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What are the barriers to equitable maternal health in Aotearoa New Zealand?
No full textBackground:
Aotearoa New Zealand has a socialised health care system with free at point of delivery maternity care. Care is also uniquely structured, led by autonomous, principally community based, lead maternity care midwives providing continuity of care. Yet, large maternal health inequities exist. Māori and Pacific women are over-represented in maternal mortality and morbidity statistics and patient experience is rated poorly by these groups.
Aim:
To investigate the barriers to maternal health equity in New Zealand.
Methods:
A four-phase research programme, using integrative methodology, began with an integrated review examining the setting for maternal health inequity in New Zealand. Next, the last maternal satisfaction survey (from 2014) was interrogated using structural equation modelling to investigate the influence of different aspects of access on maternal satisfaction. The third and most extensive phase used logistic regression modelling to examine relationships between social determinants of health and severe adverse maternal and perinatal outcomes, using data from the Statistics New Zealand Integrated Data Infrastructure linked administrative datasets from 2003 to 2018. Finally, through a Foucauldian lens, I critically analysed the embedded systems and processes that may enable health inequities to persist and inhibit progress in ameliorating them.
Results:
The review found that New Zealand maternal health inequity is situated in a complex context, comprising the unique maternity system and its acceptability, sparse geographic population distribution, neoliberal politics, cultural factors and a colonial history.
Structural equation modelling found some groups – especially young women, those in remote rural and/or high socioeconomic deprivation areas – were less satisfied with specific equity and access aspects often associated with poor maternal and perinatal outcomes.
In a dataset of over 950,000 births, marked inequities in maternal and perinatal outcomes were found. Once adjusted for demographic variables (socioeconomic deprivation, education, parity, age, rural/urban residence and ethnicity) Māori and Asian women had an adjusted odds ratio of 1.21 (95% confidence interval (CI) 1.18-1.23) and 1.39 (95% CI 1.36-1.43) for poor outcome respectively compared to New Zealand European/European women. Variables indicating lack of engagement with the healthcare system had the highest adjusted odds ratios of adverse maternal and perinatal outcomes. Over 20% of the birthing population in some geographic areas suffered a severe adverse outcome over this 16-year period.
Critical analysis demonstrated that women experiencing the poorest outcomes are also often considered ‘outside the norm’. In Foucauldian terms this allows labelling of some groups as aberrant and enables society to tolerate inequities for those considered ‘other’.
Conclusion:
This research, using large linked administrative datasets and novel methods (e.g., imputation using predictive mean matching), found maternal health inequity in Aotearoa New Zealand was strongly associated with social determinants, consistent with international evidence. These maternal health inequities continue as affected women are from groups that are marginalised by society. The critical analysis provided insight into systemic changes that are required to eliminate these inequities. At a policy level, urgent attention is needed to change systems to make accessing care safe and acceptable, in both primary and secondary services. And, as a society we must refuse to accept maternal health inequities as inevitable
What global perspective does our university foster in our students?
