178 research outputs found

    A Comparison of the Behavior of Single Crystalline and Nanowire Array ZnO Photoanodes

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    The photoelectrochemical behavior of n-type ZnO nanowire arrays was compared to the behavior of single crystalline n-ZnO photoelectrodes in contact with either 0.50 M K_(2)SO_4(aq) at pH 6.0 or Fe(CN)_(4)^(3ā€“/4ā€“)(aq). The use of a thin film of ZnO as a seed layer produced dense nanowire arrays in which the ZnO nanowires were preferentially oriented perpendicular to the substrate. The average diameter of the ZnO nanowires that were produced by two different growth conditions was ~125 and ~175 nm, respectively, with a nanowire length of 2ā€“4 Ī¼m. Under simulated 1 Sun Air Mass 1.5 illumination conditions, the ZnO nanowire arrays exhibited open-circuit potentials, E_oc, and short-circuit photocurrent densities, J_sc, that were very close to the values observed from single crystal n-type ZnO photoanodes in contact with these same electrolytes. Device physics simulations were in accord with the experimentally observed behavior, indicating that, under certain combinations of materials properties and interface recombination velocities, the use of nanostructured light absorbers can provide an approach to efficient photoelectrochemical solar energy-conversion systems

    Patterns of production and consumption of coarse to semi-fine pottery at Early Iron Age Knossos

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    This paper presents the results of a large-scale petrological study of Early Iron Age coarsewares from North-Central Crete. 210 samples were taken for analysis from six locations at Knossos, representing distinct funerary, domestic and ritual contexts. The bulk of these (188) can be divided into seven fabric groups, with 22 loners or pairs. Four of the seven fabrics exhibit a mineralogy that is consistent with local geology. Three of the fabric groups however appear to be non-local, and two of these fabrics are cooking wares. A non-Cretan,Cycladic sources is suggested for these two fabric groups. There appears to be a major change in the source of Knossian fabrics after 850 BC, and this may be linked to wider Mediterranean connections

    Association of Accelerometry-Measured Physical Activity and Cardiovascular Events in Mobility-Limited Older Adults: The LIFE (Lifestyle Interventions and Independence for Elders) Study.

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    BACKGROUND:Data are sparse regarding the value of physical activity (PA) surveillance among older adults-particularly among those with mobility limitations. The objective of this study was to examine longitudinal associations between objectively measured daily PA and the incidence of cardiovascular events among older adults in the LIFE (Lifestyle Interventions and Independence for Elders) study. METHODS AND RESULTS:Cardiovascular events were adjudicated based on medical records review, and cardiovascular risk factors were controlled for in the analysis. Home-based activity data were collected by hip-worn accelerometers at baseline and at 6, 12, and 24 months postrandomization to either a physical activity or health education intervention. LIFE study participants (n=1590; age 78.9Ā±5.2 [SD] years; 67.2% women) at baseline had an 11% lower incidence of experiencing a subsequent cardiovascular event per 500 steps taken per day based on activity data (hazard ratio, 0.89; 95% confidence interval, 0.84-0.96; P=0.001). At baseline, every 30 minutes spent performing activities ā‰„500 counts per minute (hazard ratio, 0.75; confidence interval, 0.65-0.89 [P=0.001]) were also associated with a lower incidence of cardiovascular events. Throughout follow-up (6, 12, and 24 months), both the number of steps per day (per 500 steps; hazard ratio, 0.90, confidence interval, 0.85-0.96 [P=0.001]) and duration of activity ā‰„500 counts per minute (per 30 minutes; hazard ratio, 0.76; confidence interval, 0.63-0.90 [P=0.002]) were significantly associated with lower cardiovascular event rates. CONCLUSIONS:Objective measurements of physical activity via accelerometry were associated with cardiovascular events among older adults with limited mobility (summary score >10 on the Short Physical Performance Battery) both using baseline and longitudinal data. CLINICAL TRIAL REGISTRATION:URL: http://www.clinicaltrials.gov. Unique identifier: NCT01072500

    Environment and Rural Affairs Monitoring & Modelling Programme ā€“ ERAMMP Year 1 Report 12TA1: ā€˜Quick Startā€™ Modelling (Phase 1) Technical Annex.

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    Farmscoper is a decision support tool that can be used to assess diffuse agricultural pollutant loads on a farm and quantify the impacts of farm mitigation methods on these pollutants. The farm systems within the tool can be customised to reflect management and environmental conditions representative of farming across England and Wales. The tool contains over 100 mitigation methods, including many of those in the latest Defra Mitigation Method User Guide

    Environment and Rural Affairs Monitoring & Modelling Programme ā€“ ERAMMP Year 1 Report 12: ā€˜Quick Startā€™ Modelling (Phase 1)

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    The potential impact of Brexit on the farming sector and wider environment is just one of the many challenges facing the Welsh Government. There are a range of decision and modelling tools which can be used to explore potential outcomes and the areas at risk where the environmental regulatory floor needs to be enhanced or social transition programmes put in place. The same tools can also be used to explore a range of ā€˜what ifā€™ scenarios for different land management options which could be included in new Payment for Ecosystem Service (PES) schemes or in national land management payment schemes to replace CAP. To meet this challenge in Wales, a partnership between the Welsh Government, their stakeholders and a consortium of research organisations led by the Centre for Ecology and Hydrology (CEH) was formed. This partnership, called ERAMMP, (https://erammp.wales/en) combined expert knowledge and a range of decision and modelling tools to examine potential changes in agricultural land use that might result from Brexit, and to explore potential benefits of new land management options
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