2,502 research outputs found

    Towards insect inspired visual sensors for robots

    Get PDF
    Flying insects display a repertoire of complex behaviours that are facilitated by their non-standard visual system that if understood would offer solutions for weight- and power- constrained robotic platforms such as micro unmanned aerial vehicles (MUAVs). Crucial to this goal is revealing the specific features of insect eyes that engineered solutions would benefit from possessing, however progress in exploration of the design space has been limited by challenges in accurately replicating insect vision. Here we propose that emerging ray-tracing technologies are ideally placed to realise the high-fidelity replication of the insect visual perspective in a rapid, modular and adaptive framework allowing development of technical specifications for a new class of bio-inspired sensor. A proof-of-principle insect eye renderer is shown and insights into research directions it affords discussed

    Castells, 'Murdochization', Economic Counterpower and Livestreaming

    Get PDF
    In his Information Age trilogy, Manuel Castells documents the transformation of economic power by means of network affordances. In more recent work, he has built an account of the linking of economic power with cultural and political power through ‘Murdochization’ or ‘the networking of networks’. Whilst Castells’ account of power has thus developed to acknowledge the integration of economic, cultural and political interests within networks, his account of ‘counterpower’ remains largely focused on cultural and political resistance in the form of protest. Here we explore a case of economic counterpower, the unauthorized livestreaming of digital sports broadcasts. Analysis of this particular case (of counterpower) is particularly significant, given the centrality of Murdochization in Castells’ account of power in the network society. Emerging out of, alongside, and in response to the growth of, Murdochized digital media sports networks, we explore the scope and limits of livestreaming as a form of economic counterpower and counter-Murdochization. In this article, we document Castells’ theory of network power, the centrality of Murdochization to that account, and the centrality of monopoly control over digital sports broadcasting to Murdochized media empires. The scope and resilience of alternative streaming media in switching live sports programming from pay to view to free sharing is then examined. The failure to date of all attempts to prohibit free streams shows the ongoing viability of such economic counterpower. However, whilst dominant actors cannot eliminate economic counterpower, where dominant actors choose not to broadcast, no switching of content can take place

    Castells, ‘Murdochisation’, Economic Counterpower and Live-Streaming

    Get PDF
    In his Information Age trilogy, Manuel Castells documents the transformation of economic power by means of network affordances. In more recent work, he has built an account of the linking of economic power with cultural and political power through 'Murdochisation', or 'the networking of networks'. Whilst Castells’ account of power has thus developed to acknowledge the integration of economic, cultural and political interests and networks, his account of 'counterpower' remains largely focussed on cultural and political resistance in the form of protest. Here we explore a case of economic counterpower; the unauthorised live-streaming of digital sports broadcasts. Analysis of this particular case (of counterpower) is particularly significant given the centrality of ‘Murdochisation’ in Castells’ account of power in the network society. Emerging out of, alongside, and in response to the growth of Murdochised digital media sports networks, we explore the scope and limits of live-streaming as a form of economic counterpower and counter-Murdochisation. In this article, we document Castells’ theory of network power, the centrality of ‘Murdochisation’ to that account, and the centrality of monopoly control over digital sports broadcasting to Murdochised media empires. The scope and resilience of alternative streaming media in switching live sports programming from pay to view to free sharing is then examined. The failure to date of all attempts to prohibit free streams shows the on-going viability of such economic counterpower. However, whilst dominant actors cannot eliminate economic counterpower, where dominant actors choose not to broadcast, no switching of content can take place

    The Effects of Combination Treatment Using Phenoxodiol and Docetaxel, and Phenoxodiol and Secreted Frizzled-related Protein 4 on Prostate Cancer Cell Lines

    Get PDF
    Although much progress has been made for the treatment of prostate cancer, patients with advanced prostate cancer still have a poor 5 year survival rate. Current practices for hormone-refractory/castrate resistant, metastatic prostate cancer involve the use of taxanes. Docetaxel, in particular, is being incorporated in numerous current clinical trials either as a single or combination agent against androgen-independent prostate cancer. Combination therapies have the potential to increase the effectiveness of drug treatments while simultaneously increasing quality of life by reducing side effects, lowering effective dosage rates, or by increasing effectiveness of one compound once combined with another. Using three diverse human prostate cancer cell lines, LNCap, DU145, and PC3, we studied the effect of the novel prostate cancer drug phenoxodiol in combination with docetaxel by utilizing isobolograms, and found that docetaxelinduced cell death was attenuated by co-treatment or pre-treatment of cells with phenoxodiol. This attenuation is associated with the prevention of cells from entering the G2/M phase of the cell cycle where docetaxel is functional in damaging the spindle fibers, and potentially due to p21WAF1 mediated cell survival after docetaxel treatment.We also investigated the use of the Wnt signaling pathway antagonist secreted frizzled-related protein 4 (sFRP4) to increase the effectiveness of phenoxodiol treatment. We found that, through stabilization of the GSK3β molecule, sFRP4 induces degradation of active β-catenin, which causes an increased sensitivity to isoflavone cytotoxic induction by increasing p21WAF1 expression and decreasing expression of c-Myc, Cyclin-D1, and other potent oncogenes. Phenoxodiol induces significant cytotoxicity when combined with a Wnt/β-catenin receptor blocker such as sFRP4. This promotes the concept that combination therapy of a Wnt inhibitor with phenoxodiol might increase the effectiveness of phenoxodiol and give a subset population of prostate cancer sufferers a more effective treatment regime

    Genetic Factors in Metastatic Progression of Cutaneous Melanoma: the Future Role of Circulating Melanoma Cells in Prognosis and Management

