429 results for Undergraduate

  • Assessment of New Zealand's Forest Codes of Practice for Erosion and Sediment Control

    Pendly, Melissa Lin (2012)

    Undergraduate thesis
    University of Canterbury Library

    New Zealand’s forest industry operates under several codes of practice for erosion and sediment control. Inconsistency between regional forestry regulations led industry to lobby for the Proposed National Environmental Standard for Plantation Forestry (PNESPF). A national code of practice may also need to be introduced to give effect to the PNESPF. This dissertation focuses on what type of code of practice should be adopted, and under what conditions. The conditions required for a code of practice to succeed in protecting the environment were identified. The ‘external’ social and legal conditions were identified through analysis of three case studies from the international primary sector, whilst the ‘internal’ conditions relating to the development, content and implementation of a code of practice were identified through review of literature. These ideal internal conditions formed the basis of the criteria used to assess New Zealand's codes. Six of New Zealand’s forest codes of practice were classified by their type, the motivation for a corporation to comply with them, and enforcing agency. The internal conditions of these codes were then assessed to determine the strengths and weaknesses of the existing documents. Overall, the codes had well-defined objectives, good planning information and clear communication. The weaknesses included regulatory approach, comprehensiveness, foundation (particularly stakeholder involvement), monitoring information and review process. The proposed national code of practice, if introduced, should be a prescriptive code. A prescriptive code is better than an outcome-based code because it is difficult to prove liability for sedimentation and erosion. Compliance with a prescriptive code should be like liability insurance, so that if a corporation is fully compliant with a prescriptive code of practice, it should not be held liable for adverse environmental impacts. This is a preliminary recommendation only, as the external conditions operating in New Zealand still need to be investigated.

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  • The biologies of two species of weta endemic to the Snares Island : Zealandrosandrus subantarcticus Salmon (Orthoptera : Stenopelmatidae) and Insulanoplectron spinosum Richards (Orthoptera : Rhaphidophoridae)

    Butts, Christine A. (1983)

    Undergraduate thesis
    University of Canterbury Library

    The life histories, behaviour, diet, habitat, and diurnal activity patterns of two species of Snares Island weta, Zealandrosandrus subantaraticus and Insulanovlectron spinosum, are presented. The males and females of Z. subantarcticus had 12 instars. The males of I. spinosum had 9 instars while the females had 10 instars. Eclosion, moulting, inter- and intraspecific interactions, oviposition, and cannabalism are described. The diet of both species included arthropods, plant material, and dead seabirds. Descriptions of abdomina-femoral stridulatory apparatus for both species are presented. Reproductive parameters and sex ratio of both species were examined. Diurnal activity patterns showed an increase in activity half an hour after sunset and a decrease half an hour before sunrise for both species. These species of weta from the Snares Island showed similarities in aspects of their biologies to those of mainland species

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  • To be Made Disabled, A Discourse Analysis of Intellectual Disability in New Zealand, 1900 - 1960

    Burt, Lucy (2013)

    Undergraduate thesis
    University of Canterbury Library

    The New Zealand historiography on intellectual disability has been expanded in the twenty years by histories of the residential institution and the foundation of advocacy groups. However, there is still a limited field of history regarding how the intellectually disabled were discussed in twentieth century New Zealand. This thesis will discuss how the identity of the intellectually disabled was constructed as a social category, through different discourses, in twentieth century New Zealand. It shall be argued that from 1900 to at least 1960 those who created medical, government and public discourse also maintained the power to create the identity of the intellectually disabled. This argument will take the form of a discourse analysis and will draw on both primary and secondary sources. The primary sources will include government documents, medical literature and newspaper content. The secondary sources will cover material which provides context, and / or which has discussed the construction of intellectual disability. It will be argued that discourses centred on an idea of a 'problem' within the intellectually disabled individual. Also, the medical discourse and 'medicalized' understandings of intellectual disability will be seen to influence public and government discourse. Further, a tension will be shown in these discourses between the desire to assist the intellectually disabled and their families, as well as to protect the New Zealand community from these people.

