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71.
Objective: The purpose of this study was to determine the feasibility of modifying the Ticking Aggressive Cars and Trucks (TACT) program, originally designed to work on state highways, within a metropolitan area to reduce unsafe interactions and their related crashes between drivers of large trucks and passenger vehicles.

Methods: Using crash data, the driving behaviors most commonly associated with large truck and passenger vehicle crashes were identified. A public awareness campaign using media messaging and increased law enforcement was created targeting these associated behaviors. The frequency of these behaviors both before and after the public awareness campaign was determined through observation of traffic at 3 specific locations within the city. Each location had a sufficient volume of large truck and passenger traffic to observe frequent interactions. Pre- and postintervention data were compared using negative binomial regression with generalized estimating equations to evaluate whether the campaign was associated with a reduction in the identified driving behaviors.

Results: A comparison between crash data from before, during, and after the campaign and crashes during the same time periods in previous years did not show a significant difference (P =.081). The number of large trucks observed in traffic remained the same during pre- and postintervention periods (P =.625). The rates of negative interactions per 100 large trucks decreased for both large trucks and passenger vehicles after the intervention, with calculated rate ratios of 0.58 (95% confidence interval [CI], 0.48, 0.70) and 0.31 (95% CI, 0.20, 0.47). The greatest reduction was seen in passenger vehicles following too close, with a rate ratio of 0.21 (95% CI, 0.15, 0.30).

Conclusions: Although designed for reducing crashes on highways, the TACT program can be an effective approach for improving driver behaviors on city streets.  相似文献   

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The invasive caprellid amphipod Caprella mutica is one of the most widely dispersed marine non-native species globally. Originating in sub-boreal north-east Asia, it has now been found in both the northern and the southern hemispheres. One potential reason why this species is such a successful invader is its ability to utilise a wide variety of food sources. The contribution of different food sources to the diet of C. mutica was estimated using fatty acids as biomarkers. Caprella mutica was collected from three field sites, including sea cages stocked with Atlantic salmon Salmo salar, shellfish longlines stocked with the blue mussel Mytilus edulis and mooring lines marking the Loch Linnhe Artificial Reef (>2 km from caged finfish aquaculture), where established populations of this species are known to occur. In addition, the fatty acid compositions of C. mutica held in aquaria and either fed the microalga, Dunaliella tertiolecta, or the diatom, Phaeodactylum tricornutum, for a period of 21 days were investigated. The fatty acid composition of the diatom and the microalgal diets was also examined. The results showed that C. mutica contained high levels of polyunsaturated fatty acids, particularly 20:5(n-3); other dominant fatty acids included 18:1(n-9), 22:6(n-3) and 16:0 (in decreasing order based on abundance). Significant differences in the fatty acid profiles between caprellids fed on the microalgae and the diatom diets and between C. mutica collected from the field sites were observed. These results provide evidence that lipid biomarkers can be successfully used to provide evidence of feeding strategy for C. mutica and that the flexibility observed in this strategy may play an important role in its invasion success.  相似文献   
74.
Knowledge on how divers exploit the water column vertically in relation to water depth is crucial to our understanding of their ecology and to their subsequent conservation. However, information is still lacking for the smaller-bodied species, due mostly to size constraints of data-loggers. Here, we report the diving behaviour of a flying diving seabird, the Cape Cormorant Phalacrocorax capensis, weighing 1.0–1.4 kg. Results were obtained by simultaneously deploying small, high resolution and high sampling frequency GPS and time-depth loggers on birds breeding on islands off Western South Africa (34°S, 18°E) in 2008. In all, dive category was assigned to all dives performed by 29 birds. Pelagic dives occurred almost as frequently as benthic dives. Pelagic dives were shallow (mean: 5 m) and took place over seafloors 5–100 m deep. Benthic dives were deeper, occurring on seafloors mainly 10–30 m deep. Dive shape was linked to dive category in only 60% of dives, while the descent rate, ascent rate and bottom duration/dive duration ratio of a dive best explained its dive category. This shows that only the concomitant use of tracking and depth tags can adequately classify diving strategies in a diver like the Cape Cormorant. Diet was mainly Cape Anchovy Engraulis encrasicolis, suggesting that birds probably displayed two contrasted strategies for capturing the same prey. Flexible foraging techniques represent an important key to survival inside the highly productive but heterogeneous Benguela upwelling ecosystem.  相似文献   
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Recent Italian laws mandate the consideration of environmental factors in local plans, especially at the provincial level of government. The plan for the province of Cremona in northern Italy illustrates the integration of the environment in provincial-level planning. The Cremona plan was developed through an ecological planning approach that occurred from 1994 to 1998. As part of this process, the planning team designed an environmental sustainability index. This index was integrated with an environmental capability analysis. To improve the quality of the Cremona landscape, the planning team developed an ecological network. This network seeks to weave together the natural areas of the province, especially by connecting provincial parks to regional river parks throughout Lombardy. The experience of the Cremona provincial plan has implications for environmental management elsewhere in Italy, Europe, and abroad.  相似文献   
78.
ABSTRACT: Recent regulations require impact statements for major water development projects, including reservoirs that will be used for water supply, recreation, and pollution control. A water quantity/quality model was developed and used for making water quality projections of a proposed reservoir in Montgomery County, Maryland. The study area is uncommon in that there is an extensive water quality data base. The results indicate that land use changes will have a significant effect on water quality and that the proposed reservoir will improve the quality of the surface waters downstream from the reservoir. A major effect of land use changes is the increase in the variability of water quality.  相似文献   
79.
ABSTRACT. We investigated the relationships between levee damage and woody corridor along a 353‐mile segment of the Missouri River in Missouri during the flood of 1993. Results indicated that woody corridors between riverbanks and primary levees played a significant role in the reduction or prevention of flood related damage to levees. Forty‐one percent of levee failures in this segment occurred in areas with no woody corridor, while 74 percent and 83 percent of failures occurred where woody corridor widths were less than 300 feet and less than 500 feet, respectively. Median failure lengths with a woody corridor present were 50.3 percent shorter than median failure lengths with no woody corridor present. Levees without failures had significantly wider median woody corridor widths than levees that failed. Eligibility for the Corps of Engineers levee maintenance program was not a significant factor in the reduction of levee damage. Discontinuities in woody corridors played a role in 27.5 percent of the levee failures in the study segment. Smaller segments of the river valley were studied to determine if geomorphic differences influenced variations in the protective value of woody corridors.  相似文献   
80.
The targeting of environmental policies holds the key to their effectiveness and value for money. In this paper we look specifically at the targeting of the various agri‐environmental schemes likely to be on offer to UK farmers under a reformed Common Agricultural Policy. The manner in which these schemes are targeted—at groups of farmers or areas of land—and the precision with which target groups or target land is identified will be critical in their success or failure. One approach is to target the farming systems thought most environmentally sensitive. This avoids drawing lines on a map and may allow policy makers to channel money into the hands of economically disadvantaged farmers or those vulnerable to policy change. But there is also a need for a more radical and geographically‐targeted approach if problems like soil erosion and aquifer protection—requiring drastic land use shifts within specified areas—are to be tackled effectively. We assess the scope for using existing datasets to identify land that should be targeted under an American‐style Conservation Reserve Programme in the UK.  相似文献   
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