12,115 results for 2000, University of Canterbury Library

  • Social work field educator practice: expanding the vision

    Chilvers, Dominic John (2017)

    Doctoral thesis
    University of Canterbury Library

    Social workers identify experiential learning opportunities as critical components of their education, but in Aotearoa New Zealand there is significant concern due to increasing demand and variable quality in field education. Although training more field educators and establishing professional standards is certainly an important part of addressing these challenges, this study explored the broader contextual factors that impact field educator practice. The research reported in this thesis focused on mediating factors in the professional socialisation and practice of social work field educators, with the objective of exploring how to influence developmental processes. This qualitative enquiry can be located within a constructionist paradigm, informed by critical pragmatism and cultural-historical activity theory. The exploratory descriptive design focused on social work field education in Canterbury, Aotearoa New Zealand. In the first phase, 20 field educators participated in individual interviews and thematic analysis was used to identify a number of key influences on their practice. This initial analysis was then shared with participants in five focus groups to verify the conclusions and identify appropriate professional responses to the issues identified. Further thematic analysis was then undertaken and a model of field education articulated to shape future developments. Analysis of the interviews identified a number of tensions within the field education activity system and between two other dominant systems; professional practice and social work education. Tensions within activity systems indicate potential for transformational change and sites for developmental learning. However, analysis also suggested that power dynamics between practice and education, and the alienation of field educators, create barriers and resistance to change. This is particularly evident in the persistence of monoculturalism in field educator practice. The development of professional learning communities for field educators is proposed, as a response to the challenges currently facing field education in Aotearoa New Zealand.

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  • Developing graduate teacher adaptive expertise: from broad intentions to practice

    Abbiss J; Astall C; Davey R; Fickel LH; Morton M (2015)

    Conference Contributions - Other
    University of Canterbury Library

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  • Ko Au Te Moana, Ko Te Moana Ko Au: Te Rangatiratanga Me Te Kaitiakitanga o Roto i Te Rāngai Kaimoana Māori (I Am The Ocean, The Ocean Is Me: Rangatiratanga And Kaitiakitanga In The Māori Seafood Sector)

    Matthews, Ben (2018)

    Masters thesis
    University of Canterbury Library

    Prior to 1840, rangatira exercised exclusive and unqualified sovereignty over their lands and fisheries within their respective jurisdictions. However, this sovereignty was subsequently taken away from them through colonisation following the signing of the Treaty of Waitangi/Te Tiriti o Waitangi. This has had debilitating flow-on effects on the ability of Māori to exercise rangatiratanga and kaitiakitanga today. To illustrate the challenges facing Māori and iwi in their pursuit of rangatiratanga and kaitiakitanga, this study draws on the case study of the Māori Seafood Sector. Specifically, it investigates the question “what factors inhibit and enhance rangatiratanga and kaitiakitanga in the Māori Seafood Sector (MSS)?” This study finds that the factors inhibiting and enhancing the rangatiratanga of Māori in the MSS generally revolve around sovereignty and the possession and exercise of customary proprietary rights. Furthermore, this study finds that kaitiakitanga generally revolves around the Māori cosmological worldview of the land, ocean and all environment as ancestral beings imbued with mauri. In this sense, Māori are umbilically connected to the environment through whakapapa. This is the foundation through which Māori see their roles as Kaitiaki (guardians) of the environment with the responsibility to nurture and protect its mauri to ensure it is maintained for future generations. This study draws on the ‘inside-out model of transformation’ to analyse the factors inhibiting and enhancing rangatiratanga. The theory suggests Māori focus on Māori needs, aspirations and preferences and challenge their own thinking to circumvent colonisation of the mind. In addition, the theory of ‘relational wisdom’, which focuses on the interconnected relationships within the environment, will be used to analyse the factors that enhance kaitiakitanga while ‘dissociation’, the opposite of relational wisdom, will be used to analyse the factors that inhibit kaitiakitanga. This mixed-method study draws on secondary data analysis and qualitative data collection through semi-structured interviews with a total of fifteen Kaikōrero Māori (Māori interview participants) of varying backgrounds and interests in the MSS.

