What obese and non-insulin dependent diabetes mellitus patients experience and expect from their primary care doctors concerning weight-loss management

M.Fam.Med. Faculty of Health Sciences, University of the Witwatersrand, 2009.Worldwide, obesity prevalence is rapidly rising. Doctors have poor understanding of what patients experience and expect from them regarding weight-loss management. This qualitative study explored what obese patients with Non-insulin Dependent Diabetes Mellitus experience and expect from their primary care doctors concerning weight-loss management. Free attitude interviews were conducted with eight participating patients. The findings showed that doctors encouraged and counselled patients regarding weight-loss, mainly giving dietary advice, but did not routinely weigh them. Patients accepted responsibility for losing weight, trusted their doctors, valued their advice highly and did not want referrals to gymnasiums or dieticians. They expected doctors to advise them practically about exercise, diet and weight-loss goals, weigh them regularly and communicate effectively. They believed that doctor-patient relationships and interaction are important in weight-loss management, patients should be treated on an individual basis and the process should be empowering. Medical intervention costs were not problematic for this group. Generally patients were satisfied with their doctors but there were areas concerning patients’ expectations that primary care doctors should take cognisance of

Paediatric dental chair sedation: a Gauteng-based pilot study

BACKGROUND: Procedural sedation and analgesia (PSA) is generally safe, and often necessary to successfully undertake dental procedures in children. Providing PSA in dental rooms avoids expenses generated by having to perform procedures in operating theatres, but this must not be done at the cost of patient safety. Although rare, severe adverse events that occur are usually preventable. Death and permanent neurological injury are unacceptable outcomes for healthy children being sedated for minor procedures. OBJECTIVES: The objectives of this study were to determine the proportion of dental practitioners making use of paediatric dental chair PSA in Gauteng, describe their PSA practice, and to determine adherence to recommended safety standards

Application of Spatial Statistics in Transportation Engineering

“Everything is related to everything else, but near things are more related than distant things” is the first law of geography. It can be hypothesized that spatially, occurrence of a crash can exhibit similarities. To identify spatial patterns of crashes, this chapter presents spatial autocorrelation techniques such as Moran’s I and the Getis-Ord Gi*statistics; spatial interpolation such as kriging; and nonparametric probability density function and kernel density (K). The aim of this chapter is to provide application of spatial statistics in transportation engineering specifically to identify crash concentrations and patterns of clusters in a study area

Unaltered perception of suprathreshold contrast in early glaucoma despite sensitivity loss

YesPURPOSE. Glaucoma raises contrast detection thresholds, but our natural visual environment is dominated by high contrast that may remain suprathreshold in early to moderate glaucoma. This study investigates the effect of glaucoma on the apparent contrast of visible stimuli. METHODS. Twenty participants with glaucoma with partial visual field defects (mean age, 72 ± 7 years) and 20 age-similar healthy controls (mean age, 70 ± 7 years) took part. Contrast detection thresholds for Gabor stimuli (SD, 0.75°) of four spatial frequencies (0.5, 1.0, 2.0, and 4.0 c/deg) were first measured at 10° eccentricity, both within and outside of visual field defects for participants with glaucoma. Subsequently, the contrast of a central Gabor was matched to that of a peripheral Gabor with contrast fixed at two times or four times the detection threshold. Data were analyzed by linear mixed modelling. RESULTS. Compared with controls, detection thresholds for participants with glaucoma were raised by 0.05 ± 0.025 (Michelson units, ± SE; P = 0.12) and by 0.141 ± 0.026 (P < 0.001) outside and within visual field defects, respectively. For reference stimuli at two times the detection contrast, matched contrast ratios (matched/reference contrast) were 0.16 ± 0.039 (P < 0.001) higher outside compared with within visual field defects in participants with glaucoma. Matched contrast ratios within visual field defects were similar to controls (mean 0.033 ± 0.066 lower; P = 0.87). For reference stimuli at four times the detection contrast, matched contrast ratios were similar across all three groups (P = 0.58). Spatial frequency had a minimal effect on matched contrast ratios. CONCLUSIONS. Despite decreased contrast sensitivity, people with glaucoma perceive the contrast of visible suprathreshold stimuli similarly to healthy controls. These results suggest possible compensation for sensitivity loss in the visual system.Supported by a College of Optometrists PhD Scholarship.Research Development Fund Publication Prize Award winner, June 202