No full textWe used a modified circuit of culture enquiry to explore processes of production, representation and consumption of global perspective at our university, in the context of fostering this perspective as a graduate attribute. We identified four frame packages by which this perspective is understood and communicated. Global perspective is framed within our institution simultaneously as essentially cooperative and as competitive. We express concern about how such complexity is fostered in our students. We ask our colleagues and university teachers internationally to critically reflect upon the diversity of global perspectives extant within higher education and potentially to clarify their intentions as university teachers
New Zealand’s Food Waste: Estimating the Tonnes, Value, Calories and Resources Wasted
No full textWe used macro-economic data and aggregated waste data to estimate that, in 2011, New Zealand households generated over 224,000 tonnes of food waste, and New Zealand industry generated over 103,000 tonnes of food waste. We split New Zealand’s food waste into 14 food-waste categories and found that 7% is related to “fresh” produce, and 93% “processed” food waste. The value of New Zealand’s food waste in 2011 is estimated to be NZ 131 per person. Furthermore, New Zealand’s food waste represents 163 ˆ 109 calories in total, and avoidable food waste would be able to feed between 50,000 and 80,000 people a year. New Zealand food waste embodies 4.2 ˆ 106 tonnes of CO2-e, 4.7 ˆ 109 m3 of water, and 29 ˆ 103 TJ of energy. Nonetheless, we find that, compared to other nations, New Zealanders waste less food per capita by weight, value and calorie
The nature and influence of the hidden curriculum impacting SGM health learning in health professional education – A scoping review protocol
No full textThis document outlines the justification and process for a scoping review of current knowledge on the hidden curriculum relating to Sexual and Gender Minority health in health professional education. It includes a brief synopsis of the background literature, the aims, research questions, and methods of the planned scoping review. The purpose of this scoping review is to map the current literature relating to the nature and influence of the hidden curriculum on SGM health learning with a particular focus on undergraduate HPE
Development of nanofibres for local delivery of neuroactive drugs to the brain
No full textIntroduction: Drug delivery to the brain to treat neurological disorders is a challenge due to the blood-brain barrier, which physically and actively restricts the transport of molecules into the brain. Implantable drug delivery systems (e.g. hydrogels and nano/micro-particles) have been developed to overcome the blood-brain barrier issues. However, limitations such as excessive swelling or disintegration of the hydrogel, retaining the particles at the site of action, low loading efficiency and burst release of the drug can occur. Therefore, the overarching aim of this thesis was to develop and characterise implantable nanofibres (NF) for drug delivery to treat neurological disorders using low toxic solvent systems.
Methods: NFs were prepared using the technique of electrospinning using biodegradable polymers. For the first time, a new, low toxicity solvent system consisting of acetone (ACE) and ethyl acetate (EtAc) (Class III solvents) was used to prepare poly-(lactic-coglycolic acid) (PLGA) NFs. The electrospun PLGA NFs were characterised based on morphology, solid-state characteristics, tensile strength and hydrophobicity and compared to NFs electrospun using more toxic solvent systems of dichloromethane (DCM) and dimethylformamide (DMF) (Class II solvents). The incorporation and release kinetics of drugs with different molecular weights (paracetamol 151.17 g/mol, ampicillin 349.41 g/mol and tetracycline 480.90 g/mol) were investigated.
Poly-(caprolactone) (PCL) was also investigated as a NF drug delivery system and was co-electrospun with chitosan (CH), gelatine (GEL) or poly-(ethylene oxide) (PEO). The NFs were compared to determine if the blended polymers improved the chemical and physical properties of PCL NFs. In vitro degradation studies were conducted and the drug release kinetics of L-655,708 from PCL and the PCL/blend NFs was investigated. Further release studies from PCL/CH NFs were undertaken, with a comparison between the neuroactive-drug L-655,708 and indomethacin. The in vitro cytotoxicity and immune response assays were conducted to investigate the biocompatibility of the NFs.
Results: Compared to PLGA NFs produced using the conventional solvents DCM and DMF, the new ACE:EtAc solvent system resulted in NFs with a decrease in fibre diameter uniformity and an increased hydrophobic surface as determined by field emission scanning electron microscopy (FE-SEM) and water contact angle measurements, respectively. NFs made using both solvent systems were amorphous, however, the residual solvent could be detected by thermogravimetric analysis. Attenuated total reflectance-Fourier transform infrared spectroscopy analysis showed there was no change in PLGA chemical composition after electrospinning. Tensile strength studies showed that NFs prepared using the less toxic ACE:EtAc solvent system was lower in tensile strength and underwent a different mechanical deformation process compared with DCM:DMF NFs.
The solid-state analysis confirmed the incorporation of the drug in the PLGA NFs, with FE-SEM and hot stage microscopy identifying drug on the surface of the NFs. The drug release kinetics of tetracycline and paracetamol were similar from both NFs with an initial burst release, followed by a gradual release over 504 h. Assessment, however, of the release profile for ampicillin revealed a smaller initial bolus release with the release from PLGA ACE:EtAc being slower than PLGA DCM:DMF. The release kinetics indicated that the molecular weight of the incorporated drug, nor fibre diameter influenced drug release.
