5,886 results for University of Otago

  • Advances in conservation of Māori textiles; analysis and identification

    Smith, Catherine Ann; Lowe, Bronwyn J.; Paterson, Rachel A. (2016)

    Conference paper
    University of Otago

    A number of new methods and technologies for investigating Māori textiles have emerged from ten years of research in the Department of Applied Sciences - Clothing and Textile Sciences, University of Otago, Dunedin, New Zealand. Research projects undertaken include development of numerous identification methods for textile plants endemic to New Zealand (bright field microscopy, Scanning Electron Microscopy (SEM), Micro-Computed tomography (micro-CT), Polarised Light Microscopy (PLM)); exploration and improvement of safe display parameters for naturally-dyed Māori textiles (artificial light-ageing, microfading); and testing the efficacy of consolidants recommended for remedial conservation treatment of black-dyed muka (fibre) from harakeke (New Zealand flax, Phormium tenax). Of note is the collaborative and interdisciplinary nature of the work undertaken (research partnerships with iwi (Māori tribal grouping), customary weaving practitioners, New Zealand museums, conservation laboratories and other University departments), in addition to the adaptation of international standard textile testing methods to better reflect the artefact types of interest (for instance testing of fibre aggregates rather than woven European fabrics). Research outcomes are of relevance to practitioners and artists as well as those caring for Māori taonga, and have added to knowledge about both Māori textiles, and plants and dyes used in Māori textiles production.

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  • Pneumatology and Union: John Calvin and the Pentecostals

    Ross, Peter Graham (2017)

    Doctoral thesis
    University of Otago

    The aim of this research is to identify whether affinities, or touch points, exist between John Calvin’s pneumatology and account of the union between the believer and Christ and Pentecostal thought on these issues. If it can be demonstrated that they do, then Calvin could be of great assistance to Pentecostals as they seek a global theology. John Calvin’s thought on the subjects is summarised, and a review undertaken of Pentecostal thought which focuses on Spirit release (the preferred term for what is most commonly termed Spirit baptism among Pentecostals), and the work of the Spirit in salvation. The narrowness of this review is necessary as a global Pentecostal theology which can be summarised in the same way as Calvin’s thought does not yet exist. With the respective positions established, conversations between them are constructed within three subjects: The Assurance of Faith; Providence and Guidance; and Justification. These subjects are chosen because of the heavy involvement of the Spirit within each in both systems, and the contribution made by the union as the arena of the Spirit’s work in each. Within each of these doctrines a number of touch points are identified, where there is either agreement between the systems or there is some common ground. The latter might be a similarity of process, or a matter of degree. For example, Macchia posits a direct role for the Spirit in justification, whereas for Calvin justification is entirely Christological. However, the work of the Spirit in establishing the prior union between the believer and Christ is necessary for justification in Calvin. This constitutes a touch point or affinity which rests on some common ground, not on direct agreement. In the final chapter, there is extended consideration of Spirit release. This firstly establishes the term as a valid description of the encounter to which Pentecostals testify at the core of their witness. Secondly, it shows that a concept can be developed which enables Spirit release to sit well as an extension from Calvin’s thought. With this linkage established, it is shown that the touch points identified under the above headings are so substantial that Pentecostals can usefully look to Calvin on pneumatology and union as ground on which they can develop their own views in order to deepen their own theology and so move towards a global Pentecostal theology.

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  • A feasibility study to introduce regular activity breaks in the workplace: monitoring the effect of regular activity breaks on occupational musculoskeletal discomfort, fatigue, and productivity

    Carter, Hannah (2017)

    Masters thesis
    University of Otago

    Background: Regularly interrupting sedentary behaviour with light physical activity has been shown to reduce postprandial glycaemia. However, these effects have been examined in response to a single day of light activity bouts in a controlled lab setting. The effects of long- term change in sitting behaviour, over weeks or months, on postprandial glucose and insulin metabolism in a free-living setting have not been examined. Testing this would require a trial in which participants achieve a sustained increase in light activity bouts over weeks to months in their workplace. However, interventions investigating the practicality and effects of taking regular activity breaks to reduce sedentary time are scarce. Objective: To conduct a feasibility trial to test the effectiveness of methods to increase regular activity breaks in a sedentary workplace. In addition, to investigate the impact of increasing activity breaks during the workday on musculoskeletal discomfort, fatigue, and productivity. Methods: Twelve University of Otago employees were encouraged to perform light activity breaks (at least 2 min in duration) every 30 min of their 8 h workday, throughout a five-week intervention period. Break reminder applications (apps) and social media (Instagram) were used to encourage participants to take the breaks. Modified versions of the Nordic, Individual Strength, and Health and Work Questionnaires were self administered to assess workplace musculoskeletal discomfort, fatigue, and productivity respectively, at the end of baseline, weeks 1, 3, and 5. Feasibility Questionnaires were verbally administered at baseline, weeks 3 and 5, to explore participant’s attitudes around taking regular activity breaks. Results: The mean number of activity breaks per workday significantly increased from 12.4 at baseline to 15.8 at the end of the intervention (p<0.001). The total number of musculoskeletal discomfort reports over the past five workdays decreased from 27 at baseline, to 21 at the end of week 5. Total fatigue significantly decreased by 9.6 points (p=0.010). Significantly lower scores were observed in two of the subscales of fatigue, depicting decreased subjective fatigue (p-0.010) and increased levels of physical activity (p=0.040) from baseline to week 5. Although no significant differences in total productivity were observed, mean scores showed significant improvements in the subscales; impatience and irritability (p=0.049), work satisfaction (p=0.038), and personal life satisfaction (p=0.008). Feasibility Questionnaire transcripts showed that using break reminder apps and having the support of colleagues was helpful in facilitating regular activity breaks. Barriers to taking regular breaks included: work commitments, feeling less productive, and others perceiving them to be less productive getting up to take activity breaks every 30 min. However, the majority of participants planned to continue the activity breaks following the interventions completion. Conclusion: These findings suggest positive trends in reducing musculoskeletal discomfort, fatigue, and increasing productivity following the introduction of regular activity breaks into the workplace. Therefore these are unlikely to be barriers to taking regular activity breaks in an occupational setting. Modified versions of the Nordic, Individual Strength, and Health and Work Questionnaires trialled in this study are considered to be suitable in assessing workplace musculoskeletal discomfort, fatigue, and productivity in a large-scale study.

