5,619 results for Conference item

  • Integration of single-cell microfluidic cell culture with mass spectrometry

    Wlodkowic, Donald; Wright, BEW; Green, M; Akagi, J; Greenwood, D; Villas-Boas, SVB; Williams, DEW (2011)

    Conference item
    The University of Auckland Library

    Microfluidic systems can be constructed on the same scale as single cells, w ith features in the range of 1-100 μm, and with high spatial and temporal control of culture conditions. [1] High-resolution mass spectrometry is the premier tool for the study of proteomics and metabolomics. [2] Integrating the two will enable the evaluation of the physiology of single cells in prescribed culture conditions, leading to advances in research on single cell variability, and the effect of culture conditions, localised environment and perturbations. Toward this end, we have developed integrated microfluidic systems capable of capturing and housing the culture of a single cell using polydimethysiloxane (PDMS) based microfluidics (Figure 1A) and integrated them w ith novel monolithic PDMS electrospray ionisation (ESI) emitters (Figure 1B). [3] We have characterised the fully integrated cell traps/ESI emitters using both test solutions and in trial runs on cells using a Thermo LTQ-FT (hybrid ion trap / Fourier transform ion cyclotron resonance) mass spectrometer (Figure 1C). Initial results on the microfluidic cell traps, microfluidic-ESI characteristics, and performance of the integrated cell traps/ESI system will be presented along with a comparison with conventional nanospray- ESI w ith the integrated microfluidic system w ith emphasis placed on detection sensitivity and interference effects from PDMS.

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  • Dynamic Analysis of Tumour Cell Death Using Dielectrophoresis

    Wlodkowic, Donald; Khoshmanesh, KK; Akagi, JA; Nahavandi, SN; Skommer, JS; Baratchi, SB; Cooper, JMC; Kalantar-Zadeh, KKZ; Williams, DEW (2011)

    Conference item
    The University of Auckland Library

    The important discovery that induction of programmed cell death in neoplastic cells is a critical event that defines tumour growth rate and response to anti-cancer therapy has provided a framework for the rationally designed, molecular anti-cancer therapeutics. The regulation of cancer cell death involves the circuitry of feedback events and rapid switches between analogue and digital responses. Such enormous complexity, with numerous variables acting at the same time, requires multiparametric and dynamic analysis at a single cell level. The opportunity to dynamically quantify individual cellular states is advantageous over the commonly employed static, end-point assays. We describe here the development and application of a microfabricated, dielectrophoretic (DEP) cell immobilisation platform for the real-time analysis of tumour cell death. We applied this technology to the dynamic analysis of haematopoietic tumour cells that represent a particular challenge for real-time imaging due to their dislodgement during image acquisition. The present study was designed to provide a comprehensive mechanistic rationale for accelerated cell-based assays on DEP chips using real-time labelling with cell permeability markers. Results indicate that simple DEP cell immobilisation technology can be readily applied for the dynamic analysis of investigational drugs in hematopoietic cancer cells.

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  • The Boyce-Codd-Heath normal form for SQL

    Ferrarotti, F; Hartmann, S; Koehler, H; Link, Sebastian; Vincent, MW (2011-04-28)

    Conference item
    The University of Auckland Library

    In the relational model of data the Boyce-Codd-Heath normal form, commonly just known as Boyce-Codd normal form, guarantees the elimination of data redundancy in terms of functional dependencies. For efficient means of data processing the industry standard SQL permits partial data and duplicate rows of data to occur in database systems. Consequently, the combined class of uniqueness constraints and functional dependencies is more expressive than the class of functional dependencies itself. Hence, the Boyce-Codd-Heath normal form is not suitable for SQL databases. We characterize the associated implication problem of the combined class in the presence of NOT NULL constraints axiomatically, algorithmically and logically. Based on these results we are able to establish a suitable normal form for SQL.

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  • On the role of the complementation rule for data dependencies over incomplete relations

    Ferrarotti, F; Hartmann, S; Link, Sebastian (2010-07-02)

    Conference item
    The University of Auckland Library

    Recently, an axiomatization for functional dependencies (FDs) and multivalued dependencies (MVDs) has been established where arbitrary attributes can be specified as NOT NULL. That is, the information stored over such attributes must not be incomplete. The axiomatization subsumes previous axiomatizations of FDs and MVDs where every attribute is declared to be NOT NULL, and where no attribute is declared to be NOT NULL. We establish axiomatizations which underpin formally the intuition that the complementation rule is a mere means of database normalization. The results unburden the existing theory of the strong assumption that all attributes are known at the time when the dependencies are specified. The findings extend and unify previous results for the special cases above.