FE-SEM analysis of PCL and PCL/blend NFs showed smooth, bead-free NFs with average fibre diameter in the order of PCL/CH < PCL < PCL/PEO < PCL/GEL. The polymers incorporated into the NFs were chemically unchanged by the electrospinning process and the NFs did not appear to have residual solvent present. The PCL component of PCL/CH and PCL/GEL NFs had reduced crystallinity, while PCL/PEO NF was the most thermally stable and had the highest mechanical strength. The hydrophobic surface properties of the PCL NF were decreased when blended with PEO and GEL.
An in vitro degradation study revealed a reduction in mass of 44% and 38% from PCL/PEO and PCL/GEL, with negligible loss over the 4-weeks from PCL and PCL/CH. With polymer degradation said to influence drug release, it was interesting to observe that the degradation study did not translate into the faster release of L-655,708 from PCL/PEO or PCL/GEL, as PCL/CH showed the fastest release with 100% release after 24 h. The drug release from PCL/CH was further investigated as a charge interaction was postulated to be the mechanism of release, however, the release of the neutral drug indomethacin was similar to the release of L-655,708. Two theories were put forward to explain the release kinetics from the PCL/CH NF; 1) phase separation of the polymers occurred during electrospinning, forming two distinct fibres with the hydrophobic drugs favouring the lesser hydrophobic interaction with CH resulting in drug diffusion out of the CH NF. Alternatively, a core/sheath NF occurred where the drug was located in the CH sheath around a PCL core resulting in drug distributed at the surface of the NF. 2) During the electrospinning process, nano-pores were created on the surface of the NF that facilitated the diffusion of the drugs from the NF. In vitro cell culture studies showed PCL/GEL had the greatest cell proliferation over 24 h and the highest cell viability over 3 days. NFs with fibroblast cells cultured on the surface did not elicit an immune response, however further studies need to be conducted to confirm biocompatibility.
Conclusion: This thesis demonstrates the development of a drug delivery system using the electrospinning process that utilises less toxic solvent systems. Drug release was sustained over 21 days and supports the use of a NF as a promising candidate for the local delivery to treat neurological disorders
The impact of microplastics on larvae of the sea urchin Pseudechinus huttoni
No full textMicroplastic pollution in the marine environment is of increasing global concern and, therefore, determining the effect of its presence on marine organisms should be a research priority. Although ingestion and adverse effects of microplastics have been confirmed for multiple marine taxa, limited studies have assessed ingestion of microplastics by marine invertebrate larvae and the related effects. Determining the effects of microplastic ingestion by marine organisms, especially during the sensitive larval stages, is an important step in understanding wider ecosystem responses. Thus, in the present study 7- and 14-day post-fertilization (dpf) planktotrophic pluteus larvae of the sea urchin Pseudechinus huttoni were used as model organisms to investigate ingestion and retention of 1–5 μm fluorescent green spherical microplastics (10, 100, 1000, 10,000 mL-1). In addition, the lethal and sub-lethal responses of 7 dpf larvae to a short-term, 10-day exposure of 1–4 μm spherical polyethylene microplastics at varying concentrations (10, 100, 1000 mL-1) were evaluated. Survival, development, and oxidative damage were used as measures to identify adverse effects. Development was assessed by measuring nine different morphometric dimensions over the experimental period, while the difference in post-oral arm length was used as a measure for abnormal development. To identify the oxidative stress defence mechanisms activated in response to microplastic exposure, antioxidant enzymes, lipid peroxidation, and protein carbonylation in the whole- body tissues of P. huttoni larvae were assessed.
Microplastics were ingested by larvae in a dose-dependent manner and were retained for up to 90 (7 dpf larvae) and 150 min (14 dpf larvae) within the gut, before egestion. Survival, as measured by larval density, over the experimental period was not significantly affected by microplastic exposure at any of the concentrations tested. In contrast, following exposure to microplastics, a teratogenic response in terms of delayed development, resulted in an increase of larval arm asymmetry. Furthermore, detailed measures indicated body length and post-oral arm gap were significantly affected by microplastic exposure. More strikingly, short-term microplastic exposure resulted in oxidative lipid and protein damage in larval body tissue despite a significant upregulation of antioxidant defences, indicating the potential for oxidative stress biomarkers to be useful in future microplastic exposure research.
