130 results for Conference poster, 2000

  • Bacterial Contamination Assessment of Rural Ugandan Drinking Water Sources Using EC 3M TM petrifilms TM

    Pearson, A.L.; Long, V.; Meschke, J.S.; Roberts, M.C.; Mayer, J.D. (2007)

    Conference poster
    University of Canterbury Library

    This study examined bacterial contamination levels from 47drinking water sources(92%were surface sources)from two rural Ugandan villages using EC 3M TM petrifilmsTM incubated for 24 h at 37ºC. E. coli counts in 1ml water samples ranged from 0-120 cfu/ml. Confirmation of presumptive E. coli was performed by transferring colonies onto Blood agar followed by characterization by subculture on selective media and standard biochemical analysis. Selected isolates were verified by sequencing of their 16S rRNA genes. A total of 184 colonies were isolated from petrifilms representing 70%of the water sources and 92% of the isolates were identified to genusl evel (n=169). Only 24%of presumptive E. coli, isolates were confirmed as E. coli (n=40). Additionally 61%of isolates were found to be lactose negative and were confirmed as Salmonella, Yersinia and Proteus (n=103). Purified bacterial isolates from the Ugandan water samples and laboratory strains were replated on new petrifilms at various dilutions to determine the potential for misclassification of colony color or gas production. Upon inoculation of new petrifilms, misclassification of coliforms was observed. While the level of bacterial contamination in the rural Ugandan drinking water sources is not unexpected, isolation of lactose negative bacteria from presumptive E. coli colonies and misclassification of coliforms by the petrifilms was unexpected.

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  • Distributions of gene tree branch lengths under coalescence

    Degnan, J.; Kubatko, L. (2008)

    Conference poster
    University of Canterbury Library

    In Bayesian phylogenetic inference, commonly used prior distributions for branch lengths are the uniform, exponential, and gamma distributions. We derive the exact distributions of branch lengths of gene trees under a fixed species tree using the coalescent model. We find that the distributions of branch lengths depend on both the shape and branch lengths of the species tree, which depend on the population genetic parameters of ancestral population sizes and divergence times. Distributions of branch lengths are formed by mixtures depending on the ancestral populations in which coalescent events occur (coalescent histories). For some sets of moderately short branches, these mixtures can lead to distributions of branch lengths which are not well approximated by uniform, exponential, or gamma distributions, thus suggesting that a prior based on a mixture of distributions might be more appropriate for inferring branch lengths on some gene trees.

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  • A 2 parameter model of lung mechanics to predict volume response and optimise ventilator therapy in ARDS

    Sundaresan, A.; Hann, C.E.; Chase, J.G.; Yuta, T.; Shaw, G.M. (2009)

    Conference poster
    University of Canterbury Library

    A majority of patients admitted to the Intensive Care Unit (ICU) require some form of respiratory support. In the case of Acute Respiratory Distress Syndrome (ARDS), the patient often requires full intervention from a mechanical ventilator. ARDS is also associated with mortality rates as high as 70%. Despite many recent studies on ventilator treatment of the disease, there are no well established methods to determine the optimal Positive End expiratory Pressure (PEEP) ventilator setting for individual patients [1]. A model of fundamental lung mechanics is developed based on capturing the recruitment status of lung units. The model produces good correlation with clinical data, and is clinically applicable due to the minimal number of patient specific parameters to identify. The ability to use this identified patient specific model to optimize ventilator management and lung volume recruitment is demonstrated. It thus provides a platform for continuous monitoring of lung unit recruitment and capability for a patient.

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  • The application of system dynamics in power generation planning

    Jalal, T.S.; Bodger, P. (2009)

    Conference poster
    University of Canterbury Library

    Background & Introduction: The introduction of power markets in the electric supply industries (ESI) has called for a different approach to system planning and expansion. The traditional monopolistic vertically integrated system has been replaced by competing companies in the generation and retail sectors. Some of the effects on the generation planning process are: Uncertainties are increased since a department that coordinates a national planning ceases to exist Companies are no longer obligated to have generation surplus as the ESI become profit oriented Limited information is disclosed by competing companies, creating imperfect foresight on investments Non-technical factors such as market conditions, economics and social aspects are becoming more significant in building new power plants Based on these impacts, it is difficult for the power generators to decide when to invest in new power plants. Each country has its own unique environment that makes it difficult to simply adopt measures done in other countries. Hence, this study proposes to study the impact of deregulation on power generation capacity growth in New Zealand investigate suitable national policies that will ensure the reliability of the industry

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  • Rescuing concatenation with maximum likelihood using supermatrix rooted triples

    DeGiorgio, M.; Degnan, J.H. (2009)

    Conference poster
    University of Canterbury Library

    Concatenated alignments are often used to infer species-level reslationships. Previous studies have shown that analysis of concatenated alignments using maximum likelihood (ML) can produce misleading results. We develop a polynomial-time method that constructs a species tree through inferred rooted triples from concatenated alignments. We call this method SuperMatrix Rooted Triple (SMRT). We show that SMRT performs well in simulations and then show that it is a statistically consistent estimator of a clocklike species tree under a binary substitution model as well as other assumptions. SMRT is therefore a computationally efficient and statistically consistent estimator of species trees.

