51 results for Undergraduate, 2015

  • Falcon Forestry Carriage Series 2 : a case study of productivity and operation.

    Bolitho, Callum (2015)

    Undergraduate thesis
    University of Canterbury Library

    The multiple drivers of workplace safety and increasing productivity are resulting in increased mechanisation within the forestry industry. The use of motorised grapples in cable harvesting is an applicable mechanisation method to the large proportion of steep terrain harvesting in New Zealand. In this dissertation a time study of the Falcon Forestry Carriage Series 2 has been undertaken in order to access its productivity and operation. Mean values of productivity were found to be 54.9m³/PMH for wood extracted from the ground, 64.6m³/PMH for bunched wood and 75.6m³/PMH for excavator fed wood after adjustment for the cycle distance and accumulation type. Longer cycles were found to decrease productivity by 0.15m³/PMH for each meter of cycle distance. Utilisation in the study was found to be 56% of total time which was similar to previous studies. 15% of total study time was accounted for by operational delays, 7% by personal delays and 23% by mechanical delays. Mechanical problems with the carriage occurred 6 times and accounted for 171 minutes or 13.4% of total delay time. Mechanical delay breakdown was similar to that found by McFadzean (2012) who recorded that 15% of total delay time was attributable to carriage mechanical delays. During a study of Operator effect it was found that the inexperienced Operator 3 and Operator 4 had a productivity of 52.2% (not statistically significantly different) and 18.5% (p value <0.05). The effects of accumulation method and cycle distance upon productivity were found to be similar to the results of previous studies, as was the utilisation of time within the study.

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  • Understanding demand for wood products in New Zealand’s major log markets.

    Drummond, Ryan C.M. (2015)

    Undergraduate thesis
    University of Canterbury Library

    New Zealand’s forestry sector is largely reliant on the presence of a strong export market with 57% of the volume harvested being exported of which 99% goes to Japan, the Republic of Korea, China and India. This identifies the need to analyse demand in these countries to better understand their needs in the future. Consumption of wood products per capita is a commonly used metric for estimating demand and was used in this research. Volumes of imports, exports and production were collected from the Food and Agricultural Organisation of the United Nations (FAO) and data for a range of explanatory variables was collected from a variety of official sources. Historical trends in consumption identified that as countries develop socially and economically their consumption shifts from largely solid wood products such as sawn timber to more processed products such as wood-based panels and paper and paperboard. Consumption was modelled using linear regression techniques to develop models which could be used to forecast consumption in the future. A wide variety of potential explanatory variables were considered and the models presented represent the most effective of these. GDP per capita was found to be the single most effective explanatory variable being highly significant (p<0.01) in all models. Price was also found to be a strong determinant of consumption, understandable as price is a major component of supply and demand dynamics. Measures of construction activity were found to be related to consumption of sawn timber in all studied countries and for wood-based panels in Japan. Forecasts produced for consumption in Japan should be used as only an example of the capability of the models presented herein. More work is required to develop these equations into a form where they can be used to more accurately estimate future consumption.

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  • The performance of blocks of clones in a radiata pine production forest.

    Farmery, Acacia (2015)

    Undergraduate thesis
    University of Canterbury Library

    Problem: Genetically identical clones of Pinus radiata are being planted in New Zealand plantation forests. There have been many clonal trials carried out; however there is a weakness in published literature surrounding the performance of clones in production blocks. Method: Five comparisons in four of Pan Pac Forests Products production forests were measured. Three comparisons were measured at age 4.5 years old and two were measured at 7.5 years old. There were six Forest Genetics clones and three different control-pollinated seedlots measured in these comparisons. Each comparison had a different number and selection of seedlots. There were six different traits measured for the trees; diameter at breast height over bark, height, acoustic velocity, straightness, branching habit, and malformation. The different traits were compared between the seedlots within each comparison. The differences in variation for diameter at breast height and modulus of elasticity were compared between clones and control-pollinated seedlots. Finally, the results by clone for the traits, excluding height, were compared to the expected performance supplied by Forest Genetics. Results: There were differences in performance between seedlots. Four clones performed well across a range of traits. One clone performed well in the 7.5 year old blocks but not in the 4.5 year old blocks. One clone did not perform well in size and stiffness. Clones were significantly less variable than control-pollinated seedlots for diameter at breast height but not for modulus of elasticity. The performance of each clone in Pan Pac Forest Products forests was very similar to the expected performance provided by Forest Genetics. Implications: There are clones that can produce desired yield, stiffness and form. Clones will provide a more uniform crop in diameter than control-pollinated seedlots. Pan Pac Forest Products can rely on Forest Genetics prediction of clonal performance as a guide to performance in their forests.

