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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.
161

An exploratory study of change mechanisms for ambivalence reduction in young adult cyclical relationships

Washburn-Busk, Michelle January 1900 (has links)
Master of Science / School of Family Studies and Human Services / Amber V. Vennum / Cyclical relationships (where multiple break-ups and renewals have occurred) have been characterized as being in a state of “stable instability” (Vennum & Johnson, 2015), and emerging adulthood has been deemed a critical phase of relational development and learning, as well as a time marked by instability (Arnett 2000; 2007). While the research continues to expand on what we know about the concurrent and enduring risks for distress associated with relationship cycling, little is known about what change mechanisms/interventions may reduce these risks, or how helping professionals (therapists, relationship educators) can specifically assist young adults in cyclical relationships. After conducting five focus groups, researchers found specific factors that promote or detract from “decision-making resiliency”, or DMR. Specific points of intervention for professionals working with cyclical relationships to promote DMR are discussed, which included identity development, communication, power/control dynamics and intentionality. Building off of what is known about the nuances of cyclical relationships, this study aims to inform assessments and intervention(s) that would help bolster resilience and decision-making skills in cyclical couples (or couples who have slid into relationships and are, thus, at risk for cycling) in an effort to reduce further distress.
162

Analyzing Nitrogen in Silicate Glasses by Secondary Ion Mass Spectrometry

January 2016 (has links)
abstract: Volcanic devolatilization is one of the major processes in the global nitrogen cycle. Past studies have often estimated the magnitude of this flux using volcanic emission measurements, which are limited to currently active systems and sensitive to atmospheric contamination. A different methodological approach requires appropriate analytical parameters for nitrogen analysis in silicate glasses by secondary ion mass spectrometry (SIMS), which have not yet been established. To this end, we analyze various ion implanted basaltic and rhyolitic glasses by SIMS. We demonstrate that water content significantly affects the ion yields of 14N+ and 14N16O−, as well as the background intensity of 14N+ and 12C+. Application of implant-derived calibrations to natural samples provide the first reported concentrations of nitrogen in melt inclusions. These measurements are from samples from the Bishop Tuff in California, the Huckleberry Ridge Tuff of the Yellowstone Volcanic Center, and material from the Okaia and Oruanui eruptions in the Taupo Volcanic Center. In all studied material, we find maximum nitrogen contents of less than 45 ppm and that nitrogen concentration varies positively with CO2 concentration, which is interpreted to reflect partial degassing trend. Using the maximum measured nitrogen contents for each eruption, we find that the Bishop released >3.6 x 1013 g of nitrogen, the Huckleberry Ridge released >1.3 x 1014 g, the Okaia released >1.1 x 1011 g of nitrogen, the Oruanui released >4.7 x 1013 g of nitrogen. Simple calculations suggest that with concentrations such as these, rhyolitic eruptions may ephemerally increase the nitrogen flux to the atmosphere, but are insignificant compared to the 4 x 1021 g of nitrogen stored in the atmosphere. / Dissertation/Thesis / Masters Thesis Geological Sciences 2016
163

Association Between Mindful Eating and Weight Cycling in Middle Age Women

January 2016 (has links)
abstract: Introduction: Weight cycling is defined as happening when an individual intentionally loses weight and then subsequently regaining the weight over time. Weight cycling has been associated with a number of adverse health consequences and is a risk factor for cardiovascular disease. The large majority of behaviorally based weight loss interventions typically result in full weight regain often with additional weight gained over time with each repeated bout of weight cycling. Mindful eating, which is defined as a non-judgmental awareness of meal related factors, has been found to influence negative behaviors related to weight cycling. Purpose: The purpose of this study was to examine the association between mindful eating and weight cycling in middle aged women. Methods: This study used an observational design to explore the relationships and characterize responses to the Mindfulness Eating Questionnaire (MEQ) in 75 overweight women (BMI > 25) who self-reported a history of weight cycling using a weight cycling index (WCI). The participants were divided into three groups: non-cyclers (NC) less than three cycles of 10 lbs; moderate cyclers (MC) at least three weight cycles of 10lbs; and severe cyclers (SC) at least three weight cycles of at least 20lbs. Results: NC were significantly (p < 0.05) younger and had lower BMI than the MC and SC groups. There were no significant differences in any of the MEQ subscores based on WCI groups. There were no significant relationships between WCI and any of the MEQ subscores. Conclusion: The Mindful Eating Questionnaire (MEQ), was an insufficient discriminatory measure for use in an observational study on a complex behavior such as weight cycling. Further research to understand eating behavior domains, mindful awareness skills, and risk of weight cycling is needed. / Dissertation/Thesis / Masters Thesis Exercise and Wellness 2016
164

