2,247 research outputs found

    Assessing the impact of rail investment on housing prices in north-west Sydney

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    Rail investments alter the accessibility and amenity of residential properties, and thus affect housing prices and overall affordability. This project investigates the impact of the Epping-Chatswood rail link in North-west Sydney on home prices, testing out alternative methodologies for estimating price impacts through spatial analysis of historical property sales data obtained from the RP Data Australia. The paper focuses on one station, comparing price trends before and after the construction of the rail link was announced in 2002, and before and after the opening of the rail line in early 2009. The paper concludes with an assessment of the usefulness of alternative methodologies

    BZ-MC-BP Model for Jet Production from Black Hole Accretion Disc

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    Three energy mechanisms invoking large-scale magnetic fields are incorporated in a model to interpret jet production in black hole (BH) systems, i.e., the Blandford-Znajek (BZ), the magnetic coupling (MC) and Blandford-Payne (BP) processes. These energy mechanisms can coexist in BH accretion disc based on the magnetic field configurations constrained by the screw instability, provided that the BH spin and the power-law index indicating the variation of the magnetic field at an accretion disc are greater than some critical values. In this model the jets are driven by the BZ process in the Poynting flux regime and by the BP process in the hydromagnetic regime, being consistent with the spine/sheath jet structure observed in BH sources of stellar and supermassive size.Comment: 9 pages, 6 figures, accepted by MNRA

    A Selberg integral for the Lie algebra A_n

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    A new q-binomial theorem for Macdonald polynomials is employed to prove an A_n analogue of the celebrated Selberg integral. This confirms the g=A_n case of a conjecture by Mukhin and Varchenko concerning the existence of a Selberg integral for every simple Lie algebra g.Comment: 32 page

    p-species integrable reaction-diffusion processes

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    We consider a process in which there are p-species of particles, i.e. A_1,A_2,...,A_p, on an infinite one-dimensional lattice. Each particle AiA_i can diffuse to its right neighboring site with rate DiD_i, if this site is not already occupied. Also they have the exchange interaction A_j+A_i --> A_i+A_j with rate rij.r_{ij}. We study the range of parameters (interactions) for which the model is integrable. The wavefunctions of this multi--parameter family of integrable models are found. We also extend the 2--species model to the case in which the particles are able to diffuse to their right or left neighboring sites.Comment: 16 pages, LaTe

    Traces, tiles and fleeting moments: art and the temporalities of geomedia

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    This chapter looks at the ways artists working with geomedia technologies have exposed and exploited the complex temporalities of digital mapping, dealing first with the trace of movement in locative media art practices of the early to mid 2000s, and secondly with the appropriation of remote sensing imagery and Street View imagery by artists. The aim is to challenge the idea that geomedia's only temporal effects are ones of timelessness; crucial to this challenge is a separation out of two different versions of timelessness that are often ascribed to cartography and new media respectively, and sometimes conflated. I argue that the stress on atemporality effects in studies of the aesthetics and cultural impact of geomedia, and the conflation of the cartographic and technological/cultural versions of timelessness in particular, moves too quickly to read a surfeit of temporal markers as a collapse of temporality as such

    Moving bodies and the map: relational and absolute conceptions of space in GPS based art

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    Geographers and social scientists have argued that geospatial technologies are contributing to new understandings of space as relational and of cartography as processual and performative rather than representational. There is a fundamental tension in the fact that these new understandings of space and cartography are facilitated by a technology that epitomises an absolute conception of space. The GPS trace has been employed in new media art practices since the early 1990s, and is particularly evident in the locative media genre that emerged in the early 2000s. This article deals with the use of GPS by artists, and the role of art in producing these new understandings of space. The mapped trace of movement has been identified as an inadequate capture of spatial practices. This position –influentially articulated by Michel de Certeau – is associated with a tradition of thought that privileges time as the dimension of dynamism and denigrates space as the dimension of stasis and fixity. This denigrated space is the absolute space of cartography as it has been traditionally understood. This article uses GPS-based artworks to explore different relational understandings of space in which movement is primary, drawing on the work of Tim Ingold, Bruno Latour and Nigel Thrift. By looking at the ways in which media artists have addressed or exploited the tension between the absolute spatiality of cartography and the relational spatiality of movement in their work, it seeks to find a way past seeing these different conceptions of space in such starkly oppositional terms