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  • A comparative study of the influence that motor-manual felling and mechanised felling has on stem breakage.

    Andrews, S. D. (2015)

    Undergraduate thesis
    University of Canterbury Library

    Motor-manual felling has been the predominate method of severing trees in the felling process of a forest harvesting operation. Yet this method has been coupled with numerous injuries and deaths, as trees can strike fallers during this task. An alternative felling method was developed in the form of mechanised tree felling, in an attempt to reduce the frequency of injuries. Subsequently, mechanised felling is poorly understood when compared to motor-manual felling upon the impact it has on stem breakage. 183 trees were assessed by measuring the frequency of breakage, height of the first break and the volume retention abilities of three felling treatments; motor-manual, mechanised felling out of the stand and mechanised felling into the stand. The effect that directional felling had upon the length to the first break was also investigated for motor-manual and mechanised felling out of the stand. The percentage of stems that broke once felled was 73%, 76% and 94% for motor-manual, mechanised out of the stand and mechanised into the stand felling respectively. The height at which the first break occurred for the aforementioned felling treatments was 71%, 71% and 69% of the total tree height. Mechanised felling out of the stand had the greatest volume retention ability with 94.5% of the trees total volume being below the first break. Followed by 93.7% for motor-manual and 91.9% for mechanised felling into the stand, however these differences were statistically insignificant (p=0.14). Lastly the length to the first break for motor-manual and mechanised felling out of the stand failed to statistically change when a tree was felled through a range of directions from downhill to uphill. The influence that motor-manual felling and mechanised felling out of the stand had on stem breakage is similar, yet mechanised felling into the stand had a much greater impact on the percentage of stems that broke. With further improvements in technology, it could be seen that the number of mechanised tree-felling operations over take motor-manual felling, as their impact on stem breakage is comparable.

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  • Genetic parameter estimates for growth traits of Eucalyptus bosistoana : assessment of two progeny trials in Marlborough, New Zealand.

    Burgess, Jack (2015)

    Undergraduate thesis
    University of Canterbury Library

    This paper presents a follow up study to that was already completed by Luis et al. (2011). Luis et al (2011) investigated the survival of E. bosistoana half-sib families within two progeny trials in Marlborough, New Zealand. The study investigated genetic growth parameters of the same two progeny trials. Trees at Craven (progeny trial) were statistically taller and larger in diameter than Lawson (other progeny trial), which is likely to be a result of thinning occurring one year earlier at the Craven and Lawson North sites than at the Lawson East site. The progeny trials were set up into randomized incomplete blocks which allowed effective calculations of fixed and random effects from a mixed-effect linear model. The family, incomplete block and residual variances from the mixed-effect model made heritabilities of growth traits possible to calculate. Narrow sense heritabilities for diameter at breast height ranged from 0.13 to 0.18, while tree height heritabilities ranged from 0.1 to 0.17. The inter-site correlation of family performance was weak to moderate for both height;  Craven : Lawson North = 0.28  Craven : Lawson East = 0.44  Lawson East : Lawson North = 0.27 And diameter at breast height (dbh); Craven : Lawson North = 0.32 Craven : Lawson East = 0.39 Lawson East : Lawson North = 0.36 Heritabilities were weak to moderate for growth traits but there was substantial variation so selection is still likely to provide sufficient gain. Further studies will need to consider researching the genetic parameters of wood qualities of E. bosistoana.

