Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

9 ( 1 )

2019 ( 565 )

2018 ( 958 )

2017 ( 868 )

Custom range...

Search Results: 1 - 10 of 468699 matches for " Mohamed A. Korany "
All listed articles are free for downloading (OA Articles)
Page 1 /468699
Display every page Item
Catalyst Free Synthesis of Pyridine-2,6-bis(2-bromo-propane-1,3-dione) and Pyrdine-2,6-bis(N-arylthiazoline-2-thiones)  [PDF]
Korany A. Ali, Mohamed A. Elsayed, Eman Ali Ragab
Green and Sustainable Chemistry (GSC) , 2015, DOI: 10.4236/gsc.2015.51006
Abstract: We have described herein a catalyst-free preparation method of pyridine-2,6-bis(N-alkylthiazoline-2-thiones) (4a-i) by the reaction of primary amines, CS2, and pyridine-2,6-bis(2-bromo-1,3- dicarbonyl) derivatives (2a-c) in water. Also, we have described a catalyst free, green chemistry protocols to monobromination of pyridine-2,6-bis(2-bromo-1,3-dicarbonyl) derivatives with high yield, using NBS as a brominating agent, that led to eco-friendly isolation and purification proce-dures. Furthermore, we have studied the reactivity of pyridine-2,6-bis(2-bromo-1-methyl-pro- pane-1,3-dione) (2a) towards thiourea to afford 2,6-bis(5-benzoyl-2-aminothiazol-4-yl)pyridine (9).
APO-1/FAS Promoter (-670A/G) Polymorphisms and Risk of Lupus Nephritis in SLE Egyptian Female Patients  [PDF]
Eman A. E. Badr, Ghada E. Hamoda, Heba A. Esaily, Mohamed A. Korany
Open Journal of Genetics (OJGen) , 2015, DOI: 10.4236/ojgen.2015.52007
Abstract: Background: Self-immunization in systemic lupus is driven by defective in apoptosis. Fas, is an apoptosis-promoting cell surface receptor. The present study evaluate the possible association between APO-1/FAS Promoter (-670A/G) Polymorphism and sFAS level with susceptibility to lupus nephritis in SLE patients. Design and Methods: This study was performed on 88 female patients with SLE (mean age, 39.82 ± 10.16 years). 82 patients with lupus nephritis (mean age, 42.50 ± 6.65 years). 150 age and sex-matched person served as controls. All participants were genotyped for the APO-1/FAS Promoter (-670A/G) Polymorphism, manifestations and serum sFAS were correlated with the genotypes. Results: Serum sFAS was significantly higher in patients with -670 AA genotype compared to others. (-670A/G) AA genotype frequencies were significantly higher in the lupus nephritis and SLE patients groups compared with the controls and were associated with increased risk for lupus nephritis and SLE development (odds ratio, 4.08 and 1.91 respectively). Conclusions: The APO-1/FAS Promoter (-670A/G) A allele can be used as a genetic marker for lupus nephritis susceptibility in SLE and was associated with high sFAS level.
Ontology-based Social Recommender System
Abeer Mohamed El-korany,Salma Mokhtar Khatab
IAES International Journal of Artificial Intelligence (IJ-AI) , 2012, DOI: 10.11591/ij-ai.v1i3.778
Abstract: Knowledge sharing is vital in collaborative work environments. People working in the same environment aid better communication due to sharing information and resources within a contextual knowledge structure constructed based on their scope. Social networks play important role in our daily live as it enables people to communicate, and share information. The main idea of social network is to represent a group of users joined by some kind of voluntary relation without considering any preference. This paper proposes a social recommender system that follows user’s preferences to provide recommendation based on the similarity among users participating in the social network. Ontology is used to define and estimate similarity between users and accordingly being able to connect different stakeholders working in the community field such as social associations and volunteers. This approach is based on integration of major characteristics of content-based and collaborative filtering techniques. Ontology plays a central role in this system since it is used to store and maintain the dynamic profiles of the users which is essential for interaction and connection of appropriate knowledge flow and transaction.
The global and UV-B radiation over Egypt
Atmósfera , 2007,
Abstract: this work studies the relation between uv-b radiation and global radiation over egypt. the relationships between the global solar radiation and uv-b radiation at four stations in egypt have been studied, and linear empirical formulas for estimating uv-b from global radiation at these stations has been deduced. the deduced equations were applied to calculate the uv-b radiation for other stations where measurements were unavailable, using records of global radiation at these stations. because of the periodicity of variations in solar radiation, global and uv-b radiation, the non-dimensional values are expanded in fourier series. fourier coefficients were determined by using measured global solar radiation data of the selected stations. these coefficients were used to calculate uv-b radiation based on global solar radiation for the same stations. a comparison between observed and calculated uv-b radiation arising from the two methods of estimation is presented. the comparison showed a good agreement between the observed and estimated uv-b radiation. the application of linear regression method to calculate solar radiation for other stations where uv-b radiation measurements were unavailable was better than fourier coefficients method.
An Interaction Study Between Pifas Handset Antenna and a Human Hand-Head in Personal Communications
Ahmed M. Montaser;Korany Ragab Mahmoud;Hamdy A. Elmikati
PIER B , 2012, DOI: 10.2528/PIERB11091514
Abstract: In this paper, the interaction of a planar inverted-F antennas array, mounted on a mobile handset, with a human hand-head phantom is investigated in the 1.9 GHz band. The hybrid approach involving the particle swarm optimization (PSO) and Nelder-Mead (NM) algorithm is considered to optimize the complex excitations of the adaptive array elements in a mutual coupling environment for different beamforming synthesis. Firstly, the effect of the human hand-head on the handset radiation characteristics is studied. Then, the spatial-peak specific absorption rate (SAR) values of 2- and 4-element PIFA arrays for mobile handset in the vicinity of a human hand-head are evaluated numerically for different scenarios. The antenna is analyzed completely using finite difference time domain (FDTD) method while the interaction is performed using the CST Microwave Studio software.
Synthesis and Anticancer Properties of Silver(I) Complexes Containing 2,6-Bis(substituted)pyridine Derivatives
Korany A. Ali,Mokhles M. Abd-Elzaher,Khaled Mahmoud
International Journal of Medicinal Chemistry , 2013, DOI: 10.1155/2013/256836
Synthesis and Anticancer Properties of Silver(I) Complexes Containing 2,6-Bis(substituted)pyridine Derivatives
Korany A. Ali,Mokhles M. Abd-Elzaher,Khaled Mahmoud
International Journal of Medicinal Chemistry , 2013, DOI: 10.1155/2013/256836
Abstract: Several new 2,6-bis(substituted)pyridine ligands and 2,6-bis(substituted)pyridine Ag(I) nitrate complexes were synthesized and characterized spectroscopically. The newly synthesized ligands include pyridine-2,6-bis(3-oxopropanenitrile) (1), pyridine-2,6-bis(2-cyano-N-phenyl-3-oxopropanethioamide) (2), and pyridine-2,6-bis((E)-2-(2-phenylhydrazono)-3-oxopropanenitrile) (3). The newly synthesized ligands and silver(I) complexes were evaluated for their in vitro anticancer activity against four human cancer cell lines including hepatocellular carcinoma (HePG2), lung adenocarcinoma (A549), colon carcinoma (HT29), and breast adenocarcinoma (MCF7). Most of the newly synthesized silver(I) complexes exhibited better activity than the ligands, and the results have been compared with doxorubicin as a reference drug. 1. Introduction Chemical and biological activity of the organic complexes is not possessed only by the metal or organic ligand but also this activity can be fine-tuned by subtle changes in the electronic and steric properties of the complexes or by variation of the oxidation state of the metal. These features provide a versatile platform for drug design that is now being exploited in several areas. For centuries, silver compounds have been known to possess interesting biological properties that show potent antibacterial properties [1–4]. Also, they were popular remedies for tetanus and rheumatism in the 19th century and for colds and gonorrhea before the advent of antibiotics in the early part of the 20th century [5]. Additionally, silver compounds used for treating mental illness, epilepsy, and nicotine addiction [6, 7]. Furthermore, silver compounds have reemerged as a viable treatment option for infections encountered in burns, open wounds, and chronic ulcers [8–11]. On the other hand, functionalized pyridine derivatives are gaining a great deal of interest in medicinal and organic synthesis, where some of pyridine derivatives are used as bactericides [12], fungicides [13], and anticancer agents [14–17]. In view of these observations and in continuation of our current interest in the synthesis of organic compounds for biological evaluations [18–25] and our interest in the chemistry of 2,6-disubstituted pyridine derivatives [26–29], we described herein a facile synthesis of novel silver complex with some of the newly synthesized 2,6-disubstituted pyridine ligands. The newly synthesized compounds were evaluated for their in vitro anticancer activity against four human cancer cell lines including hepatocellular carcinoma (HePG2), lung adenocarcinoma
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