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  • Experimental investigation of a zeotropic working fluid and working fluid filling factor on system performance in a small-scale ORC

    Wijninckx, Richard (2017)

    Masters thesis
    University of Canterbury Library

    Organic Rankine Cycle (ORC) systems are capable of utilising low-enthalpy heat sources to generate power. For the performance engineering of ORC systems, it is important to understand process parameters and component behaviour. To maximise performance, modelling of the plant thermodynamics must be coupled with data analysis to develop diagnostic procedures, find optimal operating points, and diagnose problems to schedule the most cost effective maintenance. An existing ORC system at the University of Canterbury has been upgraded from a previous iteration to assist in furthering our knowledge of ORC system design and construction. This paper presents experimental results from running a 1 kW ORC system using HFC-M1 refrigerant, a zeotropic mixture of R245fa and R365mfc, as the working fluid under a wide range of operating conditions. Hot exhaust combustion products from a 30kW CapstoneTM Gas Turbine are used as the heat source, and heat is transferred via a thermal oil loop to the working fluid through a plate heat exchanger. A scroll expander magnetically coupled to an AC generator is used for work extraction and energy conversion. Trials focused on testing the full range of performance, and investigated the effect of a zeotropic working fluid, and the influence of varying the working fluid liquid level on system performance. Trials were prematurely ended by bearing failure in the ORC scroll expander. However, analysis of the results from additional tests suggest the working fluid charge in the system influences operation, corroborating findings in literature. While inconclusive, these initial results support the need for further testing the effect of the DVR in a fully functioning system. A comparative study was performed between the system actual performance and the theoretical performance to evaluate the degree of impact of the operational issues on the system performance. The unit was disassembled to evaluate the component compatibility and assess functionality over the operation. It transpired the system mass was not conserved during the operation due to leakage, contributing to the overall deterioration in system performance over time. It is concluded the zeotropic mixture was chemically incompatible with system components leading to system failure. Critiques of components and working fluid, derived from experiences in operating the system, coupled with general trends produced by the results, provide recommendations for the design and testing of future small-scale ORC systems.

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  • The effects of a combination of two receptor tyrosine kinase inhibitors on two ovarian cancer cell lines.

    Al-Hussainni, Wafa Nasser Hassan (2017)

    Doctoral thesis
    University of Canterbury Library

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  • Harmonic state estimation : error analysis and optimal location for power quality measurements.

    Bhujel, Diwakar (2017)

    Doctoral thesis
    University of Canterbury Library

    The harmonic levels in a distribution system are becoming more important as the use of non-linear loads and new technology is increasing. Monitoring of the harmonic levels is important in order to manage them. Direct measurement of harmonics at all locations is too costly, yet obtaining a system-wide view is important. Harmonic State Estimation (HSE) is a cost-effective alternative to direct monitoring of the harmonics. To date, it has been applied mostly to transmission systems but in this work, it is applied to an actual distribution system using actual measurements. The aim of this research is to find out how the measured power quality data can be utilised and used for the efficient and accurate estimation of harmonics by using HSE technique, and installing equipment at optimal locations of power distribution networks. HSE is performed based on a robust mathematical technique, Singular Value Decomposition (SVD). The SVD based HSE algorithm is first validated with the simulation results from the harmonic penetration study on the model of an actual distribution feeder using Open Distribution System Simulator (OpenDSS) and MATLAB. The estimated results and the measured values are compared and found to be extremely close to each other. The validated algorithm is then applied to the actual distribution system. Harmonics are measured at eight locations in one of the feeders of an actual distribution system. Using the measurements and the system model, HSE is performed. The estimates and the actual measurements are compared. Comparison is performed for several scenarios assuming different number of measuring equipment available for taking measurements. The observability of the system is also checked. Locations of the measuring equipment, which can give maximum observability with the least errors in the estimated values, are found. Such locations are taken as the optimal locations for the placement of the measuring equipment. A power quality assessment tool has been developed to evaluate and visualise the power quality indices based on the measurements taken by the power quality monitors in Unison Networks Limited. It has been established that harmonic state estimation using SVD method can be applied to the distribution systems to estimate the harmonics at unmonitored locations using few measurements and the system information. Further, it has been shown how the optimal location of the measuring equipment can be found using the observability of the system and the minimum error in the estimates. A new and simple method of adding new equation to the measurement equation in order to improve observability has also been applied for the non-triplen odd harmonics. This research has thus been successful in providing the experimental evidence for the application of HSE (based on SVD) to the distribution systems for the first time, finding optimal location for the placement of measuring equipment to monitor harmonics, and developing Power Quality Assessment and Visualization Tool for the Power Quality Management System in a distribution company.

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  • Allosteric regulation of 3 deoxy-D-arabino-heptulosonate 7-phosphate synthase.

