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Epicardial adipose tissue morphology diversity in Māori, Pacific and New Zealand/European post mortem cases
No full textObesity is a global epidemic, and is the leading risk factor for heart disease and associated morbidities in New Zealand. Furthermore, Māori and Pacific New Zealand populations are up to 8 times more likely to develop both conditions. Obesity is characterised by an increase in fat (adipose tissue) throughout the body, both viscerally (surrounding organs) and subcutaneously (beneath the skin). Epicardial Adipose tissue (EAT) is a form of visceral fat located within the heart’s pericardial cavity, meaning EAT and the myocardium, maintain a unique, intimate relationship. This relationship has highlighted EAT as a possible tool in diagnosing cardiovascular disease. Recent studies found that obesity-induced morphological changes to EAT are dissimilar to those seen in other subcutaneous or visceral adipose tissues. In obesity, while adipocyte size increased in subcutaneous, appendicular and pericardial adipose tissues, EAT adipocyte size remained unchanged. Additionally, the well-established increase in overall EAT thickness in relation to body mass index (BMI), was not observed in Māori nor Pacific New Zealanders. This finding may provide insight into the disproportionate cardiac health outcomes for Māori and Pacific peoples in New Zealand.
My study aimed to investigate how obesity effects EAT morphology and cardiac localisation, and how these potential changes in EAT might coincide with cardiac remodelling (myocardial adipocyte infiltration and fibrosis) and cardiovascular disease prevalence in diverse ethnic populations in New Zealand. Additionally, my study aimed to uncover any novel correlations between EAT morphology/localisation, cardiac remodelling and anthropomorphic variables such as age and sex. I hypothesised that in post mortem cases, NZ/European, but not Māori nor Pacific would demonstrate a linear relationship between BMI and mean adipocyte size only in non-epicardial adipose tissues (subcutaneous, appendicular and pericardial). Additionally, I hypothesised that Māori and Pacific cases would present with a greater percentage of myocardial adipocyte infiltration and fibrosis than their NZ/European, age and BMI matched counterparts.
Statistical analysis of adipocyte and left ventricular histology from 91 post mortem cases revealed that mean subcutaneous, appendicular and pericardial adipocyte size positively correlated with BMI in NZ/European and Māori populations, while not in Pacific populations. A significant correlation was identified between the percentage of myocardial adipocyte infiltration and mean EAT adipocyte size in Māori/Pacific but not in NZ/European populations. Interestingly the opposite was seen in relation to myocardial fibrosis where subcutaneous and visceral (appendicular, pericardial, epicardial) adipocyte size significantly correlated with myocardial fibrosis in NZ/European, but not Māori/Pacific populations. Lastly, NZ/European cases showed a significant correlation between heart weight and BMI, while Māori/Pacific cases did not. In conclusion, the observed differences in adipocyte morphology/localisation between Māori, Pacific and NZ/European cases, highlight possible physiological differences, which could associate with potential differences in risks factors and disease characteristics between populations. My findings question the efficacy of current methods for diagnosis and treatment of heart disease and obesity, in all New Zealanders. My research illuminates the unconscious bias present in New Zealand healthcare, and highlights the need for more Māori led initiatives in both research and clinical practice, to facilitate the provision of equitable healthcare for all
Ecology of community: Exploring principles of socially-based tenure in urban papakāinga and cohousing communities
No full textSocial (or communal) tenure refers to systems of rights which are based on social norms, processes and relationships. Social tenures are a feature of many Indigenous cultures, where land and resources are managed from a collectivist, rather than an individualist, standpoint. For instance, in New Zealand, Māori society was traditionally based around territorial tribal living, with hapū (sub-tribes) controlling and defending particular territories. Western governance ushered in by Te Tiriti o Waitangi eroded this form of living by favouring individualised land tenure, and individualised tenure, private ownership and commodification have since tended to dominate the literature on housing and property. A danger of individualised systems is that they often separate land rights from social connections, responsibilities and relationships – you can be an unpleasant neighbour without compromising individual property rights. This begs the question of whether there are ways in which elements of socially-based tenure can be reintroduced within a contemporary context.
