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Arish, Egypt

Zaky D.S.E.,Al - Azhar University of Egypt | El-Nahrery E.M.A.,Suez University
International Immunopharmacology | Year: 2016

Background IL-23 is a pro-inflammatory cytokine belonging to the IL-12 cytokine family. IL-23 is essential for the differentiation of Th17 lymphocytes, a subtype of T lymphocyte implicated in chronic inflammatory/autoimmune mediated diseases. Experimental models of arthritis and clinical indications have highlighted an important role for Th17 lymphocytes in the pathogenesis of RA. However the role and mechanism of action of IL-23 in the pathogenesis of RA are still not fully understood. Objective This study was conducted to assess the level of IL-23 in patients with RA as well as the relationship between the IL-23 level and disease activity. Methods The study includes 77 patients with RA fulfilling the American College of Rheumatology (ACR) revised criteria for diagnosis of RA as well as 25 age and sex matched healthy subjects as controls. Patients were divided according to disease activity into four groups: DAS 28 score (∗ 2.6), 10 patients in remission, DAS 28 score between 2.6-3.2, 10 patients with low disease activity, DAS 28 score ranges between (3.2-5.1), 30 patients with moderate disease activity and DAS 28 score (∗ 5.1), 27 patients with High disease activity. Disease activity were determined by the 28-joint disease activity score (DAS 28). Anti-citrullinated protein antibodies (ACPA) was done. The levels of IL-23 were determined by enzyme-linked immunosorbent assay (ELISA). Results Serum level of IL-23 was significantly elevated in RA patients (78.92 ± 52.47) compared to control group (33.34 ± 3.99) (P < 0.001). However, no correlations were found between IL-23 and DAS 28 score, and other patients characteristics. Conclusion Our results imply that IL-23 may potentially play a role in the pathogenesis of RA and may be a useful biomarker for the diagnosis of this disease. Targeting the IL-23 cytokine may provide a new therapeutic approach in the treatment of RA. © 2015 Elsevier B.V. All rights reserved. Source

Kayid M.,King Saud University | Kayid M.,Suez University | Ahmad I.A.,Oklahoma State University | Izadkhah S.,Ferdowsi University of Mashhad | Abouammoh A.M.,King Saud University
IEEE Transactions on Reliability | Year: 2013

The purpose of this paper is to enhance the study of the mean time to failure (MTTF) order in an age replacement model, and the decreasing mean time to failure (DMTTF) class of life distributions. We present new characterizations of the MTTF order in terms of the well-known hazard rate and reversed hazard rate orders. Preservation properties of this order under some reliability operations such as monotonic transformations, mixture, and weighted distributions are investigated. In this context, we provide new results related to the DMTTF class. Finally, the problem of testing exponentiality against such class is discussed, and some numerical results are presented. © 2013 IEEE. Source

Izadkhah S.,Ferdowsi University of Mashhad | Kayid M.,King Saud University | Kayid M.,Suez University
IEEE Transactions on Reliability | Year: 2013

Based on the comparison of a certain function of mean inactivity times of two nonnegative random variables, we introduce and study a new stochastic order. Several elementary and then basic preservation properties of the new stochastic order under reliability operations of convolution, mixture, and shock models are discussed. We also derive characterizations of some well-known stochastic orders by the new order, and point out some results related to the weighted distributions. Some examples are included to illustrate the concepts. © 2012 IEEE. Source

Kareem W.A.,Suez University | Kareem W.A.,King Khalid University | Nabil T.,Suez Canal University | Nabil T.,King Khalid University | And 2 more authors.
Computers and Mathematics with Applications | Year: 2013

Harmonic analysis filtering methods are used to decompose 3D forced and decaying turbulent fields into coherent and incoherent parts. The filtering methods are the curvelets, wavelet and dual-tree complex wavelet filtering techniques. The methods are applied against the velocity fields of forced and decaying homogeneous isotropic turbulence. The velocity fields are generated using the Lattice Boltzmann Method (LBM) with a resolution of 1283 where the Taylor micro-scale Reynolds numbers are 72 and 29 for forced and decaying fields, respectively. The main objective of this study is to use other different filtering methods rather than depending only on wavelet and Fourier decompositions. Using different filtering methods may help in turbulence modeling, improving our knowledge about the structure of turbulent flow, choosing the appropriate filtering method and extracting general characteristics of the flow under study. Results show that the coherent and the random incoherent fields contribute to all scales in the inertial range, but the statistical behavior is different for each field. The three filtering methods approximately identify the coherent fields with the same geometrical shapes of the organized vortical structures. The statistical properties such as flatness, skewness and spectrum of the extracted fields (coherent and incoherent parts) are also investigated for each filtering method. The joint PDFs between the third and second invariants of the velocity gradient tensor are also studied. The joint PDFs for the coherent parts are found similar to previous topological studies of isotropic turbulence; however the incoherent PDFs show different topological features. © 2013 Elsevier Ltd. All rights reserved. Source

Bhran A.A.,Suez University | El-Gharbawy M.M.,Egyptian Propylene and Polypropylene Company
Journal of Natural Gas Science and Engineering | Year: 2016

The expected conversion and selectivity of the investigated propane dehydrogenated plant were not achieved due to many causes. One of causes is the inefficient performance of the gas separation and fractionation unit especially the deethanization process. Thus, the primary goal of the present work is to increase the propane and propylene recoveries as well as to overcome some operational problems of this process. In order to accomplish this goal, a change in the process configuration and in some operating conditions was suggested. The simulation tool used in this study to examine the proposed modifications is HYSYS version 8.0 with Peng-Robinson Equation of State (EoS). The validity of simulation is proved by the good correspondence between laboratory and simulation results of the modified plant. The benefits of this study were realized when our proposed modification was applied to the original plant. The results show that the modified plant in operation is capable of recovering 2235 tons/year of propane and propylene more than the original plant. It is also noted that more ethane and ethylene are separated in the modified plant. Furthermore, the modified process provides a solution to some operational problems like increased carryover in the deethanizer rectifying column. The last part of this work considered the investigation of the maximum feed stream CO2 concentration at which the plant can operate properly without freezing. © 2016 Elsevier B.V.. Source

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