85,898 results

  • Glargine as a Basal Insulin Supplement in Recovering Critically Ill Patients - An In Silico Study

    Razak, N.N.; Lin, J.; Chase, J.G.; Shaw, G.M.; Pretty, C.G.; Le Compte, A.J.; Suhaimi, F.M.; Jamaludin, U. (2010)


    University of Canterbury Library

    Tight glycaemic control is now benefiting medical and surgical intensive care patients by reducing complications associated with hyperglycaemia. Once patients leave this intensive care environment, less acute wards do not continue to provide the same level of glycaemic control. Main reason is that these less acute wards do not have the high levels of nursing resources to provide the same level of glycaemic control. Therefore developments in protocols that are less labour intensive are necessary. This study examines the use of insulin glargine for basal supplement in recovering critically ill patients. These patients represent a group who may benefit from such basal support therapy. In silico study results showed the potential in reducing nursing effort with the use of glargine. However, a protocol using only glargine for glucose control did not show to be effective in the simulated patients. This may be an indication that a protocol using only glargine is more suitable after discharge from critical care.

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  • Sex In The City: Young Men's Experience of Body & Identity Construction

    Hillgrove, Craig (2014)

    Masters thesis
    University of Otago

    This research contributes to the scholarly fields of sport and health sociology and their parent discipline sociology by exploring the phenomenological experiences of three young men living in Sydney, Australia (aged 20-25). I examine how they construct and (re) construct their selves through various bodily practices (e.g. exercise, diet, grooming) to achieve the ‘ideal’ male body and persona during their early adulthood lives. Informed by a social constructionist perspective, I explore these young men’s experiences of their bodies using ethnographic research methods (e.g. life histories, visual diaries, interviews and surveys) and draw on a variety of theoretical resources particularly those in relation to Crossley’s (2005) reflexive body techniques, which encompas Bourdieu’s concepts of capital, habitus and field and Merleau Ponty’s theory of phenomenology of perception. I also explore the various social structures that influence the choices the young men make in changing their physiques and the effects these have on their health and well-being. Whilst acknowledging that these individuals have a sense of agency in choosing the kind of body and identity that they want to create, their perceived sense of agency is inevitably influenced by the discourses circulating within the contexts in which they live. These discourses include those derived from sport, health and medicine, masculinity, politics/government, education, class, sexuality and the media. Futher, the growth of the sports supplementation industry, the growth of the fitness and gym industry, the rise of the naked/semi naked ‘aestheticathletic’ male body in the media, the use of image enhancing drugs like steroids, illegal drug trade and importation of drugs, increased mental health issues and the increased rates of selfharm are phenomena that can and do shape how young men feel about their bodies and the practices they choose to engage in to shape them up. This thesis affords a unique glimpse into the day to day reflexive body techniques of three young men, and argues that their personalities, thoughts, bodies and identities exist within within a complex multidimensional social web, which ultimately influences how their biological embodied self can be rejected, (re) structured, hidden, constrained, controlled and presented.

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  • A web-based dietary assessment method for exploring zinc bioavailability: Developing a food list and pre-testing

    Luey, Catherine Anne (2014)

    Masters thesis
    University of Otago

    Background: Zinc is an essential trace element that contributes to many different biological functions. Inadequate dietary zinc intakes play an important role in zinc deficiency in premenopausal women, so a dietary assessment tool has been developed to assess usual zinc intake. The Web Meal-Based Intake Assessment Tool (Web-MBIAT) described in this study is an internet-based dietary assessment tool that assesses individuals’ usual intake of zinc and its absorption modifiers by meal, over the past month. Aims: The aim of the research project was to compile a food list designed to measure intakes of zinc and its absorption modifiers for the Web-MBIAT, and pilot and pre-test the Web-MBIAT in a sample of premenopausal, adult women to assess ease of use. Design: Food items were included in the main food list if they contained ≥0.5mg zinc/100g or ≥50mg phytate/100g. Food items were also included if they were part of a food group which contributed ≥3% zinc or ≥6% phytate to the diet of the target audience. The food list was incorporated into the Web-MBIAT which was then pilot and pre-tested with 10 premenopausal adult women in Dunedin, New Zealand. Results: A total of 467 of the 2710 foods in FOODfiles 2010 Version 02, were included in the main food list. Participants found the Web-MBIAT relatively easy to use giving it a mean score of 8.2 (on a scale of 1 to 10, with 10 being the easiest) when asked to score how easy the Web-MBIAT was to complete. Participants found quantifying portion sizes the most difficult part of completing the Web-MBIAT. Participant suggestions to improve ease of use included adding more measure descriptors, recording what was consumed the week before completing the Web-MBIAT, having physical or visual examples of portion sizes, and providing the participants with a list of all the food items in the Web-MBIAT during the interview. Conclusion: Piloting and pre-testing of the Web-MBIAT revealed that participants found it relatively easy to complete, but several improvements need to be made, particularly concerning quantifying portion sizes, to improve performance and ease of use before validation in the future.