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  • 'A Light Sniff Might Mean Death’ : Soldiers’ Responses to Poisonous Gas Throughout the First World War

    Annesley, Ellis Jayne (2015)

    Undergraduate thesis
    University of Canterbury Library

    This research paper examines soldiers’ responses to poisonous gas throughout the First World War. Accounts from British and Dominion, American and German soldiers who fought along the Western Front have been collected to analyse the psychological impact gas had upon a variety of men throughout the conflict. Contemporary letters and diaries as well as post-war oral testimonies and memoirs form the basis of the evidence used. The topic encompasses three strands of historical scholarship and engages with each to explore more thoroughly the responses obtained. Emphasis is placed on the psychological impact of gas upon the individuals assessed. Ultimately, this dissertation demonstrates that upon its introduction, poison gas was capable of instilling fear into men whether previously exposed to its consequences or not. However, this psychological power was to significantly diminish following the production and distribution of anti-gas protective measures in late 1916. Despite decreasing anxiety, gas retained its title as a ‘terror weapon’ from effectively inspiring fear into men who were unprotected, ill-prepared, and subsequently vulnerable, in the face of the poison.

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  • Blast From Byzantium : The Alexiad on Crusader-Byzantine Relations During the First Crusade

    Reynolds, Gordon (2015)

    Undergraduate thesis
    University of Canterbury Library

    In order to rest and regroup the pilgrim masses of the First Crusade collected in the city of Constantinople, modern day Istanbul. Thousands answered the call for help from the Byzantine Emperor, Alexios I Komnenos, far more than he anticipated. These crusaders were culturally different from the Byzantines, in need of provisions, fanatical followers of the Latin Church and well armed. This tense situation was made more troubled as Bohemond of Taranto, who had waged a war against Alexios a decade prior, arrived leading a major contingent of the expedition. The complexity of the relationship between these uneasy-­‐allies has been the topic of much debate amongst historians. This historiographical discourse has been intensified by the dearth of written sources from Byzantine eyewitnesses, the only significant source being The Alexiad, by Anna Komnene. Until recently the majority of historians studying the period treated The Alexiad as an unreliable account. Considered by many to be littered with chronological errors and tainted by the musings of an exceptionally opinionated author. Viewpoints like these are rooted in a culture of distrust surrounding The Alexiad and perhaps a conscious movement by commentators to distance themselves from the pro-­‐Hellenic writings of Steven Runciman. This dissertation is an effort to establish the cultural and political context within which Anna Komnene was writing and how her perspectives were entirely representative of contemporary Byzantine thought. As such, The Alexiad can be seen to be a highly valuable resource in studying the Crusade.

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  • Peter the Great and British Perceptions of Russia: A study of how the image of Peter informed British ideas of Russia

    Ng, Wai Nam Boswell (2015)

    Undergraduate thesis
    University of Canterbury Library

    In British eyes, Russia was considered a non-entity before Peter the Great came into the scene. Aside from trade, it was largely irrelevant to British interests. Very few aspects about the nation appealed to the British. Indeed, Russia was considered the home of a group of ignorant, drunken, and brutish people governed by an absolute monarchy. However, by the end of Peter’s reign, Russia was seen in a more positive light. Through the rule of Peter, Russia was able to replace the hitherto powerful Swedish Empire in northern Europe and was firmly established in the Baltic Sea with a powerful navy at its disposal. At the same time, the reforms that characterized Peter’s reign so much also led to a shift in how the British perceived Russia in cultural terms. Breaking a trend that existed close to two centuries, the British began to view Russia as a nation that was progressing towards civilisation at a significant pace. Yet Peter’s image in British eyes was significant in encouraging such changes. Many saw Peter as the heart and soul of Russia, giving rise to a tendency to assess Russia from how they perceived Peter. Throughout his reign, the British came to know Peter for a number of things. He was seen as a competent and ambitious ruler who aimed to raise his empire to the highest degree possible. At the same time, he was also seen as an autocratic reformer who was forcing civilisation upon a backward country. With such images at the back of British minds, it was easy for them to invoke an image of a Russia that was threatening and more civilised than before. These perceptions of Peter therefore helped inform British ideas of Russia in a political and cultural context.