    Fan, Yifei (2017)

    Doctoral thesis
    University of Canterbury Library

    Allostery refers to the process in which interaction of an effector ligand with one site of the protein changes the function of the protein at a distant site. Despite the critical role of allostery in regulation of metabolic pathways, little is known about the details of the allosteric networks and the remarkable diversity in allosteric mechanisms. This study utilises several examples of allosteric proteins to illustrate the interwoven relationships between various allosteric mechanisms, ranging from large conformational changes to subtle dynamic communications. An important metabolic enzyme, 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAH7PS), was selected for this study due to its unique diversity of allosteric regulations and its important role as the first committed step in aromatic amino acid biosynthesis. Essential in many pathogenic bacteria, however lacking mammalian counterparts, DAH7PS and related pathway enzymes provide opportunities in development of novel antimicrobial drugs. The first part of this study addresses the determinants of allosteric ligand selectivity and potency for DAH7PS enzymes that exhibit large conformational changes, and provides structural and functional insights that contribute to the understanding of the role of conformational change in allostery. The second part of this study addresses interchangeability between two different allosteric mechanisms by demonstrating the ease of gene fusion to link two contemporary protein domains and produce functional chimera. The third part of this study addresses the allosteric regulation in DAH7PS enzymes from a different subfamily, for which no large conformational changes are involved in delivering allosteric communication. The crystal structure of a related chorismate mutase enzyme contributes to the understanding of protein-protein interactions associated with allosteric regulations employed by this type of DAH7PS. The final part of this study addresses the current limitations in studying allosteric systems and explores the advantages of new techniques, including Förster resonance energy transfer and electron paramagnetic resonance, in offering valuable information on the timescales and molecular structures associated with allostery.

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  • Erosion sources and sediment pathways to streams associated with forest harvesting activities in New Zealand.

    Visser R; Brown, K.R. (2017)

    Reports
    University of Canterbury Library

    Streams and rivers are abundant in our plantation forests and the Forest Industry prides itself on protecting the intrinsic values they provide, including clean water and quality aquatic habitat. In ensuring they remain protected, the industry has both legal obligations through Resource Management Act and Regional Council requirements, as well as a professional obligation through Forest Accord agreements and the adoption of the NZFOA Environmental Code of Practice (ECoP). It is well known that forest harvesting, including the development of roads and infrastructure, can compromise these waterway values. With the law being effects-based, a clear focus should be on concentrated flows of runoff and sediment to stream channels (aka ‘breakthroughs’) that are linked to our harvesting practices. Improved knowledge about breakthroughs can be used to prescribe site-specific best management practices (BMPs) to protect water quality and aquatic habitat. To better understand how often breakthroughs occur and to identify and describe the most common breakthrough sources, the stream channels associated with 23 recent commercial forest harvests were surveyed. A breakthrough had to have the following characteristics to be recorded: evidence of scour from surface runoff and/or a concentrated trail (pathway) of sediment that reached the stream channel. Overall, there were 3.4 breakthroughs per kilometre of stream, or one breakthrough for every 6.5 hectares of harvest area, which is almost identical to studies from the Piedmont region of the southeastern United States where they found one breakthrough for every 6 to 8 hectares of harvest area. In this study, ground-based logging was associated with nearly twice as many breakthroughs as cable logging (i.e. 6.2 versus 3.3 breakthroughs per kilometre of stream) due to more soil disturbance from trails near streams. Seventy-three percent of breakthroughs were associated with concentrated runoff from roads, trails, stream crossings, and machine tracks on the hillslope. Road-stream crossing approaches delivered concentrated runoff to stream channels more often if they were associated with log truck roads and/or surface runoff could travel long distances from the adjacent and uphill road segment to the stream. Log truck roads are compact by design to support heavy loads, whereas skid trails often retained some of the protective functions of the forest floor (i.e. higher infiltration capacity). Longer road drainage lengths are associated with greater runoff volumes and velocities, thus increasing the potential for hydrologic connectivity with the stream. Conversely, where skid trail approaches to stream crossings did lead to breakthroughs, potential erosion rates were 44 times higher than those of log truck roads at stream crossings. This finding highlights the importance of closing skid trails properly upon harvest completion, especially at stream crossings. Installation of water bars and turnouts to control surface runoff and application of slash to skid trail approaches can be used to reduce the potential for sediment delivery at road-stream crossings. Overall, the level of protection provided to our waterways post-harvest is good. However, the majority of breakthroughs that were recorded could be directly attributed to operational activities and a more consistent adoption of BMPs, especially in the specific areas identified in this report, would reduce our impact even further. Common characteristics of breakthrough sources can include poor infiltration capacity, large quantities of exposed soil, and steep slopes. This project report provides specific examples (as observed in this study) of forestry practices used to reduce the frequency of sediment breakthroughs and their impacts on water quality and aquatic habitat, such as:  Planning to locate roads away from streams, control road gradient and reduce earthworks Harvest planning to minimise tracking and stream crossings Installation of road drainage structures to control water in small amounts and reduce surface runoff velocity Positioning of road drainage structures to avoid direct or indirect discharges to stream channels Closure of temporary road-stream crossings that includes both water control and provisioning of immediate surface cover.

