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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.
291

The impact of physical activity on selected health risk factors and medical costs of employees working within a financial institution / Wandra Marais (née Van der Merwe)

Marais, Wandra January 2008 (has links)
For employees to optimally perform at work, it is important that they are healthy. The employee is under constant work pressures that affects their health behaviour. The aim of this research is to look at the evident health risks of employees working within a financial institution, to analyze how physical activity influences these health risk factors and their medical costs. In this study a sample of 9860 self selected employees, aged between 18 and 64 (35.3 ± 10.7 years), was used. These employees are spread over all the provinces of South Africa and from all racial groupings. Differentiation was made between employees who were on chronic medication and those who were not. The Health Risk Assessment (HRA) questionnaire developed and provided by the medical aid of the institution was used as the analysis tool. Medical expenditures of the sample group were also provided by the medical aid and investigated. A national network of registered Biokineticists administered the implementation of the HRA, based on a set protocol. ANOVA was used for statistical data analysis - providing descriptive and summarising statistics. One-way analysis of variance was used to determine relationships between variables. It is clear from the descriptive data that the tendencies of selected health risks were high. The results also show that 37.6% (Diastolic) and 47.87% (Systolic) of the sample group comply with the normal borders of blood pressure. With regards to BM3, 32.3% were overweight and 25.3% within the boundaries of obesity. The average cholesterol of the group is 4.4mmol.L-l. The Physical activity levels were determined using an activity algorithm developed by the medical aid of the institution (described in detail in the thesis). Results show a low level of physical activity index (7.18 + 3.05) within the sample group. No statistical significance could be found between physical activity levels and medical expenditure, although those who are highly active seemed to have higher expenditure than those who are inactive. / Thesis (M.A. (Human Movement Science))--North-West University, Potchefstroom Campus, 2009.
292

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.
293

Market segmentation of visitors to Aardklop National Arts Festival : a comparison of two methods / Karin Botha

Botha, Karin January 2009 (has links)
Thesis (M.A. (Tourism))--North-West University, Potchefstroom Campus, 2009.
294

Leistungsbedingte und tageszeitliche Einflüsse auf die Herzfrequenz bei Milchkühen