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  • Immaculate Perceptions : Gender and Sanctity in Jacobus de Voragine’s Legenda aurea

    Wilson, Cressida Lilian (2015)

    Undergraduate thesis
    University of Canterbury Library

    During the medieval period saints played a significant role in the religious culture of Western Europe. During the thirteenth century a Dominican monk named Jacobus de Voragine compiled and edited a collection of hagiographies, named the Legenda aurea, or ‘Golden Legend’. The lives of women saints included in this text highlight gender-specific concepts of sanctity. The sanctity of women was constructed in a distinctive way, and saints provided a model for religious women to imitate. Historians have largely ignored both female saints and the Legenda aurea as areas of research, despite the popularity they inspired in medieval society. Certain themes permeate the vitae so frequently that it appears Jacobus intended to promote particular tropes of female sanctity. Saints who were virgins were probably included to appeal to a young female audience, possibly to encourage them to join the fledgling Dominican nunneries. The economic concerns of the order are also highlighted through Jacobus’ emphasis on the saint’s renunciation of wealth, as the Dominicans survived on alms. Noble and widowed saints could have appealed to an older audience of economically autonomous women. By emphasising a return to apostolic types of sanctity Jacobus is promoting his order and safeguarding the economic interests of the Dominicans.

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  • The Sons of Liberty from a Bottom-Up Perspective: Reviewing New Social Scholarship Fifty Years Later

    Leeson, Benjamin James (2015)

    Undergraduate thesis
    University of Canterbury Library

    New social history had a profound effect upon the nature of American historiography. Its bottom-up approach radically challenged the traditional historical narrative, producing a string of dynamic studies throughout the 1960s and 1970s. New social historians increasingly focused their studies on the localised experiences of marginalised groups, heralding in the highly influential cultural turn of the early seventies. Yet despite its resounding significance, scholars have a tendency to brush over the complexities and nuances of new social history. Rather, they simplify the school to a few corresponding traits, thus undermining the multifaceted character of this rich historiographical tradition. This dissertation intends to amend such misconceptions. A number of scholars have attempted to define new social history. Yet the school itself naturally evades precise definition. New social history was both individualistic and pluralistic. As such, any attempt to conceptualise the school renders a result riddled with deficiencies. This dissertation will examine how the new social historians approached a singular historical phenomenon, namely, the Sons of Liberty. By focusing solely on the Sons of Liberty, this dissertation will uncover a profusion of divergent interpretations that not only exemplifies the multifaceted character of new social history, but also enables us to appreciate the rich complexities of this historiographical tradition.

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  • Canterbury – Full Steam Ahead 1863 – 1878 : The History of the Canterbury Provincial Railways

    Cross, Alastair Adrian (2015)

    Undergraduate thesis
    University of Canterbury Library

    This research essay examines and investigates the history of railway transport in New Zealand by utilising the Canterbury Provincial Railways (in operation 1863-1878) as operated by the Canterbury Provincial Government as a case study. The Canterbury Provincial Railways are considered by New Zealand historians and in particular transport historians to be the beginning of the modern-day New Zealand Railways network and the start of the rail-making era of New Zealand History. I consider the role that the Canterbury Provincial Railways have played between 1863 and 1878, and to what extent the railways benefited the region of Canterbury. In addition, the place of other Provincial attempts at railway construction are also briefly considered and their place in New Zealand’s railway history next to that of the Canterbury Provincial Railways. All previous revisions of the Canterbury Provincial Railways’ history have either been to look at it in a regional rail perspective or to solely focus on the railway, but not within the wider context of Canterbury region, which this research essay seeks to do. Overall, this research essay seeks to develop better the understanding of the place the Canterbury Provincial Railways plays in the wider history not only of the Canterbury region but also New Zealand too.

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  • Putaringamotu/Riccarton Bush : from wilderness to native bush reserve

    Morrison, Melissa A (2015)