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  • Optimisation of mutation detection in genes responsible for seed shattering and seed size in perennial ryegrass (Lolium perenne L.)

    Fu, Zeyu (2017)

    Doctoral thesis
    University of Canterbury Library

    Perennial ryegrass (Lolium perenne L.) is one of the most important pasture grasses in New Zealand. However, seed production is negatively impacted by seed shattering (shedding). Recently, genes involved in the shattering process have been isolated and functionally characterised in several crop species, including qSH1 and SH4 in rice and SH1 in sorghum. The aim of this project was to identify the critical genes involved in the seed shattering process in perennial ryegrass, and then to screen for mutations in the target gene in a perennial ryegrass EcoTILLING population. Additionally, seed size is an aspect of seed production of interest to perennial ryegrass breeders. CKX1 has been identified as playing a key role in seed size in rice and wheat, so the LpCKX1 was added as a target gene for mutation screening. DNA sequences of genes involved in seed shattering and seed size in the Poaceae were used to identify and isolate target genes in perennial ryegrass using a comparative genomics strategy. The candidate ryegrass shattering genes were identified using an ‘in-house’ perennial ryegrass transcriptome database. The relative expression levels of candidate ryegrass shattering genes were determined using RT-qPCR during the floret and seed developmental stages. A genetic model for seed shattering in perennial ryegrass is outlined. LpSH1 and LpCKX1 were selected as the target genes for mutation screening in the ryegrass EcoTILLING population, and the full-length DNA sequences of both target genes were amplified. Several methods designed to optimise the EcoTILLING approach were developed. For mutation screening, plant genomic DNA was isolated using regenerated silica columns. The reliability of using regenerated silica columns was tested in terms of both yield and purity. A new method combining high resolution melting (HRM) analysis to detect CEL I digestion products was developed to reduce the time taken for mutation screening. The CEL I+HRM method was tested to screen mutations in exon 1 of LpCKX1, but due to the high degree of genetic diversity in perennial ryegrass and the high GC-content in LpCKX1, this method was not suitable for perennial ryegrass, but could be used for self-pollinated species, such as wheat and pea. A homemade HRM master mix was optimised, and HRM analysis was used to screen for mutations in LpSH1 and LpCKX1 in the EcoTILLING population. Multiple mutations in LpSH1 and LpCKX1 were identified from the EcoTILLING population. These were then sequenced to detect if the mutations were likely to cause a change in protein structure and function. The strategy adopted in this project allowed for the application of genetic knowledge from well-studied domesticated plants to be applied to a lesser-studied crop plant, and shows the potential for detecting useful mutations for future plant breeding.

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  • Interactive visualization of MARS spectral CT datasets

    Mandalika, Veera Bhadra Harish (2017)

    Doctoral thesis
    University of Canterbury Library

    This thesis develops a 3D manipulation approach for MARS spectral CT datasets for medical diagnosis/imaging. The key outcome is the design of a novel 2D/3D hybrid user interface for interactive exploration. A study is presented that shows the effectiveness of the hybrid user interface compared to a standard 2D interface for the novice (medical student) as well as experienced (radiology resident) users in diagnostic radiology. The study demonstrated that the hybrid interface is an effective approach that requires minimal training to achieve consistently accurate results. In fact, using the hybrid interface, the students’ accuracy scores matched that of trained residents. Spectral CT (also referred to as colour CT) is an emerging medical imaging modality that acquires data over multiple x-ray colours in order to provide more accurate images and expand medical applications. The MARS project has developed a small specimen spectral CT scanner for pre-clinical research. This thesis work builds on MARS Vision, an in-house visualisation tool developed for analysing MARS datasets. The first accomplishments in this thesis advance the tools and features in MARS Vision. Some of the main features include stereoscopic 3D rendering, rapid mesh extraction, a rendering engine, and an arbitrary slice view. These features also form a framework to facilitate primary research into 3D manipulation. The thesis presents a hybrid user interface that combines the zSpace stereoscopic display (with 3D stylus input) with a standard 2D display (with mouse and keyboard input). The interface augments the diagnostic radiology workflow by adding a 3D component, as opposed to replacing the existing workflow. This thesis also presents an evaluation of the hybrid interface by comparing it to a standard 2D interface (based on Inteleviewer) along with a 3D only interface. The study involved 21 medical students and 10 radiology residents performing a scoliosis diagnosis task using the three interfaces. It demonstrated that the hybrid interface was an effective alternative for 3D manipulation in medical diagnosis. This interface is implemented in the commercial version of MARS Vision and is currently being used by several pre-clinical research groups worldwide.

