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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.
71

The Effects of Resistance Training on Strength and Body Composition in Postpartum Women

Pratt, Katherine Bishop 11 August 2010 (has links) (PDF)
The postpartum period represents a high-risk period for body weight retention and obesity. Several studies have investigated the role of aerobic exercise on postpartum weight retention and other body composition outcomes; however, there has been little attention given to resistance training in postpartum women. Thus, the purpose of this four-month randomized study was to determine the effectiveness of resistance training on strength, body composition, return to pre-pregnancy weight, and bone mineral density (BMD) in postpartum women. Sixty postpartum women were randomly assigned to either a resistance training group or a comparison group. The resistance training group participated in a progressive resistance training program twice weekly for four months. The comparison group participated in a flexibility program twice weekly for four months. Strength changes were assessed for the upper body (bench press), lower body (leg press), and the core (abdominal curl-ups). Body composition, including BMD, was measured by dual energy x-ray absorptiometry. Over the four-month study, the resistance training group demonstrated a 36.7% increase in bench press, a 31.1% increase in leg press, and a 222.6% increase in abdominal curl-ups (p < 0.05). The flexibility group improved by 7.7% for bench press, 6.6% for leg press, and by 43.0% for abdominal curl-ups (p < 0.05). Group*period interactions were significant for the leg press, bench press, and abdominal curl-ups (p < 0.05). Both groups decreased in body weight, body fat percentage, and fat tissue (p < 0.05). Neither group significantly changed in lean tissue, whole body BMD, and hip BMD (p > 0.05). Group*period interactions were not significant for any body composition outcome (p > 0.05). These results suggest that a twice weekly resistance training program is superior to flexibility training to increase strength; however, resistance training may not be enough to influence body composition to a greater extent than flexibility training in postpartum women. More research is warranted.
72

Köldbryggor i Småhus : Stämmer schablonpåslaget?

Khalifa, Rahman January 2022 (has links)
Idag står mänskligheten inför stora förändringar i klimatet, men en ansträngning från alla kan dessa förändringar motverkas. Detta examensarbete är en påpekning som kan leda till en bättre miljö.   Syftet med examensarbetet är att i samverkan med företaget Lönn Energi undersöka och analysera kända köldbryggor i två småhus. Som ligger i närheten av Gävle och jämföra köldbryggsandelen i husen med schablon-påslaget om 20%.  Det som ska beräknas är andelen linjära köldbryggor i förhållande till värmegenomgångskoefficienten, Som resultat visar arbetet att för de två husen som undersöktes att andelen köldbryggor i förhållande till Um går på 4,5% för huset i Årsunda och 8,4% för huset i Lingbo. / Today, humanity is facing major climate changes, but with the efforts of all, these changes can be prevented. This thesis work is a remark that can lead to a better environment.  The purpose of the thesis is to investigate and analyze known thermal bridges in two single-family houses which is located near Gävle. And to compare the thermal bridges percentage in the houses with the recom-mended addition of 20 % in collaboration with Lönn Energi.   As a result, the work shows that for the two houses examined the propor-tion of thermal bridges in relation to heat transfer coefficient Um is 4.5% for the house in Årsunda and 8.4% for the house in Lingbo.
73

Influence of Fill Percentage and Baking Parameters on the Feedability of Metal-Cored Arc Welding Wires

Black, Angelica Marie 12 December 2022 (has links)
No description available.
74

An Initial Study to Determine a Friction-Factor Model for Ground Vegetation

Kenney, Peter Martin January 2009 (has links)
No description available.
75

Alcohol intake and cardiovascular function of black South Africans : a 5-year prospective study / Mandlenkosi Caswell Zatu

