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This study investigated the effects of urban concrete materials, of different particle sizes, immersed in water through a laboratory-based experiment. Water was sourced from a high conservation-value wetland (Blue Mountains upland swamp). Prior to the experiment, wetland water was dilute (32.5 μS/cm), acidic (pH 5.3) and had detectable major ion concentrations of only sodium and chloride. Water was exposed to three treatments of different concrete fragment sizes (whole, crushed and fine). All treatments increased conductivity and pH and also resulted in modified ionic composition where calcium, potassium, hydroxide, carbonate and sulphate were recorded at much high levels. The extent and speed of water chemistry changes was linked to the particle size of the concrete. The results of this study support the hypothesis that concrete can be an environmentally hazardous material influencing water quality in urban catchments.  相似文献   
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Water quality of rivers that received coal mine wastes from four active and three closed mines were investigated, focusing on ecologically hazardous pollutants. Zinc and nickel concentrations were highest downstream of two closed mines, particularly from the Canyon mine that closed 20 years earlier. Coal mine wastes increased nickel concentrations in waterways by an average of 25 times. The average concentration of zinc increased below mines waste discharges from 8.6 µg/L (upstream) to 83.4 µg/L (downstream). All coal mine discharges increased river salinity. Salinity increased by more than 6 times (upstream mean 101.4–741.7 µS/cm downstream). This study provides a reminder that water pollution from coal mines is a major environmental issue for both active and closed mines. The study highlights the need for more stringent and consistent environmental regulation for all mines, including key hazardous pollutants from wastes emerging from both active and closed mines.  相似文献   
3.
While virtual reality environments have been shown to reduce pain, the precise mechanism that produces the pain attenuating effect has not been established. It has been suggested that it may be the ability to command attentional resources with the use of head mounted displays (HMDs) or the interactivity of the environment. Two experiments compared participants’ pain ratings to high and low levels of electrical stimulation while engaging in interactive gaming with an HMD. In the first, gaming with the HMD was compared to a positive emotion induction condition; and in the second experiment the HMD was compared to a condition in which the game was projected onto a wall. Interactive gaming significantly reduced numerical ratings of painful stimuli when compared to the baseline and affect condition. However, when the two gaming conditions were directly compared, they equally reduced participants’ pain ratings. These data are consistent with past research showing that interactive gaming can attenuate experimentally induced pain and its effects are comparable whether presented in a head mounted display or projected on a wall.  相似文献   
4.
Objectives: Little is known about psychological factors associated with tobacco use in persons with spinal cord injuries and disorders (SCI&D). Method: Veterans with SCI&D who were current or past smokers were mailed survey questions about physical dependence on nicotine, motivation to smoke, readiness to quit, and use of tobacco cessation methods. Results: Of 684 respondents, 19% were current smokers. They were younger (Ms = 56.4 vs. 63.3 years; p  相似文献   
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