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  • Zinc status of athletes compared to non-athletes

    Holdaway, Cushla Rose (2017)

    Masters thesis
    University of Otago

    Background: Zinc is an essential micronutrient to human physiology, and has many vital roles in physical exertion. It is understood that athletes have increased dietary requirements to support their physical training. However, there is a lack of evidence focusing on zinc status in athletes to establish whether zinc deficiency is a common issue of concern. Aims: The aim of this research project is to undertake a systematic review of the zinc status of athletes (aerobic, anaerobic, or a combination) compared to healthy non-athletes aged 18 to 65 years. The studies must be cross-sectional and assess at least one zinc biomarker. Design: Keywords and phrases were entered into PubMed, Scopus, SPORTDiscus, and the Cochrane Library. After removal of duplicates, all citation title and abstracts were screened for eligibility. The final data from the included literature was extracted and interpreted. Results: Sixteen studies were eligible for inclusion. Fifteen out of nineteen athletic groups had lower plasma zinc concentrations compared to non-athletes. Twelve out of 15 athletic groups had higher dietary zinc intakes compared to non-athletes. There was no obvious relationship between dietary zinc intake and plasma zinc concentration in athletes, but this does not exclude other factors affecting athletes zinc status compared to non-athletes. Conclusion: Plasma zinc concentration appears to be independent of dietary zinc intake in athletes, however, losses in sweat and urinary excretion may impact the zinc status of athletes. This review does not explain the implications zinc deficiency may have on athletic performance, nor does it describe how a zinc deficiency may exist in the absence of signs and symptoms. The main barrier to this lack of evidence is the absence of a single, robust zinc biomarker with internationally defined reference ranges.

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  • Application of pulsed electric field processing for production of low sulphite wine and the selective inactivation of non-Saccharomyces yeasts

    Vidya, Kethireddy (2017)

    Doctoral thesis
    University of Otago

    Winemakers add sulphites during winemaking for their antimicrobial (control of indigenous and undesirable microbes) and antioxidant properties. However, the demand for no added sulphite (NAS) or reduced sulphite wines, coupled with a demand for wines with lower alcohol and a distinctive regional character is increasing interest in making wines with indigenous wine yeasts through mixed or spontaneous fermentations. Pulsed electric field (PEF) processing of grape must has previously been proven to enhance extraction of juice, polyphenols/bioactives and to reduce the microbial levels by either reversible or irreversible electroporation of cell walls. To determine the suitability of using PEF in wine making and to reduce the reliance on the use of sulphites, this study investigated the impact of PEF at levels suitable for extraction and/or sulphites on Saccharomyces and non-Saccharomyces yeasts during the cold soak conditions. The estimation of sub-lethal injury in S. cerevisiae using the traditional approach incorporating a maximum non-inhibitory concentration (MNIC) of sodium chloride (NaCl) was also tested and its accuracy was evaluated in light of the interactions between the initial processing stress and the subsequent selection stress. In addition, studies with PEF, sulphites and the combination of PEF (1.0-1.1 kV/cm and 18-260 kJ/kg) and sulphites (35-350ppm) at 4 and 7 Log CFU/mL at exponential and stationary growth phases in S. cerevisiae, P. kluyveri and H. uvarum were conducted during cold soak conditions for 8 days. Further biochemical analysis using oxidative damage (protein carbonyls and lipid peroxides) and antioxidant enzyme (SOD, CAT, GPx, GR) activity biomarkers was conducted following PEF (1.0 kv/cm,196 kJ/kg), the addition of sulphites (350 ppm) or PEF pre-treatment followed by sulphites in S. cerevisiae, P. kluyveri and H. uvarum over a period of 48h at cold soak conditions. The results confirm the versatility of PEF for the extraction of grape polyphenols while simultaneously managing the total yeast numbers during maceration, facilitating either mixed/ spontaneous fermentation or the introduction of commercial Saccharomyces spp. The evaluation of MNIC method for quantifying sub-lethal injury showed the shortcomings of the method and the need to delve further into the biochemical and molecular approaches to understand the impact of sub-lethal injury. Screening the impact of a range of PEF and sulphite levels at different initial concentrations and growth phases of the three yeast spp and the biochemical analysis monitoring oxidative stress markers following PEF, sulphites and PEF pre-treatment followed by sulphites showed that there was differential response among the yeast spp. In addition, the pre-treatment of PEF was proven to enhance the impact of sulphites and a differential response in S. cerevisiae, P. kluyveri and H. uvarum. This effect is suggested to be due to PEF (1.0-1.5 kV/cm) inducing reversible electroporation which facilitates the entry of sulphites into the cell. Growth phase, growth temperature and media pH were all found to be key parameters in the selective inactivation process. In conclusion, it is suggested that use of PEF during maceration at cold soak conditions is a feasible technology for the production of reduced sulphite wines.

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  • The Scope of the Validation Power in the Wills Act 2007

    Peart, Nicola; Kelly, Greg (2013)

