41 results for Conference poster, 2011

  • The suitability of iPhone recordings for the acoustic measures of speech and voice quality

    Lin, E.; Hornibrook, J. (2011)

    Conference poster
    University of Canterbury Library

    This study examined the quality of iPhone recordings for acoustic measurements of speech and voice quality. A selection of acoustic measures were extracted from voice samples recorded using the “voice memo” application in an iPhone and compared with those derived from signals directly digitized (DD) in a laptop via a 12-bit A/D converter. Participants were 11 healthy adults, including six females and five males, aged between 27 to 67 years (Mean = 41.8 years, SD = 16.7). The participant was asked to read the first six sentences of the “rainbow passage”. In addition, two participants were asked to produce sustained vowels (/i/, /a/, and /u/) and a sentence (“We saw two cars”) ten times. The simultaneously recorded iPhone and DD signals were analysed to derive 10 acoustic measures, including spectral tilt for the whole sentence and fundamental frequency (F0), percent jitter, percent shimmer, signal-to-noise ratio, amplitude of the first harmonic relative to that of the second harmonic, singing power ratio, and frequencies of the first and second formants (F1 and F2), and vowel space area for the vowel segment. A series of Pearson’s correlation procedures revealed that measures from iPhone and DD signals were highly correlated. Findings of the vowel effect on the experimental measures obtained from iPhone signals were consistent with those from DD signals. However, the mean normalized absolute differences between measures from iPhone and DD signals are optimal (i.e., lower than 20%) only for F0, F1, and F2. These findings suggest that iPhone recordings are as adequate as other types of high quality digital recordings for acoustic measurements of voice quality but most voice measures from different digital recording systems are not directly comparable.

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  • Library services without a library: post-earthquake use of virtual reference at University of Canterbury

    Roberts, S.F.; Fitchett, D.J.; Paterson, M.E. (2011)

    Conference poster
    University of Canterbury Library

    Following the September 2010 earthquake and the closure of a number of campus libraries, library staff at the University of Canterbury was forced to rethink how they connected with their users. The established virtual reference service now meant library staff could be contacted regardless of their physical location. After the February earthquake, with University library closures ranging from 3 weeks to indefinite, this service came into its own as a vital communication tool. It facilitated contact between the library and both students and academics, as well as proving invaluable as a means for library staff to locate and communicate with each other. Transcripts from our post-earthquake interactions with users were analyzed using NVivo and will be presented in poster format showing the increase in usage of the service following the earthquakes, who used the service most, and the numbers and types of questions received. Our virtual reference tool was well used in the difficult post-earthquake periods and we can see this usage continuing as university life returns to normal.

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  • Generation of Micro-Droplets for the Study of Droplet Coalescence and Self-propulsion

    Nock, V.; Sellier, M.; Alkaisi, M.M, Verdier, C. (2011)

    Conference poster
    University of Canterbury Library

    Microfluidic devices play an ever increasing role in nano- and biotechnologies. An example of the recent breakthrough allowed by such technologies is the Lab-on-a- Chip (LOC), which enables orders of magnitude downsizing of assay equipment. An emerging area of research in this technology-driven field is digital microfluidics based upon the micromanipulation of discrete droplets. Microfluidic processing is performed on unit-sized packets of fluid which are transported, stored, mixed, reacted, or analysed in a discrete manner. Possible applications include on-chip assays, polymerase chain reaction, or DNA sequencing.

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  • Acoustic and perceptual evaluation of the quality of radio-transmitted speech

    Kirtikar, S.; Lin, E.; Robb, M.P. (2011)

    Conference poster
    University of Canterbury Library

    When speech signals are transmitted via radio, the process of transmission may add noise to the signal of interest (Biddulph, 1994; Coleman, 2004). This study aims to examine the effect of radio transmission on the quality of speech signals transmitted using a combined acoustic and perceptual approach.