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  • A History of the Seabrook McKenzie Centre Christchurch 1973-2013

    Hughey-Cockerell, Ngaio (2013)

    Undergraduate thesis
    University of Canterbury Library

    The history of the Seabrook McKenzie Centre is closely connected with a thirty-year campaign by parents and professionals for official recognition of specific learning disability as a category and for a remedial service to address the needs of children affected to be provided within mainstream schooling in New Zealand. This paper focuses on the contribution of the two professional women, Dr Jean Seabrook and Mary Cameron-Lewis who stand out, along with the patron and benefactor Sir Roy McKenzie as making a substantial contribution to the development of the Centre. Inadequate recognition by the Department of Education of children with specific learning disabilities led to the need for a separate, private, facility. This essay discusses the significance this played in contributing to the opening of the initial Centre, the subsequent expansion of the Seabrook McKenzie Centre, and the eventual opening of a school. It argues that the lack of official recognition and provision of support for these children's learning needs played a major role in the history of the Centre's establishment and continues to be a factor in its operation today.

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  • Race relations in New Zealand Through an Analysis of Broadsheet Magazine 1972-1989

    Hayes, Kimberley (2013)

    Undergraduate thesis
    University of Canterbury Library

    This research essay addresses race relations within the context of New Zealand second wave feminism, 1972-1989. The 1970s and 1980s are decades recognised for the increased tension in the relationship between Maori and Pakeha society. I argue that race relations were a crucial aspect of second wave feminism in New Zealand at this time. This history is signified by an important primary source, the New Zealand feminist magazine Broadsheet. I argue that the progression that Maori women made over time to gain a space within New Zealand second wave feminism reflected deeper issues of race relations in wider New Zealand society. Themes that emerge from a close analysis of Broadsheet magazine include Maori women's questioning of the relevance of New Zealand second wave feminism for them, the important contribution that Maori women made to New Zealand second wave feminism, and the growing but necessary confrontation between Maori and Pakeha women.

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  • Executioners of Convenience - The Wehrmacht's Atrocities on the Ostfront. Genocide and Ideology in a War of Annihilation, 1941-1943

    Cheer, Michael (2013)

    Undergraduate thesis
    University of Canterbury Library

    Abstract This thesis explores to what degree the Wehrmacht was involved in atrocities on the Eastern Front and the structures that led to this involvement. The goal is to show that the men of the Wehrmacht were incorporated more completely into a genocidal 'war of annihilation' than has been previously thought. It will be demonstrated that the Wehrmacht Heer on the Ostfront cannot be understood as a traditional army conducting a conventional war. However, it was not made up of rabidly anti-Semitic 'willing executioners' either. This research is based mainly on perpetrator testimony, including secret POW recordings, official Wehrmacht documents and soldiers testimonies. Upon examination of these documents, it becomes clear that Wehrmacht Heer units during the Ostkreig were instructed and prepared not only to assist the SS and Einsatzgruppen in prosecuting the Final Solution, but also to act independently as a kind of 'vanguard' of annihilation in their area of operations. In contrast to existing interpretations however, this thesis will argue that in general soldiers did not commit war crimes due to Nazi indoctrination/ingrained anti-Semitism or through peer pressure and brutalisation but because of indiscriminate rules of engagement set within an extremely rigid military structure, which explicitly equated Jews with Bolshevik partisans while considering Soviet POWs and civilians to be expendable.

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  • You Wouldn't Know There Was a War On. A Cultural History of New Zealanders Serving in Bomber Command during the Second World War.

    Kimberley, Aidan (2013)

    Undergraduate thesis
    University of Canterbury Library

    The intention of this project is to reconstruct the culture of New Zealanders serving in Bomber Command of the RAF during the Second World War. Similar work has emerged on the culture of British airmen but cultural histories looking specifically at New Zealand airmen are yet to emerge. In conducting a cultural history of this subject, this paper looks more closely at the airmens' behaviour, routines and emotions. To achieve this, it will focus on three main aspects of the New Zealanders' culture: rivalries, leisure and attitudes. Rivalries were commonplace and include sporting contests, which were encouraged as a morale boosting tool, tensions between members of aircrews, and also a bitter rivalry between Englishmen and New Zealanders which was caused by unpopular decision making by a handful of English commanders. Forms of leisure were particularly varied. Tourism was an activity New Zealanders commonly indulged in, as was visiting friends and extended family on leave, and frequenting the local concerts and stage shows. However it became clear that they had not quite grown out of their rebellious teenage selves as unsanctioned activities such as joy riding and pranks emerged. In the final chapter it is shown that the cheerful demeanour the men tried to present was the result of self-censorship to protect their families, and that once they began experiencing horrifying situations this demeanour became much harder to maintain.

