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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.
501

Impact of the taxi recapitalisation strategy on the expenditure patterns and poverty levels of taxi-mode commuters in the Vaal / by Daphney Nontuthuzelo Dlamini-Mokhele

Mokhele, Daphney Nontuthuzelo January 2007 (has links)
The minibus taxi industry serves approximately 68% of the South Africans using public transport. It is credited with supporting black South African communities by providing a more accessible alternative to the public transportation. It has also been a primary activity for black entrepreneurship since the early 1970s up to the present. It also provides a strong example of enterprise serving as a platform for creating employment and for fighting poverty. However, its growth and prosperity is hindered by a number of challenges, some of which emanated from the past apartheid laws that restricted black economic policies. Some are related to the industry, such as continuing problems of persistent violence, at times resulting in death and safety concerns. In an effort to address these challenges, the National Department of Transport published a Taxi Recapitalisation Strategy (TRS). The TRS is not only about the replacement of old vehicles with new and safe vehicles, but presents the government with an opportunity to transform, empower and regulate the industry. The key pillars of the TRS are the scrapping of old taxi vehicles, the introduction of new and safe vehicles, effective regulations, empowerment of the taxi industry and law enforcement. This study measures the impact of the TRS on poverty levels and expenditure patterns of the taxi-mode commuters of the Vaal, situated south of Gauteng. It focuses mainly on the few townships identified; where the taxis are the most frequently used mode of transport. It has been shown that regulation of the taxi industry through the implementation of the TRS would lead to a rise in taxi fares and other consequences for the owners and users (passengers). Subsequently, this would result in increased levels of poverty and a change in expenditure patterns of most of the Vaal households. Although the levels of poverty have decreased in the townships of the Vaal as compared to 2003, the severity of poverty still remains in some households. Using the Household Subsistence Level (HSL) as the household's respective poverty line, 45.4% of the households have an income that is less than 50% of their HSL amount, indicating severe poverty. The headcount index was determined at 0.59 in 2006, indicating that 59% of households live below their poverty lines. The poverty gap index was determined at 0.45, reflecting that households lack on average 45% of income to attain a level equal to their poverty line. The impact of increases in taxi fares would then directly have a negative effect on the average standard of living of the Vaal households. To measure the impact of the TRS on expenditure patterns, affordability levels of the households of the Vaal were considered. The three scenarios used (taxi fares increase by 10%, 15%, and 20%) showed that the average monthly transport costs would rise by 9.9%, 10.3% and 10.6% respectively, following the implementation of the TRS. If user-targeted subsidies could be offered that would result in the taxi fare reduction, it could have an impact on expenditure patterns and poverty levels of the Vaal households. Applying the impact assessment model to households living below their poverty lines in the Vaal, increased government subsidy would supplement the existing incomes of these households. For instance, if a subsidy of 20% on taxi fares is offered, that is to make the taxi fare lower than the current fare, the poverty gap would decrease from 0.45 to 0.31 and the headcount index would be reduced from 0.59 to 0.48. This would reflect that households lacking income to attain a level equal to their poverty line is reduced by 14%.This suggests that the recapitalisation of the taxi fleet which is supported by a taxi fare subsidy is critical to ensure the provision of safe, affordable and efficient minibus taxis. In the case of even higher government subsidies, reduction in the cost of transport through government subsidies may supplement the existing income of households to such an extent that the headcount indexes for the population decreases even more. The study therefore concludes that poverty alleviation and improved standards of living among the Vaal households can only be achieved if appropriate subsidies which may lead to the reduction in the taxi fares can be provided. / Thesis (Ph.D. (Economics))--North-West University, Vaal Triangle Campus, 2008.
502

The relationship of self-concept in high school negro students in Muncie, Indiana, to intelligence, achievement, and grade point average

