1,477 results for ResearchSpace@Auckland, 2012

  • Response: Social work, science, social impact: Crafting an integrative conversation

    Nurius, SP; Kemp, Susan (2012-09-01)

    Journal article
    The University of Auckland Library

    Shifts in the ways that science is being undertaken and marshaled toward social change argue for a new kind of professional competence. Taking the view that the science of social work is centrally about the relationship of research to social impact, the authors extend Fong???s focus on transdisciplinary and translational approaches to science, illustrating ways that national and international priorities are exerting enormous influence in structures for and expectations of science relevant to social work. The authors also emphasize the growing centrality of transformational research, focusing in particular on the interdependence of education and impact. The intent is to stimulate reflectiveness regarding social work???s preparedness to support and indeed amplify a robust culture of high impact science, including more confident, clearly articulated roles and skills in this contemporary scientific landscape.

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  • When to Start, What to Start and Other Treatment Controversies in Pediatric HIV Infection

    Turkova, A; Webb, Rachel; Lyall, H (2012-12)

    Journal article
    The University of Auckland Library

    Over the last decade there have been dramatic changes in the management of pediatric HIV infection. Whilst observational studies and several randomized control trials (RCTs) have addressed some questions about when to start antiretroviral therapy (ART) in children and what antiretrovirals to start, many others remain unanswered. In infants, early initiation of ART greatly reduces mortality and disease progression. Treatment guidelines now recommend ART in all infants younger than 1 or 2 years of age depending on geographical setting. In children >1 year of age, US, European (Paediatric European Network for Treatment of AIDS; PENTA) and WHO guidelines differ and debate is ongoing. Recent data from an RCT in Thailand in children with moderate immune suppression indicate that it is safe to monitor asymptomatic children closely without initiating ART, although earlier treatment was associated with improved growth. Untreated HIV progression in children aged over 5 years is similar to that in adults, and traditionally adult treatment thresholds are applied. Recent adult observational and modeling studies showed a survival advantage and reduction of age-associated complications with early treatment. The current US guidelines have lowered CD4+ cell count thresholds for ART initiation for children aged >5 years to 500 cells/mm3. Co-infections influence the choice of drugs and the timing of starting ART. Drug interactions, overlapping toxicities and adherence problems secondary to increased pill burden are important issues. Rapid changes in the pharmacokinetics of antiretrovirals in the first years of life, limited pharmacokinetic data in children and genetic variation in metabolism of many antiretrovirals make correct dosing difficult. Adherence should always be addressed prior to starting ART or switching regimens. The initial ART regimen depends on previous exposure, including perinatal administration for prevention of mother to child transmission (PMTCT), adherence, co-infections, drug availability and licensing. A European cohort study in infants indicated that treatment with four drugs produced superior virologic suppression and immune recovery. Protease inhibitor (PI)-based ART has the advantage of a high barrier to viral resistance. A recent RCT conducted in several African countries showed PI-based ART to be advantageous in children aged <3 years compared with nevirapine-based ART irrespective of previous nevirapine exposure. Another trial in older children from resource rich settings showed both regimens were equally effective. Treatment interruption remains a controversial issue in children, but one study in Europe demonstrated no short-term detrimental effects. ART in children is a rapidly evolving area with many new antiretrovirals being developed and undergoing trials. The aim of ART has shifted from avoiding mortality and morbidity to achieving a normal life expectancy and quality of life, minimizing toxicities and preventing early cancers and age-related illnesses.

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  • K-means clustering pre-analysis for fault diagnosis in an aluminium smelting process

    Aini Abd Majid, N; Young, Brent; Taylor, Mark; Chen, John (2012)

    Conference item
    The University of Auckland Library

    Developing a fault detection and diagnosis system of complex processes usually involve large volumes of highly correlated data. In the complex aluminium smelting process, there are difficulties in isolating historical data into different classes of faults for developing a fault diagnostic model. This paper presents a new application of using a data mining tool, k-means clustering in order to determine precisely how data corresponds to different classes of faults in the aluminium smelting process. The results of applying the clustering technique on real data sets show that the boundary of each class of faults can be identified. This means the faulty data can be isolated accurately to enable for the development of a fault diagnostic model that can diagnose faults effectively.

