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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.
91

The Influence of Weight Status on the Link between Television Viewing and Food Intake in Children

Borghese, Michael M. 08 May 2014 (has links)
Recent research suggests that sedentary behaviours have detrimental effects on the health and well-being of children, including effects on obesity. Specifically, television viewing is consistently associated with childhood obesity. Two explanations have been proposed: 1) reduced energy expenditure, and 2) increased food intake. However, it has been suggested that the association between television viewing and childhood obesity may be better explained by an increase in energy intake than by a reduction in energy expenditure. To date, children of different weight status have not been compared in their dietary patterns in front of the television, and it is not known if total sedentary time is linked with food intake in children. The objectives of this thesis are: 1) to determine if obese children consume food more frequently while watching television than normal weight children, and 2) to examine which of television viewing or total sedentary time better predicts dietary patterns in children. Overall, our results re-affirm the notion that television viewing is associated with obesity, although physical activity plays a role in this association. Also, children who are obese consume fast food and fruits/vegetables more frequently during television watching than normal weight children. Furthermore, television viewing appears to be a better predictor of dietary patterns in children than overall sedentary time. Globally, these results provide evidence for the deleterious effects of television viewing on children’s dietary patterns and justification for future intervention studies designed to reduce television viewing in children with obesity.
92

Leptin and cardiovascular function in African and Caucasian men and women : the SABPA study / Pieterse, C.

Pieterse, Chiné January 2011 (has links)
Forensiese assesseringstegnieke wat tydens ondersoeke na kinder seksuele misbruik benut word, het in n hoë mate mettertyd ontwikkel. Navorsing het n waardevolle bydrae gelewer tot effektiewe en geskikte assesseringstegnieke. Verdere navorsing is egter nodig om die bestaande tegnieke te ondersoek. Die persoon wat by forensiese assesserings betrokke is, kan baat vind by die leiding wat navorsing bied. Op grond hiervan het die navorser ondersoek ingestel na die forensiese assesseringstegnieke wat tans in die praktyk deur forensiese maatskaplike werkers benut word. Gedurende die ondersoek is verskeie tegnieke wat tydens forensiese assesseringsonderhoude benut word, geïdentifiseer en bespreek. Die sistematiese aanrakingseksplorasie is vir die doel van hierdie studie deur die navorser uitgesonder. Hierdie tegniek is aan die hand van n gevallestudie bestudeer en bespreek. Ondersoek is ook ingestel na die menings van maatskaplike werkers wat in die forensiese veld werksaam is, asook dié van justisie–amptenare, onder wie landdroste en staatsaanklaers, wat in die hof vir seksuele misdrywe werksaam is, ten opsigte van die benutting van die sistematiese aanrakingseksplorasie. Die justisie–amptenare was aanvanklik nie vertroud met die tegniek nie. Nadat literatuur vir bestudering aan hulle beskikbaar gestel is, is vasgestel dat hulle ontvanklik is vir en positief staan teenoor die benutting van die sistematiese aanrakingseksplorasie. Die ondersoek het ten doel gehad: * Om deur middel van n literatuurstudie die forensiese assesseringstegnieke wat tans in die praktyk benut word, te identifiseer en te bespreek; en * Om die sistematiese aanrakingseksplorasietegniek aan die hand van n literatuurstudie en empiriese navorsing te evalueer. Samevattend kan gestel word dat die tegnieke, soos in hierdie navorsing bespreek, deel behoort uit te maak van die protokol van die professionele persoon wat die seksueel misbruikte kind assesseer. Hierdie navorsing het bevind dat die sistematiese aanrakingseksplorasie n waardevolle forensiese assesseringstegniek is ten opsigte van die seksueel misbruikte kind. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2012.
93

Long-term consequences of anterior cruciate ligament injury : knee function, physical activity level, physical capacity and movement pattern