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  • Putative auditory-evoked neurophonic measurements using a novel signal processing technique: a pilot case study

    Cook AM; Allsop AJ; O'Beirne GA (2017)

    Journal article
    University of Canterbury Library

    With changes to cochlear implant candidacy and improvements in surgical technique, there is a need for accurate intraoperative assessment of low-frequency hearing thresholds during cochlear implantation. In electrocochleography, onset compound action potentials (CAPs) typically allow estimation of auditory threshold for frequencies above 1 kHz, but they are less accurate at lower frequencies. Auditory nerve neurophonic (ANN) waveforms, on the other hand, may overcome this limitation by allowing phase-locked neural activity to be tracked during a prolonged low-frequency stimulus rather than just at its onset (Henry, 1995). Lichtenhan et al. (2013) have used their auditory nerve overlapped waveform (ANOW) technique to measure these potentials from the round windows of cats and guinea pigs, and reported that in guinea pigs these potentials originate in the cochlear apex for stimuli below 70 dB SPL (Lichtenhan et al., 2014). Human intraoperative round window neurophonic measurements have been reported by Choudhury et al. (2012). We have done the same in hearing impaired awake participants, and present here the results of a pilot study in which we recorded responses evoked by 360, 525, and 725 Hz tone bursts from the cochlear promontory of one participant. We also present a modification to the existing measurement technique which halves recording time, extracting the auditory neurophonic by recording a single averaged waveform, and then subtracting from it a 180◦ group-delayed version of itself, rather than using alternating condensation and rarefaction sound stimuli. We cannot conclude that the waveforms we measured were purely neural responses originating from the apex of the cochlea: as with all neurophonic measurement procedures, the neural responses of interest cannot be separated from higher harmonics of the cochlear microphonic without forward masking, regardless of electrode location, stimuli or post-processing algorithm. In conclusion, the extraction of putative neurophonic waveforms can easily be incorporated into existing electrocochleographic measurement paradigms, but at this stage such measurements should be interpreted with caution.

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  • The construction of social meaning: A matched-guise investigation of the California Vowel Shift

    Villarreal DJ (2016)

    Theses / Dissertations
    University of Canterbury Library

    Research on social meaning, which links language variation to the wider social world, often bases claims about the social meanings of linguistic forms on production (i.e., speakers’ situational use of meaningful forms). In the case of the California Vowel Shift (CVS), an ongoing restructuring of the vowel system of California English that takes place below the level of conscious awareness, previous production research has suggested that the CVS carries social meanings of carefreeness, femininity, and privilege. Left unclear in these production-based claims is whether listeners actually pick up on and recognize the social meanings that speakers apparently utilize the CVS to transmit. In this research, a dialect recognition task with matched guises (California-shifted vs. conservative) forms the basis for exploring Californian listeners’ reactions to the CVS, and how these reactions are mediated by perceptions of dialect geography. In short, this research focuses on listeners’ reactions to the CVS in order to address a more fundamental question: How do listeners and speakers together participate in the construction of social meaning? Stimuli for the main study task were drawn from excerpts of sociolinguistic interviews with 12 lifelong California English speakers from three regions of the state: the San Francisco Bay Area, Lower Central Valley, and Southern California. Guises were created from interview excerpts by modifying the F2 of each TRAP and GOOSE token via source-filter resynthesis methods. Californian guises featured backed TRAP and fronted GOOSE; conservative guises featured fronted TRAP and backed GOOSE. Ninety-seven Californians participated in a perceptual task in which they attempted to identify speakers’ regional origin and rated speakers on affective scales. iii The results indicated that Californians recognize the CVS as Californian, as California-shifted guises were less likely to be identified as from outside California (but more likely to be identified as from Southern California). Listeners rated California-shifted guises higher on the scales Californian, sounds like a Valley girl, and confident, indicating a core of social meanings indexed by the CVS. Among listeners from the San Francisco Bay Area, the CVS indexes masculinity, but among Southern California listeners, the CVS indexes femininity. Listeners from across California also rated speakers who they believed to be from the same region as them higher on Californian, familiar, and sounds like me. This research demonstrates that the social meanings of linguistic forms do not reside only in speakers’ situational use of these forms, as listeners did not associate the CVS with carefreeness, femininity, or privilege, the social meanings of the CVS suggested by previous studies of California English production; instead, I propose an account of the indexical field that links perception and production by placing the core social meanings of the CVS uncovered by this research (Californian identity, sounding like a Valley girl, and confidence) at the center of the CVS’s indexical field. This research also contributes to theory in perceptual dialectology and language change. In order to explain this study’s finding that the CVS is associated with Southern California, this research introduces the perceptual-dialectological process of centrality: the identification of speakers who are believed to most exemplify the speech of a given region. Finally, this research suggests an attitudinal stance that allows changes from below such as the CVS to flourish: speakers are aware of the change in the community (at a tacit level, if not consciously) but do not believe that they are participating in the change.

