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Effects of ocean acidification on the larval settlement and metamorphosis of marine invertebrates
No full textFuture Ocean acidification (OA) has the potential to negatively affect marine ecosystems and the organisms they support, with the early life-history stages particularly sensitive to reduced seawater pH and carbonate saturation states. Most marine organisms reproduce through an indirect lifecycle, which includes a free-swimming larval stage. In benthic or sessile taxa, the lifecycle is marked by the larval settlement and metamorphosis processes. Here, at the end of the free-living (generally planktonic) stage, larvae selectively search for a preferred settlement substrate for attachment, with metamorphosis occurring before or after it. Larval settlement and metamorphosis are arguably the most important processes in the life cycle of marine invertebrates, since they determine and optimize the final location of the organisms. Altered larval settlement rates will therefore influence the ecology, abundances and distributions of future coastal communities.
The aim of this thesis was to investigate whether OA could affect the larval settlement success of marine invertebrates, and whether these impacts would be mediated through direct, indirect or carry-over mechanisms. Three key New Zealand coastal marine invertebrates were used as model organisms: the sea urchin Evechinus chloroticus, the black-footed abalone (Haliotis iris) or pāua and the serpulid polychaete Galeolaria hystrix.
Direct effects of OA occur through altered larval behaviour or physiology at the time of settlement in such a way that settlement success is affected. Direct effects of OA were investigated in E. chloroticus and H. iris, by exposing competent larvae to reduced seawater pH during settlement (Chapter 2). Settlement success in E. chloroticus was unaffected under a range of pH treatments (pHT 7.0 to ambient). Similarly, no direct effects were observed in the abalone H. iris when left to settle in reduced seawater pHT (7.65).
Exposure to OA could affect the settlement substrates or cues in such a way that it could indirectly alter the settlement success. Indirect effects of OA were tested in E. chloroticus, H. iris and G. hystrix (Chapters 2, 3 and 4, respectively). Settlement success in E. chloroticus was unaffected in presence of crustose coralline algae (CCA) pre-conditioned under reduced seawater pHT 7.7 for 28 days. Similarly, settlement success in H. iris was unaffected when presented with CCA-covered settlement tiles incubated at reduced seawater pHT 7.65 for 171 days. However, settlement success in competent G. hystrix was altered in presence of marine biofilms incubated in a range of six pH treatments (pHT 7.0 to ambient) for 7, 10 and 14 months, although the mechanisms behind it could not be discerned. This study revealed clear shifts in the marine biofilm community composition, at both eukaryote and prokaryote levels.
Carry-over effects due to exposure to OA during larval life were investigated and found in H. iris (Chapter 3). Larvae reared under reduced pHT (7,80) showed lower settlement success than their counterparts reared under ambient levels of pH.
Given the importance of marine invertebrates in coastal ecosystems, it is important to understand how ocean acidification, alone or in combination with other stressors, could affect early-life stages of coastal species. This will help us predict the effects on settlement and recruitment rates of coastal marine invertebrates, which in turn regulate their abundances and distributions in coastal environments. This could cause important changes on the population biology and life-histories of keystone species, which could have negative top-down or bottom- up effects on the fragile balance of coastal ecosystems. Similarly, altered settlement rates of commercially important species could impact the recruitment success and therefore the economic revenue and production outcomes the aquaculture industry and wild fisheries rely on.
Overall, this thesis contributes to a better understanding of the potential effects of OA on the larval settlement of marine invertebrates. Furthermore, the main observations of this thesis support the notion that the effects of OA will most likely be taxa-specific and be associated with the settlement selectivity in a particular species or group
Thermoreversible hydrogels based on PEO stars
No full textThe aim of the project is to develop a range of hydrogels made from biocompatible monomers which could be used in various biomedical applications. The particular interest is on star-shaped block copolymers which consist of a hydrophilic core and a thermoresponsive arm. When heated above its LCST the thermoresponsive block aggregates and forms a physical cross-linking which is reversible upon cooling. In particular, the project will be focussing on gels that might be useful in tissue printing. In these methods, cells are deposited in a gel or gel precursor, the gel cross-linked, usually by UV, and placed in a growth media. Thermoresponsive gels seem ideally suited for this, as the lack of permanent cross-links might allow for easier cell growth and UV light can damage cells. In this work, commercial PEO stars will be used as the hydrophilic core and various thermoresponsive polymers were grown from it by ATRP
Titles and their entitlements
No full textThe concern is with titles, and what they are entitled to do and be. The chapters that make up the thesis are about categories of titles, and so the continuity between chapters is one of theme. Chapter One proposes a point of departure for the descriptive title, namely, reference. What follows is discussion of two types of descriptive title, the economy of description, and some of the difficulties artists have faced in giving titles to their creations. Chapter Two discusses six senses of description, and Chapter Three draws out one of the former six for further consideration. The concluding chapter is again about categories, but this time the categories are ones of medium, words and images
Climate change and behaviour change : empowering youth action through narrative
No full textDVD available with hardcopy of thesis
On title frame of DVD: Carving the future : "Inspirational young New Zealanders leading change" : a film / by Guy Ryan & Nick Holmes.