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  • Strong ground motions observed in the 22 February 2011 Christchurch earthquake

    Bradley, B.A.; Cubrinovski, M. (2011)

    Conference poster
    University of Canterbury Library

    Poster listed as B-055

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  • The Effectiveness of Traffic Calming Pinch-Points

    Chai, C.; Nicholson, A.; Koorey, Glen (2011)

    Conference poster
    University of Canterbury Library

    Research investigated the effect of roadway widths for street narrowings or "pinch-points" in Christchurch, with a particular focus on speed and yielding behaviour. A 6m wide 2-way pinch-point was found to be not effective in slowing most private vehicles down. Drivers travelled at a similar speed whether they were crossing the pinch-point by themselves or with opposing traffic approaching. Approximately 40% of drivers reduced their vehicle speed when negotiating a 5m wide 2-way pinch-point. Around 20% of drivers avoided traversing with oncoming traffic and opted to wait until it was clear before proceeding. Male drivers also tended to travel faster through the narrowing when compared to female drivers. For a 4.5m wide 1-way pinch-point where motor vehicles and cyclists approached them simultaneously, one of them gave way and waited nearly60% of the time. Around 35% of the time cyclists and motorists shared the narrowing and 8% of the cyclists (mostly younger children) avoided the narrowing, using a bypass instead. It is recommended that further research be conducted: 1. at more sites with different road widths and environment; 2. with heavy vehicle movements on these pinch-points; 3. to understand whether a longer pinch-point will alter driver behaviour.

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  • Earthquakes, Trees, and the 'New Normal'

    Morgenroth, J. (2011)

    Conference poster
    University of Canterbury Library

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  • The impact of breathiness on the intelligibility of speech

    Thompson, L.; Lin, E.; Robb, M.P. (2011)

    Conference poster
    University of Canterbury Library

    The aim of this study is to determine how deterioration of voice quality, such as breathiness, may impact on the intelligibility of speech. Acoustic analysis was conducted on sustained vowel phonation as well as discrete segments taken from recorded sentences, retrieved from a database of voice disordered speakers. Measures included: frequency of the first two formants (F1, F2), singing power ratio, the amplitude difference between the first two harmonics (H1-H2 amplitude difference), voice onset time, and energy ratio between consonant and vowel (CV ratio). A series of two-way (glottal closure x vowel) repeated measures Analysis of Variances conducted on these acoustic measures showed a significant glottal closure (complete vs. incomplete) or glottal closure by vowel interaction effect for the F2 frequency, H1-H2 amplitude difference, and singing power ratio. Based on findings in literature that reported a dominant first harmonic as a useful predictor of breathiness, the measure of H1-H2 amplitude difference was selected as a factor for investigation of the impact of voice quality on the perception of vowel intelligibility and clarity. Fixed-length vowel segments at five levels of H1-H2 amplitude difference were presented to 10 male and 10 female inexperienced listeners between the ages of 19 and 34 years. It was expected that the tokens with a dominant first harmonic, indicative of a more breathy voice, would be associated with a lower rate of correct vowel identification and a lower rate of being perceived as “clearer”. The finding of a change of the perceptual ratings as a function of the H1-H2 amplitude difference will demonstrate the effect of voice quality on vowel intelligibility.

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  • The potential of Shimokitazawa's open Public Spaces for the production of - creative, innovative, and participated - local culture oriented city making

    Dionisio, M.R.; Ota, H.; De Souza, M.C. (2011)

    Conference poster
    University of Canterbury Library

    The contemporary urban paradigm has started to focus the capabilities of urban communities to support, participate in, and develop creative Regeneration methods that promote the integration of local socio-cultural features, along with the competitiveness and attractiveness of cities, in the international panorama (Pratt, 2010). The purpose of this research is to dissertate the importance of Public Spaces for the success of urban regeneration trends that integrate cultural features, and simultaneously, contribute for the promotion of local identiy and creative public engagement. Considering the scarcity of open space per citizen in Tokyo, in comparison to other cities, Tokyo VOID is a research project (Rahmann, H. - The University of Melbourne; Jonas, M. - RMIT University) that focuses the importance of promoting flexible public uses in temporary vacant spaces, towards the reinforcement of sustainable principles in the city’s open spaces network (Rahmann and Jonas, 2010).