    Get PDF
    The greatest potential for improvement of outcome for patients with Cutaneous Malignant Melanoma lies in the prevention of systemic metastasis. Despite extensive investigation, current prognostic indicators either alone or in combination, although related to melanoma progression, are not sufficient to accurately predict the pattern of progression and outcome for any individual patient. Metastasis related death has been recorded in patients initially diagnosed with early stage tumour as well as in patients many years after initial tumour removal. The trouble finding a predictable pattern in the puzzle of melanoma progression may be linked to the fact that most of the material studied for prognosis is either, cutaneous primaries or metastatic deposits, rather than the melanoma cells in the circulatory system which are responsible for disease progression. In this review article we discuss the potential use of circulating tumour cell (CTC) detection and quantification for identifying patients at risk of metastatic deposits. We also discuss current therapies for the treatment of metastatic melanoma and analyse how CTCs may be used to evaluate the effectiveness of current therapies and to pinpoint patients who require further treatment

    SO(n + 1) Symmetric Solutions of the Einstein Equations in Higher Dimensions

    Full text link
    A method of solving the Einstein equations with a scalar field is presented. It is applied to find higher dimensional vacuum metrics invariant under the group SO(n + 1) acting on n-dimensional spheres.Comment: 11 page

    Lithostratigraphy and biostratigraphy of the Lower Carboniferous (Mississippian) carbonates of the southern Askrigg Block, North Yorkshire, UK

    Get PDF
    A rationalized lithostratigraphy for the Great Scar Limestone Group of the southeast Askrigg Block is established. The basal Chapel House Limestone Formation, assessed from boreholes, comprises shallow-marine to supratidal carbonates that thin rapidly northwards across the Craven Fault System, onlapping a palaeotopographical high of Lower Palaeozoic strata. The formation is of late Arundian age in the Silverdale Borehole, its northernmost development. The overlying Kilnsey Formation represents a southward-thickening and upward-shoaling carbonate development on a south-facing carbonate ramp. Foraminiferal/algal assemblages suggest a late Holkerian and early Asbian age, respectively, for the uppermost parts of the lower Scaleber Force Limestone and upper Scaleber Quarry Limestone members, significantly younger than previously interpreted. The succeeding Malham Formation comprises the lower Cove Limestone and upper Gordale Limestone members. Foraminiferal/ algal assemblages indicate a late Asbian age for the formation, contrasting with the Holkerian age previously attributed to the Cove Limestone. The members reflect a change from a partially shallow-water lagoon (Cove Limestone) to more open-marine shelf (Gordale Limestone), coincident with the onset of marked sea-level fluctuations and formation of palaeokarstic surfaces with palaeosoils in the latter. Facies variations along the southern flank of the Askrigg Block, including an absence of fenestral lime-mudstone in the upper part of the Cove Limestone and presence of dark grey cherty grainstone/packstone in the upper part the Gordale Limestone are related to enhanced subsidence during late Asbian movement on the Craven Fault System. This accounts for the marked thickening of both members towards the Greenhow Inlier

    Tectonic synthesis and contextual setting for the Central North Sea and adjacent onshore areas, 21CXRM Palaeozoic Project

    Get PDF
    This report is designed simply to provide a summary tectonic outline and contextual setting against which offshore seismic and well data relating to the Devono-Carboniferous evolution of the Central North Sea, Forth Approaches, and adjacent UK onshore region can be considered. This summary is intended to help better frame the questions that will arise during interrogation of that data; the findings that result from that analysis are presented elsewhere in the report series (Arsenikos et al., 2015; Kimbell & Williamson, 2015; Monaghan et al., 2015). Apparently contradictory, wrench- or extension-dominated patterns of Lower Carboniferous basin development are recorded in the Forth Approaches, Quadrant 29, North Dogger and Silverpit basins of the Central North Sea, as well as the Midland Valley of Scotland (MVS) and Northumberland and Solway basins onshore. Partitioning Carboniferous deformation across inherited pre-existing Caledonian or Tornquist structures is likely to be an important control on the tectonic architecture developed in these regions during intervals of the geological record in the Carboniferous. Onshore, spatially separate but contemporaneous domains of extension-dominated tectonics versus wrench-dominated tectonics explain the contrasting tectonic framework of the MVS/Forth Approaches region (wrench-dominated) compared with Northumberland Basin (classic ‘stags head’ structure). NE-SW trending Caledonian inheritance strongly controls the domain boundaries and the patterns of deformation created in each of these domains. Offshore, in the Devono-Carboniferous basins of the Central North Sea, the likelihood that strain is partitioned in a similar way across features inherited from the NW-SE Tornquist trend is proposed and examined. The data currently under consideration suggests that a NW-SE trending wrench-dominated domain is spatially associated with the region underlain by the Dogger Granite pluton; domains affected by extension-dominated tectonics appear to be arranged on either side of that feature, namely the Quadrant 29 and North Dogger basins to the NE, and the Silverpit Basin to the SW. Extension is expressed as a NE-SW directed stretch in both of these domains. Patterns of broadly N-S trending fold axes need to be carefully assessed in terms of their structural setting, as folding cannot implicitly be linked with inversion/compression when partitioned strains are developed. Superficially similar features can develop in the MVS in dextral transpression, in north Northumberland buttressed around the Cheviot Granite in overall dextral wrench, and as superimposed late compressional folds in end-Variscan convergence, for example in the Boldon syncline of County Durham. Offshore, similar inversion effects can be seen in the patterns of transpressive faulting associated with features such as the Murdoch Ridge, and with examples of superimposed NE-SW trending extensional faults active in the latest Carboniferous to early Permian
    • …
    corecore