"www.carvingthefuture.com"--Title frame of DVD.
"January 2010"
Colour recording system for DVD: PAL.This thesis is a review of the literature spanning multiple disciplines to provide an overview of climate change science in the global and New Zealand context, its implications, and a context for action amongst young New Zealanders. On the balance of scientific evidence, human activity is affecting the Earth's climate to the extent that it may have catastrophic consequences for development. Addressing the climate change problem requires unprecedented mitigation and adaptation, which many now argue is the defining challenge of our generation. By exploring social and behavioural change theory, and the use of narrative as a tool for empowering change, this thesis provides insights that could aid the transition towards low-carbon communities.
Generally, solutions reside in a fundamental shift away from the consumption of fossil fuels towards clean renewable energy and more sustainable management of the Earth's resources. This thesis notes considerable barriers to social and behavioural change and that strategic use of narrative provides insight to help overcome them. At the grassroots community level, the use of narrative is emerging as an effective tool to empower individual and collective action towards resilient, low-carbon communities. When narrative is designed to communicate desirable behaviour through relevant, local personal stories to defined target audiences, it may be a powerful tool for change.
This thesis concludes that with a deepened understanding of the problems and solutions surrounding climate change, paired with insights to empower behaviour change through narrative, communicators could aid the transition towards resilient low-carbon communities. If given the required urgency, it may still be possible to avoid some of the most catastrophic consequences associated with climate change
The Use of Regional Accent in Audio Health Communications
No full textCancer is a large and complex family of diseases with a variety of causes and risk factors. The health communication strategy needed to combat cancer may also need to be a large and complex family of communications. Podcasts are an easily made, readily accessible form of audio communication. However, little research has been done about the use of podcasts for health communications. Drawing on the body of literature that supports the efficacy of tailored and targeted health communications, this project looks at the use of audio cancer prevention communications tailored with three regional accents, the American Midwestern accent, the Southern Texan accent, or the Tejano (Texan Mexican American) accent, focusing on a cancer prevention message in two cohorts, Americans (excluding Texans) and Texans.
After listening to any of the three audio communications, both cohorts had a strong comprehension of the message and intended to exercise more. The American population reported liking the Southern-accented narrator less and viewing the message as less valid compared to the other narrators, but this did not impact either comprehension or intention to exercise. The Texan population had no significant difference in response to any of the three accents. However, in both the Texan and American population, there was a difference in the response to accents between men and women. Additionally, Americans who had been affected by cancer rated the only Midwestern-accented message higher in validity than those who hadn’t been affected, while Texans who had been affected by cancer rated only the Southern-accented message as higher in validity than those who hadn’t.
This study found that audio health messages were well comprehended by listeners regardless of regional accent. It also found that regional accent may interact with other axes of identification, such as gender or association with disease, to create a significant increase in perception of validity of the health communication. Given the increasing popularity of podcasts and the need for health communications targeted towards specific populations, this study is an important addition to the health communications field, with implications for future research
Investigating Rāhui as a Customary Fisheries Management Tool
No full textMarine fisheries resources sustain the social and cultural wellbeing of communities. Almost one third of the world’s fisheries are overfished. The decline or collapse of a fishery not only has significant biological effects but can also have localised socioeconomic effects on communities that rely on fisheries resources for food, income and wellbeing. There has been a move away from single species management towards an ecosystem-based management (EBM) approach which considers the ecology of the target species, and takes into account socioeconomic factors. Local community management can be seen as an extension of ecosystem-based management, where the ecosystem includes the fishers who use the resource. The traditional knowledge of local communities is important in informing the management of fisheries as it accumulates over successive generations and incorporates social, environmental and cultural aspects.
