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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

The determinants of sexually transmitted and blood borne infection risk among incarcerated youth

Kinasevych, Bohdanna 13 April 2011 (has links)
The purpose of this study is to describe the determinants of STBBI related knowledge, risk behaviours, and prevalence as they relate to sexual health among incarcerated youth between 16 and 24 years of age in Manitoba. The study involved a cross-sectional questionnaire and testing for chlamydia, gonorrhea, syphilis, HIV, and Hepatitis C among 210 male and female youth in nine provincial correctional centres. Descriptive analysis of STBBI knowledge, risk behaviours, and prevalence are presented. Potential associations between each of these sexual health outcomes and the epidemiologic context of risk are explored using univariate and multiple regression analysis. Longer incarceration history was associated with higher STBBI knowledge, higher sexual risk behaviours and higher STBBI prevalence. STBBI knowledge was associated with growing up on a reserve. Early age of initial substance use and injection drug use were found to be significantly associated with poor sexual health. Recommendations include increasing STBBI awareness using culturally appropriate, peer-led interventions, improving educational attainment, integrating sexual health education with substance use interventions inside corrections, increasing collaboration between community and corrections and improving opportunities for STBBI screening inside correctional centres.
82

Acoustic and Perceptual Evaluation of the Quality of Radio-Transmitted Speech

Kirtikar, Shantanu Sanatkumar January 2010 (has links)
Aim When speech signals are transmitted via radio, the process of transmission may add noise to the signal of interest. This study aims to examine the effect of radio transmission on the quality of speech signals transmitted using a combined acoustic and perceptual approach. Method A standard acoustic recording of the Phonetically Balanced Kindergarten (PBK) word list read by a male speaker was played back in three conditions, one without radio transmission and two with two types of radio transmission. The vowel segments (/i, a, o, u/) embedded in the original and the re-recorded signals were analysed to yield measures of frequency loci of the first two formant frequencies (F1 and F2), amplitude difference between the first two harmonics (H1-H2), and singing power ratio (SPR). Other measures included Spectral Moment One (mean), Spectral Moment Two (variance), and the energy ratio between consonant and vowel (CV energy ratio). To examine how H1-H2 and SPR were related to the perception of vowel intelligibility and clarity, vowels at five levels of each of these two measures were selected as stimuli in the perceptual study. The auditory stimuli were presented to 20 normal hearing listeners, including 10 males and 10 females aged between 21 to 42 years, the listeners were asked to identify the vowel for each vowel stimulus in the vowel identification task and judge from a contrast pair which vowel sounded “clearer” in the clarity discrimination task. A follow-up study using vowel stimuli with a constant length and five H1-H2 or five SPR levels was conducted on five listeners to determine the relationship between the perception of speech clarity and H1-H2 or SPR. Results Results from a series of one-way or two-way analyses of variance (ANOVAs) or ANOVAs on Ranks and post-hoc test revealed that radio transmission had a significant effect on all of the selected acoustic measures except for the CV energy ratio. Signal degeneration due to radio transmission is characterized by changes of F1 or F2 frequencies toward a more compressed vowel space, a H1-H2 value indicating an increase of H1 dominance, a SPR value suggestive of an increase in the energy around the 2-4 kHz region, and a loss of differentiation between /s/ and /sh/ on the measures of Spectral Moments One and Two. Vowel duration was also found to play a major role in affecting the perception of vowel intelligibility and clarity. The follow-up study, with a control on vowel duration, found that SPR played a role in affecting the perception of vowel intelligibility and clarity. Conclusion It was concluded from the findings that measures of energy ratio between different frequency regions, as well as the frequencies of the first two formant frequencies, were sensitive in detecting the effect of radio transmission.
83

The determinants of sexually transmitted and blood borne infection risk among incarcerated youth

