588 results for Scholarly text, 2016

  • Devils & dust

    Brechin-Smith, David (2016)

    Masters thesis
    Victoria University of Wellington

    A screenplay.

    View record details
  • The impact of intellectual capital on firm performance among R&D engaging firms

    Ariff, Arifatul Husna Mohd (2016)

    Doctoral thesis
    Victoria University of Wellington

    This thesis investigates the impact of aggregate intellectual capital (IC), and its elements, human capital, structural capital and tangible capital, on firm performance. In addition, the study also examines the impact of past research and development (R&D) activity on the relationship between IC and firm performance. The study employs the original and modified Value Added Intellectual Coefficient (VAICTM) models to measure IC. Firm performance is measured from two different perspectives: market and financial. The study uses a sample of 1,328 firm-year observations drawn from multinational firms which engaged in R&D activity over the period 2006-2013 and were listed on the U.S. stock exchanges. Using ordinary least squares regression, the study confirms that aggregate IC has a significant positive impact on both the market and financial performance of firms. Human capital has no significant impact on market performance, but it has a significant positive impact on financial performance. Structural capital and tangible capital each have a significant positive influence on both the market and financial performance of firms. In addition, the study finds that past R&D activity has a significant positive impact on the relationship between aggregate IC and both market and financial performance. However, the study finds mixed results for the role of past R&D activity on the relationship between the IC elements and firm performance. The study contributes to the existing literature by providing empirical evidence on the impact of IC on firm performance among multinational R&D engaging firms. The study also adds to the literature by providing empirical evidence on the role of R&D activity in influencing the relationship between IC and firm performance and thus enhances the current understanding of the role of IC and R&D. In addition, the study contributes to the methodology by proposing a modification to the original VAIC model and empirically tests the resulting modified VAIC model. The study thus provides empirical evidence of the impact of IC on the market performance and financial performance of firms. This evidence should be useful to firms in developing their IC and R&D policies, to users of financial statements in evaluating the benefits from IC among R&D engaging firms, and also to accounting standard setters in identifying the information on IC that should be included in financial reports.

    View record details
  • Milk price cuts reflect the reality of sweeping changes in global dairy market

    Lockhart, J; Donaghy, DJ; Gow, H (2016-05-12)

    Scholarly text
    Massey University

    Published

    View record details
  • Murray Goulburn and Fonterra are playing chicken with dairy farmers

    Lockhart, J; Donaghy, DJ; Gow, H (2016-05-23)

    Scholarly text
    Massey University

    Published

    View record details
  • Guardians of the Park: Intensifying development along the edge of urban green space within Christchurch.

    Willis, James (2016)

    Masters thesis
    Victoria University of Wellington

    On February 22 2011 a 6.3 magnitude earthquake struck the Canterbury region causing widespread damage to both Christchurch city and surrounding areas. The quake devastated the city taking lives and causing significant damage to building and land infrastructure both in the inner city and the eastern suburbs. Whilst there has been significant investment and re-development within the central city much of the eastern areas have been neglected. Over 7000 homes have been demolished in the eastern residential red zone leaving a large swathe of land which stretches from the edge of the city centre to New Brighton. With such significant infrastructure being lost much of the city has shifted west with further developments being planned on the outskirts of the city adding to the existing problem of planned urban sprawl that had begun long before 2011. This thesis explores opinions for the eastern residential red zone, building upon existing proposals to turn the area into an urban forest – letting the area return to nature and transforming it into a place where the city celebrates the environment rather than fighting against it. What happens on the edge of this emerging green space will be key to how the eastern suburbs begin to recover post-earthquake and also how successfully this space is integrated into a city with a changing identity. At the urban scale, the proposal explores opinions for the edge of this developing green space through the development of 6 nodes or ‘Guardians of the Park’. These nodes draw from Peter Calthorpe’s theory of the pedestrian pocket, creating a series of interconnected areas of intensification that stretch from the edge of the CBD following the Avon River to New Brighton. Each node is walking distance from significant transport infrastructure and intended to reinforce the city’s connection with the green space through a form of mixed use development with housing, light retail and a number of recreational facilities. Through these nodes the design case study explores the potential for architecture on the edge of this green corridor to be increased in density and stimulate more significant redevelopment in the east though providing access to this new amenity. It explores access to and connection with both open space and recreational activity incorporating theories of increased density housing development and public transport.

    View record details
  • Nanoparticle Charge and Shape Measurements using Tuneable Resistive Pulse Sensing

    Eldridge, James (2016)