Tengman, Eva January 2014 (has links)
Knee function after more than 20 years post injury is rarely described and none of the few follow-up studies have evaluated functional performance tasks. This thesis investigated self-reported knee function, physical activity level, physical capacity and movement pattern in the long-term perspective (on average 23 years) in persons who had suffered a unilateral ACL injury, treated either with physiotherapy in combination with surgery (ACLR, n=33) or physiotherapy alone (ACLPT, n=37) and compared to age-and-gender matched controls (n=33).  This thesis shows that regardless of treatment, there are significant negative long-term consequences on self-reported knee function and physical activity more than 20 years after injury. In comparison to the controls, the ACL-groups (ACLR and ACLPT) had lower knee function as measured by the Lysholm score and the Knee injury and Osteoarthritis Outcome Score (KOOS). The persons with an ACL injury also had a lower knee-specific physical activity level (Tegner activity scale), while no differences were seen in general physical activity level (International Physical Activity Questionnaire, IPAQ) compared to healthy controls. Regarding physical capacity, both ACL groups showed inferior jump capacity in the injured leg compared to the non-injured leg. However, compared to controls the ACL-injured had a relatively good jump performance. Knee extension peak torque, concentric and eccentric, was also lower for the injured leg compared to the non-injured leg for both ACLR and ACLPT. In addition, the ACLPT group showed reduced eccentric knee flexion torque of the injured leg. The non-injured leg, on the other hand, showed almost equal jump capacity and strength as controls. Balance in single-limb stance (30s) was inferior in persons who had an ACL injury. This was true for both the injured and non-injured leg and regardless of treatment. Movement pattern during the one-leg hop was analysed by a set of kinematic variables consisting of knee angles (flexion, abduction, rotation) and Centre of Mass (CoM) placement in relation to the knee and ankle joints. Both ACLR and ACLPT displayed movement pattern asymmetries between injured and non-injured legs. In comparison to controls, the ACLR group had a similar movement pattern with the exception of larger external knee rotation at Initial contact and less maximum internal rotation during the Landing. ACLPT showed several differences compared to controls both regarding knee angles and CoM placement. The ACL-injured persons with no-or-low knee osteoarthritis (OA) had better knee function as reflected by higher scores on Lysholm and KOOS subscale ‘symptom’ compared to those with moderate-to-high OA. The degree of OA had no influence on reported physical activity level, jump capacity, peak torque or the kinematic variables.  In conclusion, this thesis indicates that persons with a unilateral ACL injury, regardless of treatment, have some negative long-term consequences e.g. self-reported knee function, knee-specific activity level, strength and balance deficits, when compared to age-and-gender matched controls. The results, however, also indicate that the ACL-injured can manage reasonably well in some jumps and general activity level but have an inferior performance in more knee-demanding tasks. The ACLR group had similar movement pattern with the exception of knee rotation, indicating that a reconstruction may restore the knee biomechanics to some extent. The ACLPT group on the other hand, seem to use compensatory movement strategies showing several differences compared to controls.
94

The Relationship Between Alcohol Intake and Body Fat Percentage in Adult University Employees

Beardsley, Jessica 10 June 2014 (has links)
Background: Factors that contribute to body fat and adiposity include energy consumption, macronutrient intake, and physical activity. Alcohol not only contributes to total energy consumed but also influences metabolic pathways that may alter fat oxidation and storage. Alcohol provides 7.1 kilocalories per gram (kcal/g) and makes up 6-10% of the daily caloric intake of adults in the United States. Cross-sectional studies have shown that increased alcohol intake is associated with higher body mass index (BMI), especially in men. Other studies suggest that there is a “U” shaped association whereby non-drinkers and heavy drinkers have a higher BMI and waist-to-hip ratio (WHR) then low to moderate drinkers. While many previous studies evaluate alcohol based on the average consumption (g/day), there is increasing evidence that it is the pattern of alcohol consumption (ie. frequency) that influences body composition. The purpose of this study is to evaluate the effect of the frequency of wine, beer, and liquor consumption on body fat percent (BF%) and WHR in a population of university faculty and staff. Methods: The Center for Health Discovery and Well Being (CHDWB) cohort trial is being conducted at Emory University in Atlanta, GA. Recruitment of faculty and staff for the study began in 2007. Demographic, reported dietary intake including wine, beer, and liquor consumption, and anthropometric data including weight, height, BF%, and waist circumference are collected at baseline and annually thereafter. We used linear regression models to determine the effect of frequency and quantity of wine, beer, and liquor consumption on BF% while controlling for age and the effects of the other types of alcohol. We applied the Kruskal-Wallis test to determine if the median BF% and waist-hip ratio (WHR) was significantly different for those that reported at different five different frequencies (several times a year to 5-7 days a week). Results: Baseline visits have been conducted on 700 participants. Their median age was 51 years (66% female). Median weight was 76.9 kg (range, 65.3 - 90.5 kg) and mean BMI was 27.9 + 6.4 kg/m2. A significant negative relationship was observed between frequency of beer consumption and BF% in women (p Conclusions: The frequency of wine intake consumed by university employees and staff independently predicted BF% and BMI. Greater frequency of wine consumption was associated with lower BF%.
95