In Aotearoa New Zealand, traditional knowledge is referred to as mātauranga Māori and is a knowledge system that shapes Māori identity and centralises a Māori worldview. Mātauranga Māori informs tikanga which encompasses a set of physical and spiritual principles on which to act. Māori fishing rights were guaranteed under Article II of the Treaty of Waitangi which guaranteed rangatiratanga or authority over the use and management of fisheries resources. Restrictions or temporary closures on a fishery are referred to as rāhui, a method in accordance with tikanga that provides for kaitiakitanga (environmental guardianship) at a local scale to protect resources and restore balance back to the ecosystem. The practice of rāhui has been translated into a legal framework under Section 186A and 186B of the Fisheries Act 1996 which provides for a two-year temporary closure on a fishery.
The aim of this research was to understand whether traditional (referred to as voluntary) rāhui or legal rāhui provide for rangatiratanga, and the right to exercise kaitiakitanga. This research also aimed to identify a management tool that recognised rangatiratanga, aligned with the principles of rāhui and was recognised within a legal framework and was therefore protected by law.
Methodologically, this research was guided by Kaupapa Māori theory and utilised the qualitative methods of case study, wānanga, and semi-structured interviews with tangata tiaki/kaitiaki. One case study was situated in Whareponga on the East Cape of the North Island and investigated a voluntary rāhui. The other case study was situated in the East Otago Taiāpure (EOT) in the South Island and investigated a legal rāhui under Section 186B of the Fisheries Act 1996.
This thesis found that the voluntary rāhui in Whareponga was adaptable and provided for rangatiratanga but was not protected by the law. The legal rāhui in the EOT, on the other hand, although protected by law, was inflexible and did not provide for full rangatiratanga. However, proposed changes to fishery regulations in the EOT will provide for aspects of rangatiratanga and allow managers to exercise kaitiakitanga with the recognition of core cultural environmental management principles. These regulations will allow for a fully customary fishery that is informed by mātauranga, in accordance with tikanga and protected by law
"I'm lucky to have a house." A critique of current and past housing policy and practice, and the effects on a group of Invercargill residents and housing providers.
No full textHousing is not just about the building. It is a home, where people create their identity, live out their relationships, their plans and their social and cultural obligations (Easthope, 2004:135; Clapham, 2002:48). It is subject to several international human rights obligations for which the New Zealand government is accountable.
It is at the same time a political-economic unit; a vehicle for financial investment, a market-based tradeable commodity. This dualism is a factor in New Zealand’s current mix of social and market-based housing (Bierre, Howden-Chapman and Signal (2008:21).
This study explores how various needs are met by the existing housing mix, which needs are left unmet, and how this impacts on people’s lives.
A constructivist, ethnographic methodology enables the development of a comparison analysis of housing from multiple points of view: Invercargill residents and housing providers were interviewed using a semi-structured format.
The result is a context-rich exploration of Invercargill’s existing capacity to adequately house its population in homes that are secure, warm and safe.
The study concludes that whole groups of Invercargill people are excluded from adequate housing, and have great difficulty having their voices heard.
What is suggested is a whole-of-society housing strategy that meets New Zealand’s human rights obligations. The strategy should link to policy and programmes at community-level, and be based on participation of residents and providers at all levels and stages. the abstract of your thesi
The Effects of Proportional Representation on Election Lawmaking in Aotearoa New Zealand
No full textIt is widely recognized that most politicians are self-interested and desire election rules beneficial to their reelection. Although partisanship in electoral system reform is well-understood, the factors that encourage or constrain partisan manipulation of the other democratic “rules of the game”—including election administration, franchise laws, campaign finance, boundary drawing, and electoral governance—has received little scholarly attention to date. Aotearoa New Zealand remains the only established democracy to switch from a non-proportional to a proportional electoral system and thus presents a natural experiment to test the effects of electoral system change on the politics of election lawmaking. Using a longitudinal comparative case study analysis, this thesis examines partisan and demobilizing election reforms passed between 1970 and 1993 under first-past-the-post and between 1997 and 2018 under mixed-member proportional representation (MMP). Although partisan election reforms have not diminished under MMP, demobilizing reforms have become less common. Regression analysis uncovers evidence that partisan election lawmaking is more likely when the effective number of parties in parliament is lower, when non-voters have more leverage, and when reforms are pursued that diminish electoral participation
MUSIC for Medical Students: Confirming the Reliability and Validity of A Multi-Factorial Measure of Academic Motivation for Medical Education
No full textConstruct: The MUSIC® Inventory measures the construct of academic motivation across five factors: empowerment, usefulness, success, interest, and caring. The factors are defined in terms of the degree the student perceives that they have control over their environment, that the coursework is useful to their future, that they can succeed in the course, that the course and instructional methods are interesting, and that the teacher cares about their wellbeing and their success respectively.
