Vol. 24 Issue 3
BraJ Mohan Misra
Desalination technologies have been well established since the mid 20th century and are widely deployed in many parts of the world having acute water scarcity problems. The energy for these plants is generally supplied in the form of either steam or electricity largely using fossil fuels. The intensive use of fossil fuels raises environmental concerns especially in relation to greenhouse gas emissions. The depleting sources and the future price uncertainty of the fossil fuels and their better use for other vital industrial applications is also a factor to be considered for sustainability. The desalination of seawater using nuclear energy is a feasible option to meet the growing demand of potable water. Over 150 reactor-years of operating experience of nuclear desalination are also in progress to confirms its technical and economic viability under country specific conditions, with technical co-ordination or support of IAEA. Recent techno-economic feasibility studies carried out by some Member States indicate the competitiveness of nuclear desalination. This paper presents the salient activities on nuclear desalination in the Agency and in the interested member states. Economic research on further water cost reduction includes investigation on utilization of waste heat from different reactor types for thermal desalination, pre-heat reverse osmosis and hybrid desalination systems. The main challenge for the large-scale deployment of nuclear seawater desalination id the lack of infrastructure and resources in the countries affected by water scarcity problems which are however, interested in adoption of nuclear desalination for the sustainable water resources. Socio-economic & environmental aspects and the public perception are also important factors requiring greater information exchange.
Zakaria Atia Mohamed and Abdurrahman Mohy Al-Shehri
Algal flora Chlorophyta, Euglenophyta and Xanthophyta groups were surveyed in six surface water bodies and six groundwater wells between August and December 2003. A total of 29 taxa were recorded during this study, of which 27 belonged to the Chlorophyta, one to the Euglenophyta and one to the Xanthophyta. Most species of Chlorophyta showed diversity in their distribution among all surface water and groundwater sites. However, some species occurred only in surface water sites. On the other hand, one species, Coelastrum microsporum, was recorded only in groundwater sites. The Xanthophycean Tribonema uticulosum was found in both surface water and groundwater sites. The results also showed that some species of belonging to the Chlorophyta and Euglenophyta species were restricted only to a certain site. Compared to the results of previous studies on freshwater algae in Saudi Arabia, thirteen species were new records for Saudi Arabia, of which, 11 belonged to the Chlorophyta, one to the Euglenophyta and one to the Xanthophyta
Ihab Jnad, Jean-Pierre Brunel, Abdullah Droubi
In this study the eddy covariance method results for daily evapotranspiration ET(eddy) in the Palmyra Oasis were compared from the water balance method ET(bal). The eddy covariance measurements were made with a 3D sonic anemometer and Krypton hygrometer. Evapotranspiration estimated by the water balance method was determined using a TDR for soil moisture measurement and a tensiometer for matric potential measurement. A total of 9 pairs of ET(eddy) and ET(bal) daily values were compared. Good agreements were found between the two tested methods with a RMSE of 15.
Abdulrasool Al-Omran, Abdulruzaq Falatah, Abdulaziz Sheta, & Abdulaziz Al-Harbi
The objective of this study was to investigate the effect of irrigation (levels & methods) and type of clay deposits on lettuce yield, water use efficiency WUE and the distributions of soil moisture and salts in the root zone of sandy calcareous soils. A field experiment was conducted at the college experimental station in 2002-2003. It consists of three clay deposits, three rates (0, 1.0, and 2.0%), and four total irrigation applied water levels, 360 mm T1), 520 mm (T2), 635 mm (T3), and 822 mm (T4), using surface and subsurface drip irrigation. Results indicated that yield was significantly increased with the increase of irrigation level whereas WUE significantly decreased with increase of irrigation level. The average yield increased by 9.30% in a high irrigation level compared to a moderate irrigation level and decreased by 14.2% at the more stressed irrigation level. QUE decreased by 49.0% at a moderate irrigation level and decreased by 55% at a high irrigation level. Types of clay deposits did not affect the yield; however, the yield was significantly affected by amendment rates. The differences between surface and subsurface drip on yields and WUE were also significant. Results indicated that the moisture content of the subsurface treated layer increased dramatically, while salts were accumulated at the surface and away from the emitters in subsurface drip irrigation. The advantages of surface drip irrigation were related to the relative decrease in salt accumulation in the root zone area where the plant roots were active and water content was relatively high.
Habib Al-Yosif, Safa Taha and Moiz Bakhiet
There is increasing evidence that inflammatory processes play a central role in the pathogenesis of atherosclerosis. studying the genetic variants of the inflammatory system components in atherosclerosis is very important because it might explain the diverse and variable inflammatory responses among individuals. We herein investigated the possible association between polymorphisms in the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6 and interferon-gamma (IFN-gamma), and the anti-inflammatory cytokines (IL-10 and transforming growth factor-beta1 (TGF-beta1), and correlated them with the severity of cardiovascular complications involving arterial coronary heart disease in 28 Bahraini patients, recruited from Bahrain Defense Forces Hospital (BDFH). Twenty nine asymptomatic subjects were randomly selected from blood donors, and were used as negative controls. For each study object (patients and controls), blood specimen collected and genomic DNA was extracted. Genotyping was performed by SSP method using Cytokine Genotyping Tray kit, followed by electrophoresis. The prevalence of the polymorphisms of all studied cytokines in these patients revealed no significant difference in comparison with the apparently healthy normal control subjects (TNF-alpha p< 0.3735, IL-6 p< 0.2863, IFN-gamma p<0.4222, IL-10 p<0.462, TGF-beta1 p<0.0741). Thus, cytokine genes may not play significant role in coronary heart disease process, as their actual effective protein.
Amhammad A. Al-Razqi, Muftah Al-Rabti, Hussain Taleb, and Suliman Abu Al-Khair
An experiment was conducted to evaluate the growth of Australian atriplex in the semi-arid western parts of Libya, using two water harvesting techniques, namely the contour Ridges and the Negarim Basins Techniques. The criteria used to assess the efficiency of these techniques included measuring the trees' height, circumference, length of the canopy, and maturity. The experiment was conducted in three catchment areas od 10.2, 12.5 and 15.5 m2 for each of the two techniques with three replications. The size of the catchment area was selected based on the crop water requirement, size of the root zone, surface runoff fraction and mean annual rainfall in the region. The ratio of cultivated area to the catchment area was found to be 1:15. Evaluation of the growth of the Australian atriplex was made for two consecutive years. The results of the experiment indicated that the growth of the Australian atriplex in both techniques was superior than those planted outside the water harvesting system (control. However, the overall efficiency of each technique was different depending on technique used and the size of the catchment area, with Contour Ridges technique and the size of the catchment area has the largest effect on the trees growth
Souad Mohamed Al Saqabi
In a survey of intestinal and blood parasites from 350 marsh frogs, Rana ridibunda, were collected from farms in the Eastern Province of Saudi Arabia. Seven species and genera of parasites were found belonging to Protozoa, Nematoda and DIgenea in 1.7% of the population. the parasitic infection was seen more in females than males. The following parasites were recovered and described; from the Protozoa Balantidium duodeni, Nyctotherus cordiformis, Oplina sp. From the Nematoda (Waltonella duboisi), and from the Digenea the genus Pleurogenes was described. In addition, Trypanosoma and Microfilaria were found in the blood of some frogs 2.8% and 1.1% respectively. This is the first report of parasitic infections in Rana ridibunda in the Eastern Province of Saudi Arabia.