    Undergraduate thesis
    University of Canterbury Library

    This research essay examines the significance of Putaringamotu/Riccarton Bush to the various facets of Canterbury’s history to which it is connected. Putaringamotu/Riccarton Bush is a place of significance to the history of Canterbury as it helps to tell the story of the environment, Maori and the first pioneers of the Canterbury Plains. This research essay draws upon a number of primary sources, such as legislation and personal correspondence, in order to answer the question of why an area of native bush within the city of Christchurch is still significant and relevant today. The answer to this question lies in the ability of the Bush to tell the story of the Canterbury Plains, and those who have called the area home, from the 1300s until the present day. Putaringamotu/Riccarton Bush is the only remnant of the Kahikatea Swamp forests which once covered the Canterbury Plains and therefore contributes to the environmental history of New Zealand. The Bush also uncovers the cultural and social practices of local Maori before the arrival of the first European settlers. However, the reason that Putaringamotu/Riccarton Bush remains so significant today is because of its connection to the pioneering foundations of Christchurch. The Bush inspired and influenced the Deans brothers, Canterbury’s first successful pioneers, and the Canterbury Association, to choose the Plains as the location of the city of Christchurch. It is highly probable that had the Bush not existed upon the Plains then the city of Christchurch may have been established elsewhere. The current use of Putaringamotu/Riccarton Bush as a conservation area and meeting place ensures that each of these facets of Canterbury’s history are acknowledged and remain relevant and significant within Christchurch today.

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  • Defining the enemy : intellectuals, soldiers and their attitudes towards the rules of engagement.

    Foss, Nicholas William (2015)

    Undergraduate thesis
    University of Canterbury Library

    This dissertation examines the different attitudes of soldiers and intellectuals towards the laws of war and the rules of engagement, with a particular focus on defining the enemy. In the past there has been a focus on the broader theories of the laws of war and how they work on paper. This is why studying the attitudes of soldiers who have firsthand experience of the rules of engagement is useful in understanding the moral issues in war. The general attitudes of intellectuals and soldiers towards the laws of war are first examined, relying on the past historiographical work of Michael Walzer and John Fabian Witt. This is followed by an examination of the moral ambiguities generated by war in a historical context, using specific examples from past conflicts. Soldiers’ autobiographies from the War on Terror are a rich source of analysis They reveal how the rules of engagement imposed by the legislators do not necessarily correspond to the soldiers’ perspective on the battlefield which leaves soldiers vulnerable to charges of murder.

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  • Toxic tabloids toxicology, the press, and the public in nineteenth-century England.

    Easton, Holly (2015)

    Undergraduate thesis
    University of Canterbury Library

    This dissertation examines the way in which the English public in the nineteenth century engaged with criminal toxicology, through the medium of the newspapers. It aims to fill a gap in the historiography of toxicology, by combining the approaches of single-case analysis and statistical analysis to assess public opinion and action. This dissertation argues that the public’s engagement with criminal toxicology occurred through the context in which they encountered it, namely the judicial system. In addition to this, public engagement was built upon an informed understanding of the role of toxicology in the courtroom and was capable of producing tangible change. Through examining four sensational cases of criminal poisoning over the nineteenth century, this dissertation traces the development of the general public’s understanding of toxicology and resulting reactions to it. Throughout the century, the newspapers gradually disseminated more information about trials and the toxicology involved in them to the public, which they were able to act upon, by means of placing pressure on the authorities to reconsider the outcomes of contentious trials and the laws that had contributed to them. Overall, the public engaged increasingly with toxicology through the judicial system, agitating for and successfully creating change, in the interests of ensuring justice was done in individual cases and in the future.

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  • Politicising history : an historiographical analysis of the Sino-Tibetan relationship.

    Smart, Grace (2015)

    Undergraduate thesis
    University of Canterbury Library

    This dissertation compares the historiography of the Sino-Tibetan relationship as written by a number of Chinese, Tibetan and Western historians. The relationship between China and Tibet has been written about extensively, however the highly politicised nature of modern debate has resulted in an inability of historians to reach a consensus regarding the status of Tibet. This dissertation will use the 1950-1951 occupation of Tibet by China as a foundation from which to compare the historiography of the Sino-Tibetan relationship during the Chinese Tang, Yuan, Ming and Qing Dynasties, and during the Republic of China. This dissertation will also discuss which historiographical schools and modes of thought have influenced historians. Tibetan historians have been strongly influenced by modern Tibetan ethnocentric nationalism, and by Western romanticised constructions of Tibet. Chinese historians have been influenced by a combination of traditional Chinese thought and Marxist thought. The hegemony of Western political ideas has also caused Tibetan and Chinese historians to frame their arguments around Western concepts. Western historians attempt to be objective, however tend to agree with the interpretation of Tibetan historians. This is largely due to the influence of the romanticised image of Tibet in the West, which creates the idea that Tibet is a peaceful and traditional place which has been violated by Chinese aggression.