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  • Ethology and sensory physiology associated with social organisation in yellow-eyed mullet (Aldrichetta forsteri), kahawai (Arripis trutta), and snapper (Chrysophrys auratus).

    Middlemiss, Karen Lewanne (2017)

    Doctoral thesis
    University of Canterbury Library

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  • Atmospheric trace gases support primary production in Antarctic desert surface soil

    Ji M; Greening C; Carere CR; Bay S; Steen J; Montgomery K; Lines T; Beardall J; van Dorst J; Snape I; Stott MB; Hugenholtz P; Ferrari B; Vanwonterghem, Inka (2017)

    Journal article
    University of Canterbury Library

    Cultivation-independent surveys have shown that the desert soils of Antarctica harbour surprisingly rich microbial communities. Given that phototroph abundance varies across these Antarctic soils, an enduring question is what supports life in those communities with low photosynthetic capacity. Here we provide evidence that atmospheric trace gases are the primary energy sources of two Antarctic surface soil communities. We reconstructed 23 draft genomes from metagenomic reads, including genomes from the candidate bacterial phyla WPS-2 and AD3. The dominant community members encoded and expressed high-affinity hydrogenases, carbon monoxide dehydrogenases, and a RuBisCO lineage known to support chemosynthetic carbon fixation6. Soil microcosms aerobically scavenged atmospheric H2 and CO at rates sufficient to sustain their theoretical maintenance energy and mediated substantial levels of chemosynthetic but not photosynthetic CO2 fixation. We propose that atmospheric H2, CO2 and CO provide dependable sources of energy and carbon to support these communities, which suggests that atmospheric energy sources can provide an alternative basis for ecosystem function to solar or geological energy sources. Although more extensive sampling is required to verify whether this process is widespread in terrestrial Antarctica and other oligotrophic habitats, our results provide new understanding of the minimal nutritional requirements for life and open the possibility that atmospheric gases support life on other planets.

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  • Additive Manufacturing of Catalyst Substrates for Steam–Methane Reforming

    Kramer M; McKelvie M; Watson MJ (2017)

    Journal article
    University of Canterbury Library

    Steam–methane reforming is a highly endothermic reaction, which is carried out at temperatures up to 1100 C and pressures up to 3000 kPa, typically with a Ni-based catalyst distributed over a substrate of discrete alumina pellets or beads. Standard pellet geometries (spheres, hollow cylinders) limit the degree of mass transfer between gaseous reactants and catalyst. Further, heat is supplied to the exterior of the reactor wall, and heat transfer is limited due to the nature of point contacts between the reactor wall and the substrate pellets. This limits the degree to which the process can be intensified, as well as limiting the diameter of the reactor wall. Additive manufacturing now gives us the capability to design structures with tailored heat and mass transfer properties, not only within the packed bed of the reactor, but also at the interface between the reactor wall and the packed bed. In this work, the use of additive manufacturing to produce monolithic-structured catalyst substrate models, made from acrylonitrile–butadiene–styrene, with enhanced conductive heat transfer is described. By integrating the reactor wall into the catalyst substrate structure, the effective thermal conductivity increased by 34% from 0.122 to 0.164 W/(m K).

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  • Any Time, Any Place, Flexible Pace: Technology-Enhanced Language Learning in a Teacher Education Programme

    Howard J; Scott A (2017)

    Journal article
    University of Canterbury Library

    Abstract: Ongoing developments in e-learning, improved internet accessibility and increased digital citizenry provide exciting opportunities to integrate effective classroom pedagogies with online educational technologies, creating mixed-mode courses to enhance student engagement and facilitate greater autonomous learning. This research examines pre-service teacher education students’ perceptions of the effectiveness of experiential and digitally-mediated tools which take them beyond the constraints of traditional lecturetype delivery. Quantitative and qualitative results from distance and face-to-face cohorts show the value the students ascribe to tools employed in a modified language course. These are discussed in relation to reported changes in students’ proficiency in the target language and culture, and their teaching confidence, using principles for effective instructed language learning as an interpretive lens. The data provide valuable insights into features that enhanced the students’ digitally-mediated learning experiences in this blended delivery course, including the impact of when, where and how they could engage with course material.

