• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 612
  • 384
  • 60
  • 54
  • 54
  • 23
  • 20
  • 9
  • 8
  • 4
  • 4
  • 3
  • 2
  • 2
  • 2
  • Tagged with
  • 1510
  • 451
  • 314
  • 226
  • 200
  • 197
  • 190
  • 174
  • 150
  • 126
  • 124
  • 120
  • 111
  • 106
  • 98
  • 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.
531

Experimental Exposure to Ideal-Body Media Images: Restrained Eaters' Self-Evaluation, Mood and Food Intake

Boyce, Jessica Anne January 2012 (has links)
The mass media project a thin “ideal” female body type (ideal-body media; IBM) onto young women. Sociocultural theorists propose that, through processes of internalisation and social comparison, IBM-exposure promotes negative body satisfaction and unhealthy eating behaviour. In three experiments, I investigated how IBM-exposure affected restrained eaters. Restrained eaters are women who are trying to lose weight by attempting to restrict their food intake. Previous researchers have found that restrained eaters perceive and process body-related information more readily than others do. The literature surrounding restrained eaters’ IBM-related self-evaluations and food intake is inconsistent. Some researchers have found restrained eaters to report positive self-evaluative effects and others have not. Furthermore, the majority of researchers report that viewing IBM triggers restrained eaters’ eating. However, this effect is not always replicated and this might be because restrained eaters have been identified with different restraint scales. To test this idea, I used two conceptually different dietary restraint scales throughout the current experiments: the concern for dieting subscale of the Restraint Scale (RS-CD) and the Dietary Intent Scale (DIS). Furthermore, because some researchers have argued that participants within previous (non-restraint) studies reported negative IBM-effects because they thought that they were meant to be negatively affected (i.e., demand characteristics), reducing these demands was a focus throughout the current experiments. In Study 1, demand characteristics were minimised by employing implicit outcome measures and by incorporating a two-study pre-text to separate the experimental manipulation from the explicitly measured dependent variables. Under the guise of a hunger and memory study, restrained and unrestrained eaters (N = 107) were required to concentrate on a slideshow of IBM- or Control-images for 2-minutes and complete an associated memory test (i.e., advertent attention). Restrained eaters (RS-CD and DIS) exposed to IBM reported negative effects (e.g., mood). However, IBM-exposure did not trigger their food intake in an unrelated taste test with M&Ms. I interpreted these findings alongside control theory. This is the theory that goal-related negative affect encourages increased goal-performance. I reasoned that paying advertent attention to the IBM caused goal-related negative affect, which triggered goal effort (i.e., dietary restraint). This theory was further tested in Study 2. The same manipulation was used in Study 2 (N = 268), which was touted as a study about participants’ personality and task performance. Here, I aimed to test restrained eaters’ implicit approach and avoidance tendencies toward diet and food stimuli. Therefore, a joystick lexical decision task (LDT) was used instead of a taste test. Restrained eaters’ self-evaluations (e.g., self-esteem) were not significantly affected by being in different experimental conditions. However, restrained eaters (RS-CD) in the IBM-condition avoided high-calorie food words during the LDT significantly faster than other participants did. These results (Studies 1 and 2) differed from previous research. This difference was attributed to the high level of advertent attention participants paid to the IBM in my experiments. Therefore, in Study 3, I manipulated participants’ attention levels. Participants (N = 171) were made to believe that the experimental slideshow and LDT were part of a task performance study. Although participants who were assigned to the Inadvertent- and Advertent-Attention conditions were exposed to the same slideshow (IBM- or Neutral-images), the experimenter did not ask participants in the Inadvertent-condition to focus on the slideshow. After this experimental manipulation, participants completed the joystick LDT. Subsequently, they completed a second unrelated study about personality and the five human senses (e.g., taste, touch, etcetera). All participants were randomly assigned to the taste-condition and completed a taste test. Inconsistent with my previous results, I did not obtain significant self-evaluation or LDT results. Furthermore, restrained eaters (RS-CD) who paid advertent attention to the IBM consumed more food than others consumed during the taste test. In comparison, restrained eaters were buffered from this effect if they had paid inadvertent attention to the IBM-images. When comparing these (nonsignificant and significant) results with previous research, it seems that restrained eaters’ IBM-responses are highly specific to environmental and/or experimental settings. I developed a preliminary theory to predict restrained eaters’ behaviour. This theory takes into account participants’ restraint status, restraint success, IBM-related attention and their eating-related attention.
532