    Journal article
    University of Otago

    When the new Wills Act was adopted in 2007 it made a number of changes to the law regulating wills. Probably the most radical change is the power in s 14 to validate wills that do not comply with the formal requirements for making a valid will in s 11. This change follows Australia’s lead, where a similar power, referred to as a dispensing power, has existed since 1975. Initial concerns that it would encourage sloppy will-making and result in uncertainty and a flood of applications turned out to be groundless. The constraints imposed by the wording of the Australian provisions together with judicial restraint in the exercise of the power, at least initially, as well as the increased cost, delays and uncertainty about the outcome of applications were strong incentives for complying with the formal requirements. The Australian experience and the benefits of saving wills from invalidity on purely technical grounds persuaded the New Zealand Law Commission to recommend the adoption of a similar, though not identical, power in its Report Succession Law — A Succession (Wills) Act in 1997. That recommendation was eventually implemented with the adoption of the Wills Act 2007. The Wills Act 2007 came into force on 1 November 2007. It applies to all persons dying on or after that date, regardless of the date of the will. It was not until August 2009, however, that the validation power was invoked for the first time. The reason for the delay may have been because the validation power could not then be applied to wills made before 1 November 2007 even though the will-maker died after that date. The transitional provisions prevented retrospective application of the validation power. An amendment in 2012 now enables the power to be used in respect of all non-compliant wills regardless of the date they were made. Since the first application to validate a non-compliant will in 2009 there has been a steady increase in the number of applications. By October 2012 at least 43 applications had been made, of which 41 were successful. The two applications that were declined failed because there was no jurisdiction at the time to validate wills made before 1 November 2007. In the 41 cases where jurisdiction did exist, the success rate was 100 per cent. From this body of case law a picture is beginning to emerge of a jurisdiction that has the potential to go well beyond its Australian counterpart in giving effect to testamentary intentions. The aim of this article is to evaluate the use of the validation power in New Zealand to determine its scope and assess the risks associated with a broad jurisdiction. Before embarking upon that task, it is necessary to outline the formal requirements for a valid will and explain their purpose.

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  • Reproduction and larval ecology of the toheroa, Paphies ventricosa, from Oreti Beach, Southland, New Zealand

    Gadomski, Kendall Lynn (2017)

    Doctoral thesis
    University of Otago

    Paphies ventricosa is a large surf clam endemic to New Zealand with a patchy distribution and whose populations have substantially declined during the past century owing to overfishing and habitat degradation. Poor recruitment is now evident, and therefore, understanding the larval recruitment of P. ventricosa is key to developing and implementing conservation strategies for the species. In order to identify factors driving larval recruitment in toheroa, Paphies ventricosa, from Oreti Beach, Southland, New Zealand, the southernmost known extent of the species, various studies were carried out from 2011 to 2014 in the field and the laboratory In 2011, the reproductive cycle of P. ventricosa was examined over one year in a population at Oreti Beach. In 2012, the spatial variation in reproduction among four sites along Oreti Beach, including the site from 2011, was quantified from body indices and the histological examination of gonads. Based on changes in oocyte size, gametogenic stage and condition index, we observed a species with a primary spawning in spring and a second spawning event in late summer/autumn, with no resting phase but minimal reproductive activity over winter. Seasonal reproduction corresponded with warmer sea surface temperature and a peak in chlorophyll-a concentrations in the region. Small-scale (< 15 km) variation in the timing of spawning was also evident along Oreti Beach, with a degree of asynchrony that could affect fertilisation success in the population. These patterns may be an important consideration when identifying areas that may be considered for conserving source populations. Using scanning electron microscopy and light microscopy, fertilisation, and embryonic and larval development were observed at three culturing temperatures (12, 16 and 20 ºC). The progress of development follows that previously described for the family Mesodesmatidae, with P. ventricosa having a small egg (63–70 mm), with an 83–102 mm trochophore stage observed at 15 h, and a 100 mm D-veliger larva observed at 22 h at 12 and 16 ºC, and 37 h at 20 ºC. At 20 ºC, the pediveliger larval stage was reached by 31 d. While the morphology of the embryonic and larval stages of P. ventricosa is typical for bivalves, we show that in this species the shell field invagination occurs in the gastrula stage and that the expansion of the dorsal shell field occurs during gastrulation, with the early trochophore having a well-developed shell field that has a clearly defined axial line between the two shell lobes. The growth of P. ventricosa larvae cultured at 12, 16 or 20 ºC over 39, 33 and 31 d respectively, was faster at warmer temperatures. Using the temperature quotient Q10 at day 27 to quantify the response to temperature, values of Q10 = 1.82 for the range 12–16 ºC and Q10 = 2.33 for the range 16–20 ºC were calculated. Larval shape was not temperature dependent, suggesting that the smaller larvae found at colder temperatures reflect a slowing of larval development, rather than physiological damage by temperature resulting in abnormal larval development. Temperature is one of the most important environmental factors controlling development in marine invertebrates, and thus likely plays a critical in recruitment dynamics. The temperature thermal tolerance of fertilisation and early larval development in Paphies ventricosa was examined to understand the role of temperature in early larval recruitment success. Fertilisation was examined across a thermal gradient of 10.5 to 30 ºC in an aluminium heat block. Fertilisation was considered successful by microscopic observance of the breakdown of the germinal vesicle, and the appearance of the fertilisation envelope and polar body. The thermal tolerance of development was examined across a thermal gradient of 8.0 to 25.5 ºC in an aluminium heat block at 2, 15, 22, and 37 h post-fertilisation. Fixed samples were examined using light microscopy and classified into the developmental stages of unfertilised, fertilised, embryonic (2-64 cell embryos), blastula, trochophore, veliger, and abnormal. There was a significant effect of temperature on the fertilisation success which ranged from 4.6% to 46.7%. Fertilisation was > 30% successful between 16.0 and 21.0 ºC, and was successful beyond the natural temperature range of the species. P. ventricosa larva were tolerant to temperatures beyond the naturally occurring temperatures during spawning/development periods, but were most successful around 15 ºC. While temperature is important in the recruitment of marine invertebrate larvae, feed availability is also crucial, and often thought to be more important in overall larval development. The combined effects of temperature (12, 16, and 20 ºC) and feed concentration (1:1 mixed algal diet of Tetraselmis chui and Isochrysis galbana; 1,000, 10,000, and 20,000 cells ml-1) were examined in P. ventricosa larvae over 17 days. There was found to be significant combine effect of sampling day, temperature, and feed concentration on larval shell length. By 17-d post-fertilisation, the combined effect of feed concentration on larvae in each temperature became more apparent. Unlike the results of Chapter 3 when larvae were fed a single species (T. chui) diet at 10,000 cells ml-1, larvae reared at the colder temperatures had the largest shell lengths by 17-d post-fertilisation. At 17-d fertilisation, larvae at 12 ºC grew best when fed 20,000 cells ml-1, and 16 and 20 ºC grew best at 10,000 and 1,000 cells ml-1, respectively. Overall, the results of this research fill in many gaps in our knowledge about the life history of Paphies ventricosa. In particular, the reproduction of the local Oreti Beach population and the early larval ecology, with implications for both the northern and southern populations, have been explored in depth. This is the first study of its kind for many of its components, including the detailed microscopic (both scanning electron and light microscopy) examination and description of the early larval stages of toheroa, and the identification of the fertilisation and thermal development windows in the species. In addition, it is the first study in toheroa to examine the combined effects of temperature and feed concentration. The present study has greater implications in regards to other bivalves of similar distributions and habitats, and provides insight into the conservation and management of the species.