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  • Characterisation of soybean oil droplets formed by the breakup of a laminar capillary liquid jet

    Hoh, ST; Farid, Mohammed; Chen, John (2012)

    Conference item
    The University of Auckland Library

    This work is an effort to model the gas-liquid droplet transesterification reaction to produce biodiesel, specifically to determine the hydrodynamic properties of soybean oil droplets produced by the liquid jet instability method as a model to the droplets produced in the spray reactor of Behzadi and Farid (2009), thus enabling the calculation of mass transfer coefficients. Soybean oil, chosen for this work because it is a typical vegetable oil used for biodiesel manufacture, is heated in a pressure tank and driven through a 0.34 mm diameter orifice using compressed air to produce a capillary liquid jet. The velocity of the emerging liquid jet was calibrated against driving pressures (gauge) between 41.4 to 137.9 kPa. Oil temperatures used were 80, 90 and 100oC. It was found that the liquid jet travels at speeds of 6.2 to 16.2 m/s depending on the driving pressure, with corresponding Reynolds numbers of 280 to 1670, and breaks up into a stream of droplets between 7.6 to 12.0 cm from the orifice opening. The manner in which the laminar jet breaks up into droplets, namely the breakup regime, droplet diameter and breakup length, was examined and observed through high-speed photography. In addition, the effect of having a source of external vibration (20 to 40 Hz) to the liquid jet breakup was also examined.

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  • OpenSolver - An open source add-in to solve linear and integer progammes in Excel

    Mason, Andrew (2012)

    Conference item
    The University of Auckland Library

    OpenSolver is an open source Excel add-in that allows spreadsheet users to solve their LP/IP models using the COIN-OR CBC solver. OpenSolver is largely compatible with the built-in Excel Solver, allowing most existing LP and IP models to be solved without change. However, OpenSolver has none of the size limitations found in Solver, and thus can solve larger models. Further, the CBC solver is often faster than the built-in Solver, and OpenSolver provides novel model construction and on-sheet visualisation capabilities. This paper describes Open- Solver???s development and features. OpenSolver can be downloaded free of charge at http://www.opensolver.org.

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  • International comparison of long term care resident dependency across four countries (1998-2009): A descriptive study

    Boyd, Michal; Bowman, C; Broad, Joanna; Connolly, Martin (2012-12)

    Journal article
    The University of Auckland Library

    Aim:??? To describe an international comparison of dependency of long-term care residents. Methods:??? All Auckland aged care residents were surveyed in 1998 and 2008 using the ???Long-Term Care in Auckland??? instrument. A large provider of residential aged care, Bupa-UK, performed a similar but separate functional survey in 2003, again in 2006 (including UK Residential Nursing Home Association facilities), and in 2009 which included Bupa facilities in Spain, New Zealand and Australia. The survey questionnaires were reconciled and functional impairment rates compared. Results:??? Of almost 90 000 residents, prevalence of dependent mobility ranged from 27 to 47%; chronic confusion, 46 to 75%; and double incontinence, 29 to 49%. Continence trends over time were mixed, chronic confusion increased, and challenging behaviour decreased. Conclusion:??? Overall functional dependency for residents is high and comparable internationally. Available trends over time indicate increasing resident dependency signifying care required for this population is considerable and possibly increasing.

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  • Life and living in advanced age: A cohort ctudy in New Zealand - Te puawaitanga o nga tapuwae kia ora tonu, LILACS NZ: Study protocol

    Hayman, Karen; Kerse, Ngaire; Dyall, Lorna; Kepa, M; Teh, Ruth; Wham, C; Wright-St Clair, V; Wiles, Janine; Keeling, S; Connolly, Martin; Wilkinson, TJ; Moyes, Simon; Broad, Joanna; Jatrana, S (2012)

    Journal article
    The University of Auckland Library

    Background The number of people of advanced age (85 years and older) is increasing and health systems may be challenged by increasing health-related needs. Recent overseas evidence suggests relatively high levels of wellbeing in this group, however little is known about people of advanced age, particularly the indigenous M??ori, in Aotearoa, New Zealand. This paper outlines the methods of the study Life and Living in Advanced Age: A Cohort Study in New Zealand. The study aimed to establish predictors of successful advanced ageing and understand the relative importance of health, frailty, cultural, social & economic factors to successful ageing for M??ori and non-M??ori in New Zealand.

