A number of aspects of speech training involve assessing the quality of the student's speech. It is of interest to determine whether such speech quality analysis can be done automatically. This thesis provides a preliminary answer to that question by proposing and then evaluating a set of quality measures for comparing the quality of two segments of speech. Speech quality is taken to be the lack of defects in the articulatory and prosodic components of speech. It is a non-quantitative definition from speech pathology that can meet the needs of speech training. Speech defects common among deaf children and students of English as a second language are reviewed, and classified according to this scheme. The speech quality measures are based on a linear prediction model of speech, and adapt several techniques from the field of speech recognition. Evaluations using speech with known quality defects show that the articulatory measures are effective in detecting most of the common errors of articulation, with the exception of ones between nasal sounds. The prosodic quality measures of loudness and timing give very useful indications of syllable stress and voicing errors. The timing measure is derived from the optimal time-warping curve between the two utterances, and provides an accurate means of tracking speed variations in speech. Differences between speakers tend to mask articulatory quality errors, but have little effect on the prosodic quality measures. An articulatory distance measure is proposed that partly counters these interspeaker differences. Work remains to be done in a number of key areas, but the results of this preliminary investigation suggest that automatic speech quality analysis by computer is practical and may one day become a versatile tool for speech training. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Unknown

M.Tech. / Photodynamic therapy is a treatment that is used for the destruction of certain types of tumours and is emerging as a promising treatment modality in the field of dermatology (Davids et al., 2008). The photochemical interactions of the photosensitizer, light and molecular oxygen producing reactive oxygen species known as ROS, results in damage to organelles within malignant cells and so can lead to tumour destruction (Plaetzer et al., 2008). Melanoma is one of the most common forms of malignancies (Oliveria et al., 2007). Unfortunately, there are limited treatment options available for this disease because chemotherapy and radiation therapy are largely ineffective. Metastatic disease frequently develops even after potentially curative surgery (MacCormack, 2008). Since this metastatic disease is an understudied cancer, and the incidence and mortality is increasing, describing the long term burden of this cancer and identifying factors that contribute to it will facilitate efforts to develop responsive prevention strategies, so that novel therapies such as PDT can be proposed (Oliveria et al., 2007; Pan et al., 2008; Schuitmaker et al., 1996). Numerous worldwide clinical trials have shown that PDT represents an effective and safe modality for various skin disorders, but little research has been done in terms of its effect on malignant melanomas (De Rosa and Bentley, 2000; Kolarova et al., 2008). In order for PDT to be an effective treatment modality it depends on many factors such as the type of photosensitizer utilized its ability to selectively penetrate tumour cells and the duration of the treatment (Robertson et al., 2009). Other important factors include the type of activating light source, its ability to penetrate the desired target and the duration of exposure (Plaetzer et al., 2008). Lastly, the type of target cells and their oxygen status also play an important role in the efficacy iv of PDT (Kolarova et al., 2008). In order for PDT to be completely effective, the resulting damage from the treatment must surpass cellular repair mechanisms and cause direct destruction of cellular pathways through vascular compromise and increase immune response to overcome disease (Pazos and Nader, 2007). Porphyrins are the most studied photosensitizers and their disadvantage is the inability to specifically localize in tumour cells and so they are retained in normal cells for prolonged periods, causing patients to be photosensitive (Braathen et al., 2007). This factor stimulated the development of second generation photosensitizers with improved physical, chemical and spectral properties (Davids et al., 2008). Phthalocyanine compounds are second generation photosensitizers which have shown potential in the PDT treatment of many cancers (Kolarova et al., 2007).