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  • Kelp-forest response to light limitation

    Desmond, Matthew (2017)

    Doctoral thesis
    University of Otago

    The loss of canopy-forming macroalgae is one aspect of coastal ecosystem degradation that is being driven by anthropogenic stressors. The drivers of canopy loss are, in many cases, well understood, but the effect of light availability is a factor that has been relatively overlooked given its importance. Light availability controls marine productivity and is a fundamental factor that shapes the structure of kelp-forest communities. When the variability of light availability exceeds natural thresholds as a result of anthropogenic stress, macroalgae struggle to acclimate or adapt and community structure and productivity is altered. Significant modification of the coastal light environment has likely occurred in many of the world’s coastal seas, and further increases in turbidity are predicted as a result of land use intensification, sea level rise and changing climatic conditions. This prediction forms the premise for this body of work. The primary objective was to detail the effect of light availability on the structure and function of kelp-forest communities, and to quantify the physiological processes that underpin this relationship. From this, a better understanding of how kelp-forest communities will respond to future changes in light availability is possible, and more accurate predictions of kelp-forest productivity can be made. Subtidal light availability was significantly less on reefs adjacent to coastlines dominated by urban, agricultural and forestry land use when compared to similar reefs associated with coastlines of native forest. When averaged over a seasonal cycle, light availability at 10 m on the low-light reefs was approximately half that measured on high-light reefs. The kelp-forest communities inhabiting these reefs were also shown to differ significantly. Although similar macroalgal species were shared between regions, community biomass was two to five times greater on high-light reefs. This was primarily due to a greater contribution by large canopy forming macroalgae. Additionally, macroalgae typically had a larger and deeper depth distribution on high-light reefs, in effect, providing more habitat and food to the kelp-forest ecosystem. This resulted in 0.7 – 2.8 times more epifaunal biomass being supported per square metre in high- compared to low-light reefs. Although this difference was largely due to greater habitat availability on high-light reefs, habitat quality was also shown to influence epifaunal biomass. The invasive kelp, Undaria pinnatifida, contributed significantly to community biomass on low-light reefs but was shown to support low epifaunal biomass as it offers low refuge value and, being an annual species, is an unstable host. Light limitation and the way that light is delivered to kelp-forest communities was shown to significantly influence the physiological processes of photoacclimation and photosynthesis. A photoacclimation response to light limitation was observed at the individual and kelp-forest community level between the low- and high-light reefs. In both cases greater pigment concentrations and accessory pigment to chlorophyll a ratios were recorded within the low-light setting. The cost of acclimation under low-light conditions helps to explain the disparity in standing biomass between the low- and high-light reefs, as energy, otherwise used for growth, is diverted to synthesise additional photosynthetic pigments. There was also evidence that a number of species on the low-light reef were living at the edge of their photosynthetic ability, and that a further reduction in light would likely result in a loss of those species at deeper depths. The rate that light is delivered to kelp-forest communities was shown to significantly affect macroalgal productivity, and in some cases may be more influential than the total amount of light that they receive. Greater photosynthetic efficiency at lower light intensity was shown to compensate for even large disparities in the total amount of light that dominant kelp-forest species received. This demonstrates that both the limitation of light and variability of its delivery are key determinants of kelp-forest structure and productivity. This thesis provides evidence that is suggestive of a change in kelp-forest communities in southern New Zealand as a result of light limitation. The findings from this study are applicable at a global scale and provide important information that will help improve estimates of kelp-forest productivity and persistence, now, and under future light regimes.

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  • EAT5: Eating frequency in 5-year old New Zealand children

    Kennedy, Lucy Jennifer (2017)

    Masters thesis
    University of Otago

    Background: Childhood obesity is a growing epidemic in New Zealand, with 11% of children obese and 22% overweight in 2014/15. There is evidence that eating more frequently may be associated with improved body composition, however the current literature is limited. Eating frequency may also be associated with nutrient intake or diet quality. Eating frequency is important given that children have a smaller stomach capacity, yet high nutrient requirements, compared to adults. Objective: The aim of this study was to investigate eating frequency in 5-year old New Zealand children, and whether eating frequency is associated with body mass index (BMI), energy or nutrient intake. Design: The EAT5 Eating Frequency cross-sectional study recruited primary caregivers of healthy 5-year old children based in Wellington, Auckland and Dunedin, New Zealand (the candidate was responsible for the Wellington phase of the study). Each participant completed a weighed diet record (WDR) of their child’s food and beverage intake on three non-consecutive days over three to four weeks. The height and weight of each child were measured at baseline, and a food frequency questionnaire (FFQ) was completed at each of two appointments. Eating frequency was determined using parent-defined eating occasions, excluding occasions consisting of water only. Dietary data were entered using the dietary analysis software programme, Kai-culator, and average nutrient intake was analysed. Results: Fourteen children were recruited in Wellington, resulting in a final sample size of 82. The average eating frequency was 6.1 eating occasions per day. Mean BMI z-score in this sample was 0.37 (standard deviation 0.72). There was no significant association between eating frequency and BMI (odds ratio 0.90; 95% CI 0.67, 1.21; p = 0.478). When children ate at least 6 times per day, they consumed significantly more energy (942 kilojoules; 95% CI 496, 1387; p < 0.001) than when they ate five or fewer times a day. While total intake of carbohydrate, protein, fibre, sugars and added sugars were significantly higher with higher eating frequency, there was no significant difference in percentage of total energy intake from carbohydrate, protein or fat. However, significant positive associations were observed between eating frequency and calcium and iron intake. There was no significant association found between eating frequency and vitamin C or zinc intake in this sample of 5-year old children. Conclusion: On average, eating frequency in this study was consistent with the Ministry of Health guideline that up to 6 meals or snacks should be eaten a day, although average eating frequency exceeded this recommendation for 41% of children. Eating frequency was not associated with the BMI of 5-year old New Zealand children in this study. Furthermore, eating frequency did not appear to be associated with the percentage of energy from macronutrients. However, there may be benefits for calcium and iron intake with higher eating frequency associated with higher intake.

