City of Scientific Research and Technological Applications

Alexandria, Egypt

City of Scientific Research and Technological Applications

Alexandria, Egypt

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Yassin A.M.,Genetic Engineering and Biotechnology Research Institute | El-Deeb N.M.,Genetic Engineering and Biotechnology Research Institute | Metwaly A.M.,Al - Azhar University of Egypt | El Fawal G.F.,Advanced Technology and New Materials Research Institute ATNMRI | And 3 more authors.
Applied Biochemistry and Biotechnology | Year: 2017

The aim of this investigation is to examine the anticancer activities of Balanites aegyptiaca fruit extract with its biogenic silver nanoparticles (AgNPs) against colon and liver cancer cells. B. aegyptiaca aqueous extract was fractionated according to polarity and by biosynthesized AgNP. The cytotoxicity of the extract, semi-purified fractions, and the AgNPs was examined on noncancerous cell lines. The safer fraction was subjected to ultra-performance liquid chromatography-MS to identify the major active constituents. The anticancer activities of the nontoxic doses of all the used treatments were tested against HepG2 and CaCo2 cells. The nontoxic dose of the B. aegyptiaca (0.63 mg/ml) extract showed high anti-proliferative activities against HepG2 and CaCo2 with a percentage of 81 and 77%, respectively. The butanol fraction was safer than the other two fractions with 46.3 and 90.35% anti-proliferative activity against Caco2 and HepG2 cells, respectively. The nontoxic dose of AgNPs (0.63 mg/ml) inhibits both HepG2 and Caco2 cells with a percentage of 84.5 and 83.4%, respectively. In addition, AgNPs regulate the expression of certain genes with folding higher than that of crude extract. Saponin-coated AgNPs showed great abilities to select the most anticancer ingredient(s) from the B. aegyptiaca extract with a more safety pattern than the polarity gradient fractionation. © 2017 Springer Science+Business Media New York

Khalifa A.,Virginia Polytechnic Institute and State University | Khalifa A.,National Telecommunication Institute | Azab M.,City of Scientific Research and Technological Applications | Eltoweissy M.,Virginia Military Institute
Proceedings - 2014 IEEE/ACM 7th International Conference on Utility and Cloud Computing, UCC 2014 | Year: 2014

The exponential growth of computational power and the advent of a multitude of energy-rich fixed and mobile nodes coupled with the emergence of modern resource management and virtualization technologies, Mobile Ad-hoc Clouds (MACs) are emerging as a viable computational asset. A major challenge is to construct MACs comprising highly dynamic, mobile, heterogeneous, fractionated, and scattered resources. Conventional resource virtualization technologies do not seamlessly consolidate such resources while adequately isolating the resource layer concerns from the executing code logic, which is key for MACs to operate and provision basic services. To this end, we propose Planet Cloud, a smart MAC management platform with an intrinsic support for highly mobile, heterogeneously-composed and dynamically-configured MACs. Planet Cloud enables MACs to autonomously adapt to real-time dynamic variation in its underlying infrastructure isolating the hardware and code management concerns. Such isolation enabled seamless task deployment, execution, migration, dynamic/adaptive resource allocation, and automated failure recovery. Analysis and simulation show that the proposed platform can safely and reliably provision and maintain the needed computational power for the MAC to operate in a highly dynamic mobile work environment. © 2014 IEEE.

ElMorsi A.,Mansoura University | Abdelkhalek A.,City of Scientific Research and Technological Applications | Alshehaby O.,Mansoura University | Hafez E.E.,City of Scientific Research and Technological Applications
Botany | Year: 2015

The Iris yellow spot virus (IYSV) is a viral pathogen of onions and causes severe damage and economic loss in affected onion crops. Pathogenesis-related (PR) genes are part of the innate immune response that onions harbour against viral diseases, which to date remains unclear. Using a sensitive and reliable real-time quantitative PCR method, the dynamic expression of five different genes in infected onions were investigated after biological inoculation with virulent isolate of Thrips tabaci (Lindeman). The transcription levels of PR1, PR2, PR3, PR4, and PR5 genes were highly expressed 1 day post inoculation (dpi). Furthermore, statistical analysis revealed a significant change in peak expression levels of PR1 after 8 dpi and PR3 after 9 dpi. In contrast, the expression level change for the other genes was only moderate. Further, we determined and ranked the expression stability of three reference genes (EF1-a, 18S rRNA, and b-actin) using geNorm and NormFinder. The overall analysis demonstrated that b-actin is the most informative gene, which can be utilised as an internal control for quantitative gene expression. Our study findings not only provide guidelines for selection of appropriate reference genes in virally infected onions, but also valuable information concerning immune response related genes associated with the initial plant defences against viral infection. Moreover, the PR1 gene appears to be a disease-specific gene related to the IYSV infection in onion tissues. © 2015, National Research Council of Canada. All rights reserved.