Efeito do exercício aeróbio prévio realizado em diferentes cadências de pedalada sobre o número máximo de repetições na musculação e a capacidade de saltos

Ruas, Vinícius Daniel de Araújo [UNESP] 15 June 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-15Bitstream added on 2014-06-13T20:49:25Z : No. of bitstreams: 1 ruas_vda_me_rcla.pdf: 912357 bytes, checksum: 39029679087dd76e4d8e693443be7ed4 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Em muitos programas de condicionamento físico ou de treinamento esportivo, os indivíduos têm de realizar exercícios aeróbios e de força na mesma sessão. No entanto, o treinamento concorrente demanda adaptações específicas para a melhora do rendimento aeróbio e do rendimento de força, e pode, dependendo das condições que forem realizados, comprometerem o rendimento da força. Portanto, os objetivos deste estudo foram: a) Analisar o efeito do exercício aeróbio realizado no ciclismo sobre a força muscular subseqüente, e; b) Verificar se o efeito do exercício aeróbio prévio é dependente do tipo de exercício de força realizado. Doze indivíduos do gênero masculino fisicamente ativos (23 l 3,7 anos, 77,2 l 8,9 kg, 179,3 l 4 cm, 14,34 l 2,99% gordura) executaram 2 testes incrementais até a exaustão em diferentes cadências de pedalada (50 rev.min-1 e 100 rev.min-1) para determinação do LAn, e um protocolo para a determinação da carga equivalente a 10 repetições máximas (10RM) em um aparelho leg-press 45°. Após a realização destes, os mesmos executaram três séries de repetições máximas com a carga de 10RM no leg-press (L) ou três séries de 10 saltos máximos em uma plataforma de saltos (S), nas seguintes condições: 1) Controle (LC e SC); 2) L50 e S50 após a realização de um exercício de 30 minutos no LAn na cadência de 50 rev.min-1; 3) L100 e S100 após a realização de um exercício de 30 minutos no LAn na cadência de 100 rev.min-1. Houve uma redução significante do número de repetições na primeira série nas condições L50 (10 l 1) e L100 (9 l 2) em relação à LC (12 l 2), e na terceira série na condição L100 (6 l 2) comparada à LC (9 l 1). Houve uma redução significante na altura média de saltos... / In several physical conditioning and sports training programs, individuals have to perform aerobic and strength exercises in the same training session. However, the concurrent training demands specific adaptations to the improvement of aerobic and strength performance and, depending of the conditions which they are performed, the strength performance can be compromised. Thus, the purposes of this study were: a) To analyze the effect of aerobic exercise performed in cycling on subsequent muscular strength, and; b) To analyze if the effect of previous aerobic exercise is dependent on the type of the strength exercise. Twelve active males (23 l 3.7 years, 77.17 l 8.86 kg, 179.33 l 4.03 cm, 14.34 l 2.99% body fat) performed 2 incremental tests until exhaustion in different pedal cadences (50 rev.min-1 and 100 rev.min-1) to in order to determine the anaerobic threshold (AT), and a protocol to determine the workload corresponding to 10 maximal repetitions (10RM) in leg press 45°. Then, they performed 3 sets of maximal repetitions with workload of 10RM in leg press (L) or 3 sets of 10 maximal countermovement jumps in a contact plate (S), in the following conditions: 1) Control (LC and SC); 2) L50 and S50 after 30 minutes of cycling at AT and pedal cadence of 50 rev.min-1; 3) L100 and S100 after 30 minutes of cycling at AT and pedal cadence of 100 rev.min-1. There was a significant reduction on the number of repetitions performed in the first set at the conditions L50 (10 l 1) and L100 (9 l 2) in relation to LC (12 l 2), and in the third set at the condition L100 (6 l 2) compared to LC (9 l 1). There was a significant reduction in the mean jump height in the first (29.0 l 4.1 cm) and third (29.1 l 2.9 cm) sets at S50 in relation to SC (32.0 l 3.3 cm and 31.8 l 2.9 cm, respectively). Thus, at these... (Complete abstract click electronic access below)
165

