Ahmed M. Mohamed

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How the direction of axon guidance is determined is not understood. In Caenorhabditis elegans the UNC-40 (DCC) receptor mediates a response to the UNC-6 (netrin) guidance cue that directs HSN axon development. UNC-40 becomes asymmetrically localized within the HSN neuron to the site of axon outgrowth. Here we provide experimental evidence that the direction(More)
Using off-the-shelf commodity workstations to build a cluster for parallel computing has become a common practice. In studying or designing a cluster of workstations one should have available a robust analytical model that includes the major parameters that determines the cluster performance. In this paper, we present such a model for evaluating a cluster's(More)
Jackson networks have been very successful in so many areas in modeling parallel and distributed systems. However, the ability of Jackson networks to predict performance with system changes remains an open question, since Jackson networks do not apply to systems where there are population size constraints. Also, the product-form solution of Jackson networks(More)
To understand how our brains function, it is necessary to know how neurons position themselves and target their axons and dendrites to their correct locations. Several evolutionarily conserved axon guidance molecules have been shown to help navigate axons to their correct target site. The Caenorhabditis elegans Eph receptor tyrosine kinase (RTK), VAB-1, has(More)
The Eph receptor tyrosine kinases (RTKs) are regulators of cell migration and axon guidance. However, our understanding of the molecular mechanisms by which Eph RTKs regulate these processes is still incomplete. To understand how Eph receptors regulate axon guidance in Caenorhabditis elegans, we screened for suppressors of axon guidance defects caused by a(More)
In studying or designing parallel and distributed systems one should have available a robust analytical model that includes the major parameters that determine the system performance. Jackson networks have been very successful in modeling parallel and distributed systems. However, they have their limitations. In particular, the product-form solution of(More)
Fuel cells, as highly efficient and environment-friendly power sources, have attracted ever-increasing research and development in the past few decades. Mathematical modeling and simulation are applied to examine the influence of the different physical and electrochemical phenomena occurring in the structure of the fuel cell during operation. Such(More)
The development and use of cluster based computing is increasingly becoming an effective approach for solving high performance computing problems. The trend of moving away from specialized traditional supercomputing platforms such as Cray / SGI T3E to cheap and general-purpose systems consisting of loosely coupled components is expected to continue. In [1],(More)
The NCK adaptor proteins are composed entirely of SH3 and SH2 domains and serve as protein interaction bridges for several receptors during signal transduction events. Here we report the molecular and genetic analysis of the Caenorhabditis elegans nck-1 gene. C. elegans nck-1 encodes two isoforms: NCK-1A and a shorter isoform that lacks the first SH3(More)
One of the most familiar SCADA (supervisory control and data acquisition) application protocols now is OPC protocol. This interface is supported by almost all SCADA, visualization, and process control systems. There are many research efforts tried to design and implement an approach to access an OPC DA server through the Internet. To achieve this goal they(More)