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Objectives: The aim of this study was to compare the use of levosimendan versus intra-aortic balloon pump (IABP) in patients with poor left ventricular function undergoing coronary artery bypass grafting (CABG) with ejection fraction less than 35%. Methods: Between February 2016 and March 2019, a prospective randomized study was performed on a group of 279 consecutive patients with left ventricular ejection fraction < 35%, who underwent elective CABG without concomitant procedures. These patients were divided into 2 groups, according to the treatment they received – either levosimendan (Group A) or intra-aortic balloon counterpulsation (Group B). Results: There was no statistically significant difference between the 2 groups, regarding mortality and morbidity. In the IABP group, the mean arterial blood pressure (2 hours post cardiopulmonary bypass) significantly was higher, and the heart rate in postoperative Day 1 significantly was lower. The levosimendan group had a significantly lower ICU stay than the IABP group. Conclusion: We found that starting levosimendan infusion after induction of anesthesia is an acceptable option in comparison to IABP. The use of levosimendan in high-risk cardiac patients is comparable to IABP in improving hemodynamics during and after conventional on-pump CABG and results in a shorter ICU stay.

Problem: Egypt as a developing country, faces a deficit of Current Account, mainly because of the imported products and services' value is more than the exported products and services' value, and the local firms can't compete abroad. The entire research presents a tool that supports the internationalization performance to enable the Egyptian firms to compete abroad. Aim: Presenting the intellectual capital as a tool of developing the internationalization performance to find a solution for the above-mentioned problem. Research design: Both exploratory research and conclusive descriptive researches were conducted. Interviews and online survey were used to get valid data of 41 manufacturing companies working in Egypt for that purpose. Findings: The exploratory research results indicated that the intangible resources have greater effect on internationalization success than the tangible resources. The descriptive research indicated that there are significant relationships between Intellectual Capital (IC), human capital, structural capital, relational capital as independent variables and Internationalization Performance (IP) as a dependent variable at 95% significance level. Research limitations: The entire research is conducted on firms working in a developing country. Results may vary in other developed countries. Besides, the entire research studies IC role in firms' IP, other IC roles and other factors affecting IP may be studied in other researches. Also, the scope of the entire research is industrial and manufacturing firms only.

Nile basin countries are experiencing water scarcity due to rapid growth in population and climate change. This scarcity drew attention to the vast amount of w…

Water is one of the most important inputs for economic development. As the demand increases, so too does the importance of water. This is clearly the case in Egypt, where rainfall is rare and the governmentally enforced quota for withdrawal from the Nile River has not changed since 1959. The water demand has multiplied as a result of population growth, agricultural expansion, as well as industrial development and a rise in the standard of living. In this paper, a vision for the future water status in Egypt is presented. This vision is based on a perception of the current status of the available water resources. The water uses, the water use efficiency, the institutional and legislative frameworks of water management, and the strategies and policies to rationalize water use and to augment water supply are discussed. The local, regional and international governing and controlling factors of water utilization and management in Egypt are also analyzed and discussed. Three future water scenarios for y...

A rainfall-runoff model based on an artificial neural network (ANN) is presented for the Blue Nile catchment. The best geometry of the ANN rainfall-runoff model in terms of number of hidden layers and nodes is identified through a sensitivity analysis. The Blue Nile catchment (about 300 000 km2) in the Nile basin is selected here as a case study. The catchment is classified into seven subcatchments, and the mean areal precipitation over those subcatchments is computed as a main input to the ANN model. The available daily data (1992–99) are divided into two sets for model calibration (1992–96) and for validation (1997–99). The results of the ANN model are compared with one of physical distributed rainfall-runoff models that apply hydraulic and hydrologic fundamental equations in a grid base. The results over the case study area and the comparative analysis with the physically based distributed model show that the ANN technique has great potential in simulating the rainfall-runoff process adequately. Because the available record used in the calibration of the ANN model is too short, the ANN model is biased compared with the distributed model, especially for high flows. Copyright © 2005 John Wiley & Sons, Ltd.

This article addresses the problem of identifying annual operation, maintenance, and replacement (OM&R) expenditures needed to maintain performance of the water delivery system in Egypt. The deliver system, which includes the High Aswan Dam (HAD), large irrigation structures. pump stations, ond thousands of canals and drains, is described. Procedures for estimating these OM&R costs and assessing system benefits in the various use sectors are presented. The article also explains the development and application of a cost allocation model to estimate the share of the various use sectors from the system cost.