Zatu, Mandlenkosi Caswell January 2015 (has links)
Motivation Alcohol consumption is one of the major risk factors of cardiovascular disease (CVD). Excessive alcohol drinking is the fifth leading cause of death worldwide and the prevalence of alcohol abuse continues to increase especially in low-income areas of sub-Saharan Africa. The alarming rate of urbanisation seems to be the driving force for excessive alcohol intake in the developing world. In addition to its influence on CVD, heavy drinking also results in a number of non-cardiovascular consequences that include injury, risky sexual behaviour, violent crime and family dysfunction among black South Africans, contributing to high mortality. Moreover, the highest number of individuals with human immunodeficiency virus (HIV) infection in South Africa is partly attributable to high intake of alcohol. HIV remains a major concern in South Africa with significant funding diverted to address the pandemic. The continued increases in mortality from preventable outcomes such as stroke, myocardial infarction and renal failure are largely due to urbanisation, poverty and dysfunctional health systems working with limited budgets. These are some of the factors requiring in-depth study of the scientific aspects of alcohol intake in South Africa. Although there is enough evidence that links excessive drinking with hypertension and CVD, the markers of alcohol intake – self reporting of alcohol, gamma-glutamyltransferase (GGT) and carbohydrate deficient transferrin – are still not specific enough to isolate other confounding factors in the association of alcohol intake with CVD. The markers of alcohol that independently predict CVD and mortality need to be explored. Finally, the severe lack of longitudinal investigations on alcohol-related hypertension development and total mortality in black South Africans has compromised the early identification of risk factors associated with these outcomes. This study will therefore attempt to address the limited availability of longitudinal studies and stimulate interest for continued investigation. Aim The aim of this study was to investigate whether alcohol intake of black South Africans is related to specific measures of cardiovascular function (change in blood pressure (BP), hypertension development) and mortality over a period of 5 years. Methodology This study was based on the international Prospective Urban and Rural Epidemiology (PURE) study which includes 26 countries, investigating the cause and development of cardiovascular risk factors in low, middle and high income countries. This South African leg of the PURE study started in 2005 in which the baseline data was collected from 2021 black South Africans from rural and urban areas in Ikageng, Ganyesa and Tlakgameng in the North West Province. Eleven participants presented with missing data, leaving 2010 participants with complete datasets at baseline. However, data from these 11 participants was useful, especially for Chapter 4. All participants gave informed consent and the Ethics committee of the North-West University (Potchefstroom Campus) approved the study. The follow-up data collection was done in 2010. General health questionnaires, anthropometric measurements, lipid profiles and cardiovascular measurements were taken both at baseline and follow-up using appropriate methods. We also collected blood samples and performed biochemical analyses for lipid markers, liver enzymes, inflammatory markers and percentage carbohydrate deficient transferrin (%CDT). Finally, we obtained data on cardiovascular and non-cardiovascular mortality through verbal autopsy and death certificates. We made use of analysis of variance (ANOVA) and Chi-square tests to compare means and proportions, respectively. We used dependent t-tests and the McNemar test to compare baseline and follow-up variables. Furthermore, we employed single and partial linear regression analyses to correlate alcohol markers with each other and with the cardiovascular measures. Multiple regression analyses were used to correlate dependent variables in the study with various independent variables as required. Finally, we employed multivariable-adjusted Cox regression analyses to assess the association of the selected alcohol markers with mortality while adjusting for several independent variables. Results and Conclusions of each manuscript - With the first research article (Chapter 4), we aimed to compare self-reported alcohol intake estimates with GGT and %CDT, considering their relationship with percentage change in brachial blood pressure (BP) and central systolic blood pressure (cSBP) over 5 years. The results indicated that only self-reported alcohol intake independently predicted % change in brachial BP and cSBP. This was not found for the biochemical markers GGT and %CDT. Self-reported alcohol intake seems to be an important measure to implement by health systems in low income areas of sub-Saharan Africa, where honest reporting is expected. - Given the likely presence of high GGT levels in both alcohol consumption and non-alcoholic fatty liver disease (NAFLD), the second manuscript (Chapter 5) aimed to compare the cardiovascular and metabolic characteristics of excessive alcohol users and individuals with suspected NAFLD (confirmed with self-report, GGT and %CDT). We found that different sex and cardiometabolic profiles characterised excessive alcohol users and individuals suspected with NAFLD. Lean body mass and male sex were the dominant characteristics in excessive alcohol use while the NAFLD group had a dysmetabolic profile with obese women making up the higher proportion of this group. In excessive alcohol users systolic blood pressure and pulse pressure were independently associated with high-density lipoprotein cholesterol. Diastolic blood pressure showed a significant correlation with waist circumference. These disparate profiles may guide healthcare practitioners in primary healthcare clinics to identify individuals with elevated GGT levels who may suffer from NAFLD or alcohol overuse. These results emphasise the importance of modifiable risk factors as the main contributors to CVD and that lifestyle change should be the main focus in developing countries such as South Africa. - The third manuscript (Chapter 6) aimed to determine the measure of alcohol intake (selfreported alcohol intake, GGT and %CDT) that related best with hypertension development, cardiovascular and all-cause mortality over 5 years in the same population of black South Africans. We found that GGT was the only independent predictor of hypertension development, cardiovascular as well as all-cause mortality. Moreover, self-reporting of alcohol intake predicted incident hypertension, confirming our findings from Chapter 4. The third marker, %CDT, a highly specific marker of alcohol intake, was not related with any outcome variable, perhaps due to its low sensitivity. Although self-reported alcohol intake is useful in low-resource primary healthcare settings, measurement of GGT is encouraged due to its predictive value for hypertension and mortality. GGT represents alcohol intake, non-alcoholic steatohepatitis and obesity - all known to have severe cardiovascular consequences. Discussion and Conclusions Excessive alcohol intake remains a major concern in the development of hypertension, CVD and premature death in sub-Saharan Africa. Despite their weaknesses such as bias and nonspecificity, self-reporting of alcohol consumption and GGT emerged as reliable alcohol markers that independently predicted 5-year change in BP, hypertension development and total mortality in this population. Serum %CDT did not show any association with the mentioned cardiovascular markers. Finally, we were also able to show that black South Africans with suspected NAFLD (i.e. with high GGT levels who do not consume alcohol) are typically obese women, whereas lean men were more likely to have high alcohol consumption. Further prospective investigations are encouraged regarding (a) these mentioned associations, as well as (b) other self-reporting estimates such as quantity and frequency of drinking and (c) the use of %CDT as a highly specific marker of alcohol intake. The simultaneous presence of HIV infection in alcohol abuse in this population also warrants further investigation. / PhD (Physiology), North-West University, Potchefstroom Campus, 2015
76

