Mark A. Warren

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Male rats undernourished from the 18th day of gestation until 100 days of age were nutritionally rehabilitated until 200 days of age. Six control and six experimental rats at each of 12, 25, 50, 100, and 200 days of age were killed by perfusion with buffered 2.5% glutaraldehyde. Pieces of visual cortex from each rat were postfixed in osmium tetroxide and(More)
In this paper we present a molecular dynamics calculation of the Frank elastic constants of a nematic liquid crystal. We study two well-known variants of the Gay-Berne potential, and determine the elastic constants by measuring orientational fluctuations as a function of wavevector, using reasonably large system sizes in the range 1000–8000 molecules. For(More)
Black and white hooded Lister rats were undernourished for various times up to 150 days of age; some of them were nutritionally rehabilitated from 75 days. Undernourished rats weighed significantly less than well-fed controls at all ages studied. After embedding in resin, sections of cerebellar cortex were cut and examined at the light and electron(More)
In this paper we present the results of extensive molecular dynamics simulations of a model of liquid crystals, in which a twist is imposed on the direction of preferred orientation. On quenching the system from a twisted nematic phase to a state point within the Smectic-A phase, we observe a structure which corresponds closely to that of the smectic-A *(More)
The implementation of parallel molecular dynamics techniques is discussed in the context of the simulation of single-site anisotropic potentials. We describe the use of both replicated data and domain decomposition approaches to molecular dynamics and present results for systems of upto 65536 Gay-Berne molecules on a range of parallel computers (Transtech(More)
Male rats undernourished from the 18th day of gestation until 100 days of age were nutritionally rehabilitated until 200 days of age. Six control and six experimental rats at each of 100 and 200 days of age were killed by perfusion with buffered 2.5% glutaraldehyde. Pieces of visual cortex from each rat were postfixed in osmium tetroxide and embedded in(More)
Recent evidence showing alterations in spatial memory due to a period of undernutrition during early life has implicated the hippocampus as one of the brain centres that may be particularly adversely affected. However, there are very few quantitative morphological studies that have examined the neuronal and synaptic populations of the hippocampi from(More)