The effect of sevoflurane anesthesia with or without induced hypotension on hepatocellular integrity was studied. Forty adult consented patients scheduled for various urological procedures were allocated randomly to either NTG group (nitroglycerin-induced hypotension) or a control group of twenty patients each. Anesthesia was induced and maintained by fentanyl, sevofluranevecuronium in both groups. In NTG group, nitro-glycerin infusion was adjusted to maintain mean arterial pressure (MAP) of 50-65 mm Hg. Specific and sensitive hepatic biomarkers; alpha (alpha) and pi (pi) glutathione S-transferases (GST) and hyaluronic acid (HA), also traditional liver enzymes; aspartate (AST) and alanine (ALT) aminotransferases were measured at: TO (pre-induction), T1, T2, T3 (15, 3060 minutes after MAP stabilization respectively) and T4 (24 hours after anesthesia end). Plasma alpha-GST significantly increased at T3 in control group (p0.05) and in NTG group (p0.01) compared to TO in same group. In NTG group, hyaluronic acid con-centrations was significantly increased at T1, T2 (p0.05) and T3 (p0.01) from T0. Compared to control group, alpha- GSTHA concentrations showed significant increases in NTG group at T3 with p0.05 then returned back to normal range at T4. But, pi-GST, AST and ALT showed no significant changes throughout the study in both groups.

This paper presents a watershed discharge hydrograph simulation model, based on the hydraulically based geomorphologic instantaneous unit hydrograph (IUH), developed by Kirshen and Bras (1983). This IUH was derived as a function of watershed geomorphology and the response of streams to lateral inflows, determined by solving one‐dimensional linearized equations of motion. The effective rainfall is calculated here to be equal to the gross rainfall minus the infiltration losses, presented with Philip's expression coupled with an empirical equation for soil moisture computation. Consideration is given to the role of mountainous terrain in runoff generation. For mountainous watersheds, the mountain runoff is regarded as a water depth on the alluvial channels. The effective rainfall depth is calculated to be equal to this water depth plus the rainfall depth minus the infiltration losses. The simulation model is verified through applications for three gauged watersheds in Saudi Arabia. A comparison is made betwe...

The role of agricultural expansion investment in improving the income redistribution conditions in society has been of considerable concern to planners. In this paper an approach based on distributing the newly developed land to a poorer sector (landless farmers) in society to gain agricultural revenues and improve their income is investigated. A mathematical optimization model is built to determine the distribution of land and a pricing policy established for the new areas in such a way that (1) a specified (by the government) income increase to the farmers can be achieved, (2) a predetermined level of recovery of the expansion cost can be insured, (3) high agricultural efficiency in the new land can be maintained, and (4) redistribution benefits can be maximized. In a case study application of the model, no conflict is found between the economic efficiency and income redistribution cirtieria in agricultural expansion investment within the planning framework presented in the companion paper (Allam and Marks, this issue). For a specified cost recovery condition it is found that the least cost planning alternatives give the opportunity to the largest number of landless farmers to own the new land and receive a specified income increase from the agricultural revenues, but a conflict between government return from the investment and redistribution objectives is found. This conflict is addressed and the trade-off between the two objectives is illustrated.

An approach for estimating irrigation water cost is presented and applied to Upper Egypt. Two cost models are used. The first model is to estimate the cost of irrigation water if controlled with a multi-purpose structure. The model is used in estimating the irrigation cost at the High Aswan Dam. The second model is to allocate the cost of irrigation structures and the cost of irrigation at the multi-purpose structures among the served areas. The two models are applied to estimate the cost of irrigation water at the different regions of Upper Egypt.

Agricultural expansion planning in developing countries where there is extensive government involvement in the planning process can be defined in a two-level hierarchy. At the first level, the role of the agricultural expansion investment in achieving the strategic goals of the sector is to be determined. At the second level, analysis of the agricultural expansion is to be carried out in such a way that the strategic decisions from the first level can be implemented. The focus of this paper is on the analysis of investment scheduling, the major issue of the second level. A mathematical optimization model is built to aid in analyzing the scheduling problems of land development, crop selection, drainage water reuse, and capacity expansion of the irrigation and drainage networks. A minimum cost criterion is used, where costs of land development, farming, irrigation and drainage infrastructures, maintenance and operations, and pump stations are considered. The model has a nonlinear objective function to account for economies of scale and linear and nonlinear constraints. A fixed charge approximation is used for the nonconvex cost functions, and a mixed integer programming algorithm along with an enumeration procedure is used for solving the model. The solution procedure guarantees global optimality for the approximated problem. A hypothetical expansion of 70,000 acres (28,350 ha) based on data from the Nile Delta in Egypt is used as a case study to illustrate the procedure under different conditions of irrigation water quality.