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  • Estimating Free Sugars Intake in New Zealand

    Kibblewhite, Rachael Louise (2017)

    Masters thesis
    University of Otago

    Background: Sugar has been implicated as a cause or risk factor in a number of diseases. Recently the focus of research and recommendations have shifted to emphasise the potential importance of free or added sugars on health. In response to the literature which suggests a negative association between free sugars and health (particularly relating to dental caries) the World Health Organisation (WHO) updated their recommendations for intake of free sugars. Monitoring the extent to which populations are achieving these recommendations is difficult, primarily because free sugars are indistinguishable analytically from sugars inherent to a food. Thus, in the New Zealand (NZ) food composition database there is currently no nutrient information for free sugars and as a result, estimates have not been possible for free sugar intakes in NZ. Objective: The first objective of this research project was to update the current New Zealand Food composition database (NZFCD) to include estimates of free sugars for every food. The second objective was to estimate intakes of free sugars in NZ adults using data from the New Zealand Adult Nutrition Survey 2008/09 (NZANS 08/09), with the intention of comparing these intakes with international recommendations for free sugars, such as those set by WHO. Methods: Estimates of free sugars were created for each food record in the NZFCD, using a 10-step protocol. Intakes of free sugars in the NZANS 08/09 were estimated by matching free sugar estimates for each food item to the 24-hour recall data. Survey weighted estimates of free sugars intakes were calculated by age group, sex, and ethnicity. Usual intakes were estimated by adjusting for intra-individual variation using the Multiple Source Method (MSM). Population intakes were compared with the WHO recommendations for free sugars. Results: Free sugars content (g/100g) of 2779 foods were estimated. Estimates for 2543 were calculated by objective measures and the remaining 236 foods from subjective measures. Estimated median intake of free sugars in NZ adults was 57 g/day (57g, 95%CI: 55, 59) which equated to 11.1% of total energy (TE), this was significantly higher than sucrose (48g, 95%CI: 46, 50) and added sugar (49g, 95%CI: 47, 51). Intakes were highest among younger age groups. Young males (15-18 years) had the highest intake (89g/day), and young females had the highest by %TE. An estimated 57.8% of the total population are estimated to be exceeding the WHO recommendation that free sugars intakes should be <5% TE. Conclusions: This study offered valuable insight into the consumption of free sugars, improving the understanding of who may be at the greatest risk of poor health outcomes. It found that free sugar consumption of specific population groups (such as younger adults) was high in comparison with WHO recommendations, suggesting that public health strategies to reduce free sugars intakes would be strengthened by targeting younger adults. Updating the NZFCD to include free sugars will enable future research to investigate the relationships between consumption of free sugars and health outcomes, in a New Zealand setting.

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  • Characterisation of Novel Nitric Oxide and Carbon Monoxide Donors

    Kumari, Sweta (2014)

    Doctoral thesis
    University of Otago

    Nitrogen monoxide (NO) and carbon monoxide (CO) are small messenger molecules which play multiple roles in mammalian physiology. Currently, available NO and CO donor drugs are limited in therapeutic potential due to a lack of organ or tissue specificity and stability. These limitations have stimulated great interest in the development of compounds that can generate NO and CO in a controlled and sustained manner with minimal toxicity. Two new therapeutic agents are under development at the University of Otago, New Zealand, tDodSNO, a photoactivated NO donor and CO-13, an organic based CO donor. This thesis examines some of their pharmacological characteristics trialing as cardiovascular and anticancer therapeutics. Our data demonstrate that photosensitive tDodSNO had a half life of > 4 h under photoactivation (25 W/m2) and was highly stable in vitro in the absence of photoactivation (0 W/m2). The NO release kinetics of tDodSNO was then compared to other commonly studied SNT’s, GSNO and SNAP. We found a steady state concentration of 8 ± 2 μM NO was achieved under photoactivation (300 W/m2) of 100 μM tDodSNO which could be regulated by modulating intensity of photostimulus. The CO release kinetics of CO-13 was also investigated and we found that CO-13 was a slow releasing CO donor compared to commonly studied metal based CO donor (CORM-2). To test the efficacy as vasorelaxing agent, vasorelaxation on vascular smooth muscle tissue was investigated. There was an 8 fold decrease in EC50 value of tDodSNO upon photoactivation. In contrast, both GSNO and SNAP induced NO dependent vasorelaxation, at lower concentrations than tDodSNO, but this activity may be due to their rapid metabolic decomposition, and could not be modulated by photoactivation. Similar to tDodSNO, CO-13 was found to be a potent vasorelaxing agent compared to CORM-2. We also evaluated the cytotoxicity of tDodSNO and CO-13 on A549 lung cancer cell line. Our data with tDodSNO revealed that the photoactivation (25 W/m2) induced highly significant increases in cytotoxicity compared to nonphotoactivation. A time and concentration dependent decrease in cell viability was observed with CO-13, which was substantially different compared to its CO depleted form BP-13. In conclusion, our study suggests that photosensitive tDodSNO and CO-13 have the potential to be promising novel cardiovascular and anticancer therapeutic agents.