Goodness-of-Fit for Length-Biased Survival Data with Right-Censoring

Younger, Jaime 02 February 2012 (has links)
Cross-sectional surveys are often used in epidemiological studies to identify subjects with a disease. When estimating the survival function from onset of disease, this sampling mechanism introduces bias, which must be accounted for. If the onset times of the disease are assumed to be coming from a stationary Poisson process, this bias, which is caused by the sampling of prevalent rather than incident cases, is termed length-bias. A one-sample Kolomogorov-Smirnov type of goodness-of-fit test for right-censored length-biased data is proposed and investigated with Weibull, log-normal and log-logistic models. Algorithms detailing how to efficiently generate right-censored length-biased survival data of these parametric forms are given. Simulation is employed to assess the effects of sample size and censoring on the power of the test. Finally, the test is used to evaluate the goodness-of-fit using length-biased survival data of patients with dementia from the Canadian Study of Health and Aging.
96

Deformation behaviour of diamond-like carbon coatings on silicon substrates

Haq, Ayesha Jabeen, Materials Science & Engineering, Faculty of Science, UNSW January 2008 (has links)
The deformation mechanisms operating in diamond-like carbon (DLC) coatings on (100) and (111) Si, has been investigated. The effect of coating thickness, indenter geometry, substrate orientation and deposition technique on the deformation of DLC coatings and the underlying substrate was studied by undertaking nanoindentation followed by subsurface microstructural characterization. Uncoated (111) Si was also investigated for comparison. The observed microstructural features were correlated to the indentation response of the coatings and compared with simulation studies, as well as observations on uncoated Si. In uncoated (111) Si, phase transformation was found to be responsible for the discontinuities in the load-displacement curves, similar to (100) Si. However, slip was activated on {311} planes instead of on {111} planes. Moreover, the density of defects was also significantly lower and their distribution asymmetric. The coatings were adherent, uniformly thick and completely amorphous. The load-displacement curves displayed several pop-ins and a pop-out, the indentation loads for the first pop-in and the pop-out depending primarily on the thickness of the coating. The coatings exhibited localized compressive deformation in the direction of loading without any through-thickness cracks. The extent of this localized deformation increased with indentation load. Hardness and thickness of the coatings and the geometry of the indenter influenced the magnitude of compressive strains. Harder and thinner coatings and a blunt indenter exhibited the minimum degree of deformation. Densification by rearrangement of molecules has been suggested as the mechanism responsible for plastic compression. At indentation loads corresponding to the first pop-in, (100) and (111) silicon substrates initially deformed by <111> and <311> slip respectively. Higher indentation loads caused phase transformation. Therefore, unlike in uncoated Si, dislocation nucleation in the Si substrate has been proposed as the mode responsible for the first pop-in. Subsequent pop-ins were attributed to further deformation by slip and twinning, phase transformation and extensive cracking (median and secondary cracks) of the substrate. The pop-out, however, was ascribed to phase transformation. Extensive deformation in the substrate, parallel to the interface, is attributed to the wider distribution of the stress brought about by the DLC coating. Good correlation was obtained between the nanoindentation response, microstructural features and simulation studies.
97

