Moniem T.A.,MISR University for Science and Technology
Quantum Electronics | Year: 2017
A novel all-optical XNOR gate is proposed, which combines the nonlinear Kerr effect with photonic-crystal ring resonators (PCRRs). The total size of the proposed optical XNOR gate based on photonic crystals with a square lattice of silicon rods is equal to 35×21 mm. The proposed structure has a bandgap in the range from 0.32 to 0.44. To confirm the operation and feasibility of the overall system use is made of analytical and numerical simulation using the dimensional finite difference time domain (FDTD) and plane wave expansion (PWE) methods. © 2017 Kvantovaya Elektronika and Turpion Ltd.
Mohammed N.A.,MISR University for Science and Technology |
Elkarim M.A.,MISR University for Science and Technology |
Elkarim M.A.,Arab Academy for Science and Technology
Optics Express | Year: 2015
This work explores and evaluates the effect of diffuse light reflection on the accuracy of indoor localization systems based on visible light communication (VLC) in a high reflectivity environment using a received signal strength indication (RSSI) technique. The effect of the essential receiver (Rx) and transmitter (Tx) parameters on the localization error with different transmitted LED power and wall reflectivity factors is investigated at the worst Rx coordinates for a directed/overall link. Since this work assumes harsh operating conditions (i.e., a multipath model, high reflectivity surfaces, worst Rx position), an error of ≥ 1.46 m is found. To achieve a localization error in the range of 30 cm under these conditions with moderate LED power (i.e., P = 0.45 W), low reflectivity walls (i.e., ρ = 0.1) should be used, which would enable a localization error of approximately 7 mm at the room's center. ©2015 Optical Society of America.
Elsabahy M.,Texas A&M University |
Elsabahy M.,Assiut University |
Elsabahy M.,MISR University for Science and Technology |
Heo G.S.,Texas A&M University |
And 3 more authors.
Chemical Reviews | Year: 2015
The use of nanomaterials, in particular polymeric nanostructures, has demonstrated efficiency in improving delivery of diagnostic and therapeutic agents to the target sites, and the feasibility of incorporating several therapeutic/diagnostic/targeting moieties within specific compartments of the nanoparticles, with control of their navigation in the body and to the target sites. The greatest potential impact of polymeric nanoparticles toward imaging, in general, is the ability to increase contrast locally, by directing the biodistribution of high concentrations of packaged small-molecule contrast agents to a target organ/site in vivo, and also the possibility that multiple types of contrast agents can be coincidentally carried within a polymer nanoparticle package to achieve multimodality imaging. The intrinsic nature of the versatile construction and functionalization of polymeric nanoparticles has enabled facile and practical strategies for developing multimodal medical imaging that can compensate disadvantages of one imaging modality from another. There is an urgent need for collaboration between scientists from different disciplines for development of nanopharmaceuticals viable for clinical use because of the several challenges related to the clinical applications.
Azar A.T.,MISR University for Science and Technology |
El-Said S.A.,Zagazig University
Neural Computing and Applications | Year: 2014
Support vector machine (SVM) is a supervised machine learning approach that was recognized as a statistical learning apotheosis for the small-sample database. SVM has shown its excellent learning and generalization ability and has been extensively employed in many areas. This paper presents a performance analysis of six types of SVMs for the diagnosis of the classical Wisconsin breast cancer problem from a statistical point of view. The classification performance of standard SVM (St-SVM) is analyzed and compared with those of the other modified classifiers such as proximal support vector machine (PSVM) classifiers, Lagrangian support vector machines (LSVM), finite Newton method for Lagrangian support vector machine (NSVM), Linear programming support vector machines (LPSVM), and smooth support vector machine (SSVM). The experimental results reveal that these SVM classifiers achieve very fast, simple, and efficient breast cancer diagnosis. The training results indicated that LSVM has the lowest accuracy of 95.6107 %, while St-SVM performed better than other methods for all performance indices (accuracy = 97.71 %) and is closely followed by LPSVM (accuracy = 97.3282). However, in the validation phase, the overall accuracies of LPSVM achieved 97.1429 %, which was superior to LSVM (95.4286 %), SSVM (96.5714 %), PSVM (96 %), NSVM (96.5714 %), and St-SVM (94.86 %). Value of ROC and MCC for LPSVM achieved 0.9938 and 0.9369, respectively, which outperformed other classifiers. The results strongly suggest that LPSVM can aid in the diagnosis of breast cancer. © 2013 Springer-Verlag London.