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  • Measuring Baby-Led Weaning: Method development and pilot testing

    Schramm, Claire Julia (2014)

    Masters thesis
    University of Otago

    Background: Baby-Led Weaning (BLW) is an alternative approach to complementary feeding in which infants are encouraged to self-feed using whole family foods from the start of solids introduction, rather than being spoon-fed purées by their parents. While research suggests that BLW may be feasible for the majority of families, health professionals remain concerned with the potential risks of choking, iron deficiency, and inadequate energy intake. Further research into the implications of BLW is needed to provide both health professionals and policy makers with sound scientific evidence on which to base their advice. However, in the limited research to date, there has been no agreement as to how to measure BLW. Therefore, for research to progress in this area, a standard measure of BLW needs to be developed to enable accurate and comparable results to be generated. Aim: To develop, pre-test and subsequently pilot test 2-4 methods to measure the extent of baby-led complementary infant feeding practices, in order to provide an effective tool for measuring and describing the level of adherence to BLW for future research studies. Methods: To capture the holistic nature of BLW, six components were identified from the literature. These components were then measured using four methods: Retrospective Questionnaire (RQ), Weighed Food Record (WFR), End of Day Questionnaire (EDQ) and Early Childhood Education Food Record (ECEFR). The RQ, WFR and EDQ were pretested in focus groups with mothers who had previously used BLW, and then pilot tested over a 24- hour period with mothers currently following either BLW or Traditional Weaning (TW) practices with their child. The ECEFR was pretested in interviews with Early Childhood Education (ECE) centre staff. Results: Participants identified key issues in the RQ such as the interpretation of various questions and issues with memory recall. In the WFR and ECEFR, participants suggested where layout, instruction and example changes were needed to improve clarity. Pilot testing identified the need for a more conveniently sized ‘Away From Home’ booklet for participants to use when out of the house and unable to weigh foods for the WFR. The EDQ needed both structural and wording revisions. The three pilot-tested methods, the RQ, WFR and EDQ, were able to clearly distinguish between the BLW and TW groups in the level of self-feeding, form of food offered, extent of family meal times, extent to which the same family foods were offered, level of exclusive and on demand breastfeeding, and the age of solids introduction. Conclusion: This pilot study describes four novel methods capable of measuring the six key components of BLW. These methods enable users to characterise BLW as a whole, thereby more closely reflecting its holistic nature. They also provide a range of measurements of BLW that future studies can use to assess adherence to BLW practices among participants, rather than relying on self-reported BLW status. This will ensure more robust and comparable results on the health outcomes of BLW practices in future studies.

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  • Are outdoor spaces important? An investigation into the provision of outdoor space for medium density housing developments

    Gray, Katrina Jane Rhiannon (2014)

    Masters thesis
    University of Otago

    The provision of a large backyard, the ‘quarter acre dream’, has historically been a key feature of housing development throughout New Zealand. However, in Auckland, due to a rapidly increasing population, rising housing prices and housing policies aimed at intensification, housing density is increasing. Medium density housing has emerged as a key housing form which provides an affordable option compared with stand-alone housing and provides a wide variety of housing and outdoor space types. Medium density housing is generally associated with decreasing private outdoor space. A related change is the increasing number of communal outdoor spaces. As private and communal outdoor spaces change, so too does the use and value of public outdoor space. Given the importance of outdoor space, this study seeks to examine the changing provision of outdoor space in medium density housing developments. Albany is a rapidly developing area of Auckland which already has a significant number of medium density housing options and is predicted to have many more as it develops. Therefore, the focus for this research is on medium density housing developments in Albany. This research found that, generally, the current provision of outdoor spaces is working well. There was increasing demand for medium density housing due to issues of affordability and schooling, as well as an ethnic relationship. Private, communal and public outdoor spaces were considered to be important for residents and are used for a range of recreational and social activities. Interestingly, each type of outdoor space provides for different uses and needs. Nonetheless, the most important form for residents was private outdoor space. This research also found that the size of residents’ private outdoor space is already, or is likely to be compensated for by communal or public outdoor spaces. Complete compensation of private outdoor space is not likely as communal and public outdoor spaces are not able to offer the privacy which private outdoor spaces afford. Overall, resident satisfaction with their outdoor spaces was high, however, there was a diversity of responses. The diversity of responses shows the importance of providing a wide range of housing and outdoor space types, so that the housing needs of a variety of residents are achieved.

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  • Phytate and Zinc intakes of New Zealand toddlers aged 12-24 months

    Hartley, Nicola Kate (2014)

    Masters thesis
    University of Otago

    Statement of the problem: Phytate is primarily found in cereals and legumes and is the major inhibitor of zinc absorption. The United States of America, Australia and New Zealand currently have no information regarding the phytate content of food items in their food composition databases because most studies have been completed in developing countries where the phytate intake is high and zinc deficiencies have commonly been reported. A recent study in Otago, New Zealand, found that serum zinc concentrations of toddlers were low despite the toddlers having an adequate intake of zinc. The current study aimed to assign phytate values to mixed dishes and to other food items in the New Zealand food composition database, FOODfiles, that had not already been assigned phytate values by an earlier Master of Dietetics student, and to use this information to determine whether phytate is likely to be affecting zinc absorption in toddlers who were 12-24 months of age. Methods and procedures: The Candidate assigned phytate values by using values from published literature and by developing recipes for mixed dishes. The developed recipes were adjusted for yield factors and, where appropriate, for fermentation. Previously assigned phytate values were adjusted for the extraction rate of New Zealand white flour and all phytate values were checked and corrected for accuracy. The dietary intakes of 154 toddlers from Wellington, North Canterbury and Dunedin who were 12-24 months of age had previously been collected as part of the Eating Assessment in Toddlers study by using five-day weighed diet records. The Candidate used this information to determine the phytate and zinc intakes of the toddlers and to calculate the phytate:zinc molar ratio. Results: A total of 906 phytate values were assigned to food items in FOODfiles including values for 453 recipes developed for mixed dishes. Overall, 6.5% of the toddlers had a zinc intake below the Estimated Average Requirement of 2.5mg per day, however, significantly more South Island toddlers (15%) had a zinc intake below 2.5mg per day compared to North Island toddlers (4%) (P=0.0091). A total of 7% of the toddlers had a phytate:zinc molar ratio above 15 for their overall diet, but 59% (of the subset of participants tested) had a phytate:zinc molar ratio above 15 at ‘breakfast’. The major sources of phytate in the toddlers’ diets were bread (27%) and breakfast cereals (23%). The major sources of zinc in the toddlers’ diets were dairy products (26%) and meat (11%). The majority of toddlers in this study were New Zealand European (77%) with 8% identifying as Māori and 3% identifying as Pacific Island. More toddlers were from the least deprived areas of New Zealand than the most deprived areas. Conclusions: There is now an electronic version of the New Zealand food composition database which includes phytate values for all food items. Most of the toddlers from this study appear to have an adequate zinc intake, and it appears that their overall intake of phytate is unlikely to be inhibiting their zinc absorption. However, there is some suggestion that zinc absorption from ‘breakfast’ may be impaired for more than half the participants because the phytate:zinc molar ratio is so high for that meal. Biochemical testing of serum zinc concentration was not carried out in this study but would be warranted based on the findings of this study.

