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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.
41

Dispersal of Satyrid butterflies

Clarke, S. A. January 1988 (has links)
No description available.
42

Extending the theory of planned behaviour : a proposed integrated theoretical model using motivational and volitional variables, including interventions, to predict physical activity and physical activity change in a student population

Skår, Silje January 2011 (has links)
Physical activity is important to maintain a healthy lifestyle. Levels of physical activity decrease across the lifespan, and findings suggest only between 13-32% of University students are physically active at the recommended level. Research has found that ca. 50% of motivated individuals fail to enact on their intentions to be physically active. The theory of planned behaviour (TPB) was described, limitations and additions identified and its use outlined in three areas of investigation predicting physical activity: motivation, volition and intervention. Method: Student Activity and Lifestyle Study at Aberdeen (SALSA), a web-based survey, invited all students at the University of Aberdeen to respond to three questionnaires across the 2005/06 and 2006/07 academic years. SALSA received responses from 1418 and 1273 participants at the start of each academic year, respectively. Social cognitions (e.g. intention, perceived control), self-reported physical activity levels and attendance to the University’s sport facilities were measured. A double-blind randomised controlled trial investigated the efficacy two planning interventions, delivered via the internet, aiming to increase PA. Results and Summary: Findings suggest that students who are motivated benefit from making plans when, where and how to take part in physical activity, and plan how to cope with potential barriers and obstacles. Participants who are more certain of their intentions, aware of effort, the standards required and monitor themselves are more likely to be physically active, even though they are equally motivated and perceive themselves to be in control. Participant who were active in the past were more likely to attend the University’s sport facilities. However, the planning interventions did not increase students’ activity levels or attendance to the University’s sport facilities. Adherence to intervention protocol was low (between 58.8% to 76.7%) and participants dropping out of SALSA were large across both academic years.
43

Structural and functional studies on glucose-6phosphate dehydrogenase

Murray, Lynda A. January 1986 (has links)
1. The molecular weights of the G6PD subunits from the three yeast sources, bovine adrenals and rat liver were estimated by SDS-PAGE and found to be in the region of 55-59 K. An estimate of 46 K was similarly made for the G6PD subunit from the prokaryote, L. mesenteroides. 2. Two close bands or sometimes one diffuse band appeared on the polyacrylamide slab gel following electrophoresis and Coomassie blue staining for rat liver G6PD. These corresponded to the molecular weight region of about 57-59 K. So far, the evidence from peptide sequences does not reveal more than one subunit sequence. 3. G6PD from bakers' yeast was inactivated with sodium [1-. C] acetylsalicylic acid, following whichit was shown that 1.1 mole of 14 C moiety had been incorporated per enzyme subunit and that a lysine residue, essential to enzyme activity, had been modified. 4. Inactivation of bakers' yeast G6PD in the presence of high concentrations of substrate or coenzyme indicated that the acetylsalicylic acid was binding to the enzyme at a site which was directly or indirectly involved in substrate binding. The observation that high concentrations of coenzyme in the incubation mixture did not offer protection against acetylsalicylic acid inhibition was supplemented by TRNOE studies which showed no significant change in the conformation of coenzyme bound to bakers' yeast G6PD inactivated with acetylsalicylic acid compared with the active enzyme. 5. Acetylsalicylic acid did not inactivate rat liver G6PD to the same extent as the bakers' yeast enzyme. Inactivation of rat liver 14 G6PD with C-HIAB was relatively slow and resulted in the partial labelling of many cysteine residues. 6. Sequence studies on rat liver G6PD resulted in the isolation of a peptide which was homologous in sequence to the bakers' yeast G6PD tryptic peptide containing the reactive lysine residue, although no evidence for special reactivity of the corresponding lysine residue in the rat liver enzyme was found. 7. A high degree of sequence homology was noted between rat liver G6PD and human erythrocyte G6PD. It was also established that the human erythrocyte G6PD sequence published by Beutler (1983) was incorrect due to the misalignment of tryptic peptides.
44

Students' motivations and actions when they learn mathematics using CAS : a study using an activity theory approach.