Acceleration Behavior of Drivers in a Platoon

A new dual-regime acceleration model was developed to represent the acceleration behavior of drivers in a platoon of vehicles. Two sets of field data collected by aerial photographic techniques were used to assess the validity of the proposed and existing acceleration models. A single regime acceleration model failed to present the acceleration behavior of drivers. The field data indicated that at around 13 m/sec the acceleration rate drops. Thus, two different acceleration rates, higher acceleration rate at lower speeds and lower acceleration rate at higher speeds, were used to provide the best fit to the data. This provided realistic acceleration behavior of drivers in a platoon. The field data sets were collected about 10 years apart. The improvements in acceleration capability of a platoon of vehicles from two different time periods were determined. Improvements in performance of vehicles were quantified using the above mentioned field data. The method of quantification can also be used to predict and model the performance of vehicles currently in use. Inversely, current vehicles can be downgraded to represent vehicles of past years and thus make use of already collected data. Important uses of the dual regime model are in modeling the traffic flow behavior and designing roadway elements that depend on acceleration behavior of drivers

Novel biomarker identification in pancreatic cancer using Raman spectroscopy

Pancreatic cancer presents an increasing mortality burden, with little improvement in survival rates since 1970, largely because of the non-resectable status of most tumours at diagnosis and high rate of recurrence after resection. Currently, there are significant problems with accurately identifying tumour margins, both during surgery and through histopathology, causing limitations in clinical practice and research. This presents a need for clinically applicable research, to improve detection and differentiation of healthy and cancerous tissue in the exocrine pancreas. SPARC has been shown to play a role and be expressed in the development of pancreatic cancer and has recently been identified as a potential biomarker for the disease. Raman spectroscopy is an emerging technology, showing promise in the detection and surgical guidance of many cancers. There is, however, limited research on its use in pancreatic cancer. This study aims to investigate the utility of Raman spectroscopy in identifying and exploring the development of pancreatic cancer and differences between healthy and cancerous pancreatic tissue, which could eventually allow translation to clinical practice. This study identifies differences between healthy and cancerous pancreatic tissue, using Raman spectroscopy in human tumour resections and blood samples. Differences are seen due to proline and nucleic acids in fresh tissue and collagen in fixed tissue. It further utilises a 2D cell-line model, Raman spectroscopy and ELISA, providing greater understanding of the interactions between cancer and stellate cells, including the production of SPARC and collagen, in pancreatic cancer. This study concludes by proposing a hypothesis, highlighting the importance of collagen, SPARC and their potential roles in causing biochemical changes to cancer cells and as possible biomarkers. Overall, it demonstrates the potential utility of Raman spectroscopy in pancreatic cancer, providing the basis for further research and translation to clinical practice, improving survival rates and reducing the mortality burden currently associated with the disease

Health professionals' perceptions of cultural influences on stroke experiences and rehabilitation in Kuwait

