Privatization of Sanitation and Desalination Projects in Palestine

Abstract

The present problems that are related to water and sanitation in Palestine are many and varied, and the disparity between water supply and demand is growing with time due to the rapid population growth and aridity. Desalination has the potential to supply unlimited quantities of high-quality freshwater to Palestinian Communities. On the other hand, the situation of the sewerage system in the cities is extremely critical, and there are no sewerage systems in the rural areas. There is an urgent need for substantial improvements and extensions to the sewerage systems and treatment plants. The available funds for the Palestinian Water Authority (PWA) and other municipalities to implement wastewater and desalination projects are limited. As a result, it is important to fully explore the use of public-private partnerships that utilize sector resources to finance such projects. The objective of this study is to understand incentives for privatization of water supply and sanitation services, with more emphasis on the households' Affordability and Willingness-to-Pay (AWTP) for improved water and sanitation services. The results show that people in Palestine bear the burden of high water supply and sanitation costs. Privatization of the water and sanitation sector will guarantee sustainable development of these sectors under limited financial resources and dependency on external funds.     

A Financial,Environmental and Social Evaluation of Domestic Water Management Options in the West Bank,Palestine

Water is one of the most valuable natural resources in the West Bank, Palestine. Due to its limited availability, it is a resource that needs particular protection. Although agriculture consumes most of the water (70%) in the West Bank, the domestic water supply is strategically not less important. It is the aim of this study to evaluate domestic water management options suitable for Palestinian conditions that contribute to achieving water sufficiency in the domestic water use in the house of tomorrow. A number of options were evaluated economically, environmentally and socially using the concept of life cycle impact assessment (LCIA). Results of the study showed that by introducing a combination of domestic water management options, a substantial decrease in the water consumption of more than 50% can be achieved, thereby reducing the pressure on the scarce water resources. The annual environmental impact of the in-house water use can be reduced in the range of 8%, when using low-flow shower head to 38% when using rainwater harvesting systems. Some of the options (faucet aerators, low-flow shower heads and dual flush toilets) were found to be financially attractive with a pay back period of less than their expected lives, others (rainwater harvesting, graywater reuse and dry toilets) were found to be financially unattractive because of the high investment. In the social context, it was found that introducing such options can improve the quality of life of those not having enough water. There is already a popular willingness to take part in water conservation in the domestic sector in the West Bank. The strongest driving force for using water conservation measures is the awareness that water is a scarce resource. It was concluded that, theoretically, the house of tomorrow can be largely independent in terms of water and sanitation. Education and awareness campaigns in the context of water management with a focus on non-traditional options are key to achieve such a house.     

Highly Efficient Fluorescent Interstrand Photo‐crosslinking of DNA Duplexes Labeled with 5‐Fluoro‐4‐thio‐2′‐O‐methyluridine

The formation of a fluorescent photoadduct between 5‐fluoro‐4‐thiouridine ( ^FS U ), in the sequence context 5′‐A ^FS U A‐3′ and incorporated into a synthetic oligonucleotide either at its 3′‐ or 5′‐end, and one of the thymines of the TAT motif in a complementary target DNA strand led to photo‐crosslinking of the two strands for several oligonucleotide constructs. Enzymatic digestion, MS, UV, and fluorescence spectral analyses of the interstrand crosslinked oligonucleotides revealed the identity of the thymidine that participates in the photo‐crosslinking reaction as well as the diastereomeric structures of the crosslinks. The proposed pathways of interstrand photo‐crosslinking are supported by experiments with isotopically labeled oligonucleotide constructs and visualized by means of molecular dynamics simulations.     