Periasamy, Jeevasundarie 29 February 2012 (has links)
I explore students‟ motivations towards using Computer Algebra Systems (CAS) in learning mathematics, their associated actions and the relationship between their motivations and actions. Leontiev‟s (1978) philosophy of needs, motives and goals provides a powerful theory within which to understand students‟ motivations and actions in a learning context mediated by tools, thus the study is located within the framework of Leontiev‟s activity theory. It draws particularly on his notions of activity, actions and operations, as well as on Western motivational concepts of achievement goal theory and expectancy-value theory. Specifically, the notions of mastery approach goal-orientations, performance approach goal-orientations and social goal-orientations are examined, as are task value components (comprising „importance‟ of task, intrinsic reasons and extrinsic utility value). I also discuss indexes of motivation, which comprise choice of tasks, effort and persistence. An important theoretical contribution of this thesis lies in the elaboration of the aforementioned Western motivational constructs to the activity theoretical construct of motives. The latter conception comprises three groupings: self-related, cognitive and social motives, as postulated by the activity theorist Lompscher (1999). Set within the qualitative research paradigm, this study utilises case study methodology. Methods of data collection include four interviews for each of the three participants, observations of the participants during two problem-solving sessions, and consequent computer screen analyses of these sessions. The mathematical problems involved the numerical solutions of differential equations using MATLAB. The participants were students studying towards vocational (diploma) qualifications in Mechanical and Electrical Engineering at a comprehensive university in South Africa. My research illustrates the relationship between the expressed needs, motives and goals of the individuals regarding their involvement in the activity of using MATLAB in mathematical learning within a third semester, Mathematics 3 service course.
45

Identifying Dysregulated Protein Activities Using Activity-Based Proteomics

Martell, Julianne January 2016 (has links)
Thesis advisor: Eranthie Weerapana / Activity-based protein profiling (ABPP) is a chemical proteomic technique that allows for selective labeling, visualization, and enrichment of the subset of active enzymes in a complex proteome. Given the dominant role of posttranslational modifications in regulating protein function in vivo, ABPP provides a direct readout of activity that is not attained through traditional proteomic methods. The first application of chemical proteomics in C. elegans was used to identify dysregulated serine hydrolase and cysteine-mediated protein activities in the long-lived daf-2 mutant, revealing LBP-3, K02D7.1, and C23H4.2 as novel regulators of lifespan and dauer formation. The tools of ABPP were also utilized in studying protein interactions at the host-pathogen interface of V. cholerae infection, discovering four pathogen-secreted proteases that alter the biochemical composition of the host, decrease the activity of host serine hydrolases, and inhibit bacterial binding by a host-secreted lectin. Lastly, ABPP was used to study the targets of protein arginine deiminases (PADs) using a citrulline-specific activity-based probe (ABP), highlighting its utility in detecting biologically relevant PAD substrates as well as identifying mRNA processing factors as previously unknown targets of PAD. Taken together, these studies demonstrate the ability of ABPP to discover novel protein regulators of physiological and pathological processes. / Thesis (PhD) — Boston College, 2016. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.
46

Political identity of overseas Chinese: a study of the Indonesian Chinese in Hong Kong.

January 1984 (has links)
by Yung Wing Kwong. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1984 / Bibliography: leaves 144-157
47

Electrodermal activity & metamemory reports as predictors of memory retrieval

Flesch, Marie H. 15 November 2004 (has links)
Electrodermal activity (EDA), an indicator of arousal of the sympathetic nervous system, was investigated as a potential correlate of feeling-of-knowing (FOK) and tip-of-the-tongue (TOT) states. In Experiment 1, skin conductance was measured while participants answered general knowledge questions and made binary FOK and TOT judgments. Significant correlations were found between frequency of skin conductance responses (SCRs) and presence of both FOK and TOT states. In Experiment 2, warmth ratings were used and a follow-up clue session was added to offer participants the opportunity to resolve initially unanswered questions. SCR frequency during TOT states was significantly predictive of resolution during the clue period, although not as predictive as participants' warmth ratings. The potential of EDA as an on-line, non-intrusive measure of metamemory and memory retrieval is discussed.
48

Comparative Study of Bactericidal Activities of Six Different Disinfectants

KATO, NOBUO, TAKESHIMA, NOBORU, SUZUKI, ASAKATSU, NAMBA, YOSHIMICHI 03 1900 (has links)
No description available.
49

A longitudinal analysis of physical activity and overweight/obesity in adolescents in Saskatoon

