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OALib Journal期刊

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匹配条件: “ Mohamed A. Ragheb” ,找到相关结果约468151条。
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The Role of Branding on Educational Performance in the Egyptian Private Universities  [PDF]
Amel Rashwan, Ayman Shawky, Mohamed A. Ragheb, Alaa A. Bary
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104882
Abstract:
This paper aims to investigate the role of branding in achieving a good perfor-mance level for Egyptian universities. It explains the value of impact of each dimension of the Branding, which are: Design, Communication and Feedback, on Performance, represented in Alumni, Employment and Learning Efficiency. Regression analysis and SEM were conducted and results show that none of the Branding dimensions significantly affects Learning Efficiency. On the other hand, all Branding dimensions are significantly affecting Alumni. It could be concluded that there should be some enhancements regarding the programs provided for post graduates to be able to achieve the required level of learning efficiency.
Factors That Influence Entrepreneurial Intention within University Students in Egypt  [PDF]
Assem Sharaf, Alaa El-Gharbawy, Mohamed A. Ragheb
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104881
Abstract:
The current research aims to propose a framework of the effects of behav-ioral factors of theory of planned behavior and psychological traits factors on students’ entrepreneurial intention, measuring the size of effect, the circumstances under which the effect is clearly observed and studying the weighted effect of each of the behavior and traits elements. A questionnaire was adopted from previous studies and directed to students in the Egyptian universities. A total number of 430 respondents were considered and data were analyzed using AMOS through conducting SEM models for examining the effect of behavior and traits. Results showed that there is a significant effect of attitude toward behavior on students’ entrepreneurial intention, while there is an insignificant effect of traits.
Biosafety of Recombinant and Wild Type Nucleopolyhedroviruses as Bioinsecticides
Mohamed-Bassem Ashour,Didair A. Ragheb,El-Sayed A. El-Sheikh,El-Adarosy A. Gomaa,Shizuo G. Kamita,Bruce D. Hammock
International Journal of Environmental Research and Public Health , 2007, DOI: 10.3390/ijerph2007040005
Abstract: The entomopathogenic Autographa californica (Speyer) nucleopolyhedrovirus (AcMNPV) has been genetically modified to increase its speed of kill. The potential adverse effects of a recombinant AcMNPV (AcAaIT) as well as wild type AcMNPV and wild type Spodoptera littoralis NPV (SlNPV) were studied. Cotton plants were treated with these viruses at concentrations that were adjusted to resemble the recommended field application rate (4 x 1012 PIBs/feddan, feddan = 4,200 m2) and 3rd instar larvae of S. littoralis were allowed to feed on the contaminated plants. SDS-PAGE, ELISA, and DNA analyses were used to confirm that larvae that fed on these plants were virus-infected. Polyhedra that were purified from the infected larvae were subjected to structural protein analysis. A 32 KDa protein was found in polyhedra that were isolated from all of the viruses. Subtle differences were found in the size and abundance of ODV proteins. Antisera against polyhedral proteins isolated from AcAaIT polyhedra were raised in rabbits. The terminal bleeds from rabbits were screened against four coating antigens (i.e., polyhedral proteins from AcAaIT, AcAaIT from field-infected larvae (AcAaIT-field), AcMNPV, and SlNPV) using a two-dimensional titration method with the coated antigen format. Competitive inhibition experiments were conducted in parallel to optimize antibody and coating antigen concentrations for ELISA. The IC50 values for each combination ranged from 1.42 to 163 μg/ml. AcAaIT-derived polyhedrin gave the lowest IC50 value, followed by those of SlNPV, AcAaIT-field, and AcMNPV. The optimized ELISA system showed low cross reactivity for AcMNPV (0.87%), AcAaIT-field (1.2%), and SlNPV (4.0%). Genomic DNAs isolated from AcAaIT that were passaged in larvae of S. littoralis that were reared in the laboratory or field did not show any detectable differences. Albino rats (male and female) that were treated with AcAaIT, AcMNPV or SlNPV (either orally or by intraperitoneal injection at doses of 1 x 108 or 1 x 107 PIBs/rat, respectively) appeared to be healthy and showed increased body weight at 21 days