Georgi, Norman J. January 1971 (has links)
The purpose of this study was to investigate the self concepts of a group of high school Negro students in the Muncie Community Schools, Muncie, Indiana, in relation to intelligence, reading achievement, and grade point average. Specifically, the objectives were: (1) to obtain the reading achievement scores, intelligence scores, and grade point averages of a randomly selected group of Negro students in the high schools in Muncie, Indiana, (2) to identify the self-concepts of a group of high school Negro males and the self-concepts of a group of high school Negro females randomly selected from the three high schools in Muncie, Indiana, (3) to measure the relationship of the self-concept of females with their obtained intelligence scores, achievement scores, and grade Point averages, (4) to measure the relationship of the self concept of males with the obtained intelligence scores, achievement scores, and grade point averages, and (5) to measure the relationship of the self-concept of Negro students as a total group with their obtained intelligence scores, achievement scores, and grade point averages. The method of investigation used in this study included the following areas: (1) selection of participants, (2) collection of data, (3) scoring procedures, and (4) methods used in analyzing the data.Of the 278 Negro students in grades ten and eleven in the three high schools, a total sampling consisted of ninety-two (92) students, forty-five (45) males and forty-seven (47) females, or one-third of the total population of grades ten and eleven. The random selection was done during the school year, 1970-71. Two self-concept scales, Maryland Self-Concept as a Learner Scale and Brookover Self-Concept of Ability Scale were administered. Intelligence non-verbal scores, reading achievement scores, and grade point averages, as of January 21, 1971 (semester end) were obtained from the cumulative record card. All data were placed on IBM cards. The method of analysis in the study was multiple linear regression. Based on the findings of the study, the following conclusions were reached:1. The self-concepts of a group of high school Negro students are identifiable through the use of the two self-concept scales.
503

The Acute Effects of Aerobic and Resistance Exercise on Blood Glucose Levels in Type 1 Diabetes

Yardley, Jane E. 27 May 2011 (has links)
Aerobic exercise interventions involving individuals with type 1 diabetes have had little positive effect on blood glucose control as reflected by hemoglobin A1c. The few existing interventions involving resistance exercise, either alone or combined with aerobic exercise, while small in sample size, have had better outcomes. The purpose of this research program was to examine the changes in blood glucose levels during activity and for 24 hours post-exercise (as measured by continuous glucose monitoring) when resistance exercise is performed, either on its own or combined with aerobic exercise, as compared to aerobic exercise alone or no exercise. Twelve physically active individuals with type 1 diabetes performed 5 separate exercise sessions in random order separated by at least five days: 1) no exercise/control; 2) aerobic exercise (45 minutes of treadmill running at 60% VO2peak); 3) resistance exercise (45 minutes of weight lifting – 3 sets of 8 repetitions of 7 different exercises); 4) aerobic then resistance exercise (2 and 3 combined with the aerobic exercise first); 5) resistance then aerobic exercise (2 and 3 combined with the resistance exercise first). We found that resistance exercise was associated with a lower risk of hypoglycemia during exercise, less carbohydrate intake during exercise, less post-exercise hyperglycemia and more frequent (but less severe) nocturnal hypoglycemia than aerobic exercise. When aerobic and resistance exercise were combined, performing resistance exercise prior to aerobic exercise (rather than the reverse) resulted in attenuated declines in blood glucose during aerobic exercise, accompanied by a lower need for carbohydrate supplementation during exercise and a trend towards milder post-exercise nocturnal hypoglycemia.
504

Blood levels of selective antiretroviral drugs over a period of time, in Sprague-Dawley rats / Michael du Plooy