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  • Hard rock tunnel boring machine penetration test as an indicator of chipping process efficiency

    Villeneuve MC (2017)

    Journal article
    University of Canterbury Library

    © 2017 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. The transition from grinding to chipping can be observed in tunnel boring machine (TBM) penetration test data by plotting the penetration rate (distance/revolution) against the net cutter thrust (force per cutter) over the full range of penetration rates in the test. Correlating penetration test data to the geological and geomechanical characteristics of rock masses through which a penetration test is conducted provides the ability to reveal the efficiency of the chipping process in response to changing geological conditions. Penetration test data can also be used to identify stress-induced tunnel face instability. This research shows that the strength of the rock is an important parameter for controlling how much net cutter thrust is required to transition from grinding to chipping. It also shows that the geological characteristics of a rock will determine how efficient chipping occurs once it has begun. In particular, geological characteristics that lead to efficient fracture propagation, such as fabric and mica contents, will lead to efficient chipping. These findings will enable a better correlation between TBM performance and geological conditions for use in TBM design, as a basis for contractual payments where penetration rate dominates the excavation cycle and in further academic investigations into the TBM excavation process.

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  • Robots and racism

    Bartneck C; Yogeeswaran K; Ser QM; Woodward G; Sparrow R; Wang S; Eyssel F (2018)

    Journal article
    University of Canterbury Library

    Most robots currently being sold or developed are either stylized with white material or have a metallic appearance. In this research we used the shooter bias paradigm and several questionnaires to investigate if people automatically identify robots as being racialized, such that we might say that some robots are “White” while others are “Asian”, or “Black”. To do so, we conducted an extended replication of the classic social psychological shooter bias paradigm using robot stimuli to explore whether effects known from humanhuman intergroup experiments would generalize to robots that were racialized as Black and White. Reaction-time based measures revealed that participants demonstrated ‘shooter-bias’ toward both Black people and robot racialized as Black. Participants were also willing to attribute a race to the robots depending on their racialization and demonstrated a high degree of inter-subject agreement when it came to these attributions.

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  • Measurement of patient anxiety in MRI - comparing VR simulation to a questionnaire.

    Figg, Helen (2017)

    Masters thesis
    University of Canterbury Library

    Magnetic resonance imaging (MRI) is a widely used, expensive procedure to obtain detailed images of the human body for diagnosis of many medical conditions. The quality of the images is significantly affected by movement of the patient, with some images even being rendered unsuitable for use. This is important because of the substantial cost involved in use of the scanner and clinical support of the patient. To minimize the risk of anxious movement causing a failed scan, some patients are sedated using medicine, however it may be that this is sometimes unnecessary. Only those who undergo an MRI without sedation first, will know if sedation was required, incurring significant cost. This master thesis project investigates a new low-cost technology option, the use of a fully immersive virtual reality (VR) simulation of the medical procedure itself as a means to estimate patient response. A prototype is developed and tested in a user study, first in the lab with volunteers, and then with MRI hospital staff on site. Once refined, the virtual reality simulation is offered to patients immediately prior to their scheduled MRI scan. Patient anxiety levels are recorded throughout the VR and MRI procedure to gain a clearer understanding of stress profiles of individual patients. The main question is whether VR is useful in predicting anxiety of patients during MRI. Results showed that there was a strong correlation between patient anxiety in VR and in MRI but also, if VR were removed a strong correlation existed between before MRI and during MRI. Both significantly predicted average anxiety during MRI, with VR accounting for 71.4% of anxiety during MRI of which 58.8% could be predicted by using anxiety before any scan. The main effect of exposure showed that there was no statistically significant difference in anxiety level between those who had VR and those who did not. The main effect of stage showed there was no statistically significant difference between anxiety level at the different time points of the scan. Overall anxiety level data showed no statistically significant interaction.

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  • Model-based glycaemic control using subcutaneous insulin for in-patients

    Stewart, Kent (2018)

