Francis Edward Mitchell. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 80-81 (2nd gp.)). / Acknowledgments --- p.iii / Summary --- p.iv / Introduction --- p.1 / Sharpness and contrast --- p.2 / Causes of unsharpness --- p.3 / Chapter i) --- Photographic unsharpness --- p.3 / Chapter ii) --- Movement unsharpness --- p.6 / Chapter iii) --- Geometric unsharpness --- p.8 / Chapter iv) --- Exposure unsharpness --- p.12 / Contrast factors --- p.15 / Chapter i) --- Subject/object contrast --- p.15 / Chapter ii) --- Radiation --- p.16 / Chapter iii) --- Film and screen --- p.18 / Chapter iv) --- Subjective --- p.20 / "How do we see ""Sharpness & Contrast"" ？" --- p.21 / Factors in perception --- p.26 / Chapter i) --- The individuals eyesight (and age) --- p.26 / Chapter ii) --- Light intensity --- p.26 / Chapter iii) --- Colour --- p.27 / Chapter iv) --- Pupil diameter --- p.27 / Chapter v) --- Size and shape of the object --- p.28 / Chapter vi) --- Eccentricity --- p.28 / Chapter vii) --- Edge enhancement --- p.29 / Chapter viii) --- Background luminance --- p.30 / Chapter ix) --- Maximising information retrieval from an image --- p.30 / Experiment I - Production of an image with controlled sharpness and contrast --- p.31 / Chapter i) --- Choice of film & cassette --- p.31 / Chapter ii) --- Prevention of movement unsharpness --- p.34 / Chapter iii) --- Prevention of parallax --- p.34 / Chapter iv) --- Control of penumbra --- p.35 / Chapter v) --- Verification of image unsharpness --- p.40 / Control of contrast --- p.46 / Radiography of test objects --- p.48 / Experiment II - Perception of sharpness at different contrast levels --- p.53 / Chapter i) --- Experiment --- p.53 / Chapter ii) --- "Viewing the data in terms of ""sharpness""" --- p.56 / Chapter iii) --- Viewing the data in terms of contrast levels --- p.61 / Analysis of data from an expanded group size (N=55) --- p.66 / Experiment III - Effect of room lighting conditions on the perception of sharpness --- p.69 / Overall conclusions --- p.78 / Bibliography --- p.79 / References --- p.80 / Appendix A (VBV calculation) --- p.82 / Appendix B (Line-pair test-tool) --- p.83 / Appendix C (Scattered radiation) --- p.85 / Photo-electric --- p.85 / Compton --- p.85 / Pair-production --- p.85 / Net result --- p.86 / Appendix D (Metal discs) --- p.87 / "Appendix E (OFD, magnification and penumbra)" --- p.88 / Appendix F (Processor developer temperature) --- p.90 / Appendix G (Viewing contrast-sharpness data) --- p.91 / Appendix H (Viewing conditions) --- p.92 / Appendix I (Comparison of data - light and dark viewing conditions) --- p.94 / Appendix J (Curix film & screens) --- p.97

Habitually poor posture can lead to repetitive strain injuries that lower an individual's quality of life and productivity. Slouching over computer screens and smart phones, asymmetric weight distribution due to uneven leg loading, and improper loading posture are some of the common examples that lead to postural problems and health ramifications. To help cultivate good postural habits, researchers have proposed slouching, balance, and improper loading posture detection systems that alert users through traditional visual, auditory or vibro-tactile feedbacks when posture requires attention. However, such notifications are disruptive and can be easily ignored. We address these issues with a new physiological feedback system that uses sensors to detect these poor postures, and electrical muscle stimulation to automatically correct the poor posture. We compare our automatic approach against other alternative feedback systems and through different unique contexts. We find that our approach outperformed alternative traditional feedback systems by being faster and more accurate while delivering an equally comfortable user experience.