Efeito do exercício aeróbio prévio realizado em diferentes cadências de pedalada sobre o número máximo de repetições na musculação e a capacidade de saltos /

Ruas, Vinícius Daniel de Araújo. January 2007 (has links)
Orientador: Camila Coelho Greco / Banca: Emerson Franchini / Banca: Mauro Gonçalves / Resumo: Em muitos programas de condicionamento físico ou de treinamento esportivo, os indivíduos têm de realizar exercícios aeróbios e de força na mesma sessão. No entanto, o treinamento concorrente demanda adaptações específicas para a melhora do rendimento aeróbio e do rendimento de força, e pode, dependendo das condições que forem realizados, comprometerem o rendimento da força. Portanto, os objetivos deste estudo foram: a) Analisar o efeito do exercício aeróbio realizado no ciclismo sobre a força muscular subseqüente, e; b) Verificar se o efeito do exercício aeróbio prévio é dependente do tipo de exercício de força realizado. Doze indivíduos do gênero masculino fisicamente ativos (23 l 3,7 anos, 77,2 l 8,9 kg, 179,3 l 4 cm, 14,34 l 2,99% gordura) executaram 2 testes incrementais até a exaustão em diferentes cadências de pedalada (50 rev.min-1 e 100 rev.min-1) para determinação do LAn, e um protocolo para a determinação da carga equivalente a 10 repetições máximas (10RM) em um aparelho leg-press 45°. Após a realização destes, os mesmos executaram três séries de repetições máximas com a carga de 10RM no leg-press (L) ou três séries de 10 saltos máximos em uma plataforma de saltos (S), nas seguintes condições: 1) Controle (LC e SC); 2) L50 e S50 após a realização de um exercício de 30 minutos no LAn na cadência de 50 rev.min-1; 3) L100 e S100 após a realização de um exercício de 30 minutos no LAn na cadência de 100 rev.min-1. Houve uma redução significante do número de repetições na primeira série nas condições L50 (10 l 1) e L100 (9 l 2) em relação à LC (12 l 2), e na terceira série na condição L100 (6 l 2) comparada à LC (9 l 1). Houve uma redução significante na altura média de saltos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In several physical conditioning and sports training programs, individuals have to perform aerobic and strength exercises in the same training session. However, the concurrent training demands specific adaptations to the improvement of aerobic and strength performance and, depending of the conditions which they are performed, the strength performance can be compromised. Thus, the purposes of this study were: a) To analyze the effect of aerobic exercise performed in cycling on subsequent muscular strength, and; b) To analyze if the effect of previous aerobic exercise is dependent on the type of the strength exercise. Twelve active males (23 l 3.7 years, 77.17 l 8.86 kg, 179.33 l 4.03 cm, 14.34 l 2.99% body fat) performed 2 incremental tests until exhaustion in different pedal cadences (50 rev.min-1 and 100 rev.min-1) to in order to determine the anaerobic threshold (AT), and a protocol to determine the workload corresponding to 10 maximal repetitions (10RM) in leg press 45°. Then, they performed 3 sets of maximal repetitions with workload of 10RM in leg press (L) or 3 sets of 10 maximal countermovement jumps in a contact plate (S), in the following conditions: 1) Control (LC and SC); 2) L50 and S50 after 30 minutes of cycling at AT and pedal cadence of 50 rev.min-1; 3) L100 and S100 after 30 minutes of cycling at AT and pedal cadence of 100 rev.min-1. There was a significant reduction on the number of repetitions performed in the first set at the conditions L50 (10 l 1) and L100 (9 l 2) in relation to LC (12 l 2), and in the third set at the condition L100 (6 l 2) compared to LC (9 l 1). There was a significant reduction in the mean jump height in the first (29.0 l 4.1 cm) and third (29.1 l 2.9 cm) sets at S50 in relation to SC (32.0 l 3.3 cm and 31.8 l 2.9 cm, respectively). Thus, at these... (Complete abstract click electronic access below) / Mestre
166

Návrh dispozičního řešení cyklostezky v okolí obce Slavonice. / Layout proposal for the cycling trail in the vinicity of Slavonice town.