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  • Impact of variation in patient response on model-based control of glycaemia in critically ill patients

    LeCompte, A.J.; Chase, J.G.; Shaw, G.M.; Lin, J.; Lynn, A.; Pretty, C.G. (2010)


    University of Canterbury Library

    Critically ill patients commonly experience stress-induced hyperglycaemia, and several studies have shown tight glycaemic control (TGC) can reduce patient mortality. However, tight control is often difficult to achieve due to conflicting drug therapies and evolving patient condition. Thus, a number of studies have failed to achieve TGC possibly due to use of fixed insulin dosing protocols over adaptive patient-specific methods. Model-based targeted glucose control can adapt insulin and dextrose interventions to match identified patient sensitivity. This study explores the impact on control of assuming patient response to insulin is constant versus time-varying. Simulated trials of glucose control were performed on adult and neonatal virtual patient cohorts. Results indicate assumptions of constant insulin sensitivity can lead to significantly increased rates of hypoglycaemia, a commonly cited issue preventing increased adoption of tight glycaemic control in critical care. It is clear that adaptive, patientspecific, approaches are better able to manage inter- and intra- patient variability than typical, fixed protocols.

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  • Relationship between the intake of total flavonoid and flavan-3-ols, and 5-year cardiovascular disease risk scores in New Zealand adults

    Sim, Kirsten (2014)

    Masters thesis
    University of Otago

    Objective: The aim of the study was to expand the New Zealand Food Composition Database (NZFCD) to include flavonoid data, in order to determine the relationship between the intake of (a) total flavonoids and (b) flavan-3-ols, and 5-year cardiovascular disease (CVD) risk score in New Zealand adults. Design: The present study used data from the New Zealand Adult Nutrition Survey (NZANS) 08/09 - a national population-based nutrition survey, conducted in a sample of 4271 participants. Flavonoid and Flavan-3-ol intake was assessed using 24-hour food recalls. Data on blood pressure, lipid status, diabetes status (HbA1c), smoking status, ethnicity, age and gender were used to determine 5-year CVD risk scores. Each food in the FOODfiles dataset of the NZFCD was updated using the flavonoid databases: USDA and Phenol explorer. To determine the relationship between flavonoid intake and CVD risk, logistic regression was used to investigate relationships between categories of X intake with categories of CVD risk. Results: Those in the high total flavonoid intake category were less likely to have a high CVD risk score than those with a low total flavonoid intake, after adjustment for age, body mass index (BMI), sex, ethnicity and New Zealand Deprivation Index (NZdep). Similarly, those with a high intake of flavan-3-ols were less likely to have a high CVD risk score. Those with a low intake of flavan-3-ols, were more likely to have a high CVD risk score. Foods that contributed most to the quantitative intake of flavan-3-ols were sugar/sweets, fruit, alcoholic and non-alcoholic beverages. Conclusions: New Zealand adults with a higher intake of total flavonoids and in particular flavan-3-ols are likely to have a lower CVD risk score. Therefore, consuming foods higher in flavan-3-ols, such as cocoa products, fruit and tea, may help to reduce the risk of developing CVD, as long as a balanced diet is followed.

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  • Evaluation of the Performances and Costs of a Spectrum of DIST Protocols

    Docherty, P.D.; Chase, J.G.; Lotz, T.F.; Hann, C.E.; TeMorenaga, L.; McAuley, K.A.; Shaw, G.M.; Berkeley, J.E,; Mann, J.I. (2010)


    University of Canterbury Library

    The strategic design of most insulin sensitivity (SI) tests maximises either accuracy or economy, but not both. Hence, accurate, large-scale screening isn’t feasible. The DIST was developed to better optimize both important metrics. The highly flexible DIST protocol samples insulin, glucose and C-peptide during a comparatively short test. Varying the sampling periods and assays, and utilising alternative computational methods enables a wide range of tests with different accuracy and economy tradeoffs. The result is a hierarchy of tests to facilitate low-cost screening. Eight variations of the DIST are evaluated against the fully-sampled test by correlating the SI and endogenous insulin production (Uen(t)) metrics. Five variations include sample and assay reductions and three utilise DISTq parameter estimations. The DISTq identification methods only require glucose assays and thus enable real-time analysis. Three DISTq methods were tested; the fully-sampled, the Short, and the 30 minute two-sample protocol. 218 DIST tests were completed on 84 participants to provide the data for this study. Methods that assayed insulin replicated the findings of the full DIST particularly well (R=0.89~0.92) while those that assayed C-peptide managed to best replicate endogenous insulin metrics (R=0.72~1.0). The three DISTq protocols correlated to the fully-sampled DIST at R=0.83, 0.77 and 0.71 respectively. As expected, test resolution increased with rising protocol cost and intensity. The ability of significantly less expensive tests to replicate the values of the fully-sampled DIST was relatively high (R=0.92 with four glucose and two insulin assays and 0.71 with only two glucose assays). Thus, an SI screening programme could achieve high resolution at a low cost by using a lower resolution DIST test. When an individual’s result is close to a diagnostic threshold stored test samples could be re-assayed for more species to allow a higher resolution analysis without the need for a second invasive clinical test. Hence, a single test can lead to several outcomes with this hierarchy approach, enabling large scale screening with high resolution only where required with minimal and feasible economic cost and only a single invasive clinical procedure.