Therapeutic Ocular Surface Medium (TOSM) is a potential new treatment for patients with ocular surface disorders such as dry eye and persistent epithelial defect (PED). New therapies are needed as many patients with dry eye and PED continue to suffer despite maximal standard therapy, and while efficacious autologous serum therapy is not routinely available. Like serum, TOSM contains tear components and was expected to have some of the physiological effects of tears. Clinical and in vitro studies were used to evaluate two similar formulations of TOSM. To comply with local pharmacy manufacturing policies, components were omitted from TOSM v1 to produce TOSM v2. In pilot studies, conducted over 1 month, TOSM v1 improved dry eye signs and symptoms and healed over a quarter of PED. In a 2 month randomised double-masked trial, TOSM v2 improved the signs and symptoms of dry eye but was not superior to saline (placebo). No serious or irreversible side-effects occurred. The altered composition of TOSM v2 may have reduced its efficacy. However, a significant improvement in blepharitis (eyelid margin disease) and conjunctival impression cytology (an objective measure of ocular surface health) was found with TOSM v2. Improvement in blepharitis is an encouraging finding as it has not been reported in other dry eye trials. It was hypothesised that TOSM would benefit ocular surface disorders by improving ocular surface health. In vitro, primary and cell line human corneal epithelial cells were supported by TOSM v1 and TOSM v2. Outgrowth from limbal explants and corneal reepithelialisation following wounding occurred with TOSM v2. This and the impression cytology findings support our hypothesis. Further, ocular surface damage with dry eye and PED may activate the corneal wound healing response. For wound healing, compared to human serum, TOSM v1 and TOSM v2 had beneficial effects in vitro on epithelial cells and human corneal fibroblasts. This may translate into a reduction in potentially vision-threatening corneal scarring in vivo with TOSM. However, ocular surface disorders are a heterogenous group and wound healing is a complex process such that different preparations of TOSM may be needed for use in different disorders and at different stages of the disease process.

Therapeutic Ocular Surface Medium (TOSM) is a potential new treatment for patients with ocular surface disorders such as dry eye and persistent epithelial defect (PED). New therapies are needed as many patients with dry eye and PED continue to suffer despite maximal standard therapy, and while efficacious autologous serum therapy is not routinely available. Like serum, TOSM contains tear components and was expected to have some of the physiological effects of tears. Clinical and in vitro studies were used to evaluate two similar formulations of TOSM. To comply with local pharmacy manufacturing policies, components were omitted from TOSM v1 to produce TOSM v2. In pilot studies, conducted over 1 month, TOSM v1 improved dry eye signs and symptoms and healed over a quarter of PED. In a 2 month randomised double-masked trial, TOSM v2 improved the signs and symptoms of dry eye but was not superior to saline (placebo). No serious or irreversible side-effects occurred. The altered composition of TOSM v2 may have reduced its efficacy. However, a significant improvement in blepharitis (eyelid margin disease) and conjunctival impression cytology (an objective measure of ocular surface health) was found with TOSM v2. Improvement in blepharitis is an encouraging finding as it has not been reported in other dry eye trials. It was hypothesised that TOSM would benefit ocular surface disorders by improving ocular surface health. In vitro, primary and cell line human corneal epithelial cells were supported by TOSM v1 and TOSM v2. Outgrowth from limbal explants and corneal reepithelialisation following wounding occurred with TOSM v2. This and the impression cytology findings support our hypothesis. Further, ocular surface damage with dry eye and PED may activate the corneal wound healing response. For wound healing, compared to human serum, TOSM v1 and TOSM v2 had beneficial effects in vitro on epithelial cells and human corneal fibroblasts. This may translate into a reduction in potentially vision-threatening corneal scarring in vivo with TOSM. However, ocular surface disorders are a heterogenous group and wound healing is a complex process such that different preparations of TOSM may be needed for use in different disorders and at different stages of the disease process.

Therapeutic Ocular Surface Medium (TOSM) is a potential new treatment for patients with ocular surface disorders such as dry eye and persistent epithelial defect (PED). New therapies are needed as many patients with dry eye and PED continue to suffer despite maximal standard therapy, and while efficacious autologous serum therapy is not routinely available. Like serum, TOSM contains tear components and was expected to have some of the physiological effects of tears. Clinical and in vitro studies were used to evaluate two similar formulations of TOSM. To comply with local pharmacy manufacturing policies, components were omitted from TOSM v1 to produce TOSM v2. In pilot studies, conducted over 1 month, TOSM v1 improved dry eye signs and symptoms and healed over a quarter of PED. In a 2 month randomised double-masked trial, TOSM v2 improved the signs and symptoms of dry eye but was not superior to saline (placebo). No serious or irreversible side-effects occurred. The altered composition of TOSM v2 may have reduced its efficacy. However, a significant improvement in blepharitis (eyelid margin disease) and conjunctival impression cytology (an objective measure of ocular surface health) was found with TOSM v2. Improvement in blepharitis is an encouraging finding as it has not been reported in other dry eye trials. It was hypothesised that TOSM would benefit ocular surface disorders by improving ocular surface health. In vitro, primary and cell line human corneal epithelial cells were supported by TOSM v1 and TOSM v2. Outgrowth from limbal explants and corneal reepithelialisation following wounding occurred with TOSM v2. This and the impression cytology findings support our hypothesis. Further, ocular surface damage with dry eye and PED may activate the corneal wound healing response. For wound healing, compared to human serum, TOSM v1 and TOSM v2 had beneficial effects in vitro on epithelial cells and human corneal fibroblasts. This may translate into a reduction in potentially vision-threatening corneal scarring in vivo with TOSM. However, ocular surface disorders are a heterogenous group and wound healing is a complex process such that different preparations of TOSM may be needed for use in different disorders and at different stages of the disease process.