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  • A Most Excellent Thing: The introduction of brown trout (Salmo trutta) to Canterbury, New Zealand 1864-1872

    Kos, Jack (2013)

    Undergraduate thesis
    University of Canterbury Library

    This essay examines the process undergone in the Canterbury province in the late 1860s and early 1870s to import Salmo trutta (brown trout) ova from Tasmania, to hatch them out and to distribute them throughout the waterways of the province. This essay seeks to answer two questions. First, how were trout introduced? Second, why was their introduction of such significance to colonists at the time? To answer these questions this essay draws upon a comprehensive range of primary sources including Society records and newspapers. The successful importation of trout represented one of the key early achievements of the fledgling Canterbury Acclimatisation Society at a time when several other attempted introductions were failing. The process undertaken to import the ova, rear hatchlings and distribute the �young trout� tested the scientific knowledge of the 1860s and 1870s. It necessitated significant interaction with international acclimatisation groups primarily in Australia but also further afield. This essay also attempts to convey the significance of the importation to Canterbury. Such was the public interest that the coverage of trout in print media extended to the hatching of individual ova or the sighting of escaped trout. Trout were afforded a romanticised status in colonial New Zealand society, largely as a result of their construction as a quintessentially British object. Their importation was motivated by several factors, namely the re-creation of a British ecology in New Zealand, the recreational opportunities they afforded and the food source they provided.

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  • Past within the Plot: Two Narrative Historians and their Discontents

    Vesty, Julian (2013)

    Undergraduate thesis
    University of Canterbury Library

    This dissertation examines the coexistence of 'narrative', popular history, which aims to tell a story to edify and entertain, with 'structural' history, which gained precedence in the university from the nineteenth century onward. Using the case studies of Simon Schama and Niall Ferguson, popular historians who transitioned from early 'structural' works to 'narrative' books and finally documentary, the precise nature of narrative is examined through the theory of literary historical tropes developed by Hayden White, where a political perspective engages an 'emplotment' where a form of narrative develops. After examining how tropes apply to the life experience, ideology and resulting emplotment of Schama and Ferguson, it looks at the academic criticisms of their narratives, in text and television documentary - namely, that the organisation of data into a compelling story negates accuracy and objectivity in the name of entertainment. Subsequently, the similarity of Schama and Ferguson's narrative style is compared to pre-academic historical writings from before Leopold von Ranke. The final argument is that the popular history espoused by Schama and Ferguson is a re-emergence of the older, pre-academic style, based on narrative, which predates the structural history which displaced it. This dissertation concludes by examining how the two historiographies might coexist, arguing that the new narrative can offer excitement and purpose to the structural historian, giving relevance to the rigorous work of structural history.

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  • ‘He’ll do the right thing’: A discussion of Jimmy Carter and Ronald Reagan’s relationship with the Evangelical community

    Hart-Smith, Alexander (2013)

    Undergraduate thesis
    University of Canterbury Library

    Historiographical scholarship of previous presidents is never short in supply. James Earl Carter and Ronald Wilson Reagan are no exception to this assertion and have been extensively studied by historians. Similarly, the role of religion in politics in the United States is rarely neglected by historians. The role of the Religious Right in politics and the explanation for its emergence has also been well documented by academics. There is however a surprising lack of investigation into the specific issue of how Regan, the arguably less religious man, became more commonly identified with the Religious Right than Carter. Using both a mixture of primary and secondary sources this paper attempts to answer the question of why Carter's electoral success with Evangelicals was so short-lived. Utilizing remarks from the Presidents, their former advisors, debates and prominent Evangelical leaders this dissertation seeks to offer a new insight into why the support for Jimmy Carter was so ephemeral. This dissertation will offer a rather simple resolution to the complex question of why Evangelicals shifted their support to Reagan. The Religious Right were not just interested in the election of a pious President but wanted to transform the governance of a nation after two decades of growing secularism. Ultimately it appears that Carter's decision to campaign on little more than his moral image propelled him into the White House as this title of this thesis suggests because voters and most specifically Evangelicals believed,

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  • Re-excavating Wairau: A study of New Zealand repatriation and the excavation of Wairau Bar.

