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Computational Biophysics lies at the intersection between biology, physics, applied mathematics and software engineering. Some of the most burning questions in molecular biology are concerned with biomechanical systems, the dynamics of which are driven by chemistry and physics. Unfortunately, we have extremely limited means to observe these dynamics experimentally. In the past, this problem has been solved with the use of molecular dynamics, sometimes referred to as a `computational microscope'. Studying biomolecules in silico can provide a wealth of new information at temporal and spatial resolutions far beyond any current imaging modality. But molecular dynamics algorithms are limited by current computing power, and by the assumptions used to construct them. The kinetochore, a supramolecular structure crucial to the process of cell division, operates on time and length scales outside the reach of atomistic molecular dynamics with current computing power. To overcome this limitation, we propose a new, coarse-grained algorithm, which allows for a more computationally inexpensive representation of the biomolecules that comprise the kinetochore. This algorithm, KOBRA (KirchOff Biological Rod Algorithm) is designed to perform dynamical simulations of elongated biomolecules such as those containing alpha-helices and coiled-coils. It represents these as coarsely-discretised Kirchoff rods, with linear elements that can stretch, bend and twist independently. These rods can have anisotropic and inhomogeneous parameters and bent or twisted equilibrium structures, allowing for a coarse-grained parameterisation of complex biological structures. Each element is non-inertial and subject to thermal fluctuations. This coarse-grained representation allows for simulations of extremely large, long-lived systems at the biological mesoscale. KOBRA has been extended with a parameterisation scheme that allows for rod parameters (in terms of stretching, bending and twisting constants) to be extracted from all-atom simulation trajectories. An all-atom representation of Ndc80C - a sub-unit of the kinetochore - was constructed, and the KOBRA parameters for the molecule were extracted from its trajectory. The KOBRA algorithm is validated against both the physics of elastic rods and the biology of Ndc80C and the kinetochore. A partial kinetochore system was constructed and simulated using KOBRA and FFEA (Fluctuating Finite Element Analysis). The resulting trajectories were analysed and used to investigate the microtubule-binding ability of Ndc80C in a variety of configurations. A C++ implementation of KOBRA is available under the GNU GPLv3 free software licence, and can http://ffea.bitbucket.io.

The contents of this thesis can be divided into three parts. The first concerns the adult Aleochara. A key is provided for the identification of the 27 British species which are fully described and their distribution mapped. The aedeagi and spermathecae of all species are figured and described. One species, A. ripicola, previously included in the British list, is deleted and another, A. verna, has been added to the list. The structure of the ovaries is described, compared with those of other Staphylinids, and correlated with the fecundity of the, female &leochara. The feeding habits, overwintering sites, and reactions of the adults to humidity gradients are described. The second part deals with the development and morphology of the immature stages. The 1st Jester larvae of 12 species were bred including 8 previously =described. The distribution of egg bursters and other chitinous granules on the larvae of 14 species arc figured and described ae a means of identification. Survival of starved let instar larvae and the sites of entry into the host puparium are investigated.

The research presented here is an exploratory investigation of the potential role of psychosexual factors in the development of the eating disorders anorexia and bulimia. The study sample involved 41 female eating disordered patients (16 anorexics and 25 bulimics), diagnosed using the DSM-III-R criteria. These patients were recruited from The Eating Disorders Program at St. Albans Psychiatric Hospital in Radford, Virginia. Five hypotheses were tested concerning the following psychosexual factors: sexual knowledge and attitudes; sexual experience and functioning; sex roles; gender identity (sexual orientation); and history of sexual abuse or incest. The hypotheses postulated that the psychosexual factors would exist or be perceived by eating disordered patients as significantly different than would be statistically expected according to available normative data. The instrumentation for measuring these factors included the Derogatis Sexual Functioning Inventory, the Bern Sex Role Inventory, and the Klein Sexual Orientation Grid. Compared to normative data, significant results were found in the total sample for all psychosexual factors except Sexual Knowledge and Gender Identity. However, no significant differences were found between the anorexic and bulimic subsamples. These results are discussed along with their implications for therapy and research.