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  • Semi-synthesis of bioactive fluorescent analogues of the cytotoxic marine alkaloid discorhabdin C

    Lam, CFC; Giddens, Anna; Chand, N; Webb, VL; Copp, Brent (2012-04-15)

    Journal article
    The University of Auckland Library

    Semi-synthetic N-13 alkylated analogues of the cytotoxic marine alkaloid discorhabdin C have been found to exhibit cytotoxicity towards tumour cell lines at comparable levels to that of the natural product. Incorporation of an ethylenediamine linker facilitated the synthesis of a variety of fluorophore-labelled probes, of which dansyl analogue 20 exhibited biological activity, providing a tool for mechanism of action and cellular localization studies. An alternative probe design was also exemplified, whereby a bioactive alkyne-terminated analogue (24) was found to undergo Huisgen 1,3-dipolar cycloaddition ???click??? reactions with fluorescent azides, enabling studies directed towards activity-based protein profiling.

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  • The role of fear-avoidance cognitions and behaviors in patients with chronic tinnitus

    Kleinst??uber, Maria; Jasper, K; Schweda, I; Hiller, W; Andersson, G; Weise, C (2012)

    Journal article
    The University of Auckland Library

    The current study investigated the role of fear-avoidance???a concept from chronic pain research???in chronic tinnitus. A self-report measure the ???Tinnitus Fear-Avoidance Cognitions and Behaviors Scale (T-FAS)??? was developed and validated. Furthermore, the role of fear-avoidance behavior as mediator of the relationship between anxiety sensitivity and tinnitus handicap was investigated. From a clinical setting, N = 373 patients with chronic tinnitus completed questionnaires assessing tinnitus handicap (Tinnitus Handicap Inventory), anxiety, depression (Hospital Anxiety and Depression Scale), anxiety sensitivity (Anxiety Sensitivity Index-3), personality factors (Big Five Inventory-10), and fear-avoidance. To analyze the psychometric properties, principal component analysis with parallel component extraction and correlational analyses were used. To examine a possible mediating effect, hierarchical regression analysis was applied. The principal component analysis resulted in a three-factor solution: Fear-avoidance Cognitions, Tinnitus-related Fear-Avoidance Behavior, and Ear-related Fear-Avoidance Behavior. Internal consistency was satisfactory for the total scale and all subscales. High correlations between tinnitus-related handicap scales, depressive and anxiety symptoms, and the T-FAS were found, whereas associations with personality factors were low. Moreover, results indicate a significant partial mediation of fear-avoidance behaviors in the relationship between anxiety sensitivity and the cognitive dimension of tinnitus handicap. Results show that fear-avoidance behavior plays an important role in tinnitus handicap. More attention should be paid to this concept in research and clinical practice of psychotherapy for chronic tinnitus.

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  • Knowledge and the curriculum: Music as a case study in educational futures

    McPhail, Graham (2012)

    Journal article
    The University of Auckland Library

    This paper utilises the three theoretical scenarios or ???educational futures??? developed by Michael Young and Johan Muller as reference points for discussing the curriculum conception approaches observed in a recent doctoral study in music education. In using Young and Muller???s model to move from case specifics to broader understandings of curriculum change I argue that cognisance of the relationship between informal and formal knowledge is a key issue in music education. Because of the growing role of popular music in the classroom (Green, 2008) providing access for students to varied forms of knowledge has become an important aspect of teachers??? work. This work involves making connections between aspects of the everyday informal knowledge that many music students bring to the classroom, and the conceptual knowledge of the discipline. The challenges involved in reframing informal knowledge may be relevant in other curriculum areas, particularly where knowledge content is susceptible to socio-cultural influences.

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  • Mass transfer to droplets formed by the controlled breakup of a cylindrical jet - physical absorption

    Hoh, ST; Farid, Mohammed; Chen, John (2012-05-07)

    Journal article
    The University of Auckland Library

    The derivation of Srinivasan and Aiken (1988) for the mass transfer coefficient of carbon dioxide absorption into water droplets formed by controlled breakup of capillary jet was based on turbulent flow equations. This derivation was re-examined, taking into account the fact that the data used were in fact in the laminar flow regime. An alternative derivation and correlation is presented.

