Thesis (M.S.)--Indiana University, 2007. / Includes bibliographical references.

Thesis (M.S.)--Indiana University, 2007. / Includes bibliographical references (leaves 38-40).

Thesis (M.S.)--Indiana University, 2005. / Includes bibliographical references. Also available online (PDF file) by a subscription to the set or by purchasing the individual file.

Thesis (M.S.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains x, 154 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.

Adolescence is a crucial period for bone development and exercise can enhance bone acquisition during this period of life. However, there is a lack of scientific evidence on how different loading sports practiced during adolescence can affect bone development in males. The present thesis is part of the PRO-BONE study and aimed to investigate the cross-sectional and longitudinal effects of participation in football (osteogenic sport), swimming and cycling (non-osteogenic sports) on bone mass, bone geometry, texture and bone metabolism in adolescent males. An active control group has been included too. Additionally, the thesis examined the effect of a 9-month jumping intervention programme on bone outcomes in adolescent males involved these sports. Cross-sectional findings from Chapter 4 show that footballers have better bone status than swimmers, cyclists and controls (7 to 21 %), and that there are no differences between participants of non-osteogenic sports and controls. Chapter 5 identifies that lean mass is the strongest determinant of bone outcomes, followed by football participation and height in adolescent male athletes, whereas the contribution of the other predictors, such as nutrition, physical activity and fitness, is site specific. Longitudinal evidence in Chapters 6 and 7 show that bone mass (5 to 8 %) and geometry (4 to 10 %) is higher in adolescent male footballers compared to swimmers and cyclists after one year of sport specific training, and that there are no differences in bone development between non-osteogenic sports groups and controls. Chapters 8 and 9 indicate that a 9-month jumping intervention programme can improve bone outcomes only in male adolescents participating in swimming and cycling (4 to 13 %), but not in those engaged in football, while it can improve fitness outcomes in all 4 groups (4 to 8 %). Collectively, the present thesis contributes to the literature by providing novel evidence in adolescent male athletes on the effects of popular sports such as football, swimming and cycling on bone status and development, and that a jumping intervention programme can improve bone development in those involved in non-osteogenic sports.

The biology and ecology of an indigenous, non-pest insect on an indigenous host plant were investigated. The study includes a taxonomic description of this new species, an account of its general biology, monitoring of the seasonal fluctuations in numbers of the psyllid and its hymenopterous parasitoids, and a study of various aspects of the host plant, including nitrogen levels, water stress, leaf hardness, and the effect of cutting, in relation to spatial and temporal differences in insect population numbers. Natural enemies, inter- and intra-specific competition had very little determining influence on the population numbers of the psyllid. Temperature and humidity had little direct effect, but may have influenced the population dynamics via its effects on the host plant. Seasonal patterns in psyllid numbers followed fluctuations in nitrogen levels; statistically valid correlations were obtained between leaf nitrogen and psyllid numbers on individual trees at various times. These findings were supported by the results of preliminary laboratory experiments employing different fertilizer treatments. No effect of water stress or leaf hardness was clearly discerned. Cutting of trees altered the characteristics of the subsequent regenerative growth so as to allow massive psyllid infestations to develop, thus showing the tremendous importance of the host plant in determining population levels in this insect. Preliminary investigations of the nature and mechanism of this effect were conducted, and its significance is discussed. The relevance of these findings to modern concepts of regulation in insect populations and to principles of pest management is discussed.

Current theories in psychology now suggest that behaviours that were primarily associated with psychotic disorders, such as delusional experiences, can be observed in the healthy general population (van Os, Linscott, Myin-Germeys, Delespaul and Krabbendam, 2009). Delusions, a common symptom of schizophrenia, have been associated with a tendency to jump to conclusions. In simpler terms, it has been discussed that those that experience delusions will reach final decisions earlier than controls upon the basis of little evidence (Huq, Garety and Hemsley, 1988). The aim of the research was to investigate the factors that may moderate this susceptibility to jump to conclusions amongst the sub-clinical range of delusional thinking amongst the distinct construct measures of the Peters et al. Delusions Inventory (PDI: Peters, Day and Garety, 1996). Numerous studies were conducted to investigate: intelligence, probability calculation ability, experimental task design and task delivery upon the emergence of the jump to conclusions bias (Chapters II-VI). Moderator analyses identified that task design and task delivery were strong predictors of the quantity of information requested prior to finalising a decision; with restricted data gathering occurring with the use of face-to-face abstract tasks (Chapter III and VI B). When tasks included neutral and emotionally-unstimulating material, a data gathering bias was either not observed (Chapter II) or data gathering was enhanced amongst those with high belief conviction. Perceived life stress, perceived task stress and specific reasoning styles were investigated in an attempt to explain the situation-specific differences (Chapters VII and VIII). It was concluded in the General Discussion that delusional thinking appears to be associated with hasty decision making, under specific situational circumstances and can differ between the distinct constructs of the PDI measure (Peters et al. 1996). Sub-clinical delusional ideation is an overall summation of belief distress, preoccupation and conviction. The current research argues that the three psychological dimensions of delusional belief can influence decision making uniquely; specifically in relation to the emergence of a data gathering bias.