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2012 Informa UK Ltd.Purpose: The aim of this study was to investigate the perceptions of health professionals who treat stroke patients in Kuwait regarding cultural influences on the experience of stroke and rehabilitation in Kuwait. Health professionals interviewed were from a variety of cultural backgrounds thus providing an opportunity to investigate how they perceived the influence of culture on stroke recovery and rehabilitation in Kuwait. Method: Semi-structured interviews were carried out with 12 health professionals with current/recent stroke rehabilitation experience in Kuwait, followed by thematic analysis of the verbatim transcripts. Results: The health professionals identified several features of the Kuwaiti culture that they believed affected the experiences of stroke patients. These were religious beliefs, family involvement, limited education and public information about stroke, prevailing negative attitudes toward stroke, access to finances for private treatment, social stigma and the public invisibility of disabled people, difficulties identifying meaningful goals for rehabilitation, and an acceptance of dependency linked with the widespread presence of maids and other paid assistants in most Kuwaiti homes. Conclusion: To offer culturally sensitive care, these issues should be taken into account during the rehabilitation of Kuwaiti stroke patients in their home country and elsewhere

Suprathreshold Visual Function in Glaucoma

Glaucoma is the leading cause of irreversible blindness worldwide but the effect of glaucoma on patients’ vision under suprathreshold conditions relevant to their natural visual environment is poorly understood. This project aimed to investigate and further understand the effects of glaucoma on three aspects of suprathreshold vision; apparent contrast of suprathreshold stimuli, detection and discrimination of image blur and crowding of peripheral vision. Psychophysical methods were employed to assess these three visual functions by measuring contrast matches of Gabor stimuli, blur detection and discrimination thresholds of edge stimuli and crowding ratios of Vernier targets. These measures were obtained from glaucoma observers tested within and outside of visual field defects and the data compared with healthy controls. Contrast matching ratios were similar between glaucoma and healthy age similar controls despite sensitivity loss in the glaucoma group. Blur detection and discrimination thresholds were similar between glaucoma observers’ tested within and outside of visual field defects and age-similar controls, though thresholds were slightly elevated for high contrast stimuli in the glaucoma visual field defect group. Crowding ratios were similar between participants with glaucoma and healthy young controls. The results demonstrate that aspects of suprathreshold visual function can be maintained in early glaucoma despite sensitivity loss at threshold. The results provide empirical evidence as to the asymptomatic nature of the disease in its early stages. It appears that in early glaucoma, there may be compensatory mechanisms at work within the visual system under suprathreshold conditions that can overcome loss of sensitivity at threshold.The College of Optometrist

Effects of glaucoma on detection and discrimination of image blur

YesBlur is one of the most commonly reported visual symptoms of glaucoma, but it is not directly measured by current clinical tests. We aimed to investigate the effects of glaucoma on detection and discrimination of image blur. People with glaucoma, separated into two groups with (n=15) or without (n=17) central visual field defects measured by 10-2 perimetry, and an age-similar control group (n=18) participated. First, we measured contrast detection thresholds centrally using a 2-interval forced choice procedure. We then measured blur detection and discrimination thresholds for the same stimuli (reference blurs 0, 1 arcmin respectively) using a 2-alternative forced choice procedure under two contrast conditions; 4x individual detection threshold for the low contrast condition, 95% contrast for the high contrast condition. The stimulus was a horizontal edge bisecting a hard-edged circle of 4.5° diameter. Data were analysed by linear mixed modelling. Contrast detection thresholds for the glaucoma group with central visual field defects were raised by 0.014 ± 0.004 (mean ± SE, Michelson units) (p=0.002) and by 0.011 ± 0.004 (p=0.03) relative to control and glaucoma without central visual field defect groups respectively. Blur detection and discrimination thresholds were similar between groups, with small elevations in blur detection thresholds in the glaucoma groups not reaching statistical significance (detection p=0.29, discrimination p=0.91). The lower contrast level increased thresholds from the higher contrast level by 1.30 ± 0.10 arcmin (p<0.001) and 1.05 ± 0.096 arcmin (p<0.001) for blur detection and discrimination thresholds respectively. Early-moderate glaucoma resulted in only minimal elevations of blur detection thresholds that did not reach statistical significance in this study. Despite the prevalence of blur as a visual symptom of glaucoma, psychophysical measurements of blur detection or discrimination may not be good candidates for development as clinical tests for glaucomaCollege of Optometrists PhD scholarshi