Alcohol intake and cardiovascular function of black South Africans : a 5-year prospective study / Mandlenkosi Caswell Zatu

Zatu, Mandlenkosi Caswell January 2015 (has links)
Motivation Alcohol consumption is one of the major risk factors of cardiovascular disease (CVD). Excessive alcohol drinking is the fifth leading cause of death worldwide and the prevalence of alcohol abuse continues to increase especially in low-income areas of sub-Saharan Africa. The alarming rate of urbanisation seems to be the driving force for excessive alcohol intake in the developing world. In addition to its influence on CVD, heavy drinking also results in a number of non-cardiovascular consequences that include injury, risky sexual behaviour, violent crime and family dysfunction among black South Africans, contributing to high mortality. Moreover, the highest number of individuals with human immunodeficiency virus (HIV) infection in South Africa is partly attributable to high intake of alcohol. HIV remains a major concern in South Africa with significant funding diverted to address the pandemic. The continued increases in mortality from preventable outcomes such as stroke, myocardial infarction and renal failure are largely due to urbanisation, poverty and dysfunctional health systems working with limited budgets. These are some of the factors requiring in-depth study of the scientific aspects of alcohol intake in South Africa. Although there is enough evidence that links excessive drinking with hypertension and CVD, the markers of alcohol intake – self reporting of alcohol, gamma-glutamyltransferase (GGT) and carbohydrate deficient transferrin – are still not specific enough to isolate other confounding factors in the association of alcohol intake with CVD. The markers of alcohol that independently predict CVD and mortality need to be explored. Finally, the severe lack of longitudinal investigations on alcohol-related hypertension development and total mortality in black South Africans has compromised the early identification of risk factors associated with these outcomes. This study will therefore attempt to address the limited availability of longitudinal studies and stimulate interest for continued investigation. Aim The aim of this study was to investigate whether alcohol intake of black South Africans is related to specific measures of cardiovascular function (change in blood pressure (BP), hypertension development) and mortality over a period of 5 years. Methodology This study was based on the international Prospective Urban and Rural Epidemiology (PURE) study which includes 26 countries, investigating the cause and development of cardiovascular risk factors in low, middle and high income countries. This South African leg of the PURE study started in 2005 in which the baseline data was collected from 2021 black South Africans from rural and urban areas in Ikageng, Ganyesa and Tlakgameng in the North West Province. Eleven participants presented with missing data, leaving 2010 participants with complete datasets at baseline. However, data from these 11 participants was useful, especially for Chapter 4. All participants gave informed consent and the Ethics committee of the North-West University (Potchefstroom Campus) approved the study. The follow-up data collection was done in 2010. General health questionnaires, anthropometric measurements, lipid profiles and cardiovascular measurements were taken both at baseline and follow-up using appropriate methods. We also collected blood samples and performed biochemical analyses for lipid markers, liver enzymes, inflammatory markers and percentage carbohydrate deficient transferrin (%CDT). Finally, we obtained data on cardiovascular and non-cardiovascular mortality through verbal autopsy and death certificates. We made use of analysis of variance (ANOVA) and Chi-square tests to compare means and proportions, respectively. We used dependent t-tests and the McNemar test to compare baseline and follow-up variables. Furthermore, we employed single and partial linear regression analyses to correlate alcohol markers with each other and with the cardiovascular measures. Multiple regression analyses were used to correlate dependent variables in the study with various independent variables as