591 research outputs found

    Human response to vibration in residential environments (NANR209), technical report 2: measurement of response

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    Based on a review of the literature and the best practice guidance available, a social survey questionnaire was developed to measure residents’ self-reported annoyance and to provide data suitable for establishing exposure-response relationships between levels of annoyance and levels of vibration. The development of the questionnaire was influenced by a number of previous studies such as: the social survey questionnaire developed for the NANR172 Pilot Study of this research (Defra, 2007); best practice guidelines for the development of socio-acoustic surveys issued by ICBEN and presented in the current International Standard (Fields et al., 2001; ISO/TS 15666:2003); the Nordtest Method (2001) for the development of socio-vibration surveys, and a peer review of the social survey questionnaire by international experts in the field. In order to avoid influencing responses and reasons for participation in the research, the survey was introduced as a survey of neighbourhood satisfaction. The questionnaire design, through the use of sections, enables new sections to be added to the questionnaire so that specific vibration sources can be investigated in more depth. In addressing the ‘response’ component in the ‘exposure-response’ relationship, the questionnaire was designed to yield interval-level measurement data suitable for analysis with vibration measurement data via two response scales: the five-point semantic and the eleven-point numerical scales. This decision was largely founded upon the ability of the two scales to meet the criteria established by ICBEN (Fields et al., 2001) for socio-acoustic survey design. Detailed procedures were documented, following the field trial of the questionnaire, in terms of the role of the interviewer, the recording of information and the transfer of the data to the relevant database for subsequent analysis and to inform the vibration team responsible for the ‘exposure’ component of this research project

    Convectively driven coastal currents in a rotating basin

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    Density driven coastal currents were produced in the laboratory by differentially heating and cooling the end walls of a rotating rectangular cavity. After turning on the heat flux, intrusions propagated along the side walls of the cavity under an inertial buoyancy balance, with a geostrophic cross-stream balance. These boundary currents were internally stratified in temperature, while the environment during the early stages of development of the flow was isothermal. Rotational instabilities developed on the edge of the currents and broke to form cyclone-anticyclone eddy pairs. Measurements were made of the intrusion velocity, the temporal development of the width of the boundary currents, their internal thermal structure, and the characteristics of the unstable waves, including their growth rates, wavelengths, and phase speeds. Comparisons are made with previous field observations of the Leeuwin Current off Western and Southern Australia

    EarthN: A new Earth System Nitrogen Model

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    The amount of nitrogen in the atmosphere, oceans, crust, and mantle have important ramifications for Earth's biologic and geologic history. Despite this importance, the history and cycling of nitrogen in the Earth system is poorly constrained over time. For example, various models and proxies contrastingly support atmospheric mass stasis, net outgassing, or net ingassing over time. In addition, the amount available to and processing of nitrogen by organisms is intricately linked with and provides feedbacks on oxygen and nutrient cycles. To investigate the Earth system nitrogen cycle over geologic history, we have constructed a new nitrogen cycle model: EarthN. This model is driven by mantle cooling, links biologic nitrogen cycling to phosphate and oxygen, and incorporates geologic and biologic fluxes. Model output is consistent with large (2-4x) changes in atmospheric mass over time, typically indicating atmospheric drawdown and nitrogen sequestration into the mantle and continental crust. Critical controls on nitrogen distribution include mantle cooling history, weathering, and the total Bulk Silicate Earth+atmosphere nitrogen budget. Linking the nitrogen cycle to phosphorous and oxygen levels, instead of carbon as has been previously done, provides new and more dynamic insight into the history of nitrogen on the planet.Comment: 36 pages, 12 figure

    On the enigmatic mid-Proterozoic : Single-lid versus plate tectonics

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    The mid-Proterozoic (ca. 1850-850 Ma) is a peculiar period of Earth history in many respects: ophiolites and passive margins of this age are rare, whereas anorthosite and A-type granite suites are abundant; metamorphic rocks typically record high thermobaric (temperature/pressure) ratios, whereas ultrahigh pressure (UHP) rocks are rare; and the abundance of economic mineral deposits features rare porphyry Cu-Au and abundant Ni-Cu and Fe-oxide Cu-Ag (IOCG) deposit types. These collective observations have been used to propose that a stagnant-lid, or single-lid, tectonic regime operated at this time, between periods of plate tectonics in the Paleoproterozoic and Neoproterozoic. In our reappraisal of the mid -Proterozoic geological record, we not only assess the viability of the single-lid hypothesis for each line of evidence, but also that of the plate tectonic alternative. We find that evidence for the single-lid hypothesis is equivocal in all cases, whereas for plate tectonics the evidence is equivocal or supporting. We therefore find no reason to abandon a plate tectonic model for the mid-Proterozoic time period. Instead, we propose that the peculiarities of this enigmatic interval can be reconciled through the combination of two processes working in tandem: secular mantle cooling and the exceptionally long tenure and incomplete breakup of Earth's first supercontinent, where both of these phenomena had a dramatic effect on lithospheric behaviour and its resulting imprint in the geological record. (c) 2022 British Geological Survey (c) UKRI 2022. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

    Oldham and Rochdale new build research : Resident research

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    In 2007 Oldham and Rochdale Partners in Action commissioned a survey of New Build accommodation in order to ‘evaluate the effectiveness of new build in attracting and retaining economically active people in the pathfinder areas of Oldham and Rochdale and to create mixed communities in terms of income, ethnicity and tenure type’. This document is a compilation of specific scheme reports detailing the consultation process and resulting findings. In order to explore the schemes in depth and highlight the idiosyncrasies each scheme is discussed in turn. In addition to this report there are three further reports: one provides the findings from the design assessment of the schemes; one details issues associated with the consultation and engagement of residents across all schemes; and, the remaining report provides an overview of issues arising over all schemes, linked into the findings from the design assessment, and suggests some recommendations

