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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.
191

Religion, Spirituality, HIV Symptoms and Health Related Quality of Life in HIV Infected African American Women Recovering from Substance Abuse

Jané, Dulce Maria 16 December 2010 (has links)
The aim of this study was to evaluate the potential contribution of religious involvement, spiritual well-being, existential well-being and HIV-related symptoms to health-related quality of life in HIV-infected African American women recovering from substance abuse. The study also examined whether religious and spiritual variables served as potential moderators between HIV symptoms and health-related quality of life. This study relied on data obtained as part of a larger longitudinal investigation of the effectiveness of Structural Ecosystems Therapy (SET) for HIV infected women in substance abuse recovery. A total of 175 participants were recruited from regional residential and outpatient clinics. The sample in this study included 99 African American women who had completed the required baseline assessment. It was hypothesized that religious involvement, spiritual well-being and existential well-being would be positively associated to various health-related quality of life indicators (i.e., physical functioning, social functioning, mental health functioning and health distress). On the other hand, HIV symptoms were hypothesized to be inversely related to the health-related quality of life indicators. Religious involvement, spiritual well-being and existential well-being were posited to moderate the relationship between HIV symptoms and the health-related quality of life indicators. Findings from the multivariate analysis of variance showed existential well-being to be significantly related to mental health functioning and health distress and HIV symptoms to be significantly related to mental health functioning and physical functioning. Results from the regression analyses also showed that after controlling for age, both existential well-being and HIV symptoms were significantly related to mental health functioning. Results suggest that increased symptom frequency is significantly associated with worse mental health while higher levels of existential well-being are significantly related to better mental health. No evidence was found in support of the hypothesized moderating role of religious involvement, spiritual well-being and existential well-being between HIV symptoms and health-related quality of life indicators. Research and clinical implications of these findings are discussed.
192

The Effects of Weaning Strategy on the Physiology and Performance of Beef Calves

Campistol, Cristina 01 December 2010 (has links)
Two experiments examined growth performance and physiological measures of stress in pre- and postweaned Angus steers (313 ± 24.5 kg; n = 48/Exp.), where steers were fitted with (YD) or without (ND) an anti-suckling device (Exp. 1), or provided (YS) or not provided (NS) a grain supplement (Exp. 2) for 7 d and weaned by fenceline (FS) or total separation (TS). Steers in Exp. 1 were weighed and bled on d 0, 3, 7 10, 14, 21, and 42, and in Exp. 2, on d 0, 7, 10, 14, and 21 and provided a grain supplement on d 7-21. In Exp. 1, weight gain was not different (P = 0.74) between ND and YD steers during preweaning. The YD-FS steers lost weight (P = 0.01) by d 10 compared with YD-TS steers. Hematocrit (Hct) increased (P = 0.04) in YD but not ND steers on d 3. Neutrophil:lymphocyte ratio (N:L) increased (P < 0.01) in all steers by d 7. Cortisol values in YD-FS steers were higher (P < 0.05) compared with YD-TS steers on d 10 and 21. The ND-FS steers had higher (P = 0.04) interferon-gamma (IFN) concentrations on d 10 compared with all YD steers. Haptoglobin (HAP) values increased (P < 0.01) in all steers by d 3. The FS steers had higher (P < 0.01) ceruloplasmin (CER) values by d 10 than TS steers regardless of preweaning treatment. Ovalbumin-specific IgG increased (P < 0.01) in all steers 10 d following its administration. In Exp. 2, NS-TS steers lost weight (P < 0.01) between d 7 and 10 compared with the remaining steers. The YS steers had higher cortisol, N:L and CER on d 7 compared with NS steers. Moreover, NS steers had higher (P < 0.01) Hct on d 10 than YS steers. Based upon physiological and growth performance data, it may be concluded that use of an anti-suckling device prior to weaning does not improve the animals’ well-being and, providing a grain supplement beginning 7 d prior to weaning may temper the animals’ stress response due to weaning when total separation is employed.
193

Saliency of one's heritage culture Asian cultural values and its interconnections with collective self-esteem and acculturation/enculturation as predictor of psychological well-being of people of Chinese descent /

Lee, Szu-Hui, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 72-84).
194

Expressive writing, relationships, and health

Eells, Jennifer Emilia, January 2006 (has links)
Thesis (Ph.D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 27, 2007) Vita. Includes bibliographical references.
195