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  • Obedience that Saves: a Dogmatic Inquiry into the Obedience of Jesus Christ in Karl Barth's Doctrine of Reconciliation as shown in his Church Dogmatics

    Fong, Edmund (2017)

    Doctoral thesis
    University of Otago

    This thesis demonstrates the dogmatic significance the motif of the obedience of Jesus Christ has within Karl Barth’s doctrine of reconciliation as shown in the Church Dogmatics. The significance is shown by considering the threefold ‘directional’ manner that Barth treats the obedience of Jesus Christ: i) a ‘backward’ direction in drawing the incarnate obedience of Jesus into the triune Godhead ii) a present orientation in the sense of Jesus’ obedience displayed as it is in the incarnation, and iii) a ‘forward’ direction showing how the obedience of Christ leads to the obedience of those who are reconciled. At the same time, the investigation is conducted by addressing doctrinal or theological issues related to Jesus’ obedience arising from Barth’s treatment of the subject matter, rather than in chronological order as these treatments appear in the Dogmatics. The following two key findings are presented: first, in following the Tradition, Barth affirms the obedience of Jesus Christ as a genuine and authentic human obedience, involving an act of human volition in response to a higher calling or command. This genuine obedience of Jesus Christ comes to play a causative and instrumental role in God’s reconciliatory program with humankind. It is in the second key finding that we locate Barth’s distinctive contribution to the dogmatic significance of Jesus’ obedience vis-à-vis that of the Tradition. That is, Barth equates the incarnate obedience of Jesus Christ with the divine obedience of the eternal Son within the triune Godhead. In this move, Barth goes so far as to tether the command-obedience relationship between the Father and the Son in eternity to the eternally begetting-and-being-begotten relations of origin that characterize the Father and the Son within the divine processions. I argue that Barth is able to assert the notion of divine obedience only because of his underlying framework of actualistic ontology. This, in turn, is a framework specifying God’s eternal election of Jesus Christ as a divine action of self-determination that carries ontological implications for God’s triune being. Given that the second mode of being of the triune God from the outset is identified as Jesus Christ, Barth conceives the incarnate obedience of Jesus Christ as the divine obedience of the eternal Son under the trope of his actualistic ontology. The immediate result of such a conception is that the dogmatic role and function occupied by the obedience of Jesus Christ is extended from its usual domain within the economy of salvation to that of the divine will and purpose, and even to the immanent being of God. The obedience of Jesus Christ could in fact be said to occupy a co-participatory albeit asymmetrically ordered role in the determination of the divine ontology itself that arises from the divine election. Barth gives maximum space to the specification of the role and function of Jesus’ incarnate obedience in a manner unprecedented within the Tradition while preserving the divine initiative and primacy. God allows the incarnate obedience of Jesus Christ to have a part in the divine self-determination that arises from the eternal decision of (self-) election, but it is still God who elects, who so determines his being in just this way, revealing himself as the God who, as Barth states, “does not will to be God without us.” (CD IV/1, p. 7)

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  • Mechanistic Role of the Secondary and Tertiary Coordination Sphere of Cysteine Dioxygenase

    Davies, Casey G. (2017)

    Doctoral thesis
    University of Otago

    The focus of this thesis is an investigation of the rat enzyme cysteine dioxygenase (CDO). CDO is a non-haem mononuclear iron(II) enzyme that incorporates molecular oxygen into cysteine to form cysteine sulfinic acid. CDO has been implicated with a range of neurological disorders as well as many forms of cancer. Chemically, CDO has two fascinating and unique features. Firstly, it has a neutral three-histidine coordination environment; the more common environment found in most related enzymes is the negatively charged two-histidine carboxylate environment. Secondly, a post- translational thioether modification occurs between two secondary coordination sphere residues in the active site, C93 and Y157. Although CDO has been investigated for many years, the mechanism is still not fully elucidated. The aim of this thesis is to develop the current understanding of the mechanism of cysteine dioxygenase by probing both multiple-turnover and single-turnover kinetics. Multiple-turnover investigations of the secondary and tertiary coordination sphere have elucidated the roles of the crosslink, C93, Y157 and H155. The crosslink increases the rate of reaction. Contrary to current belief, the rate is not increased by the presence of the crosslink itself. Instead, the rate is increased by the act of removing the thiolate of C93 from the active site. This was shown by both the theoretically derived 100 % crosslinked enzyme having almost identical pH independent parameters as the C93G variant. However, removal of Y157 with Y157F did show a substantial variation in reactivity. Further investigations showed that Y157 works in tandem with H155 to protect the active site from secondary cysteine attack. Substrate binding studies support this as the Mössbauer spectra showed variations in the five and six-coordinate cysteine bound iron complexes when Y157 was modified and variations in just the six-coordinate complex when H155 was mutated. Single turnover studies utilising stopped-flow spectrophotometry showed that two intermediates are formed in the visible region at pH 9.1. Using time-dependent chemical-quench with mass spectrometry, the intermediates were correlated to the formation of cysteine sulfinic acid and cysteine sulfonic acid. This is the first evidence of a single domain enzyme acting as a trioxygenase. Altogether, a detailed mechanism of CDO has been developed.

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  • Have your cake and eat it too : the treatment of contemporaneous relationships under the Property (Relationships) Act 1976

    Reid, Adrianne Nicola (2007)

    Honours Dissertation thesis
    University of Otago

    Although it is clear from the Act that a person can be in more than one qualifying relationship at a time, the courts have shown themselves to be reluctant to recognise contemporaneous relationships as falling within the ambit of the Act. Because of this, contemporaneous relationships will only be recognised where it is abundantly clear that the parties are living together as a couple. Sections 52A and 52B are designed to divide property between relationships, and do not override the usual rules governing the division of relationship property between the partners in a relationship. Sections 52A and 52B will apply after the court finds that the relationship property of contemporaneous relationships overlap, and they will only apply to those pieces of property which are found to be relationship property of both relationships. The first limb of the rule in sections 52A and 52B will be redundant as all property that is relationship property of a relationship is attributable to that relationship. Property which is relationship property of both relationships will be divided between the relationships in accordance with their respective contributions to its acquisition. Sections 52A and 52B work to the advantage of the common partner, leaving them with half of the total relationship property. Because sections 52A and 52B only apply if the court has made findings in respect of each relationship, it is to the advantage of the common partner to litigate both disputes simultaneously, rather than undergo successive settlements with each partner. Sections 52A and 52B can also be used to manipulate the outcome where only one of the relationships has ended, or, in the case of the common partners' death, where one of the partners has an interest in retaining as much of the relationship property as possible between themselves and the deceased common partners estate. Given the difficulties in applying sections 52A and 52B, and their fairly arbitrary outcome, they would be better replaced with an unambiguous provision which allocated specified shares to the relationships on a more objective basis. [Extract from Introduction]

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  • Associations between dietary electrolytes and pulse wave velocity

