A study of the vapour phase pyrolysis and alkaline hydrolysis of chloroform

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The decomposition of chloroform at 510˚C was investigated in a continuous flow system, using nitrogen as the carrier gas. The main products of the reaction were hydrogen chloride, tetrachloroethylene, pentachloroethane and hexachloroethane; hydrogen and chlorine could not be detected. Neither the addition of a radical initiator (azobisisobutyroni trile) nor an inhibitor (phenol) affected the breakdown, and so we have rejected the idea that the main reaction mechanism is of a radical nature. From the results obtained by varying the surface to volume ratio of the reactor, the reaction appeared to be catalysed by the surface of the reactor, but pretreating the tube by steaming, soaking in water or EDTA solution did not affect the pyrolysis. The reaction appeared to be virtually unaltered when a tube made from very pure silica was used. Kinetic investigations showed that the reaction was first order with respect to chloroform, and exhibited an induction period. Carrying out the reaction in a carbonised tube resulted in a faster reaction, and an increase in the induction period. To account for the results obtained, a mechanism is suggested which involves the formation of a carbon polymer on the silica reactor. Chloroform could then be adsorbed onto the polymer where reaction could occur. In a carbonised tube a graphite-like carbon structure may begin to take over as the catalyst. The alkaline hydrolysis of chloroform was studied in aqueous 1,4-dioxane (32 % w/v), at 360C. The rate of disappearance of chloroform was followed by gas-liquid chromatography, whilst the sodium hydroxide concentration was determined by titration with dilute hydrochloric acid. The reaction was second order overall, first order with respect to each of the reactants. Data obtained at 25˚C, 31˚C, 36˚C and 41˚C was used to determine the activation parameters. Increasing the concentration of dioxane in the solvent decreased the reaction rate. The reaction showed a definite negative salt effect, sodium chloride exhibiting a greater effect than potassium nitrate. The reaction between deuterochloroform and sodium deuteroxide in deuterium oxide/dioxane was faster than the reaction in the corresponding proton system. Application of the Yagil approach suggested that the transition state is associated with seven water molecules. This led us to suggest an alternative mechanism for the reaction, involving nucleophilic attack by water on the trichloromethyl anion, formed by loss of a proton from chloroform. In order to apply the Yagil criterion the hydration number of diolane had to be determined; a value of 2.25 was obtained.Science Research Counci

Angler Response to Success in the California Salmon Sportfishery: Evidence and Management Implications

This paper examines effort responsiveness to success in the California salmon partyboat sport fishery. The management process in this important fishery involves setting target harvest levels for both commercial and sportfishing groups and then using closed seasons, restricted gear, and possession limits to dampen effective effort. An important component of the management process involves forecasting sportfishing effort and its effect on catch in order to advance-plan management actions. For want of better information, simple proportionality rules-of-thumb are used currently and this paper examines the plausibility of these. Some simple models forecasting aggregate angler participation and aggregate partyboat catch on a weekly basis are estimated across several different ports. Our findings suggest that anglers are responsive to recent success in several sports (elasticities up to + .5) and that angler participation affects catch with an elasticity exceeding unity. These results indicate that the simple rules of thumb currently in use could be in substantial error.Environmental Economics and Policy, Research Methods/ Statistical Methods, Resource /Energy Economics and Policy,

Factors influencing the likelihood of dietary compliance amongst people with diabetes

Diabetes is one of the greatest health pandemics to impact the global health system and despite concerted efforts by governments to manage and control it there is little respite from its rapid progression. At this point there is no known cure for diabetes, however many of its negative health impacts can be controlled or prevented through formal therapy, dietary modification and exercise. Of these, dietary modification is considered an important first step for positive diabetes management and therapy outcomes. Unfortunately, despite this knowledge and support provided by the health system to better manage dietary lifestyles, many people with diabetes are unable to carry out dietary modification regimens. Factors such as individual cognition; environmental factors; and biological factors (Nam et al. 2011; Schiøtz 2012) have been found to influence dietary behaviour among people with diabetes. Of these, cognitive factors are considered to be the major driving force influencing health behaviours (Bandura 1986; Frewer et al. 1996). The present study through literature review has found cognitively driven factors such as self-efficacy, food risk perception, food related lifestyles and usage of social support groups as key drivers found to influence the likelihood of dietary compliance amongst people with diabetes. However, up to date there are still inconclusive results from studies testing these factors (Nam et al. 2011; Schiøtz 2012), therefore the present study has attempted to close these research gaps by empirically testing these constructs in the present model. The analysis in this study was conducted in three Phases: I, II and III i.e. Analysis I, II and III, to which 3 models were tested and presented as Alternative Model 1, 2 and 3 respectively. The results for all three phases reveal that self-efficacy is a key factor to influence both social support usage and dietary compliance. Phases I and II revealed no significant mediation relationship between the usage of social support and the cognitive constructs in the model and dietary compliance which contradicts literature (Antonovsky 1974; Thoits 1985). Phase III was conducted to re-examine the Social Support Groups Usage construct and to test its role as a key driver in the model. Phase III showed a strong relationship between social support usage and the constructs of self-efficacy, food risk perception and food related lifestyles. Mixed outcomes were also found in some causal relationships in all three models from this study which supports literature (Bandura 1986; Frewer et al. 1996; Grunert, Brunsø & Bisp 1993), in that cognitive factors are multi-dimensional, situational and guided by a range of factors. Using a social marketing framework, the findings of this study are translated into likely useful recommendations for the health system and relevant diabetes support groups in Australia. A constant challenge for those working within the social marketing domain is understanding the motivations that drive food choice behaviour, this understanding is essential for the creation of effective message strategies to generate dietary behaviour modification (Luca & Suggs 2013). Therefore, by understanding the factors that influence dietary compliance amongst people with diabetes, this study will not only have impact for those working in the health care sector but it will also extend current literature in social marketing in support of health care marketing