Based on a series of in-depth interviews, spatial analyses and field observations, this thesis investigates elements of socially-based tenure and how they are embodied in urban papakāinga (Māori housing) and cohousing communities. Despite differing origins, papakāinga and cohousing models share goals of enacting social facilitation, cohesion and whanaungatanga (relationships). Thus, a dialogue between the two models has merit in uncovering common lessons, as well as for identifying areas of tension and uniqueness. This thesis makes an original contribution to knowledge as the first in-depth study exploring the similarities and differences of urban papakāinga and cohousing models, and highlights the diversity of residents’ lived experiences. This diversity suggests a regionality or specificity of community outcomes, beset by a few core, potentially universal, principles.
Findings from this thesis have the potential to inform the wider New Zealand planning and housing debate, and to inform future housing development in our cities, both by Māori and non-Māori, in more socially-connected ways
Culture integration in post-M&A: The case of Chinese healthcare companies
No full textWhile the adjustment of the financial, capital and market structure ensures firms’ control rights after merger and acquisition (M&A), organizational culture as an informal system can profoundly affect the control rights of the company from the values, business philosophy and code of conduct，and even business performance. If there is no effective cultural integration, the conflict between the two sides due to corporate cultural differences will inevitably result in the lost in talent people, customer resource and other advantages.
This research attempts to examine culture integration in post-M&A in Chinese healthcare industry by proposing a cultural integration based on core capabilities. Drawing on merger and acquisition integration theory, this research identifies the key factors that affect the success of merger and acquisition integration. Through theoretical deduction and empirical analysis, this research explains the internal logical relationship between post-merger and corporate performance is explained. This research finds that corporate culture is the sum of corporate values, corporate systems and codes of conduct formed in the long-term survival and development of the company. The corporate culture can be explained into three levels: corporate ideological culture, corporate institutional culture and corporate image culture. Among them, ideological culture includes three indicators such as values, ethos and goals; institutional culture includes three indicators including work system, responsibility system and special system; and image culture includes office environment, brand identity and other images.
In terms of research design, this study explores the evaluation of corporate culture integration after mergers and acquisitions by employees in the medical industry through questionnaires, and establishes a comprehensive evaluation system for corporate culture integration after mergers and acquisitions. In addition, this research uses expert interviews, Delphi method, and fuzzy multi-level analysis (Fuzzy AHP) to evaluate the key to corporate cultural integration after mergers and acquisitions, and analyzes experts’ evaluation of the corporate culture of the three companies acquired by Century Galaxy Difference. The research results show that Century Galaxy Company has a good corporate culture integration after the merger. The key to the integration of corporate culture lies in the integration of ideological culture, followed by institutional culture, and finally image culture. Further research found that the overall evaluation of Century Galaxy Company's corporate culture is superior to the three companies A, B, and C of the merger. In particular, Century Galaxy Company is superior to the three M & A companies in terms of ideological culture and institutional culture, but not so in the image culture. Therefore, in terms of integration of corporate culture, Century Galaxy Company's merger and acquisition of three companies can achieve the merger and acquisition performance from the integration of ideological culture and institutional culture. Century Galaxy Company can improve the self-image culture with the help of the original good image culture of the three companies.
The evaluation framework established by this research can be used as a systematic method that can be used in the integration of corporate mergers and acquisitions and can provide an index reference for the management of mergers and acquisitions after mergers and acquisitions. Through the calculation of the main indicators of corporate mergers and acquisitions integration, the lack of existing corporate culture evaluation literature is supplemented. This provides some directions for the further development of the cultural integration assessment framework.
KEY WORDS：M&A; Corporate culture; Cultural integration; M&A performance; Medical industr
An Exploration of Mental Health Promotion in New Zealand: A Qualitative Study
No full textMental health promotion employs a strengths-based approach and focuses on promoting positive mental health. The current level of knowledge and reporting about mental health promotion efforts occurring in New Zealand is limited. Much of the attention is focused on national initiatives, with little attention or understanding of other health promotion interventions that may be more community focused or smaller in scale. Given this dearth, and the growing rates of mental ill-health in New Zealand, it is important to develop a comprehensive understanding of mental health promotion action in New Zealand.