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  • Statistical distributions of particle number concentrations observed in urban transport microenvironments during commuting

    Longley, I.; Shrestha, K.; Kingham, S.; Salmond, J.; Pattinson, W. (2011)

    Conference poster
    University of Canterbury Library

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  • Pregnancy Associated Changes in Insulin Signalling in Daughters of Adolescent Ewes

    Oliver, Mark; Hancock, SN; Kenyon, PR; Blair, HT; Pain, S; Morris, S; Phua, Hui; Bloomfield, Francis (2011-09)

    Conference poster
    The University of Auckland Library

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  • CUTE: CUTting Edge Diamond Optimization

    Downward, Anthony; Zakeri, G (2011)

    Conference poster
    The University of Auckland Library

    The Centenary Diamond, weighing 55g, was estimated to be worth $100 million when it was unveiled in 1991. This diamond was cut from a rough-stone weighing 120g; thus when cutting such a stone, it is imperative to orient the stone such that waste is minimized. Our interactive software allows a user to maximize the value of a diamond from a given rough-stone. As the user alters the orientation of the diamond, it solves optimization problems to scale and position the diamond within the rough-stone.

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  • Impact of PCV7 on antibiotic susceptibiity of nasophayngeal Streptococcus pneumoniae in South Auckland children

    Sekikawa, E; Trenholme, A; Taylor, S; Lennon, Diana; McBride, C; Best, Emma (2011-03-17)

    Conference poster
    The University of Auckland Library

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  • Context and relationship: defining resilience in health social workers

    Adamson, Carole; Beddoe, Elizabeth; Huggard, Peter (2011-11-05)

    Conference poster
    The University of Auckland Library

    A qualitative study of social workers in physical and mental health asked experienced social workers who self-defined as resilient to define the concept and to explore the elements of resiliency within their practice. Initial definition of resilience as a personal characteristic was developed into a strongly contextual and relational construct, the binding feature of which was self-awareness and the capacity to reflect. A strong feature of the social workers??? understanding of resilience was their focus on relationship with colleagues and the quality of professional social work practice with service users. Further reflexive and structural elements in their professional lives were identified, highlighting that resilience within health social workers is in dynamic relationship with the organisational context. A resilience framework derived from current literature and from the research is presented.

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  • Delayed Cerebral Post-arteriole Dilation is Consistent with Observations at Multiple Spatial and Temporal Scales: Evidence from Mathematical Modelling

    Barrett, MJP; Tawhai, MH; Suresh, Vinod (2011-05-25)

    Conference poster
    The University of Auckland Library

    Background and aims: Observations from different neurovascular imaging modalities provide conflicting evidence about the presence and/or extent of volume changes in post-arteriole blood vessels. At the level of individual vessels, two-photon imaging during functional activation shows a rapid increase in arteriolar diameter, but little or no increase in capillaries or venules 1 . In contrast, 'bulk' measurements of flow-volume relationships show large increases in arterial volume 2 , and smaller - but still significant - increases in venous volume 3 . Here, we reconcile these competing observations using a dynamic, biophysically based mathematical model of the hemodynamic response. Methods: We use the widely known Windkessel model that represents blood flow as analogous to electrical current, and networks of blood vessels as analogous to electrical resistances and capacitances. The model also includes a novel description of vascular compliance, viscoelastic effects, and stimulus-driven vasodilation. Experimental observations at progressively more detailed scales are used to constrain and validate the model, following a 'top down' approach. In addition, we test the assumption that post-arteriole vessels do not dilate, and use the model to predict observations at progressively more aggregated scales, following a 'bottom up' approach. Results: Model predictions of the total, arterial, and venous steady state flow-volume relationships agree well with experimental observations, as do predictions of transient changes in flow and volume during functional activation. The model also predicts rapid arteriole dilation during activation. Interestingly, this is accompanied by slow increases in capillary and venule diameter that - for brief stimulation - are near indistinguishable from baseline noise. When assuming no dilation of capillaries or venules, there are only minor differences between the model predictions at the single vessel scale. However, predictions at more aggregated scales are qualitatively and quantitatively different from experimental observations. Conclusions: The model presented here is able to reproduce the main features of experimental observations over a range of spatial and temporal scales. These results suggest that arterial dilation represents the majority of regional cerebral blood volume increases during functional activation, especially during brief stimulation. However, passive dilation in capillaries and venules may be increasingly significant during extended stimulation. This is an important consideration when interpreting or comparing results from neurovascular imaging modalities, such as optical methods and magnetic resonance imaging.