von Buttlar, Britta 15 May 2014 (has links) (PDF)
In der Literatur steht die Herzfrequenz (HF) in engem Zusammenhang mit dem Sauerstoffverbrauch und dem Energieumsatz sowohl von Menschen als auch von verschiedenen Tierarten. In der vorliegenden Arbeit sollte die Hypothese überprüft werden, ob Kühe mit einer hohen Milchleistung und einer hohen Energieaufnahme eine höhere HF infolge eines leistungsabhängig höheren Sauerstoffverbrauchs als niedriglaktierende Tiere haben. So könnte die HF als Indikator für quantitative Veränderungen des Energieumsatzes sowohl für die Einzelkuh als auch auf Bestandsebene genutzt werden. Material und Methoden In vorliegender Untersuchung wurde die HF von 32 Milchkühen der Rasse Deutsche Holstein gemessen. Die Herde erhielt während der Versuche betriebseigenes Grundfutter sowie Maisschrot, Sojaextraktionsschrot und Milchleistungsfutter II. Die tägliche Futter-, Energie- und Proteinaufnahme wurde bestimmt. Die HF-Messung der Kühe erfolgte in zwei Abschnitten. Abschnitt A: Bei 23 Kühen, unterteilt in unterschiedliche Reproduktions- und Leistungsstadien, wurde an fünf aufeinanderfolgenden Tagen die HF erfasst. Abschnitt B: Bei elf Einzeltieren wurde vom 6. bis 101. Laktationstag (LT) die HF in regelmäßigen Abständen alle 14 Tage und an drei aufeinanderfolgenden Tagen gemessen. Den Tieren wurde hierzu ein Polar Equine RSCX800 Science® Gurt mit integrierten Elektroden, ein dazugehöriger Sender und ein Empfänger (Polar Uhr RS800®) angelegt. Die HF wurde einmal pro Minute gespeichert und alle 24 h in das Computerprogramm Polar Pro Trainer Equine Edition 5® übertragen. Folgende weitere Daten wurden erhoben: Stalltemperatur, relative Luftfeuchtigkeit des Stalles, Body Condition Score, Körpermasse, Körperinnentemperatur, tägliche Milchmenge, Milchfett-, Milcheiweiß- und Milchharnstoffgehalt. Ergebnisse Abschnitt A: Die trockenstehenden Kühe hatten eine HF von 83±8 Schlägen/min, die laktierenden Kühe wiesen mit steigender Milchleistung (24,0; 37,1 und 47,7 kg fett- und eiweißkorrigierte Milch) HF-Werte von 84±3, 85±6 und 87±2 Schlägen/min auf. Abschnitt B: In den ersten 100 Tagen der Laktation verhielt sich die HF mit steigendem LT wie folgt: LT 8: 86±9 Schläge/min, LT 22: 86±11 Schläge/min, LT 36: 87±11 Schläge/min, LT 52: 83±10 Schläge/min, LT 66: 83±10 Schläge/min, LT 81: 83±10 Schläge/min, LT 95: 85±8 Schläge/min. Weder in Abhängigkeit von der Leistung (p=0,75) noch in Abhängigkeit vom LT (p=0,81) waren signifikante Unterschiede der HF zu verzeichnen. Die HF der trockenstehenden Kühe variierte im Vergleich zur HF der laktierenden Tiere nicht. Während ihres 24 h-Verlaufs unterlag die HF aller Gruppen einer großen Variation. Es war zu Ruhezeiten der Tiere eine leistungsabhängige Abstufung der HF zu erkennen. Die Umgebungstemperatur hatte in dieser Untersuchung keinen Einfluss auf die HF (r=0,01; p=0,95). Einen signifikanten negativen Zusammenhang gab es zwischen der HF und dem Alter der Tiere (r=-0,44; p<0,01). Dieser führte am 22. LT zu einem signifikanten Unterschied der HF der erstlaktierenden Kühe im Vergleich mit der HF der älteren Tiere (p=0,04). Ein hoher und signifikanter Zusammenhang konnte zwischen der HF und dem Graviditätstag der trockenstehenden Kühe gezeigt werden (r=0,83; p=0,04). Die Tiere, die sich in einer negativen Energiebilanz befanden, neigten in dieser Untersuchung zu einer niedrigeren HF als die Kühe mit einer positiven Energiebilanz. Schlussfolgerung Telemetrische Systeme gewinnen beim Monitoring von Gesundheitsproblemen und Stoffwechselparametern eines Milchviehbestandes zunehmend an Bedeutung. Die HF kann hier jedoch nicht eingesetzt werden, da sie als Indikator für quantitative Veränderungen des Energieumsatzes weder für die Einzelkuh noch auf Bestandsebene geeignet ist. Nach vorliegenden Ergebnissen haben Kühe mit einer höheren Milchleistung und einer höheren Energieaufnahme keine höhere HF. / Previous studies have revealed a close relationship between heart rate (HR) and energy expenditure in humans and some other animal species. The present study examined whether dairy cows with a higher milk yield and greater energy intake have a higher HR due to greater oxygen consumption. HR might serve as an indicator of quantitative changes of energy expenditure in an individual or in a group of dairy cows at the herd level. Materials and methods The HRs of 32 dairy cows of the German Holstein breed were measured. The cows received forages and fresh beet pulp in combination with ground corn, soybean extracts, and a concentrate during the study. Daily feed, energy, and protein intake were determined. HR measurement was performed in two blocks. In Block A, cows were divided into four groups that differed in reproductive state and milk yield, and HR was measured for five consecutive days. In Block B, every 14 days, HR was recorded for three consecutive days in 11 cows from 6 to 101 days in milk (DIM). A Polar Equine RSCX800 Science® belt with integrated electrodes, a transmitter, and a receiver (Polar RS800®) was applied to the animals. HR was recorded once a minute and transferred every 24 h to the software Polar Pro Trainer Equine Edition 5®. The following data were also collected: stable temperature, stable relative humidity, body condition score, body weight, body temperature, daily milk yield, milk fat, milk protein, and milk urea. Results In Block A, dry cows had a HR of 83±8 beats/min, and lactating cows with increasing milk yield (24.0, 37.1, and 47.7 kg energy-corrected milk) showed HRs of 84±3, 85±6, and 87±2 beats/min, respectively. In Block B, the HRs were as follows: 8 DIM: 86±9 beats/min, 22 DIM: 86±11 beats/min, 36 DIM: 87±11 beats/min, 52 DIM: 83±10 beats/min, 66 DIM: 83±10 beats/min, 81 DIM: 83±10 beats/min, 95 DIM: 85±8 beats/min. There was not a significant difference in the HR according to milk yield (p=0.75) or days of lactation (p=0.81). The HR of dry cows did not differ from that of lactating cows. There was a large variation of HR in all groups during the day. During resting times, HR of the high-yielding cows tended to be higher and HR of the dry cows tended to be lower than the HR of the other groups. The ambient temperature had no influence on HR in this study (r=0.01, p=0.95). There was a significant negative correlation between HR and a cow’s age (r=–0.44, p<0.01). The HR of primiparous cows was higher than that of multiparous cows, but the difference was only significant when cows were 22 DIM (p=0.04). A high and significant correlation was found between HR and pregnancy status (r=0.83, p=0.04), with HR increasing during pregnancy. Dairy cows with a negative energy balance tended to have a lower HR than cows with a positive energy balance. Conclusion Telemetry systems have become increasingly important in monitoring health problems and the parameters of energy metabolism in dairy herds. The results of this study indicate that HR cannot be used as a monitoring tool, because HR is not a suitable indicator of quantitative changes of energy expenditure either at the individual or herd level. According to the results of this study, dairy cows with a higher milk yield and greater energy uptake do not have a higher HR.
295