COMPARISON OF NUTRITIONAL INTAKE OF HOME SCHOOL CHILDREN AND PUBLIC SCHOOL CHILDREN: A COMPARISON STUDY

Perry, Stephen D. 01 January 2008 (has links)
Purpose: To compare selected food /nutrient consumption between families that educate their children at home with those that educate their children in the public school system. Methods: The study sample included 112 children aged 7-11 years in Fayette Co Kentucky. The children were divided into groups according type of education. There were 65 home-schooled children and 47 children who attend public school. Subjects recorded their dietary intake for one week. The data were analyzed using Nutrition Data Software for Research (2006). Comparisons were made for the intake of selected nutrients using two tailed independent sample t-tests. Results: The public school students had a lower intake of Total Energy (calories, P=0.01), Total Fat (P= 0.02), Total Carbohydrate (P= 0.04), Total Protein (P= 0.004) and Total Dietary Fiber (P= 0.02) and selenium (P= 0.000) than did their home-schooled counterparts. Conclusion: Interpretation of the statistical analysis indicates that differences for consumption exist between the groups. The results of this study indicate that the public school children consumed less fat, protein, carbohydrates and sucrose than did their home school cohort.
533

Impact of direct-fed microbials on nutrient utilization in beef cattle

Kenney, Nicole 01 January 2013 (has links)
The impact of lactate producing direct-fed microbial (DFM) on growth performance and rumen fermentation in beef cattle was explored in four studies. Experiment 1 studied the interaction between DFM and degradable intake protein (DIP) supply in receiving cattle. No differences (P≥0.06) in intake, morbidity, or immune response were observed; however, during the first 28 d gain and efficiency responses to DFM were dependent on DIP (DIP×DFM P≤0.05). Experiment 2 showed that in vitro gas production and select endpoint metabolites differed (P≤0.04) with DFM application. Experiment 3 compared lactate producing DFM to a lactate producing/utilizing DFM in finishing cattle. No differences (P≥0.14) in intake, gain, efficiency, or carcass characteristics were observed between control and lactate DFM; however, gain and growth efficiency differed (P≤0.05) between the lactate producing and lactate producing/utilizing DFM during the later portions of feeding. Experiment 4 studied the impact of DFM on ruminal fermentation, lactate utilization, and total tract digestibility. Ruminal pH and molar proportions of acetate were increased (P≤0.05) with DFM; however, lactate utilization and total tract digestibility did not differ (P≥0.33). The studies suggest that DFM improve growth performance during receiving and responses are at least partly mediated through differences in ruminal fermentation.
534

MONITORING DAIRY COW FEED INTAKE USING MACHINE VISION

Shelley, Anthony N. 01 January 2013 (has links)
The health and productive output of dairy cows can be closely correlated to individual cow feed intake. Being able to monitor feed intake on a daily basis is beneficial dairy farm management. Each cow can be addressed individually with minimal time required from those working with the animals. This is essential as time management is closely tied to resource management in a dairy operation. Anything that can save time and resources and increase profitability and herd health is a paramount advantage in dairy farming. This study examined the use of machine vision structured light illumination three-dimensional scanning of cow feed to determine the volume and weight of feed in a bin before and after feeding dairy cow. Calibration and control tests were conducted to determine the effectiveness and capability of implementing such a machine vision feed scanning system. Such a system is ideal as it does not obstruct workflow or cow feeding behavior. This is an improvement over existing systems as the system in this research study can be implemented into existing farm operations with minimal effort and costs.
535

Celiac Disease: a Gluten Free Diet and Diet Quality

Stauble, Taylor M 01 January 2013 (has links)
The media has highlighted a proposed link between a gluten free diet (GFD) and weight loss. However, research related to weight gain and a GFD for persons with celiac disease (CD) has shown the opposite effect. A GFD is the only known treatment for persons with CD. If a patient with CD consumes a diet high in GF processed foods, weight management may be difficult to achieve. Participants with self-reported CD completed a modified GF food frequency questionnaire (FFQ) to assess typical dietary consumption of whole grains, sweets, fruits, vegetables and regular soda. Additionally, body mass index (BMI) and exercise were assessed. The results of this study found that whole grain, fruit and vegetable intakes were low among celiac patients. Additionally, BMI was on the high end of the normal weight range. The results of this study indicate that a greater emphasis should be placed on nutritional quality when counseling patients with CD. Registered dietitians should focus their diet counseling sessions with CD patients on a nutritious naturally GF diet in order to better manage weight.
536

