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This paper reviews 23 studies that have examined safety climate within commercial and military aviation. The safety climate factors identified in the aviation safety climate questionnaires were found to be consistent with the literature examining safety climate in non-aviation high reliability organizations. Therefore, it was concluded that the aviation safety climate tools had some construct validity (the extent to which the questionnaire measures what it is intended to measure). However, the majority of the studies made no attempt to establish the discriminate validity (the ability of the tool to differentiate between organizations or personnel with different levels of safety performance) of the tools. It is recommended that rather than constructing more aviation safety climate questionnaires, researchers should focus on establishing the construct and discriminate validity of existing measures by correlating safety climate with other metrics of safety performance. It is recognized that the accident rate in commercial aviation is too low to provide a sufficiently sensitive measure of safety performance. However, there are other measures of safety performance, collected as part of a company’s Aviation Safety Action Program or Flight Operational Quality Assurance, which could be used to assess the discriminate validity of an aviation safety climate tool. 相似文献
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Edward W. Matthews Samuel D. Faust 《Journal of environmental science and health. Part. B》2013,48(3):325-336
Abstract A modified analytical method employed to determine the insecticide Zectran in natural waters frequently has resulted in erroneous data. The errors have been attributed to interferences from particulate matter in these waters. In order to evaluate analytical interferences due to sorption of Zectran on particu‐lates, a series of experiments was performed using bottom sediments and a peat moss in contact with aqueous solutions of Zectran at a pH value of 6.0 and 20°C. Isotherm studies confirmed that Zectran sorption occurs in a direct relation to the amount of chemically oxidizable carbon present in the bottom sediments or peat moss. However, the extent of sorption was limited, which suggested that particulates may not be the primary interference in the modified analytical method. 相似文献
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Orok Esu Oyo-Ita Inyang Okon Oyo-Ita Samuel Ugim Ugim 《Environmental monitoring and assessment》2013,185(2):1413-1426
Costal sediment samples from Great Kwa River as well as adjoining termite nest and soil samples were analyzed for quantitative determination of polycyclic aromatic hydrocarbons (PAHs) and sterols using gas chromatography–mass spectrometry (GC–MS) in order to access the possibility of transport of biologically produced PAHs/sterols from termite nest to the sediments. The total PAH concentrations (sum of parent and alkyl) for the sediments ranged between 131.96 and 139.35 ng/g dry weight (dw) while those for the nest and soil samples were in the range 9.51–9.71 and 71.85–77.26 ng/g dw, respectively. These levels of PAHs in sediments were relatively low compared to other urban/industrial Asian and American countries. No evidence of the usual biologically produced PAHs was found, thus reducing the likelihood of transport of these compounds from the nest to the sediments. The absence of parent and alkyl PAHs in central compartment of the nest may reflect the selective fern leaves feeding pattern of the dominant termite species prevalent in the vicinity of the study site. Utilization of six selected PAH ratios such as Fla/(Fla + Pyr) (0.4–0.5), Ant/(Ant + Phe) (0.25–0.90), BaA/(BaA + Chrys) (0.45–0.61), MP/P (0.05–6.81), 1,7/(1,7?+?2,6)-DMP (0.61–0.95), and LPAH/HPAH ( 2.80–3.80) allows discrimination of PAH sources for the samples to be made with a mixed source dominance observed. Examination of sterol distributions in the samples shows relatively high abundance of cholest-5-en-3β-ol in central compartment of the nest, considered here as a consequence of metabolic conversion of phyto-/fungi sterols in the tissues of the termite species. The relatively reduced levels of stanol compounds in central compartment of the nest may be associated with their utilization by the termites for growth and development. 相似文献
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The Arribes del Duero area, in western Spain, at the border with Portugal, is suffering a drastic change in the landscape, as a response of the diminution of population. Traditional tasks related to agriculture have been abandoned, and heavy sheep farming on the area is provoking the impoverishment of soils. The effect derived from these actions is the disintegration of the terraces, which are one of the major attractions for tourists visiting the region. We propose that incentives for local people could help to develop those traditional labours to recover the landscape, together with the promotion of immigration of families with school-age children, could bring back the economy to the area. 相似文献