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  • Test- retest reliability of an instrumented elastometer for measuring passive stiffness of the levator ani muscle

    Kruger, Jennifer; Nielsen, Poul; Dietz, HP; Taberner, Andrew (2011-08-31)

    Conference poster
    The University of Auckland Library

    Hypothesis / aims of study Clinical evidence demonstrates strong associations between vaginal birth, the incidence of levator ani (LA) muscle injury, and a decrease in muscle function (1). Imaging modalities such as ultrasound and magnetic resonance imaging have provided insight into the nature of LA injury, confirming that it is significantly implicated in the development of pelvic organ prolapse (2). Strain of the LA muscles during delivery of the fetal head is considerable, and childbirth related trauma to the muscle has been shown to occur in 10-30% of women delivering vaginally (1,2). Thus, developing measures to identify a-priori, those who are most likely to suffer from injury during vaginal birth should be a high research priority. The inherent elasticity of the muscle clearly plays a role in the ability of the muscle to accommodate the fetal head. However, measuring passive stiffness of the muscle in vivo remains challenging. The aim of this study was to further develop and test a novel elastometer (3), designed to estimate in vivo passive stiffness produced by the puborectalis component of the LA muscle, where it passes in close contact with the lateral walls of the vagina, from its origin on the pubic ramus. Study design, materials and methods The elastometer used in this study is a more sophisticated version of a previously developed first-generation device (3). The current version of this instrument (Figure 1) boasts enhanced aesthetics and patient friendliness compared to our previous device. Notably, our elastometer can now implement user-defined measurement protocols under automatic computer control in order to measure the force-displacement characteristics of the LA muscle. The device consists of a hand-piece comprising two aluminium arms, with detachable acetyl plastic speculum ends, actuated by a DC servo mechanism via a load cell. A load cell amplifier and displacement transducer are integrated into the hand-piece, providing force and speculum separation measurements. The hand-piece is connected to a control box that communicates with a laptop computer via a USB connection. The control box contains a data-acquisition device (USB-6009, National Instruments), motor drive circuit, and battery-based power supply. A custom MSWindows application implements a closed-loop motor control algorithm on the laptop, records measurements of speculum displacement and force, and provides feedback to the user. The laptop user-interface displays speculum separation and force on a strip chart, together with a force-displacement graph. The design of the speculum end of the elastometer is such that the tip is wider than the neck, (26mm compared to 18mm) to reduce the likelihood of perineal muscles confounding measurement of passive stiffness. Magnetic clips attach the speculum ends to the device which allows for easy cleaning, and provides the facility of attaching speculums of various sizes. Reliability and repeatability of the elastometer was assessed in 12 volunteers. None of the participants had had vaginal surgery, or any contraindications for vaginal examination. All participants were tested twice, 3 to 5 days apart using the same protocol. The speculum was inserted to the level of the puborectalis muscle (2-4 cm from the introitus) orientated in the coronal plane. After initial familiarisation with the device in situ, recording of the data commenced. All participants were encouraged to remain relaxed during the experiment. Data acquisition was automated with the device opening in 20 stepwise increments, to the desired separation, over 60 seconds. Data were collected at a frequency of 100 Hz. Averaged data over a three second period gave 21 data points per test. The procedure was repeated three times, with the initial run being considered as a preconditioning step and not used for data analysis. Statistical analysis was carried out using ???R??? version 2.12.2 (Copyright (C) 2011 The R Foundation for Statistical Computing). Results from Day 1 were compared with the re-test results using Bland/Altman repeated measures to determine any bias and limits of agreement and Intraclass correlation co-efficient (ICC) to determine reliability across tests and Days. Results The mean age of the 12 participants was 44.3 years (range 26 to 58 years), BMI 26 kg/m2 (range 20.4 to 33.7 kg/m2). Two of these were nulliparous, with the median number of vaginal delivery being 2. Data was visualised in graphic form for each subject across all tests for both days. A representative plot from one subject is shown in Figure 2. ICC???s for the second and third tests respectively were 0.92 (CI 0.89- 0.93), and 0.86 (CI 0.82-0.89). Limits of agreement (from repeated measures Bland Altman) were -2.79 N to +2.31 N, with a mean difference of -0.21 N. Interpretation of results Repeated Bland Altman demonstrates minimal bias with the mean difference close to zero at -0.12 N. The 95% limits of agreement range was slightly over 4 N, and likely to be due to biological variability. The high Intraclass correlation co-efficient for both tests between Days indicate minimal variability of the measurements. Concluding message This second generation elastometer has proved reliable and consistent in the measurement of passive stiffness of the puborectalis muscle in this group of volunteers. These results confirm satisfactory performance of the instrument in preparation for future studies validating this method in clinical and research settings. References 1. DeLancey JO. The hidden epidemic of pelvic floor dysfunction: achievable goals for improved prevention and treatment. Am J Obstet Gynecol. 2005 May;192(5):1488-95. 2. Dietz HP, Simpson JM. Levator trauma is associated with pelvic organ prolapse. BJOG. 2008 Jul;115(8):979-84. 3. Kruger J, et al.. Pelvic floor muscle compliance in Elite nulliparous Athletes. 38th Annual meeting of the International Continence Society. Cario 2008