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  • ‘If we never meet again’ : the migration experiences of Emma Barker in nineteenth-century Canterbury.

    Martens, Paulien (2015)

    Undergraduate thesis
    University of Canterbury Library

    Studies of migration from England to New Zealand in the nineteenth century have tended to neglect the stories of women. My study addresses this gap by examining the migration story of Emma Barker and her family, and analysing in what ways family dynamics resulted in a gendered experience of migration. It explores gender in a relational manner by comparing and contrasting Emma’s experiences with those of her husband, Alfred. This study also adds to the historiography of the Western family and illuminates broader issues of marriage, parenthood and migration networks. It is based on a sequence of letters written by the Barker family to their extended family in England and highlights the importance of personal correspondence in writing migration histories. This study argues for more nuanced stories of migration that challenge accounts which emphasise the alienating aspect of migration for women.

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  • Inherent contradictions : English women’s literatures’ depictions of First World War service

    Blakey, Katharine (2015)

    Undergraduate thesis
    University of Canterbury Library

    This dissertation examines the idealisation of middle-class men’s and women’s service during the First World War through the study of five novels written by English women between 1916 and 1918. Historiography on women in the war tends to focus on whether the war represented a “watershed” moment for women’s rights. This dissertation argues that although the war was not a watershed moment, it did create an environment which enabled the contestation of women’s traditional domestic role. Chapter One shows how the novels idealised enlistment as men’s greatest service to the war, reflecting prevalent attitudes within society and reinforcing men’s traditional masculine role. In contrast, Chapter Two shows how women’s service threatened traditional notions of domesticity. Concerns for working-class women’s moral and sexual transgressions influencing middle-class women, underlies the novels promotion of war service’s potential moral benefits. Simultaneously, they emphasise the temporary nature of war service, and women’s eventual return to traditional domesticity. The concurrent idealisation of women’s service and their return to the public sphere shows the war not as a “watershed”, but as an environment which reasserted masculinity and challenged traditional ideas of middle-class women’s domesticity.

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  • Cancer Stem Cells in Squamous Cell Carcinoma of the Oral Tongue

    Baillie, Ranui Francesca (2015)

    Undergraduate thesis
    University of Otago

    Background: Given the discovery of cancer stem cells (CSCs) within haematological and solid tumours and the expression of primitive markers by infantile haemangioma, it was hypothesised that a CSC population would also be present in oral tongue squamous cell carcinoma (OTSCC). A deeper understanding of the cells that drive tumourigenesis is required for the development of mechanism-based therapies for OTSCC. Aims: This study aimed to identify and characterise the CSC population within OTSCC based on their protein and gene expression profiles. Methods: Immunohistochemical staining, Western Blotting, mass spectrometry and Nanostring analysis were employed to investigate the expression of a panel of proteins and genes in formalin-fixed paraffin-embedded tissues, and snap frozen tissues of OTSCC from 21 patients. Markers used include epithelial cancer markers (p63 and EMA), CSC markers (CD44, CD133 and SOX2) and embryonic stem cell (ESC) markers (Oct-4, Nanog and pSTAT3). Results: Widespread and overlapping expression of p63, EMA, CD44, SOX2, pSTAT3, Nanog and Oct-4 was identified within the OTSCC. Co-expression of CD44, SOX2, Oct-4, Nanog and pSTAT3, was found within the OTSCC cells, while cells scattered within the peri-tumoural stroma expressed CD44, CD133, pSTAT3, Nanog and Oct-4. A CD44+/SOX2+/Nanog+/Oct-4+/pSTAT3+ but CD133-/EMA-/p63- CSC population was identified in OTSCC. Expression of CSC and ESC markers by differentiated phenotype structures, and the presence of polyploid giant cancer cells that are CD44+/Nanog+ were novel findings. Conclusions: The unique widespread distribution of the CSC population with co-expression of epithelial cancer cell, CSC and ESC markers within OTSCC suggests that these cells are comprised of several overlapping sub-populations that are organised hierarchically within the tumour. The lack of CD133 expression in OTSCC tumour cells brings into question the utility of this protein as a CSC marker. The findings demonstrate a unique expression signature for the CSC population within the OTSCC samples investigated and support a hierarchical CSC model of carcinogenesis, while the novel findings provide interesting avenues for further research.