A Bbiomechanical Assessment of Active Video Gaming in Children with Cerebral Palsy Detailing Energy Expenditure, Muscle Activations, and Upper Limb Kinematics

Irwin, Jennifer D. 08 December 2011 (has links)
This thesis evaluated energy levels, muscle activity, and upper limb kinematics during AVG play in children with cerebral palsy (CP). For context, a systematic review was conducted, which found that AVGs elicited light to moderate physical activity in typically developing children. In children with CP, moderate levels of physical activity were achieved for Dance Dance Revolution and Wii Boxing, while light levels of physical activity were achieved for Wii Bowling and Wii Tennis. Muscle activity was highest during Wii Boxing, but remained below the maximum voluntary effort for all games and muscles. Angular velocities and accelerations were significantly larger in the dominant limb compared to the hemiplegic limb. When children played against a real opponent, dominant arm activity increased, while hemiplegic arm activity decreased. The results of this thesis indicate that AVGs may be an enjoyable and relatively safe option for children with CP to attain moderate physical activity.
296

A Bbiomechanical Assessment of Active Video Gaming in Children with Cerebral Palsy Detailing Energy Expenditure, Muscle Activations, and Upper Limb Kinematics

Irwin, Jennifer D. 08 December 2011 (has links)
This thesis evaluated energy levels, muscle activity, and upper limb kinematics during AVG play in children with cerebral palsy (CP). For context, a systematic review was conducted, which found that AVGs elicited light to moderate physical activity in typically developing children. In children with CP, moderate levels of physical activity were achieved for Dance Dance Revolution and Wii Boxing, while light levels of physical activity were achieved for Wii Bowling and Wii Tennis. Muscle activity was highest during Wii Boxing, but remained below the maximum voluntary effort for all games and muscles. Angular velocities and accelerations were significantly larger in the dominant limb compared to the hemiplegic limb. When children played against a real opponent, dominant arm activity increased, while hemiplegic arm activity decreased. The results of this thesis indicate that AVGs may be an enjoyable and relatively safe option for children with CP to attain moderate physical activity.
297

