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To be a fat woman is to experience a prolonged, personal battle with the body. The battle is enacted in a social context which is the site of remarkable consensus about the personal culpability of fat people for their bodily largeness; for women in particular the sanctions are especially powerful. In this research nine large women have engaged in a prolonged dialogue about the experience of being 'obese'. In the course of a feminist research endeavour, with a researcher who is similarly positioned, they have both contributed to and gained from a project which illuminates the experience of largeness alongside a critical examination of the discourses which shape body size.This dissertation critiques a dominant medical discourse which ignores conflicting research and supports a narrow view of health by simplistically linking increased body weight with poor health outcomes. Such is the hegemonic power of medicine that an examination of both nursing and popular literature in the area of study, reveals wide-spread acceptance of the notion that to be thin is to be healthy and virtuous, and to be fat is to be unhealthy and morally deficient. For nursing, the unquestioning obedience to medical teaching, raises serious questions about nursing's autonomy and separateness from medicine. Nurses have perpetuated an unhelpful and reductionist approach to their care of large women, in direct contradiction to nursing's supposed allegiance to a holistic approach to health care. Current strictures on women's body size and continued support for reduction dieting leave large women with the choice between two binary opposites; to diet or not to diet. Either choice has consequences which are traumatic and not health promoting. The experience of largeness emerges as a socially constructed disability in which many women are denied the opportunity to be fully healthy.

Ninty three yellowfin tuna, Thunnus albacares, the fork length ranged from 80 to 168 cm were collected from the waters around Seychelles by two longline fishing vessels from April to December in 2006. The muscle and liver samples were analyzed for total mercury (THg) and organic mercury (OHg) concentrations.The concentrations of THg and OHg of the muscle were similar to previous studies. The concentrations of THg and OHg form the muscles and livers were positive-linearly regressed with the fish of Fork Length larger than 113 cm (big fish group), but only THg concentration of muscle was negative- linearly regressed 80- 112 cm (small fish group). Such patterns were first found in yellowfin tuna. It might be related to the ¡§growth rate¡¨ . Only one THg concentration of liver were over the standard set by the European Commission Decision (1 mg / kg THg wet wt.), other samples were in accordance with standard set by the European Commission Decision and the US-FDA food safty standard (1 mg / kg MeHg wet wt.). According to the dietary recommendations set by the Department of Health, Executive Yuan, yellowfin tuna can replace 86% animal protein source per week of people.

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This research evaluated photonic imaging devices for assessment of body size and shape. In aim one, laser imaging measurements of circumference, volume, and % fat were examined in 70 women. Bland-Altman analysis indicated minimal error in girth of the waist and hip by laser imaging as compared to tape measure (95% limits of agreement for waist, -2.02-2.29 cm; hip, -3.39-2.90 cm). Volume by laser imaging was related to hydrodensitometry (r = 0.99, p < 0.01), and % fat estimates were not significantly different from hydrodensitometry or dual energy X-ray absorptiometry (DXA) (3.95 ± 1.74, 32.54 ± 1.28, and 35.86 ± 1.06, respectively, p > 0.05). In aim two, 120 adults were evaluated via stereovision imaging. Stereovision was significantly related to volume by air displacement plethysmography (ADP) and hydrodensitometry (R² > 0.99, p < 0.01). However, Bland-Altman analysis indicated variations in body fat between stereovision and ADP (95% limits of agreement, -16.77-16.05 kg). Therefore, aim three was development of a prediction equation to estimate fat from 13 stereovision measurements of body size and shape. These parameters combined to form upper and lower body factor scores, which, with gender, predicted 88.6% of variation in fat mass by ADP (p < 0.01). The equation improved 95% limits of agreement from -16.77-16.05 kg via direct volume measurement to -11.47-8.45 kg compared to ADP. Finally, in aim four, a subset of 56 women from aim two was evaluated for visceral fat by magnetic resonance imaging (MRI). Visceral fat was compared to a new indicator of abdominal adiposity via stereovision imaging: central obesity depth. Central obesity depth was correlated with visceral fat, following adjustment for age and ethnicity (r = 0.75, p < 0.01). Additionally, each 1 cm rise in central obesity depth raised the odds of being in the high versus low visceral fat tertile (Odds Ratio 8.59, 95% Confidence Interval 1.33-55.63, p < 0.05). Thus, both laser and stereovision body imaging appear to be valid techniques for evaluation of body size and shape. Furthermore, central obesity depth is a promising new measurement for assessment of visceral adiposity. / text