Kinasevych, Bohdanna 13 April 2011 (has links)
The purpose of this study is to describe the determinants of STBBI related knowledge, risk behaviours, and prevalence as they relate to sexual health among incarcerated youth between 16 and 24 years of age in Manitoba. The study involved a cross-sectional questionnaire and testing for chlamydia, gonorrhea, syphilis, HIV, and Hepatitis C among 210 male and female youth in nine provincial correctional centres. Descriptive analysis of STBBI knowledge, risk behaviours, and prevalence are presented. Potential associations between each of these sexual health outcomes and the epidemiologic context of risk are explored using univariate and multiple regression analysis. Longer incarceration history was associated with higher STBBI knowledge, higher sexual risk behaviours and higher STBBI prevalence. STBBI knowledge was associated with growing up on a reserve. Early age of initial substance use and injection drug use were found to be significantly associated with poor sexual health. Recommendations include increasing STBBI awareness using culturally appropriate, peer-led interventions, improving educational attainment, integrating sexual health education with substance use interventions inside corrections, increasing collaboration between community and corrections and improving opportunities for STBBI screening inside correctional centres.
84

Simulation of the transmitted dose in an EPID using a Monte Carlo method.

Pham, Thuc M. January 2009 (has links)
The BEAMnrc and DOSXYZnrc codes from EGSnrc Monte Carlo (MC) system are considered to be the gold standards for simulating radiotherapy linear accelerators and resulting dose depositions (Rogers, Faddegon et al. 1995). The aim of this project was to setup the EGSnrc system for the simulation of the linear accelerator (linac) head and a Scanning Liquid Ionisation Chamber (SLIC) Electronic Portal Imaging Device (EPID) for calculations of transmitted dose in the EPID. The project was divided into two parts. The head of a 6 MV Varian 600C/D photon linac was first simulated by BEAMnrc. The modelling parameters such as the electron beam energy and the Full Width at Half Maximum (FWHM) of the electron spatial distribution were adjusted until the absorbed dose profiles and the Percentage Depth Dose (PDD) curves, in general agreed better than the measured profiles and PDDs by 2%. The X-ray beam obtained from the modelled linac head was used for the simulation of the transmitted dose in the EPID in the second part of the project. The EPID was simulated by DOSXYZnrc based on the information obtained from Spezi and Lewis 2002 (Spezi and Lewis 2002), who also modelled the Varian SLIC EPID (MK2 Portal Vision system, Varian Inc., Palo Alto, CA, USA). The comparisons between the measured and the simulated transmitted doses were carried out for three different phantom setups consisting of an open field, homogeneous water equivalent phantom and a humanoid phantom (RANDO). These phantom setups were designed so that the accuracy of the MC method for simulating absorbed dose in air, homogeneous and inhomogeneous phantoms could be assessed. In addition, the simulated transmitted dose in an EPID was also compared with values obtained from the Pinnacle treatment planning system (v6.2b, Phillips Medical Systems). In the process of selecting the electron beam energy and FWHM, it was confirmed (Sheikh-Bagheri and Rogers 2002; Keall, Siebers et al. 2003) that the variation of the electron beam FWHM and energy influenced the beam profiles strongly. The PDD was influenced by the electron beam energy less strongly. The increase in the energy led to the increase in the depth of maximum dose. However, the effect could not be observed until the energy change of 0.2 MeV was made. Based on the analysis of the results, it was found that the combination of FWHM and energy of 1.3 mm and 5.7 MeV provided the best match between the measured and MC simulated beam profiles and PDDs. It can be concluded that an accuracy of 1.5% can be achieved in the simulation of the linac head using Monte Carlo method. In the comparison between the Monte Carlo and the measured transmitted dose maps, agreements of 2% were found for both the open field and homogeneous water equivalent phantom setups. The same agreements were also found for the comparison between Monte Carlo and Pinnacle transmitted dose maps for these setups. In the setup where the humanoid phantom RANDO was introduced in between the radiation field and the EPID, a general agreement of about 5% found for the comparison between Monte Carlo and measured transmitted dose maps. Pinnacle and measured transmitted dose map was also compared for this setup and the same agreement was found. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1352973 / Thesis (M.Sc.) - University of Adelaide, School of Chemistry and Physics, 2009
85

