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Design, characterization, and fabrication of solar-retroreflective cool-wall materials
Raising urban albedo increases the fraction of incident sunlight returned to outer space, cooling cities and their buildings. We evaluated the angular distribution of solar radiation incident on exterior walls in 17 U S. climates to develop performance parameters for solar-retroreflective walls, then applied first-principle physics and ray-tracing simulations to explore designs. Our analysis indicates that retroreflective walls must function at large incidence angles to reflect a substantial portion of summer sunlight, and that this will be difficult to attain with materials that rely on total internal reflection. Gonio-spectrophotometer measurements of the solar spectral bi-directional reflectivity of a bicycle reflector showed little to no retroreflection at large incidence angles. Visual comparisons of retroreflection to specular first-surface reflection for four different retroreflective safety films using violet and green lasers suggest their retroreflection to be no greater than 0.09 at incidence angles up to 45°, and no greater than 0.30 at incidence angles of up to 70°. Attempts to produce a two-surface retroreflector with orthogonal mirror grooves by cutting and polishing an aluminum block indicate that residual surface roughness impedes retroreflection. Ongoing efforts focus on forming orthogonal surfaces with aluminized Mylar film, a material with very high specular reflectance across the solar spectrum. We investigated (1) folding or stamping a free film; (2) adhering the film to a pre-shaped substrate; or (3) attaching the film to a flat ductile substrate, then shaping. The latter two methods were more successful but yielded imperfect right angles
Corporate Philanthropy as a Context for Moral Agency, a MacIntyrean Enquiry
It has been claimed that âvirtuous structuresâ can foster moral agency in organisations. We investigate this in the context of employee involvement in corporate philanthropy, an activity whose moral status has been disputed. Employing Alasdair MacIntyreâs account of moral agency, we analyse the results of eight focus groups with employees engaged in corporate philanthropy in an employee-owned retailer, the John Lewis Partnership. Within this organisational context, Employee-Partnersâ moral agency was evidenced in narrative accounts of their engagement in philanthropic activities and in their disputes about the moral status of corporate philanthropy
Human exposure assessment of different arsenic species in household water sources in a high risk arsenic area
Understanding arsenic speciation in water is important for managing the potential health risks associated with chronic arsenic exposure. Most arsenic monitoring studies to date have only measured total arsenic, with few looking at arsenic species. This study assessed 228 ground water sources in six unstudied villages in Pakistan for total, inorganic and organic arsenic species using ion chromatography inductively coupled plasma collision reaction cell mass spectrometry. The concentration levels approached 3090 ÎŒg Lâ1 (95% CI, 130.31, 253.06) for total arsenic with a median of 57.55 ”g L-1, 3430 ÎŒg Lâ1 (median=52) for arsenate (As+5) and 100 ÎŒg Lâ1 (median=0.37) for arsenite (As+3). Exceedance of the WHO provisional guideline value for arsenic in drinking water (10 ÎŒg Lâ1) occurred in 89% of water sources. Arsenic was present mainly as arsenate (As+5). Average daily intake of total arsenic for 398 residents living in the sampled houses was found up to 236.51 ”g kgâ1 dayâ1. This exposure estimate has indicated that 63% of rural residents exceeded the World Health Organizationâs provisional tolerable daily intake (PTDI) of 2.1 ”g kgâ1 dayâ1 body weight. Average daily intake of As+5 was found to be 15.63 ”g kgâ1 dayâ1 (95% CI, 5.53, 25.73) for children †16 and 15.07 ”g kgâ1 dayâ1 (95% CI, 10.33, 18.02) for adults. A mean daily intake of 0.09 ”g kgâ1 dayâ1 was determined for As+3 for children and 0.26 ”g kgâ1 dayâ1 for adults. Organic arsenic species such as monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and Arsenobetaine (AsB) were found to be below their method detection limits (MDLs)
Percutaneous coronary intervention in the elderly: changes in case-mix and periprocedural outcomes in 31758 patients treated between 2000 and 2007
<p>Background: The elderly account for an increasing proportion of the population and have a high prevalence of coronary heart disease. Percutaneous coronary intervention (PCI) is the most common method of revascularization in the elderly. We examined whether the risk of periprocedural complications after PCI was higher among elderly (age â„75 years) patients and whether it has changed over time.</p>