Results of the present study indicate the necessity to further investigate the effects of microplastic exposure on the early life stages of marine invertebrates, as well as broadening the experimental duration to include processes such as settlement and metamorphosis. Microplastic-induced adverse effects in these sensitive stages of their life cycle may have consequences on recruitment and ecosystem dynamics in the marine environment, however due to many knowledge gaps, particularly on the abundance of microplastics in the size range used in the present study, it is difficult to conclude to what degree microplastics are a threat. Moreover, the multiple stressors marine invertebrate larvae face in the marine environment need to be considered when interpreting results of microplastic exposure studies
Impact of light and water flow on the responses of coralline algae to ocean acidification
No full textCoralline algae are globally abundant components of benthic habitats and play foundational roles in coastal ecosystems such as temperate kelp forests and coral or rocky reefs, where they are often the dominant substrate cover. The emerging understanding of the sensitivity of coralline algae to ocean acidification (OA) has emphasised the need to determine the natural variability of parameters that could influence growth and reproduction of coralline algae in situ to improve experimentation as well as predictions of climate change outcomes for this group.
To identify spatiotemporal variability of seawater pH inside a Macrocystis pyrifera kelp forest, typical for southern New Zealand with high coralline algae cover, long term (> 1 year) pH, irradiance and temperature data were collected. Seawater pH was highly variable (pHT 7.45–8.49) and exhibited strong diel and seasonal differences that were associated with metabolic activity of the surrounding macroalgal community and linked to peaks of photosynthesis and respiration. These results show that coralline algae inhabit a highly variable environment, with occasional pH minima lower than end of the century predictions for the open ocean. Coralline recruitment peaked between late autumn and winter, when irradiance reaching the benthic communities was up to 85 % lower than during the summer months.
Despite the ecological importance of coralline algae in low light environments and their vulnerability to OA, there is limited understanding of how the interplay between irradiance and seawater pH influences coralline growth and reproduction. To determine these impacts, a 212-day experiment exposed coralline communities growing on artificial substrates to two pH levels (pHT 8.05 – present-day/ pHT 7.65 – OA scenario) and a gradient of daily light dose (0.35, 0.17 and 0.1 mol m-2 d-1), based on the light environment typical at depth during the months of peak recruitment. Coralline growth was highest in the intermediate irradiance treatments and growth was reduced in response to lowered seawater pH with net dissolution occurring in the lowest light treatments, while communities in the pHT 8.05 conditions continued to grow. Furthermore, recruitment resulting from these communities in the OA treatment was reduced by more than half. The reduction in recruitment in response to OA was amplified under reduced irradiance, and recruitment was near zero in the lowest light treatment at pHT 7.65. The decline in growth and recruitment was attributed to limited capacity to counteract the energetically costly OA induced dissolution. This shows that coralline communities may be increasingly at risk from OA in habitats where irradiance is low, such as cryptic habitats or at depth, where they represent the main substrate cover.
It has been proposed that habitats of reduced water flow may act as refuges for coralline algae, due to the possibility to metabolically increase pH in the immediate surrounding of the tissue when water flow is reduced. In a 220-day experiment the combined impacts of three flow rates and two seawater pH treatments (pHT 8.05 – present day/ pHT 7.65 – OA scenario) on the growth and recruitment of coralline communities were examined. Under the present-day pH scenario, flow treatments had little effect, while in the OA-scenario flow-dependent responses were evident. While growth of coralline communities was heavily reduced in the lowest flow treatment, coralline growth did not exhibit the same decrease in response to decreased seawater pH in the two higher flow treatments. Furthermore, lowered seawater pH and reduced flow synergistically decreased the number of recruits successfully establishing in the treatments. Reductions in flow exacerbated rather than ameliorate the effects of OA on coralline algae.
