative study was carried out between the two biggest creeks along the Arabian Gulf coast of the United Arab Emirates to evaluate impacts of sewage and industrial effluents on their hydrochemical characteristics. Surface and bottom water samples were collected from Abu Dhabi and Dubai creeks during the period from October 1994 to September 1995. The hydrochemical parameters studied were: temperature (21.10-34.00°C), salinity (37.37-47.09%), transparency (0.50-10.0 m), pH (7.97-8.83), dissolved oxygen (1.78-13.93 mg/l) and nutrients ammonia (ND- 13.12,ug-at N/1), nitrite (ND-6.66 ,ug-at N/1), nitrate (ND- 41.18 ,ug-at N/1), phosphate (ND- 13.06 ,ug-at P/1), silicate (0.68-32.50 ,ug-at Si/1), total phosphorus (0.26- 21.48 ,ug-at P/1), and total silicon (0.95- 40.32 ,ug-at Si/1). The present study indicates clearly that seawater of Abu-Dhabi Creek was warmer (28.l2°C) than Dubai (27.56°C) resulting in a higher rate of evaporation. Owing to more evaporation, salinity levels showed higher levels at Abu Dhabi (43.33%) compared to Dubai (39.03%) seawater. The study also revealed higher secchi disc readings at Abu Dhabi Creek (4.68 m) as compared to Dubai Creek (2.60 m) suggesting more transparency at Abu Dhabi Creek. Whereas, seawater of Dubai exhibited higher levels of pH (1.03 times), and dissolved oxygen (1.05 times) than Abu Dhabi seawater due to an increase in productivity. Meantime, seawater of Dubai showed higher tendency to accumulate ammonia (8.22 times), nitrite (10.93 times), nitrate (5.85 times), phosphate (10.64 times), silicate (1.60 times), total phosphorus (3.19 times), and total silicon (1.54 times) compared to Abu Dhabi seawater due to the enrichment of seawater at Dubai with domestic sewage waters which has distinctly elevated the levels of the nutrient salts particularly in inner-most parts of the creek leading to eutrophication signs. The changes occurred in the receiving creek water of Dubai as a result of waste-water disposal that have also reflected on the atomic ratios of nit: Effect of pollution rogen: phosphorus: silicon.

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This paper deals with the levels and distributions of nutrient salts in the United Arab Emirates waters. Water samples were collected bimonthly during 1994-1995 from the marine environment of the United Arab Emirates, which extends more than 800km along the Arabian Gulf and the Gulf of Oman. Concentrations of ammonium, nitrite, nitrate, phosphate, silicate, as well as total concentrations of total dissolved nitrogen, phosphorus, and silicon in the area were scattered in the ranges: (ND-6.32; mean: 0.84 µg-at N/l), ND-3.02; mean: 0.42 µg-at N/l), (ND-10.88; mean: 1.18 µg-at N/1), (ND-4.22; mean: 0.62 µg-at P/l), (1.14-28.80; mean: 6.52 µg-at Si/l), (1.52-39.58; mean: 12.28 µg-at N/l), (0.40-4.98; mean: 1.07 µg-at P/l), and (2.77-44.74; mean: 13.02 Si/l) respectively. Of inorganic nitrogen species, ammonium was the highest in the Arabian Gulf waters and nitrate was the highest at the Gulf of Oman. The dissolved inorganic nitrogen total species, phosphate and silicate amounted to 16.4, 47.6, 56.5% respectively, of the concentrations of nitrogen, phosphorus and silicon in the Arabian Gulf and 22.6, 64.4, 44.9% respectively, in the Gulf of Oman, indicating that more than 80% of nitrogen was present in organic forms. Distributions of nutrient in the two regions were higher in the summer season and lower in the winter season due to the oxidation of organic materials. Regional distributions revealed higher values for nitrite (1.3 times), nitrate (2.8 times), phosphate (2.2 times), total dissolved nitrogen (1.3 times), total dissolved phosphorus (1.6 times), and total dissolved silicon (1.3 times) in the Gulf of Oman compared to the Arabian Gulf, indicating more oligotrophic conditions at the Arabian Gulf Whereas no distinct patterns of distribution were observed in the Arabian Gulf waters, an increase in the seaward direction was measured at the Gulf of Oman. Vertical distributions indicated a general increase with depth in the two regions. The mean ratios for total concentrations of phosphorus, nitrogen, and silicon in the Arabian Gulf (1: 11.6: 12.6) and the Gulf of Oman (1: 10.1: 11.8) were lower than the Redfield ratio.