Du Plooy, Michael January 2008 (has links)
Selective antiretroviral! (ARV) drugs are primarily metabolized by cytochrome P450 (CYP) enzymes, characteristically predisposed to variation, and are therefore primarily responsible for ARV pharmacokinetic variability and associated drug interactions. For the majority of ARV drugs, the therapeutic window is narrow and imminent toxicities due to CYP inhibition or sub-therapeutic drug levels as a result of CYP induction is inevitable. Animals provide a metabolism replica to conduct detailed investigations. We endeavored to establish a rat model to screen for variability in metabolism of selective ARV drugs responsible for treatment failure and drug interactions, over time in the liver and serum. Male Sprague-Dawley rats (n = 24) were divided into 6 groups: methylcellulose, 160mg/kg/day (n = 24) (control); efavirenz, 160mg/kg/day (n = 18); ritonavir, 20 mg/kg/day (n = 18); ritonavir, 20 mg/kg/day and verapamil 5 mg/kg/day (n = 18); Kaletra® (ritonavir/lopinavir), 20 mg/kg/day, (n = 18); Kaletra® (ritonavir/lopinavir), 20 mg/kg/day and verapamil 5 mg/kg/day (n = 18). Treatment duration varied from one day (single dose), 7 or 21 days. Blood samples were collected after decapitation on days 1, 7 and 21. A sensitive and rapid liquid chromatograph (LC) interfaced to a quadrupoie mass spectrometer (MS) and coupled with electrospray ionization (ESI) method was employed for the blood sample determinations. One single injection was required to simultaneously quantify efavirenz, lopinavir and ritonavir within the linear concentration range of 78 - 5000 ng/ml. Efavirenz blood levels increased statistically significantly (p < 0.05) from day 1 to day 21 with distinct steady state achievement prior to day 7. The levels of ritonavir increased statistically significantly (p < 0.05) from day 7 to 21 when administered alone and statistically significantly (p < 0.01) from day 1 to 21 when administered as the ritonavir/lopinavir combination. The levels of lopinavir also increased statistically significantly (p<0.01) from day 1 and 21 in the ritonavir/lopinavir combination. However, the inclusion of a P-glycoprotein inhibitor, verapamil, increased both the ritonavir (administered alone) and lopinavir blood levels significantly (p < 0.05) at day 1. The ritonavir levels were also significantly increased on day 21 (p < 0.05). When verapamil was added to the ritonavir/lopinavir combination the levels of ritonavir increased statistically significantly (p < 0.01) from day 1 to 21. A rat model can be used to detect changes in metabolism over time as measured by blood levels. The influence of drug interactions, such as verapamil, on ARV drug metabolism can be investigated by this model. These results will be substantiated by PCR liver results in the future. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2009.
505

Die effek van 'n fisieke-aktiwiteits-, dieet en gedragsveranderingsintervensie op obesiteit by 9-12 jarige kinders / C. Kemp

Kemp, Chanelle January 2008 (has links)
Various research studies have indicated that the prevalence of overweight and obesity among children and adolescents has increased worldwide and has, therefore, become a serious health problem. Besides the various health implications of childhood obesity, it can also have psychological consequences for these children and they have a greater risk than a normal weight child to suffer from poor self perception. The effect of a physical activity, diet and behaviour modification intervention on the total energy expenditure, physical activity levels and self perception of 9 to 12 year old overweight and obese children is, however, not clear. The aim of the study was firstly to determine the effect of a physical activity, diet and behaviour modification intervention on the total energy expenditure and physical activity levels of 9 to 12 year old overweight and obese children. Secondly, to determine the effect of such an intervention on the self perception, and more specifically athletic and physical self perception of these children. An availability sample of 20 overweight and obese subjects (13 girls and 7 boys) between the ages of 9 and 12 years with a mean age of 11 years, participated in a 13 week (3 times/week) multidisciplinary intervention programme. Actical® monitors were used to monitor energy expenditure as well as physical activity levels during 2 weekdays and 1 weekend day before and after the intervention programme. From the results, analyzed by means of t-testing and linear regression, it is apparent that the total energy expenditure of the group, when adjusted for the effect of the intervention, showed a significant increase (p < 0.05) and body fat percentage as well as waist and upper arm circumferences decreased significantly. Although not significant, a decrease of 2,9 kg in body mass and 2,00 kg.rh" in body mass index were also indicated. However, the moderate and high intensity physical activity levels of the groups decreased significantly after the intervention programme. A possible reason for this decrease can be ascribed to the fact that the post-test took place during the school holidays. Further analysis of the data also indicated that the group slept longer hours, which increased their hours spent in the sedentary activity zone. The group also spent more time during the day watching television which also contributed to a decrease in the percentage of time spent in the moderate intensity zone. It is, however, concluded that increased total energy expenditure alone could not bring about effective weight loss and must, therefore, be accompanied by activity in the moderate and high intensity zones. For the purpose of the second aim, twenty children (13 girls and 7 boys) between the ages of 9 and 12 years, with a mean age of 11 years, participated in a 13 week multidisciplinary intervention programme (3 times per week). Eighteen children (11 girls and 7 boys) between the ages of 9 and 12 years, with a mean age of 11 years, served as a control group. Self perception, which consisted of 6 subcomponents, was determined by using the Harter Scale for Self Perception (Harter, 1985). It is clear from the results of the t-test (p < 0.05) that all subcomponents of self perception of the experimental group, especially physical, athletic and global self perception, increased significantly in relation to the control group which remained the same in all the subcomponents (p > 0.05), while a decrease in their social self perception was noted (p < 0.05). The experimental and control group did not differ significantly before the intervention programme, therefore the significant differences with regard to the subcomponents during the post-test, confirm the effect of the programme. On the basis of the abovementioned results the assumption can be made that a multidisciplinary intervention programme holds various benefits for overweight and obese children and is, therefore, another strategy in the prevention of overweight and obesity in children in South Africa. A multidisciplinary intervention programme, as used in this programme, is not only advantageous for weight loss in overweight and obese children, but also significantly improves their self perception. / Thesis (M.Sc. (Human Movement Science))--North-West University, Potchefstroom Campus, 2009.
506