THE EFFECT OF A NUTRITION EDUCATION PROGRAM ON NUTRITION KNOWLEDGE, DIETARY INTAKE, BODY COMPOSITION AND PERCEIVED SPORT PERFORMANCE AMONG HIGH SCHOOL ATHLETES

Schwartz, Aaron Kyle 01 January 2014 (has links)
Nutrition knowledge, dietary intake, body composition and perceived sport performance were measured before and after an eight week nutrition intervention. The sample consisted of eleven male high school football athletes aged 14-18 years old. Baseline nutrition knowledge was higher than anticipated but fruit and vegetable intake was low. As a result of the nutrition intervention, vegetable intake improved from 0.94 servings per day to 2.02 servings per day (p=0.02). Of the eleven subjects in the study, eleven conceded to both performing and feeling better as a result of the nutrition intervention. The present study suggests that a nutrition intervention can improve dietary intake and perceived sport performance among adolescent athletes.
537

Aspects of institutional care of patients with dementia

Sandman, Per-Olof January 1986 (has links)
The aim of the present study was to investigate all long-term institutions in the county of Västerbotten, Northern Sweden, to give a detailed description of the institutionalized population with respect to motor functions, vision, hearing, speech, ADL-functions, prevalence of psychiatric symptoms and behavioral disturbances, staff work load, use of psychoactive drugs and prevalence of dementia. Another aim was to select some specific 'problem areas' in the nursing care of demented patients for further descriptive and interventional studies. For this reason, morning care procedure (hygiene, dressing), meal behavior (eating, communication), nutrition, constipation and relocation between institutions were selected. The results of the study have been reported in six papers summarized below: I.The study has shown that the proportion of demented patients is increasing in longterm institutions in Sweden. Furthermore, demented patients were shown to be more impaired in all rated functioning abilities and exhibited more psychiatric symptoms and behavioral symptoms. A high proportion of the demented probands were also prescribed psychoactive drugs, i.e. neuroleptics. II. Five patients with Alzheimer-type dementia were monitored during morning care. A 12-step classification system was developed to be used as a guide to understand and determine abilities essential for performance of morning care for demented patients. The quantitative assessment showed that none of the patients were able to manage morning care independently, but there was a wide variation in their highest level of performance. III. Five patients with Alzheimer-type dementia were observed (video taped) during their meals in a changed meal milieu and with new meal routines. When the patients ate without staff participation, the two least demented patients became 'caregivers'. When two mental nurses joined the group, first in civil clothes and then in white uniforms, the patients dropped their roles as helpers. The patients were able to compose complete meals in 0-79 per cent of the meals. The conversation during the meals could be characterized as incomplete, with short sentences and a lot of breaks. Sixty-three per cent of all utterances were about food and eating and almost all conversation concerned the present time. IV. Thirty-three psychogeriatric patients, with severe constipation were given a high- bran bread instead of their accustomed laxatives. During the high-bran treatment period, the number of bowel evacuations and the volume of faeces increased. The total laxative consumption decreased by 93 per cent. V. Nutritional status and dietary intake were studied in a sample of severely demented, institutionalized patients. Energy and /or protein malnutrition was found in 50 per cent of the patients. The mean energy intake was 2059 kcal. Malnourished patients had had four times as many infectious periods during their hospital stay as patients without malnutrition. Thirty-nine of 44 patients lost weight during their hospital stay. VI. Thirty-three psychogeriatric patients were followed for 36 weeks after relocation from a mental hospital to two newly built nursing homes. An intensive pre-relocation program was performed. No negative effects of the relocation were found. On the contrary, the relocated group improved their ADL-functions after the transfer. Based upon the above cited studies, a model for nursing care of demented patients is presented. / <p>S. 1-45: sammanfattning, s. 46-192: 6 uppsatser</p> / digitalisering@umu
538

Creation and destruction of in-cylinder flows : Large eddy simulations of the intake and the compression strokes

