41 research outputs found

    kD-STR : a method for spatio-temporal data reduction and modelling

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    Analysing and learning from spatio-temporal datasets is an important process in many domains, including transportation, healthcare and meteorology. In particular, data collected by sensors in the environment allows us to understand and model the processes acting within the environment. Recently, the volume of spatio-temporal data collected has increased significantly, presenting several challenges for data scientists. Methods are therefore needed to reduce the quantity of data that needs to be processed in order to analyse and learn from spatio-temporal datasets. In this article, we present the -Dimensional Spatio-Temporal Reduction method (D-STR) for reducing the quantity of data used to store a dataset whilst enabling multiple types of analysis on the reduced dataset. D-STR uses hierarchical partitioning to find spatio-temporal regions of similar instances, and models the instances within each region to summarise the dataset. We demonstrate the generality of D-STR with three datasets exhibiting different spatio-temporal characteristics and present results for a range of data modelling techniques. Finally, we compare D-STR with other techniques for reducing the volume of spatio-temporal data. Our results demonstrate that D-STR is effective in reducing spatio-temporal data and generalises to datasets that exhibit different properties

    A new subsurface record of the Pliensbachianā€“Toarcian, Lower Jurassic, of Yorkshire

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    Here, we describe the upper Pliensbachian to middle Toarcian stratigraphy of the Doveā€™s Nest borehole, which was drilled near Whitby, North Yorkshire, in 2013. The core represents a single, continuous vertical section through unweathered, immature Lower Jurassic sedimentary rocks. The thickness of the Lias Group formations in the Doveā€™s Nest core is approximately the same as that exposed along the North Yorkshire coast between Hawsker Bottoms and Whitby. The studied succession consists of epeiric-neritic sediments and comprises cross-laminated very fine sandstones, (oolitic) ironstones, and argillaceous mudstones. Dark argillaceous mudstone is the dominant lithology. These sediments were deposited in the Cleveland Basin, a more subsident area of an epeiric sea, the Laurasian Sea. We present a set of geochemical data that includes organic carbon isotope ratios (Ī“13Corg) and total organic carbon (TOC). The Ī“13Corg record contains a negative excursion across the Pliensbachianā€“Toarcian boundary and another in the lower Toarcian that corresponds to the Toarcian Oceanic Anoxic Event (T-OAE). Below the T-OAE negative excursion, Ī“13Corg values are less13C-depleted than above it. We find no evidence of a long-term Ī“13 Corg positive excursion. TOC values below the T-OAE negative excursion are lower than above it. Sedimentary evidence suggests that, during much of the Pliensbachianā€“Toarcian interval, the seafloor of the Cleveland Basin was above storm wave-base and that storm-driven bottom currents were responsible for much sediment erosion, transport, and redeposition during the interval of oceanic anoxia. The abrupt shifts observed in the Ī“13Corg record (lower Toarcian) are likely to reflect the impact of erosion by storms on the morphology of the Ī“13C record of the T-OAE

    Reducing and linking spatio-temporal datasets with kD-STR

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    When linking spatio-temporal datasets, the kD-STR algorithm can be used to reduce the datasets and speed up the linking process. However, kD-STR can sacrifice accuracy in the linked dataset whilst retaining unnecessary information. To overcome this, we propose a preprocessing step that removes unnecessary information and an alternative heuristic for kD-STR that prioritises accuracy in the linked output. These are evaluated in a case study linking a road condition dataset with air temperature, rainfall and road traffic data. In this case study, we found the alternative heuristic achieved a 19% improvement in mean error for the linked air temperature features and an 18% reduction in storage used for the rainfall dataset compared to the original kD-STR heuristic. The results in this paper support our hypothesis that, at worse, our alternative heuristic will yield a similar error and storage overhead for linking scenarios as the original kD-STR heuristic. However, in some cases it can give a reduction that is more accurate when linking the datasets whilst using less storage than the original kD-STR algorithm

    Inducible chromatin priming is associated with the establishment of immunological memory in T cells

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    Immunological memory is a defining feature of vertebrate physiology, allowing rapid responses to repeat infections. However, the molecular mechanisms required for its establishment and maintenance remain poorly understood. Here, we demonstrated that the first steps in the acquisition of T-cell memory occurred during the initial activation phase of naĆÆve T cells by an antigenic stimulus. This event initiated extensive chromatin remodeling that reprogrammed immune response genes toward a stably maintained primed state, prior to terminal differentiation. Activation induced the transcription factors NFAT and AP-1 which created thousands of new DNase I-hypersensitive sites (DHSs), enabling ETS-1 and RUNX1 recruitment to previously inaccessible sites. Significantly, these DHSs remained stable long after activation ceased, were preserved following replication, and were maintained in memory-phenotype cells. We show that primed DHSs maintain regions of active chromatin in the vicinity of inducible genes and enhancers that regulate immune responses. We suggest that this priming mechanism may contribute to immunological memory in T cells by facilitating the induction of nearby inducible regulatory elements in previously activated T cells

    "The Mystery of the Raddlesham Mumps": A case study for combined storytelling in a theatre play and Virtual Reality