These results show that irradiance and water flow can exert strong influences on coralline algae under OA, with high susceptibility of coralline recruitment.
University foodservices’ potential for providing environmental education to students
No full textUniversity foodservices are potentially well placed to foster environmental education in a non-classroom setting and so could have the power to benefit communities through producing environmentally literate graduates. Buy-in from foodservice staff is critical for realising this potential, so understanding what foodservice staff think about their foodservice engaging in the provision of environmental education is essential. The aim of this study was to identify the dominant perspectives held by university foodservice staff about the desirability and realities of fostering environmental education in their workplaces. Methods: The study design integrated two phases: (i) 36 foodservice staff conducted a card-sorting activity that revealed four dominant viewpoints; (ii) 60 foodservice staff completed a survey where they identified with one of these viewpoints. The study was conducted in Dunedin, New Zealand. The four main perspectives were The ‘Believer’, the ‘Relatively Positive Integrator’, the ‘Uncertain Contender’ and the ‘Sceptic’. All of the perspective groups, except for Sceptic, believed environmental education in their workplace was desirable. In the survey, 25% of the 60 participants self-identified with the Believer narrative, 40% with the Relatively Positive Integrator, 25% with the Uncertain Contender and 10% with the Sceptic. There were no significant differences between factors for sociodemographic characteristics. A paradigm shift in foodservice framework thinking could unlock the potential university foodservice has to assist universities whose strategic mission is to embed environmental education in both curricular and co-extracurricula activities
Exploring the role of the circadian timing system in the control of metabolism and the consequence of lighting disruptions
No full textThroughout history, humans have been constantly driven by the rising and setting of the sun. Being able to anticipate this consistently changing environment is encompassed in our endogenous circadian clock. This system allows for the coordination of our physiology and behaviour to suit the environment around us. Human studies within the last few decades suggest that disruptions to this system increase the prevalence of metabolic disturbance, leading to the development of diseases such as obesity, diabetes, cardiovascular disease and their associated co-morbidities. Little is known about the mechanisms by which disruptions lead to an eventual degradation in the metabolic system.
This thesis first sought to characterise the effect that chronic light cycle disruptions have on metabolism. To emulate the human condition, I used a mouse model exposed to constantly shifting lighting environment, comprised of a 6-hour advance, occurring every 6 days, to chronically disrupt their circadian timing system. This treatment caused a gradual increase in body weight of 3.54 ± 0.34g after 12 phase shifts compared with mice under control lighting conditions gaining 1.97 ± 0.25g. Additionally, following the 5th phase shift, light cycle-disrupted animals showed a reversal in their diurnal pattern of energy homeostasis and locomotor activity followed by a subsequent loss of this rhythm. To investigate potential molecular mechanisms mediating these metabolic alterations, we assessed central leptin and insulin sensitivity. We discovered that light cycle-disrupted mice had a reduction in central leptin signalling sensitivity, as indicated by a reduction in the number of phosphorylated STAT3 immunoreactive cells in the arcuate nucleus of the hypothalamus. Furthermore, light cycle-disrupted animals exhibited a marked increase in fasting blood glucose from 108.8 ± 21.3mg/dl in control animals, to 269.4 ± 21.1mg/dl in animals under light disruption. Peripheral hyperglycaemia was accompanied by alterations in central insulin signalling at the level of pAkt and IRS1, suggesting that light cycle-disruption has a direct effect on metabolic signalling pathways within the brain.
Secondly, I sought to investigate the effect light cycle disruptions have on whole body glucoregulation. Mice were subjected to the same light cycle disruption schedule as previous, and glucose tolerance was assessed throughout the experiment. Glucose tolerance of mice under light cycle disruptions was altered from the 9th light cycle shift. Fasting blood glucose was elevated in animals under light cycle disruption (143.1 ± 4.8 mg/dl) in comparison to controls (110.2 ± 6.6 mg/dl), however, not to the same magnitude as in the previous cohort of mice. The loss in glucose tolerance is likely a direct result of the light cycle disruptions given that there was no increase in body weights above controls, in animals under light disruptive conditions.