Söder, Martin January 2015 (has links)
The aim of this thesis is to increase engine efficiency by studying the flow structures created in an engine cylinder during the intake phase and the effect of the subsequent compression. The invention of the combustion engine has enabled three centuries of economic growth fueled by energy stored as hydrocarbons. However, during the latter part of the twentieth century negative consequences on health and environment of the combustion engine were observed. In order to reduce emissions without increasing fuel consumption, improved knowledge of all physical processes occurring in the engine are necessary. The aim of this thesis is to increase the understanding of the flow prior to combustion, which can lead to reduced engine emissions and fuel consumption. Intake flow structures are studied using large eddy simulations and experiments on a steady swirl test rig. Flow acceleration was observed to reduce the swirl coefficient, and higher swirl coefficient was found during valve closing as compared to during valve opening. This implies that the rotation is stronger during the later part of the intake then what has been previously assumed. In addition, the computations show that the volume above the valves has a profound effect on the swirl created during the intake. To take this into account a novel way of calculating the swirl number was suggested. This approach gives a lower swirl number as compared to the commonly used Thien methodology. The effects of compression are studied using simulations of predefined flow structures undergoing compression. The peak turbulence levels were found to be increasing with tumble number and decreasing with swirl. It was noted that compression increased the turbulent fluctuations in the cylinder axis leading to anisotropic turbulence and that a small tilt angle was observed to have a significant effect on swirl homogeneity at top dead center.  In this thesis, a new methodology was proposed and validated for calculation of in-cylinder turbulence for a flat piston. The results of the thesis enhance the understanding of the dynamic effects encountered during intake as well recognizing that a small tumble component has a strong effect on the flow structures prior to combustion. These results can be used to improve the simplified computational methods used to optimize the engine. / <p>QC 20150420</p>
539

DIETARY INTAKE IN RELATION TO METABOLIC SYNDROME AND ASSOCIATED RISKS IN CANADIAN ADULTS AND ADOLESCENTS

2014 October 1900 (has links)
Type 2 diabetes and cardiovascular disease (CVD), major public health concerns in Canada and worldwide, are the main outcomes of Metabolic Syndrome (MetS). MetS is a clustering of five chronic disease risk factors, including abdominal obesity, dyslipidemia (elevated triglycerides and reduced high-density lipoprotein cholesterol level), hypertension, and elevated fasting plasma glucose. Abdominal obesity and insulin resistance are the main factors contributing to development of MetS and thus CVD and diabetes. Further, dyslipidemia (specifically the total cholesterol/HDL-C ratio) is necessary to be monitored in people with these diseases or risk factors. The Canadian Health Measures Survey (CHMS) has direct health measurements that provide the opportunity to identify risk factors associated with chronic disease. Further, dietary intake has been assessed in CHMS, which can be utilized to evaluate the association with diseases and risk factors controlling for potential covariates. To examine the association between dietary intake with MetS and associated risks and diseases in Canadian adults and adolescents, data from CHMS cycle1, 2007-2009 (n=5604, aged 6-79 y) were used in which dietary intake was assessed using a semi-quantitative food frequency questionnaire. Frequency of food intake (times/day) and the distribution of individuals with and without disease or risk factors by socio-demographic characteristic was determined. Further, the association between dietary intake and each disease or risk factor was evaluated using logistic models. Data manipulation, cleaning, and creation of new variables were done using IBM SPSS statistics for windows, version 20. All statistical analyses were conducted by STATA/SE 11, StataCorp. As per Statistics Canada’s recommendation, data were weighted and bootstrapped using specific commands in STATA in order to be representative of the Canadian population. Physically active Canadians had significantly more milk and dairy product, fresh fruit and vegetable, and fruit and vegetable juice intake compared to inactive Canadians. Low-income households had significantly greater intakes of sugar-sweetened beverages (SSBs) and lower amounts of fresh fruit and vegetables than high-income households. Individuals with the lowest level of education had greatest potato and lowest fruit and vegetable juice intake. The prevalence of abdominal obesity (12-79 y), elevated TC/HDL-C ratio (20-79 y), MetS (12-79 y), and diabetes (20-79 y) was 35.7%, 20.5%, 18.3%, and 7.5%, respectively. The overall estimated percent risk of CVD over 10 years in adults aged 30-74 y was 8.66%. Abdominal obesity had the greatest contribution (~90%) to development of MetS in each age group compared to other components of MetS. Also, abdominal obesity was a strong significant predictor for development of other risk factors and chronic diseases including elevated TC/HDL-C ratio, diabetes, and CVD (OR: 6.12, CI: 2.68-13.96; OR: 2.25, CI: 1.24-4.06, OR: 1.4, CI: 1.06-1.87, respectively). High consumption of diet soft drink was associated with increased risk of abdominal obesity, Mets, diabetes, and elevated TC/HDL-C ratio. High consumption of fruit and vegetables and cereal was associated with decreased risk of CVD over 10 years whereas potato intake increased the risk. Intake of nuts appeared to be associated with reduction in the risk of MetS among Canadians. Dietary fat intake of one to less than 5 times/week was associated with increased risk of abdominal obesity in individuals over 40 years of age compared to 12-19 y individuals. Further, “ever drinking” alcohol compared to “never drinking” alcohol was associated with decreased risk of diabetes and elevated TC/HDL-C ratio. Low level of education contributed to development of abdominal obesity. Thus, abdominally obese individuals with specifically elevated TC/HDL-C ratio are at risk of developing MetS, CVD, and diabetes. They need to be educated with specific focus on physical activity, and greater intake of fruit and vegetables, nuts, and lower intake of dietary fat, diet soft drinks, and potato. Additionally, considering the social determinants which might contribute to increase the risk of chronic diseases or risk factors such as income, housing, accessibility to facilities in neighborhoods, school programs, or community programs is essential.
540