    Hickland, Shaun (2013)

    Undergraduate thesis
    University of Canterbury Library

    Repatriation is an increasingly significant issue in the museum world. It is concerned with the return of cultural artefacts that have been previously traded or sold into foreign countries or institutions, either at the behest of the indigenous people or the initiative of the institution holding them. This dissertation explores the role of repatriation in modern New Zealand museums and its role in furthering the often contentious relationship between Maori and museum staff. It has a specific focus on the excavation and repatriation of human remains at Wairau Bar in Marlborough. It critiques an unpublished history of the Bar written by independent historian David Armstrong, which was commissioned by Rangitane in 2009. My overall argument disputes Armstrong's portrayal of Roger Duff, ethnologist at the Canterbury Museum, as the leader of a surreptitious excavation who was consistently underhand and secretive in his dealings with Rangitane. I counter Armstrong's claims to demonstrate that Duff valued an open and transparent relationship with Rangitane and respected their cultural attitudes to ancestral remains. I conclude that these remain core values in both modern repatriation policies and museum relations with Maori. My contextual discussion draws largely on secondary scholarship and journal articles while my conclusions about Wairau Bar are largely based on primary archives and Armstrong's report.

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  • Andrew Miller and his Eagles - American Citizens, British Subjects and Rights in the ImpressmentControversy

    Rennie, Connor (2013)

    Undergraduate thesis
    University of Canterbury Library

    In 1812 impressment was left as the implied cause for the outbreak of war between Britain and the United States of America. Scholars have focused on how impressment was involved in diplomacy. There remains, however, a lack of investigation into the justification of impressment. This dissertation explores the impressment of Americans by the Royal Navy and the resulting fallout. The research will focus on one group in particular: naturalised American citizens. The aim is to show that the conflict over impressment stemmed from Britain and America possessing different conceptualisations of citizenship and rights. The dissertation examines the history of impressment in Britain and the doctrine of indefeasible allegiance together with American arguments against the doctrine. This research is based on the correspondence of politicians, treatises, laws and secondary scholarship. Using these sources a narrative of diplomacy and rights will be constructed. Upon the examination of the evidence it becomes clear that American claims about the unjustness of the impressment of naturalised American citizens are wrong. While there was a dispute if naturalisation could occur, the fact is that the American government loudly disputed the British right to reclaim a large number of naturalised sailors when by the laws of America these sailors were not naturalised.

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  • Molecular phylogenetics of Antarctic Sea spiders (Pycnogonida)

    Nielsen, Johanna Fønss (2005)

    Undergraduate thesis
    The University of Auckland Library

    Whole document restricted, but available by request, use the feedback form to request access. Sea spiders, or pycnogonids, are a unique group of exclusively marine invertebrates that are found worldwide. A scarcity of pycnogonid research is reflected in the unclear position of this group with regards to the phylum Arthropoda and lack of certainty in their family-level phylogeny. Traditionally, the pycnogonid phylogeny has relied on the external morphological characters of temperate, shallow water species. The Antarctic sea spider fauna displays a high degree of endemism and a number of species have the potential to address several long-standing questions regarding the pycnogonid evolution. This research uses new sequence data from Antarctic species to provide the most complete molecular phylogenetic reconstructions of the Pycnogonida, and is the first study to formally test a number of alternative hypotheses on the interfamilial relationships of this group of organisms. The BioRoss 2004 pycnogonid collection was classified into 18 different OTUs (5 families & 10 genera) and used, in combination with publicly accessible sequences, to provide samples for this study. Partial regions of the nuclear 18S and 28S rDNA, mitochondrial 12S and 16S rDNA and protein coding COI loci were sequenced for each dataset, and the concatenated data tested for incongruence using the Partition of Homogeneity test. The distance based Neighbour Joining and character based Maximum Likelihood tree-building algorithms were used to reconstruct the pycnogonid phylogeny for each locus independently and as a concatenated dataset. A series of alternative evolutionary hypotheses based on previous studies were examined via the Shimodaira-Hasegawa test. The primary hypothesis examined was the cephalic appendage reductive trend, which implies that ancestral sea spider taxa possess the greatest complexity of anterior appendages. On all the individual locus trees the family Nymphonidae were the earliest diverged lineage of pycnogonids, although low resolution at the roots of the trees implies that the data are not strong enough to reject an alternative hypothesis of a basal Ammotheidae group. Pycnogonidae is not the most recently derived sea spider family and the cephalic appendage loss hypothesis is thus rejected. None of the phylogenies supported a close relationship between the Colossendeidae and Nymphonidae families and doubt is raised over the true identification of several GenBank sequences. Polymerous species do not form a combined, ancestral group but are instead more likely to represent recent divergences from three separate families. Strong evidence supports the placement of the transient Austropallene genus (Callipallenidae) at the base of the Nymphonidae family. This study, and ongoing work, has generated large amounts of new sequence data. This can be used in future pycnogonid phylogenetic research and/or in investigations on the highly contentious position of the Pycnogonida with regards to the phylum Arthropoda. A DNA Surveillance website has been created to assist in the molecular identification of pycnogonids from future benthic bio-discovery expeditions (http://www.dna-surveillance.auckland.ac.nz).