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  • A Fast and Accurate Diagnostic Test for Severe Sepsis Using Kernel Classifiers

    Parente, J.D.; Lee, D.S.; Lin, J.; Chase, J.G.; Shaw, G.M. (2010)


    University of Canterbury Library

    Severe sepsis occurs frequently in the intensive care unit (ICU) and is a leading cause of admission, mortality, and cost. Treatment guidelines recommend early intervention, however gold standard blood culture test results may return in up to 48 hours. Insulin sensitivity (SI) is known to decrease with worsening condition and inflammatory response, and could thus be used to aid clinical treatment decisions. Some glycemic control protocols are able to accurately identify SI in real-time. A biomarker for severe sepsis was developed from retrospective SI and concurrent temperature, heart rate, respiratory rate, blood pressure, and SIRS score from 36 adult patients with sepsis. Patients were identified as having sepsis based on a clinically validated sepsis score (ss) of 2 or higher (ss = 0–4 for increasing severity). Kernel density estimates were used for the development of joint probability density profiles for ss = 2 and ss < 2 data hours (213 and 5858 respectively of 6071 total hours) and for classification. From the receiver operator characteristic (ROC) curve, the optimal probability cutoff values for classification were determined for in-sample and out-of-sample estimates. A biomarker including concurrent insulin sensitivity and clinical data for the diagnosis of severe sepsis (ss = 2) achieves 69–94% sensitivity, 75–94% specificity, 0.78–0.99 AUC, 3–17 LHR+, 0.06–0.4 LHR-, 9–38% PPV, 99–100% NPV, and a diagnostic odds ratio of 7–260 for optimal probability cutoff values of 0.32 and 0.27 for in-sample and out-of-sample data, respectively. The overall result lies between these minimum and maximum error bounds. Thus, the clinical biomarker shows good to high accuracy and may provide useful information as a real-time diagnostic test for severe sepsis.

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  • Phytate and zinc intakes of toddlers from the South Island of New Zealand aged 12-24 months

    Chang, Megan Meng-Hsin (2014)

    Masters thesis
    University of Otago

    Up to 40% of New Zealand (NZ) toddlers have low serum zinc concentrations. This could be a result of low intakes of zinc and high intakes of phytate in the diet. Phytate is a known inhibitor of zinc absorption and is found in foods such as cereals and legumes. Currently, there are no data on the phytate contents of foods in the New Zealand food composition database, FOODfiles; therefore the amount of phytate consumed by toddlers cannot be determined. The aim of this study was to compile phytate values for individual foods (i.e., not mixed dishes) in the NZ food composition database, then use these values to calculate the phytate and zinc intakes of South Island New Zealand toddlers aged 12-24 months. International research papers investigating the phytate content of foods were identified. To adjust these values specifically for New Zealand foods, various calculations were required. These included adjusting phytate values of foods in the literature when the moisture content of foods in FOODfiles was different to that in the literature, and also converting phytate values per dry weight given in the literature into phytate values per wet weight which was the required format for FOODfiles 2010. As the study aimed to examine phytate intakes of South Island toddlers, additional foods not in FOODfiles 2010 and recipes consumed by the toddlers were also assigned phytate values. The Eating Assessment in Toddlers (EAT) study collected five day weighed food records and were entered into Kai-culator, a dietary assessment programme. The phytate values assigned by the candidate were loaded into Kai-culator so the phytate and zinc intakes of the South Island toddlers participating in the EAT study could be determined. A total of 2400 foods were assigned a phytate value. The majority of South Island participants in the EAT study were “New Zealand European and Other” (92.3%), with a median energy intake of 3621 kJ/day, a median phytate intake of 325 mg/day, and a median zinc intake of 4.2 mg/day. Fifteen percent of toddlers had inadequate zinc intakes, and calculation of the phytate: zinc molar ratio showed that 5% of South Island toddlers were classified as having diets with low zinc absorption levels. The main sources of phytate in the toddlers’ diets were bakery products (35.5%) and breakfast cereals (21.7%). These New Zealand toddlers had similar phytate intakes to toddlers in other developed western countries, and most of the toddlers had adequate zinc intakes. Although zinc intakes of NZ toddlers were lower than those from the US, this was likely due to zinc fortification in US breakfast cereals. As no blood samples were collected in the EAT study, serum zinc concentrations could not be determined, so the effect of these zinc and phytate intakes on serum zinc concentrations remains unknown. Until the phytate content of foods in FOODfiles 2010 can be determined through chemical analysis, the values assigned to foods in the current study are the best data available on the phytate contents of foods in the New Zealand food supply.

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  • Improving Captive Maintenance Techniques for New Zealand Native frogs (Leiopelma spp.)