    Database Learning: Toward a Database that Becomes Smarter Every Time

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    In today's databases, previous query answers rarely benefit answering future queries. For the first time, to the best of our knowledge, we change this paradigm in an approximate query processing (AQP) context. We make the following observation: the answer to each query reveals some degree of knowledge about the answer to another query because their answers stem from the same underlying distribution that has produced the entire dataset. Exploiting and refining this knowledge should allow us to answer queries more analytically, rather than by reading enormous amounts of raw data. Also, processing more queries should continuously enhance our knowledge of the underlying distribution, and hence lead to increasingly faster response times for future queries. We call this novel idea---learning from past query answers---Database Learning. We exploit the principle of maximum entropy to produce answers, which are in expectation guaranteed to be more accurate than existing sample-based approximations. Empowered by this idea, we build a query engine on top of Spark SQL, called Verdict. We conduct extensive experiments on real-world query traces from a large customer of a major database vendor. Our results demonstrate that Verdict supports 73.7% of these queries, speeding them up by up to 23.0x for the same accuracy level compared to existing AQP systems.Comment: This manuscript is an extended report of the work published in ACM SIGMOD conference 201

    VerdictDB: Universalizing Approximate Query Processing

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    Despite 25 years of research in academia, approximate query processing (AQP) has had little industrial adoption. One of the major causes of this slow adoption is the reluctance of traditional vendors to make radical changes to their legacy codebases, and the preoccupation of newer vendors (e.g., SQL-on-Hadoop products) with implementing standard features. Additionally, the few AQP engines that are available are each tied to a specific platform and require users to completely abandon their existing databases---an unrealistic expectation given the infancy of the AQP technology. Therefore, we argue that a universal solution is needed: a database-agnostic approximation engine that will widen the reach of this emerging technology across various platforms. Our proposal, called VerdictDB, uses a middleware architecture that requires no changes to the backend database, and thus, can work with all off-the-shelf engines. Operating at the driver-level, VerdictDB intercepts analytical queries issued to the database and rewrites them into another query that, if executed by any standard relational engine, will yield sufficient information for computing an approximate answer. VerdictDB uses the returned result set to compute an approximate answer and error estimates, which are then passed on to the user or application. However, lack of access to the query execution layer introduces significant challenges in terms of generality, correctness, and efficiency. This paper shows how VerdictDB overcomes these challenges and delivers up to 171×\times speedup (18.45×\times on average) for a variety of existing engines, such as Impala, Spark SQL, and Amazon Redshift, while incurring less than 2.6% relative error. VerdictDB is open-sourced under Apache License.Comment: Extended technical report of the paper that appeared in Proceedings of the 2018 International Conference on Management of Data, pp. 1461-1476. ACM, 201

    Homozygosity for a missense mutation in the 67 kDa isoform of glutamate decarboxylase in a family with autosomal recessive spastic cerebral palsy: parallels with Stiff-Person Syndrome and other movement disorders

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    Background Cerebral palsy (CP) is an heterogeneous group of neurological disorders of movement and/or posture, with an estimated incidence of 1 in 1000 live births. Non-progressive forms of symmetrical, spastic CP have been identified, which show a Mendelian autosomal recessive pattern of inheritance. We recently described the mapping of a recessive spastic CP locus to a 5 cM chromosomal region located at 2q24-31.1, in rare consanguineous families. Methods Here we present data that refine this locus to a 0.5 cM region, flanked by the microsatellite markers D2S2345 and D2S326. The minimal region contains the candidate gene GAD1, which encodes a glutamate decarboxylase isoform (GAD67), involved in conversion of the amino acid and excitatory neurotransmitter glutamate to the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Results A novel amino acid mis-sense mutation in GAD67 was detected, which segregated with CP in affected individuals. Conclusions This result is interesting because auto-antibodies to GAD67 and the more widely studied GAD65 homologue encoded by the GAD2 gene, are described in patients with Stiff-Person Syndrome (SPS), epilepsy, cerebellar ataxia and Batten disease. Further investigation seems merited of the possibility that variation in the GAD1 sequence, potentially affecting glutamate/GABA ratios, may underlie this form of spastic CP, given the presence of anti-GAD antibodies in SPS and the recognised excitotoxicity of glutamate in various contexts

    Developing core sets for persons following amputation based on the International Classification of Functioning, Disability and Health as a way to specify functioning

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    Amputation is a common late stage sequel of peripheral vascular disease and diabetes or a sequel of accidental trauma, civil unrest and landmines. The functional impairments affect many facets of life including but not limited to: Mobility; activities of daily living; body image and sexuality. Classification, measurement and comparison of the consequences of amputations has been impeded by the limited availability of internationally, multiculturally standardized instruments in the amputee setting. The introduction of the International Classification of Functioning, Disability and Health (ICF) by the World Health Assembly in May 2001 provides a globally accepted framework and classification system to describe, assess and compare function and disability. In order to facilitate the use of the ICF in everyday clinical practice and research, ICF core sets have been developed that focus on specific aspects of function typically associated with a particular disability. The objective of this paper is to outline the development process for the ICF core sets for persons following amputation. The ICF core sets are designed to translate the benefits of the ICF into clinical routine. The ICF core sets will be defined at a Consensus conference which will integrate evidence from preparatory studies, namely: (a) a systematic literature review regarding the outcome measures of clinical trails and observational studies, (b) semi-structured patient interviews, (c) international experts participating in an internet-based survey, and (d) cross-sectional, multi-center studies for clinical applicability. To validate the ICF core sets field-testing will follow. Invitation for participation: The development of ICF Core Sets is an inclusive and open process. Anyone who wishes to actively participate in this process is invited to do so
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