required. Finally, we employed multivariable-adjusted Cox regression analyses to assess the association of the selected alcohol markers with mortality while adjusting for several independent variables. Results and Conclusions of each manuscript - With the first research article (Chapter 4), we aimed to compare self-reported alcohol intake estimates with GGT and %CDT, considering their relationship with percentage change in brachial blood pressure (BP) and central systolic blood pressure (cSBP) over 5 years. The results indicated that only self-reported alcohol intake independently predicted % change in brachial BP and cSBP. This was not found for the biochemical markers GGT and %CDT. Self-reported alcohol intake seems to be an important measure to implement by health systems in low income areas of sub-Saharan Africa, where honest reporting is expected. - Given the likely presence of high GGT levels in both alcohol consumption and non-alcoholic fatty liver disease (NAFLD), the second manuscript (Chapter 5) aimed to compare the cardiovascular and metabolic characteristics of excessive alcohol users and individuals with suspected NAFLD (confirmed with self-report, GGT and %CDT). We found that different sex and cardiometabolic profiles characterised excessive alcohol users and individuals suspected with NAFLD. Lean body mass and male sex were the dominant characteristics in excessive alcohol use while the NAFLD group had a dysmetabolic profile with obese women making up the higher proportion of this group. In excessive alcohol users systolic blood pressure and pulse pressure were independently associated with high-density lipoprotein cholesterol. Diastolic blood pressure showed a significant correlation with waist circumference. These disparate profiles may guide healthcare practitioners in primary healthcare clinics to identify individuals with elevated GGT levels who may suffer from NAFLD or alcohol overuse. These results emphasise the importance of modifiable risk factors as the main contributors to CVD and that lifestyle change should be the main focus in developing countries such as South Africa. - The third manuscript (Chapter 6) aimed to determine the measure of alcohol intake (selfreported alcohol intake, GGT and %CDT) that related best with hypertension development, cardiovascular and all-cause mortality over 5 years in the same population of black South Africans. We found that GGT was the only independent predictor of hypertension development, cardiovascular as well as all-cause mortality. Moreover, self-reporting of alcohol intake predicted incident hypertension, confirming our findings from Chapter 4. The third marker, %CDT, a highly specific marker of alcohol intake, was not related with any outcome variable, perhaps due to its low sensitivity. Although self-reported alcohol intake is useful in low-resource primary healthcare settings, measurement of GGT is encouraged due to its predictive value for hypertension and mortality. GGT represents alcohol intake, non-alcoholic steatohepatitis and obesity - all known to have severe cardiovascular consequences. Discussion and Conclusions Excessive alcohol intake remains a major concern in the development of hypertension, CVD and premature death in sub-Saharan Africa. Despite their weaknesses such as bias and nonspecificity, self-reporting of alcohol consumption and GGT emerged as reliable alcohol markers that independently predicted 5-year change in BP, hypertension development and total mortality in this population. Serum %CDT did not show any association with the mentioned cardiovascular markers. Finally, we were also able to show that black South Africans with suspected NAFLD (i.e. with high GGT levels who do not consume alcohol) are typically obese women, whereas lean men were more likely to have high alcohol consumption. Further prospective investigations are encouraged regarding (a) these mentioned associations, as well as (b) other self-reporting estimates such as quantity and frequency of drinking and (c) the use of %CDT as a highly specific marker of alcohol intake. The simultaneous presence of HIV infection in alcohol abuse in this population also warrants further investigation. / PhD (Physiology), North-West University, Potchefstroom Campus, 2015
77