    Shaw, Emma (2014)

    Masters thesis
    University of Otago

    The captive maintenance of healthy amphibian species requires an in depth knowledge of their dietary and environmental requirements. In New Zealand, only three of the four threatened native frog species within the genus Leiopelma are held in captivity. Each of these captive populations has suffered significant rates of disease and mortality, coupled with poor breeding success. To determine the suitability of current captive maintenance techniques used for Leiopelma, this thesis examined the differences between natural Leiopelma diets and environments and those provided to frogs in captivity. Chapter 2 completes the most thorough dietary analysis of wild L. hochstetteri to date, identifying 23 different prey groups in 73 faecal pellets. Potential prey items were sampled using pitfall traps and this showed monthly variation that was significantly different to the composition of the diet. Different age classes were found to eat similar prey groups in different frequencies. The results of the faecal pellet study were used to formulate a captive diet for juvenile L. hochstetteri. The diet analysis in Chapter 2 is followed by an investigation into the nutritional qualities of both invertebrates found in the natural diet of Leiopelmaand those fed to this genus in captivity (Chapter 3). Importantly, the diet of wild frogs was found to contain invertebrates which were rich in calcium and had positive calcium to phosphorus ratios. These attributes were lacking in all but one of the invertebrate species fed to captive frogs, meaning that current diets are likely to hinder bone growth and development and require amendment. In order to inform dietary improvement, the efficacy of using the isopod Porcellio scaber to naturally increase calcium content in the diet of Leiopelma was assessed. This was made possible through a novel analysis of gut-retention time in L. archeyi, L. hochstetteri and L. pakeka. Calcium in P. scaber was found to be bioavailable to each Leiopelma species examined, with the highest calcium absorption occurring in L. archeyi and the lowest in L. pakeka. Porcellio scaber should thus be fed to all Leiopelma in captivity. Faecal analysis found that L. hochstetteri at Hamilton Zoo consume invertebrates which are self-introduced to their enclosures, indicating that their diet may be more nutritionally complete than previously assumed. Further recommendations on ways to improve the diets of captive Leiopelma are presented at the end of Chapter 3. The designs of Leiopelma enclosures need to be assessed to ensure that they closely mimic the abiotic parameters of frogs’ natural habitats. Chapter 4 compared aspects of the microhabitats of wild Leioplema at Tapu, to those observed in Hamilton and Auckland Zoo enclosures. These included water and soil composition, annual changes in water and air temperature as well as relative humidity, and UV-B irradiance. The study also examined retreat site composition and age class associations within L. hochstetteri. Captive enclosures were shown to provide abiotic parameters close to those observed in natural Leiopelma habitat. Improvements that may further enhance the health and breeding success of captive Leiopelma are outlined.

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  • Documenting lives over time: How longitudinal documentaries provide a visual life course perspective

    Miller Skillander, Katherine (2014)

    Masters thesis
    University of Otago

    The term longitudinal documentary has become commonplace in film studies where it is used to describe any series of documentaries made over a long period of time; this thesis explores the origins of the word ‘longitudinal’ in other disciplines. In a scientific longitudinal study the same group of people are observed over time with points of interest being collected at repeated intervals. Multidisciplinary researchers often adopt a life course perspective that understands lives as taking the shape of a path that is not straight or static, but rather has both continuity and change. The concept of the whole person is also used to express a sense of individuality, as life course researchers look at lives as ‘a whole’, rather than through universal separate stages. By importing the concepts of the life course and the whole person in this thesis, I will argue that longitudinal documentaries can be seen as providing a uniquely visual life course perspective. Three longitudinal documentaries, the Seven Up series (1964-2012), the Love, Lust and Lies series (1975-2009) and Women/Sheilas (1976 & 2004), are analysed so as to explore the exceptional features of longitudinal documentary. Chapter One focuses upon the emergence of the longitudinal documentary form. It traces how this form has evolved since the first longitudinal documentary in 1964 and establishes the special relationship to time that such documentaries exhibit. The three chapters that follow then break down how longitudinal documentaries document their participants over time, focusing on three temporalities: historical time, biological time and biographical time. Chapter Two uses historical time as a framework to discuss the representation of outer time through objective elements such as the revisit and different temporal activities of looking back (retrospectively) and forwards (prospectively). Chapters Three and Four will explore the more subjective qualities of inner time through biological time and biographical time. Biological time is represented in a person-centred approach via close ups on the face while biographical time is represented through the interview. The fusion of historical, biological and biographical time in longitudinal documentary provides an unprecedented ‘visual life course perspective’.

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  • Defining the mechanism of NAD-mediated mutagenesis

    Ferguson, Shaun (2014)