posttreatment. The effect of virus administration on hematological, serum biochemical, and histopathological parameters were determined. Slight to moderate differences were observed in most of the hematological parameters. Specifically, serum proteins were decreased markedly in female rats treated orally with SlNPV, and in male rats injected with AcAaIT. SDS-PAGE analysis also showed some changes in serum protein profiles. No marked changes in acetylcholine esterase (AChE) activity were found. Changes in serum glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), bilirubin, creatinin, and urea were also observed. Immunohistochemical observation of tissues from stomach, intestine, liver, kidney, brain, spleen, and lung also showed slight changes. Fish (Tilapia nilotica) were also exposed to AcAaIT, AcMNPV or SlNPV by incorporating each of the viruses into diet (1 x 109 PIBs/group). No mortality was found in treated or untreated fish during the experimental period (28 days). Macrophage phagocytic activity of fish head kidney cells increased with time, reaching maximum values at 180 min for both treated and control fish.
Composition of Coccinelid communities in sugar beet fields in Vojvodina
Thalji Ragheb A.
Zbornik Matice Srpske za Prirodne Nauke , 2006, DOI: 10.2298/zmspn0610267t
Abstract: This paper presents a synthesis of the results obtained during a long- -term investigations conducted on the distribution of aphidophagous coccinellid species and their quantitative and qualitative structure in sugar beet fields in Vojvodina. Composition of coccinellid communities and the annual changes in abundance of species are influenced by many variable environmental factors, but also by the prey availability during the season. Chemical treatments against flea beetles in May or/and against noctuid larvae in late July and the type of the adjacent crops may also affect the quantitative composition of adults coccinellid on sugar beet fields. During the season adults coccinellid are more abundant than larvae. The qualitative structure of coccinellid communities in sugar beet fields is not different than those from other field crops. These communities consist mainly of Coccinella septempunctata L.; Semiadalia undecimnotata Schn.; Propylaea quatuordecimpunctata L.; Hippodamia (Adonia) variegata Goeze and Hippodamia tredecimpunctata L. Other species are present in a small fractions.
Plane Wave Scattered by N Dielectric Coated Conducting Strips Using Asymptotic Approximate Solution
Hassan A. Ragheb;Essam E. Hassan
PIER B , 2010,
Abstract: The paper aims at solving the problem of plane electromagnetic waves scattered by N dielectric coated conducting strips. The method used is based on an asymptotic technique introduced by Karp and Russek for solving scattering by wide slit. The technique assumes the total scattered field from each coated strip as the sum of the scattered fields from the individual element due to a plane incident wave plus scattered fields from factious line sources of unknown intensity located at the center of every element. The line sources account for the multiple scattering effect. By enforcing the boundary conditions, the intensity of the line sources can be calculated. Numerical examples are introduced for comparison with data published in the literature.
Design of an Efficient IIR Filter for SIGMA – DELTA Modulation
Essam E. Hassan,Hassan A. Ragheb
Elektrika : Journal of Electrical Engineering , 2008,
Abstract: The problem of designing an IIR digital filter to minimize the output filtered quantization noise power in sigma-delta modulation is attempted. Employing the bilinear transformation, the filter is designed first in the analog frequency domain. Its transfer function is assumed to be a rational function with its numerator being an even power polynomial with unknown coefficients and its denominator is chosen as the linear phase polynomial which is strictly Hurwitz. The filter coefficients are optimized with respect to a comparable SincN filter. Finally, the digital representation of the filter is extracted from its analog counterpart. It is shown that the design achieves a considerable saving in the filter size while keeping a comparable characteristic to the much larger FIR comb filter.
Urinary Neutrophil Gelatinase Associated Lipocalin as a Marker of Tubular Damage in Type 2 Diabetic Patients with and without Albuminuria  [PDF]
Abeer A. Al-Refai, Safaa I. Tayel, Ahmed Ragheb, Ashraf G. Dala, Ahmed Zahran
Open Journal of Nephrology (OJNeph) , 2014, DOI: 10.4236/ojneph.2014.41006
Abstract:

