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31.
A pedestrian safety education film titled And Keep on Looking and aimed at children ages 9 to 12 was evaluated in several cities. The results showed an increase in safe street crossing knowledge among 9- to 12-year-old Connecticut children who viewed the film, and some improvement in safe street crossing behavior among 9- to 12-year-old Seattle, Washington, children. Crash reduction was assessed in a 2-year, citywide field test conducted in Milwaukee. The field test indicated a crash reduction of more than 20% for 9- to 12-year-old children in Milwaukee compared with children in areas surrounding Milwaukee and children in comparison cities.  相似文献   
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Several writers on animal ethics defend the abolition of most or all animal agriculture, which they consider an unethical exploitation of sentient non-human animals. However, animal agriculture can also be seen as a co-evolution over thousands of years, that has affected biology and behavior on the one hand, and quality of life of humans and domestic animals on the other. Furthermore, animals are important in sustainable agriculture. They can increase efficiency by their ability to transform materials unsuitable for human consumption and by grazing areas that would be difficult to harvest otherwise. Grazing of natural pastures is essential for the pastoral landscape, an important habitat for wild flora and fauna and much valued by humans for its aesthetic value. Thus it seems that the environment gains substantially when animals are included in sustainable agricultural systems. But what about the animals themselves? Objections against animal agriculture often refer to the disrespect for animals’ lives, integrity, and welfare in present intensive animal production systems. Of the three issues at stake, neither integrity nor animal welfare need in principle be violated in carefully designed animal husbandry systems. The main ethical conflict seems to lie in the killing of animals, which is inevitable if the system is to deliver animal products. In this paper, we present the benefits and costs to humans and animals of including animals in sustainable agriculture, and discuss how to address some of the ethical issues involved.  相似文献   
33.
Alkaline tailings from a salt work and a soda plant have been pumped into the southernmost part of Traunsee at Ebensee for many decades. A survey in 1981 showed an accumulation of more than 3 × 106 m3 alkaline mud in the Bay of Ebensee and the existence of slumping structures and turbidites in the profundal zone of the lake. A new survey of the industrial tailings has been performed in 1999. Compared to the earlier survey, the accumulation in the Bay of Ebensee has grown to >4 × 106 m3, which suggests an average yearly input of 90 000 m3. Slumping structures and turbidites document the unstable situation of the tailings near the waste inlet. The lake area occasionally affected by the turbidity currents in the profundal zone has increased to 19%. Within the central profundal area these tailings reach <1 m in thickness.  相似文献   
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Automated Supercritical Fluid Extraction (SFE), using CO2, was tested and optimised for routine analysis of hydrocarbons (THC), polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) in marine sediments. The aim of the exercise was to reduce the amount of solvents used and to reduce the manual handling time for each sample. The sediments contained elemental sulphur, which was removed during the extraction step using activated Cu. Similar recoveries and reproducibility where found for THC when conventional solvent extractions and SFE where compared. Modifying the CO2 with methanol was necessary to obtain extraction recoveries similar to conventional extraction methods for PCB and PAH.  相似文献   
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The quality of the waste sampling procedure and chemical analysis was evaluated in a research program on characterization of organic waste obtained after disc screening of source-separated organic household waste. The sampling procedures focused on a truckload of waste and involved several steps of subsampling including shredding, mixing, blending, high-speed-blending, drying and milling prior to analysis of the organic waste with respect to ash content, crude fibers, crude fat, crude protein, sugar, starch, enzyme-digestible organic matter, P, N, C, H, S and calorific value. The statistical evaluation of the procedures involved 10 samples of the same truckload of waste obtained by splitting the sample at each level in the procedure according to a staggered, incomplete nested statistical design. Furthermore, one sample was analysed six times over a period of approximately one year. The statistical evaluation showed that no single step in the sampling procedure contributed with excessive variance and that the variance caused by the sampling procedure was approximately the same as the variance in the chemical analysis observed over a year. The variance varied with the analytical parameter but for most parameters the uncertainty was satisfactorily low (of the order of 3-10% expressed as the relative standard deviation, which is considered to be satisfactory for waste characterization).  相似文献   
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Automobile insurance claims were examined to determine the rates of neck injuries in rear-end crashes for vehicles with and without redesigned head restraints, redesigned seats, or both. Results indicate that the improved geometric fit of head restraints observed in many newer vehicle models are reducing the risk of whiplash injury substantially among female drivers (about 37% in the Ford Taurus and Mercury Sable), but have very little effect among male drivers. New seat designs, such as active head restraints that move upward and closer to drivers' heads during a rear impact, give added benefit, producing about a 43% reduction in whiplash injury claims (55% reduction among female drivers). Estimated effects of Volvo's Whiplash Injury Prevention System and Toyota's Whiplash Injury Lessening design were based on smaller samples and were not statistically significant.  相似文献   
38.
Concentrations in human placenta of 11 essential elements (P, Ca, Mg, Cu, S, Na, Fe, Zn, K, Se, Mn) and 5 toxic elements (Ba, Sr, Pb, Ni, Cd) are compared for each of two arctic communities in eastern Norway and western Russia, and for another in each country located at more southerly latitudes. All but Mg, Fe, P and K were present in higher concentrations in the Russian study group. The observed inter-element correlations are reflected by the four major factors identified in a principal component analysis. The total variation explained was 67.3%, of which more than half (35.3%) was contributed by Factor 1. P, Ca, Mg, Ba, Sr, Pb, and Ni were major contributors to this factor. The placental concentrations of these elements depended strongly on gestational age, increasing from about week 35 and peaking near weeks 39 and 40, and exhibited skewed frequency distributions and a dependence on maternal smoking. The gestational-dependent mineralization of the placenta is interpreted to reflect the deposition of metal phosphates coinciding with smoking-induced tissue damage. The loadings of the remaining three factors are reviewed in the context of common uptake mechanisms, similar biochemistries and unique transport pathways. The inter-element relationships and grouping of the elements observed should constitute a scientific base for the use of placenta composition in environmental monitoring and epidemiological studies.  相似文献   
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