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  • The geology and eruptive history of the Table Mountain region, Coromandel Peninsula

    Hayward, Bruce W. (Bruce William) (1971)

    Undergraduate thesis
    The University of Auckland Library

    The Table Mountain region covers an area of 2,200 hectares, 17 kilometres north-east of Thames, and straddles the main Coromandel Peninsula Divide between the headwaters of the Kauaeranga and Waiwawa Rivers. It is a region of steeply dissected, bush clad slopes and rugged bluffs composed of andesite, rhyolite and sediments. These rocks belong to three Groups. The oldest group of rocks consists of andesite lavas, breccias and sediments that form the upper part of the Beesons Island Volcanics sequence and were erupted during the upper Miocene and lowermost Pliocene. Unconformably overlying these is the mid Pliocene Whitianga Group containing rhyolitic lavas and sediments. In the Table Mt. Region this Group has been divided into the Minden Rhyolites and two informal sedimentary formations. The Wainora Formation contains basal volcanic breccias and freshwater, carbonaceous, epiclastic sediments that were deposited in two lakes on the dissected surface of the older andesites. This formation contains impressions of fresh-water mussels and numerous leaves, as well as considerable amounts of silicified wood. Conformably overlying the Wainora Formation are the thicker and more extensive water and aerially deposited pyroclastic sediments and rarer ignimbrites of the Waiwawa Formation. Many of the water laid deposits are inferred to have been formed by hot pyroclastic flows entering a lake. Minden Rhyolite domes were produced, by endogenous and exogenous growth, towards the end of this phreatic eruptive period. Hydrothermal alteration is inferred to be closely associated with the four Minden Rhyolite domes of this region. During the upper Pliocene to lower Pleistocene, the Omahia Andesite Group was intruded. The narrow Waiwawa Intrusive came up along an old intrusive contact between a Minden Rhyolite dome and the Waiwawa Formation sediments. The large Table Mt. andesite mass is believed to have formed by a combination of upwelling of lava along a fissure and actual intrusion. Both the Waiwawa and Table Mt. Intrusives spilled small amounts of lava out over the surface as lava flows. In the two million years since the cessation of volcanic activity in this region, erosion has greatly altered the landscape and emphasized the harder rock masses.

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  • Another Look at the Faunal Remains of CA-SCR-9

    Nims, Reno (2011-06)