    Doctoral thesis
    Victoria University of Wellington

    Accurate characterisation of micro- and nanoparticles is of key importance in a variety of scientific fields from colloidal chemistry to medicine. Tuneable resistive pulse sensing (TRPS) has been shown to be effective in determining the size and concentration of nanoparticles in solution. Detection is achieved using the Coulter principle, in which each particle passing through a pore in an insulating membrane generates a resistive pulse in the ionic current passing through the pore. The distinctive feature of TRPS relative to other RPS systems is that the membrane material is thermoplastic polyurethane, which can be actuated on macroscopic scales in order to tune the pore geometry. In this thesis we attempt to extend existing TRPS techniques to enable the characterisation of nanoparticle charge and shape. For the prediction of resistive pulses produced in a conical pore we characterise the electrolyte solutions, pore geometry and pore zeta-potential and use known volume calibration particles. The first major investigation used TRPS to quantitatively measure the zeta-potential of carboxylate polystyrene particles in solution. We find that zeta-potential measurements made using pulse full width half maximum data are more reproducible than those from pulse rate data. We show that particle zeta-potentials produced using TRPS are consistent with literature and those measured using dynamic light scattering techniques. The next major task was investigating the relationship between pulse shape and particle shape. TRPS was used to compare PEGylated gold nanorods with spherical carboxylate polystyrene particles. We determine common levels of variation across the metrics of pulse magnitude, duration and pulse asymmetry. The rise and fall gradients of resistive pulses may enable differentiation of spherical and non-spherical particles. Finally, using the metrics and techniques developed during charge and shape investigations, TRPS was applied to Rattus rattus red blood cells, Shewanella marintestina bacteria and bacterially-produced polyhydroxyalkanoate particles. We find that TRPS is capable of producing accurate size distributions of all these particle sets, even though they represent nonspherical or highly disperse particle sets. TRPS produces particle volume measurements that are consistent with either literature values or electron microscopy measurements of the dominant species of these particle sets. We also find some evidence that TRPS is able to differentiate between spherical and non-spherical particles using pulse rise and fall gradients in Shewanella and Rattus rattus red blood cells. We expect TRPS to continue to find application in quantitative measurements across a variety of particles and applications in the future.

    View record details
  • Geographic Information Systems and Geospatial Data in New Zealand and Australian Academic Libraries

    Smith, Michael (2016)

    Scholarly text
    Victoria University of Wellington

    Research problem: Geographic Information Systems (GIS) offer a means of gathering, viewing, managing and analysing spatial information. Technological changes are making GIS more widely accessible to researchers in many disciplines. Academic libraries have responded to growing demand by implementing GIS support services. Little research has been undertaken regarding GIS services provided by academic libraries in New Zealand and Australia. This research project aimed to discover the extent and nature of GIS services offered and librarians’ perceptions regarding factors influencing implementation of library GIS services. Methodology: A quantitative study was carried out of tertiary academic libraries in New Zealand and Australia. 78 academic libraries or library networks were invited to complete an online questionnaire regarding GIS services in their library and wider institution. Results: 17 libraries (22%) completed the survey. 59% of surveyed academic libraries offer one or more GIS services. These are primarily university libraries at larger institutions. Non-university libraries offer few GIS services. Services relating to geospatial data management and information literacy are the most frequently offered. The implementation of new GIS services is driven primarily by stakeholder demand, while lack of demand, library staff knowledge of GIS and funding are the main barriers to implementation of new GIS services. Implications: Academic libraries in the region need to be aware of the growth of GIS in academia and responsive to the needs of GIS users by monitoring demand for GIS services and introducing tailored, relevant and sustainable GIS services.

    View record details
  • Intersections between Pacific leadership and international development

    Fernandez, Sean (2016)

    Doctoral thesis
    Victoria University of Wellington

    As part of the Millennium Development Goals, the United Nations has a long-held commitment to universal primary education for all children. Aid donors in wealthy nations have taken up this call and international development programmes have subsequently been set up in recipient countries where education is not available to everyone. Despite this, an estimated 1.6 million school-aged children in the Pacific region do not currently have access to formal primary schooling. As the timeframe for achieving the Millennium Development Goals draws to a close it is now clear that this aspiration will not be realised in many parts of the Pacific and a generation of children will grow up without a primary education. This raises questions about the design, delivery and management of international aid programmes in the education sector that are often led by people who are not members of the Pacific communities that they seek to assist. This research explores the frustrations felt by recipients of education development programmes in two nations in the Pacific, Tonga and Fiji focusing on the relationship between international development in the Pacific and leadership styles and cultures in the education sector. A key problem that was articulated by aid recipients is that international aid relationships in the Pacific continue to be dominated by the discourses and priorities of donor nations and important opportunities to develop grassroots and local forms of leadership that respond directly and knowledgeably to the rapidly changing needs of Pacific communities have yet to be fully realised. At the same time, new forms of Pacific leadership are emerging as global economies increasingly affect the lives of people living in remote communities and there is a need to respond to these changes because they have a direct impact on schooling for children who live in those areas. Donor nations have not contributed significantly to local leadership development in the education domain and this is an ongoing source of tension for many people because there are so few formally trained indigenous leaders in the education field. The lack of local leaders in this area has an impact of the level of buy-in that Pacific communities give to educational aid projects. This thesis argues that if donor nations are serious about providing universal primary education, leadership development needs to be supported more comprehensively.

    View record details
  • Exploring opportunities for developing intercultural competence through intercultural communicative language teaching (ICLT): A case study in a Chinese as a foreign language classroom in a New Zealand high school

    Kennedy, Juliet Vicary (2016)

    Masters thesis
    Victoria University of Wellington

    This qualitative case study explores naturally arising opportunities for developing intercultural competence through intercultural communicative language teaching (ICLT) in a New Zealand high school Chinese as a foreign language (CFL) classroom. Although developing intercultural competence is a goal of many school curriculums, teacher awareness and implementation of effective intercultural pedagogies is not yet wellestablished. Exploring the naturally arising occurrences of intercultural teaching practices and behaviours in one classroom with no formal knowledge of ICLT provides evidence of how culture may be currently understood and approached in comparative settings. Existing views on culture provide a starting point for further developing ICLT. Data collection methods included classroom observations, stimulated recall, unstructured and semi-structured interviews, and written reflections. One teacher and three students from an intermediate level CFL class participated in the study from June to September 2015. The findings show that while some intercultural pedagogies and behaviours occurred naturally, without an explicit focus on developing intercultural competence students are unlikely to develop the skills, attitudes, and traits which make up intercultural competence in the language classroom. This study suggests that the current cultural activities in class could be transformed into opportunities for developing intercultural competence by adding a regular comparative, connective, and reflective dimension, incorporating the students’ linguistic and cultural experiences. The results of this study illustrate the necessity of expanding teacher awareness and skills in practising ICLT to promote the development of intercultural competence and to increase students’ interest in learning languages in New Zealand.