Helmy M.M.F.,MISR University for Science and Technology
Infectious Disorders - Drug Targets | Year: 2010
Cyclosporiasis is a protracted, relapsing gastroenteritis and has a short recorded history. Cyclospora cayetanensis is an enigmatic parasite since its discovery highlights the need for isolation of cases of infection that could be part of widespread outbreaks. It is associated with diarrhoea among children in developing countries in the Americas, where C. cayetanensis is endemic; traveller's diarrhoea and/or food and waterborne outbreaks sometimes occur in the developed countries. In SubSaharan Africa and Egypt, cyclosporiasis has been reported to occur in both immunocompromised and immunocompetent patients. Zoonotic species of Cyclospora have also been identified worldwide in primates, indicating likely endemicity of this underreported disease. This can be attributed to the lack of awareness in the public and medical profession concerning the disease, which is, therefore, not routinely tested at the health centres. The correlation between the density of water contamination and the prevalence of cyclosporiasis among the individuals of each area is significant. No doubt, water is the main vehicle of transmission in the present community. Soil contact and poultry are significant risk factors. All literature on C. ayetanensis, cyclosporiasis worldwide, and endemic cyclosporiasis was searched from libraries, colleagues and internet. Although cyclosporiasis is considered an enigma worth unravelling, with many aspects of this disease and its transmission having been uncovered only recently, the situation has been rapidly changing since the disease first came to medical attention in the 1970s. © 2010 Bentham Science Publishers Ltd.
Azar A.T.,MISR University for Science and Technology
Neural Computing and Applications | Year: 2013
Measuring the blood urea nitrogen concentration is crucial to evaluate dialysis dose (Kt/V) in patients with renal failure. Although frequent measurement is needed to avoid inadequate dialysis efficiency, artificial intelligence can repeatedly perform the forecasting tasks and may be a satisfactory substitute for laboratory tests. Artificial neural networks represent a promising alternative to classical statistical and mathematical methods to solve multidimensional nonlinear problems. It also represents a promising forecasting application in nephrology. In this study, multilayer perceptron (MLP) neural network with fast learning algorithms is used for the accurate prediction of the post-dialysis blood urea concentration. The capabilities of eight different learning algorithms are studied, and their performances are compared. These algorithms are Levenberg-Marquardt, resilient backpropagation, scaled conjugate gradient, conjugate gradient with Powell-Beale restarts, Polak-Ribiere conjugate gradient and Fletcher-Reeves conjugate gradient algorithms, BFGS quasi-Newton, and one-step secant. The results indicated that BFGS quasi-Newton and Levenberg-Marquardt algorithm produced the best results. Levenberg-Marquardt algorithm outperformed clearly all the other algorithms in the verification phase and was a very robust algorithm in terms of mean absolute error (MAE), root mean square error (RMSE), Pearson's correlation coefficient (Rp 2) and concordance coefficient (RC). The percentage of MAE and RMSE for Levenberg-Marquardt is 0.27 and 0.32 %, respectively, compared to 0.38 and 0.41 % for BFGS quasi-Newton and 0.44 and 0.48 % for resilient backpropagation. MLP-based systems can achieve satisfying results for predicting post-dialysis blood urea concentration and single-pool dialysis dose spKt/V without the need of a detailed description or formulation of the underlying process in contrast to most of the urea kinetic modeling techniques. © 2012 Springer-Verlag London Limited.
Ahmed M.A.E.,MISR University for Science and Technology
Toxicology and Applied Pharmacology | Year: 2015
The wide abuse of the anabolic steroid nandrolone decanoate by athletes and adolescents for enhancement of sporting performance and physical appearance may be associated with testicular toxicity and infertility. On the other hand, taurine, a free β-amino acid with remarkable antioxidant activity, is used in taurine-enriched beverages to boost the muscular power of athletes. Therefore, the purpose of this study was to investigate the mechanisms of the possible protective effects of taurine on nandrolone decanoate-induced testicular and sperm toxicity in rats. To achieve this aim, male Wistar rats were randomly distributed into four groups and administered either vehicle, nandrolone decanoate (10. mg/kg/week, I.M.), taurine (100. mg/kg/day, p.o.) or combination of taurine and nandrolone decanoate, for 8. successive. weeks. Results of the present study showed that taurine reversed nandrolone decanoate-induced perturbations in sperm characteristics, normalized serum testosterone level, and restored the activities of the key steroidogenic enzymes; 3β-HSD, and 17β-HSD. Moreover, taurine prevented nandrolone decanoate-induced testicular toxicity and DNA damage by virtue of its antioxidant, anti-inflammatory, and anti-apoptotic effects. This was evidenced by taurine-induced modulation of testicular LDH-x activity, redox markers (MDA, NO, GSH contents, and SOD activity), inflammatory indices (TNF-α, ICAM-1 levels, and MMP-9 gene expression), intrinsic apoptotic pathway (cytochrome c gene expression and caspase-3 content), and oxidative DNA damage markers (8-OHdG level and comet assay). In conclusion, at the biochemical and histological levels, taurine attenuated nandrolone decanoate-induced poor sperm quality and testicular toxicity in rats. © 2014 Elsevier Inc.