Examining the Effects of Weight Loss on Energy Expenditure in Humans

Schwartz, Alexander 30 November 2011 (has links)
Being able to effectively match energy intake to energy expenditure (EE) is an important aspect in preventing weight re-gain in the post-obese. Although it is generally agreed upon that resting EE decreases concomitantly with weight loss, there is no set standard comparing the deviations with differing weight loss protocols and additionally, controversy remains as to whether this decrease is greater than can predicted. In order to address these issues 2977 subjects were analyzed using a systematic review and the differences of both the protocol and length of various interventions in addition to sex were compared. Next, data was selected from this systematic review and 815 subjects were analyzed for weight loss-induced changes in resting EE, FM and FFM. Another subgroup of studies (n = 1450) was analyzed and compared against the Harris-Benedict prediction equation to determine whether the changes in resting EE were greater than what was expected. Finally, in order to determine which factors may be involved in regulating changes in resting EE during weight loss, a secondary analysis was performed on 28 post-menopausal women (age= 50.4 ± 2.0 yrs; BMI= 32.4 ± 5.2 kg/m²) who were submitted to a 6-month caloric restriction. Body composition (DXA), resting EE (indirect calorimetry), physical activity EE (PAEE) and total EE (TEE) (doubly-labelled water) were measured before and after the 6 month weight loss. Blood samples were collected before and after to measure leptin and peptide YY. The results indicate that there was indeed a depression in resting EE during weight loss regardless of the type of intervention utilized. Furthermore, these findings suggest that the changes could not fully be explained by changes of FM and FFM alone and that leptin may be an important contributor to the changes of resting EE during weight loss.
298

Analysis of Healthcare Coverage Using Data Mining Techniques

Tekieh, Mohammad Hossein 12 January 2012 (has links)
This study explores healthcare coverage disparity using a quantitative analysis on a large dataset from the United States. One of the objectives is to build supervised models including decision tree and neural network to study the efficient factors in healthcare coverage. We also discover groups of people with health coverage problems and inconsistencies by employing unsupervised modeling including K-Means clustering algorithm. Our modeling is based on the dataset retrieved from Medical Expenditure Panel Survey with 98,175 records in the original dataset. After pre-processing the data, including binning, cleaning, dealing with missing values, and balancing, it contains 26,932 records and 23 variables. We build 50 classification models in IBM SPSS Modeler employing decision tree and neural networks. The accuracy of the models varies between 76% and 81%. The models can predict the healthcare coverage for a new sample based on its significant attributes. We demonstrate that the decision tree models provide higher accuracy that the models based on neural networks. Also, having extensively analyzed the results, we discover the most efficient factors in healthcare coverage to be: access to care, age, poverty level of family, and race/ethnicity.
299

Endogenous Growth Testing In The European Union And Developing Countries: Taxation, Public Expenditure And Growth

Derin, Pinar 01 January 2003 (has links) (PDF)
In endogenous growth models, in contrast to the neoclassical growth models, government expenditure and taxation have an effect on the long run growth rate. In this thesis I examine whether the empirical evidence support the predictions of endogenous growth models or the neoclassical growth models in relation to fiscal policy. For this purpose I use panel data for fifteen European Union (EU) member and thirty-three developing countries between the years 1970 and 1999. I specifically test the following two propositions. The first proposition states that distortionary taxation decreases growth while non-distortionary taxation does not. The second, states that productive government expenditure increases growth while non-productive expenditure does not. The empirical results are quite different between European Union countries and developing countries. The results do not support endogenous growth especially for developing countries.
300

Emergy analysis to assess ecological sustainability : strengths and weaknesses /

Björklund, Johanna, January 2000 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

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