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  • Analysis of smelting cell experimental trial data

    Chen, John; Taylor, Mark (2012-02)

    Journal article
    The University of Auckland Library

    Analysis and discussion are presented for the various schemes that may be used in evaluating results such as the current efficiency (CE) obtained from aluminum smelting cell performance trials. A conventional parametric (requiring normal distribution of data) and a nonparametric (not requiring normal distribution) statistical method are given. The analysis allows the results obtained to be expressed in statistical terms with a known level of significance, thus providing a more scientific basis for the interpretation of the results. A scheme for experimental design that takes into account inherent variations and the use of a nonparametric statistical test which does not stipulate normal distribution of data are both suggested.

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  • From singular to over crowded region: Curriculum change in senior secondary school music in New Zealand

    McPhail, Graham (2012-11)

    Journal article
    The University of Auckland Library

    This paper discusses recent developments in the senior music curriculum in New Zealand. I suggest that school music is in transition from its clearly defined origins to its ???regionalisation??? by new content and knowledge. The concepts of knowledge differentiation and verticality are considered in relation to the subject???s now diverse range of curriculum segments, and I argue that the varied progression requirements of these segments combined with an ???emptying out??? of significant aspects of knowledge within an outcomes-based curriculum presents significant challenges for curriculum construction and pedagogy. Also vying for space within the curriculum are elements of informal music learning. These challenges need to be carefully considered in light of recent social realist critiques which highlight the significance of the relationship between knowledge structures, curriculum, pedagogy and student access to powerful knowledge.

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  • Resistance to extinction and relapse in combined stimulus contexts

    Podlesnik, Christopher; Bai, John; Elliffe, Douglas (2012-09)

    Journal article
    The University of Auckland Library

    Reinforcing an alternative response in the same context as a target response reduces the rate of occurrence but increases the persistence of that target response. Applied researchers who use such techniques to decrease the rate of a target problem behavior risk inadvertently increasing the persistence of the same problem behavior. Behavioral momentum theory asserts that the increased persistence is a function of the alternative reinforcement enhancing the Pavlovian relation between the target stimulus context and reinforcement. A method showing promise for reducing the persistence-enhancing effects of alternative reinforcement is to train the alternative response in a separate stimulus context before combining with the target stimulus in extinction. The present study replicated previous findings using pigeons by showing that combining an "alternative" richer VI schedule (96 reinforcers/hr) with a "target" leaner VI schedule (24 reinforcers/hr) reduced resistance to extinction of target responding compared with concurrent training of the alternative and target responses (totaling 120 reinforcers/hr). We also found less relapse with a reinstatement procedure following extinction with separate-context training, supporting previous findings that training conditions similarly influence both resistance to extinction and relapse. Finally, combining the alternative stimulus context was less disruptive to target responding previously trained in the concurrent schedule, relative to combining with the target response trained alone. Overall, the present findings suggest the technique of combining stimulus contexts associated with alternative responses with those associated with target responses disrupts target responding. Furthermore, the effectiveness of this disruption is a function of training context of reinforcement for target responding, consistent with assertions of behavioral momentum theory.

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  • Gender and literacy issues and research: Placing the spotlight on writing

    Peterson, SS; Parr, Judith (2012-03)

    Journal article
    The University of Auckland Library

    In this introduction to a special issue of the Journal of Writing Research, we review four decades of research, bringing writing to the forefront in conversations devoted to gender and literacy. We identify the impetus for much of the research on gender and writing and situate the four articles in this special issue within three themes: gender patterns in what and how students write, cognitive and socio-cultural factors influencing gender differences in student writing, and attempts to provide alternatives to stereotypical gender patterns in student writing. These interdisciplinary themes, further developed within the four articles, underscore the need to consider gender as a complex social, cognitive and linguistic characteristic of both reading and writing.

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  • A template for change? De-risking the transition to CDIO

    Robinson, K; Friedrich, Heide; Kirkpatrick, Robert; Nicholas, C; Rowe, Gerard (2012)

    Conference item
    The University of Auckland Library

    This paper provides a case study on how an established, mature engineering faculty, with a large population of students can make the successful, high risk, step change transition towards the delivery of CDIO objectives - ???Graduating engineers who can conceive-design-implement-operate complex value-added engineering systems in a modern team-based environment??? [1]. The successful results of the project demonstrated the effectiveness of the Systems Thinking and CDIO approach and endorsed this as the basis for a major change strategy. Not only did it demonstrate the quality of all the students on the course, their potential and commitment to engineering, but it also demonstrated willingness of the faculty to take a risk and to embrace change. The project scenario opened up an otherwise overlooked teaching resource ??? that of practitioner lecturers with many years of experience of implementation and operation of major projects. These skills were essential to the scoping, design, planning and implementation of the project as well as giving the backdrop of best practice from industry. Auckland???s experience of introducing a major step change may be used as a Template for other universities who may wish to follow Auckland???s example. This project shows the value of a hearts and minds approach to change as it brought together students, staff and best practice under a multidisciplinary Systems Thinking and CDIO approach - all united in the interests of reconstructing Christchurch.

