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Radwan S. Farag Ebtesam A. Mahmoud Amany M. Basuny & Rehab F. M. Ali 《International Journal of Food Science & Technology》2006,41(7):790-798
Crude juice of olive leaves (Kronakii cultivar) was obtained by hydraulic press. The level of polyphenlic compounds in the juice was 215 ppm. An aliquots of the concentrated olive leaf juice, represent 600, 1200 and 2400 ppm as polyphenols and butylated hydroxy toluene (BHT; 200 ppm) were administered to rats daily for 6 weeks by stomach tube. The liver (aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase activities) and kidney (bilirubin, uric acid, creatinine and urea) function tests and serum contents (total lipids, total cholesterol and low and high‐density lipoproteins) were measured to assess the safety limits of the polyphenolic compounds in the olive leaf juice. The data of the aforementioned measurements indicated that the administration of olive leaf juice did not cause any changes in liver and kidney functions. On the contrary, BHT at 200 ppm induced significant increases in the enzyme activities and the serum levels of total lipids, uric acid, urea and creatinine. Microscopical examinations of kidney and liver tissues of rats administered with the phenolic compounds of olive leaf juice had the histological character as that of control rats whilst, the administration of BHT at 200 ppm altered the features of rat liver tissues and severely damaged the rat kidney tissues. 相似文献
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Mourad S. Semary Hany N. Hassan Ahmed G. Radwan 《Chemical Engineering Communications》2017,204(6):635-647
This paper discusses the diffusion and reaction behaviors of catalyst pellets in the fractional-order domain as well as the case of nth-order reactions. Two generic models are studied to calculate the concentration of reactant in a porous catalyst in the case of a spherical geometric pellet and a flat-plate particle with different examples. A controlled Picard analytical method is introduced to obtain an approximated solution for these systems in both linear and nonlinear cases. This method can cover a wider range of problems due to the extra auxiliary parameter, which enhances the convergence and is suitable for higher-order differential equations. Moreover, the exact solution in the linear fractional-order system is obtained using the Mittag–Leffler function where the conventional solution is a special case. For nonlinear models, the proposed method gives matched responses with the homotopy analysis method (HAM) solutions for different fractional orders. The effect of fractional-order parameter on the dimensionless concentration of the reactant in a porous catalyst is analyzed graphically for different cases of order reactions and Thiele moduli. Moreover, the proposed method has been applied numerically for different cases to predict and calculate the dual solutions of a nonlinear fractional model when the reaction order n?=??1. 相似文献
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Radwan S. Abujassar 《Wireless Personal Communications》2018,100(3):819-849
The Internet generation infrastructure is growing and moving towards a consistency model of high-speed nodes interconnected by optical core networks. Therefore, the interaction between IP and optical network layers, specifically, the routing and signalling aspects, are maturing and they can lead to enhance the services and network performance. At the same time, a consensus has emerged in the industry on utilizing IP-based protocols for the optical control plane. This paper defines a new technique for IP over Optical networks (interacting between bottom layers), considering both the IP-based control plane for optical networks as well as IP-optical network interactions (together referred to as “IP over optical networks”). In this paper, a new technique is proposed that reduces recovery time by making an interoperation between the data link layer (layer 2) with the network layer (layer 3). The proposed technique enables layer 2 with layer 3 to make a hybrid mechanism that improves the recovery time in the network through two cases (1st-Detection and 2nd-Rerouting). The technique involves detecting failure in less time through layer 2 and rerouting traffic through an alternative path between source and destination by using a new algorithm in layer 3 to deliver data packets without the need to wait for the routing protocol to update the network topology and compute the routing table. In case of the network recovery, layer 2 has demonstrated its capability to detect failure extremely quickly shown through the immediate detection of the loss of signals for the link or node. The recovery mechanism, i.e., the rerouting mechanism, which leads the node, switches the data packets through an adjacent node to its destination via the life node. The latter is created by the proposed mechanism before the occurrence of the failure. The aim of this mechanism is to avoid loss of packets, improve QoS and improve recovery time as we have shown in the results shown below. 相似文献
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Yousef Elarian Radwan Abdel-Aal Irfan Ahmad Mohammad Tanvir Parvez Abdelmalek Zidouri 《International Journal on Document Analysis and Recognition》2014,17(4):455-469
Handwriting synthesis is the automatic generation of data that resemble natural handwriting. Although handwriting synthesis has recently gained increasing interest, the area still lacks a stand-alone review. This paper provides classifications for the different aspects of handwriting synthesis. It presents the applications, techniques, and evaluation methods for handwriting synthesis based on the several aspects that we identify. Then, it discusses various synthesis techniques. To the best of our knowledge, this paper is the only stand-alone survey on this topic, and we believe it can serve as a useful reference for the researchers in the field of handwriting synthesis. 相似文献
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M. E. Fouda A.G. Radwan 《International Journal of Circuit Theory and Applications》2014,42(10):1092-1102
This paper introduces two voltage‐controlled memristor‐based reactance‐less oscillators with analytical and circuit simulations. Two different topologies which are R‐M and M‐R are discussed as a function of the reference voltage where the generalized formulas of the oscillation frequency and conditions for oscillation for each topology are derived. The effect of the reference voltage on the circuit performance is studied and validated through different examples using PSpice simulations. A memristor‐based voltage‐controlled oscillator (VCO) is introduced as an application for the proposed circuits which is nano‐size and more efficient compared to the conventional VCOs. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献