HIV/STD Prevention in General Practice

Proude, Elizabeth Marjorie January 2002 (has links)
This thesis examines aspects of the prevention of sexually transmitted diseases (STDs) in the Australian community, with a particular emphasis on HIV/AIDS in the context of general practice (or primary care settings). The work has four broad aims: i) To describe the primary prevention of sexually transmitted diseases, following from the arrival of the HIV/AIDS pandemic in Australia ii) To describe HIV/STD risk behaviour iii) To summarise previously known evidence of interventions to reduce risk and to raise awareness of HIV and other sexually transmitted diseases iv) To contribute new evidence addressing the potential of the general practitioners' role in HIV/STD prevention The first chapter gives a brief review of the history of HIV/AIDS from its discovery in the United States of America to its appearance in Australia and New Zealand, and discusses the Australian response strategies, both initial and continuing, to confine the epidemic. Specifically, the arrival of HIV/AIDS gave rise to increasing awareness of sexually transmitted diseases, which hitherto, although sometimes chronic, were rarely fatal. The public health risk of HIV necessitated swift government action and led to wider acceptance of publicity about sexual behaviour. Although the thesis does not concentrate solely on HIV, this is still an emphasis. This chapter provides useful background to ensuing chapters. Chapter Two provides an overview of behavioural risk in sexually transmitted diseases. It gives a review of risk factor prevalence studies, and introduces risk behaviour and cognitive models of behaviour change, as applied to STD risk. Sexual behaviour is a complex social interaction, usually involving more than one person, and relying on the personality and behaviour patterns intrinsic to the individuals taking part. It is therefore perhaps more challenging to alter than behaviour which is undertaken alone, being dependent on the behaviour and intentions of both parties. Moreover, comprehensive assessment of sexual risk behaviour requires very detailed information about each incident. Its private nature makes accurate data difficult to obtain, and sexual risk behaviour is, correspondingly, difficult to measure. Chapter Three reviews the effectiveness of interventions tested in primary health care settings to reduce sexual risk behaviour. The candidate uses a replicable method to retrieve and critique studies, comparable with standards now required by the Cochrane Collaboration. From 22 studies discussed, nine health interventions were short, 'one-shot', efforts owing to limited time, resources and other practical constraints. This review demonstrates the scarcity of interventions with people who may be perceived as 'low-risk'. Only four interventions were carried out in community health centres and two in university health clinics. One of the university interventions showed no change in sexual behaviour in any of three arms of the intervention (Wenger, Greenberg et al 1992) while the other showed an increase in condom use in both groups, although the intervention group's self-efficacy and assertiveness also improved (Sikkema, Winett & Lombard 1995). The rationale for the intervention, where given, is described. Chapter Four analyses the content, format and quality of sexual health information brochures available in New South Wales at the time of the candidate's own planning for an interventional study. One of the most effective ways to disseminate information widely is by the use of educational literature, especially when the subject material is potentially sensitive or embarrassing to discuss in person. In this chapter, the candidate reviews the literature available at the time of designing the intervention used in Chapter Five. Readability, attractiveness, clarity and the accurate presentation of facts about sexually transmitted disease risk are examined for each pamphlet. Forty-seven pamphlets were scored according to the Flesch formula, and twenty-four of these scored in the 'fairly' to 'very difficult' range. There was, therefore, a paucity of easy-to-read material on these subjects. Chapter Five evaluates a general practitioner-based counselling intervention to raise awareness of sexually transmitted diseases and to modify HIV/STD risk behaviour. While adults aged 18-25 are less likely than older cohorts to have a regular general practitioner or to visit often, most people visit a general practitioner at least once a year. This could provide an opportunity for the general practitioner to raise preventive health issues, especially with infrequent attendees. As the effectiveness of an opportunistic intervention about sexual risk behaviour was yet to be tested, the candidate designed an innovative randomised controlled trial to raise awareness of risk and increase preventive behaviour. The participation rate was 90% and 76% consented to followup; however the attrition rate meant that overall only 52% of the original participants completed the follow-up questionnaire. The intervention proved easy and acceptable both to GPs and to patients, and risk perception had increased at three months' follow-up; however this occurred in both the control (odds ratio 2.6) and the intervention group, whose risk perception at baseline was higher (odds ratio 1.3). In order to establish some markers of risk in the general population, Chapter Six analyses data resulting from questions on sexual behaviour asked in the Central Sydney section of the NSW Health Survey. The candidate advocated for inclusion of relevant questions to determine some benchmarks of sexual risk behaviour and to provide an indication of condom use among heterosexuals. Although limited in scope as a result of competing priorities for questions in the survey, results demonstrate that, while a small percentage of people were at risk, those with higher levels of partner change or of alcohol use were the most likely to always use condoms. Specifically, 100% of those with more than four new partners in the last 12 months had used condoms with every new partner. In addition, 'heavy' alcohol users were more likely to report condom use every time with new partners (odds ratio 0.34). To furnish data to inform future planning of educational activities for general practitioners, Chapter Seven presents the results of a survey of Central Sydney general practitioners' opinions and current practices in HIV risk reduction with in the broader context of sexually transmitted disease prevention. The general practitioner is in an ideal position to provide information and advice, especially if future research affirms the impact of such advice on STD risk behaviour. General practitioners in this study said they would be slightly more likely to discuss sexual health matters with young patients than with older ones (p=0.091), but this was not significant. The most cited barrier to discussing sexual health was inadequate remuneration for taking time to do so (over 50% gave this reason). The next most cited obstacle was difficulty in raising the subject of STDs or HIV in routine consultations, but this reason was given by less than half the sample. Forty-six percent had participated in continuing medical education programs in STDs, HIV/AIDS, or hepatitis diagnosis or management; 32% of GPs had patients with HIV, and 55% of all GPs indicated they would like more training in management and continuity of care of HIV patients. Approximately half (51%) wanted more training in sexuality issues, including sexual dysfunction. Chapter Eight reviews the whole thesis and discusses future directions for the research agenda.
86