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From the distribution of oceanographic data (temperature and salinity) in both Arabian Gulf and Gulf of Oman, the steric components (thermal, haline and steric heights) are calculated for the upper 50m layer during different seasons. The analysis reveals relevant evidence, that temperature variations (thermal component) play a role in the fluctuations of sea level within the investigated area. The salinity variations (haline component) is only significant near the entrance. The sea level variations due to density (steric component) is low during winter and spring and high during summer and autumn. The steric height is always lower in the northern and central regions of Arabian Gulf and higher in eastern region of Arabian Gulf and in the Gulf of Oman, i.e. the surface water must flow from the Gulf of Oman to the Arabian Gulf. The steric sea level gradient around the Strait of Hormuz are 0.04 cm/km in winter, 0.04 cm/km in spring, and 0.025 cm/km in summer and 0.014 cm/km in autumn.

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Cette thèse contribue à l'état actuel des connaissances sur la compatibilité des nouveaux bâtiments avec les environnements urbains historiques. Elle suit un mode de présentation classique: Introduction, Revue de Littérature, Méthodologie, Résultats, Discussion et Conclusion. Le problème étudié est le manque d'orientation pour intégrer les processus de développement et de sauvegarde dans les contextes établis. La littérature récente révèle que les règles de préservation, aussi appelées normes et lignes directrices, ne peuvent pas garantir une relation compatible entre une intervention et son milieu. La pensée contemporaine dans le domaine de la conservation et de la gestion du patrimoine invite donc l’exploration d'autres moyens pour lier la nouvelle architecture à l'ancienne. Ainsi, le présent projet de recherche explore une approche alternative aux règles de préservation en vue d’atteindre le but de nouveaux bâtiments compatibles et d’améliorer la prise de décision fondée sur les valeurs. Pour produire des résultats spécifiques et convaincants, un cas a été sélectionné. Celui-ci est une ville dans la région du Golfe Arabe : la Ville de Koweït. Le résultat principal est le développement d’une approche, mise en œuvre en posant des questions approfondies sur le lieu, la conception et la construction des nouveaux bâtiments. Les questions suggérées dans la thèse mettent l’accent sur les valeurs patrimoniales et les choix de conception afin de permettre un changement réfléchi au sein des environnements urbains historiques. Elles aident aussi à évaluer les nouvelles propositions de projets au cas par cas. Pour démontrer comment cette approche pourrait être présentée et utilisée par les requérants et les évaluateurs, un modèle théorique est proposé. Ce modèle a ensuite été discuté avec des professionnels locaux et internationaux qui ont identifié ses forces et ses limites. En conclusion, l’ensemble des résultats montre que la mise à disposition de règles et / ou de questions approfondies n’est pas une solution satisfaisante puisqu’il y a d'autres enjeux importants qui devraient être abordés: comment appliquer l'orientation efficacement une fois qu’elle a été créée, comment développer la compétence liée à la prise de décision fondée sur les valeurs et comment insérer la conservation du patrimoine dans la mentalité du gouvernement local et des communautés. Lorsque ces enjeux seront traités, le patrimoine pourra devenir partie intégrante du processus de planification, ce qui est le but ultime. Enfin, cinq axes de recherche sont recommandés pour poursuivre l’exploration des idées introduites dans cette étude.

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Health professionals need to be cognizant of the varying perceptions of health shared by people from different religious, sociocultural, and linguistic backgrounds to deliver culturally sensitive health care. In this qualitative study, the authors used semistructured interviews to provide insight into how 10 older Arabian Gulf Muslim persons understand and perceive health and illness with emphasis on the role of Islam in formulating health behaviors. Participants' views were strongly influenced by their religious convictions. Good health was equated with the absence of visible disease, with participants demonstrating limited understanding of silent or insidious disease. They attended doctors for treatment of visible disease rather than seeking preventive health care for diseases such as hypertension, diabetes, and hyperlipidemia. Building oil the results from this study could help inform both health service planners and providers to improve the appropriateness, relevancy, and effectiveness of aged care services for these individuals.

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The reduction in the useful-service life of reinforced concrete construction in the Arabian Gulf is attributed to reinforcement corrosion. While this phenomenon is primarily related to chloride ions, the concomitant pressure of sulfate salts may accelerate the deterioration process. Another factor which might influence reinforcement corrosion is the elevated ambient temperature. While few studies have been conducted to evaluate the individual effect of sulfate contamination and temperature on chloride binding and reinforcement corrosion, the synergistic effect of these factors on concrete durability, viz.-a-viz., reinforcement corrosion, needs to be evaluated. Further, the environmental conditions of the Arabian Gulf are also conducive for accelerated carbonation. However, no data are available on the concomitant effect of chloride-sulfate contamination and elevated temperature on the carbonation behaviour of plain and blended cements.This study was conducted to evaluate the conjoint effect of chloride-sulfate contamination and temperature on the pore solution chemistry and reinforcement corrosion. The effect of chloride-sulfate contamination and elevated temperature on carbonation in plain and blended cements was also investigated. Pore solution extraction and analysis, X-ray diffraction, differential thermal analysis, scanning electron microscopy, DC linear polarization resistance and AC impedance spectroscopy techniques were utilized to study the effect of experimental parameters on chloride binding, reinforcement corrosion and carbonation.The results indicated that the concomitant presence of chloride and sulfate salts and temperature significantly influences the durability performance of concrete by: (i) decreasing the chloride binding, (ii) increasing reinforcement corrosion, and (iii) accelerating the carbonation process. To avoid such deterioration, it is advisable to minimize both chloride and sulfate contamination contributed by the mixture ingredients. Due to the known harmful role of sulfate ions in decreasing the chloride binding and increasing reinforcement corrosion, limits on allowable sulfate contamination in concrete should also be established.