<p>Methods and Results: The Scottish Coronary Revascularization Register was used to undertake a retrospective cohort study on all 31 758 patients undergoing nonemergency PCI in Scotland between April 2000 and March 2007, inclusive. There was an increase in the number and percentage of PCIs undertaken in elderly patients, from 196 (8.7%) in 2000 to 752 (13.9%) in 2007. Compared with younger patients, the elderly were more likely to have multivessel disease, multiple comorbidity, and a history of myocardial infarction or coronary artery bypass grafting (Ï2 tests, all P<0.001). The elderly had a higher risk of major adverse cardiovascular events within 30 days of PCI (4.5% versus 2.7%, Ï2 test P<0.001). Over the 7 years, there was a significant increase in the proportion of elderly patients who had multiple comorbidity (Ï2 test for trend, P<0.001). Despite this, the underlying risk of complications did not change significantly over time either among the elderly (Ï2 test for trend, P=0.142) or overall (Ï2 test for trend, P=0.083).</p>
<p>Conclusions: Elderly patients have a higher risk of periprocedural complications and account for an increasing proportion of PCIs. Despite this, the risk of complications after PCI has not increased over time.</p>
Aircraft remote sensing of soil moisture and hydrologic parameters, Taylor Creek, Florida, and Little River, Georgia, 1979 data report
Experiments were conducted to evaluate aircraft remote sensing techniques for hydrology in a wide range of physiographic and climatic regions using several sensor platforms. The data were collected in late 1978 and during 1979 in two humid areas--Taylor Creek, Fla., and Little River, Ga. Soil moisture measurements and climatic observations are presented as well as the remote sensing data collected using thermal infrared, passive microwave, and active microwave systems
Glass-Like Heat Conduction in High-Mobility Crystalline Semiconductors
The thermal conductivity of polycrystalline semiconductors with type-I
clathrate hydrate crystal structure is reported. Ge clathrates (doped with Sr
and/or Eu) exhibit lattice thermal conductivities typical of amorphous
materials. Remarkably, this behavior occurs in spite of the well-defined
crystalline structure and relatively high electron mobility (). The dynamics of dopant ions and their interaction with the
polyhedral cages of the structure are a likely source of the strong phonon
scattering.Comment: 4 pages, 3 postscript figures, to be published, Phys. Rev. Let
Paedophiles in the community: inter-agency conflict, news leaks and the local press
This article explores the leaking of confidential information about secret Home Office plans to house convicted paedophiles within a local community (albeit inside a prison). It argues that a politics of paedophilia has emerged in which inter-agency consensus on the issue of âwhat to doâ with high-profile sex offenders has broken down. Accordingly, the article situates newspaper âoutingâ of paedophiles in the community in relation to vigilante journalism and leaked information from official agencies. The article then presents research findings from a case study of news events set in train following a whistle-blowing reaction by Prison Officersâ Association officials to Home Office plans. Drawing from a corpus of 10 interviews with journalists and key protagonists in the story, the article discusses both the dynamics of whistle blowing about paedophiles and also what happens after the whistle has blown
Eastern Black Nightshade
The nightshade species of North America consist of black nightshade (Solanum nigrum L.), American black nightshade (Solanum americanum Mill.), hairy nightshade (Solanum surrachoides Sendt.) and eastern black nightshade (Solanum ptycanthum Dun.). Eastern black nightshade is a problem weed in many soybean producing areas and is the predominant problem nightshade in Kentucky. In addition to field crops, the nightshades are also problem weeds in canning peas (Pisum sativum L.), field beans (Phaseolus vulgaris L.), potatoes (Solanum tuberosum L.) and tomatoes (Lycopersicon esculentum Mill.). Previously, most nightshades in Kentucky have been referred to as black nightshade. It is now known that black nightshade occurs in the U.S. only in the western states, while eastern black. nightshade is commonly found in many states east of the Rocky Mountains. These species are similar in their gross morphology and are easily confused with each other. When grown under different environmental conditions, the nightshades may vary considerably in many taxonomic characteristics frequently used for identification and make identification more difficult (Ogg, A.G., B.p. Rogers and E.S. Schilling, 1981)
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