Zugl.: Tübingen, Universiẗat, Diss., 1997.

Braunschweig, Techn. Universiẗat, Diss., 2001.

Proefschrift Erasmus Universiteit Rotterdam. / Met lit. opg. - Met samenvatting in het Nederlands.

Proefschrift Rijksuniversiteit Limburg, Maastricht. / Met lit. opg. en een samenvatting in het Nederlands.

ABSTRACT Nuchal Translucency as a method of First Trimester Screening for Aneuploidy in a South African population Background Chromosomal abnormalities constitute 15% of congenital abnormalities and 50% of pregnancy losses. Twenty-five percent of these will be Trisomy 21. Down’s syndrome has a birth incidence of 2 per 1000 and constitutes 25% of severe mental handicap in the developed world. Whereas the risk assessment focuses on Trisomy 21, the fetuses that screen positive are also known to contain other defects, which include anomalies such as cardiac defects, diaphragmatic hernias, neuromuscular disorders, and rare genetic syndromes. Objective To determine the effectiveness of nuchal translucency (NT) screening in predicting aneuploidy and structural abnormalities in a South African population Setting Chris Hani Baragwanath Hospital Fetal Medicine Unit Study design Descriptive Study Methodology The Fetal Medicine Unit database was reviewed and the records of patients who had undergone NT screening between July 2003 and July 2005 were retrieved. There were no exclusions. An adjusted risk was derived from the combination of age-related risk and the risk derived from nuchal translucency screening. A positive screen was denoted by an adjusted risk of more than 1/300 and a negative screen was denoted by an adjusted risk of less than 1/300. Results A total of 428 patients had first trimester screening during this period. Thirteen patients (3%) were lost to follow up. Of the 415 cases that were analyzed, 57 patients screened positive and 356 patients screened negative. In addition, 2 fetuses with acrania were detected. The mean age for both groups of patients was 30.1 years. The crown-rump length of fetuses with a positive screen was statistically significantly shorter than fetuses that screened negative. Of the 57 patients that screened positive 24 elected to have chorionic villus sampling (CVS) which resulted in the detection of 6 chromosomal abnormalities and 2 structural abnormalities. Of the remaining 356 patients, who had screened negative, 2 had an increased adjusted risk, and one chromosomal abnormality was detected in this group. Of the remaining 354 patients, 8 elected to have CVS because of a previous history of chromosomal abnormality. All of them proved to be normal. Conclusions The use of such screening has enabled prenatal karyotyping to be focused on pregnancies at highest risk for chromosomal abnormalities regardless of age.

Pressure screens are used for contaminant removal and fibre length fractionation in the production of pulp and paper products. Axial variations and entry effects in the screen are known to occur and these variations have not been adequately quantified. This thesis describes a fundamental study of the axial variations of several factors that occur within an industrial pressure screen; namely, pulp consistency, fibre length distribution, rotor pressure pulse, and feed annulus tangential velocity. Axial variations of pulp consistency in the screen annulus and the accept chamber of the screen were studied using an internal radial sampling method. Localised pulp samples were taken and evaluated and common measures of screen performance such as fibre passage ratio and fractionation efficiency were calculated along the screen. Consistency generally increased along the length of the screen although under certain conditions the consistency toward the front of the screen was lower than the feed consistency. A two passage ratio model that incorporated forward and reverse passage ratio was derived to elucidate the flow of both fibre and fluid through the screen and their effects on overall screen performance. The passage of fibre through the screen decreased with screen length which generally had a positive effect on the fractionation efficiency toward the back of the screen. The passage of individual fibre length fractions was also studied and it was found that long fibre had a much lower passage than short fibre which caused the average fibre length in the annulus to increase. Rotor induced pressure pulse variations along the screen length were also investigated. The magnitude of the pressure pulse was significantly lower (up to 40 %) at the rear of the screen. The variation in pressure caused by the rotor is due to a Venturi effect and the shape of the rotor. The relative velocity of the fluid and the rotor, called the slip factor, also directly affects the size of the pressure pulse in the annulus. The slip factor decreases along the length of the screen due to the increase in tangential velocity of the fluid. Pressure pulse data was also used to estimate the instantaneous aperture velocity and back-flush ratio. The instantaneous aperture velocity was calculated to vary considerably from the superficial aperture velocity by up to 5 m/s in the forward direction and 10 m/s in the reverse direction. Computational Fluid Dynamics (CFD) was used to model tangential velocity changes in simplified screen annuli with axial through flow. For a smooth screen rotor the mean tangential velocity increased over the entire length of the annulus without reaching a maximum value. A step and bump rotor were modelled and the shape of the pressure pulses showed good agreement with experimentally measured pulses. The mean tangential velocity and the entrance length were found to be heavily dependant on the screen rotor used.

