Actin Sequences and Associated Elements in the Mouse Genome

This work describes the structural analysis of four mouse genomic clones which had previously been shown by electron microscopic heteroduplex analysis to contain actin-like genes, each with a single interruption. The objective of this work was to determine the nature of these interruptions

Regression modelling of cervical cancer and Chlamydia incidence in the context of national screening programmes

Prevention of cervical cancer development or reduction in undetected Chlamydia incidence and further onward Chlamydia transmission can be achieved through regular screening. Early detection through a regular screening programme is essential to achieve this goal. A well established screening policy is needed to improve screening efficiency.This PhD study demonstrated the use of mathematical and spatial modelling to explore the risk factors through various regression models, to explore the relation between socio-economic conditions and disease incidence, and also other techniques including classification analysis, decision models, and simulation to evaluate screening options. Based on the risk factors and risk grouping, different groups may have different screening policies. Alternatively, geographical differences can be taken into account by dividing areas into a few parts; the population living in each part may be considered to have different risks of developing cervical cancer or Chlamydia in their life time. Therefore, different screening programmes and services could be provided to those populations according their location or the risk groups which they belong to

Slow Adaptive OFDMA Systems Through Chance Constrained Programming

Adaptive OFDMA has recently been recognized as a promising technique for providing high spectral efficiency in future broadband wireless systems. The research over the last decade on adaptive OFDMA systems has focused on adapting the allocation of radio resources, such as subcarriers and power, to the instantaneous channel conditions of all users. However, such "fast" adaptation requires high computational complexity and excessive signaling overhead. This hinders the deployment of adaptive OFDMA systems worldwide. This paper proposes a slow adaptive OFDMA scheme, in which the subcarrier allocation is updated on a much slower timescale than that of the fluctuation of instantaneous channel conditions. Meanwhile, the data rate requirements of individual users are accommodated on the fast timescale with high probability, thereby meeting the requirements except occasional outage. Such an objective has a natural chance constrained programming formulation, which is known to be intractable. To circumvent this difficulty, we formulate safe tractable constraints for the problem based on recent advances in chance constrained programming. We then develop a polynomial-time algorithm for computing an optimal solution to the reformulated problem. Our results show that the proposed slow adaptation scheme drastically reduces both computational cost and control signaling overhead when compared with the conventional fast adaptive OFDMA. Our work can be viewed as an initial attempt to apply the chance constrained programming methodology to wireless system designs. Given that most wireless systems can tolerate an occasional dip in the quality of service, we hope that the proposed methodology will find further applications in wireless communications

Wide field-of-view microscope based on holographic focus grid illumination

We have developed a new microscopy design that can achieve wide field-of-view (FOV) imaging and yet possesses resolution that is comparable to a conventional microscope. In our design, the sample is illuminated by a holographically projected light-spot grid. We acquire images by translating the sample across the grid and detecting the transmissions. We have built a prototype system with an FOV of 6mm×5mm and acquisition time of 2.5s. The resolution is fundamentally limited by the spot size—our demonstrated average FWHM spot diameter was 0.74μm. We demonstrate the prototype by imaging a U.S. Air Force target and a lily anther. This technology is scalable and represents a cost-effective way to implement wide FOV microscopy system

Expression of human cathepsin B protein in Escherichia coli

AbstractA cDNA fragment containing the coding sequence for the mature enzyme of human lysosomal proteinase cathepsin B was inserted in the pET plasmid expression vectors, so that it was placed under the control of transcription and translation signals from bacteriophage T7. Upon induction, cathepsin B antigen was detected by in situ immunoscreening of lysed E. coli and by Western blot analysis of bacterial lysates. To our knowledge this is the first report of abundant synthesis of cloned cathepsin B in any expression system. Subfragments of cathepsin B can also be generated by this technique and will be used to study cathepsin B structure and function