Ahmed M.A.E.,MISR University for Science and Technology
Neurochemical Research | Year: 2014
The current study investigated the neuroprotective activity of idebenone against pilocarpine-induced seizures and hippocampal injury in rats. Idebenone is a ubiquinone analog with antioxidant, and ATP replenishment effects. It is well tolerated and has low toxicity. Previous studies reported the protective effects of idebenone against neurodegenerative diseases such as Friedreich's ataxia and Alzheimer's disease. So far, the efficacy of idebenone in experimental models of seizures has not been tested. To achieve this aim, rats were randomly distributed into six groups. Two groups were treated with either normal saline (0.9 %, i.p., control group) or idebenone (200 mg/kg, i.p., Ideb200 group) for three successive days. Rats of the other four groups (P400, Ideb50 + P400, Ideb100 + P400, and Ideb200 + P400) received either saline or idebenone (50, 100, 200 mg/kg, i.p.) for 3 days, respectively followed by a single dose of pilocarpine (400 mg/kg, i.p.). All rats were observed for 6 h post pilocarpine injection. Latency to the first seizure, and percentages of seizures and survival were recorded. Surviving animals were sacrificed, and the hippocampal tissues were separated and used for the measurement of lipid peroxides, total nitrate/nitrite, glutathione and DNA fragmentation levels, in addition to catalase and Na+, K+-ATPase activities. Results revealed that in a dose-dependent manner, idebenone (100, 200 mg/kg) prolonged the latency to the first seizure, elevated the percentage of survival and diminished the percentage of pilocapine-induced seizures in rats. Significant increases in lipid peroxides, total nitrate/nitrite, DNA fragmentation levels and catalase activity, in addition to a significant reduction in glutathione level and Na+, K+-ATPase activity were observed in pilocarpine group. Pre-administration of idebenone (100, 200 mg/kg, i.p.) to pilocarpine-treated rats, significantly reduced lipid peroxides, total nitrate/nitrite, DNA fragmentation levels, and normalized catalase activity. Moreover, idebenone prevented pilocarpine-induced detrimental effects on brain hippocampal glutathione level, and Na+, K+-ATPase enzyme activity in rats. Data obtained from the current investigation emphasized the critical role of oxidative stress in induction of seizures by pilocarpine and elucidated the prominent neuroprotective and antioxidant activities of idebenone in this model. © 2014 Springer Science+Business Media New York.
Azar A.T.,MISR University for Science and Technology
International Journal of Fuzzy System Applications | Year: 2012
Fuzzy set theory has been proposed as a means for modeling the vagueness in complex systems. Fuzzy systems usually employ type-1 fuzzy sets, representing uncertainty by numbers in the range [0, 1]. Despite commercial success of fuzzy logic, a type-1 fuzzy set (T1FS) does not capture uncertainty in its manifestations when it arises from vagueness in the shape of the membership function. Such uncertainties need to be depicted by fuzzy sets that have blur boundaries. The imprecise boundaries of a type-2 fuzzy set (T2FS) give rise to truth/membership values that are fuzzy sets in , , instead of a crisp number. Type-2 fuzzy logic systems (T2FLSs) offer opportunity to model levels of uncertainty which traditional fuzzy logic type1 struggles. This extra dimension gives more degrees of freedom for better representation of uncertainty compared to type-1 fuzzy sets. A type-1 fuzzy logic system (T1FLSs) inference produces a T1FS and the result of defuzzification of the T1FS, a crisp number, whereas a T2FLS inference produces a type-2 fuzzy set, its type-reduced fuzzy set which is a T1FS and the defuzzification of the type-1 fuzzy set. The type-reduced fuzzy set output gives decision-making flexibilities. Thus, FLSs using T2FS provide the capability of handling a higher level of uncertainty and provide a number of missing components that have held back successful deployment of fuzzy systems in decision making. Copyright © 2012, IGI Global.
Gewefel H.,MISR University for Science and Technology |
Salhia B.,Translational Genomics Research Institute
Clinical Breast Cancer | Year: 2014
Breast cancer is one of the most frequently diagnosed malignancy among adolescent and young adult (AYA) women, accounting for approximately 14% of all AYA cancer diagnoses and 7% of all breast cancer. Breast cancer in AYA women is believed to represent a more biologically aggressive disease, but aside from commonly known hereditary predispositions, little is still known about the underlying molecular genetic causes. This review examines the current trends of breast cancer in AYA women as they relate to clinical, social, genetic, and molecular pathologic characteristics. We highlight existing trends, treatment and imaging approaches, and health burdens as they relate to breast cancer in AYA women and provide a discussion on ways to help improve the overall management of this breast cancer cohort. © 2014 Elsevier Inc. All rights reserved.