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  • The role of crowding in contextual influences on contour integration

    Robol, V; Casco, C; Dakin, Steven (2012-07)

    Journal article
    The University of Auckland Library

    Dakin and Baruch (2009) investigated how context influences contour integration, specifically reporting that nearperpendicular surrounding-elements reduced the exposure-duration observers required to localize and determine the shape of contours (compared to performance with randomly oriented surrounds) while near-parallel surrounds increased this time. Here, we ask if this effect might be a manifestation of visual crowding (the disruptive influence of ''visual clutter'' on object recognition). We first report that the effect generalizes to simple contour-localization (without explicit shape-discrimination) and influences tolerance to orientation jitter in the same way it affects threshold exposure-duration. We next directly examined the role of crowding by quantifying observers' local uncertainty (about the orientation of the elements that comprised our contours), showing that this largely accounts for the effects of context on global contour integration. These findings support the idea that context influences contour integration at a predominantly local stage of processing and that the local effects of crowding eventually influence downstream stages in the cortical processing of visual form.

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  • Number and density discrimination rely on a common metric: Similar psychophysical effects of size, contrast, and divided attention

    Tibber, MS; Greenwood, JA; Dakin, Steven (2012-06)

    Journal article
    The University of Auckland Library

    While observers are adept at judging the density of elements (e.g., in a random-dot image), it has recently been proposed that they also have an independent visual sense of number. To test the independence of number and density discrimination, we examined the effects of manipulating stimulus structure (patch size, element size, contrast, and contrast-polarity) and available attentional resources on both judgments. Five observers made a series of two-alternative, forced-choice discriminations based on the relative numerosity/density of two simultaneously presented patches containing 16???1,024 Gaussian blobs. Mismatches of patch size and element size (across reference and test) led to bias and reduced sensitivity in both tasks, whereas manipulations of contrast and contrast-polarity had varied effects on observers, implying differing strategies. Nonetheless, the effects reported were consistent across density and number judgments, the only exception being when luminance cues were made available. Finally, density and number judgment were similarly impaired by attentional load in a dual-task experiment. These results are consistent with a common underlying metric to density and number judgments, with the caveat that additional cues may be exploited when they are available.

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  • The path to MetalSVM: Shared virtual memory for the SCC

    Lankes, S; Reble, P; Clauss, C; Sinnen, Oliver (2012)

    Conference item
    The University of Auckland Library

    In this paper, we present first successes with building an SCC-related shared virtual memory management system, called MetalSVM, that is implemented using a bare-metal hypervisor, located within a virtualization layer between the SCC's hardware and the operating system. The basic concept is based on a small kernel developed from scratch by the authors: A separate kernel instance runs on each core and together they build the virtualization layer. High performance is reached by the realization of a scalable inter-kernel communication layer for MetalSVM. In this paper we present the employed concepts and technologies. We briefly describe the current state of the developed components and their interactions leading to the realization of a Shared Virtual Memory system on top of our kernels. First performance results of the SVM system are presented in this work.

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  • Bi-linear reductions for the Multiprocessor Scheduling Problem with Communication Delays using Integer Linear Programming

    Venugopalan, Sarad; Sinnen, Oliver (2012)

    Conference item
    The University of Auckland Library

    With computer processors running at speeds closer to their theoretical limit, the recent focus has turned to the use of parallelism in hardware by the use of multicore processors for speedup. However, duplicating processors do not automatically translate to faster task execution. The tasks are to be carefully assigned and scheduled so that their total execution time on the multiple processors is minimal. We propose an optimal Integer Linear Programming formulation for the Multiprocessor Scheduling Problem with Communication Delays (MSPCD). The formulations use an effective method to linearise the bi-linear forms arising out of communication delays and introduce new overlap constraints to ensure that no two tasks running on the same processor overlap in time. The proposed formulation is compared with known ILP formulations that solve the MSPCD problem.

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