Devouring the Gothic: food and the Gothic body

At the beginnings of the Gothic, in the eighteenth century, there was an anxiety or taboo surrounding consumption and appetite for the Gothic text itself and for the excessive and sensational themes that the Gothic discussed. The female body, becoming a commodity in society, was objectified within the texts and consumed by the villain (both metaphorically and literally) who represented the perils of gluttony and indulgence and the horrors of cannibalistic desire. The female was the object of consumption and thus was denied appetite and was depicted as starved and starving. This also communicated the taboo of female appetite, a taboo that persists and changes within the Gothic as the female assumes the status of subject and the power to devour; she moves from being ethereal to bestial in the nineteenth century. With her renewed hunger, she becomes the consumer, devouring the villain who would eat her alive. The two sections of this study discuss the extremes of appetite and the extremes of bodily representations: starvation and cannibalism

Design and Basic Verification of a Discrete Event Simulator for Glucose Metabolism in Human Beings

This thesis describes the design and basic verification of a discrete event simulator for glucose metabolism in human beings. The simulator implements the glucose metabolism related behavior of various organs in the human body and tracks the blood plasma glucose level as the human body goes through a sequence of diet and exercise events. The simulator can mimic insulin resistance in various organs as well as the loss of insulin production in the pancreas and the adverse impact of these changes on the metabolic behavior of various organs. Thus, the simulator can serve as a model for people with diabetes. Such a model can be immensely useful to study the impact of specific life style changes on a person with diabetes. This thesis describes the simulator design as well as the results of simulations that verify the basic correctness of the simulator. This simulator represents the result of a multi-year collaborative effort involving the author, her MS thesis advisor and several other students working with the thesis advisor

The Akulmiut: Territorial dimensions of a Yup'ik Eskimo society

Thesis (Ph.D.) University of Alaska Fairbanks, 1989This monograph is an ethnohistoric and ethnographic study of 19th and 20th century land and resource use of the Akulmiut, a Yup'ik-speaking Eskimo society that occupied the inland tundra region between the Yukon and Kuskokwim rivers of western Alaska. The study examines the relationship between the patterns of spatial organization and wild resource utilization and resource distribution. Ethnographic studies have shown there is considerable variability in socioterritorial organization, which according to one recent theory, applied to this study, can be accounted for by examining the distribution of critical food resources in terms of density and predictability. The Akulmiut were selected for this study because of their unique situation among Alaskan Eskimos in terms of their subsistence economy and geographic location. With an economy based on fishing, utilizing non-salmon species of the low, marshy moist and wet tundra ecosystems, the adaptation of the Akulmiut is distinct among Alaskan Eskimos. Using data for the Akulmiut, this study tests the hypothesis that a territorial system occurs under conditions of high density and predictability (in time and space) of critical resources. Between groups or societies, the Akulmiut exhibited a territorial system of land use and occupancy as predicted when critical resources are dense and predictable. The study found that the key resource species of whitefish (Coregonus sp.) and northern pike (Esox lucius) exhibited resource distribution parameters characterized as predictable in time and location and were abundant or dense. Spatial organization showed that all primary villages and storage and processing facilities were situated where pike and whitefish could be readily intercepted during their annual migrations. The Akulmiut maintained exclusive use through overt defense, but also by means of cultural principles of land and resource use, ceremonial activities, and naming conventions. Dispersion of the population at other times ensured maintenance of a broader area for use in harvesting another key resource, blackfish (Dallia pectoralis). Dispersion was an efficient means of signaling areas used by the group, but also served to monitor incursions throughout the territory. This type of analysis was found to hold promise for explaining the diversity of socioterritorial organization among Alaskan Eskimos