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.

Design Bluetooth and Notched-UWB E-Shape Antenna Using Optimization Techniques
Ahmed M. Montaser;Korany Ragab Mahmoud;Adel B. Abdel-Rahman;Hamdy A. Elmikati
PIER B , 2013, DOI: 10.2528/PIERB12101407
Abstract: In this article, an optimized E-shaped patch antenna for Bluetooth (2.4-2.484 GHz) and UWB (3.1-10.6 GHz) applications with WLAN (5.15-5.825 GHz) band-notched characteristics is proposed. The dimensions of the E-shaped antenna structure in addition to the position of the slotted C-shape in the ground plane are optimized using recent optimization techniques such as Modified Particle Swarm Optimization (MPSO), Bacterial Swarm Optimization (BSO), and Central Force Optimization (CFO). The optimization algorithms were implemented using MATLAB-software and linked to the CST Microwave Studio to simulate the antenna. Next, the effects of the Laptop structure on the antenna radiation characteristics are considered. Finally, the antenna structures are simulated by the finite difference time domain method (FDTD) to validate the results. The measured results exhibit good agreement with the simulation from CST and the Finite Difference Time Domain (FDTD) program written with matlab.
White Dwarf Stars as a Polytropic Gas Spheres
M. I. Nouh,A. S. Saad,M. M. Elkhateeb,B. Korany
Physics , 2014,
Abstract: Due to the highly degeneracy of electrons in white dwarf stars, we expect that the relativistic effects play very important role in these stars. In the present article, we study the properties of the condensed matter in white dwarfs using Newtonian and relativistic polytropic fluid sphere. Two polytropic indices (namely n=3 and n=1.5) are proposed to investigate the physical characteristics of the models. We solve the Lane-Emden equations numerically.. The results show that the relativistic effect is small in white dwarf stars.
Page 1 /468699
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.