    Doctoral thesis
    University of Canterbury Library

    Dysregulation of blood glucose (BG) levels can occur due to either the influence of stress hormones and external drugs in the critical care setting or a developed resistance/impairment to glucose regulation as seen in Type 1 and 2 diabetes. In both situations, external intervention to assist in regulating BG levels has shown reductions in morbidity and mortality. A method that has proven effective in the Intensive Care Unit (ICU) is the Stochastic TARgeted (STAR) model-based Glycemic Control (GC) protocol, which uses a combination of population-based stochastic models and Model Predictive Control (MPC) to provide safe and effective GC. Therefore, this type of GC may prove effective for out-patient type 2 diabetics. However, STAR is developed for the ICU setting and more specifically the model used, the Intensive Control Insulin Nutrition Glucose (ICING) model, is developed based on ICU patient characteristics and is not necessarily suitable for the out-patient setting. This research attempts to develop the STAR protocol and associated ICING model for better suitability of out-patient GC. In-silico and clinical data sets are used to review and develop control methodologies and technologies, and their impact on GC and outcomes. In addition, a clinical trial is designed to better understand the metabolic behaviour of type 2 diabetes, and enable improved, safer control of this cohort. The representation and use of the ICING model-based insulin sensitivity (SI ) is investigated and validated in the ICU setting. Linear interpolation of sparse BG measurements was proven to give the best estimate of intermediate BG dynamics (mean RMSE 0.39 mmol/L). Minutely resampling of the interpolated BG measurements is shown to give the best representation of GC performance characteristics when GC protocol’s measurement frequency and sparsity varied. The stochastic model currently used by the STAR controller was shown to represent both the Christchurch, New Zealand (NZ) and Gyula, Hungary ICUs well, with the SI variability being within the controllers current stochastic model bounds consistently equal to or greater than 90% of the time. Piece-wise polynomial approximations of the stochastic models were shown to represent the currently used bounds well (All R2 values > 0.96) and provide approximately equal GC performance (% time in BG band 4.4-8.0 mmol/L, 87.9% vs. 87.5%, P=0.67) and safety (BG measurements < 2.22 mmol/L, 9 vs. 8 measurements, P=1.0) in virtual trials. Continuous 2nd order B-spline basis function (BF) were shown to provide a much more physiologically realistic representation of SI , providing a more realistic fit of point of care (PoC) measurement error compared to the currently used stepwise constant BFs (fitting error variance, 2.4% current zeroth order B-spline BF and 6.0% 2nd order B-spline BF vs. 6.0% published glucometer error). The STAR GC protocol’s clinical data was reviewed and areas of improvement investigated. Clinical data from STAR in Christchurch Hospital ICU, NZ and Kálmán Pándy Hospital ICU, Gyula, Hungary since 2011 was reviewed in terms of GC performance and safety. STAR was shown to provide approximately equally effective GC performance (86.6% and 87.1% time BG 4.4-8.0 mmol/L, respectively) and safety (patients with BG < 2.22 mmol/L, 4/292 Christchurch, and 2/47 Gyula) in both cohorts. These results were confirmed by the high data entry compliance of information entered into the STAR tablets, with the lowest compliance being in the feed related interventions (86.5% enteral nutrition (EN), and 88.2% parenteral nutrition (PN) interventions). STAR was also shown to be able to provide higher or equivalent feed rates than the best unit surveyed in an international survey of 150 ICUs over 20 different countries, while still providing safe and effective GC. Stepped by day feeding protocols were shown to provide a promising alternative to the currently used variable feeding regime used by STAR, significantly reducing workload (19.8% reduction) while maintaining GC performance and safety. A new STAR framework was developed, Stochastic Model Predictive (STOMP) control, that evaluated interventions based on a series of cost functions with longer 6 hour prediction horizon, improving clinical flexibility and allowing for longer 4 hour measurement intervals. All of these outcomes serve to validate and the modelling and control methods for GC in less acute wards and eventually the out-patient setting. The type 2 diabetic and pre-diabetic out-patient was investigated to develop our understanding of their metabolic characteristics. An clinical trial was designed assess the effects of exogenous basal insulin on endogenous insulin production of type 2 diabetic and pre-diabetic out-patients, and collect data related to their metabolic characteristics. The initial results of this trial are presented and the trial logistics discussed. No major concerns of patient discomfort and safety arose from the initial 2 patients. These results are a first step towards addressing type 2 diabetes using model-based basal insulin support early in treatment. Overall, the research performed in this thesis was designed to develop the STAR protocol and associated ICING model for GC of out-patients with pre-diabetes and type 2 diabetes. Linearly interpolation of sparse raw BG measurements allows for more accurate identification of model-based SI and minutely or hourly resampling provides a fairer assessment of GC protocol performance. The stochastic models used by STAR capture patient SI variability well, while being approximately generalizable across independent cohorts, and can be approximated with piece-wise polynomial functions for easier use. A considerably more physiologically realistic representation of the ICING model’s SI was created, better representing BG measurements and the associated error. The developed representation of SI would more optimally interpolate sparse, variable data and could be easily applied to sparser out-patient data. The STAR GC protocol was simplified and made more clinically flexible, while maintaining GC performance and safety, through the introduction of piece-wise polynomial stochastic models, a minimal workload stepped feeding protocol, and cost function control methodology (STOMP). Ultimately, these analyses better validate and incrementally simplify STAR for the out-patient setting. Finally, a clinical trial was designed and implemented to investigate basal insulin therapy for out-patients with pre-diabetes or type 2 diabetes, and develop our understanding of this cohort’s metabolic characteristics.

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