3,230 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

    Variations in the propagation of UH-nuclei

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    Calculations of the propagation of UH-nuclei were improved by extending the number of individual nuclides considered, and by using more recent evaluations of the rigidity dependence of the escape length, the possible source composition, and altered cross sections. The effects of using different expressions for the dependence of abundances on first ionization potentials (FIP) are outlined. The sensitivity of the calculated elemental abundances to the various changes made in the propagation assumptions are discussed

    Stopping relativistic Xe, Ho, Au and U nuclei in nuclear emulsions

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    Nuclei of Xe-54, Ho-67, Au-79 and U-92 accelerated at the Bevalac to energies between 1200 and 900 MeV/n were stopped in nuclear emulsions. The observed residual ranges were compared with those calculated from various models of energy loss and shown to be most consistent with a calculation that includes those higher order correction terms proposed previously to describe the energy loss of highly charged particles, for which the first Born approximation is not valid

    The charge and energy spectra of heavy cosmic ray nuclei

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    A charged particle detector array flown in a high altitude balloon detected and measured some 30,000 cosmic ray nuclei with Z greater than or equal to 12. The charge spectrum at the top of the atmosphere for nuclei with E greater than 650 MeV/n and the energy spectrum for 650 less than or equal to E less than 1800 MeV/n are reported and compared with previously published results. The charge spectrum at the source of cosmic rays is deduced from these data and compared with a recent compilation of galactic abundances

    Gamma ray emission from the region of the galactic center

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    A combination nuclear emulsion-spark chamber gamma ray (E=100 MeV) telescope was used to study the region of sky that includes the Galactic Center. 95% confidence upper limits on the flux from the reported sources G gamma 2 - 3 and Sgr gamma-1 were placed at 4.4 and 8.8 x 10 to the minus 5th power protons/sq cm-sec, and a similar limit on the emission from the Galactic Center as a point source (plus or minus .75 degrees) was placed at 3.3 x 10 to the minus 5th power protons/sq cm-sec. No enhanced emission was observed from the Galactic Plane (plus or minus 6 degrees) and an upper limit of 2 x 10 to the minus 4th power protons/sq cm-sec rad/ was obtained

    Effect of Snowtrapping and Fertilization on Production of Crested Wheatgrass and Native Pastures in Southwest Saskatchewan

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    The benefits of increasing soil water with snow management and fertilizer for annual and perennial crops have been demonstrated for semiarid environments. We examined the combined effect of snow management and fertilizer on forage production. In 1985, vertical wood slat or slotted plastic snow fencing (0.7m high) were erected on crested wheatgrass (Agropyron cristatum) pasture. In 1986, five rates of fertilizer: 400, 200, 100, 50, 0 kg ha-1 nitrogen each with 50 kg ha-1 phosphorous and a sixth treatment with no fertilizer were applied to each side and type of the snowfence. A second site was selected on native range in fall 1986 with fertilizer applied in spring 1987. Samples were harvested from subplots every 1.5m perpindicular to the fence in the subsequent springs until 1991. Production of crested wheatgrass and native range was influenced by the fertility level, type of snowfence, distance and direction from the snowfence

    An experimental dynamic RAM video cache

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    As technological advances continue to be made, the demand for more efficient distributed multimedia systems is also affirmed. Current support for end-to-end QoS is still limited; consequently mechanisms are required to provide flexibility in resource loading. One such mechanism, caching, may be introduced both in the end-system and network to facilitate intelligent load balancing and resource management. We introduce new work at Lancaster University investigating the use of transparent network caches for MPEG-2. A novel architecture is proposed, based on router-oriented caching and the employment of large scale dynamic RAM as the sole caching medium. The architecture also proposes the use of the ISO/IEC standardised DSM-CC protocol as a basic control infrastructure and the caching of pre-built transport packets (UDP/IP) in the data plane. Finally, the work discussed is in its infancy and consequently focuses upon the design and implementation of the caching architecture rather than an investigation into performance gains, which we intend to make in a continuation of the work

    Delivering efficient liver-directed AAV-mediated gene therapy.

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    Adeno-associated virus vectors (AAV) have become the leading technology for liver-directed gene therapy. After the pioneering trials using AAV2 and AAV8 to treat haemophilia B, D’Avola et al. recently reported the first-in-human clinical trial of adeno-associated virus vector serotype 5 (AAV5) in acute intermittent porphyria (AIP). Treatment was reported as safe, but the main surrogate biomarkers of AIP, porphobilinogen (PBG) and delta-aminolevulinate (ALA) were unchanged. This lack of efficacy contrasts with results from the haemophilia B trial using AAV8 capsid by Nathwani et al., which showed a significant and long-lasting improvement of the clinical phenotype. Haemophilia B is an amenable target for successful gene therapy as raising expression of plasma factor IX (FIX) level above 1% can modify the phenotype from severe to moderate. Development of a variety of capsids for clinical application is useful to overcome pre-existing neutralising antibodies. The differences in cell-specific transduction by different AAV serotypes are primarily owing to specificities in cellular uptake or post cell-entry processing. Indeed AAV5 presents several theoretical advantages as an alternative capsid to AAV8 for liver-directed gene therapy: suitable liver tropism, less off-target biodistribution, low seroprevalence in humans and minimal cross-reactivity with other serotypes
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