Studies of leaching, recovery and recycling of heavy metals

Askari, Hallo Mustafa January 2008 (has links)
The leachability of cadmium, cobalt, copper, lead, nickel and zinc metals and their oxides, sulfides and carbonates by water, 0.5 mol dm-3 CH3COOH, 0.1 mol dm -3 HCl/NaCI (1: 1 mixture) and 2 mol dm -3 HNO3 is reported. The concentrations of the leached heavy metals are compared with the trigger levels set by World Health Organisation (WHO). Three leaching solutions (nitric, sulfuric and hydrochloric acids) were used to extract copper, zinc, cobalt, nickel, iron and lead from spent catalysts prior to the application of separation technologies. Leaching experiments were conducted using both traditional methods and a microwave-assisted extraction technique. Data are provided on the effects of leaching temperature, leaching time, solid to liquid ratio and acid concentration on the extraction of different metals. The use of 2 mol dm-3 sulfuric acid at 50°C for 60 minutes and at a solid/liquid (S/L) ratio of 1: 25 achieved more than 90% extraction for all the metals studied. A comparison of the results from traditional and microwave extraction techniques demonstrates that microwave heating reduced the time required to obtain maximum metal extraction. The kinetics for the traditional extraction procedure showed that diffusion was the ratecontrolling process, but it was not possible to conclusively establish the rate controlling process for the microwave leaching. The feasibility of using an electrodialysis process to separate metal ions, such as copper from zinc, was examined. A laboratory-scale three compartments membrane system was designed, constructed, used and optimised for the separation process. The separation of copper from zinc in the electrodialysis process exploited the greater stability of the Cu-EDTA complex compared with the Zn-EDTA complex. It was observed that Zn 2+ ions migrated through the cation-exchange membrane from central compartment to catholyte and, simultaneously, the negative Cu-EDTA complex transferred to the analyte compartment crossing the anion exchange membrane. The technique was successfully used to separate mixtures of Cu: Cd and Zn: Ni. The technique could not, however, be used for the separation of Zn from Cd. An adsorption process was used to prepare copper, iron, nickel and zinc oxides catalysts on y-A1203 as support. The materials prepared were used in a fixed bed reactor to assess the catalytic oxidation of volatile organic compounds (methane and ethane) in air. Cu/y- A1203 was found to be the most promising catalyst for the complete oxidation of methane and ethane at temperatures of 575°C and 525°C, respectively. Increasing the calcination temperature in the drying and pre-treatment of the catalysts resulted in a decrease in the catalytic activity.
507

The development and evaluation of functional electrical stimulation rowing for health, exercise and sport for persons with spinal cord injury