Režimová opatření pro úpravu životního stylu pro osoby se sclerosis multiplex / Lifestyle changes to lifestyle modification for people with multiple sclerosis

Libá, Martina January 2014 (has links)
Title: Lifestyle changes to lifestyle modification for people with multiple sclerosis Aim: Designing a program that affects lifestyle, fitness and physiological parameters in subjects of different age and different sex of people who have a diagnosis of multiple sclerosis (MS). Method: A literary review to make a summary of knowledge on MS and use of physical activities as opportunities to influence the overall lifestyle of people with MS. Results: The result is an overview of the programs and its evaluation - changes in physiological parameters, condition and subjective feelings. We found that when respecting the state of health programs may be implemented in the long term. Conclusion: The success of interventions depends on collaboration, time availability, but also the respecting of the designed programs of people involved. At the same time, however, assumes that an active lifestyle affects the mental aspect of individuals and their subjective feelings. Keywords: Multiple sclerosis, physical condition, subjective feelings, body fat percentage, body water percentage, body weight, muscle dysbalance
78

FRUIT AND VEGETABLE CONSUMPTION OF DIVISION I COLLEGIATE FOOTBALL AND VOLLEYBALL PLAYERS PRE- AND POST-DEREGULATION OF SNACKS BY THE NCAA

Ludwig, Emily 01 January 2015 (has links)
The deregulation of snacks by the National Collegiate Athletic Association (NCAA) permits institutions to provide enhanced snacks incidental to participation. Athletes may now have the opportunity to improve their diet quality. The purpose of this research was to assess the consumption of fruits and vegetables as well as body composition of Division I collegiate athletes. The sample included 19 American football players and 8 volleyball players. Paired t-tests were performed to compare fruit intake, vegetable intake, and body fat percentage pre- and post-deregulation of snacks. Linear regression models were used to determine correlations between change in fruit intake and change in body fat percentage and change in vegetable intake and change in body fat percentage. There were no significant differences in the paired t-tests; however, there was a significant correlation in increasing fruit intake, vegetable intake, and decreasing body fat percentage among football players. Results suggest that regular contact with a Registered Dietitian may improve diet quality, and providing nutrient-dense foods planned by a Registered Dietitian to college athletes may improve body fat percentage.
79

Investigating certain share buyback transactions by companies listed on the JSE for the period 2000 to 2005