A model for matrix acidizing of long horizontal well in carbonate reservoirs

Mishra, Varun 02 June 2009 (has links)
Horizontal wells are drilled to achieve improved reservoir coverage, high production rates, and to overcome water coning problems, etc. Many of these wells often produce at rates much below the expected production rates. Low productivity of horizontal wells is attributed to various factors such as drilling induced formation damage, high completion skins, and variable formation properties along the length of the wellbore as in the case of heterogeneous carbonate reservoirs. Matrix acidizing is used to overcome the formation damage by injecting the acid into the carbonate rock to improve well performance. Designing the matrix acidizing treatments for horizontal wells is a challenging task because of the complex process. The estimation of acid distribution along wellbore is required to analyze that the zones needing stimulation are receiving enough acid. It is even more important in cases where the reservoir properties are varying along the length of the wellbore. A model is developed in this study to simulate the placement of injected acid in a long horizontal well and to predict the subsequent effect of the acid in creating wormholes, overcoming damage effects, and stimulating productivity. The model tracks the interface between the acid and the completion fluid in the wellbore, models transient flow in the reservoir during acid injection, considers frictional effects in the tubulars, and predicts the depth of penetration of acid as a function of the acid volume and injection rate at all locations along the completion. A computer program is developed implementing the developed model. The program is used to simulate hypothetical examples of acid placement in a long horizontal section. A real field example of using the model to history match actual treatment data from a North Sea chalk well is demonstrated. The model will help to optimize acid stimulation in horizontal wells.
196

The influence of the lighting environment on performance and well-being in offices

Kronqvist, Annika January 2010 (has links)
This paper presents an experimental study with 47 participants on the influence of lighting on performance and well-being in an office environment. Well-being, alertness and performance were evaluated and measured in two rooms with artificial lighting and one room with day lighting. The evaluations were correlated to cortisol/melatonin saliva samples, illuminance and spectral compo-sition of the lighting. The results show day lighting to have a sustained influence on alertness and performance and it is furthermore concluded that the level of cortisol in saliva was not influenced by the illuminance and did not have an influence on performance. The participants preferred a lighting with different kinds of light sources to a more neutral lightning and gave it higher ratings for well-being.The analysis shows that comfort did not influence alertness.
197

The Contribution of Domain Satisfaction to Life Satisfaction: Convergent Validity of Importance Measures

Zou, Christopher 31 December 2010 (has links)
Global life satisfaction is the evaluation of one’s life among important domains. Therefore, importance ratings should improve the relation between domain satisfaction and life satisfaction. However, this is not the case because studies have shown that importance ratings do not improve the model. This study examined the validity of importance and satisfaction measures using a multi-method approach. 316 participants were recruited in friendship pairs to fill out a series of questionnaires about themselves and their friend. Based on the self-informant agreement scores, there is some validity in importance and the satisfaction ratings. The importance measures for some domains also predicted people’s behavioural patterns. Indirect importance ratings were also extracted using regression and correlational analysis. In conclusion, there was also evidence for convergent validity of the direct and indirect importance measures. Therefore, people do think about the important domains to some extent when making a global life satisfaction judgment.
198

The Contribution of Domain Satisfaction to Life Satisfaction: Convergent Validity of Importance Measures

Zou, Christopher 31 December 2010 (has links)
Global life satisfaction is the evaluation of one’s life among important domains. Therefore, importance ratings should improve the relation between domain satisfaction and life satisfaction. However, this is not the case because studies have shown that importance ratings do not improve the model. This study examined the validity of importance and satisfaction measures using a multi-method approach. 316 participants were recruited in friendship pairs to fill out a series of questionnaires about themselves and their friend. Based on the self-informant agreement scores, there is some validity in importance and the satisfaction ratings. The importance measures for some domains also predicted people’s behavioural patterns. Indirect importance ratings were also extracted using regression and correlational analysis. In conclusion, there was also evidence for convergent validity of the direct and indirect importance measures. Therefore, people do think about the important domains to some extent when making a global life satisfaction judgment.
199