Abdalla K.F.,Tanta University | Kamoun E.A.,City of Scientific Research and Technological Applications | El Maghraby G.M.,Tanta University
Journal of Applied Pharmaceutical Science | Year: 2015

The objective of the current study was to optimize the composition of alginate beads to produce ambroxol hydrochloride alginate beads with optimum specifications. The study employed beads based on sodium alginate solution (2% w/v) as the main component with calcium chloride solution as crosslinking agent as the prototype beads. The beads were prepared by syringe method. The effect of viscosity modifiers on the morphology, entrapment efficiency and drug release was studied. The prototype beads were spherical semitransparent with entrapment efficiency (EE) of 23%. Incorporation of polyvinylpyrrolidone (PVP) as a viscosity modifier produced spherical semitransparent beads with higher EE values compared with the prototype. Addition of carboxymethyl cellulose (CMC) produced oval opaque beads which have larger size and higher EE values compared with the prototype beads or those containing PVP only. Replacement of CMC with hydroxypropyl methyl cellulose (HPMC) produced semitransparent spherical beads with significant increase in the EE. Monitoring the drug release rate from different beads, the all the tested beads were able to retain the drug in the stomach condition. In the intestinal conditions the release rate depended on the composition of the beads with prototype beads librating most of its contents in the first 15 minutes. Formulations containing either CMC or HPMC were able to retard the drug release in the intestinal phase. In conclusion the study developed beads with optimum entrapment and release of ambroxol hydrochloride. © 2015 Karam F. Abdalla et al.

Azab M.,City of Scientific Research and Technological Applications | Azab M.,Virginia Polytechnic Institute and State University | Eltoweissy M.,Virginia Military Institute | Eltoweissy M.,Virginia Polytechnic Institute and State University
Proceedings of the 2014 IEEE 15th International Conference on Information Reuse and Integration, IEEE IRI 2014 | Year: 2014

Cyber Physical Systems (CPS) promise advances towards smarter infrastructure systems and services, significantly enhancing their reliability, performance and safety. SmartGrids are a typical example of CPS. Current SmartGrids Monitoring, Analysis, Sharing, and Control (MASC) technologies offer disparate and largely inadequate services for the realization of effective, pervasive, and efficient smart grid defense. Most current technologies did not consider that cyber and physical convergence needs a new paradigm to treat cyber and physical components seamlessly. Further, information sharing was severely curtailed by enforcing parameter defense to preserve the privacy of the Target-of-Defense system (ToD). These limitations negatively impact the quality, reliability, survivability, and promptness of defense services. In this paper, we propose an evolutionary sensory and effecting tool, CyPhyMASC, towards realizing pervasive MASC for enhanced SmartGrid defense. CyPhyMASC is unique in that it acts as a generic middle layer between the Defense Service Provider(s) (DSPs) and the ToD(s) creating a uniform defense interface that hides ToD's scale and heterogeneity aspects from Control and Management. Such isolation and uniform representation facilitated interoperable defense services. CyPhyMASC intelligently mixes and matches heterogeneous tools and control logic from various sources towards continually evolving defense missions. CyPhyMASC is also elastic where situation-driven MASC solutions can be dispatched through a dynamic set of sensor and effector software capsules to the ToD rather than using pre-deployed MASC components. DSPs use CyPhyMASC to circulate these capsules into the ToD 'body' to provide pervasive and scalable MASC services. Using analysis and simulation, our results demonstrate that CyPhyMASC can enhance detection and resolution promptness and sensitivity to multi-threaded widespread attacks while conserving considerable amount of ToD resources. © 2014 IEEE.

Farag M.M.,Alexandria University | Azab M.,City of Scientific Research and Technological Applications | Mokhtar B.,Alexandria University
IEEE PES Innovative Smart Grid Technologies Conference Europe | Year: 2015

Security is a major challenge preventing wide deployment of the smart grid technology. Typically, the classical power grid is protected with a set of isolated security tools applied to individual grid components and layers ignoring their cross-layer interaction. Such an approach does not address the smart grid security requirements because usually intricate attacks are cross-layer exploiting multiple vulnerabilities at various grid layers and domains. We advance a conceptual layering model of the smart grid and a high-level overview of a security framework, termed CyNetPhy, towards enabling cross-layer security of the smart grid. CyNetPhy tightly integrates and coordinates between three interrelated, and highly cooperative real-time security systems crossing section various layers of the grid cyber and physical domains to simultaneously address the grid's operational and security requirements. In this article, we present in detail the physical security layer (PSL) in CyNetPhy. We describe an attack scenario raising the emerging hardware Trojan threat in process control systems (PCSes) and its novel PSL resolution leveraging the model predictive control principles. Initial simulation results illustrate the feasibility and effectiveness of the PSL. © 2014 IEEE.