Lastly, I aimed to assess the effect of disrupting either the light zeitgeber or the food intake zeitgeber, on metabolism. Additionally, I sought to ameliorate previously observed metabolic disturbances by intervening with strict feeding regimes. Mice were either fed ad libitum, restricted to the dark phase, or had a rotating window of food access, throughout the experiment. Of these, half the animals were subjected to light cycle disruptions, identical to previous experiments. Animals under light cycle disruption fed ad libitum gained 51 ± 5.3% increase in body weight compared to 40.7 ± 4.1% increase in controls, as well as an increase in fat mass relative to body weight. Interestingly, a third group of mice presented themselves during this study, that had a distinct phenotype difference when compared to wildtype animals. Animals deemed ‘NowShift’ were observed to shift their behaviour almost instantaneously following a shift in the lighting environment. These animals were also protected against light disruption induced weight gain, increasing by only 31.3 ± 6.2% across the experiment, in those fed ad libitum. Mice under light cycle disruption that had their food restricted to the dark phase gained only 21 ± 3.5% body weight from baseline, in comparison to controls that gained 27.9 ± 4.3% body weight from baseline. Animals in this group deemed as ‘NowShift’ were also unaffected by the lighting disruptions, gaining only 23.6 ± 3.8% body weight from baseline. Additionally, there were no differences in fat mass across all three groups. Animals with rotating access to food showed a reduced body weight in comparison to those fed ad libitum, likely due to a reduction in total food intake. These animals had a severely disrupted rhythm of food intake; however, little impact was seen in activity rhythms. Our findings suggest that light entrains and controls locomotor activity patterns, whereas food intake is a crucial entrainment cue for maintaining metabolic health. Forcing synchronisation of the food and light zeitgeber through time restricted feeding can ameliorate body weight increases observed in animals fed ad libitum. Finally, the spontaneous phenotype of NowShift animals was a surprise, however, the fact that these animals are protected from light disruption induced weight gain raises the question of the mechanism behind their genetic advantage. Exome sequencing was performed in these animals, however further investigation is required to identify potential genetic variants
Factors affecting young Chinese tourists' use of Airbnb and the impact of personal values: A motivation-based segmentation study.
No full textThe rise of the peer-to-peer accommodation service such as Airbnb has represented a transformational innovation in the tourism and accommodation industry. Guttentag and fellow researchers (2017) stated that limited research had examined Airbnb, and motivation-based segmentation research based on accommodation choice is much more limited. As a replication study, the purpose of the current research was to investigate why tourists choose to stay with Airbnb based on the 17 motivators proposed in Guttentag et al.’ study, but more specifically among young tourists in the Chinese context. In addition, this study investigated young Airbnb users' level of the importance of personal value items proposed by Schwartz (Schwartz, 1992), in order to study whether there are correlations between the choice of Airbnb and personal value profiles. Three research questions were developed according to the research purposes: (1) What motivations attract young Chinese travellers to choose Airbnb? (2) What are the segments of young Chinese travellers regarding the motivations of using Airbnb? (3) What are the value profiles of young Chinese Airbnb users?
This study adopted a similar quantitative research method to the previous study of Guttentag et al. An online survey method was adopted concerning the research nature and the difficulties of data collection during the COVID-19 quarantine period. The questionnaire was designed by two online survey service websites: Qualtrics and Wenjuanxing. The survey link was posted on various social media platforms, which resulted in 296 responses. The results indicate fourteen out of seventeen motivators from Guttentag et al.'s study affecting the use of young Chinese tourists which were grouped into four factors - Sharing economy ethos and local authenticity, home benefits, novelty and function & interaction. The respondents were grouped into four segments – Easy-going consumers, Non-collaborative consumers, Egocentric consumers and Captious consumers – based on the levels of agreement with motivations. Additionally, two personal value factors affected young Chinese tourists' use of Airbnb – contradiction and adaptation. Numerous practical and theoretical implications were discussed. Areas for current limitations and recommendations for future research were also described