    View record details
  • Achieving Accountability: Prosecuting the Denial of Humanitarian Assistance in Non-International Armed Conflict

    Farquhar, Harriet (2016)

    Scholarly text
    Victoria University of Wellington

    Over the past decade, the number of people in need of humanitarian assistance as a result of armed conflict has grown to unprecedented levels. The rapid and effective provision of such assistance constitutes one of the greatest challenges faced by the international community in protecting civilians and other protected persons in times of conflict. While international humanitarian law imposes extensive obligations on the parties to a conflict to grant access to humanitarian actors and facilitate the provision of relief assistance, these rules are routinely violated. This results in significant and prolonged suffering of civilian populations. If the law governing humanitarian assistance is to be better respected, those who act unlawfully must be held accountable. One of the most effective mechanisms for ensuring such accountability is prosecution of international crimes at the International Criminal Court. In its present form, however, there is no provision in the Rome Statute of the International Criminal Court which provides specifically for the prosecution of the unlawful denial of humanitarian assistance in non-international armed conflict. This paper argues that this leaves a significant gap in the accountability framework, and examines possibilities for reform.

    View record details
  • New Methods for Studying Materials Under Shear with Nuclear Magnetic Resonance

    Brox, Timothy Ian (2016)

    Doctoral thesis
    Victoria University of Wellington

    For over 30 years, nuclear magnetic resonance (NMR) techniques have been used to study materials under shear. Collectively referred to as Rheo-NMR, these methods measure material behaviour due to external stimuli and provide spatially and temporally resolved maps of NMR spectra, intrinsic NMR parameters (e.g. relaxation times) or motion (e.g. diffusion or flow). As a consequence, Rheo-NMR has been established as a complementary technique to conventional rheological measurements. In this thesis, new hardware and experimental methods are presented with the goal of advancing this exciting field through further integration of traditional rheometry techniques with NMR experiments. Three key areas of hardware development have been addressed, including: 1) integrating torque sensing into the Rheo-NMR experiment for simultaneous bulk shear stress measurements, 2) constructing shear devices with geometric parameters closer to those used on commercial rheometers and 3) implementing an advanced drive system which allows for new shear profiles including oscillatory shear. In addition to presenting the design and construction of various prototype instruments, results from validation and proof of concept studies are discussed. This information demonstrates that the hardware operates as expected and establishes an experimental parameter space for these new techniques. Furthermore, these methods have been applied to open questions in various physical systems. This includes exploring the influence of shear geometry curvature on the onset of shear banding in a wormlike micelle surfactant system, observing shear induced structural changes in a lyotropic nonionic surfactant simultaneously via deuterium spectroscopy and bulk viscosity as well as studying interactions of flowing granular materials. The interpretation and implication of these observations are discussed in addition to motivating further studies.

    View record details
  • "I just find it awkward": Girls' negotiations of sexualised pop music media

    Goddard, Sarah (2016)

    Doctoral thesis
    Victoria University of Wellington

    This thesis examines girls’ relationship with and consumption of female pop stars’ music media. It is contextualised within a period of extensive academic and media debate about girls’ engagement with what has been termed the sexualisation of culture. Much of the alarm concerning girls’ premature sexualisation is underpinned by the presumption of girls as passive media consumers who are uniformly influenced by sexually saturated female pop music, particularly its ubiquitous representation of hyper (hetero) sexually desiring femininity. The notion of girls as precociously sexualised by hypersexual female pop music media has gained homogenous status within mainstream media and popular psychology texts. Girls’ pleasurable consumption and negotiation of a sexually laden media landscape is approached in this research as complicated by their contradictory positioning as savvy consumers within the postfeminist girlhood consumer market and simultaneously as victims within mainstream media and academic literature. Grounded in feminist poststructuralist understandings of girls’ subjectivity, the thesis explores the possibilities of self that representations within female pop music media enable and constrain for girls. Furthermore, the thesis explores ways in which girls make sense of these discourses while carefully managing their positioning as consumers. The research upon which this thesis is based has two parts. Part one of the research involved focus groups within which 30 pre-teen girls, identifying as ‘Kiwis’ or ‘New Zealanders’ discussed their engagement with female popular music media. The second part comprises a thematic discursive and semiotic analysis of girls’ self-recorded group video performances to a favourite pop song by a female artist. Discursive analysis of the professional music videos on which girls’ performances were based accompanied analyses of girls’ videos. The thesis contributes to a growing body of critical feminist research which responds to sexualisation claims that underpin hegemonic understandings of contemporary girlhood. The analyses presented in the research challenge moralistic notions of girls as uniformly influenced by pop music media by highlighting their navigation of this media as a contradictory process of appropriation and rejection. This complex negotiation, while seen in previous feminist literature, is uniquely captured within this thesis through the innovative employment of a performance method that extends feminist theorisations which problematise binary assumptions of girls’ engagement with sexualised media. This research identifies girls’ meaning making as a contradictory and plural process and provides novel insights about girls’ negotiation of postfeminist femininities in their own self-making in relation to self. Crucially, the thesis highlights the way in which girls’ navigation of sexualised media can be understood as occurring through both rejection and reproduction of postfeminist femininity ideals. Contextualised in New Zealand, the research extends knowledge about girls’ navigation of sexualised media beyond a US/UK social context. It also advances the small body of New Zealand literature about girls’ media engagement broadly and about the ways they experience sexualised media in particular.