Accruals: signalling or misleading? Evidence from New Zealand

Koerniadi, Hardjo Unknown Date (has links)
Studies on earnings management usually hypothesise that managers manage accruals opportunistically. Few studies however, argue that managers can also use accruals to improve the value relevance of reported earnings to help investors better assess the firm's operating performance. While substantial evidence on managers' opportunistic behaviour on accruals has been documented in the literature, empirical evidence on the informativeness of accruals is scarce and inconclusive. The purpose of this thesis is to examine whether managers use accruals to communicate private information regarding the firm's operating performance, or as reported in the literature, use them for their own benefit. This thesis finds that on average, firms reporting high earnings accompanied by high accruals have significantly negative subsequent period stock returns suggesting that these firms manage their accounting earnings. Focusing on stock dividend issues as an incentive to opportunistically increase accruals, the results are found to be consistent with the earnings management hypothesis. Stock dividend issuing firms are reported to significantly increase accruals in the issue year followed by poor earnings and stock price performances in the subsequent year. Moreover, discretionary accruals of the issuing firms are negatively correlated with both future earnings and abnormal stock returns. This evidence attempts to complement the earnings management literature. The analysis on the incentive to decrease accruals related to share repurchases, however, does not provide sufficient evidence to suggest that managers use their discretion to decrease accruals. To investigate the hypothesis that managers use accruals to convey information regarding their firm's future profitability, this thesis employs the contemporaneous earnings and dividend announcements as the research setting. This choice was made to increase the likelihood of detecting the use of accruals as private information communication while simultaneously mitigating the likelihood of the opportunistic income smoothing hypothesis to explain the results. The evidence strongly indicates that managers use both accruals and dividend increases as their private information communication regarding their firm's future profitability. Dividend increasing firms report positive accruals which are positively correlated with future profitability. This finding contributes to the literature by providing evidence on the accrual signalling hypothesis. Overall, the results of this thesis suggest that, depending on the incentives, managers can use the discretion accorded under the Generally Accepted Accounting Principles (GAAP) in estimating accounting accrual, either to manage accruals opportunistically or to help investors better assess the firms' operating performance.
98

Muscle power after stroke

Stavric, Verna A January 2007 (has links)
Stroke is the leading cause of disability worldwide. It often leads to mobility limitations resulting from deficits in muscle performance. While reduced muscle strength and rate of force production have been reported, little is known about the power generating capability of people after stroke and its relationship to mobility. Research in other populations has found that measures of muscle power may have a greater association with activity performance than do measures of muscle force alone. Consequently, in an attempt to optimise power, investigators have focused on identifying ideal parameters within which to train for power. One such parameter is the identification of the loading level at which maximal power is generated. Literature reporting optimal loads from both young athletic and healthy older populations has yielded mixed results, making the applicability to a hemiparetic population difficult. The purpose of this study was to investigate muscle power performance at differing loads and to determine at what load muscle power is best elicited in hemiparetic and age and gender matched control groups. A secondary aim was to ascertain whether there is a relationship between the muscle power values obtained and activities such as gait, stair climbing and standing from a chair. Twenty nine hemiparetic volunteers and twenty nine age and gender matched controls were evaluated. Involved and uninvolved legs of the stroke group and a comparison leg of the control group underwent testing. Leg press muscle power was measured using a modified supine leg press machine at 30%, 50% and 70% of a one-repetition maximum (1-RM) load. Participants were positioned on the leg press machine and asked to push, with a single leg, as hard and as fast as they could. Data was collected via a mounted force platform and a linear transducer connected to a platform on which the participants lay. From these, power was able to be calculated. The activities were timed while being performed as fast as possible. The results showed that peak muscle power values differed significantly between the involved, uninvolved and control legs. Peak leg power in all three leg groups was greatest when pushing against a load of 30% of 1-RM. Involved leg peak power tested at 30% of 1-RM (Mean:240; SD:145 W) was significantly lower (p<0.05) than the uninvolved leg (Mean:506; SD:243 W). Both the involved and uninvolved legs generated significantly lower peak power (p<0.05) than the control leg (Mean:757; SD:292 W). Correlations were found between the involved leg peak power and gait speed and involved leg peak power and stair climbing (r=0.6-0.7, p<0.05). No correlation was found between paretic leg peak power and chair stands. The control group leg peak power demonstrated significant associations with the performance of all three activities.In summary, there were significant differences between the involved and the uninvolved leg in power production after stroke. As well, there are significant differences between the uninvolved leg and the leg of those not affected by stroke. Power was related to a number of activities.
99

A population perspective on obesity prevention : lessons learned from Sweden and the U.S. /

Nafziger, Anne, January 2006 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2006. / Härtill 5 uppsatser.
100

Gender differences in cardiovascular risk indicators and cardiovascular disease among veterans with PTSD

Frazier, Elizabeth C. January 2008 (has links) (PDF)
Thesis (Ph. D.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed Feb. 12, 2009). Includes bibliographical references (p. 35-43).

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