The fitness of any evolutionary unit can be understood in terms of its two basic components: fecundity and viability. The trade-offs between these fitness components drive the evolution of a variety of life-history traits in extant multicellular lineages. Here, I show evidence that the evolution of germ-soma separation and the emergence of individuality at a higher level during the unicellular-multicellular transition are also consequences of these trade-offs. The transition from unicellular to larger multicellular organisms has benefits, costs, and requirements. I argue that germ-soma separation evolved as a means to counteract the increasing costs and requirements of larger multicellular colonies. Volvocalean green algae are uniquely suited for studying this transition since they range from unicells to undifferentiated colonies, to multicellular individuals with complete germ-soma separation. In these flagellated organisms, the increase in cell specialization observed as colony size increases can be explained in terms of increased requirements for self-propulsion and to avoid sinking. The collective flagellar beating also serves to enhance molecular transport of nutrients and wastes. Standard hydrodynamic measurements and concepts are used to analyze motility (self-propulsion) and its consequences for different degrees of cell specialization in the Volvocales as colony size increases. This approach is used to calculate the physical hydrodynamic limits on motility to the spheroid colony design. To test the importance of collective flagellar beating on nutrient uptake, the effect of advective dynamics on the productivity of large colonies is quantified. I conclude first, that when colony size exceeds a threshold, a specialized and sterile soma must evolve, and the somatic to reproductive cell ratio must increase as colony size increases to keep colonies buoyant and motile. Second, larger colonies have higher motility capabilities with increased germ-soma specialization due to an enhancement of colony design. Third, advection has a significant effect on the productivity of large colonies. And fourth, there are clear trade-offs between investing in reproduction, increasing colony size (i.e. colony radius), and motility. This work shows that the evolution of cell specialization is the expected outcome of reducing the cost of reproduction in order to realize the benefits associated with increasing size.

Understanding the processes responsible for gradients in biodiversity is a central goal of ecological research. In order to elucidate the processes responsible for community assembly and structure, it is useful to adopt a functional trait approach to community ecology. This is because species names provide little information regarding how constituent species interact. In addition, assembly rules based on species names are likely to become intractably complex with increasing species richness but rules based on traits can provide simple, broadly applicable. In turn, generality is gained by emphasizing functional traits. Here I first build from a previously published model that merged metabolic theory with a model of community evolution and assembly to derive a general assembly rule based on a continuous functional trait and compare this rule with a broad suite of empirical data (Chapter 1). However, linking metabolism to macroevolutionary rates and patterns has thus far been limited to non-ecological, static models. These models are not inconsistent with empirical data, but are relatively limited in their predictive ability (Chapter 2). I thus next develop a fully dynamic `metabolic theory of biodiversity' (MTB) that explicitly implements the qualitative framework proposed in Allen et al. (2007). With this model I examine the influence of temperature dependent mutation rate on speciation rate, extinction rate and species richness (Chapter 2). The model predicts a variable influence of temperature, but the processes responsible for this variation are not immediately clear. I subsequently conduct a detailed analysis elucidating the key processes that allow/constrain a strong influence of temperature dependent mutation rate on species richness (Chapter 3). In addition to mutation rate, temperature-dependent metabolism can influence ecological (feeding and mortality) and ecosystem (e.g. decomposition and in turn nutrient supply) rates. As such, I extend the model developed in chapters 1-3 to incorporate these additional temperature dependencies and derive predictions for the influence of temperature over species richness (Chapter 4).