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  • The Media and 25 Years of Children and Computers

    Sheehan, Robert (2009)

    Conference item
    The University of Auckland Library

    This short paper examines how the use of computers by children has been represented in the news media over the last 25 years. Assuming the news media presents the interests and concerns of parents, teachers and children this information can show how well developers of hardware and software for children have met these interests. The examination over such a long period also shows interesting patterns. Things which were once thought of as crucial have lost their importance and discussion has now moved to the effects of the Web in the social lives of children. Over 100 articles from The New York Times were analysed and several interesting themes were extracted both from particular periods of time and from the whole range.

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  • Efficient inference control for open relational queries

    Biskup, J; Hartmann, S; Link, Sebastian; Lochner, JH (2010-08-24)

    Conference item
    The University of Auckland Library

    We present a control mechanism for preserving confidentiality in relational databases under open queries. This mechanism is based on a reduction of costly inference control to efficient access control that has recently been developed for closed database queries. Our approach guarantees that secrets being declared in form of a confidentiality policy are not disclosed to database users even if they utilize their a priori knowledge to draw inferences. It turns out that there is no straightforward transition from the approach for closed queries to open queries. We show, however, that hiding the confidentiality policy from database users is sufficient to preserve confidentiality. Moreover, we propose an algorithmic implementation of the control mechanism.

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  • Solving multi-objective traffic assignment

    Raith, Andrea; Wang, JYT; Ehrgott, Matthias; Mitchell, SA (2013)

    Conference item
    The University of Auckland Library

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  • Promoting the semantic capability of XML keys

    Ferrarotti, F; Hartmann, S; Link, Sebastian; Wang, J (2010-09-15)

    Conference item
    The University of Auckland Library

    Keys for XML data trees can uniquely identify nodes based on the data values on some of their subnodes, either in the entire tree or relatively to some selected subtrees. Such keys have an impact on several XML applications. A challenge is to identify expressive classes of keys with good computational properties. In this paper, we propose such a new class of keys. In comparison to previous work, the new class of XML keys is defined using a more expressive navigational path language that allows the specification of single-label wildcards. This provides designers with an enhanced ability to capture properties of XML data that are significant for the application at hand. We establish a sound and complete set of inference rules that characterizes all keys that are implicit in the explicit specification of XML keys. Furthermore, we establish an efficient algorithm for deciding XML key implication.

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  • Biobjective Air Traffic Flow Management

    Kuhn, K; Raith, Andrea (2010)

    Conference item
    The University of Auckland Library

    Air traffic flow management seeks to extenuate delay created by congestion in the air traffic control system while ensuring equitable access to air transportation system resources. Mathematical programming formulations of the air traffic flow management problem typically minimize delay costs, ignoring evidence that equity is a critical concern in practice. Recently, authors have adjusted classical formulations, adding terms to the objective function to penalize various results deemed unfair. This work reformulates the air traffic flow management problem as a formal multiobjective optimization problem. We are able to find all Pareto-optimal solutions trading off effciency and equity, without having to select and parameterize a model of the costs of inequity.

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  • Hippocratic databases: extending current transaction processing approaches to satisfy the limited retention principle

    Kirchberg, M; Link, Sebastian (2010-01)

    Conference item
    The University of Auckland Library

    The concept of Hippocratic Database Systems has been introduced by Agrawal et al. Based on international privacy legislation, ten privacy principles have been identified that an information system should meet in order to enforce privacy and data protection properties. Among those, the limited retention principle and its challenges to traditional database algorithms are considered in this paper. In particular, we examine how data records cannot merely be deleted from the database but also how their corresponding log records may be erased from the log (without violating the necessity to retain data recoverability properties). To the best of our knowledge, there exists no current transaction processing or data recovery approach that supports the deletion of data from log entries as desired by Hippocratic Database Systems.

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  • Parallel Solutions of the Navier-Stokes Equations on a CM5

    Norris, Stuart; de Vahl Davis, G; Leonardi, E (1996)

    Conference item
    The University of Auckland Library

    A Finite Volume Navier-Stokes solver has been written using Fortran 90 on a CM5 parallel computer. The program is written in the data-parallel paradigm, using the array syntax of Fortran 90 to express the parallelism of the algorithm. This has allowed a portable code to be written, which will run on both parallel and serial computers.