The conflict between performance measured in terms of economic and income redistribution objectives, resilience and reliability of irrigated agricultural expansions in developing countries is investigated via a planning framework consisting of three sequential optimization models. The first model determines the most economic planning alternatives. The second model examines, in terms of an income redistribution criterion, the social attractiveness of each plan. The third model determines resilience and operating rules of the various alternatives. The planning framework is appled for a hypothetical agricultural expansion on the order of 30 000 hectares based on data from the Nile Delta in Egypt. The trade-off between system performance, reliability and resilience is derived.

A two-dimensional finite-element model has been adapted to simulate the aquifer underlying the Nile Valley of Egypt. Calibration of the model led to the determination of the interaction between the ground water and the Nile surface water. Results obtained from the model were compared with those obtained from simple hydrologic budget analyses and were found to be quite comparable. The model is, thus, considered to adequately represent the ground-water system of the Nile Valley and may be used to forecast the effects of managing the integrated ground-water/surface-water system.

Water demand in the Kingdom of Saudi Arabia has increased from 1750 million cubic meters (Mm3) in 1975to more than 9,600 Mm3 in 1985, a five-fold increase in ten years. At the same time increase on the supply side through water recycling and seawater desalination has been from around 18 Mm3 to 605 Mm3 during the same period. The development of these additional water supplies have been, however, far short of the increase in water demand, with groundwater making up the difference. This paper examines the above problem from the viewpoint of supply-demand balance. First, the paper assesses the surface and groundwater resources of the Kingdom, and the present as well as the future conditions of sea water desalination and water cycling. The water demands of the various use sectors are given followed by projections of future water demands. The third phase compares the water supply-demand situation under present and future conditions. From this comparison it was evident that unless there is a change in the current water use practices, groundwater, the major water resource of the Kingdom, will be mined in few decades and the extent that its usefulness may be severely diminished as a resource. When this develops, a severe water crisis will occur. The crisis can be reduced in severity, or averted, by taking the needed steps to bring into balance the annual water use with annual water supply.

A multicriteria optimization model is built to determine performance as well as operating rules of an agricultural system under future uncertainties inherent in the planning parameters. Performance of the agricultural systems is measured in terms of the economic efficiency and income redistribution criteria. The operating decisions are determined in such a way that the reduction in performance due to unpleasant surprises in the planning parameters can be minimized. The multicriteria model is used in deriving the relationship between the performance of a case study and the unpleasant changes in the planning parameters. A resiliency index in terms of the gradients of these functional relationships in a probabilistic framework is provided. Based on this resiliency index, a definition of resilient system design is reached.

Background Many studies have shown important changes in lung function tests after coronary artery surgeries. It is controversial if off-pump surgery can give a better and shorter recovery than the on-pump. The aim of this work was to study immediate early pulmonary dysfunction in ischemic heart disease patients undergoing off-pump versus on-pump coronary artery bypass grafting (CABG) in order to evaluate pulmonary dysfunction caused by cardio-pulmonary bypass (CPB) in patients undergoing on-pump CABG. Patients and method A prospective randomized study was carried out on 40 patients submitted to coronary artery surgery at Kasr El-Aini University Hospital, Cairo, Egypt. They were randomly divided into two groups; group A: 20 patients undergoing CABG using heart-lung machine (on-pump), and group B: 20 patients undergoing off-pump CABG. All patients had: spirometric evaluation, 6 min walk test pre-operatively and at the post-operative fifth day. Measurement of arterial blood gases (ABGs) and calculation of P/F ratio was recorded pre-operative, post-induction and post CABG. Post-operative intensive care unit (ICU) events were also assessed. Results Post-operative spirometric data and 6 min walk distance decreased in both groups, when compared to pre-operative values, with significant differences between the two groups. No significant reduction in arterial oxygen pressure (PaO 2 ), carbon dioxide pressure (PaCO 2 ) and P/F Ratio occurred post-operatively. Conclusion Pulmonary functions deteriorate significantly after coronary artery revascularization with and without CPB, but to a significant greater reduction among those on-pump than among those off-pump surgeries.

Recently hydrologic models based on the geomorphologic theory for the prediction of discharge hydrographs of ungauged watersheds have been developed. The paper presents a review on these models and on their mathematical development. One of these models, which accounts for the infiltration in watersheds, is applied for Elmaghara basin in the northern part of Sinai. A geomorphoclimatic model for the prediction of surface runoff volumes is also presented and applied for the same basin. The model has a simple structure and is applicable for large scale basins. It is designed in such a way that a physically based expression for iniltration can be considered. The effects of infiltration on the surface runoff of the basin are illustrated.