Hettinga, Dries Martijn January 2006 (has links)
At the beginning of this project it was known that functional electrical stimulation (FES) rowing was technically feasible, but no studies on health benefits had been conducted and it was unclear what levels of fitness could be reliably attained by spinal cord injured (SCI) users. This thesis shows that training with the first-generation of the FES-rowing system (RowStim II), seven paraplegics achieved high V02peak values (21.0 - 27.9 ml-kg-1-min-1) and a significant (10%) increase in V02peak. This was also found to significantly improve insulin sensitivity and leptin levels but it had no significant effect on lipid profiles or body composition, possibly caused by technological limitations of the RowStim 11. However, training volumes were positively correlated with improvements in lipid profile and body composition. This motivated further technical development of the RowStim to enable paraplegics to train harder and longer. The development included a more stable seat configuration with redesigned trunk retaining straps, a rigid low friction carriage/brake system, improved leg stabiliser, improved stimulation control and a gravity-assisted return phase. This RowStim III has enabled paraplegics to participate in the British (2004, 2005 and 2006) and World Indoor Rowing Championships (2006). The rowers have achieved higher exercise intensities (26.8 -31.0 ml. kg- I .min-1) and increased exercise volumes (1,150 kcal-week-1) with the RowStim III. Such levels of physical activity, which are difficult to achieve for paraplegics using traditional exercises, are correlated with significant health benefits in the able-bodied. Preliminary results suggest that perfusion of the quadriceps muscle during FES-rowing might limit the exercise time in novice rowers. Other preliminary data from pressure mapping indicate that there is a dynamic pattern during FES-rowing, which might reduce the risk for pressure sores during FES-rowing. This thesis shows that FES-rowing is now a rapidly developing exercise modality, which has been shown to enable safe and well-tolerated exercise for individuals with SCI. It can offer unprecedented levels of cardiovascular fitness, competitive challenges and potentially important health benefits.
508

Concept to practice - applied inclusiveness : an emergent model of socially inclusive practice

Richards, Sandra D. January 2004 (has links)
Research indicates that large numbers of young people are underachieving in UK schools, and that school exclusion levels are unacceptably high. In addition, there are increased numbers of students unable to secure a place in mainstream schools. These unplaced and excluded young people are described by New Labour as `vulnerable', `disaffected' or at risk of disaffection (Social_Exclusion_Unit 1998b). The numbers of young people considered `disaffected' indicates a national problem and so, in response to this, there is a government led drive to `socially include' `excluded' young people and young people considered `at risk' of `exclusion'. This UK study examines the principles and practices of practitioners working with identified `at-risk' and `hard to reach' populations. This thesis seeks to unpack this complex situation of social `exclusion' and `inclusion' as it relates to education by asking; who are the `actors' in this expanding world of `social inclusion'? How can some practitioners `reach' and `include' so called `hard to reach' `disaffected' young people? This research explores socially inclusive practice. It aims to investigate whether a model of socially inclusive practice exists or can be established that could be used by educators, parents, human resource (HR) professionals and others concerned with client services in the helping professions. Social exclusion is one of the key concerns of the New Labour agenda. Inclusive education is perceived as central to promoting social inclusion (Social_Exclusion_Unit 1998b) and as a result there are a number of social inclusion projects operating throughout the UK. These projects generally offer provision for young people who, in the judgement of excluding mainstream practitioners, should be placed outside of their responsibility. These excluding practices reflect the values and ideal of the institution and how they perceive their own ability to respond to the total needs of the learner in their care. Excluded young people are typically referred to pupil referral units (PRU's), study centres or other education provision established to meet the statutory requirement of the education authority to maintain education provision. The practitioner is the focus of this investigation and preliminary issues associated with an investigation into social inclusion practice will be considered in an attempt to identify `what works' in opening up educational opportunities to an inclusive culture. This study then, examines the practice and rationale employed by staff at a project providing education otherwise than at school (EOTAS) to young people unplaced, excluded or at risk of exclusion from mainstream school by analysing empirical data collected over a 3-year period using qualitative instruments. Grounded Theory is the methodological approach used to elicit data and the findings provide valuable insights into inclusive education practices. In addition, a number of relevant and important issues are identified. The theoretical model that emerges is informed by the insights and issues that emerge in this, the first major UK study, into inclusive practice in education where the practitioner is the main focus of the study. This research puts forward a model of professional understanding for inclusive education and makes a contribution to the development of new approaches. The results offer clear indicators for a transferable framework of socially inclusive practice.
509

マイクロ-メゾ・ダイナミックスに基づくメディアコミュニケーションの心理的影響に関するモデル

五十嵐, 祐, Igarashi, Tasuku 27 December 2004 (has links)
国立情報学研究所で電子化したコンテンツを使用している。
510

mRNA Levels of ERG, KVLQT1 and minK in Rabbit Right and Left Ventricles

LU, Zhibo, HOJO, Mayumi, YASUI, Kenji, KODAMA, Itsuo, KAMIYA, Kaichiro 12 1900 (has links)
国立情報学研究所で電子化したコンテンツを使用している。

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