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This paper examines shifting approaches to urban sustainability in the Arabian Gulf by focusing on the issue of air conditioning and thermal comfort. It considers the recent foregrounding of tradition and heritage within the arena of mega-project development in Qatar, using the Msheireb Downtown Doha Project as an example of a wider regional trend around urban sustainability. Through its focus on air conditioning, the paper draws on Appadurai’s recent critique of design singularity to examine built environment sustainability in relation to the indoor comfort norms and practices, for both bodies and objects, which are now well established across the Gulf region.

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This short essay, built on a foundation of more than a decade of fieldwork in the hydrocarbon-rich societies of the Arabian peninsula, distills a set of overarching threads woven through much of that time and work. Those threads include a discussion of the social heterogeneity of the Gulf State citizenries, the central role of development and urban development in these emergent economies, the multifaceted impact of migrants and migration upon these host societies, and the role of foreign 'imagineers' in the portrayal of Gulf societies, Gulf values, and Gulf social norms.

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The United Arab Emirates (UAE) is part of the geographic region known as the Middle East. With a land mass of 82,000 square kilometres, predominantly desert and mountains it is bordered by Oman, Saudi Arabia and the Arabian Gulf. The UAE is strategically located due to its proximity to other oil rich Middle Eastern countries such as Kuwait, Iraq, Iran, and Saudi Arabia. The UAE was formed from a federation of seven emirates (Abu Dhabi, Dubai, Sharjah, Ras Al Khaimah, Ajman, Fujuriah, and Um Al Quain) in December 1971 (Ras Al Khaimah did not join the federation until 1972) (Heard-bey, 2004, 370). Abu Dhabi is the political capital, and the richest emirate; while Dubai is the commercial centre. The majority of the population of the various Emirates live along the coast line as sources of fresh water often heavily influenced the site of different settlements. Unlike some near neighbours (Iran and Iraq) the UAE has not undergone any significant political instability since it was formed in 1971. Due to this early British influences the UAE has had very strong political and economic ties with first Britain, and, more recently, the United States of America (Rugh, 2007). Until the economic production of oil in the early 1960’s the different Emirates had survived on a mixture of primary industry (dates), farming (goats and camels), pearling and subsidies from Britain (Davidson 2005, 3; Hvit, 2007, 565) Along with near neighbours Kuwait, Bahrain, Oman, Qatar and Saudi Arabia, the UAE is part of the Gulf Cooperation Council (GCC), a trading bloc. (Hellyer, 2001, 166-168).

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Objectives Studies from different parts of the world have indicated that the impact of road traffic incidents disproportionally affects young adults. Few known studies have been forthcoming from Arabian Gulf countries. Within Oman, a high proportion of the population is under the age of 20. Coupled with the drastic increase of motorization in recent years there is a need to understand the state of road safety among young people in Oman. The current research aimed to explore the prevalence and characteristics of road traffic injuries among young drivers aged 17-25 years. Methods Crash data from 2009-2011 was extracted from the Directorate General of Traffic, Royal Oman Police (ROP) database in Oman. The data was analyzed to explore the impact of road crashes on young people (17-25 years), the characteristics of young driver crashes and how these differ from older drivers and to identify key predictors of fatalities in young driver crashes. Results Overall, young people were over-represented in injuries and fatalities within the sample time period. While it is true that many young people in crashes were driving at the time, it was also evident that young people were often a victim in a crash caused by someone else. Thus, to reduce the impact of road crashes on young people, there is a need to generally address road safety within Oman. When young drivers were involved in crashes they were predominantly male. The types of crashes these drivers have can be broadly attributed to risk taking and inexperience. Speeding and night time driving were the key risk factors for fatalities. Conclusion The results highlight the need to address young driver safety in Oman. From these findings, the introduction of a graduated driver licensing system with night time driving restrictions could significantly improve young driver safety.

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A new species of the copepod genus Tortanus (Atortus) (Copepoda: Calanoida), T. (A.) insularis, is described from the coastal region of Rodrigues Island, Mauritius, an isolated island in the south-western Indian Ocean. This new species can be assigned to an Indian element, the recticauda species group, in the Indo-West Pacific recticauda species complex. It exhibits the closest relationship to T. (A.) recticauda recorded from the southern Red Sea and Arabian Gulf, rather than the more closely distributed T. (A.) capensis, recorded from off South Africa.