This thesis explores the decision making styles demonstrated by people with anorexia. It is presented as three papers: 1) a literature review; 2) an empirical study and 3) a personal reflection on the processes involved in conducting the research and critical appraisal of the issues which emerged. The literature review in Paper 1 systematically explored the existing research that examined decision making in disordered eating populations. Twenty seven papers were reviewed and their findings synthesised to develop a comprehensive overview of decision making across a spectrum of disordered eating populations. Parallels in decision making across diagnostic categories were identified, and the relationship between decision making and clinical, personality and demographic variables was also explored. Methodological quality of studies was reviewed; recommendations for future research were also identified. Broadly, the findings indicated that similar styles of decision making appear evident in anorexia and bulimia. No characteristically different decision making patterns were demonstrated by people with eating disorder-not otherwise specified or by people recovered from anorexia. The evidence regarding nature of decision making in obesity and binge eating disorder was less conclusive. The empirical study conducted in Paper 2 endeavoured to enhance our understanding of the nature of decision making in disordered eating. The study examined a specific decision making bias i.e. the ‘jumping to conclusions’ bias in people with anorexia. The study also explored whether eating disorder related beliefs in anorexia could be considered to be of ‘delusional’ proportions. The results indicated that compared with a healthy control group, people with anorexia did not display a ‘jumping to conclusions’ bias. They did not display a tendency to make decisions on the basis of little evidence. The majority of individuals with anorexia did demonstrate limited insight into their eating disorder related beliefs, though only a minority subgroup held beliefs that could be considered ‘delusional’. Methodological limitations and clinical implications of the findings are discussed. The third paper provides a personal and critical reflective account of the processes involved in conducting both the literature review and the scientific study. It critically appraises aspects of the research process including strengths and limitations of both studies. Implications for clinical practice, replication and directions for future research are also identified. This paper also includes personal reflections on the approaches used and the challenges encountered within these.

One of the most striking things about many animals is that they can be defined by the ways in which they move. Moving costs metabolic energy and is a significant contributor to the daily energy balance of organisms and therefore fitness. Balancing energy needs is critically important to species inhabiting areas of limited resources. The metabolic cost of locomotion is influenced by physiological, morphological and behavioural factors that vary across species. The influence of these factors within species is less well understood. The objective of my PhD is to elucidate the potential for variation in locomotor performance, in particular the energy consumed and the biomechanics of locomotion within a species, in response to differences in season, sex, age and the nature of the terrain. The Svalbard ptarmigan (Lagopus muta hyperborea) is the only year-round avian resident of the Arctic archipelago of Svalbard. Svalbard is characterized by extreme photoperiodic and climatic conditions, with 24 hours of daylight in summer and continuous darkness in winter, when ice makes food unpredictable. As a result, ptarmigan annually gain significant fat stores, as much as doubling their body mass in winter. The consequences of such large gains in mass upon the metabolic cost and biomechanics of terrestrial locomotion are yet to be quantified. The Svalbard ptarmigan represents a unique opportunity to gain insight into avian adaptations.Using respirometry, I present evidence that winter birds are able to carry their fat stores at no metabolic cost. Using kinematic and force plate data, I show that acquiring fat results in reduced locomotor performance in terms of speed and take-off ability. As well as exhibiting phenotypic variation, male and female Svalbard ptarmigan are behaviourally very different. I present evidence that these behavioural differences are reflected in the metabolic cost of locomotion. In particular, males are both more efficient and faster than female birds during both summer and winter. I suggest that this results from sexual selection upon male locomotor performance. Furthermore, I present data demonstrating that sub-adult males experiencing their first winter possess the same metabolic and speed capabilities of adults. These data may indicate that selection for improved male locomotor performance may act upon sub-adult birds. Regardless of season, age or sex, Svalbard ptarmigan must locomote on a predominantly sloping terrain. The influence of inclines upon the metabolic cost of locomotion in birds is poorly understood. I provide evidence that at the same degree of incline, the cost of lifting 1 kg by 1 vertical metre is similar regardless of season and is therefore dictated by increased positive work. However, this cost varies according to the degree of incline and may be influenced by gait.The principal findings of the 5 first author papers presented are that behavioural, physiological and morphological variation within a species can have significant impacts upon the metabolic cost of locomotion and other aspects of locomotor performance. The potential for intraspecific differences should therefore be taken into account in future research regarding the patterns of energy expenditure in animals.

Master of Science