Computational micromechanical analysis of the representative volume element of bituminous composite materials

Micromechanical computational modeling is used in this study to determine the smallest domain, or Representative Volume Element (RVE), that can be used to characterize the effective properties of composite materials such as Asphalt Concrete (AC). Computational Finite Element (FE) micromechanical modeling was coupled with digital image analysis of surface scans of AC specimens. Three mixtures with varying Nominal Maximum Aggregate Size (NMAS) of 4.75 mm, 12.5 mm, and 25 mm, were prepared for digital image analysis and computational micromechanical modeling. The effects of window size and phase modulus mismatch on the apparent viscoelastic response of the composite were numerically examined. A good agreement was observed in the RVE size predictions based on micromechanical computational modeling and image analysis. Micromechanical results indicated that a degradation in the matrix stiffness increases the corresponding RVE size. Statistical homogeneity was observed for window sizes equal to two to three times the NMAS. A model was presented for relating the degree of statistical homogeneity associated with each window size for materials with varying inclusion dimensions.     

Low doses of eicosapentaenoic acid, docosahexaenoic acid, and hypolipidemic eicosapentaenoic acid derivatives have no effect on lipid peroxidation in plasma

It was of interest to investigate the influence of both high doses of eicosapentaenoic acid (EPA) and low doses of 2-or 3-methylated EPA on the antioxidant status, as they all cause hypolipidemia, but the dose required is quite different. We fed low doses (250 mg/d/kg body wt) of different EPA derivatives or high doses (1500 mg/d/kg body wt) of EPA and DHA to rats for 5 and 7 d, respectively. The most potent hypolipidemic EPA derivative, 2,2-dimethyl-EPA, did not change the malondialdehyde content in liver or plasma. Plasma vitamin E decreased only after supplementation of those EPA derivatives that caused the greatest increase in the fatty acyl-CoA oxidase activity. Fatty acyl-CoA oxidase activity increased after administration of both EPA and DHA at high doses. High doses of EPA and DHA decreased plasma vitamin E content, whereas only DHA elevated lipid peroxidation. In liver, however, both EPA and DHA increased lipid peroxidation, but the hepatic level of vitamin E was unchanged. The glutathione-requiring enzymes and the glutathione level were unaffected, and no significant changes in the activities of xanthine oxidase and superoxide dismutase were observed in either low-or high-dose experiments. In conclusion, increased peroxisomal β-oxidation in combination with high amounts of polyunsaturated fatty acids caused elevated lipid peroxidation. At low doses of polyunsaturated fatty acids, lipid peroxidation was unchanged, in spite of increased peroxisomal β-oxidation, indicating that polyunsaturation is the most important factor for lipid peroxidation.     

Possible evidence for the existence of a hairy layer at the surface of polymer latex particles †

In this work, an attempt is made to verify the existence of a hairy layer at the surface of polymer latex particles, and determine its thickness under different conditions. Two systems have been studied. In one system, sodium dodecyl sulphate (SDS) and sodium dodecanoate (laurate-SL) were used, separately, as emulsifiers in ab initio (unseeded) emulsion polymerization of styrene carried out at different ionic strengths. At low levels of electrolyte (NaCl in the range 0·00– 0·10M), the hydrodynamic radius (d_H) was found to decrease gradually, reaching a minimum value at 0·10M, about 7–9nm smaller than the original value in the absence of electrolyte. At electrolyte levels higher than 0·10M, d_H increased monotonically. In the first observation, the results are interpreted in terms of a hairy layer model, which suggests that the thickness of this layer is reduced by the presence of an electrolyte because of charge shielding, while the increased d_H at high ionic strength is interpreted in terms of coalescence between latex particles. The extent of the effect depends mainly on the concentration of emulsifier. In the second system, the effect on a seeded emulsion polymerization of styrene was investigated. In this system, a seed latex containing about 10% solids was prepared with SDS as emulsifier. The monomer was then further polymerized at different ionic strengths with no more added emulsifier. The effect on d_H was very similar to that of the first system. However, in a previous investigation on this system (Polym. Int., 40 (1996) 307) the rate of seeded polymerization was not affected in the electrolyte range 0·0–0·1M, while it was found to increase with increasing electrolyte level in the range 0·10–0·20M. Post-addition of electrolyte (0·0–0·1M) to the seed latex results in a 4–6nm size contraction due to an increase in the hydrophobicity of the surface, leading to a backward extension away from the aqueous phase. © 1998 Society of Chemical Industry     