Background: A valid measure of medical students’ academic motivation would provide medical teachers with a method for evaluating the motivational aspect of their course, and provide focus for changes in teaching and learning to improve medical student engagement. While the MUSIC® Inventory structure has been validated in the tertiary setting and with several professional programs, it has not been validated with medical students. The aim of this study was to use both classical test theory and Rasch modelling to assess the reliability and confirm the structure of the five-factor model of the MUSIC® Inventory with medical students.
Approach: 152 medical students completed the 26-item inventory. Descriptive statistics, internal consistency, correlations between factors, confirmatory factor analysis, and Rasch analysis using the rating scale model were performed to determine reliability and validity.
Findings: The five factors showed good internal consistency (Cronbach’s alpha 0.87 – 0.92). Correlations between factors were moderate to high (r=.38 – .89). Confirmatory factor analysis highlighted inconsistencies in factor loadings of three of the items hypothesized to measure interest. Rasch analysis using the rating scale model showed that all items for each factor had good item fit (0.65 – 1.37). Person separation (2.28 – 2.85) and reliability (.84 –.91) scores indicated that the scales were able to differentiate different levels of respondents. Item separation (2.25 – 6.97) and reliability scores (.83 –.98) indicated that the items of the scales were being differentiated by the respondents.
Conclusions: Rasch analysis indicates that the five factors of academic motivation measured by the MUSIC® Inventory account for the response patterns in data from medical students. However, while the factors of empowerment, usefulness, success, and caring showed expected reliability and validity using classical analysis, three of the interest items cross-loaded on to the usefulness factor. Possible reasons may include ambiguity of language for the items or medical students' conception of usefulness and interest. Future research will explore medical students' understanding of the language used to measure these factors in further detail.Peer Reviewe
Life-Prolonging Medical Care and Religiosity at the End of Life.
No full textStudies from around the world indicate that highly religious people request and receive more aggressive end-of-life medical care than their less religious counterparts. Research suggests that patients who express strong religiosity are less likely to engage in advanced care planning and more likely to desire and receive life-prolonging medical care such as resuscitation and mechanical ventilation.
Why would religious people be more likely to request and receive extraordinary end-of-life medical intervention than those who are less religious? The underlying mechanisms are currently unknown and seem to contradict a commonly held assumption that increased religiosity would ease dying.
The purpose of this study is to explore and understand the connection between an individual’s religiosity and his or her end-of-life medical decisions. End-of-life decisions are, at once, intensely personal and also a matter of public interest. Individuals want the option and wisdom to die well. Policy-makers and administrators have noticed the exponential increase in spending associated with end-of-life care. Physicians report concern that extraordinary end-of-life intervention may be harming more patients more than it helps. The current research can inform both religious and medical communities about who receives extraordinary end-of-life medical care and why.
This study used a qualitative approach that combined a literature review with in-depth interviews (n=14). The interview questions evaluated six hypotheses that have been proposed to explain the connection between religiosity and an increased likelihood of aggressive end-of-life medical care: suffering, sanctity of life, God’s sovereignty, miracles, afterlife, and social support. Interviews suggest that religious and nonreligious people hold different beliefs and opinions on theological topics, but these beliefs and opinions have little direct effect on a preference for life-prolonging medical care. In other words, the observed connection between religious patients and intensive end-of-life medical care may have less to do with the theological beliefs of the patient and more to do with the social support that religious people experience. Findings suggest that theological-based mechanisms may be more active in end-of-life situations involving younger patients who are perceived to have been thwarted in completing a natural course of aging