This dissertation describes the development of the Victoria Symptom Validity Test (VSVT). The VSVT was designed to assist in screening for non-optimal performance during neuropsychological evaluation due to malingering, psychiatric disturbance, or other environmental or dispositional factors. Specifically, the VSVT is a test of recognition memory that uses the forced-choice paradigm for detecting biased or random responding. Response latency is also recorded. Results from pilot and follow-up normative studies with experimental and clinical populations are presented. The VSVT was found to have excellent divergent and adequate convergent validity in samples of compensation-seeking and noncompensation-seeking patients. Classifications of experimental participants using below chance performance as a cutoff were consistent with the majority of previous studies in finding 100% specificity but poor sensitivity. A new system wherein a third category is added for questionable (at chance) performance showed greatly increased sensitivity, with no decrement in specificity. Although scores in the questionable range are not unequivocal indicators of malingering, findings suggest good utility for screening or corroborative purposes. A Bayesian diagnostic probability matrix that takes base-rates into account was also provided as a more flexible alternative to absolute cutoff scores. Response latency as a measure of symptom validity was shown to have adequate sensitivity for screening, but less acceptable discriminant validity and lower specificity. Limitations of experimental results and clinical applications of symptom validity tests are discussed. / Graduate

A rapid, objective indicator of pyogemc infection would be of great value in the practice of clinical medicine. On the basis of earlier studies it was claimed that the nitroblue tetrazolium ( NBT) test might fulfill such a role. In view of the potential value of this test, it was reassessed m order to determine its diagnostic accuracy and clinical value. The results obtained in this study did not conform with those previously published. Elevated NBT scores were not diagnostic of pyogenic infection, there was a wide overlap of the results of tests performed on patients with pyogenic disease, patients with other diseases and normal subjects. In addition, there was a significant observer error in the interpretation of the slide preparations. The extent of this error was reduced with experience, but was still considerable in the hands of experienced observers. In the NBT test, the dye enters neutrophils by phagocytosis of NBT in particulate form, complexed to heparin and/or '·fibrinogen. The proportion of neutrophils which phagocytose these complexes seems to be related to the severity of illness of the patient. As serum from these patients is capable of enhancing phagocytosis of complexed dye by normal cells, a humeral factor could be responsible for the increased phagocytosis of complexed NBT indicated by a positive test. , Of the compounds tested, man m vitro model system designed to simulate the NBT test, 3 a,l_acid glycoprotein, immunoglobulins and endotoxin, in concentrations that occur in vivo, enhanced NBT reduction. Any one of these compounds, singly or in combination, could be responsible for positive NBT tests.

Prostate cancer (PCa) is one of the most common cancer in men and affecting hundreds of thousands of men worldwide. The early detection of PCa have been proven to be advantageous for more efficient treatment against PCa. However, the conventional screening methods towards PCa are lack of selectivity and sensitivity, which leading to high false positive rate and overdiagnosis of PCa. The objective of this study is to (1) identify more sensitive and accurate diagnostic biomarkers towards PCa; (2) followed by developing new chemosensor towards the newly found biomarkers. In the first part of this study, based on the previously findings on urinary spermine as useful biomarker for PCa, a more comprehensive study on urinary polyamine levels was carried out and the important role of urinary spermine as biomarker for PCa detection was consolidated. In the second part of this work, molecularly imprinted polymer (MIP) towards the target analyte of urinary spermine was prepared for the capturing and extraction of spermine. The specific adsorption and selectivity towards spermine of the MIP were discussed and reported. In the third part of this study, a rapid detection method of spermine was developed via the use of aggregation-induced emission (AIE) active molecules. The presence of spermine would cause aggregation of this chemosensor for a "turn-on" detection of spermine under ultra-violet (UV) excitation, which would be useful in PCa diagnosis in the future.

No description available.

A method of trace element analysis using proton-induced X-ray emission (PIXE) techniques with energy dispersive X-ray detection methods is described. Data were processed using the computer program ANALEX. PIXE analysis methods were applied to the analysis of liver, spleen, aorta, kidney medulla, kidney cortex, abdominal fat, pancreas and hair from autopsies of Pima Indians. Tissues were freeze dried and low temperature ashed before analysis. Concentrations were tabulated for K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Pb, Se, Br, Rb, Sr, Cd and Cs and examined for significant differences related to diabetes. Concentrations of Ca and Sr in aorta, Fe and Rb in spleen and Mn in liver had different patterns in diabetics than in nondiabetics. High Cs concentrations were also observed in the kidneys of two subjects who died of renal disorders. Analyses by atomic absorption and PIXE methods were compared. PIXE methods were also applied to elemental analysis of obsidian artifacts from Campeche, Mexico. Based on K, Ba, Mn, Fe, Rb, Sr and Zr concentrations, the artifacts were related to several Guatemalan sources.

