http://hdl.handle.net/10540/86075 Sun, 26 May 2013 07:58:39 GMT 2013-05-26T07:58:39Z http://hdl.handle.net/10540/283912 Title: Poison in party pills is too much to swallow Authors: Cole, Mike Abstract: The harm caused by designer drugs justifies the law's attempts to keep pace with underground chemists. Wed, 15 Jun 2011 00:00:00 GMT http://hdl.handle.net/10540/283912 2011-06-15T00:00:00Z http://hdl.handle.net/10540/276316 Title: The effect of altering spherical aberration on the static accommodative response Authors: Theagarayan, Baskar; Radhakrishnan, Hema; Allen, Peter M.; Calver, Richard I.; Rae, Sheila M.; O'Leary, Daniel J. Abstract: PURPOSE To investigate the effect of altering the spherical aberration (SA) of the eye on the static accommodative response. METHODS: Participants were fitted with nominally afocal contact lenses with controlled amounts of SA of either -0.2, -0.1, 0.0, +0.1 or +0.2 microm for a 5-mm pupil. Measurements of SA and root mean square (RMS) total aberration for the eye plus lens for each participant were determined with a Complete Ophthalmic Analysis System aberrometer. Accommodation was stimulated either by placing targets at different dioptric distances from the eye, or by using a fixed distance target and placing negative-powered lenses in front of the eye. Accommodation responses were determined with a Shin-Nippon autorefractor. RESULTS: For both stimuli situations, the slope of the accommodation stimulus-response function was lowest for the lenses with +0.2 microm SA, and increased as the amount of SA was reduced. There was a significant negative correlation between SA and slope. Lag of accommodation at 33 cm correlated well with added SA, but did not correlate with total RMS error. There was no significant difference between the responses at 30 min after lens wear started and the responses after 1 h. CONCLUSIONS: Adding negative SA to the eye generally improves the slope of the accommodation stimulus-response curve and decreases lag of accommodation, and positive added SA depresses the slope of the stimulus-response curve and increases lag. The effect seems to be specific to SA, as there was no relationship between lag and RMS error. Altering SA may be a viable way of changing accommodative functions in clinical situations. Description: The definitive version is available at www3.interscience.wiley.com. Thu, 01 Jan 2009 00:00:00 GMT http://hdl.handle.net/10540/276316 2009-01-01T00:00:00Z http://hdl.handle.net/10540/266492 Title: Aberration control and vision training as an effective means of improving accommodation in individuals with myopia Authors: Allen, Peter M.; Radhakrishnan, Hema; Rae, Sheila M.; Calver, Richard I.; Theagarayan, Baskar Pitty; Nelson, Paul; Osuobeni, Ebi P.; Sailoganathan, Ananth; Price, Holly C.; O'Leary, Daniel J. Abstract: To test the efficacy of a novel dual treatment for improving accommodative accuracy and dynamics in young persons with myopia. Description: The full article can be found here: http://www.iovs.org/content/50/11/5120 Sun, 01 Nov 2009 00:00:00 GMT http://hdl.handle.net/10540/266492 2009-11-01T00:00:00Z http://hdl.handle.net/10540/264072 Title: The effect of high tibial osteotomy on stress in the tibio-femoral joint: a computer simulation study Authors: Reisse, F.; Walker, R.W.; Carpanen, D.; Dowell, John K.; Dewan, Z.; Imhauser, C.; Hillstrom, Howard; Mootanah, R. Abstract: Osteoarthritis (OA) is a degenerative disease of all of the tissues within the diarthrodial joint and one of the leading causes of disability. Knee OA is often caused by lower limb malalignment, high body mass index, and injury to the surrounding soft tissues, resulting in a cyclic degradation of the joint. High tibial osteotomy (HTO) is a realignment surgery to restore knee function and minimise excessive loading. However, the link between malalignment and stress in the knee is not well understood and surgical outcomes by HTO have been unpredictable. Therefore the overarching goal is to develop a three-dimensional virtual surgery finite element (FE) model that integrates subject specific imaging and computational biomechanics to predict the effects of different realignment techniques on knee joint contact stress. FE models of a cadaveric knee joint were created from magnetic resonance images, using Mimics v14 (Materialise, Belgium). Following non-manifold assembly, these 3D models were exported to Abaqus 6.11 to determine the stress distribution within the medial-lateral compartments of the well-aligned knee. A 10° open wedge HTO was performed to simulate the malaligned knee. Boundary conditions of 300N axial load and 12 Nm bending moment were applied to simulate posture in the well aligned and malaligned knee. Peak compressive stress in the malaligned knee was 60% higher than that of the well-aligned knee. This excessive stress is considered a primary factor for the onset and progression of OA. These results highlight the importance of understanding the effects of HTO on the knee joint contact stresses in order to delay OA progression. Sun, 01 Apr 2012 00:00:00 GMT http://hdl.handle.net/10540/264072 2012-04-01T00:00:00Z