    View record details
  • Exploring the use of ICTs in non-profit sector organisations: supporting the third act

    Priyanga De Silva Senapathy, Nishanie (2016)

    Doctoral thesis
    Victoria University of Wellington

    Life after retirement from full-time work is known as the third act of an individual. In New Zealand the third act has become longer, resulting in an ageing population. An implication of population ageing is the need for increased support and services for older people who live within the community. Non-profit sector organisations primarily cater to those that are either beyond the reach of state services or are unable to afford services offered by the commercial sector. This study is guided by the central research question: how can non-profit sector organisations use ICTs to support service provision for older people living within the community? Using Lamb and Kling’s social actor model, adapted to the context of non-profit sector, the research project explores how ICT use is influenced by factors that are investigated under four key dimensions: affiliations, environment, identities and technology. Employing a case research method, it studies ICT use in four human services non-profit sector organisations. The analysis of the case studies revealed how external influences are enacted within organisations. The study presents a framework which explains post-adoptive use in non-profit sector organisations incorporating external factors, the organisational view and social actor behaviours. The findings suggest that client and funder information requirements influence organisations to select one of four responses to external cues. Organisations adopt either a complementary perspective, a competing perspective, a compatible view or a negotiated view. These organisational information perspectives craft social actor behaviours within non-profit organisations. Further, this study found information challenges associated with maintaining complex client requirements. Mobility of the work force, deficiencies in data capture and limitations of existing client information systems constrain information flow in these organisations. As a result analysis of service utilisation data fails to communicate the actual value created within communities. This study has extended the understanding of ICT use in non-profit human services organisations in New Zealand and contributed to knowledge in the development of the social actor model within specific contexts. The original contribution of this study is the three-tier typology of social actor- information roles. The study presents social actor behaviour associated with a primary entity and an information role. Five main social actor- information roles were identified across three tiers and have been mapped against a spectrum of information behaviours associated with each role. When responding to external cues social actors engage in task related behaviours associated with their information roles. By contributing to ICT use practices, this research presents new perspectives on the components of value in organisational processes. Identifying value adding and value communicating information flows, information loss and informal ICT support roles this study presents a detailed analysis of the factors that enhance and constrain ICT use within human services non-profit sector organisations.

    View record details
  • “But I am still a girl after all”: A Discourse Analysis of Femininities in Popular Japanese Manga Comics

    Nishiyama, Yurika (2016)

    Masters thesis
    Victoria University of Wellington

    Where progression towards gender equality is concerned, Japan lags behind most other developed countries with its culture which heavily values tradition. However, its traditional gender roles may be changing as the birth-rate declines and women take up the increasing opportunities opening up for them in the workplace. Within the contexts of these tensions between traditionalism and change, this study investigated the constructions of femininity in popular Japanese manga, one of the most consumed forms of media in Japan which also enjoys global popularity. As such, this study approached manga as a potentially important resource for identifying the available meanings of being a young Japanese woman in contemporary Japanese society. To date, little research has examined manga, and much of the available literature has used content analysis or focused solely on superheroine characters and the romantic interest. As a point of difference, this research implemented discursive analyses and sought to identify a range of femininities made available to readers in manga. It examined four titles within two genres of manga: the shounen genre targeted to male audiences and the shoujo manga, targeted at a female audience. The research employed a feminist, poststructuralist framework to identify the ways in which constructions of femininity in manga drew on dominant Japanese discourses of femininity as well as more globally produced postfeminist discourses associated with popular culture. The study found that manga overall produced femininities within both traditional and contemporary postfeminist discourses. Analyses also highlighted the limited meanings of femininity made available to young female audiences of shoujo manga through dominant postfeminist, empty representations of ‘empowerment’ whilst also underlining the problematic dominance of sexist portrayals of young women in shounen manga. Further, the storylines of shoujo manga were found to be replete with romantic narratives, prioritising romance and marriage as a means to happiness. These findings may identify the implications of such femininities on how young Japanese women view themselves, and are viewed by others globally.

    View record details
  • Behavioural and Neurochemical Effects of Acute (±) 3,4 methylenedioxymethamphetamine (MDMA) in the Dopamine D1 Receptor Mutant Rat

    Squire, Hanna (2016)