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  • Even the Food has Character: Animation, Food and Metaphor in Ratatouille (3,500 words)

    Allen, Brenda (2010)

    Conference item
    The University of Auckland Library

    Ratatouille (dir Brad Bird, 2007) is one of a few fully animated films included in lists of 'foodie' films. One critic declares that 'Even the food has character'. But aspects of the film trouble a straightforward reading of haute cuisine as art and of the chef as artist. In this paper I read Ratatouille not just as a discussion on art, as many have already done, but as offering layer of subtext where cuisine acts as a metaphor enabling a complex discussion of the state and status of movie animation in relation to artistic canons and to the imperatives of the movie industry.

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  • How a modest fideism may constrain theistic commitments: Exploring an alternative to classical theism

    Bishop, John (2007-12)

    Conference item
    The University of Auckland Library

    On the assumption that theistic religious commitment takes place in the face of evidential ambiguity, the question arises under what conditions it is permissible to make a doxastic venture beyond one's evidence in favour of a religious proposition. In this paper I explore the implications for orthodox theistic commitment of adopting, in answer to that question, a modest, moral coherentist, fideism. This extended Jamesian fideism crucially requires positive ethical evaluation of both the motivation and content of religious doxastic ventures. I suggest that, even though the existence of horrendous evil does not resolve evidential ambiguity in favour of atheism, there are reasonable value commitments that would preclude those who hold them from satisfying extended Jamesian fideist conditions for committing themselves to classical theism. I then begin a discussion of a possible revisionary theistic alternative (in the Christian tradition) which - one might hope - may meet those conditions. An earlier, shorter, version of this paper was delivered as a keynote address at the APA Pacific 2007 Mini-Conference on Models of God.

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  • Biblical servant, authentic and incarnational leadership: A multilevel model

    Webster, Michael (2011)

    Conference item
    The University of Auckland Library

    This workshop will present the attributes and values that comprise biblical servant, authentic and incarnational leadership and examine how these attributes and values are behaviourally expressed. While authentic leadership is ‘being true to the person you were created to be’ (George, 2003, p.14), incarnational leadership rests ‘on a worldview incorporating kenosis [Philippians 2:7 ‘but made himself of no reputation’], love, and justice’ (Wallace, 2007, p.iii). The workshop will engage with participants in examining how these leadership models might be applied to multiple levels in the school community, from board to syndicate leader.

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  • Sustainability means something clean and tidy, doesn't it?: Developing and assessing children's conceptual understanding of sustainability

    Birdsall, Sally (2006)

    Conference item
    The University of Auckland Library

    The aim of this research was to investigate if New Zealand students aged between 11–12 years of age could develop their understanding of the concept of sustainability through engagement in an environmental education programme set in the context of a local lake.

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  • If you don't listen to the teacher , you won't know what to do: Voice of Pasifika learners

    Perger, Pamela (2007)

    Conference item
    The University of Auckland Library

    This paper reporst on one aspect of a study that explored Pasifika students' ideas about learning mathematics at Year 7. Students were asked to name key practices for learning mathematics (espoused theory) and were then observed working during a regular mathematical class to identify practices they used (theory-in-use). Further discussion enabled the differences between students' espoused theory and their theory-in-use to be explored and evaluated. What it is these students consider 'best practice' in learning mathematics? Do they practice what they preach?

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  • Wanted - One Great Maths Teacher

    Perger, Pamela (2008)

    Conference item
    The University of Auckland Library

    What makes an effective mathematics teacher? Research has identified a number of attributes but most of these are noted from an adults, point of view. What is it that the students consider essential in an effective mathematics teacher? Here a picture of the ideal mathematics teacher as described by a group of 11-12 year old students is presented. The attributes they identified fell into two categories, one addressing factors associated with personal attributes of the teacher and the second factors relating to the learning environment the students saw as most supportive to their mathematical learning.

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  • Eradicating house mice from islands: successes, failures and the way forward

    MacKay, Jamie; Russell, James; Murphy, EC (2007)

    Conference item
    The University of Auckland Library

    The house mouse (Mus musculus) has been spread throughout the world by the actions of humans. It causes severe impacts to native ecosystems, especially in areas where there are no native mammals. It is possible to eradicate mice from islands but they are harder to eradicate than rats. A review of reported eradication attempts found that 17 attempts on 45 islands worldwide failed; a failure rate of 38%. The effect of operational factors on eradication success was examined, but no significant model was formed. Brodifacoum is the most widely used toxicant and has a 49% success rate. Mouse eradications should be attempted wherever possible and recommendations to help increase the success of a house mouse eradication attempt are given.

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  • Author Index

    (2010-10)

    Conference item
    The University of Auckland Library

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  • Cloud-based Contextually Aware Adaptive Systems for Enterprise Transformation

    Peko, Gabrielle; Dong, Ching-Shen; Rohde, Max; Sundaram, David (2012)

    Conference item
    The University of Auckland Library

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