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  • Breath Ammonia Reduction Ratio (ARR) Measures Dialysis Efficacy

    Endre, Z.; Moorhead, K.; Storer, M.; Hu, W-P.; Dean, J.; Logan, K.; Allardyce, R.; Ledingham, K.; McGregor, D.; Senthilmohan, S.; Lee, D.; Scotter, J.; Chase, J.G. (2007)

    Conference poster
    University of Canterbury Library

    Contemporary evidence supports the centuries old notion that expired breath and the headspaces above body fluids and products can serve as biomarkers of organ function. Clinical responsiveness to alterations in clinical status or therapy is dependent upon timely, accurate, relevant physiological data. Current measures of urea and creatinine to assess renal urea reduction are invasive and cannot be repeated frequently or reported quickly enough to define individual response to treatment in real time. In contrast, breath analysis is minimally invasive and can provide real time information about low molecular weight volatile organic compounds (VOCs) such as ammonia1,2.

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  • An Ultra-Cheap Grid Connected Inverter for Small Scale Grid Connection

    Ghimire, P.; Wood, A.R. (2008)

    Conference poster
    University of Canterbury Library

    This paper reports on the development of a cheap and simple grid connected inverters. It is intended for an integration of a small power photo-voltaic or wind turbine to a grid at low cost. The proposed inverter uses the single cycle control technique, which reduces switching complexity and forces the current waveform to match the voltage waveform. The control circuit operation for unity power factor output is explained. The method is simulated on PSCAD program for single phase system. The simulation output exhibits excellent performance with few components. The paper only considers the current wave-shaping control of the inverters and does not discuss other aspects of control such as maximum power point tracking. The simulations are compared with the prototype waveforms.

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  • Estimating Uncertainty in Wildlife Population Estimates

    Brown, J.A.; McDonald, L.; Robinson, T. (2008)

    Conference poster
    University of Canterbury Library

    Estimating an index of animal population size from simple counts can be very challenging. If indices are to be compared among years to assess trend there must be some consistency in what fraction of the population the index is measuring. Variation in population indices among years may be due to variation in the size of the population but it may also be due to variation in counting procedure, in animal detection and, for migratory and foraging animals, in the proportion of the total population available to be counted. We discuss two case-studies of animal counts where we attempt to quantify this extra variation, or uncertainty, using Monte Carlo simulation. In the first case-study we assess uncertainty in penguin population indices from counts, and in the second, we assess uncertainty in migratory bird counts from braided rivers in New Zealand.

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  • Improving the Calculation of Fix-Rate Bias in Automated Telemetry Systems

    Brown, J.A.; Reale, M.; Hodge, M. (2009)

    Conference poster
    University of Canterbury Library

    GPS and other radio tracking equipment are becoming more widely used by researchers for modelling animal habitat. In a typical monitoring program an animal will be fitted with a tracking collar. This tracking collar will fix the animal's location at a set time interval. These fixes of the animal's location can then be cross referenced on a digital map (GIS) containing habitat information and the animal's preferred habitat can be modelled. Care must be used in modelling the habitat because radio tracking collars have different transmission probabilities in different habitats. The habitat observations are biased towards habitats that allow good transmission. One way to minimise this bias is to weight observations by a measure of transmission quality. Researchers have attempted to estimate the detection weighting by placing stationary collars in the study area and recording the fix-rate. The results of these studies are unsatisfactory because stationary collars do not account for animal movement and behaviour. Johnson (1998) used a surrogate for stationary collars by analysing 6 hour time periods where the animal was relatively stationary. We will develop this method further by incorporating the non-stationary sites in the detection rate calculation.

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  • Perception of music for adult cochlear implant users: A questionnaire

    Looi, V.; She, J. (2007)

    Conference poster
    University of Canterbury Library

    Postlingually deafened adult cochlear implant (CI) users often find music to be less pleasant and less enjoyable postimplantation, and a music training program may help to enhance their appreciation of music. However existing studies do not provide detailed information from CI users on the factors which they feel contribute to their poorer ratings for music, nor do they investigate the approach a music training program should take. The purpose of this study was to develop and administer a questionnaire that collects unique information which would assist in the development of a training program aimed at improving CI users’ music perception and appreciation.