This thesis sought to explore what health promotion practitioners are currently doing to address mental health in New Zealand, in terms of both content and practice. Semistructured interviews were conducted with fifteen health promotion practitioners employed at various organisations in New Zealand. Participants were selected using a combination of maximum variation and snowball sampling methods. Interview transcripts were thematically analysed using both inductive and deductive data analysis methods.
Interviews with health promotion practitioners revealed a diverse range of mental health promotion action occurring within New Zealand. The majority of programmes/projects were focused downstream, at the individual level, on developing personal skills. Mental health promotion programmes/projects involving community action, the reorientation of health services, and/or building healthy public policy were reported far less frequently. The findings of this study also revealed that health promotion practitioners in New Zealand have a sound knowledge and understanding of mental health and best practice health promotion. However, interviews highlighted various factors, operating at the systems level, that restricted health promotion practitioners from being able to translate this knowledge into their practice. Health promotion practitioners reported operating within short-term and prescriptive contractual agreements, a tertiary-focused health care system, a fragmented field, and a limited workforce, which created significant challenges for their mental health promotion practice. Particular practices impacted included health promotion practitioners’ equity- and Treaty-based practice and their evaluation capacity.
Overall, the findings from this research offer important insights into mental health promotion action occurring in New Zealand. They highlight a number of opportunities for future mental health promotion action, practice and research. Most pertinently, they highlight the need for system level action to address the system level factors restricting health promotion practitioners’ practice
Social Functioning in Attention Deficit Hyperactivity Disorder: Examining the Effects of Working Memory and Perspective-Taking
No full textAttention deficit hyperactivity disorder (ADHD) is a common childhood disorder that is associated with secondary difficulties extending beyond the diagnostic criteria, including impairment in social functioning. Currently available interventions are typically unsuccessful in reducing social difficulties in ADHD, and it is therefore important to explore factors that contribute to social impairment above and beyond symptom severity. Numerous contributors in non-clinical populations have been established in past literature, including strong links to cognitive abilities. Two cognitive abilities in particular have been previously associated with social functioning; working memory and perspective-taking. In turn, working memory capacity has been found to significantly predict perspective-taking ability. The current study aimed to explore the contributions of working memory and perspective-taking to social functioning in school-aged children with varying levels of inattention and/or hyperactivity. Participants were 100 children aged between 6 and 12 years old. Parent and teacher ratings of social functioning were obtained using a standardised measure, and children’s perspective-taking and working memory were obtained through objective measures of ability. As expected, correlation analyses found all study variables were related to each other. Further, working memory made unique contributions to perspective-taking, and perspective-taking made unique contributions to social functioning, over and above symptom severity. The hypothesis that working memory would mediate the relation between symptom severity and perspective-taking was partially supported. The hypothesis that perspective-taking would mediate the relation between symptoms and social functioning was also partially supported. The findings are discussed with reference to their implications for practice, and future research possibilities are suggested
THE NEW ZEALAND UNDERGRADUATE OBSTETRICS AND GYNAECOLOGY CURRICULUM
No full textAims of New Zealand O&G curriculum collaboration
To ensure and continue to improve quality and consistency of learning outcomes in Obstetrics and Gynaecology on a national basis
To inform the Medical Council of New Zealand of a national undergraduate curriculum in Obstetrics and Gynaecology
To continue to develop common teaching-learning materials that are appropriate for the discipline
To achieve efficiencies in the development and updating of learning resources noting the small academic workforce nationally in the disciplin
Expression of O-linked N-acetylglucosamine in the Rat Brain during Pregnancy and Lactation
No full textDuring pregnancy, adaptations occur in the maternal brain and body to ensure optimal nutrition for both the mother and fetus. Over nutrition in the mother can lead to gestational diabetes mellitus (GDM). GDM in mothers is a significant risk factor for development of cardiovascular disease and pre-eclampsia (Carr et al.,2011).