The fact therefore remains that, at the present time, Crohn's disease is still an enigma. The aetiology and pathogenesis are obscure, the clinical findings and progression of the disease are unpredictable and the histological findings are often nonspecific. With this in mind, this dissertation attempts to define and document the incidence of certain histological features at presentation in a population of Crohn's disease patients from Groote Schuur Hospital. The main aim is to determine the incidence of granulomas in the study group as a whole, as well as to establish the distribution of granulomas within the bowel. A correlation between the presence of granulomas and the clinical activity of the disease (as assessed by the Crohn's Disease Activity Index) is also sought.

Thesis (M.Sc. (Med.) (Emergency Medicine))--University of the Witwatersrand, Faculty of Health Sciences, 2014. / INTRODUCTION Cardiac injury following blunt chest trauma (BCT) presents a clinical spectrum of varying severity ranging from asymptomatic to severe and life-threatening. Attempts to diagnose acute cardiac injury may lead to unnecessary investigations and hospitalisation. Conversely, those patients “not at risk” could potentially be discharged from hospital. This research reviewed what methods are utilised by doctors to identify those patients at risk of acute cardiac injury. METHODS An on-line questionnaire was mailed to doctors working in emergency departments (EDs) throughout South Africa to ascertain what history, examination, and special investigations should be performed on patients presenting with blunt chest injury to exclude cardiac injury. RESULTS These revealed varied responses with inappropriate investigations and lacked unanimity in the diagnostic methods. The majority of doctors did not adhere to up-to-date consensus driven and evidenced based up-to-date practice There was not much difference in the respondents responses between specialist emergency physicians (SEPs) and general practitioners (GPs). CONCLUSION A high index of suspicion based on careful history taking and physical examination together with specific diagnostic testing limited to identifying those patients at risk of a cardiac injury (and developing cardiac complications) presenting with BCT should be the cornerstone of this diagnostic challenge. It was evident that the diagnosis of acute cardiac injury remains an elusive challenge and lacks consistent utilisation of diagnostic criteria.

Headache is a common complaint in society and is related to personal, biomechanical and socioeconomic circumstances. In current literature trigger-points (TrPs) in the majority of the muscles of the face and neck contributing to tension-type headache (TTH) have been evaluated, except the TrPs of the masseter muscles. The aim of this studyis to determine the association between myofascial (TrPs) in the masseter muscle group and episodic tension-type headache (ETTH). Fourteen subjects with ETTH were matched with same sex and same age subjects not suffering from headache acting as the control group. The diagnostic criteria as described by Simons and Travel (1999) were used in the objective tests to diagnose the TrPs in the masseter muscles. Subjective tests included a disability questionnaire, National stress awareness day stress questionnaire, (NSAD stress questionnaire), a precipitating and aggravating factors questionnaire. Active TrPs were found in 92.86% of ETTH group and 7.14% had latent TrPs. Within the control group 7.14% had active TrPs, 14.29% latent TrPs and 78.37% had no TrPs.Differences in the presence of masseter TrPs between the ETTH and control group were significant with p-value <0.001. All the questions asked in the headache disability questionnaire evaluating headache frequency, intensity and severity were significantwith p-value<0.005. The NSAD stress questionnaire revealed statistical significant values for questions pertaining to muscular aches and pains and subjectively subjects claimed that theyfelt tension at work. The precipitating questionnaire showed that physical activity, stress / tension and reading were significant precipitating factors for developing a tension-type headache. The aggravating questionnaire only showed light as an aggravating factor. Stress and tension had 100% “yes”answers in the ETTH group.Weather as an aggravating factor had 100% “no” answersfrom the control group.Physical activity, driving and noise had relative high percentages of “yes”answers from the ETTH group and higher probability scores for being an aggravating factor whencomparing the ETTH and control group, but were not found to be statistically significant. Myofascial TrPs in the masseter muscle group contribute to the origin and or maintenance of ETTH.