    Masters thesis
    University of Otago

    Bacteria require the ability to rapidly evolve and adapt in order to overcome the physiological stresses that they often face. Genetic variation and natural selection drive adaptive mutation, however the mechanism behind adaptive mutation is controversial. A novel discovery indicated adaptive mutation, through hypermutation, occurs in Mesorhizobium loti. Mesorhizobium loti is an α-proteobacterium and is a nitrogen-fixing microsymbiont of several Lotus species. The investigations for this study were carried out using three M. loti strains: M. loti R7A, M. loti R7ANS and M. loti R7Adct. M. loti R7A contains a mobile symbiosis island, ICEMlSymR7A, M. loti R7ANS is a non-symbiotic derivative of R7A that lacks ICEMlSymR7A, and M. loti R7Adct contains a deletion of the otherwise-functional C4-dicarboxylate transport system that is encoded on ICEMlSymR7A. These strains contain a non-functional (cryptic) C4-dicarboxylate transport (dct) system on their chromosome and thus they are unable to grow on media with succinate as a sole carbon source. However when cultured on such media, a sub-set of the strains give rise to Dct+ colonies over time that contain mutations that activate the cryptic dct genes. This ability to mutate was found to be due to nadQABC genes located on the mobile symbiosis island, ICEMlSymR7A. It was found that in the presence of the nadQABC locus, or of a large excess of nicotinic acid (NA), the Dct- non-symbiotic mesorhizobia and strain R7Adct give rise to Dct+ mutants over time. Strains lacking the nadQABC genes and grown in the presence of low concentrations of NA never give rise to Dct+ mutants. Furthermore the mutants seem to arise only after growth has stopped. Mutagenesis under non-growing conditions is known as stress-induced mutagenesis (SIM) or stationary-phase mutagenesis. The purpose of this study was to investigate the hypothesis that the Dct+ mutants arise as a result of oxidative DNA damage. We propose that hypermutation should result in accumulation of mutations in the genome due to oxidative stress caused by an imbalance in NAD homeostasis and that potentially deleterious mutations will be repaired. In this study, a series of single gene insertion duplication mutants (IDM) and a markerless deletion mutant were constructed for genes involved in DNA repair and in oxidative stress tolerance. It was hypothesised that these mutants would show an increase in both deleterious and beneficial mutations. The genes that were targeted encode proteins involved in the GO repair system (MutM, MutT, MutY) and Mismatch Repair (MMR) system (MutS) as well as a monofunctional catalase (KatE) and a bifunctional catalase/peroxidase (KatG). Mutants in each of the genes were constructed in M. loti strains R7A, R7ANS and R7AΔdct by either insertional duplication mutagenesis or in-frame deletion and mutants confirmed via PCR and Southern hybridisation techniques. The mutants in the R7ANS and R7A∆dct backgrounds were assayed for mutator phenotypes in the presence or absence of an excess of NA. The results demonstrated a considerable increase in mutation rate for the katG, mutS, mutT and mutY mutants, while the katE and mutM mutants showed wild-type mutation rates. Overall, these results provide compelling evidence for a mechanism whereby under conditions of stress, elevated levels of ROS and NADH lead to HO• formation via the Fenton reaction. This damage leads to wide-spread mutation resulting in both deleterious and beneficial mutations. The deleterious mutations are constantly repaired, and when a beneficial mutation occurs, the conditions of stress are alleviated, removing the source of SIM and restoring mutation rates to their original state.

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  • A comparison between the effects of a whey protein drink and trim milk on rehydration after exercise in the heat.

    Robinson, Caleb James (2014)

    Masters thesis
    University of Otago

    Background: Beginning an exercise session euhydrated is important for performance and health. Rapid and adequate rehydration is important for many athletes, especially those partaking multiple sessions of exercise each day, or those involved in weight category sports. The macronutrient and electrolyte concentration of the fluid ingested following exercise can affect the amount retained within the body and so can influence hydration status. However, the optimal rehydration beverage composition is currently unknown. Electrolytes and carbohydrates have been thoroughly studied, however the role of protein in rehydration is yet to be determined. Objective: To compare the effect of a commercially available whey protein beverage against trim milk, in terms of rehydration after exercise induced dehydration. Design: Ten healthy active males aged 23.1 (1.5) years provided written informed consent prior to participating in the study. All trials commenced between 17:30 and 18:00 hours and were separated by at least one week. For the two trials, participants cycled in the heat (35oC and 65% RH) until 1.89 ± 0.36% of their body mass was lost. They then consumed either whey protein or trim milk in a randomised order replacing 150% of body mass losses in the hour post-exercise. Urine samples were collected pre-exercise, 1 hour post, 2 hours post, and first void of the following morning. Results: Urine specific gravity values the following morning were not different between the whey trial (1.020 ± 0.004) and the milk trial (1.021 ± 0.005) (p=0.684). Total urine output was also not different between the whey trial (1498.0 ± 245.6mL) and the milk trial (1325.5 ± 426.4mL) (p=0.150). At the end of the study, compared to baseline, net fluid balance was negative for the whey trial (-733 ± 223mL) (p<0.001), and between the two drink trials, final net fluid balance was not different (p=0.088). Conclusion: The main finding of this study is that a whey protein beverage is no better or worse at rehydrating than a trim milk beverage. Uniquely, the present study shows that athletes who exercise in the evening and follow the current rehydration recommendations of consuming 1.5L for every 1kg body mass lost during exercise, were likely to wake up the next day in a hypohydrated state. This would mean that more fluid would need to be ingested before beginning another bout of exercise. Previously such an overnight protocol has not been utilised in rehydration studies.

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  • The Māori Kai semi-quantitative food frequency questionnaire: relative validity and reliability for assessing usual sugar intakes in New Zealand East Coast Māori

    Furter, Elain (2014)