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  • Development of a monosyllabic adaptive speech test for the identification of central auditory processing disorder

    O'Beirne, G.A.; McGaffin, A.J. (2009)

    Conference poster
    University of Canterbury Library

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  • Clinical and economic predictors of quality of life in dementia

    Gallrach, F.; Kirk, R.; Hornblow, A.; Croucher, M. (2009)

    Conference poster
    University of Canterbury Library

    • To date, multivariate analyses of quality of life (QoL) in dementia are relatively rare (Banerjee et.al_2009). This study aimed to measure QoL of persons with dementia and their family-caregivers. • The study also examined what interventions from primary and secondary care in New Zealand are helpful for enhancing QoL and what these interventions cost.

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  • Impacts of transport: encouraging potential cyclists

    Taylor, K.; Kingham, S.; Koorey, Glen (2009)

    Conference poster
    University of Canterbury Library

    This poster presents research on impacts of sustainable transport, particularly encouraging commuter cycling. The study focused on issues perceived by potential commuter cyclists, a group underrepresented in transport research.

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  • Environmental Sound Perception of Cochlear Implant Users

    Looi, V.; Arnephy, J.; O'Beirne, G.A. (2007)

    Conference poster
    University of Canterbury Library

    Introduction Most current adult cochlear implant (CI) users achieve higher open-set speech perception scores post- surgery than pre- surgery, a factor which greatly improves their overall quality of life. There is little published research assessing the ability of CI users to identify environmental sounds, an important skill which also impacts upon a patient’s quality of life. This study compared adult CI users to normally hearing (NH) listeners in their ability to identify various environmental sounds. The Environmental Sounds Perception Test (ESPT) developed for this study was more difficult and more comprehensive than those used in current studies, in order to reduce the likelihood of any potential ceiling effect affecting the results. It was hypothesised that the CI users would score lower than similarly-aged NH listeners on the ESPT.

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  • More Sketchy, More AR, More Fun!

    Haller, M.; Landerl, F.; Billinghurst, M. (2005)

    Conference poster
    University of Canterbury Library

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  • ComposAR: An Intuitive Tool for Authoring AR Applications

    Seichter, H.; Looser, J.; Billinghurst, M. (2008)

    Conference poster
    University of Canterbury Library

    This paper introduces ComposAR, a tool to allow a wide audience to author AR and MR applications. It is unique in that it supports both visual programming and interpretive scripting, and an immediate mode for runtime testing. ComposAR is written in Python which means the user interface and runtime behavior can be easily customized and third-party modules can be incorporated into the authoring environment. We describe the design philosophy and the resulting user interface, lessons learned and directions for future research.

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  • Nitrogen dioxide exposure inside and outside of primary schools

    Holland, K.; Kingham, S. (2008)

    Conference poster
    University of Canterbury Library

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  • Augmented Assembly using a Mobile Phone

    Hakkarainen, M.; Billinghurst, M.; Woodward, C. (2008)

    Conference poster
    University of Canterbury Library

    We present a mobile phone based augmented reality (AR) assembly system that enable users to view complex models on their mobile phones. It is based on a client-server architecture, where complex model information is located on a PC, and a mobile phone with the camera is used as a thin client access device to this information. With this system users are able to see an AR view that provides step by step guidance for a real world assembly task. We also present results from a pilot user study evaluating the system, showing that people felt the interface was intuitive and very helpful in supporting the assembly task.

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  • Presence in Video-mediated Communication: Does being there help to come together?

    Hauber, J.; Regenbrecht, H.; Billinghurst, M.; Teoh, H. (2006)

    Conference poster
    University of Canterbury Library

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  • Clinical Data Validation of an improved, physiologically relevant Critical Care Glycaemic Control Model

    Pretty, C.G.; Parente, J.; Razak, N.; Lin, J.; LeCompte, A.J.; Shaw, G.M.; Hann, C.E.; Chase, J.G. (2008)

    Conference poster
    University of Canterbury Library

    Introduction: Stress induced hyperglycaemia is prevalent in critical care. Tight glycaemic control is associated with significantly improved clinical outcomes. Providing tight control is difficult due to evolving patient condition and drug therapies. Model-based/derived methods (e.g. SPRINT) have shown significant mortality reductions. This research validates an improved metabolic control model and its parameters based on predictive capability for use in real-time glycaemic control.

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