The relationship between calcium, vitamin D status, anthropometry, physical activity and bone density in Black men : a case control study / Merensia Groenewald

Groenewald, Merensia January 2003 (has links)
Osteoporosis literally means 'porous bone" and is characterized by an increase in bone fragility and susceptibility to fracture, which typically involves the wrist, spine and hip (South African Medical Association (SAMA) Working Group, 2000). In South Africa osteoporosis and fractures are more common in whites than in blacks. African-American men experience hip fractures at a rate of only half of that of Caucasian men. The bone mass in Africans were found to be 6 - 12 % higher than in Caucasians at all ages. A higher peak bone density at skeletal maturity in African-Americans were found, so that despite comparable age related bone loss, African Americans reach the fracture threshold less frequently than whites. Age-related bone loss that begins later, is less severe, or occurs in different skeletal sites in African-Americans than whites (Luckey et al., 1996). American whites have a higher bone turnover than American blacks, but in contrast to this American data. South African blacks may have a higher bone turnover and lower bone density than whites (Daniels et a/., 1995). If it is compared with Caucasians a lower rate of hip fracture in South African blacks were found, despite lower bone density at all ages (Villa, 1994). The lower fracture rate in blacks than in whites is because of greater bone mass and higher bone turnover leading to more frequent renewal of damaged bone. Blacks excrete less urinary calcium, and show no skeletal sensitivity towards the parathyroid hormone. Few studies focus on older black South African men and osteoporosis. Objectives The aim of this study was to investigate the relationship of calcium intake, vitamin D status, anthropometry and physical activity and bone density in black South African men. Methods A case-control study design was used, in which variables associated with bone density were compared. The case group were men with fractures of the proximal femur, the proximal humerus or the distal radius and an equal number of age-matched healthy black men (with not more than a 5-year age difference) with no fracture (the proximal femur and humerus and distal radius) previously, was recruited as a control group. Bone density was measured with DEXA. Fat percentage was measured with a Tanita scale. Biochemical analyses were done. Questionnaires were used to gather demographic, activity and dietary information. To our knowledge, this is the first case-control study on osteoporotic fractures in South African black men. Results Both the groups' bone mineral densities were lower than recommended. The bone density of the case group for lumbar and hip regions was 0.86 and 0.88 and the control group's bone density for lumbar region was 0.95 and hip region 0.91. The control group was more physically active and had a better nutritional status than the case group. The control group's calcium intake was higher but the vitamin D status was lower than the case group. Both calcium and vitamin D status were not statistically significant (pc0.5), between the two groups. Body mass indices of the groups were the same. The serum albumin was higher in the control group than in the case group. The case group serum calcium was higher than the control group. Both serum albumin and serum calcium were statistical significant between the two groups. There were no statistically significant differences in any of the other biochemical variables between the two groups. Serum phosphate and serum vitamin D were statistical significant for bone density of the hip and lumbar regions. Conclusion To conclude it seems logical to suggest a healthy diet with optimal macro- and micro nutrient intake. Maintain ideal body weight and body fat percentage and recommend regular but moderate-weight-bearing exercise from a young age throughout adult life, as part of a strategy to prevent and treat osteoporosis. In the present study black South African men present with low bone mineral density, but other studies indicated a lower rate of hip fracture in South African blacks, despite lower bone density at all ages. It can be recommended that other factors may play a role in black South African men with osteoporosis. Factors such as serum phosphorus, 25-hydroxy-vitamin D, body mass index (BMI), physical activity index (PAI), animal protein, total fat intake and dietary calcium are important determinants of BMD in older South African blacks, as shown in the present study. Osteoporosis is a multi factorial problem and must be treated that way. / Thesis (M.Sc. (Dietetics))--North-West University, Potchefstroom Campus, 2004.

Page generated in 0.3753 seconds