    Masters thesis
    University of Otago

    Background: The rising prevalence of non-communicable diseases (NCDs) such as obesity, diabetes, cardiovascular disease and gout is contributing to global socioeconomic burden. In order to address this issue, the risk factors associated with NCDs need to be identified. Free dietary sugars, and in particular fructose, have been linked to unfavourable metabolic changes associated with these diseases. As New Zealand (NZ) Māori have higher rates of NCDs versus non-Māori, it is of interest to investigate the extent to which dietary sugars intakes might be an explanatory factor. To determine whether sugars intakes influence NCD risk amongst Māori there is a need to develop a culturally-appropriate dietary assessment tool for assessing sugars intakes that is both valid and reliable. Objective: To assess the relative validity and reliability of a culturally appropriate, semi-quantitative food frequency questionnaire (FFQ) intended to measure usual intakes of fructose, glucose, sucrose and total sugars in a Māori adult population. Design: A 33-item FFQ, designed and pretested in Māori adults residing in Gisborne, NZ was used to determine usual sugar intakes over a one month period. FFQ items comprised of important sugary food and drink sources consumed in the target population. The FFQ was validated by comparison with dietary intake data collected through repeat-24 hour recalls (n=3) and reliability measured through re-administration of the tool at a one month interval. 72 Māori adults (24 men and 48 women) provided three 24-hour diet records and completed two administrations of the FFQ and were included in the analyses. Reliability of the FFQ was assessed by cross-classification agreement with weighted Kappa scores, and Spearman correlation coefficients. Mean sugars intakes were evaluated as group means using paired-t tests, and the strength of agreement between the two dietary assessment methods was assessed by the Bland-Altman method. Reliability of the FFQ was assessed by intraclass correlation coefficients. Results: 95% to 97% of participants were classified in the same or adjacent quartiles for all sugars intakes with weighted Kappa scores indicating excellent ability for the FFQ to rank individuals. Cross-classification agreement was even stronger for sugars intakes from non-alcoholic beverages. Mean sugars intakes corresponded well between the FFQ and repeat-24 hour recalls for fructose, glucose and total sugars, but sucrose was significantly different (P0.75). Conclusion: Overall, the Māori Kai FFQ provided repeatable measurements of sugars intakes with good validity, and was able to correctly rank individuals by intake quartiles. Advantages of our FFQ lie in its relatively low response burden, ease of administration, cost effectiveness and cultural appropriateness for use on Māori in epidemiological research. Prospective validation of the FFQ with anthropometric and biochemical markers will provide a means for exploring the diet-disease relationship of sugar.

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  • Relationship between fructose and lactose intakes and irritable bowel syndrome symptoms in a sample of 50-year old Cantabrians.

    Spencer, Robin Lee (2014)

    Masters thesis
    University of Otago

    Background: One therapeutic strategy to alleviate irritable bowel syndrome [IBS] symptoms may be to reduce the intake of dietary fructose and lactose. The majority of patients with IBS believe that diet contributes to their symptoms. They may limit their intake of certain food groups or specific foods that are vital in the diet to provide essential nutrients in attempt to self-manage their symptoms. The purpose of this pilot study was to examine the relationship between fructose and lactose consumption and IBS symptoms in 50-year old adults residing in Canterbury. Methods: The Canterbury Health Ageing and Life Course [CHALICE] study is a longitudinal study consisting of 50-year old (n = 300) Cantabrians. Participants attended a 4 – 6 hour assessment and underwent multiple interviews and procedures. Data used in this thesis include the Birmingham IBS symptom questionnaire and a four-day estimated food and beverage diary [FBD]. Participants who reported any IBS symptoms were categorised into the IBS symptom group and those who reported no symptoms were categorised into the no symptoms group. Using the Birmingham IBS symptom questionnaire, individual participant scores for constipation, diarrhoea, pain score, and total symptom score were calculated. FBD data were converted to nutrients using the food and nutrient analysis programme; Kai-culator. Results: Two hundred and twenty seven (75.7%) participants completed the Birmingham IBS symptom questionnaire and a four-day estimated FBD and were included in the analyses. The IBS dimensions constipation, diarrhoea, and total IBS score were not associated with fructose or lactose intake. A lower prevalence of IBS pain symptoms was associated with higher mean daily intakes of fructose (P = 0.055) and lactose (P = 0.041). Conclusions: The findings suggest that participants with IBS symptoms may have reduced their intake of fructose and lactose. People with IBS could benefit from guidance from a Dietitian to achieve a well balanced diet while excluding foods they have identified that contribute to their particular IBS symptoms.

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  • Reintegrating with Hostile Minds? An Examination of the Role of Social Psychology in Ex-Combatant Management in Rwanda and Burundi

    Ohs, Daniel (2014)

    Masters thesis
    University of Otago

    How can ex-combatants, so normalised to violence, be successfully reintegrated into civilian life? Previous research on ex-combatant reintegration has focused on issues of economics, physical security, political involvement, and narrow community networking, leaving social issues underexplored. Indeed, no study has previously looked at the social psychological aspects of ex-combatant reintegration. In order to explore the presence of social psychological issues within ex-combatant management, a theoretical framework was developed in this thesis covering issues of intergroup division, authoritarianism, discrimination, and negative intergroup contact. Using programme documents and existing academic data, the framework was applied to two case studies of post-conflict ex-combatant management – in Rwanda and Burundi – analysing to what extent these social psychological issues have been addressed in ex-combatant reintegration. In each case study, the two main ex-combatant groups were analysed, and all major official reintegration initiatives were examined. The findings of the comparative analysis are disconcerting. Despite the presence of all social psychological issues from the framework in ex-combatant communities, the recognition of these issues within ex-combatant oriented programmes has been poor. In Burundi, the main reintegration programme has addressed social psychological issues in an inadvertent and fleeting manner, if addressed at all. The majority of the Rwandan programme has taken a similarly indifferent approach. However, a major point of difference is found in the ingando sub-programme in Rwanda which actively adopts social psychological principles for political motivations at the expense of ex-combatant reintegration, exacerbating negative intergroup issues. As such, the study finds a trend in these two contemporary ex-combatant management contexts in which social psychological issues are either not addressed, or misused to negatively impact on intergroup reconciliation. Consequently, the study highlights the importance of including a social psychological perspective in ex-combatant reintegration and peacebuilding initiatives in order to achieve sustainable peace.