The protein modification O-linked N-acetylglucosamine (O-GlcNAc) is derived from glucose through the hexosamine biosynthetic pathway (HBP) and has been shown to increase in hyperglycemic conditions and plays a role in the etiology of many diseases, including T2DM (Hart et al., 2011). Research on the changes of O-GlcNAcylation during pregnancy and lactation is scarce.
My study aimed to determine any changes in O-GlcNAc expressing cells during the physiological conditions of pregnancy and lactation in the rat brain. I hypothesised that there would be an increased number of O-GlcNAc expressing cells during pregnancy due to higher blood glucose levels, which would normalise or decrease during lactation compared to non-pregnant rats.
Female Sprague Dawley rats were divided into 3 groups (diestrus, 21 days pregnant and day 7 lactating), perfused with 4% paraformaldehyde, brains removed and coronally sliced for immunohistochemistry. Single-label chromogen staining for O-GlcNAc was carried out in the ventromedial hypothalamus (VMH), paraventricular nucleus (PVN), supraoptic nucleus (SON), periventricular nucleus (Pe) and the anteroventral periventricular nucleus (AVPV). Single-label immunofluorescence for O-GlcNAc was carried out in the arcuate nucleus (ARC). Sections were photographed and analysed using FIJI (Image J) to count the number of O-GlcNAc expressing cells in each area. There was no statistical difference between the number of O-GlcNAc expressing cells in pregnant and lactating rats compared with non-pregnant rats in the ARC, PVN, SON, VMH, Pe and AVPV.
Double-label immunofluorescence for O-GlcNAc and DeltaFosB, a marker of chronic activation, was also carried out in the PVN. The average number of DeltaFosB expressing cells and O-GlcNAc expressing cells were counted, no difference was detected between the non-pregnant, pregnant and lactating groups. Furthermore, the percentage of DeltaFosB cells co-expressing O-GlcNAc and the percentage O-GlcNAc cells co-expressing DeltaFosB revealed no difference between the non-pregnant, pregnant and lactating groups. The results from our study suggests that in a normal rat pregnancy and subsequent lactation the expression of O-GlcNAc does not differ from non-pregnant expression
Self-management outcome measures for children with inflammatory bowel disease
No full textPaediatric Inflammatory Bowel Disease (IBD) can significantly affect a child’s physical and psychological well-being, and the incidence is increasing globally. An emerging focus of paediatric IBD care that has the potential to improve disease outcomes is that of self-management, whereby children are encouraged to develop skills and attributes to enable them to manage their own disease and treatment. Self-management comprises a number of intertwined elements; knowledge, adherence, self-regulation, and communication. In order to provide targeted support in these areas’ children should be frequently assessed to highlight gaps or misconceptions that may affect their disease outcomes. Few self-management outcome measures are available for this population group. The aim of this research was to undertake a series of projects to develop and validate assessment and reporting tools that address components of self-management in order to provide targeted education and support for children with IBD. This research also contributed to the design of a mobile health app that is aimed at encouraging children with IBD to self-manage their disease.
Section one explains the detailed, iterative development process of a mobile health app aimed at encouraging self-management for children with IBD: IBD-Tracker.
Section two presents the development process of a knowledge assessment tool for children with IBD: IBD-KID2. A series of studies were performed to assess the validity, reliability, feasibility, and generalisability of IBD-KID2, as well as testing IBD knowledge levels in different population groups.
Section three details the development of a symptom self-report tool for children with IBD that uses a series of text and pictorial Likert scales that enables children to report their IBD symptoms: IBDnow. A study performed in two tertiary paediatric IBD centres showed that children from the age of three years can use IBDnow to produce symptom reports with a good level of agreement to reports from their gastroenterologist when using standard validated clinical tools.