Lai, Hang Thi Kim 23 April 2008
Overweight and obesity, one of the most common public health problems in affluent societies, have become epidemic not only in Canada but also throughout the world. Obesity is also a major contributor to the global burden of chronic disease and disability such as diabetes, hypertension, and cardiovascular disorders. <p>Studies have demonstrated clearly that higher intake of cholesterol and saturated fats and generally higher intake of energy-dense food are a key determinant of increasing levels of obesity and overweight in children. Physical activity is also recognized as a major factor in preventing obesity among children. Environmental factorsby which we mean both social (such as social support, social networks) and physical environment (such as access to physical activity amenities, roads and trails, grocery stores)in generally believed to have a powerful influence on either limiting or enhancing the effects of fundamental determinants (diet and physical activity) of obesity in children. This thesis focuses on one of the key determinants, physical activity, and in turn examines factors that are related to changing physical activity in children. <p>This research was designed to examine two major questions: (1) How do physical activity and overweigh/obesity change over time in a cohort of adolescents in Saskatoon? Are there differences in the patterns of change in overweight/obesity and physical activity between boys and girls? (2) What are the effects of family/friends and physical environments on the changing patterns of physical activity in this sample? <p>The data used in this study was taken from the in motion studies longitudinal data. Study participants include 837 adolescents from12-18 years of age from two high schools and five elementary schools from two diverse geographic areas in Saskatoon (low and high socioeconomic status). Physical activity patterns of adolescents were investigated over a five-month period (e.g., type, frequency, and duration). Participants were also asked to respond to questions on demographics, social support, perceived benefits and barriers of physical activity, and health practices. <p>The results of this study indicated that overweight/obesity increased with age, while physical activity decreased with age for both boys and girls. Boys overall were more likely to be physically active than were girls. Adolescents who received greater direct support from family members were 21% more likely to sustain their physical activity levels (relative odds 1.21; 95% CI 1.17, 1.24); in contrast, the more the familys indirect support the 5.4% less sustaining were the adolescents physical activity (relative odds 0.94; 95% CI 0.91, 0.98). Home environments which were rich in resources relevant to physical activity had 4% greater influence on adolescents physical activity levels, and this relationship was stronger than that of the influence of living in certain neighbourhoods (relative odds 1.04; 95% CI 1.03, 1.05). <p>This research shed some greater understanding of the impact of familys support and physical environment factors on adolescents continued physical activity levels. The implications of results for further research, targeted programs, and social policy is discussed in the thesis.
50

The Need for a Physical Education: Examining Physical Activity During The Transition to University

Kwan, Matthew 31 August 2011 (has links)
While physical activity (PA) declines across the lifespan, this does not occur linearly. Declines are most pronounced during the transition into early adulthood. This dissertation consisted of three studies examining PA decline during the transition into early adulthood: (1) to understand patterns of PA and other health behaviours of Canadians; (2) to understand reasons for PA declines during entry into university; and (3) to examine the feasibility and effects of a website-delivered PA intervention. Study 1 utilized multilevel modeling to identify patterns of PA, binge drinking and smoking among a nationally-representative cohort of adolescents (N = 640). Results found PA decline evident among all young adults transitioning into early adulthood regardless of educational trajectory – declines being most pronounced among college/university males – highlighting the saliency of PA decline, as other health behaviours stabilized or declined during early adulthood. Given justification for intervening with the university population, study 2 explored students’ perceptions of PA, and their preferences towards a PA intervention. Eight focus groups were conducted with first-year university students (N = 45). Results found students being concerned with PA decline, and were receptive to an Internet-based intervention. However, such concerns are inflected with ambivalence, potentially posing a challenge for interventionists. Findings from studies 1 and 2 informed the development of a website-delivered PA intervention – ‘Active Transition’. Pre-testing was conducted with first-year students (N = 15) and PA experts (N = 7), which found the website and its content being acceptable and usable. Results of the efficacy trial (N = 65) found Active Transition to successfully attenuate declines in PA cognitions, and to some extent, PA behaviours. This confirms the Internet being a useful tool for delivering PA interventions in this population. However, given modest compliance in terms of usage, future work is required to evaluate the addition of more current/popular strategies for engaging students. Overall, this dissertation has provided justification for why it is critical that research continues work with this population, and has provided the foundations in helping with the long-term vision of implementing a population-level initiative to help students attenuate the significant declines in their PA behaviours.

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