W. Ahmed

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In today's embedded processors, performance and flexibility have become the two key attributes. These attributes are often conflicting. The best performance is obtained from custom designed integrated circuits. In contrast, the maximum flexibility is delivered by a general purpose processor. Among the architecture types emerged over the past years to strike(More)
In somatic cells, the position of the cell centroid is dictated by the centrosome. The centrosome is instrumental in nucleus positioning, the two structures being physically connected. Mouse oocytes have no centrosomes, yet harbour centrally located nuclei. We demonstrate how oocytes define their geometric centre in the absence of centrosomes. Using live(More)
Growing experimental evidence suggests that mechanical tension plays a significant role in determining the growth, guidance, and function of neurons. Mechanical tension in axons contributes to neurotransmitter clustering at the Drosophila neuromuscular junction (NMJ) and is actively regulated by neurons both in vitro and in vivo. In this work, we applied(More)
Vesicle transport in neurons is a highly complex nonequilibrium process. Their subcellular environment is undergoing constant fluctuations from thermal energy and molecular motors. Vesicle transport is an interplay between random motion (passive) and directed motion (active) driven by molecular motors along cytoskeletal filaments. It has been shown that(More)
Unlike traditional materials, living cells actively generate forces at the molecular scale that change their structure and mechanical properties. This nonequilibrium activity is essential for cellular function, and drives processes such as cell division. Single molecule studies have uncovered the detailed force kinetics of isolated motor proteins in-vitro,(More)
Effective intracellular transport of proteins and organelles is critical in cells, and is especially important for ensuring proper neuron functionality. In neurons, most proteins are synthesized in the cell body and must be transported through thin structures over long distances where normal diffusion is insufficient. Neurons transport subcellular cargo(More)
The original version of this Article contained an error in the title of the paper, where the word " fluorescence " was incorrectly given as " florescence ". This has now been corrected in the PDF and HTML versions of the Article. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in(More)
Living organisms are inherently out-of-equilibrium systems. We employ new developments in stochas-tic energetics and rely on a minimal microscopic model to predict the amount of mechanical energy dissipated by such dynamics. Our model includes complex rheological effects and nonequilibrium stochastic forces. By performing active microrheology and tracking(More)
1 Illumination can have adverse effects on live cells. However, many experiments, e.g. traction force microscopy, rely on fluorescence microscopy. Current methods to assess undesired photo-induced cell changes rely on qualitative observation of changes in cell morphology. Here we utilize a quantitative technique to identify the effect of light on cell(More)
With the emergence of microscale biotechnology, such as bio-microelectromechanical systems (" Bio-MEMS ") and micro-fluidic-based microchips for sensing and diagnostics, polydi-methylsiloxane (PDMS)-based elastomers have become very popular materials. [1] PDMS elastomers possess several features that are well suited for these applications: mechanical(More)