Background: Neuttrophil gelatinase associated lipocalin (NGAL) was shown to be a good marker for predicting acute kidney injury (AKI). Some recent reports demonstrated that NGAL may be an early biomarker for kidney affection in diabetic patients. The aim of this work is to investigate urinary NGAL (UNGAL) in type 2 diabetic patients with and without albuminuria. Methods: This study included 46 type 2 diabetic patients and 15 healthy age and sex matched individuals as the control group. Diabetic patients were divided into three groups according to urinary albumin excretion (UAE), normoalbuminuria, microalbuminuria and macroalbuminuria. UNGAL was measured in all populations and corrected to urinary creatinine to account for day to day variation in urine volume and transformed log. Comparison between 4 groups (control, normoalbuminuria, microalbuminuria and macroalbuminuria) was done. Results: Log UNGAL/Creatinine ratio showed significant difference when comparing control group (0.70 ± 0.58) versus normoalbuminuria (1.71 ± 1.06), microalbuminuria (1.57 ± 0.72) and macroalbuminuria (1.92 ± 0.63), however,

Evidence to Support a Putative Role for Insulin Resistance in Chronic Kidney Disease
W Shehab-Eldin, A Ragheb, S Gazarin, A Shoker
Arab Journal of Nephrology and Transplantation , 2009,
Abstract: Introduction: The primary cause of morbidity and mortality in the renal patient is a cardiovascular event. Insulin resistance (IR) contributes to this event by increasing cardiovascular disease (CVD) and accelerating rates of decline in kidney function. Here we review the historical background of IR in patients with chronic kidney disease (CKD) and present evidence for a role of IR in accelerating cardiovascular and renal diseases. Review: The high prevalence of IR in CKD patients is well documented. It is suggested that increased IR in the renal patient is caused by uremia as well as by other known factors in the general population. Patients with CKD have an alarmingly high risk for cardiovascular morbidity and mortality. There is overwhelming evidence to support a role for IR in increased CVD morbidity and mortality in the general population, which is likely to extend to CKD patients. Some of the traditional treatment measures for IR, such as metformin, may not be applicable to the renal patient. Other options include weight reduction, exercise, treatment of anemia to improve exercise tolerance, treatment of vitamin D deficiency, thiazolidinediones, and dialysis. IR is estimated by studying the relationship between blood glucose and the concomitant insulin level. Such measurement may help identify patients at increased risk for future cardiovascular events and guide treatment measures. Conclusion: Sufficient evidence supports the increased prevalence of IR in kidney patients. Treating IR may retard the progression of CKD and decrease the incidence of cardiovascular events in this high risk population.
Transformational Leadership as a Critical Success Factor for Enterprise Resource Planning System Implementation  [PDF]
Wael A. Agha, Mohmaed A. Ragheb, Ayman Y. Shawky
Open Access Library Journal (OALib Journal) , 2019, DOI: 10.4236/oalib.1105243
Abstract:
The successful implementation of an enterprise resource planning (ERP) system has been described as a challenging strategic initiative for many organizations in varied business settings and different organizational cul-tures. During the past two decades, there has been massive investment in adopting ERP system, in addition to a substantial increase in focusing on the importance of users’ acceptance of utilizing such technological technique. Despite the many advantages of successful installing of ERP system demonstrated in literature but still the failure rate of ERP projects is re-markably high. Leaders of ERP implementation projects have the challenge of displaying effective leadership skills and traits to justify strategic and operational decisions taken during implementation of ERP system. To provide better understanding of what may positively influence a successful implementation of ERP system, this research study is an attempt to inves-tigate whether leadership style especially transformational leadership has a significant impact on successful implementation of ERP systems. The theory of transformational and transactional leadership was the foundations for the researched leadership style in this study. A quantitative, non-experimental correlational empirical research strategy examined the degree of significance of the direct relationship between the independent variable of transformational leadership style and the dependent variable, perceived as ERP success. Projects’ leaders, executives, information technology, business managers, and end users who involved in adopting and using ERP system within their Egyptian organizations representing various business settings, were the targeted population of this research. Structural Equation Modeling (SEM) was conducted to test the research hypotheses and analyze the findings and results. The results of the study supported the existence of a significant relationship between transformational leadership style and successful implementation of ERP system.
A Particle Swarm Optimization Algorithm for a 2-D Irregular Strip Packing Problem  [PDF]
Mohamed A. Shalaby, Mohamed Kashkoush
American Journal of Operations Research (AJOR) , 2013, DOI: 10.4236/ajor.2013.32024
Abstract:

Two-Dimensional Irregular Strip Packing Problem is a classical cutting/packing problem. The problem is to assign, a set of 2-D irregular-shaped items to a rectangular sheet. The width of the sheet is fixed, while its length is extendable and has to be minimized. A sequence-based approach is developed and tested. The approach involves two phases; optimization phase and placement phase. The optimization phase searches for the packing sequence that would lead to an optimal (or best) solution when translated to an actual pattern through the placement phase. A Particle Swarm Optimization algorithm is applied in this optimization phase. Regarding the placement phase, a combined algorithm based on traditional placement methods is developed. Competitive results are obtained, where the best solutions are found to be better than, or at least equal to, the best known solutions for 10 out of 31 benchmark data sets. A Statistical Design of Experiments and a random generator of test problems are also used to characterize the performance of the entire algorithm.

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