Section four contains a systematic literature review undertaken to identify self-management skills assessment tools specific to the target population, none of which were appropriate for use with younger children with IBD. Using the available evidence, a novel self-management skills assessment tool was developed: IBD-STAR. A content validity evaluation by a series of experts appraised the relevance, appropriateness, and likely effectiveness for the target population. A study then compared the children’s skills assessment using IBD-STAR with an assessment undertaken by their parents, and gastroenterologist. This showed that children’s reported skills using IBD-STAR correlated well with their gastroenterologist’s assessment, but their skills were underestimated by their parents.
Section five assessed whether the content of the mHealth app IBD-Tracker, when delivered in an alternative format (booklet) was effective and acceptable regardless of the mode of delivery. The results highlighted a positive trend towards improving self-management outcomes, but the response rates and feedback suggest that interventions aimed at children should prioritise engagement in addition to ensuring a strong evidence base for the content.
Children with IBD should have multi-disciplinary support as they develop self-management skills. This series of studies has provided a number of outcome measures to address the various components of self-management for children with IBD that will highlight where targeted interventions, such as a mobile health app, may be effective
The iron intakes and likely bioavailability of iron in vegetarian and non-vegetarian adolescent women in New Zealand
No full textBackground: Adolescent women are vulnerable to iron deficiency, including iron deficiency anaemia, and those who follow a vegetarian diet may be at even greater risk due to the lower bioavailability of iron in vegetarian diets. To date, no study has explored the iron intakes or likely bioavailability of iron in the diets of vegetarian adolescent women in New Zealand.
Objective: To compare, in vegetarian and non-vegetarian adolescent women 15-18 years of age in New Zealand: intakes of dietary and total iron; the prevalence of inadequate iron intakes; intakes of haem iron, non-haem iron, and selected iron absorption modifiers; intakes of estimated available iron; and the main food sources contributing to iron intake.
Design: The SuNDiAL (Survey of Nutrition Dietary Assessment and Lifestyle) study is an ongoing cross-sectional survey of adolescent women 15-18 years of age from eight cities in New Zealand. Participants in the current study were enrolled between 18 February 2019 and 4 September 2019. Dietary intakes were assessed using two 24-hour recalls, and were adjusted to reflect ‘usual’ intake using the Multiple Source Method. Supplement iron intakes were estimated using information from an online questionnaire. The prevalence of inadequate iron intakes was estimated using the full probability approach, using information on total iron intakes (from dietary sources and supplements). Intakes of available iron were estimated using the Monsen and Balintfy algorithm. Comparisons were made by self-defined vegetarian status.
Results: The current study comprised 31 vegetarians and 219 non-vegetarians. Only 59% of the vegetarian participants reported never consuming flesh foods currently. When compared to non-vegetarians, vegetarians had a higher estimated mean total iron intake (difference [95% CI]: 21% [2 to 42] (reported as a percentage because data are log transformed); P=0.026), and a lower estimated prevalence of inadequacy (12% vs 21%). However, intakes of several dietary factors that influence iron bioavailability differed between groups: vegetarians reported lower mean intakes of haem iron (-0.99 mg/d [-1.20 to -0.79]; P<0.001) and ‘Meat, Fish, and Poultry’ (-102.8 g/d [-118.5 to -87.1]; P<0.001), and higher mean intakes of fibre (as a proxy for phytate; 5.25 g/d [1.55 to 8.95]; P=0.006), and also vitamin C (by 26% [1 to 58] (reported as a percentage because data are log transformed); P=0.04), than did non-vegetarians. The estimated mean iron bioavailability of vegetarian diets was statistically 20% lower than that of non-vegetarian diets (7.7% vs 9.6%; P<0.001), and the estimated mean intake of available iron for vegetarians was numerically 11% lower (0.99 mg vs 1.11 mg) than for non-vegetarians (-0.12 mg/d [-0.28 to 0.03]; P=0.105). Vegetarians obtained a higher proportion of iron from plant-based food sources (particularly ‘legumes, nuts and vegetarian products’ and ‘grains and pasta’), and a lower proportion from flesh foods sources, when compared to non-vegetarians.
