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Molten globules are compact intermediates in the protein folding process which retain native- like secondary structure, but have a fluctuating ensemble of tertiary folds. Human alpha-lactalbumin is a Ca2+ binding protein which forms a molten globule at pH 2. Although much is known about the secondary structure of the alpha-lactalbumin molten globule, the tertiary structure has so far not been elucidated. Presented in Chapter 2 is a double electron-electron resonance study of alpha-lactalbumin. The C-helix was found to be fully folded in the molten globule, in agreement with previous studies. Furthermore, it is also shown that both the N- and C-termini are in close proximity to the C-helix, forming part of the hydrophobic core of the protein. Data collected in the presence of 8M urea show that the protein is unfolded under these conditions, and distinguishes the molten globule state from this. These data provide quantitative information about the tertiary structure of the alpha-lactalbumin molten globule, and may provide important insight into the protein folding process. Although a wide variety of chemical and biological systems are known to be sensitive to the strength of an applied magnetic field, no biological systems, such as the cryptochrome proteins believed to be the magnetoreceptors in migratory birds, have yet been shown to be sensitive to the field direction. Traditionally, the anisotropic response of such systems to the magnetic field has been probed using photoselection or alignment with liquid crystals. The experimental sensitivity to anisotropy could, however, be improved by increasing the degree of molecular alignment, such as by crystallisation. Presented in Chapter 3 is a study of hen egg white lysozyme crystals doped with FMN, which together form a magnetically sensitive system. The crystals were studied using confocal microscopy, with the magnetic field effect being spatially resolved. The diffusion of FMN through the crystals was also studied, with the spatial variation of the magnetic field effect being explained with reference to the diffusion of FMN. Although no anisotropy of the magnetic field effect was observed in this system, the use of crystallisation as a method of controlling molecular orientation is potentially useful in systems which are expected to show anisotropy (such as cryptochrome). The behaviour of many chemical systems differs between the bulk solution and at the interface. These interfacial processes can be difficult to probe using conventional absorption spectroscopy due to the relatively low absorbance of species at the interface as compared to the bulk. Cavity ring down and cavity enhanced absorption spectroscopy are two techniques which increase the sensitivity of absorption measurements, and evanescent wave variants of both have been applied to interfacial studies. Presented in Chapter 4 is a polarisation sensitive, broad band, evanescent wave cavity enhanced absorption experiment, which allows the study of the spectra of species at the silica/solvent interface across the visible region. A variety of systems which show interesting inter- facial behaviour have been studied, including crystal violet at the silica/water interface, and with polyelectrolyte films. The data could be fitted to extract spectra, kinetics, and average orientations of three individual species. These studies demonstrate the power of the polarisation sensitive, broad band nature of this experiment in determining complex interfacial behaviour involving more than one species.

The Kansas Applied Remote Sensing (KARS) Program and Department of Geography- Meteorology have developed an interactive digital image processing program package that runs on the University of Kansas central computer. The module form and simple Fortran programming of the package has allowed easy and rapid upgrades and extensions of its capabilities. The package is comprised of sub image extraction and rectification, image display and enhancement, and both supervised and unsupervised classification routines. It has been used in both instructional and research settings at the University.

Today, CMOS Photonics technology has matured so that most waveguide based optical functions are available inside a CMOS die. While an integrated light source is still an outstanding problem, photodetection can be accomplished by the addition of pure germanium photodetectors to the CMOS process. These components have the potential to enable outstanding sensitivity levels when integrated monolithically with CMOS circuitry.

This talk discusses the technological challenges arising from the insertion of a Ge photodetectors step in a CMOS process and the advantages brought by monolithic integration.

This paper introduce the world's first, high-speed optical receiver using Ge waveguide photodetectors monolithically integrated in the CMOS process. The integrated receiver achieves a sensitivity of -14.2 dBm (10-12 BER) at 10 Gbps and 1550 nm.