The Effect of Previous Hamstring Injuries on ACL Injury Risk

There are between 100,000 and 200,00 ACL injuries a year with 60% of the injuries being noncontact related. The hamstring muscles increase knee stability and decrease stress on the ACL by assisting in preventing anterior tibial translation. If the hamstring muscles are comprised, they are not able to reduce the load on the ACL, putting excess strain on the ligament. The purpose of this study was to determine if athletes with a prior hamstring injury are at a relative higher risk of ACL injury compared to athletes without hamstring injury. This retrospective study evaluated 274 unique players over 5.5-year period. The number of athletes with hamstring injuries, with ACL injury, and with both ACL and hamstring injuries were recorded into a data tables. The date of injury was recorded as well. Two by two contingency tables were used to calculate the relative risk ratios by dividing the number of athletes with a specific injury (injuries) by the total population. Zero individuals suffered an ACL tear following a hamstring injury Therefore, the relative risk of sustaining an ACL tear with a history of hamstring injury relative to risk of ACL injury without a history of hamstring injury was 0.16 (95% CI= 0.01, 2.63). p=.198. Five individuals were found to have suffered a hamstring injury following an ACL injury; therefore, the relative risk was 1.25 (95% CI= .59,2.63). p=.57. The study reflects that individuals with a previous hamstring injury are not at higher relative risk of ACL injury compared to those without a history of hamstring injury

A Low-Profile Subsistence Fishery: Pike Fishing in Minto Flats, Alaska

Subsistence research in contemporary communities in rural Alaska is revealing the important contribution of fish species other than salmon to the food supply, yet the subsistence use of non-salmon species has had a low profile in management and regulatory regimes of the fisheries in Alaska. Management concerns arose when a developing northern pike (Esox lucius) sport fishery occurred in an area with preexisting subsistence uses of pike stocks. The Minto Flats subsistence pike fishery has been part of Minto village's subsistence economy throughout the century, whereas sport fishing for pike in Minto Flats is comparatively recent, coinciding with the growth of the nearby regional center of Fairbanks. The identification of a preexisting subsistence fishery combined with field research to record harvest levels, geographic areas used, and seasonality of harvest contributed to a management plan that enabled conservation and harvest of the resource. Knowledge about the subsistence fishery allowed regulations to be established that provided for compatible uses of the pike fishery by subsistence and sport fishermen by segregating the fisheries in time and place and employing standard management tools.Key words: subsistence fisheries, food fisheries, sport fisheries, northern pike, Esox lucius, fisheries management, AlaskaMots clés: pêche de subsistance, pêche reliée à l’alimentation, pêche sportive, grand brochet, Esox lucius, gestion des pêcheries, Alask

Foraging for a foothold: Causes and consequences of dietary variation in a threatened avian pollinator

Foraging is a central theme in ecology and underlies some of the most fundamental interactions among species. While diet has long been treated as uniform within species, a paradigm shift is now taking place as ecologists recognize that individuals vary. However, questions remain about why this intraspecific variation exists and what consequences it may have for individuals, populations, and ecosystems. This information may be particularly important for species that are threatened due to food limitation, as dietary variation could be used to inform conservation efforts. In this thesis, I used the hihi (Notiomystis cincta), a threatened New Zealand passerine, as a case study to explore the causes and consequences of dietary variation and possible implications for conservation. Because observing threatened species is often difficult in the wild, I first developed methodology to obtain more reliable dietary estimates from limited foraging observations. Using these improved metrics, I found that individual hihi specialize within the broader species diet. Generalists survived better than specialists, suggesting that dietary specialization may have consequences for fitness. I next explored whether an array of intrinsic and extrinsic factors could explain dietary variation. Results suggested a weak correlation between diet and sociality, so I then conducted an experiment to test how directly altering the social environment affects diet. Using two scheduled conservation translocations, I found that individual hihi shifted towards more generalist diets when they were moved from a highly competitive source site to a less competitive release site. This suggests hihi share the same inherent dietary preferences but must specialize to avoid competition in dense populations. Furthermore, individuals that were more generalist before the translocation were more likely to be seen five months later, but only if they remained at the source site; at translocated sites, generalists tended to be less likely to be seen than specialists. These results suggest that selectively translocating specialists may improve translocation success without jeopardizing the source population. Finally, I investigated how foraging behavior can shape the environment. Hihi are pollinators of several threatened native plant species, so conservation of hihi could promote ecosystem recovery as well as species recovery. However, little is known about how effectively hihi translocations restore lost pollination function and whether individuals vary in their pollination abilities. Through a multi-site pollinator exclusion experiment, I found that ecosystems may be able to partially adapt to the loss of hihi. Nevertheless, hihi bring unique benefits to pollination by improving seed quality. There was also some evidence that individual hihi vary in their efficiency as pollinators. Together, my findings demonstrate that foraging is inextricably linked to the environment: the ecosystem shapes individual variation, which, in turn, shapes ecological functions. A better understanding of dietary variation may also have important implications for threatened species and ecosystems, informing the design of conservation interventions.Gates Cambridge Trus