According to traditional theory, superior competitive ability in plants generally requires a relatively large plant body size. Yet, within natural, crowded vegetation, most resident species are small, and species size distributions are right-skewed at virtually all scales. I aim to provide a potential explanation for this paradox: small species are able to coexist with and outcompete larger species because smaller species have greater ‘reproductive economy’—the ability for some seed production despite severe size suppression when under intense competition. Tracey and Aarssen (2011) found an isometric relationship between minimum reproductive threshold size (MRTS) and maximum resident plant size (MAX); however, a more accurate measure of maximum potential body size (MPBS) was needed (without competition), as typically the effects of competition are size-dependent. An isometric relationship, similar to Tracey and Aarssen (2011) was seen. Tracey and Aarssen (2011) also found that, contrary to the predictions of traditional theory, larger species were not more abundant (based on plot occupancy) in an old-field community. A more accurate measure of abundance was obtained by locating random 1 x 1 m plots and counting the number of ramets for each species in the plot. A significant negative relationship was seen between abundance and MRTS. This suggests that the most abundant plants in communities are not those that are bigger, or smaller, they are those with the smallest MRTSs. To test whether this relationship exists in other habitats, plots were located in different old-field, shrub-land and wood-land communities. Ramets for each species within the plots were counted, and the largest plant of each species was measured. Significant negative relationships between abundance and MAX plant body size were seen in the shrub-land and woodland sites; however, no relationship was detected in this old-field site. The data support the idea that smaller species have greater reproductive economy, but the mechanism remains unknown. These results suggest that a smaller plant body size results in more effective gene transmission into future generations in all habitat types and stages of succession and indicates a suggested paradigm shift in the predicted selection effects of competition on the evolution of plant body size. / Thesis (Master, Biology) -- Queen's University, 2012-07-30 11:56:23.999

Body size influences virtually all aspects of the autecology of material flow by organisms. Thus, size classes may be considered as alternatives to grouping by trophic level, function or taxonomy to describe the structure and function of communities. The general intent of this thesis is to assess the role of body size in the dynamics of radiophosphorus in the freshwater plankton. To calculate a priori estimates of the fluxes of phosphorus through size classes of plankton, the rates of assimilation and excretion of laboratory cultures of algae and cladocerans were measured, and regressed on body mass (W). In both groups, assimilation increased as W('0.75). The turnover of body phosphorus was described as a two-compartment system. The turnover rates of the small (2-5% of body P) fast turnover pool, the large (95-98%) slow turnover pool, and that of the body phosphorus fell proportionately to W('- 1/4) in algae and W('- 1/2) in zooplankton. Field tests of allometric models of radiophosphorus flow were conducted by following the redistribution of radioactivity among 11 size fractions of enclosed epilimnetic assemblages over 5 to 6 days. Concentration of the tracer in the biomass declined with size soon after addition and gradually shifted to a uniform distribution within 3 days. A model that makes no a priori assumptions as to the trophic structure of the system, i.e. all size classes are at the same trophic level, predicted these dynamics better than one that assumes trophic position to increase with size. Further analyses indicated that explicit treatment of the physiological allometry and size distribution of broad functional groups of plankton are needed to improve the descriptive power of the model further.

The first year of life is one of the main survival bottlenecks for many fish species. Individual traits affecting survival can be morphological, physiological or behavioural. Body size, growth rate and activity have all been found to affect fitness in different organisms. However, the effects of these traits on fitness in natural conditions and for underyearlings are poorly investigated. In this study we attempted to induce compensatory growth in laboratory conditions in natural populations of brown trout fry (Salmo trutta). It was performed by exposing the fry to a period of restricted resources followed by a period of refeeding. Two behavioural trials were conducted on each individual where activity level was scored. All fish were subsequently released in their native stream and recaptured after a month to check for survival. We found that high individual activity level in an open field context increased the probability of survival under natural conditions. The importance of body size for survival decreased over time, and thus, with fish size. Full compensation was detected in body condition, while only partly compensation in weight and no compensation in length were detected during the experimental periods. Our results suggest that a brown trout fry’s individual activity level is repeatable and can be an important trait for selection in nature. The instable interactions between activity and life-history traits indicate environmental effects on these interactions. Furthermore, if body size is not the only trait affecting survival, compensation in body structures may not be a fast response to increase fitness after a period of growth depression.