    Lewis, Victoria (2017)

    Masters thesis
    University of Otago

    Background: Pulse wave velocity (PWV) is a non-invasive measure of arterial stiffness, and a recognised predictor of cardiovascular morbidity and mortality. Given this, it is likely that investigating the determinants of PWV will improve our understanding of cardiovascular health. At present, there is disagreement regarding the relationship between dietary sodium and potassium intakes, and PWV. Hence, further research is needed in order to confirm whether dietary sodium and potassium are determinants of PWV. Objective: The aim of this cross-sectional study was to investigate the associations between dietary sodium and potassium intake, and PWV in the general population. Methods: This cross-sectional study used baseline data from Health And Bread Intervention Trial (HABIT). Spot urine samples were used to estimate dietary sodium and potassium intake. Weighed three-day diet records were analysed for self-reported dietary sodium and potassium intake. Brachial blood pressure, and carotid-femoral PWV were measured with the SphygmoCor 2000. Results: Sixty-five HABIT participants were included in this study. Overall, 52.3% were males, with a mean±SD age of 34.5±18.3years, body mass index (BMI) of 24.9±4.5kg/m2; BP of 126.5/74.8±17.7/11.2mmHg, and PWV of 7.2±1.6m/s. Mean sodium intakes as assessed by spot urine samples and diet records were above New Zealand’s Upper Limit of 2300mg/day (urinary sodium: 3021±756mg/day; dietary sodium: 2784±1067mg/day). Mean potassium intakes, also assessed by spot urine samples and diet records, were below the Adequate Intake for New Zealand of 3800mg/day for males and 2800mg/day for females (male, urinary potassium: 2002±386.9mg/day; male, dietary potassium: 3500±1242.2mg/day; female, urinary potassium: 1902.6±428.5mg/day; female, dietary potassium: 2783.3±991.3mg/day). Dietary intakes of sodium, potassium, and sodium-to-potassium ratio as assessed by spot urine samples and diet records were not independently associated with PWV. In multi-variate analysis age was positively associated with PWV (a 1-year increase in age was associated with a 0.05 m/s increase in PWV). Conclusions: This small cross-sectional study found dietary intakes of sodium, potassium, and sodium-to-potassium were not independent predictors of PWV, suggesting the prediction of PWV is multi-factorial. Future adequately-powered studies should examine these relationships.

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  • The Totara House Healthy Eating Study: A qualitative investigation into the feasibility of adapting the Senior Chef programme for patients in a mental health setting.

    Borich, Aimee (2017)

    Masters thesis
    University of Otago

    Background: People experiencing early or first episode psychosis (FEP) are at increased risk of metabolic complications resulting from an interaction of illness symptoms, medication side-effects and lifestyle choices. Few studies have explored practical lifestyle interventions utilising nutrition education strategies to improve health outcomes in this population. This study aimed to assess the feasibility of implementing a healthy eating intervention programme in Totara House (a CDHB outpatient service for young adults with first episode psychosis by analysing stakeholder feedback, to determine whether a programme could be developed from a pre-existing learn to cook programme Senior Chef. Methods: Participants involved key stakeholders of Totara House: staff, patients and family members/carers, who were recruited by advertisement or through recommendation from Totara House staff. A combination of individual interviews amongst patients and caregivers and a single focus group amongst staff members was used to explore participant thoughts, opinions, values and experiences, about the importance of nutrition (in this population), and suggestions for programme component ideas. Participants completed a questionnaire to assess their current level of nutrition knowledge. Results: The data were analysed using thematic analysis. Three main themes emerged: “Personal Values” which explored patient worldviews, motivators and barriers; “Knowledge and Experiences of Health and Nutrition” which covered factors that can influence patients’ thoughts and attitudes towards achieving health goals; and “Programme Specific Details” included recommendations from participants for what they wanted to see in a healthy eating intervention programme. These themes and values support implementing a programme with a relaxed social atmosphere, including relevant practical information, and simple, affordable, healthy recipes they can try out at home. The questionnaire scores showed an average level of nutrition knowledge amongst all groups with a mean score of 53% (n=24). A one-way ANOVA revealed no between group differences (p= 0.46): patients 49% (n=8), staff 55% (n=10), family/carers 56% (n=6)), range 32%-73%. Conclusion: A healthy eating intervention programme would be highly valued by Totara House staff, patients and family members/carers. The feedback for the desired programme content aligned with the pre-existing Senior Chef model indicating its potential adaptability into this population. To ensure that the content adheres to current evidence-based nutrition advice, a registered dietitian should be involved in developing, running or overseeing the programme.

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  • Associations between aspects of body image and lifestyle behaviours and attitudes in Otago adolescents

    Bensley, Rachael (2017)

    Masters thesis
    University of Otago

    Background: Little is known about how New Zealand adolescents feel about their eating and bodies and how it is associated with body composition. Objective: To determine the association between food, feelings, behaviours and body image and (a) body composition and (b) other related factors in Otago adolescents. Design: Six hundred and eighty one adolescents between the ages of 15-18 years completed the Otago Students Secondary School Lifestyle Survey 2 (OSSLS2) in 2011. Height and weight were measured by trained research professionals. For this study we examined four subscales from the Food, Feelings, Behaviours and Body Image Questionaire (FFBBQ): concern about eating and weight; fear of weight gain; dietary restraint; and figure dissatisfaction. Associations between the four subscales and body composition, gender, physical activity, attitudes towards healthy eating and Diet Quality Index (DQI) scores were investigated using regression models. Results: There were significant differences in scores for concern about eating and weight, fear of weight gain, dietary restraint and figure dissatisfaction for males and females, and those at different weight status. Overweight and obese adolescents and female adolescents had significantly higher scores for all four subscales (all P>0.001) compared to normal weight adolescents and male adolescents, respectively. Overweight, obese adolescents and female adolescents were more concerned about their weight, practiced more dietary restraint, were more afraid of weight gain and were more dissatisfied with their figure. While 54% of female adolescents felt their body was “too fat”, only 28% of the females surveyed were classified as overweight or obese. While 26% of the males surveyed were overweight or obese, only 22% of males felt their body was “too fat”. Those who were meeting the physical activity guidelines had significantly lower figure dissatisfaction and concern about eating and weight scores. There were no statistically significant findings between any of the subscales and DQI score or attitudes towards healthy eating. Conclusion: There is a high prevalence of body dissatisfaction among Otago adolescents, which was more common in girls than boys, and not restricted to those carrying excess weight. Those who met the guidelines for physical activity reported lower figure dissatisfaction and less concern about eating and weight, compared to those not meeting the guidelines.