    <i>In situ</i> laser manipulation of root tissues in transparent soil

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    Aims: Laser micromanipulation such as dissection or optical trapping enables remote physical modification of the activity of tissues, cells and organelles. To date, applications of laser manipulation to plant roots grown in soil have been limited. Here, we show laser manipulation can be applied in situ when plant roots are grown in transparent soil.Methods: We have developed a Q-switched laser manipulation and imaging instrument to perform controlled dissection of roots and to study light-induced root growth responses. We performed a detailed characterisation of the properties of the cutting beams through the soil, studying dissection and optical ablation. Furthermore, we also studied the use of low light doses to control the root elongation rate of lettuce seedlings (Lactuca sativa) in air, agar, gel and transparent soil.Results: We show that whilst soil inhomogeneities affect the thickness and circularity of the beam, those distortions are not inherently limiting. The ability to induce changes in root elongation or complete dissection of microscopic regions of the root is robust to substrate heterogeneity and microscopy set up and is maintained following the limited distortions induced by the transparent soil environment.Conclusions: Our findings show that controlled in situ laser dissection of root tissues is possible with a simple and low-cost optical set-up. We also show that, in the absence of dissection, a reduced laser light power density can provide reversible control of root growth, achieving a precise “point and shoot” method for root manipulation.</p

    Phenotypic and molecular assessment of seven patients with 6p25 deletion syndrome: Relevance to ocular dysgenesis and hearing impairment

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    BACKGROUND: Thirty-nine patients have been described with deletions involving chromosome 6p25. However, relatively few of these deletions have had molecular characterization. Common phenotypes of 6p25 deletion syndrome patients include hydrocephalus, hearing loss, and ocular, craniofacial, skeletal, cardiac, and renal malformations. Molecular characterization of deletions can identify genes that are responsible for these phenotypes. METHODS: We report the clinical phenotype of seven patients with terminal deletions of chromosome 6p25 and compare them to previously reported patients. Molecular characterization of the deletions was performed using polymorphic marker analysis to determine the extents of the deletions in these seven 6p25 deletion syndrome patients. RESULTS: Our results, and previous data, show that ocular dysgenesis and hearing impairment are the two most highly penetrant phenotypes of the 6p25 deletion syndrome. While deletion of the forkhead box C1 gene (FOXC1) probably underlies the ocular dysgenesis, no gene in this region is known to be involved in hearing impairment. CONCLUSIONS: Ocular dysgenesis and hearing impairment are the two most common phenotypes of 6p25 deletion syndrome. We conclude that a locus for dominant hearing loss is present at 6p25 and that this locus is restricted to a region distal to D6S1617. Molecular characterization of more 6p25 deletion patients will aid in refinement of this locus and the identification of a gene involved in dominant hearing loss

    The Hubbard model within the equations of motion approach

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    The Hubbard model has a special role in Condensed Matter Theory as it is considered as the simplest Hamiltonian model one can write in order to describe anomalous physical properties of some class of real materials. Unfortunately, this model is not exactly solved except for some limits and therefore one should resort to analytical methods, like the Equations of Motion Approach, or to numerical techniques in order to attain a description of its relevant features in the whole range of physical parameters (interaction, filling and temperature). In this manuscript, the Composite Operator Method, which exploits the above mentioned analytical technique, is presented and systematically applied in order to get information about the behavior of all relevant properties of the model (local, thermodynamic, single- and two- particle ones) in comparison with many other analytical techniques, the above cited known limits and numerical simulations. Within this approach, the Hubbard model is shown to be also capable to describe some anomalous behaviors of the cuprate superconductors.Comment: 232 pages, more than 300 figures, more than 500 reference

    The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III

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    The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly alpha forest, and a radial velocity search for planets around ~8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes five-band imaging of roughly 5200 deg^2 in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg^2, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent photometric recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic Understanding and Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars at both high and low Galactic latitudes. All the more than half a million stellar spectra obtained with the SDSS spectrograph have been reprocessed through an improved stellar parameters pipeline, which has better determination of metallicity for high metallicity stars.Comment: Astrophysical Journal Supplements, in press (minor updates from submitted version
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