    Doctoral thesis
    Victoria University of Wellington

    Rationale: (±) 3,4-methylenedioxymethamphetamine (MDMA; ‘ecstasy’) is a recreationally abused psychostimulant that leads to detrimental effects on memory performance. MDMA’s acute effects on memory are often attributed to a working memory impairment resulting from compromised serotonin systems. However, recent evidence from non-human animal experimental studies suggests that acute MDMA may impair memory performance through an MDMA-induced increase in dopamine (DA) release, leading to overstimulation of DA D1 receptors. The overstimulation of D1 receptors during acute MDMA exposure is thought to indirectly impair memory by increasing a subject’s susceptibility to proactive interference, leading to a perseverative pattern of responding during memory tasks. Objective: This project investigates the hypothesis that acute MDMA impairs memory performance via overstimulation of D1 receptors. The acute actions of MDMA will be assessed using DA D1 mutant (DAD1-/-) rats which possess a selective down-regulation in functional DA D1 receptors. On the basis that acute MDMA impairs memory function via overstimulation of D1 receptors it is predicted that, compared to control rats, DAD1-/- rats will be protected from the acute memory deficits caused by MDMA. Due to the novelty of the DAD1-/- rat model, prior to the assessment of the acute effects of MDMA on memory performance in these rats, behavioural and neurochemical characterisations will be conducted. Methods: Firstly, a behavioural characterisation was conducted to explore the tendencies of DAD1-/- rats, compared to controls, in a drug free state. Behaviours relevant for motivation and reward, movement, and memory were the focus of the behavioural investigation due to evidence suggesting a role for D1-like receptors in these functions. Secondly, a neurochemical assessment of DAD1-/- and controls rats in response to MDMA (3 mg/kg) was assayed using c-fos expression, a marker for neuronal activity, in several brain regions with known DA innervation. Thirdly, to assess the acute effects of MDMA on memory performance, DAD1-/- and control rats were trained on a spatial working memory T-maze task, delayed non-matching to position (DNMTP), over 25 sessions. Once trained, rats were administered either MDMA (1.5, 2.25 and 3 mg/kg) or saline fifteen minutes prior to testing on DNMTP, with all subjects experiencing all drug doses three time each. In addition, to further investigate the hypothesis that overstimulation of D1 receptors impairs memory performance, the effects of a D1 receptor agonist, SKF 81297 (0.5, 1, 1.5, 3, 4.5 mg/kg) on DNMTP performance were also assessed. Results: The behavioural characterisation revealed that DAD1-/- rats are capable of performing many behaviours relevant for reward processing, movement and memory function. However, DAD1-/- rats were impaired with regard to some reward-related behaviours, such as the acquitision of lever pressing for sugar pellets. The assessment of c-fos expression demonstrated that DAD1-/- rats express less c-fos in the medial prefrontal cortex, striatum and nucleus accumbens compared to control rats following MDMA administration. Lastly, the effects of acute MDMA administration on memory performance were tested. During the third block of MDMA administration, control rats demonstrated decreased accuracy on the DMNTP task at both the 2.25 and 3 mg/kg doses. The decrease in accuracy during MDMA exposure in control rats was driven by an increase in perseverative errors. On the contrary, DAD1-/- rats were not impaired on the DNMTP task following acute MDMA at any of the doses tested. Administration of SKF 81297 did not lead to any systematic changes in performance, but at the 3 mg/kg dose DAD1-/- rats displayed increased accuracy compared to control rats. Conclusions: DAD1-/- rats were protected from an MDMA-induced decrease in accuracy on the DNMTP task compared to control rats. This finding challenges the assumption that MDMA’s acute effects on memory performance are wholly due to serononergic mechanisms. Specifically, the current study provides evidence for the hypothesis that acute MDMA exposure impairs memory performance in rats.

    View record details
  • Blue Cod, Parapercis Colias, Maturity, Fecundity, Sex Change, and Potential Drivers of Sex Ratio in The Marlborough Sounds

    Brandt, Kasper (2016)

    Masters thesis
    Victoria University of Wellington

    Blue cod, Parapercis colias (Pinguipedidae), are widely considered to be the most important recreational finfish species in the South Island. However, blue cod have been declining in abundance in the Marlborough Sounds for many years, and currently, sex ratios are highly male- biased. Blue cod are believed to be a socially structured hermaphroditic species whose populations are prone to local depletion. A potting survey in the Marlborough Sounds was carried out by NIWA in 2013, and along with environmental measurements, 3247 blue cod were measured, weighed, sexed, and stage of sexual maturity was classified macroscopically at sea. Gonads from a subsample of these fish were removed and preserved. In Chapter Two, the preserved gonads were processed histologically and a species-specific histological maturity key was developed. Histological and macroscopic maturity classifications and length-at-maturity estimates were compared. Additionally, estimates of spawning frequency and batch fecundity were made using histological and gravimetric methods. In Chapter Three, possible drivers of sex ratio were investigated using the survey data. Density, large male influence, and environmental factors were considered. In Chapter Four, the feasibility of using digital imaging software to age blue cod otoliths was investigated using the OtolithM application in ImagePro Premier. There was poor agreement between macroscopic and histological maturity classifications (20%, overall). Macroscopic methods overestimated the proportion of mature fish at length in the larger sample, which led to biased length-at-50% maturity (L₅₀) estimates. Macroscopic L₅₀ estimates differed markedly from histology estimates. Using histological data, male L₅₀ was 26 cm TL. Histology indicated that there was no length at which 100% of females were mature. Therefore, a three-parameter capped logistic model was used. Histologically, female L₅₀ was 23.6 cm TL, and the Cap was 0.78, indicating the proportion of mature females reached an asymptote at 0.78. Spawning frequency was 4.6 days, and mean relative batch fecundity was 6.5 hydrated oocytes per gram body weight (SD = 3.3). Hermaphroditism was confirmed for blue cod and was macroscopically identifiable. The analyses in Chapter Three indicated that density had some effect on sex ratio, and large males influenced local sex ratios. Finally, the imaging software could not accurately estimate age compared to an expert reader, and it produced highly variable age estimates. This research found that the macroscopic maturity classifications for blue cod were inaccurate, and revision of the macroscopic key is suggested. The biased estimates of L₅₀ from macroscopic data could lead to biased estimates of spawning stock biomass (SSB). Batch fecundity was markedly lower than the previously reported estimates. The finding of a macroscopically identifiable hermaphroditic stage suggested that ‘hermaphrodite’ should be added as a sex class in the macroscopic key. From the GLM in Chapter Three, in more dense populations, the proportion of males increased. This may have been from changes to male mating strategies, or density may influence the occurrence of primary and secondary males. Finally, areas with males > 45 cm TL had a higher proportion of females, suggesting that large males should be protected in order to help balance sex ratios.