De Goede, Andre 12 1900 (has links)
Thesis (MBA (Business Management))--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Prior to 30 June 1999 companies in South Africa were not allowed to buy back their own shares. Amendments to the Companies Act, the Companies Amendment Act (Act 37 of 1999) radically changed the philosophy around capital maintenance. The result of this amendment is that a company is allowed to buy back its own shares and finance the backbuying of its shares under certain circumstances. A sample of 140 companies listed on the Johannesburg Securities Exchange for the period 2000 to 2005 was selected. The backbuying of shares by the relevant company, subsidiary and trust was analysed for the period 2000 to 2005. For the purposes of this empirical study, the financial sector, as well as the alternative exchange, that is focussed on good quality small and medium-sized high growth companies, were excluded during sample selection. The outcome of this exploratory study is the identification of the fact that a share buyback took place or not in Tables 4.1 and 4.2; a summary of the number of shares bought back in Table 4.3; and, in Table 4.4, a summary of the number of shares bought back, expressed as a percentage of the weighted average number of shares in issue. / AFRIKAANSE OPSOMMING: Maatskappye in Suid-Afrika was voor 30 Junie 1999 deur die Maatskappywet verbied om hul eie aandele terug te koop. Wysigings aan die Maatskappywet, naamlik die Wysigingswet op Maatskappye (wet 37 van 1999) het ’n radikale verandering bewerkstellig in die filosofie rakende kapitaalinstandhouding. Die gevolg van dié wysigingswetgewing is dat maatskappye sedert 30 Junie 1999 hul eie aandele kan terugkoop en in sekere omstandighede die aankoop van hul eie aandele finansier. ’n Steekproef van 140 genoteerde maatskappye op die Johannesburgse Aandelebeurs is geselekteer vir die tydperk 2000 tot 2005. Die terugkooptransaksies van aandele deur die betrokke maatskappy, filiaal en trust is opgesom vir die tydperk 2000 tot 2005. Hierdie empiriese ondersoek het die finansiële sektor, asook die alternatiewe beurs van die Johannesburgse Aandelebeurs, wat fokus op goeie kwaliteit klein en mediumgrootte maatskappye met groot groeipotensiaal, tydens die steekproefseleksie uitgesluit. Die resultate van hierdie empiriese ondersoek is die identifisering en opsomming van die terugkooptransaksies van aandele vir die steekproef in Tabelle 4.1 en 4.2; ’n opsomming in Tabel 4.3 van die getal aandele teruggekoop; en ’n opsomming in Tabel 4.4 van die getal aandele teruggekoop, uitgedruk as ’n persentasie van die gemiddelde getal uitgereikte aandele.
80

Characterisation of shape of fine recycled crushed coloured glass and the effect on the properties of structural concrete when used as a fine aggregate replacement

Koh, Chon Jin January 2014 (has links)
In order to reduce the use of landfilling within waste management great emphasis is being placed on waste reduction and recycling. Each year in the UK approximately 2.5 Mt of waste glass is produced and approximately half of this waste is not recyclable. Therefore alternative ways need to be found for using waste glass and one possibility is to use it within concrete as a replacement for cement and/ or aggregate. In the research programme concrete mixes were tested which had 0%, 25%, 50% and 100% of the fine aggregate replaced by crushed waste glass. All glass was originally in bottle form and was crushed to produce ‘sand’ which had a grading curve more-orless identical to fine aggregate obtained from a commercial supplier. Three colours of glass were studied, i.e. flint (clear), amber and green. Concretes were also made which contained a mixture of colours (in proportion according to the weight of each type of waste glass produced annually within the UK) and also a mixture of unwashed waste glasses. The overall concrete mix adopted for investigation, i.e. 1:2:4, was selected because of its wide use within industry, and all concrete was made with a water:cement content of 0.6 without the addition of plasticiser or ASR-retarding agents. The suite of laboratory tests included; slump, flow, initial and final setting time, ultrasonic pulse velocity, water absorption by immersion and capillarity rise, ASR measurement (volumetric and linear), compression strength at ages from 7 days to 365 days. Techniques of developed digital imaging and processing have been applied to the glass aggregate to quantify various particle shape factors, i.e. aspect ratio, percentage concavity, Riley inscribed sphericity and surface texture index. Statistical analysis has been used to compare the distribution of particle forms present within the fine aggregate materials used in the experimental work. Dimensional changes (in three orthogonal directions) were measured as concrete cubes hardened over a period up to 365 days. The length changes of concrete prisms were also measured over the same period of time. The resultant data indicated that a fine aggregate which comprised 25% glass and 75% sand would be categorised as “non-expansive”, i.e. the same as the sand on its own. As the proportion of glass in the fine aggregate became greater than the aggregate became more expansive but it did not exceed recommended limits.

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