Dietary fat alters biliary lipid secretion in the hamster

Dietary fat has been found to alter the incidence of cholesterol gallstones in hamsters: butterfat intensifies while safflower oil reduces lithiasis. We now report how dietary fat affects bile flow and biliary lipid secretion in this model. Male hamsters were fed one of three experimental diets: a control diet (containing 0.3% cholesterol); control diet +4.0% butterfat; or control diet +4.0% safflower oil. After three weeks, bile samples were collected via an external biliary fistula. The endogenous bile acid pool was depleted for 120 min followed by increasing rates of taurocholate infusion for 160 min. Basal secretion of biliary lipids was measured during the bile acid depletion period. Basal bile flow and bile acid output were not significantly different in the three groups. Dietary butterfat increased basal cholesterol output compared to the control diet (0.037 vs. 0.025 μmol/min·kg, respectively); safflower oil did not change cholesterol output (0.027 μmol/min·kg). Hamsters fed butterfat or safflower oil secreted more phospholipid (0.171 and 0.178 μmol/min·kg, respectively) than controls (0.131 μmol/min·kg). The cholesterol/phospholipid output ratio of the butterfat group was higher than the safflower oil group (0.220 vs. 0.153, respectively). Effects of dietary fat on several relationships between bile flow and biliary lipid secretion were analyzed by linear regression using the data for the entire bile collection period (bile acid depletion and taurocholate infusion). Butterfat and safflower oil did not change either bile acid dependent or bile acid independent bile flow. Hamsters fed butterfat had a higher linkage coefficient (slope) of cholesterol vs. bile acid output than the safflower oil group (0.023 vs. 0.009, respectively). The linkage coefficient of phospholipid vs. bile acid output of the butterfat group was higher than the controls (0.278 vs. 0.185, respectively). In summary, butterfat induced a high cholesterol and phospholipid secretion with a high cholesterol/phospholipid output ratio; safflower oil induced a high phospholipid secretion with a low cholesterol/phospholipid output ratio. Butterfat and safflower oil have different effects on biliary lipid secretion. These differences in biliary lipid secretion may explain, in part, how butterfat and safflower oil differ in affecting gallstone formation in hamsters.     

Schedulable garbage collection in CLI virtual execution system

Virtual software execution environment, known as Virtual Machine (VM), has been gaining popularity through Java Virtual Machine (JVM) and Common Language Infrastructure (CLI). Given their advantages in portability, productivity, and safety, etc., applying VM to real-time embedded systems can leverage production cost, fast time-to-market, and software integrity. However, this approach can only become practical once the VM operations and application tasks are made schedulable jointly. In this paper, we present a schedulable garbage collection algorithm applicable on real-time applications in CLI virtual machine environment. To facilitate the scheduling of real-time applications and garbage collection operations, we make the pause time due to garbage collection controllable, and the invocation of garbage collection predictable. To demonstrate the approach, a prototype for a schedulable garbage collection has been implemented in CLI execution environment. The garbage collection is carried out by a concurrent thread while meeting a targeted pause time and satisfying the memory requests of applications. A cost model of garbage collection is established based on measured WCET such that the execution time and overhead of garbage collection operations can be predicted. Finally, we illustrate a joint scheduling algorithm to meet the time and memory constraints of real-time systems.     

Comparison of measurements of the outer scale of turbulence by three different techniques

We have made simultaneous and nearly simultaneous measurements of L0, the outer scale of turbulence, at the Palomar Observatory by using three techniques: angle-of-arrival covariance measurements with the Generalized Seeing Monitor (GSM), differential-image-motion measurements with the adaptive-optics system on the Hale 5-m telescope, and fringe speed measurements with the Palomar Testbed Interferometer (PTI). The three techniques give consistent results, an outer scale of approximately 10-20 m, despite the fact that the spatial scales of the three instruments vary from 1 m for the GSM to 100 m for the PTI.