    View record details
  • The impacts of ocean acidification and warming on the Antarctic bivalve, Laternula elliptica

    Bylenga, Christine Heather (2016)

    Doctoral thesis
    Victoria University of Wellington

    Laternula elliptica are large bivalves found in high densities in soft sediments in coastal regions of the Southern Ocean. L. elliptica form an important part of the ecosystem, due to significant sediment stabilisation and deposition. Despite the important role L. elliptica play in their environment, little is known about how projected ocean change will impact future populations of this species. Invertebrate larvae are considerably more sensitive to environmental stressors than juveniles and adults, and increases in mortality and minor reductions in dispersal could significantly reduce future population sizes. In a rapidly changing climate, some of the greatest changes are expected at high latitudes. The greatest rates of warming of surface waters are occurring in the Southern Ocean. Additionally, undersaturation of aragonite due to ocean acidification is expected to affect these waters within decades. Calcifying organisms such as molluscs may be particularly sensitive to reduced pH and saturation states associated with ocean acidification. However, information on larval responses to these stressors in Antarctic species is limited. The larvae of L. elliptica are large and lecithotrophic. Maternally provided energy reserves sustain development until the completion of metamorphosis. While large reserves may support long development times and extended encapsulation, they are finite and cannot be replenished. Any stress during larval development could increase metabolic costs and deplete reserves, preventing metamorphosis. These stressors may also impact the calcification process and shell structures, resulting in weaker larvae at settlement that are more vulnerable to injury. Small reductions in larval survival could limit recruitment and population growth may decline. Various responses to ocean acidification (OA) and warming were studied in the larvae of L. elliptica. Larvae were raised under control pH and temperatures (~8.00 and - 1.7°C, respectively) and conditions representing projections for the Antarctic by the end of the century and 2300 (pH 7.80, 7.65 and -0.5, +0.5 and +1.5°C), both individually and in combination. The effect of these stressors on fertilisation rates, development timing and rates of abnormalities at various life stages were examined. Furthermore, SEM analysis determined the impacts of OA and warming on larval shell growth and morphology. Respiration rates and lipid reserves in developing larvae were also determined. Information on OA and temperature responses in Antarctic larvae is limited, and this is the first study on the effects of these stressors in Antarctic bivalves. Elevated temperatures largely improved development, increased early fertilisation rates, and accelerated development through all larval stages and larvae reached competency 5 d ahead of larvae at the control temperature. This would allow for faster settlement, significantly reducing time spent in more vulnerable development stages. Elevated temperatures also improved calcification in later D-stage larvae increasing shell lengths and reducing pitting and cracking, suggesting these larvae will be in a better condition at settlement. Reduced pH improved fertilisation at control temperatures, but impaired it at elevated temperatures, although overall fertilisation was greater at pH 7.65/0.4°C compared to the control temperatures (60% and 50%, respectively). Developmental delays were observed at reduced pH; however the effect varied between experiments. In the first, developmental delays due to reduced pH were observed at all experimental temperatures and were greatest at 0.4°C, while in the second experiment, delays only occurred at ambient temperature. The delay at ambient temperature was 2 d in both experiments. The delaying effect in the first experiment was mitigated by the overall faster development with elevated temperature. Larvae at pH 7.65/0.4°C reached competency at 22 d compared to 24 d at pH 7.98/-1.6°C. Larvae from the most extreme treatment (pH 7.65 and 0.4°C) still reached the D-larvae stage two days ahead of those at control conditions (pH 7.98 and -1.6°C). This also was the first study to perform a detailed analysis of the effect of pH and temperature on shell size and ultra-structure in Antarctic bivalve larvae. D-larvae from reduced pH treatments had significantly larger shells at elevated temperatures. While light microscopy suggested no significant effect of pH on development, SEM analysis revealed that reduced pH severely impaired the quality of the larval shell at all temperatures. They were more likely to have abnormal larval shapes, as well as malformed hinges and edges. These malformations will carry over into juvenile stages, impairing swimming and feeding capacity, which would reduce settlement success and condition. Additionally, these larvae had lower shell integrity, with high frequencies of pitting and shell damage, including cracking under reduced pH, although elevated temperatures partially ameliorated this effect. Larval shells at reduced pH were weaker, indicating they will be more susceptible to injury and predation. This would flow on to later life-history stages, impairing success in settlement when juveniles must bury in the sediments. This is the second study, and the first for molluscs and Antarctic species, to perform a detailed biochemical analysis of the use of energetic reserves in larvae in response to OA. The larvae of L. elliptica are lecithotrophic, depending on maternally provided energy for development to competency. However, the composition and size of the reserves were unknown. The lipid reserves in the larvae were large, dominated by triacylglycerols and phospholipids. Despite significant depletion of both these lipid classes during development, more than 65% of the original lipid pool remained at the D-larval stage, suggesting significant reserves exist for later metamorphosis. Higher metabolic rates are expected in response to pH and temperature stress and supporting these rates may be energetically demanding. However, larvae did not alter use of any of the lipid classes at elevated temperatures. Increases in oxygen consumption in the larvae at elevated temperature indicated low temperature tolerances in L. elliptica larvae, possibly around -0.5°C. These may place increased energetic demands on later life stages that cannot depend on maternally provided resources. Under OA, the energetic demands of calcification are expected to increase due to the costs of active maintenance of the pH of cellular fluids. However, respiration rates were unaffected by reduced pH and a greater lipid reserve remained in larvae at pH 7.65/-1.7°C compared to all other treatments, suggesting larvae may respond to OA by reducing calcification. Additionally, the impact of reduced pH on biodeposition was assessed in adult L. elliptica. Short term (48 h) exposure to reduced pH (to pH 7.54) did not influence biodeposition rates or the organic composition of faeces and pseudofaeces, although compositional changes may have occurred in the latter due to increased mucous production or altered particle selection. Overall, some resilience to projected climate change conditions was observed in the larvae of L. elliptica. Under future elevated temperatures, larger populations could occur due to improved fertilisation as well as larvae reaching competency sooner with no added energetic costs. However, changes in respiration rates indicate that temperature tolerance thresholds are low. The increased metabolic demands with temperatures above -0.5°C could impair growth beyond the D-larval stage, when they are no longer dependent on maternally provided energetic reserves. Additionally, larvae may be compromised by reduced pH, as shell quality and integrity were significantly impaired. This could significantly influence recruitment and mortality rates in settlement, exposing larvae to crushing fractures in burial or reducing burial capacity. Even with slightly greater larval numbers and faster development, an overall population decline would occur if larvae fail in settlement. This study has shown that the larvae of L. elliptica are highly sensitive to future ocean change conditions, but future studies of later life history stages are needed to confirm the impacts of these changes on the greater population.