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  • A pragmatic tutorial dialogue system: design, implementation and evaluation in a health sciences domain

    McDonald, Jennifer Anne (2014)

    Doctoral thesis
    University of Otago

    In large undergraduate classes, it is time-consuming, costly and seldom practical for the teacher to provide individualised feedback to students on their written responses to questions. A request for advice in relation to these issues, from the coordinator of a large first-year health sciences course at the University of Otago, motivated the research described in this thesis. An intelligent tutoring system (ITS) engages students in a dialogue; students enter their contributions to the dialogue as free text and the system gives a response. Such systems, which employ natural language as their interface, are called dialogue-based ITS or tutorial dialogue systems; they offer some promise for supporting and enhancing student understanding of key concepts through the provision of individualised feedback. The appeal of tutorial dialogue is that questions are embedded in a tutorial plan: the questions arise in a meaningful context and concepts and ideas are linked together in a coherent form. This allows each student contribution to be individually assessed. However, ITS are not currently in widespread use in higher education settings and there has been considerable controversy around their application in this context. Practical issues relating to the time and cost for development, the difficulty of adapting to specific teaching contexts, and pedagogical objections which relate to the idea of student modelling are among some of the barriers to their widespread adoption. In this thesis, a rationale is presented for revisiting tutorial dialogue systems in the context of large-class teaching. Two broad goals for this research are delineated. The first goal was to design, build and evaluate a new tutorial dialogue system for the cardiovascular section of a first-year undergraduate health-sciences paper. The new system is firmly empirically-based, with both the teaching context and real student responses to questions integral to its design and implementation. The second goal was to determine whether a tutorial dialogue system, which provides students with the opportunity to practise writing answers to short-answer questions and gives automated feedback about these answers, would result in improved student performance. In order to explore the second goal, two versions of the new system were developed. The first version of the system required students to type their response to questions as free-text; in the second version, students selected the answer they preferred from a menu of options. Student volunteers were divided into three groups: a control group, a free text tutorial group and a menu-based tutorial group. The performance between the two tutorial groups and the control group were compared to test whether free-text entry conferred any performance advantage over selection from a menu of options. The design and implementation of the new tutorial dialogue system is described in detail and some limitations are discussed. The evaluation of the new dialogue system with 578 student volunteers in a real-class setting is described. Student perceptions of the system were broadly positive and there was strong uptake of the system compared with an earlier prototype. The experiment, which was set up specifically to test the performance of the system overall, as well as to establish if there are differences between free-text and menu-based versions, found student performance gains did occur among students who used either version of the new tutorial dialogue system but no differences were found between the two versions. The main conclusion to be drawn from this research is that the new system can be deployed in a large-class setting and, at least in the context of first-year health sciences undergraduate courses, is likely to find acceptance with students, in addition to having a positive impact on their performance. The development of a stable platform for the further study of tutorial dialogues and the automated creation of a large corpus of tutorial dialogues are spin-off benefits from the research. Finally, this research is a small contribution towards getting contemporary tutorial dialogue systems back on the educational agenda.

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  • The Impact of Fatherlessness on the Way One Relates to God as Father

    Dobbs, Peter John Eric (2014)

    Masters thesis
    University of Otago

    Largely as a result of the breakdown of nuclear families in Western society, rates of fatherlessness are increasing. The purpose of this research is to investigate what impact growing up with an absent or dysfunctional father has on faith development and the perception of God. Although there is a large body of scholarly material which addresses the influence of one’s father on the perception of God, there is no consensus as to how this influence is exhibited. Nor has there been any significant inquiry into the impact of fatherlessness on faith development specifically. Researchers have tended to ground their investigations in the contradictory views of either Attachment Theory or Projection Theory and then find support within their research for whichever developmental perspective they sought to prove. Attachment Theory suggests that in reaction to an absent father a child may exhibit a compensation response, perceiving God to be a perfect father figure and an attachment substitute. Conversely, Projection Theory posits that a negative perception of father will result in the child demonstrating a correspondence response and transmitting these negative feelings onto their view of God. This research investigates the impact of fatherlessness on the image of God as Father and seeks to demonstrate the existence of both compensation and correspondence responses within a fatherless population. Quantitative surveys were collected from 505 respondents in seven separate church congregations of various denominations in the greater Waikato region. Additional qualitative information was collected from an open ended question on the survey form and by interviewing three survey participants as representatives of key population groups. By analysing the participants’ perceptions of their father and their comparable perceptions of God, I was able to identify similarities and differences in their answers and distinguish correspondence and compensation responses. Although I found strong support for Attachment Theory in the fatherless population, with 49.4% of those who were fatherless demonstrating a compensation response, the most significant influencing factor on the perception of God was a negative perception of father. Respondents with a negative perception of father, whether fatherless or not, had a higher rate of compensation responses (61.1%) and viewed God as more distant and less nurturing, involved, or accepting than did participants with a positive view of father. Despite the strong evidence of attachment substitution amongst those with a negative perception of father, lower overall scores for attributes of God and larger standard deviations in those scores suggested that some who were affected by an absent or dysfunctional father exhibited a correspondence response. This was further reinforced by the interviews and the comments written on the survey forms, which suggest that although some of those affected by fatherlessness may naturally demonstrate a compensation or correspondence response, others’ responses may change over time. It appears that some may begin by transferring a negative perception of father onto their image of God, but as their faith develops, evolves, and matures, they may come to view God as the perfect Father they had lacked. The thesis concludes with a discussion of some of the implications of this research for congregational ministry.

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