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  • Mechanisms Of Differences In Ventilation Distribution In The Upright, Supine, And Prone Postures

    Tawhai, Merryn; Hedges, Kerry (2011-05-13)

    Conference poster
    The University of Auckland Library

    Rationale: Measurements of ventilation distribution using various imaging modalities have suggested that the distribution of ventilation in the supine and prone postures is less evidently gravitational than when the lung is upright, and with some studies showing little difference between ventilation distributions in the prone and supine lung. This is despite the concurrent observations of a significant gradient in tissue density when supine, and a typically smaller - or absent - tissue density gradient prone. In this study we use a computational model of lung tissue elasticity coupled to air-flow to study the relationship between posture, density distribution, and ventilation. Methods: An imaging-based geometric model of the lung and airway tree that was developed in a separate study was used here. Flow in the airways was simulated using a one-dimensional fluid dynamics model that includes flow-dependent airway resistance and coupling to tissue elasticity at the airway walls and at the acini. A finite deformation elasticity model was used to predict the effect of gravity on tissue deformation, and the non-linear elasticity of each acinar tissue unit during simulated breathing. The upright lung volume was defined from pulmonary function testing; the supine and prone volumes were assumed to be the same, and equal to the supine air volume as calculated from the subject's computed tomography imaging acquired at FRC. Tissue density and ventilation at each of the ~32,000 distributed acini in the model were averaged within iso-gravitational slices of 10 mm thickness. Results: The gradient of tissue density predicted by the model was markedly larger in supine than in upright or prone. Ratios of the maximum to minimum slice density were 1.95, 1.51, and 1.39 for supine, prone, and upright, respectively. Ventilation in the upright model increased on average towards the dependent tissue, whereas ventilation in supine and prone was decreased in the most dependent and non-dependent regions. The ratios of maximum to minimum slice ventilation were 1.09, 1.03, and 1.31 for supine, prone, and upright, respectively. Conclusions: A lack of gravitational distribution of ventilation in the supine and prone postures compared with upright is predicted on the basis of the smaller size of the horizontal lung and a shift of the dependent tissue to a less-compliant region of the sigmoidal pressure-volume curve at its lower asymptote. This is the same mechanism that results in early filling of the non-dependent tissue when inhaling from residual volume.