    View record details
  • The role of 5-HT1A and 5-HT1B receptors in MDMA self-administration

    Aronsen, Dane (2016)

    Doctoral thesis
    Victoria University of Wellington

    Rationale: 3,4-methylenedioxymethamphetamine (MDMA) is a less efficacious reinforcer than other drugs of abuse. However, following repeated self-administration, responding increases for some animals and efficacy becomes comparable to other drugs of abuse. MDMA-stimulated serotonin (5-HT) release was negatively associated with acquisition of MDMA self-administration, and a neurotoxic 5-HT lesion reduced the latency to acquire self-administration. These findings suggest that MDMA-produced 5-HT release is an important component of self-administration. The receptor mechanisms are not, however, well understood, although it has often been suggested that the mechanism involves 5-HT-mediated inhibition of dopamine. Both 5-HT1A and 5-HT1B receptors are well localised to regulate dopamine release, and both have been implicated in modulating the reinforcing effects of many drugs of abuse. Objectives: The first objective was to establish specific behavioural assays to reflect 5-HT1A and 5-HT1B receptor activation. Then, using the established behavioural assays, the aim was to determine the role of 5-HT1A and 5-HT1B receptors in the acquisition of MDMA self-administration. The impact of substantial MDMA self-administration on 5-HT1A and 5-HT1B receptors was also assessed. Methods: Firstly, dose-effect relationships for the hyperactive response to the 5-HT1A receptor agonist, 8-OH-DPAT (0 – 3.0 mg/kg) and the hyperactive and adipsic response to the 5-HT1B/1A receptor agonist, RU 24969 (0 – 3.0 mg/kg) were determined. Selectivity of these responses was determined by co-administration of the 5-HT1A receptor antagonist, WAY 100635, or the 5-HT1B/1D receptor antagonist, GR 127935. Secondly, a pretreatment regimen of the RU 24969 (2 × 3.0 mg/kg/day, 3 days), which had been suggested to down-regulate 5-HT1B/1A receptors, was administered prior to self-administration testing. The effect of this manipulation on both the acquisition of MDMA self-administration, and the behavioural responses to 5-HT1A and 5-HT1B receptor activation, was measured. A further study measured behavioural responses to 5-HT1A or 5-HT1B receptor agonists prior to self-administration, to determine whether the variability in these responses would predict the variability in the latency to acquisition of MDMA self-administration. Lastly, the effect of substantial MDMA self-administration (350 mg/kg) on dose-response curves for the behavioural effects of 5-HT1A or 5-HT1B receptor activation was assessed. Results: The hyperactive response to the 5-HT1B/1A receptor agonist, RU 24969, was blocked by the 5-HT1A receptor antagonist, WAY 100635, but not the 5-HT1B receptor antagonist, GR127935. Similarly, the hyperactive response to the 5-HT1A receptor agonist, 8-OH-DPAT, was dose-dependently blocked by WAY 100635. GR 127935, but not WAY 100635, blocked the adipsic response to RU 24969. Repeated administration of RU 24969 produced rightward shifts in the dose-response curves for 8-OH-DPAT-produced hyperactivity and RU 24969-produced adipsia, and also greatly facilitated the acquisition of MDMA self-administration. However, there was no correlation between latency to acquire MDMA self-administration and the hyperactive response to 8-OH-DPAT or the adipsic response to RU 24969, and MDMA self-administration failed to alter these behavioural response to activation of 5-HT1A or 5-HT1B receptors. Conclusions: The hyperactive response to 8-OH-DPAT and the adipsic response to RU 24969 reflect activation of 5-HT1A and 5-HT1B receptors, respectively. The variability in acquisition of MDMA self-administration was reduced by a treatment that also down-regulated 5-HT1A and 5-HT1B receptors, however there was no further indication that these receptors play a critical role in the self-administration of MDMA. Instead, it seems likely that other 5-HT receptors have a greater impact on MDMA self-administration.