URBAN, Jiří January 2010 (has links)
The objektive of my thesis was to project the cycling trail in the vicinity of the town Slavonice.The cycling trail was projected around the village Maříž, which is the part of the town.The town Slavonice is located in Southern Bohemia, in region Jindřichův Hradec. At first, they were proposed two alternative. One of which was choise and her partial section was worked in the rang, which is submited for notification of constructions road, according to Decree 104/1997 Sb. Especially I went up from technical standards TP 179 - The Design of the cycle-way. I proposed a direction solution, vertical solution, constructional ordering and traffic signs. I situated in the proposed cycling trail picnick points, completed for notice board and bikes stand. In the framework of low possession relationships I wrote up lands, which can be touched of build-up the cycling trail. I have also done analyse existing cycling trails in surroundings. I refered in my thesis to diference between cycling trail and cyclo route too.
167

Plant adaptive strategies in relation to variable resource availability, soil microbial processes and ecosystem development

Aikio, S. (Sami) 05 June 2000 (has links)
Abstract Plants have evolved various adaptive strategies for balancing the benefits and costs of having a high affinity for resources, plasticity of growth allocation and mycorrhizal symbiosis. The relative growth rates of mycorrhizal and non-mycorrhizal plants were modelled for stable and variable nutrient availability. Mycorrhizal plants had higher growth rates at low and non-mycorrhizal plants at high nutrient availability. Variation in nutrient availability reduced the growth rate of mycorrhizal plants due to a high affinity for nutrients. However, mycorrhizal plants may be able to buffer against external fluctuations and therefore experience less environmental variation than non-mycorrhizal plants. Non-mycorrhizal plants may even benefit from variation. The optimal allocation of growth between shoot and roots depends on the availability of energy and nutrients. The optimisation model predicted that the requirement for phenotypic plasticity of shoot/root allocation is greatest in environments with low resource availability. Plants with a high affinity for resources required more plasticity in order to tolerate variation than plants with a low affinity. The model predicted a trade-off between the ability to deplete resources and the ability to tolerate resource fluctuations. Changes in the availability and ratio of resources lead to changes in the structure and composition of vegetation during primary succession. The field study of the forested phases of the land uplift island Hailuoto showed a successional change in the vegetation from the dominance of bryophytes and deciduous dwarf shrubs to dominance by lichens and evergreen dwarf shrubs. The humus layer became thinner and the availability of nutrients declined, while the C/N ratio of soil organic matter increased during succession indicating a decline in the quality of organic matter. The increased soil respiration rate indicates a successional increase in the energetic costs of decomposing organic matter. Nutrients mediate both direct and indirect trophic interactions. Indirect interactions of nutrient cycling are not explicit in continuous time models. A transformation to a discrete time model was shown to make the indirect interactions explicit as transition probabilities and allowed their dynamic contribution to be evaluated with an elasticity analysis. The importance of indirect interactions was greater in tundra than temperate forest and increased with the rate of nutrient cycling.
168

The effect of body mass change on cycling efficiency

Saunders, S. C. January 2016 (has links)
Cycling efficiency is a measure of the ability to convert stored energy into power, and is considered a key determinant of cycling performance. Cycling efficiency has recently been manipulated with various techniques, but most prominently with high intensity training in habitual cyclists and using calorie restriction in sedentary obese participants. It was therefore the primary aim of this thesis to explore the efficacy of utilising a short- and medium-term calorie restriction intervention, to manipulate efficiency with participants accustomed to cycling. A secondary aim was to investigate the validity of measuring efficiency in a field-based environment. Male club level cyclists were recruited for the investigations, which comprised of a moderate -500 kcal.day-1 deficit, utilising portion control and measuring efficiency at both absolute and relative steady-state intensities. Seventeen participants completed the short-term, two-week intervention which utilised a randomised cross-over design. Although a significant reduction in body mass was attained, RMR, gross and net efficiency across all intensities and TT power remained stable. Field and laboratory comparisons indicated that prior to statistical correction absolute efficiency was significantly lower in the field, but after accounting for differences in power, cadence and environmental conditions, no differences were present. Twenty-nine participants conducted the medium-term study and were assigned either to calorie restriction or to no dietary intervention. Following a reduction in mass in the calorie restriction group and an increase in the group given no dietary intervention, a significant interaction between mass and efficiency was found across gross and net efficiency workloads. A six week follow-up period indicated that the process of calorie restriction and not absolute body mass reduction was the main mechanism for altering efficiency. This thesis suggests that efficiency can be manipulated both positively and negatively with calorie manipulation, and that these changes are linked to both laboratory and field based performance.
169

