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The results of applying a novel microfluidic optical cytometer to generate and observe the light scattered from biological cells over a wide range of angles are presented. This cytometer incorporates a waveguide that increases the intensity of the scattered light to the extent that an inexpensive digital camera can be used to detect the light over a large solid angle. This device was applied to yeast cells and latex beads and experimental data were compared with the results of a finite difference time-domain (FDTD) method of simulation. The simulated scattering patterns were calculated from reported values of optical parameters and are in good qualitative agreement with experiment. It is demonstrated that this system could be used to acquire information on the microstructure and potentially the nanostructure of cells.

Biological cells are complex in both morphological and biochemical structure. The effects of cellular fine structure on light scattered from cells are studied by employing a three-dimensional code named AETHER which solves the full set of Maxwell equations by using the finite-difference time-domain method. It is shown that changes in cellular fine structure can cause significant changes in the scattered light pattern over particular scattering angles. These changes potentially provide the possibility for distinguishability of cellular intrastructures. The effects that features of different intrastructure have on scattered light are discussed from the viewpoint of diagnosing cellular fine structure. Finally, we discuss scattered light patterns for lymphocyte-like cells and basophil-like cells.

Inefficient resource management may cause problems of reliability of service in shared medium wireless networks. Resources include bandwidth, processor cycles and buffers. Excessive competition for these resources can cause severe packet collision rates, compound network congestion, or even result in starvation of some nodes. In such a situation, data transmission is subject to very long delays and significant packet losses. Although transport layer protocols can help improve end-toend performance, these approaches are slow in responding to network changes and incur additional overhead. This paper aims to reduce transmission delay and increase packet delivery ratio. A hybrid resource allocation problem is formulated by the Primal algorithm and a controller is derived to decrease congestion globally and to reduce collisions locally. Our simulation results show that this hybrid controller can achieve packet loss rates close to 1% and significantly shorten end-to-end delay even in a high interference environment with heavy system load. In addition, we also compare the performance of the hybrid controller with the impact of multipath routing. The accuracy of our simulation is improved by adding a probabilistic preamble detection model and SINR collision model based on frame error rate.

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