Khalifa A.,Virginia Polytechnic Institute and State University | Azab M.,Virginia Polytechnic Institute and State University | Eltoweissy M.,City of Scientific Research and Technological Applications
CollaborateCom 2014 - Proceedings of the 10th IEEE International Conference on Collaborative Computing: Networking, Applications and Worksharing | Year: 2015

The emergence of Mobile Ad-hoc Clouds (MACs) promises more effective and collaborative elastic resource-infinite computing. However, the highly dynamic, mobile, heterogeneous, fractionized, and scattered nature of computing resources coupled with the isolated non-cooperative nature of current resource management systems make it impossible for current virtualization and resource management techniques to guarantee resilient cloud service delivery. In this paper, we present PlanetCloud, our MAC management platform with an intrinsic support for resilient, highly mobile, cooperative, and dynamically-configurable MACs. We use PlanetCloud for the construction and management of resilient hybrid MACs (HMACs) over mobile and stationary computing resources. PlanetCloud comprises a trustworthy fine-grained virtualization layer and a task management layer. PlanetCloud employs the concepts of application virtualization and fractionation using intrinsically-resilient and aware micro virtual machines, or Cells in our terminology, to encapsulate executable applicationfractions. Such employment isolates the running application from the underlying physical resource enabling seamless execution over heterogeneous resources, lightweight load migration, and low cost of failure. Integral to PlanetCloud is resource forecasting and selection mechanism, which provide a MAC with future appropriate resource availability in space and time. Further, these features enable a large set of mobile, heterogeneous, and scattered resources to collaborate through PlanetCloud smart management platforms that seamlessly consolidates such resources into a resilient HMAC. Using analysis and simulation, we evaluate a PlanetCloud-managed resilient HMAC. Results show that PlanetCloud can provision high level of resource availability transparently maintaining the applications' QoS while preventing service disruption even in highly dynamic environments. Additionally, results showed that our approach to minimizing the cost of failure and facilitating easy load migration elevates the resilience of the HMAC to a great extent. © 2014 ICST.

Abd-El-Naby B.A.,Alexandria University | Abdullatef O.A.,Pharos University in Alexandria | Khamis E.,City of Scientific Research and Technological Applications | El-Mahmody W.A.,Alexandria University
International Journal of Electrochemical Science | Year: 2016

The effect of cationic surfactant, cetyltrimethylammonium bromide (Cetrimide) as corrosion inhibitor for steel in 0.5 M H2SO4 has been studied. The inhibition efficiency has been determined by weight loss and electrochemical impedance spectroscopy (EIS) measurements. Adsorption of Cetrimide on carbon steel in 0.5 M H2SO4 obeyed Langumir, Florry-Huggins and the Kinetic-Thermodynamic model. Effect of Cetrimide on the activation parameters of the corrosion reaction of steel in 0.5 M H2SO4 has been measured and discussed.

Mokhtar B.,Alexandria University | Azab M.,City of Scientific Research and Technological Applications
Alexandria Engineering Journal | Year: 2015

Vehicular Ad hoc NETworks are special case of ad hoc networks that, besides lacking infrastructure, communicating entities move with various accelerations. Accordingly, this impedes establishing reliable end-to-end communication paths and having efficient data transfer. Thus, VANETs have different network concerns and security challenges to get the availability of ubiquitous connectivity, secure communications, and reputation management systems which affect the trust in cooperation and negotiation between mobile networking entities. In this survey, we discuss the security features, challenges, and attacks of VANETs, and we classify the security attacks of VANETs due to the different network layers. © 2015 Faculty of Engineering, Alexandria University. Production and hosting by Elsevier B.V.

Khalil M.H.,University of Louisville | Khalil M.H.,City of Scientific Research and Technological Applications | Sheta W.,University of Louisville | Sheta W.,City of Scientific Research and Technological Applications | Elmaghraby A.S.,University of Louisville
Proceedings of the 31st International Conference on Computers and Their Applications, CATA 2016 | Year: 2016

The popularity of cloud computing as an attractive alternative to classic Information processing systems has been growing. Cloud Computing offers various remotely accessible services to users either free or on a pay-as-you-go (PAYG) basis. To provide high level of reliability and availability in such large-scale systems, it is critical to detect, diagnose, and fix these failures as they happen. The failures can be attributed to high CPU usage, memory consumption, and network delay. Therefore, resource monitoring plays an important role in avoiding failures. CPU usage is mostly used by researchers to discover virtual machines failure. Resource provisioning and virtual machines or tasks migration are used to maintain task performance. This study focuses on Infrastructure as a Service (IaaS). We use an effective method for avoiding failures by using proactive method through live monitoring CPU usage and dynamic task migration. The performance of model evaluated by measuring execution time, CPU utilization, and makespan for VMs different virtual. This study applied dynamic task migration as management resource for predicting failure event. The proposed model decreases the average execution time, CPU utilization while, model has low performance with makespan. Our model was developed and tested using cloud computing simulator called CloudSim. Copyright ISCA.

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