    Undergraduate thesis
    The University of Auckland Library

    CA-SCR-9 is an important early Middle Period (3100-2800 cal BP) site from the California central coast region that has been used to characterize residential base camps from that time. Previous studies have attempted to analyze the fauna using incomplete and non-representative samples, creating multiple, contradictory conclusions about the foodways of Middle Period peoples. The goal of this study was to synthesize and analyze all identified material to answer questions about the seasonal use of SCR-9, differences between two possible phases of occupation, and the adaptive strategies of Middle Period peoples on the California central coast. Using a representative sample of the fauna, this paper finds that SCR-9???s inhabitants primarily preyed upon mule deer. However, diverse species of marine mammals, leporids, terrestrial carnivores, birds, and marine fishes were also deposited at SCR-9, and inland site. The faunal remains from SCR-9 alone are not enough to identify relationships between sites, but these marine materials suggest that SCR-9 may have functioned as a seasonal or year round habitation site from which Middle Period peoples traveled to coastal sites such as SMA-218, which is nearly contemporaneous with SCR-9. Other writers have argued that two separate phases are represented ad SCR-9, including the Sand Hill Bluff Phase and the later A??o Nuevo Phase. The fauna from these two phases is extraordinarily homogenous, suggesting there were no changes in adaptive strategy, or that rodent activity has mixed the materials, making it impossible to compare fauna from the Sand Hill Bluff and A??o Nuevo phases. Fortunately, the assemblage does shed light on differential handling of taxa, and raises questions about the nature of bone grease extraction practices.

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  • The prevalence and level of education of Hepatitis C Virus among an asymptomatic population

    Vermunt, Jane (2014)

    Undergraduate thesis
    University of Otago

    Background The burden of Hepatitis C virus (HCV) is projected to increase substantially over the next 2 decades as a result of complications arising from chronically infected individuals who remain undiagnosed and untreated. Accurate epidemiological data on the prevalence and demographics of Hepatitis C is therefore needed to allow efficient planning of services and resource allocation for prevention and treatment management in the region. In order to minimise transmission and to recognise risk factors and symptoms of HCV infection, population-wide education is also essential. Aim This study aimed to identify the prevalence of Hepatitis C among the 40 to 59 year old population living in urban Dunedin. It also set about to identify gaps in knowledge about HCV in the target – assessment of HCV knowledge among this cohort was thought to be important to gaining better understanding any barriers to identification, diagnosis and treatment while concurrently raising awareness of the issue. Method A total of 1400 individuals aged between 40 and 59 living in urban Dunedin were randomly identified from the electorate role. A questionnaire was developed and posted to participants that explored risk profile, infection transmission, complications, symptoms and treatment. Participants were also asked to provide a blood sample for anti-HCV and HbsAg testing. Hepatitis B antigen testing (HbsAg) was also tested to allow comparison on prevalence and decrease perceived stigma of testing. Results Of the 1400 questionnaires sent, a total of 432 were returned completed and some 306 blood samples were analysed. The prevalence of HCV and Hepatitis B virus (HBV) was estimated to be less than 0.98%, based on a zero numerator. Significant knowledge gaps were identified. The average correct score from the questionnaire was 59.4%. Both adjusted and unadjusted logistic regression modelling showed that three demographics were statistically significant predictors of an individuals’ score. On average females scored 5.4% higher. Every increase in qualification level showed a 5.0% increase and a 4.8% increase was found between each occupation sector. No statistically significant relationships were found between socioeconomic status (SES) or age. The population sample recognised all the potential modes of HCV transmission. Only 23% correctly estimating the assumed prevalence of HCV. 93% of the sample population did not recognize that an acute or chronic infection may be asymptomatic and 97% were unaware that there could be no long term sequale to a chronic infection. 23.6% knew that it takes years rather than months weeks or days for symptoms of complications of a chronic infection to become apparent. Twenty-two per cent were aware that there is no available vaccine, 34.0% do not know that HCV can be treated and of those who do know, only 39.7% are aware that this is funded by the government. Conclusions The prevalence rate, although inferred, is lower than expected. Our group has thus committed to undertaken further work in this area to obtain a more representative sample of bloods from which to draw better prevalaence data – though completed, data was not ready for publication in this thesis. The lack of general knowledge about HCV is of concern as this population is at high risk of transmission and of developing complications related to unassumed chronic infection. It is clear that the majority of this population is unaware of the asymptomatic nature and when the nonspecific symptoms of an HBC or HCV infection are likely to manifest. Further, one-third of the population are unaware that HBV and HCV can be treated and two-thirds are unaware that treatment is fully funded. Well educated women working in the health or white collar sector have the best knowledge about risk of transmission, possible symptoms and treatment. Educational efforts to increase awareness empower people to be aware of symptoms, get diagnosed and undergo treatment needs to target all other population groups.