MMed, Community Medicine, Faculty of Health Sciences, University of the Witwatersrand / INTRODUCTION: Cervical cancer continues to be a significant cause of morbidity and mortality, particularly in women in the developing world, due to the lack of effective population screening. It has proven difficult to implement and sustain cytological screening programmes as health systems in these settings are not functional. South Africa has adopted an organised cervical screening programme, and the goal is to screen 70% of women over 30 years nationally, within ten years of initiating the programme. However, it is also necessary to ensure that women with abnormal Pap smears are treated if we are to reduce cervical cancer incidence. Ensuring treatment of abnormal Pap smears is a challenge, and current data on this is needed to inform service delivery. AIM: The study aims to assess the current status of the cervical screening programme in the Johannesburg Metro District, specifically looking at screening coverage, and referral for treatment in women with abnormal Pap smears. METHODOLOGY: Secondary analysis of data in the District Health Information System was done; and registers at a sample of primary health care clinics and their referral colposcopy services were evaluated for the period April 2007 – March 2008. Descriptive statistics were employed to analyse the data. Multivariate analysis was also done to evaluate factors associated with colposcopy attendance. vi RESULTS: Screening coverage for the district was 6.3% for 2008 and the cumulative coverage from 2000 to 2008 was 35.8%, with significant variation between subdistricts. A high proportion (19%) of smears was done in women less than 30 years. Of 557 women with abnormal Pap smears requiring further treatment, 57% were informed of their results and referred, 38% had appointments for colposcopy, and only 28% attended these appointments. Women experienced long waiting times for appointments (up to 15 months), and there was inadequate record keeping and client tracing. HIV status and the sub-district and health authority where women were screened were associated with colposcopy attendance; the referral hospital was associated with length of waiting time between Pap smear and colposcopy. CONCLUSION: Cervical screening coverage is below target, and the referral for diagnosis and treatment remains a challenge. Unless referral and access to colposcopy services is improved, increasing screening coverage will not have an impact on decreasing cervical cancer incidence and mortality. It is hoped that this study will provide the data to target interventions to improve cervical screening coverage and effective referral and treatment in the district.

According to the World Health Organization, depression affects about 350 million people worldwide. In 2014, only 50% of the adult patients were screened for depression in the community-based Federally Qualified Healthcare Center (FQHC) for which this doctorate of nursing practice (DNP) project was developed. In an effort to meet the 100% benchmark set nationally for the screening of adult patients in the primary care settings, the FQHC's quality improvement team now requires that 80% of adult patients in the clinic be screened for depression. Framed within the Iowa model of evidence-based practice, the purposes of this project were to: (a) identify an evidence-based protocol and clinical guidelines to direct the use of the Patient Health Questionnaires (PHQ)-2 and PHQ-9 depression screening tools currently available for staff, and (b) develop an educational curriculum for the staff about depression, the use of the protocol, and clinical guidelines for the tools. Two DNP educators served as content experts to evaluate the curriculum plan using a dichotomous nine-item format that revealed that the content met the objectives of the curriculum. The experts also conducted content validation of each of the 15-pretest/posttest items using a Likert scale ranging from 1(not relevant) to 4 (highly relevant). A content validation index of 1.00 showed that the experts strongly agreed that the items reflected the content of the curriculum. Recommendations were made for item construction of the pretest/posttest. The project speaks to social change through promotion of the PHQ-2 and PHQ-9 depression screening tools to facilitate appropriate diagnosis and treatment, thus promoting the health of clients, families, and the community.

Purpose and methods: Effective parental education about newborn screening (NBS) may help to maximize the benefits and minimize the harms of screening. We investigated experiences, knowledge and opinions regarding NBS education among Ontario mothers. Mothers whose infants recently received NBS were invited to complete a mailed survey (n=1712). Results: Of the 750 participants, 93% recalled their infant receiving NBS, while 69% recalled receiving information about NBS. Of this group, fewer than 50% reported receiving information prenatally, yet a majority of mothers (64%) viewed this as the most important time for education. Those who received information prenatally reported higher satisfaction (OR 2.4). The 40% of mothers who recalled being informed about the meaning of results had higher knowledge about NBS (OR 2.7) and reported higher satisfaction (OR 4.2). Conclusions: Parental education about NBS could place greater emphasis on the prenatal period and on fostering understanding about the meaning of results.

Purpose and methods: Effective parental education about newborn screening (NBS) may help to maximize the benefits and minimize the harms of screening. We investigated experiences, knowledge and opinions regarding NBS education among Ontario mothers. Mothers whose infants recently received NBS were invited to complete a mailed survey (n=1712). Results: Of the 750 participants, 93% recalled their infant receiving NBS, while 69% recalled receiving information about NBS. Of this group, fewer than 50% reported receiving information prenatally, yet a majority of mothers (64%) viewed this as the most important time for education. Those who received information prenatally reported higher satisfaction (OR 2.4). The 40% of mothers who recalled being informed about the meaning of results had higher knowledge about NBS (OR 2.7) and reported higher satisfaction (OR 4.2). Conclusions: Parental education about NBS could place greater emphasis on the prenatal period and on fostering understanding about the meaning of results.