Health-enhancing physical activity and eudaimonic well-being

Besenski, Leah Joanne 16 September 2009
Numerous studies have investigated the relationship between physical activity and physiological health (e.g., Burke et al., 2006; Irwin, 2004). Less attention has been paid to the contribution of physical activity on psychological well-being (Fox et al., 2000), and more specifically eudaimonic well-being, which reflects optimal psychological functioning and development at ones maximum potential (Ryff, 1989, 1995). This study investigated the role that health-enhancing physical activity (HEPA; any form of physical activity that benefits health and functional capacity; Miilunpalo et al., 2000) plays in eudaimonic well-being, which Ryff conceptualizes in terms of six dimensions: (1) Autonomy (i.e., being self-determined and independent); (2) Environmental Mastery (i.e., having a sense of mastery and competence in managing the environment); (3) Personal Growth (i.e., having a feeling of continued development); (4) Positive Relations with Others (i.e., having warm, satisfying, and trusting relationships with others); (5) Purpose in Life (i.e., having goals and a sense of direction in life); and, (6) Self-acceptance (i.e., possessing a positive attitude toward the self).<p> Employing Ryffs (1989, 1995) perspective of eudaimonic well-being, this study explored whether or not experiencing eudaimonia during HEPA moderates the relationship between HEPA and eudaimonic well-being. Additionally, it explored whether or not the relationship between experiencing eudaimonia during HEPA and eudaimonic well-being is mediated by basic need satisfaction. Undergraduate university students (N = 524; Mage = 20.7 years) completed an online survey including the Scales of Psychological Well-Being (Ryff & Keyes, 1995), the Short Questionnaire to Assess Health-enhancing Physical Activity (Wendel-Vos et al., 2003), the Hedonic and Eudaimonic Motives for Activity scale (Huta & Ryan, 2008), and the Psychological Need Satisfaction in Exercise Scale (Wilson, Rogers, et al., 2006). While level of HEPA was not significantly related to eudaimonic well-being (r = .05, p = .24), experiencing hedonia during HEPA (i.e., enjoying oneself, experiencing pleasure; r = .40, p < .01), experiencing eudaimonia during HEPA (r = .37, p < .01), and basic need satisfaction (r = .46, p < .01) were significantly related to eudaimonic well-being. Although experiencing eudaimonia during HEPA did not moderate the relationship between HEPA and eudaimonic well-being, experiencing eudaimonia during HEPA accounted for a significant 2.2% unique variance in eudaimonic well-being beyond HEPA and experiencing hedonia during HEPA (the full model accounted for a significant 18.2% of the variance in eudaimonic well-being).<p> Furthermore, the data were consistent with a model of partial mediation in that basic need satisfaction partially accounted for the relationship between experiencing eudaimonia during HEPA and eudaimonic well-being, supporting the proposition put forth by Ryan et al. (2008) that positive psychological well-being is a result of eudaimonic living that facilitates the satisfaction of our basic psychological needs. Findings from this study suggest that what appears to be significant in the relationship between HEPA and eudaimonic well-being is not the level of activity, but rather what is experienced during the activity. Future research may explore the directionality of the relationship by examining the extent to which eudaimonic well-being influences what is experienced during activity.
200

Multiscale Reservoir Simulation: Layer Design, Full Field Pseudoization and Near Well Modeling

Du, Song 14 March 2013 (has links)
In the past decades, considerable effort has been put into developing high resolution geological models for oil and gas reservoirs. Although the growth of computational power is rapid, the static model size still exceeds the model size for routine reservoir simulation. We develop and apply a variety of grid coarsening and refinement algorithms and single and multiphase upscaling approaches, applied to tight gas and conventional reservoir models. The proposed research is organized into three areas. First the upgridding of detailed three dimensional geologic models is studied. We propose an improved layer design algorithm with considerations of accuracy and efficiency. This involves developing measures of reservoir heterogeneity and using these measures to design an optimal grouping of geologic model layers for flow simulation. The optimal design is shown to be a tradeoff between the desire to preserve the reservoir heterogeneity and a desire to minimize the simulation time. The statistical analysis is validated by comparison with flow simulation results. Accurate upgridding/upscaling of single-phase parameters is necessary. However, it does not always satisfy the accuracy requirements, especially for the model which is aggressively coarsened. We introduce a pseudoization method with total mobility and effective fractional flow as the major targets. This pseudoization method helps to push upgridding/coarsening degree to the limit but still be able to reproduce the fine scale field performance. In practice, it is common to not use a different set of pseudos for every coarse cell; only a limited number of pseudo functions should be generated for different “rock types” or geological zones. For similar well patterns and well control conditions, applying pseudo is able to reproduce the fine scale performance for different simulation runs. This is the second proposed research area. Finally, it is necessary to increase flow resolution for precise field history matching and forecasting. This has received increasing attention, especially when studying hydraulically fractured wells in unconventional reservoirs. We propose a multiscale reservoir simulation model combining local grid refinement (LGR) and pillar-based upscaling for tight gas reservoir performance prediction. Pillar-based coarsening away from the wells is designed for tight gas reservoirs. It compensates for the extra computational cost from LGR, which is used to represent hydraulic fractures. Overall reservoir performances, including the accuracy and efficiency, are evaluated.

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