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  • The origin and development of Gore and its surrounding districts

    Kerse, Elizabeth (1943)

    Undergraduate thesis
    University of Otago

    vi, 117 leaves :ill. ; 30 cm. Includes bibliographical references (leaves 85-93) Typescript.

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  • A novel genetically encoded voltage indicator for studying motor cortical circuitry

    Scholtz, David Johannes (2014)

    Undergraduate thesis
    University of Otago

    The primary motor cortex (M1) consists of layers that are occupied by distinctive excitatory pyramidal neuron and inhibitory interneuron populations. Neurons within each layer receive inputs from numerous cortical and subcortical structures that relay proprioceptive and sensory feedback to modulate motor outputs and facilitate motor learning. The neurons within the upper layers (layer 2/3) are linked with processing and integrating these inputs and activating the circuitry that generates motor output commands that drive voluntary movement. To date our understanding of how these circuits achieve this remains elusive. Our poor understanding arises from technical challenges associated with studying the simultaneous behaviour of the electrical activity of the vast diversity and complex connections of the neurons within these circuits. To overcome this limitation we aim to use a Genetically Encoded Voltage Indicator (GEVI) called VSFP-Butterfly 1.2 that is endogenously expressed in layer 2/3 pyramidal neurons M1 in a transgenic mouse. We aim to determine the fidelity of VSFP-Butterfly 1.2 expression in the transgenic mouse and its ability to report subthreshold synaptic fluctuations in electrical membrane potential as changes in fluorescence. VSFP-Butterfly 1.2 is engineered to be expressed in layer 2/3 pyramidal neurons downstream of the Ca2+ Calmodulin-dependent protein kinase 2 (CAMKII). Immunohistochemistry for CAMKII in layer 2/3 of M1 slices found that the majority of neurons that express VSFP-Butterfly 1.2 also clearly express CAMKII (99.24 ± 0.567 %, n = 9 slices from 6 mice). Simultaneous recording of local field potential (LFP) and VSFP-Butterfly 1.2 fluorescent optical signals from layer 2/3 of slices from the M1 in response to extracellular electrical stimulation revealed a clear voltage-response relationship for VSFP-Butterfly 1.2 (n = 8 slices from 4 mice). Pharmacological excitatory synaptic antagonists dampened both the optical VSFP-Butterfly 1.2 (P < 0.0001, One-way ANOVA multiple comparisons, n = 4 slices from 2 mice) signals and LFP responses (P < 0.0001, One-way ANOVA multiple comparisons, n = 4 slices from 2 mice); and all responses were eliminated by tetrodotoxin which is known to block all voltage dependent electrical activity in neurons (P < 0.05, One-way ANOVA multiple comparisons, n = 2 slices from 1 mouse). In addition, we provide evidence that VSFP-Butterfly 1.2 can report membrane potential fluctuations at distances as far as 793.6 μm from the recording column (P < 0.0001). Our results show that VSFP-Butterfly 1.2 is reliably expressed exclusively in layer 2/3 neurons of the M1 in the transgenic mouse where it accurately reports physiologically relevant electrical synaptic responses. Our validation supports the future use and exciting benefit of this mouse to begin to understand the basis of network and circuit connectivity during motor output and motor learning.

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  • Wnt signalling influences T cell phenotype in a novel intestinal immune system model

    Worters, Thomas David (2014)