Conclusion: Although the vegetarians had higher total iron intakes than the non-vegetarians, the bioavailable iron content of their diets was slightly lower, suggesting that self-defined vegetarian adolescent women may be at greater risk for iron inadequacy than non-vegetarians. Further research is required to determine what impact this may have on biochemical iron status, and to generate findings that are more representative of adolescent women in the wider New Zealand population, including those who adhere more closely to a vegetarian diet
Modelling and inference for electromagnetic flow tomography
No full textElectromagnetic flowmeters determine the bulk flow rate of an ohmic fluid in a pipe by measuring the voltage induced across the fluid by a transverse magnetic field. This thesis develops the theory of an electromagnetic flowmeter for groundwater aquifer applications. Electromagnetic flowmeters require slow, laminar flow for measurements of bulk flow to be accurate - even after calibration. In general, the measured voltage depends on the spatial distribution of the velocity of the fluid. Hence, determination of the velocity field is required in order to accurately measure the bulk flow rate in general flows. Accordingly, this thesis examines the inverse problem of electromagnetic flow tomography, which is the problem of determining the velocity field in a fluid from voltage measurements made at multiple locations. Electromagnetic flow tomography is a severely ill-posed linear inverse problem.
The relationship between the flow and the potential induced across the fluid is described by the flowmeter equation - a boundary value problem in Poisson's equation, with the source due to the Faraday effect. A novel dipole-form of the flowmeter equation allows for analysis of spatial sensitivities. This boundary value problem is solved using Green's functions, derived by the method of images for the geometry of pipe cross-section and half-space. Computational implementation of the forward map uses a finite element method discretisation and assumes idealised point electrodes to simulate measurements. Analysis of the measurement kernel reveals extreme sensitivity to flow near the electrode locations, with low sensitivity to the majority of flow away from the electrodes. The resulting non-uniqueness in inverting the forward map implies that assumptions must be made about the spatial flow profile in order to make estimates of the bulk flow.
This thesis examines a Bayesian formulation to this inverse problem, that includes a model for the forward map, and accounts for measurement noise and uncertainty in the velocity field. The Bayesian analysis of an inverse problem produces the posterior distribution, from which estimates of desired quantities may be calculated, along with uncertainties. In particular, prior modelling allows for exploring assumptions and representation of unknowns to determine potential biases. The resulting Bayesian model is a standard stochastic hierarchical model with hyperparameters to model modelling uncertainties such as the smoothness of the flow profile, or other effects. The flow is modelled as a Gaussian Markov random field and the hyperparameters are modelled using a Jefferys prior.
The resulting model for the flow tomography inverse problem is a linear Gaussian model. Inference for this model is efficiently implemented using the recent marginal then conditional algorithm. That algorithm generates posterior samples by first using a Monte-Carlo Markov chain sampler for the low-dimensional marginal distribution over hyperparameters, then drawing from the full conditional distribution over the flow profile, which requires one solve of a linear equation. Posterior inference does not require the draw from the full Gaussian conditional, as moments of the Gaussian are available analytically. This method for computational Bayesian inference surpasses equivalent regularising methods in computational speed.
To the best of this author's knowledge, this is the first time a Bayesian method has been used for analysing electromagnetic flow tomography.
Measurements of the bulk flow in a pipe are computed using simulated data generated from physically sensible phantom flow profiles. Various geometries and electrode placements are examined, with different shapes and scales of phantom flow. The effect of using the fluid dynamics no-slip condition and changing hyperparameter values is also explored. Not surprisingly, increased number of electrodes increases the spatial flow profile resolution and accuracy of bulk flow estimates. The flow profile reconstructions and bulk flow estimates are more accurate for flow profiles which could easily be interpolated from values near electrode locations. Additionally, it is shown that there is an implicit scale in the system - the standard deviation of bulk flow correlated to the area of the pipe.
The use of invasive measurements for the purpose of measuring groundwater flow is also investigated. Analysis in this thesis shows that measuring groundwater flow presents significant difficulty; the resolution of bulk flow from a realistic signal-to-noise ratio is several orders of magnitude larger than the expected bulk flow rate in unconfined aquifers