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  • The role of retromer in the epithelial sodium channel trafficking pathway

    Geda, Anna Caterina (2015)

    Undergraduate thesis
    University of Otago

    The epithelial sodium channel (ENaC) is a protein located at the apical membrane of polarised epithelial cells, primarily expressed in the epithelia of the gastrointestinal tract, lungs and kidney. ENaC's main function is that of absorbing sodium and it is strongly involved in regulating and maintaining total-body salt and water homeostasis, acting as the rate-limiting step for sodium reabsorption into the body. Its activity, therefore, is crucial for determining blood volume and, as a consequence, blood pressure. The sorting and trafficking of ENaC to the apical membrane is a tightly controlled process, requiring the interaction of multiple proteins and organelles. Although ENaC has been well-characterised, there are certain aspects about its trafficking which need to be clarified, such as defining the many proteins involved in the recycling of the channel to and from the apical membrane. A potential, novel candidate involved in ENaC recycling is the retromer complex. This endosome-associated protein complex has been shown to have a role in protein recycling, as well as maintaining cell polarity by assisting in the transport of proteins to and from their appropriate membrane. The aim of this study was to investigate whether retromer is involved in the recycling of ENaC in polarised epithelia, focusing on three specific proteins, namely ccdc22, Snx4 and KIBRA. Whilst ccdc22 is an established component of the retromer complex, Snx4 and KIBRA were hypothesised to be part of retromer, a plausible concept given their cellular localisation and proposed function. To test whether ccdc22, Snx4 and KIBRA were involved in ENaC recycling, their function was altered (via protein knockdown or overexpression) and the effects on ENaC trafficking were measured. Using transiently transfected HEK293 (human embryonic kidney) and FRT (Fischer rat thyroid) cells, semi-quantitative analysis was carried out with Western blots to visualise whether the knockdowns/overexpression of the proteins of interest were occurring. Then, Ussing chamber experiments were conducted to detect any changes in the ENaC channel’s activity at the apical membrane when a retromer protein was knocked down or over-expressed. Finally, GST-pulldown assays were performed to visualise whether the ENaC channel interacted with retromer through the protein KIBRA. Significant knockdowns were obtained of both Snx4 (ps blood pressure.

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  • Rib Fractures in Infants: Retrospective Survey of Fractures and Biomechanical Study.

    Blackburne, William Bligh (2015)

    Undergraduate thesis
    University of Otago

    Literature suggests that rib fractures are highly associated with abuse and the present understanding is that antero-posterior compression associated with the ‘shaken baby syndrome’ is their cause. However, this mechanism rests on a number of assumptions with little experimental data to support them. Recent work using a porcine model of fractures suggests that, in the case of lateral fractures this may be highly unlikely. This work shows a feasible alternate mechanism, that of blunt force trauma (BFT), for the cause of these lateral fractures. A piglet model is used and shows the ease with which ribs fracture as a result of BFT, compared to the difficulty of fracture seen previously in compressive injury. The initial development of a computational simulation of these ribs for use in injury scenarios is also outlined here. Secondly, skeletal surveys from New Zealand’s largest children’s care facility, Starship Hospital, were examined to give a picture of non-accidental injury (NAI) and how its patterns compare with accidental injury in New Zealand. It has been found that, as in foreign studies, there are a number of lesions highly associated with abuse and these include rib fractures, which are highly specific (97%) for NAI. Unusuallyhigh frequencies of lateral-type rib fractures (46.4%) were found and half the cases were found to be unilateral. This is not wholly in line with the currently accepted idea that rib fracture is due to antero-posterior compression, in which bilateral, posterior fractures are said to be most common. Overall, this work brings into question the traditional mechanism of rib fractures, provides a highly useful snapshot of abusive injury in NZ and also sets a strong foundation for future work.

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