Physics Commons^™

On The Orientation Dependence Of The Casimir Force, Christopher David Markle

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In the 83 years of its development, Casimir force theory has seen many advances.

However, there still exists a need for more comprehensive approaches, particularly to complex geometries. To this end we have developed an approach to the Casimir force and demonstrated its use in predicting the Casimir force present in many cases such as the case of a single hollow sphere, finite size parallel plates, and anisotropic conductors.

Within the field of Casimir force experimentation, many predicted characteristics have not yet been demonstrated. To that end, we are performing an experiment designed to investigate the orientational dependence of the …

Assessing Functional Deficits At Optic Neuritis Onset In Eae Mice Using Manganese-Enhanced Mri (Memri) And Diffusion Fmri, Tsen-Hsuan Lin

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Optic neuritis: ON) is frequently a first sign of multiple sclerosis: MS), which is an inflammatory demyelinative disease of the central nerve system: CNS), including brain, optic nerve, and spinal cord. Investigating ON provides an approach to improve MS diagnosis and treatment monitoring. Experimental autoimmune encephalomyelitis: EAE) is a widely used animal model of MS and exhibits pathologies similar to the human disease. Magnetic resonance imaging: MRI) is a non-invasive tool to detect disease progress and as a standard diagnose procedure for MS in the clinic. In biological samples, the hydrogen nuclei are used to produce the MR signal due …

High Pressure Studies Of Superconductivity, Narelle Jayne Hillier

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Superconductivity has been studied extensively since it was first discovered over 100 years ago. High pressure studies, in particular, have been vital in furthering our understanding of the superconducting state. Pressure allows researchers to enhance the properties of existing superconductors, to find new superconductors, and to test the validity of theoretical models. This thesis presents a series of high pressure measurements performed in both He-gas and diamond anvil cell systems on various superconductors and on materials in which pressure-induced superconductivity has been predicted. Under pressure the alkali metals undergo a radical departure from the nearly-free electron model. In Li this …

Thermophysical And Structural Measurements Of Liquid Metallic Alloys Using Electrostatic Levitation, James Christopher Bendert

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In the study of the glass transition, the properties of high temperature liquids in their equilibrium and supercooled states may provide clues to the question of why certain compositions form glasses more easily than others. In metallic alloys such measurements are difficult due to the high reactivity and high melting temperatures of these liquids. Levitation methods provide a solution this problem by isolating liquid alloys from their environments. Here, the techniques of data acquisition and analysis for thermophysical property measurements under electrostatic levitation are presented, with demonstrative examples from select compositions from the Cu-Zr system. The development of techniques and …

Actomyosin Contractility In Nonmuscle Cells, Nilushi Lakmali Dasanayake

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Forces and stresses generated by the action of myosin minifilaments are analyzed via simulation of their motion in idealized computer-generated random, isotropic actin networks and actin bundles. The networks and bundles are generated as random collections of actin filaments in two dimensions with constrained orientations, crosslinked and attached to fixed walls: four walls for isotropic networks, two for bundles). Myosin minifilaments are placed on actin filament pairs and allowed to move and deform the network so that it exerts forces on the walls.

The stresses are overwhelmingly contractile in both cases, because minifilament equilibrium positions having contractile stress have lower …