No description available.

No description available.

Contrast sensitivity to vertically oriented grating patterns with a sinusoidal luminance profile were examined between groups of observers varying either in gender or age. For each observer at each of the seven spatial frequencies tested (.75, 1.5, 3, 6, 7.5, 10, 15 cyc/deg) threshold values were calculated for either ascending or descending trials as well as a combination of both. These threshold values were numerically transformed into sensitivity values and contributed to a group mean contrast sensitivity score for each spatial frequency. No significant effect of gender was found but younger observers (mean age=22.6 yrs.) exhibited significantly better contrast sensitivity than the older aged group (mean age=66.2 yrs.) for ascending trials at 3, 1.5 and .75 cyc/deg--the lowest spatial frequencies tested. Contrast sensitivity was also correlated with various measures. These findings were discussed in relation to the existing literature on age and spatial contrast sensitivity and since the machine used to examine the contrast sensitivity function (CSF) in this study utilized a laser interferometric method of stimulus generation, possible neurological changes with aging to explain this noted loss were also considered. Also discussed were various parameters that effect the CSF with a view toward explaining the disparate findings of various existing studies of age and the CSF. / Arts, Faculty of / Psychology, Department of / Graduate

Interprofessional education has the potential to prepare health career students to be practice-ready and enter the workforce with a collaborative mindset. Respiratory care educators must adequately prepare students to work in this capacity. This emphasis on a team approach to patient-centered care has the ability to impact and improve health outcomes. Throughout the last decade, sleep medicine has experienced fluctuations. Sustainability of sleep labs who only perform diagnostic testing may prove challenging. The role of interprofessional practice in sleep medicine would be to overcome traditional roles (silos) so that multiple skilled practitioners could help identify and treat complex patient conditions. A review of the literature demonstrated how various providers can serve as active members of interprofessional health care teams. The opportunity to expand services and partner with other providers to detect, educate, and treat sleep disordered breathing could help laboratories endure and even thrive in the current health care system.

Lung tumors secrete multiple factors that contribute to cachexia, a severe wasting syndrome that includes loss of muscle mass, weakness, and fatigue. 80% of advanced lung cancer patients experience cachexia, which cannot be reversed by nutritional interventions, diminishes response to and tolerance of cancer treatments, and increases morbidity and mortality. Despite a multitude of clinical trials, there are currently no approved treatments. This deficiency suggests that not all of the factors that contribute to cachexia have been identified. Cancer is frequently accompanied by an increase in cyclooxygenase-2 (COX-2), a hallmark of inflammation. Clinical trials for COX-2 inhibitors have resulted in restoration of muscle mass and decreased fatigue. Along with loss of myofibrillar proteins, cachexia also induces mitochondrial dysfunction, which contributes to fatigue. The amelioration of fatigue by COX-2 inhibition suggests possible alterations to mitochondrial function. We hypothesized that there were unidentified tumor-derived factors that contribute to cachectic wasting and fatigue. Treatment of C2C12 myotubes with Lewis lung cancer-conditioned media (LCM) resulted in increased COX-2 content, myosin loss, and mitochondrial dysfunction. Mass spectrometry revealed 158 confirmed proteins in LCM. We focused on extracellular 14-3-3 proteins because they bind and regulate over 200 known partners. We found that depletion of extracellular 14-3-3 proteins diminished myosin content. CD13, an aminopeptidase, is the proposed receptor for 14-3-3 proteins. Inhibiting aminopeptidases with Bestatin also reduced myosin content. LCM treatment decreased basal and ATP-related mitochondrial respiration, caused a transient rise in reactive oxygen species (ROS), and increased 4-Hydroxynonenal (4-HNE) in both cytosolic and mitochondrial fractions of cell lysates. COX-2 inhibition did not spare myosin content in LCM-treated myotubes, but did alter mitochondrial respiration and cytosolic oxidant levels. Our novel findings show that extracellular 14-3-3 proteins may act as previously unidentified myokines, signaling via aminopeptidases to help maintain muscle mass. We elucidated how LCM alters mitochondrial electron flow, and increases oxidative damage by ROS and 4-HNE. Although successful in clinical trials, COX-2 inhibitors do not appear to spare muscle mass by directly working on skeletal muscle, but did alter mitochondrial function.