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  • Nonlinear dynamics of an electronic model of one-way coupling in one and two dimensions

    Doud, AB; Breen, Barbara; Grimm, JR; Tanasse, AH; Tanasse, SJ; Lindner, JF; Maxted, K (2011-03-21)

    Conference poster
    The University of Auckland Library

    One-way or unidirectional coupling is a striking example of how topological considerations -- the parity of an array of multistable elements combined with periodic boundary conditions -- can qualitatively influence dynamics. Here we introduce a simple electronic model of one-way coupling in one and two dimensions and experimentally compare it to an improved mechanical model and an ideal mathematical model. In two dimensions, computation and experiment reveal richer one-way coupling phenomenology: in media where two-way coupling would dissipate all excitations, one-way coupling enables soliton-like waves to propagate in different directions with different speeds.

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  • Probing Student Approaches and Engagement in Learning Chemistry at University.

    Salter, David; Simpson, MC; Hamilton, R (2011-06)

    Conference poster
    The University of Auckland Library

    This project aims to identify students??? learning approaches, engagement, attitudes and success in chemistry classes that are service-taught as part of a specified health sciences programme and in chemistry classes that are taught as part of a chemistry major programme. It seeks to determine whether any differences exist in the learning approaches, motivational orientation and engagement, and compare the success of a cohort of students who are required to enrol in a compulsory chemistry course as part of a health sciences degree with that of a cohort of students who choose to enrol in a chemistry course with the possible intention of majoring in chemistry. It is intended that both cognitive and motivational individual difference variables are identified and relationships between students??? goal orientation and university academic success evaluated.

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  • Diabetes Management by Primary Health Care Nurses in Auckland, New Zealand

    Daly, Barbara; Arroll, B; Sheridan, N; Kenealy, T; Scragg, R (2011-11-04)

    Conference poster
    The University of Auckland Library

    Methods PHC nurses in Auckland (a 26% random sample) were asked to complete postal and telephone questionnaires (86% response rate), on education, experience, knowledge and diabetes management practice, and to log their care given to diabetes patients on a randomly selected day (n=265). Results Responses were received from 287 PHC nurses (86% response rate) comprising 210 practice nurses (PN), 49 district nurses (DN) and 28 specialist nurses (SNs). Most nurses (96%) were able to identify excess body weight as a major risk factor for type 2 diabetes and elevated blood glucose levels (BGLs) or glycosylated haemoglobin (HbA1c) (86%) for diabetes-related complications. In contrast, CV risk factors were less well identified, particularly smoking, although more by SNs (43%) than PNs (14%) and DNs (12%, p=0.0005). CV complications, especially stroke, were less well known than microvascular complications, and by significantly fewer PNs (13%) and DNs (8%) than SNs (36%, p=0.002). Stronger associations were found between nurse???s knowledge of elevated HbA1c as a risk factor for diabetes-related complications and management activities related to BGLs and medication, compared with knowledge of CV risk factors, which was not associated with assessment of blood pressure or knowledge of patient???s total cholesterol or smoking status. The median number of patients consulted on the randomly selected day was one by 38% of PNs, two by 47% of DNs and 4-5 by 57% of SNs. Overall, PNs consulted almost 60% of the patients sampled, while patients consulted by DNs were older and more likely to be European New Zealanders, tobacco uses and have diabetes-related complications and co-morbidities, while SNs consulted by Maori and Pacific patients. Conclusion: There is a need for PHC nurses to increase their knowledge of CV risk factors with more effective management required and particularly of smoking.

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