    View record details
  • The effect of MDMA self-administration on MDMA-produced hyperactivity and c-fos expression

    Bukholt, Natasha (2016)

    Masters thesis
    Victoria University of Wellington

    Background: MDMA preferentially releases serotonin (5HT) but following repeated exposure there is a decrease in this MDMA-produced effect. At the same time, some studies suggest an increase in MDMA-produced dopamine (DA) release following repeated exposure. The sensitised DA response is often accompanied by sensitisation of MDMA-produced locomotor activity. Because DAergic mechanisms have been implicated in the positively reinforcing properties of MDMA, these neuroadaptations might be relevant to MDMA self-administration. Objectives: The main objective of this study was to determine whether MDMA self-administration and non-contingent MDMA exposure differentially affected the development of sensitisation to MDMA-produced hyperactivity. Additionally, the relationship between MDMA-produced hyperactivity and changes in c-fos expression in DA terminal regions was determined. Methods: Triads of rats were designated ‘master’, ‘yoked MDMA’, or ‘yoked saline’. Lever press responding by the master rat resulted in an intravenous infusion of MDMA for both the master rat and the yoked MDMA rat, as well as an equal infusion of vehicle for the yoked control rat. Daily tests continued until a total of 350 mg/kg MDMA had been self-administered. Three days following the last self-administration session, forward and vertical locomotion produced by MDMA (5.0 mg/kg, i.p) were measured during a 2 hr test. Rats were sacrificed immediately following the behavioural test, and c-fos immunohistochemistry was measured. Results: Repeated MDMA exposure resulted in sensitised forward and vertical locomotor activity. Sensitisation of the increase in forward locomotion was produced only in rats that self-administered MDMA; non-contingent MDMA administration failed to sensitise this behavioural response. In contrast, sensitisation to MDMA-produced vertical activity was produced following both contingent and non-contingent MDMA exposure. C-fos expression was reduced in ventrolateral, and ventromedial areas of the dorsal striatum, as well as the infralimbic cortex, after MDMA exposure, regardless of whether the exposure was via self-administration or yoked administration. A selective decrease in c-fos expression in the nucleus accumbens (NAc) core and the cingulate cortex was produced by MDMA self-administration. There was a negative correlation between MDMA-produced forward locomotor activity and MDMA-produced c-fos expression in the NAc core, cingulate cortex and infralimbic cortex. A negative correlation between rearing activity and MDMA-produced c-fos expression in the NAc core, NAc shell, cingulate cortex, and infralimbic cortex was also found. Conclusions: These data provide evidence of behavioural sensitisation as a result of repeated MDMA exposure. Furthermore, MDMA-produced behavioural sensitisation was associated with a decrease in c-fos expression that was evident in the NAc and prefrontal cortex. Finally, region-specific changes in c-fos expression suggest an important role of neuroadaptations in the NAc core and the infralimbic cortex as a consequence of MDMA self-administration.

    View record details
  • Application of the precautionary principle during consenting processes in New Zealand: Addressing past errors, obtaining a normative fix and developing a structured and operationalised approach

    Scott, Dale (2016)

    Masters thesis
    Victoria University of Wellington

    The precautionary principle is increasingly being adopted as a legal risk management tool in international environmental law and regulation, especially in the marine context. In fact, over the last 35 years it has been included, often as a central feature, in the vast majority of international law instruments relating to protection and management of the environment. This rise to prominence is largely driven by widespread recognition that the ability of environmental law to successfully avert long term and significant harm is very much contingent on the successful implementation and application of the precautionary principle (specifically, the decision-making and planning measures it advocates). Owing to the above, it is unsurprising that like many other countries New Zealand has incorporated the precautionary principle expressly and implicitly into domestic law and policy over the last 25 years. The most recent and arguably most notable instance of the incorporation of the precautionary principle in New Zealand law is in the Exclusive Economic Zone and Continental Shelf (Environmental Effects) Act 2012 (“EEZ Act”). Indeed, for reasons explained in this paper, the success of the EEZ Act will in large part depend on the successful application of the precautionary principle contained in the Act. Unfortunately, New Zealand’s incorporation and application of the precautionary principle to date has been problematic, with confusion and a variety of approaches taken to its core concepts, and arguably outright misapplication of it. For this reason, this paper seeks to take comprehensive stock of the precautionary principle, first to identify what is the likely cause of such confusion and misapplication, and second, to provide a foundational understanding to assist policy makers and the courts with the task of operationalising and applying it during legislative consenting processes. In doing so, this paper focuses on its operation in the marine setting, with a view to assisting with its interpretation and application under the EEZ Act. It argues that in order to secure consistent and proper application of the precautionary principle, significant work needs to be done to clarify definitional ambiguities embedded within the principle. It then argues that further work needs to be done to properly operationalise the New Zealand formulations of the precautionary principle (i.e. unpack the substantive content of the principle and pin down what such content requires of decision-makers in practice) so they can be consistently and correctly applied under New Zealand’s environmental risk management regimes.

    View record details