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491.
492.
Using the 1993 crash of Amtrak's Sunset Limited in Mobile, Alabama, this study examines the safety education provided by seven newspapers. A total of 117 news stories were analysed for five primary themes: overall story category, passenger safety theme, train personnel safety theme, train safety theme and rescue safety. Sixty-three per cent were found to contain at least one safety theme paragraph within the larger story. A total of 631 paragraphs were identified as safety theme paragraphs, 32 per cent of which were passenger safety themes, 8 per cent were train personnel safety, 31 per cent were train safety and 29 per cent were rescue safety themes. As in previous research, safety themes rarely appeared alone; more often than not, a story contained a mixture of all themes. Some safety themes appeared more frequently than others, but overall, the safety themes present a complete view of the safety issues surrounding the crash.
Safety themes are embedded within a story framework which reflects the three stages of disaster news work. Images of normalcy tragically disrupted by the crash abound as do images of passengers escaping and aiding others. Disaster relief personnel and aviation officials are shown working to restore order and solve the mystery of the crash. Within this framework we can learn what to expect when a train crashes and what we might have to do in a similar situation.  相似文献   
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Studies have shown that pelagic predators do not overlap with their prey at small scales. However, we hypothesized that spinner dolphin foraging would be affected by the spatio-temporal dynamics of their prey at both small and large scales. A modified echosounder was used to simultaneously measure the abundance of dolphins and their prey as a function of space and time off three Hawaiian islands. Spinner dolphin abundance closely matched the abundance patterns in the boundary community both horizontally and vertically. As hypothesized, spinner dolphins followed the diel horizontal migration of their prey, rather than feeding offshore the entire night. Spinner dolphins also followed the vertical migrations of their prey and exploited the vertical areas within the boundary layer that had the highest prey density. Cooperative foraging by pairs of dolphins within large groups was evident. The geometric and density characteristics of prey patches containing dolphins indicate that dolphins may alter the characteristics of prey patches through this cooperative foraging. The overlap of Hawaiian spinner dolphins and their prey at many temporal and spatial scales, ranging from several minutes to an entire night and 20 m to several kilometers, indicates that the availability of truly synoptic data may fundamentally alter our conclusions about pelagic predator-prey interactions.  相似文献   
495.
CORRESPONDENCE     
Charles Kelly 《Disasters》1996,20(3):276-277
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The Florida Bay ecosystem supports a number of economically important ecosystem services, including several recreational fisheries, which may be affected by changing salinity and temperature due to climate change. In this paper, we use a combination of physical models and habitat suitability index models to quantify the effects of potential climate change scenarios on a variety of juvenile fish and lobster species in Florida Bay. The climate scenarios include alterations in sea level, evaporation and precipitation rates, coastal runoff, and water temperature. We find that the changes in habitat suitability vary in both magnitude and direction across the scenarios and species, but are on average small. Only one of the seven species we investigate (Lagodon rhomboides, i.e., pinfish) sees a sizable decrease in optimal habitat under any of the scenarios. This suggests that the estuarine fauna of Florida Bay may not be as vulnerable to climate change as other components of the ecosystem, such as those in the marine/terrestrial ecotone. However, these models are relatively simplistic, looking only at single species effects of physical drivers without considering the many interspecific interactions that may play a key role in the adjustment of the ecosystem as a whole. More complex models that capture the mechanistic links between physics and biology, as well as the complex dynamics of the estuarine food web, may be necessary to further understand the potential effects of climate change on the Florida Bay ecosystem.  相似文献   
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Environmental Science and Pollution Research - The correct destination of waste is an essential factor for sustainable development. Electronic waste, which is very toxic, is the type of waste with...  相似文献   
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Environmental Science and Pollution Research - The sensitivity of anuran to the effects of habitat destruction and contamination has led to a preoccupying global decline in their populations....  相似文献   
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