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    ā€œThe Mystery of the Raddlesham Mumpsā€ is a poem by Murray Lachlan Young, aimed at both children and adults. This poem has been adapted as a theatre play with a short prequel as a Virtual Reality (VR)/tablet app. We used this unique combination to explore the potential interaction between these different media elements for the level of ā€œpresenceā€ and ā€œimmersionā€ in the story (i.e. the level to which one can imagine oneself within the story at the expense of the sense of physical time and space). The theatre audience had the opportunity to play the VR/tablet app in the foyer before the performance started. After the performance, a questionnaire measured participantsā€™ level of immersion and presence in the theatre play and their enjoyment of both play and app. The results showed that people of all ages interacted with and liked the app. Ratings for the play were also high and did not depend on prior engagement with the app. However, the play was liked more by adults than children, and the reverse was true for the app, suggesting a potential generation shift in multimedia story telling

    Time-sculptures of Terrifying Ambiguity: Staging Inner Space and Migrating Realities in Analogue's Living Film Set

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    This article examines Analogueā€™s Living Film Set, an interactive theatre piece which uses miniature film sets, multi-touch surface technology and live video feeds to reframe my semi-remembered memories from the mid-1980s as a collective participatory experience. Drawing on new wave novelist J. G. Ballardā€™s notion of childhood memory as ā€˜time-sculptures of terrifying ambiguityā€™ [Ballard, J. G. 1963. ā€œTime, Memory and Inner Space.ā€ J. G. Ballard website (originally published in The Woman Journalist Magazine). Accessed August 6, 2015. http://www.jgballard.ca/non_fiction/jgb_time_memory_innerspace.html], I will demonstrate how my childhood town of Shepperton has been overwritten in both Ballardian literary fiction and the incursion of cinematic artifice from the neighbouring activities of Shepperton Film Studios. I argue that the ambiguity of my recollections and the contamination of my lived history with ā€˜prosthetic memoriesā€™ [Landsberg, Alison. 2004. Prosthetic Memory: The Transformation of American Remembrance in the Age of Mass Culture. New York, NY: Columbia UP, 20ā€“21.] has provided a creative space to re-enact the blended hyperreality of my early childhood through the workā€™s intermedial form. I will conclude by examining how the shifting reality status of the media used within the performance intersects with the notion of ā€˜time-sculpturesā€™ and problematises what Carol Martin [(2013). Theatre of the Real. Basingstoke: Palgrave Macmillan.] has identified as ā€˜theatre of the realā€™

    Cosmological parameters from SDSS and WMAP

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    We measure cosmological parameters using the three-dimensional power spectrum P(k) from over 200,000 galaxies in the Sloan Digital Sky Survey (SDSS) in combination with WMAP and other data. Our results are consistent with a ``vanilla'' flat adiabatic Lambda-CDM model without tilt (n=1), running tilt, tensor modes or massive neutrinos. Adding SDSS information more than halves the WMAP-only error bars on some parameters, tightening 1 sigma constraints on the Hubble parameter from h~0.74+0.18-0.07 to h~0.70+0.04-0.03, on the matter density from Omega_m~0.25+/-0.10 to Omega_m~0.30+/-0.04 (1 sigma) and on neutrino masses from <11 eV to <0.6 eV (95%). SDSS helps even more when dropping prior assumptions about curvature, neutrinos, tensor modes and the equation of state. Our results are in substantial agreement with the joint analysis of WMAP and the 2dF Galaxy Redshift Survey, which is an impressive consistency check with independent redshift survey data and analysis techniques. In this paper, we place particular emphasis on clarifying the physical origin of the constraints, i.e., what we do and do not know when using different data sets and prior assumptions. For instance, dropping the assumption that space is perfectly flat, the WMAP-only constraint on the measured age of the Universe tightens from t0~16.3+2.3-1.8 Gyr to t0~14.1+1.0-0.9 Gyr by adding SDSS and SN Ia data. Including tensors, running tilt, neutrino mass and equation of state in the list of free parameters, many constraints are still quite weak, but future cosmological measurements from SDSS and other sources should allow these to be substantially tightened.Comment: Minor revisions to match accepted PRD version. SDSS data and ppt figures available at http://www.hep.upenn.edu/~max/sdsspars.htm

    Harms from discharge to primary care:mixed methods analysis of incident reports

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    Background Discharge from hospital presents significant risks to patient safety, with up to one in five patients experiencing adverse events within 3 weeks of leaving hospital. Aim To describe the frequency and types of patient safety incidents associated with discharge from secondary to primary care, and commonly described contributory factors to identify recommendations for practice. Design and setting A mixed methods analysis of 598 patient safety incident reports in England and Wales related to ā€˜Dischargeā€™ from the National Reporting and Learning System. Method Detailed data coding (with 20% double-coding), data summaries generated using descriptive statistical analysis, and thematic analysis of special-case sample of reports. Incident type, contributory factors, type, and level of harm were described, informing recommendations for future practice. Results A total of 598 eligible reports were analysed. The four main themes were: errors in discharge communication (n = 151; 54% causing harm); errors in referrals to community care (n = 136; 73% causing harm); errors in medication (n = 97; 87% causing harm); and lack of provision of care adjuncts such as dressings (n = 62; 94% causing harm). Common contributory factors were staff factors (not following referral protocols); and organisational factors (lack of clear guidelines or inefficient processes). Improvement opportunities include developing and testing electronic discharge methods with agreed minimum information requirements and unified referrals systems to community care providers; and promoting a safety culture with ā€˜safe dischargeā€™ checklists, discharge coordinators, and family involvement. Conclusion Significant harm was evident due to deficits in the discharge process. Interventions in this area need to be evaluated and learning shared widely
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