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  • A Kitchen-Based Validation of the Food Skills Component of a Food Literacy Questionnaire in New Zealand Children

    Govan, Alexandra Mary (2017)

    Masters thesis
    University of Otago

    Background: Food literacy is a recently developed concept which has emerged as a means to combat the rise in obesity and diet-related disease. Its purpose is to arm the public with a wide range of skills, knowledge and behaviours which are crucial to safely navigate today’s food environment. In 2015, a questionnaire was developed to measure the food literacy of New Zealand children, consisting of three components: food origins, food and nutrition knowledge and food skills. Of these three components, food skills are a practical skill which can be empirically validated, making it possible to ascertain whether the food literacy questionnaire accurately measures children’s food skills. Aim: To validate the food skills section of an online food literacy questionnaire, by comparing results from the food skills section of the food literacy questionnaire to practical food skills measured in a kitchen environment. Methods: A sample of 30 Year 6 children from two Dunedin schools were recruited. The participants initially completed the online food literacy questionnaire during school time, which was followed by participating in an hour-long food skills session one week later. The food skills sessions involved participants completing six ‘stations’ which assessed a range of food skills. These stations included: making a mini pizza, peeling and chopping a carrot, choosing the three main ingredients used in spaghetti bolognese, identifying foods that require cooking before consumption, boiling pasta until it is cooked, adjusting and following a pikelet recipe, and making porridge from an individual sachet by following the packet instructions. The results from the food skills sessions were then compared to the children’s results from the food skills section of the food literacy questionnaire. Results: The mean score from the food skills section of the food literacy questionnaire was 77%, and the mean score from the food skills session was 78%. The overall correlation between the food skills section of the food literacy questionnaire and the food skills session was 0.82 (p-value <0.001), indicating a high correlation. When participant scores were split into tertiles, 70% of participants were correctly classified in the lower tertile, and 60% in the higher tertile; only 10% of participants were grossly misclassified. Conclusion: The food skills section of the food literacy questionnaire is a valid measure of food literacy in Year 6 New Zealand children. It can correctly measure children’s food skills, as shown by an overall correlation of 0.82. The methodology of this research could be a useful tool for measuring children’s food skills in possible future food skills interventions and adopted to evaluate the effectiveness of these interventions.

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  • Food Literacy in New Zealand School Children: Nutrition Knowledge

    Russell, Kristina Louise (2017)

    Masters thesis
    University of Otago

    Background: Obesity rates in both children and adults have increased in recent decades in New Zealand. Changes in lifestyle and environment have meant that the frequency of convenience food consumption has increased and food skills and knowledge are often not passed down to younger generations. Food literacy is a new term encompassing the knowledge, skills, and behaviours needed to prepare and consume healthy foods. Developing food literacy in children is critical to slowing the rates of childhood obesity.To date, there is no data measuring how food literate children are in New Zealand. Objective: To measure the food literacy of a sample of Year 6 children in New Zealand Design: Cross-sectional observational study in three urban centres Method: A previously validated online 37-item questionnaire comprised of 7 food origin, 15 nutrition knowledge, and 15 food skill questions, plus 7 demographic questions was used to measure food literacy. Schools in Christchurch, Auckland and Wellington were randomly selected and Year 6 children invited to participate. During school hours, children completed the questionnaire either on iPads or personal devices and had their height and weight measured. A marking schedule was developed and used for scoring the questionnaire; each question had a total score of 1. Mean scores for each question and section were determined and analysed to identify the food literacy strengths and weaknesses of the children. Results: Children from 44 schools in Christchurch (n=198), Auckland (n=331) and Wellington (n=329) participated for a final sample size of 858 children. Children scored an average of 66% percent overall and 56% in the 1 nutrition knowledge section. Children displayed good knowledge with regard to interpreting food labelling (0.83/1.00) and common nutrition messages (0.75/1.00), as well as the knowledge of food groups (0.74/1.00). Lowest scoring areas were the awareness of dietary guidelines (0.25/1.00) and the knowledge of sugar content in diet cola (0.16/1.00). Conclusion: This is the first study to measure the food literacy of New Zealand children. These results can be used to guide future education programmes, however, they need to be interpreted with caution, as the sample contained a high proportion of children of “New Zealand European and Other” ethnicity from high decile schools. The focus of future interventions should be to increase children’s ability to identify healthy options and build on the demonstrated strength of label reading to aid this.

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  • Effect of long-term exercise training on zinc status: A systematic review

    Varma, Trishala (2017)

    Masters thesis
    University of Otago

    Background: Zinc is an essential trace element with many functions in the body, including energy metabolism, immunity and antioxidant activity. Regular exercise is a common recommendation for the prevention of chronic diseases, with irrefutable benefits. Zinc has a central role in exercise, however some groups of active individuals have suboptimal zinc status. Effects of short-term exercise on zinc status have been well documented, however effects of long-term exercise training on zinc status in the literature have been conflicting. Objective: To evaluate the effects of long-term exercise on zinc status, in trained compared to untrained groups. Design: We conducted a systematic review of peer-reviewed articles up to January 28, 2016 to identify studies that investigated effects of long-term exercise training on zinc status. Results: Six studies were included in the systematic review. Serum zinc did not display consistent results in the included studies in response to exercise training. There was a greater increase in urinary zinc excretion, erythrocyte zinc, dietary zinc intake and the activity of copper-zinc-superoxide dismutase in some groups undergoing exercise training, compared to the control group. Conclusion: The present review indicates that some zinc markers exemplify that there is a change in zinc homeostasis that occurs with exercise training. Further research is required to determine if these fluctuations warrant a change in dietary requirements for active individuals, and to allow dietitians to create best possible intervention plans for optimal health and/or physical performance.

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