n vitro anti-HIV-1 properties of ethnobotanically selected South African plants used in the treatment of sexually transmitted diseases

Tshikalange, Thilivhali Emmanuel. January 2007 (has links)
Thesis (PhD (Medical Plant Science)--University of Pretoria, 2007. / Summary in English. Includes bibliographical references. Available on the Internet via the World Wide Web.
87

Antimicrobial and spermicidal activity of hydrogen peroxide and nonoxynol-9 based gel preparations

Grimmett, Paul E. January 2004 (has links)
Thesis (M.S.)--Marshall University, 2004. / Title from document title page. Document formatted into pages; contains x, 67 p. Includes abstract. Includes bibliographical references (p. 48-50).
88

Sexual risk behaviours of travellers in Hong Kong work population

Chan, Kwok-hung, January 2003 (has links)
Thesis (M.Med.Sc.)--University of Hong Kong, 2003. / Includes bibliographical references (leaves 56-62). Also available in print.
89

Myths and misconceptions exploring beliefs about pregnancy and sexually transmitted diseases in adolescents /

Robertus, Kacie Taylor. January 2010 (has links) (PDF)
Professional paper (M Nursing)--Montana State University--Bozeman, 2010. / Typescript. Chairperson, Graduate Committee: Barbara Derwinski-Robinson. Includes bibliographical references (leaves 38-43).
90

Communication patterns following the acquisition of a sexually transmitted infection

Fletcher, Courtney Vail. January 2005 (has links)
Thesis (M.A.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains vi, 89 p. Includes abstract. Includes bibliographical references (p. 62-74).

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