Patterns in forest soil microbial community composition across a range of regional climates in Western Canada

Brockett, Beth 05 1900 (has links)
Soil microbial communities can be characterized by community structure and function (community composition) across a spectrum of spatial scales, and variation in soil microbial composition has been associated with a number of environmental gradients. This study investigates the structure and function of soil microbial communities under mature, undisturbed forested sites across a range of regional climates in British Columbia and Alberta, and also examines the variation in community composition within sites. Phospholipid fatty acid analysis was used to investigate the structure of soil microbial communities and total soil microbial biomass at each site. Extra-cellular enzyme assays established the functional potential of the soil microbial community at each site. Multivariate analysis of the data showed that the soil microbial communities under different forest types did significantly separate along the regional climate gradient by both community structure and function, despite high local variation in the communities. Soil moisture content and soil organic matter concentration consistently exhibited the strongest relationship with microbial community characteristics, although the functional and structural responses to the external drivers were different. Microbial community function and structure also changed with soil depth but not with time of sampling. Microbial community function was related to the regional annual average precipitation gradient. Most of the locations exhibited unique microbial community functional profiles in their soil layers; however the enzyme activities in the samples from the driest (Ponderosa Pine) and wettest (Mountain Hemlock) locations were notably different from each other and from those of the other locations, especially in the organic layers. The moist maritime-influenced Coastal Western Hemlock (CWH) forest exhibited microbial community structural characteristics which were unique from those of the other forest locations. The higher abundance of bacteria relative to fungi in the CWH forest soils may be related to the significantly higher available nitrogen concentrations at this site. / Forestry, Faculty of / Graduate
170

Does a decrease in seat height modify the effect of cadence on activation of the triceps surae during cycling?

Cawsey, Ryan Peter 11 1900 (has links)
Introduction: Several authors have demonstrated that, while cycling at a constant power output, EMG activity from the gastrocnemius increases systematically with increases in pedaling cadence, but that soleus EMG remains unchanged (Marsh & Martin 1995; Sanderson et al. 2006). The reason for this differential effect of cadence on the muscles of the triceps surae is unclear. Whatever factor(s) are responsible, it is assumed that, as they vary, the differential electromyographic response will vary accordingly. Decreasing the seat height has been shown to alter the kinematic characteristics of cycling (Too, 1990). The first objective of this study was to examine the effect of a decrease in seat height on the kinematics and muscle activation of the lower limb. The second objective was to investigate the effect of seat height on the relationship between cadence and triceps surae activation and, in doing so, to reveal possible factors mediating the response to changes in cadence. Methods: Participants pedaled a cycle ergometer at 200 Watts for five minutes at each of five cadences (50, 65, 80, 95, 110 rpm) and at each of two seat heights (100% and 90% trochanteric height). Kinematics of the lower limb were calculated from digitized video records of reflective markers placed on the skin over seven bony landmarks. EMG data were collected from eight lower-limb muscles. Results: The most notable findings were 1) that activation of the gastrocnemii was less in the low-seat condition and, contrary to what the findings of past research would suggest, was not associated with changes in muscle length; 2) that the medial and lateral gastrocnemii responded differently to changes in cadence at each seat height, suggesting that the functional roles of these muscles in cycling differ; 3) that several factors, including muscle length, muscle velocity, ankle angle and the direction of muscle action, were not responsible for the differential effect of cadence on activation of the soleus and gastrocnemius. Future research should investigate afferent feedback from proprioceptors in the knee joint and knee extensor muscles as possible factors mediating the effect. / Education, Faculty of / Kinesiology, School of / Graduate

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