    Undergraduate thesis
    University of Otago

    Inflammatory bowel disease (IBD) is a collective term for inflammatory conditions that affect the gastro-intestinal tract. These conditions feature a multifactorial etiology: an interplay of genetics, environmental exposures, the immune system and commensal microbiota, all of which converge at the intestinal epithelia. The ability to understand IBD is dependent on and limited by the model systems used to study it. We have developed an ex vivo model of the human intestine by co-culturing intestinal organoids and PBMCs from the same patient. As intestinal organoids accurately mimic the intestinal epithelia, this allows us to study the interaction of the epithelium and immune system on a controlled genetic background in both IBD patients and healthy individuals. I hypothesise that intestinal organoids cultured with immune cells will create an environment similar to the human intestinal immune environment. The aim of my research was to develop a platform to study the role of immune cells in this organoid culture. I analysed the effect of organoid culture conditions on the survival and phenotype of immune cells, measured by cytokine and cell surface receptor expression. PBMCs remained viable for four days when grown in DMEM, and this viability was not affected by suspending the cells in the Matrigel used for organoid culture. Freezing and thawing PBMCs, which is required to allow establishment of the organoids, only caused a slight reduction in viability, and did not affect the frequency of Th1, Th17 and regulatory T cells. Introduction of growth factors required for organoid culture did not affect viability of the PBMCs, however the frequencies of Th1 and Th17 but not regulatory T cells were reduced. Recombinant Wnt, a key component used to culture organoids, affected the ability of regulatory T cells to maintain but not differentiate their phenotype. Finally, viable T cells could be removed from a complete PBMC-organoid co-culture. These data indicate that PBMCs can be successfully cultured in conditions used to generate intestinal organoids without loss of viability or major changes in phenotype. Furthermore, this co-culture model will likely serve as an accurate model of the intestinal immune system and may aid in the search of an effective treatment for IBD.

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  • A novel technique to investigate coronary microvascular perfusion in diabetes

    Nissen, Hazel Merete (2014)

    Undergraduate thesis
    University of Otago

    Diabetes Mellitus (DM)-induced disease of the coronary microvessels contributes to the worldwide increase in cardiovascular morbidity and mortality in diabetic patients. These microvessels are vital to the regulation of regional blood flow, and facilitating oxygen and nutrient exchange within heart tissue. Whilst total coronary blood flow is readily measured, our limited ability to directly measure coronary microvascular perfusion has restricted our progress in understanding DM pathology. Therefore, I aimed to test the feasibility of adapting two techniques previously used in skeletal muscle, 1-methylxanthine metabolism and vascular casting, to measure coronary microvascular perfusion and assess how this is impaired in type 2 DM. Isolated rat hearts were perfused under physiological conditions, with assessment of cardiac contractility and total coronary flow. This was combined with investigation of both a chemical and physical approach to assess microvascular perfusion. Firstly, metabolism of exogenous 1-methylxanthine (1-MX) by xanthine oxidase on the endothelium was investigated as a measure of capillary surface area. In addition, casts of the physiological vascular structure were produced using rapidly setting dental acrylic injected into the coronary vasculature, and visualised with micro-computerised tomography. To examine the feasibility of these microvascular measures, protocols were developed to induce known perfusion changes in male Sprague Dawley rat hearts; isoproterenol (1x10-8M, vasodilation) and angiotensin II (1x10-7M, vasoconstriction) were applied. Secondly, a pilot study was conducted applying the 1-MX and casting techniques to compare 20-week-old male type 2 DM Zucker Diabetic Fatty (ZDF) rats to their non-diabetic littermates. In Sprague Dawley rats, isoproterenol significantly increased whilst, to a lesser extent, angiotensin II significantly decreased myocardial function and coronary flow (p≤0.05, n=6 and 7). Vascular casting produced promising results; a representative cast from the isoproterenol intervention displayed increased branching, and the angiotensin II intervention showed somewhat reduced branching of the microvessels relative to no intervention (n=1). However, 1-MX values did not reveal any changes between these interventions. Consequently, the 1-MX protocol was optimised to improve stability, before being applied in the type 2 DM pilot study. Under basal conditions, no significant difference was discerned between diabetic and non-diabetic rats in 1-MX disappearance (22.6±6.7nmol/min (n=5) vs. 23.4±3.9nmol/min (n=3); mean±SEM: n.s.), nor in measures of cardiac function. Likewise, no difference was discernible between a representative cast from the non-diabetic and diabetic group. However, a positive Spearman’s rank correlation was observed between coronary flow and 1-MX disappearance in the diabetic rats (rs=1, p≤0.05). With this study I have set up the foundations of using 1-MX metabolism and vascular casting, as techniques to examine coronary microvascular perfusion in the isolated heart. Conclusions regarding DM-induced changes cannot be drawn at this stage. However, pilot data provide valuable information on how to further develop these techniques. Novel measures of coronary microvascular perfusion have the potential to enhance our understanding of coronary microvascular pathology, and eventually reduce DM-induced cardiovascular complications.

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