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1.
Objective: There have been substantial reductions in motor vehicle crash–related child fatalities due to advances in legislation, public safety campaigns, and engineering. Less is known about non-traffic injuries and fatalities to children in and around motor vehicles. The objective of this study was to describe the frequency of various non-traffic incidents, injuries, and fatalities to children using a unique surveillance system and database.

Methods: Instances of non-traffic injuries and fatalities in the United States to children 0–14 years were tracked from January 1990 to December 2014 using a compilation of sources including media reports, individual accounts from families of affected children, medical examiner reports, police reports, child death review teams, coroner reports, medical professionals, legal professionals, and other various modes of publication.

Results: Over the 25-year period, there were at least 11,759 events resulting in 3,396 deaths. The median age of the affected child was 3.7 years. The incident types included 3,115 children unattended in hot vehicles resulting in 729 deaths, 2,251 backovers resulting in 1,232 deaths, 1,439 frontovers resulting in 692 deaths, 777 vehicles knocked into motion resulting in 227 deaths, 415 underage drivers resulting in 203 deaths, 172 power window incidents resulting in 61 deaths, 134 falls resulting in 54 deaths, 79 fires resulting in 41 deaths, and 3,377 other incidents resulting in 157 deaths.

Conclusions: Non-traffic injuries and fatalities present an important threat to the safety and lives of very young children. Future efforts should consider complementary surveillance mechanisms to systematically and comprehensively capture all non-traffic incidents. Continued education, engineering modifications, advocacy, and legislation can help continue to prevent these incidents and must be incorporated in overall child vehicle safety initiatives.  相似文献   

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Mineralization studies of natural steroid hormones (e.g., 17β-estradiol, E2) are performed in environmental incubators, usually under a constant temperature such as 20°C. In this paper, we present a microcosm protocol that quantified the mineralization of E2 in soils under field temperatures. The nine agricultural soils tested had a wide range of soil organic carbon (1.1 to 5.2%) and clay (9 to 57%) contents. The calculated time over which half of the applied E2 was mineralized (E2-½) ranged from 299 to 910 d, and total E2 mineralization at 48 d (E2-TOT48) ranged from 4 to 13%. In subsequent laboratory incubations, the same soils were incubated under a constant temperature of 20°C, as well as under cyclic temperatures of 14.5°C (14 h) and 11.5°C (10h), which was within the temperature extremes observed in the field microcosms. E2-½ ranged from 157 to 686 d at 20°C and from 103 to 608 d at the cyclic temperatures, with the E2-TOT48 ranging from 6 to 21% at 20°C and from 7 to 30% under cyclic temperatures. Despite the overall 6.75°C lower mean temperatures under the cyclic versus constant temperatures, E2 mineralization was stimulated by the temperature cycles in three soils. Regardless of the incubation, the same loamy sand soil always showed larger E2 mineralization than the other eight soils and this loamy sand soil also had the smallest E2 sorption. Current modeling approaches do not take into consideration the effects of temperature fluctuations in the field because the input parameters used to describe degradation are derived from laboratory incubations at a constant temperature. Across the eight soils, E2-½ was on average 1.7 times larger and E2-TOT48 was on average 0.8 times smaller under field temperatures than under a constant 20°C. Hence, we conclude that incubations at 20°C give a reasonable representation of E2 mineralization occurring under field conditions to be expected in a typical Prairie summer season.  相似文献   
4.
Water resources are increasingly impacted by growing human populations, land use, and climate changes, and complex interactions among biophysical processes. In an effort to better understand these factors in semiarid northern Utah, United States, we created a real‐time observatory consisting of sensors deployed at aquatic and terrestrial stations to monitor water quality, water inputs, and outputs along mountain to urban gradients. The Gradients Along Mountain to Urban Transitions (GAMUT) monitoring network spans three watersheds with similar climates and streams fed by mountain winter‐derived precipitation, but that differ in urbanization level, land use, and biophysical characteristics. The aquatic monitoring stations in the GAMUT network include sensors to measure chemical (dissolved oxygen, specific conductance, pH, nitrate, and dissolved organic matter), physical (stage, temperature, and turbidity), and biological components (chlorophyll‐a and phycocyanin). We present the logistics of designing, implementing, and maintaining the network; quality assurance and control of numerous, large datasets; and data acquisition, dissemination, and visualization. Data from GAMUT reveal spatial differences in water quality due to urbanization and built infrastructure; capture rapid temporal changes in water quality due to anthropogenic activity; and identify changes in biological structure, each of which are demonstrated via case study datasets.  相似文献   
5.
Limited toxicity data are available for estuarine and marine species and the widely used pyrethroid insecticide, permethrin. This study determined acute effects of permethrin on survival, lipid peroxidation, acetylcholinesterase activity, and splenocyte proliferation for two fish species found in South Carolina estuaries; juvenile red drum (Sciaenops ocellatus) and adult mummichog (Fundulus heteroclitus). Juvenile S. ocellatus were significantly more sensitive than adult F. heteroclitus to permethrin exposure, with a 96-h LC50 value of 8 μg/L determined for red drum compared to 23 μg/L for mummichog. Lipid peroxidation activity of the liver increased in permethrin-treated fish compared to control animals after 24 h and decreased after 96 h. Permethrin had no effect on acetylcholinesterase activity of the brain at the concentrations tested. Permethrin exposure significantly inhibited splenocyte proliferation, indicating an immunosuppressive effect. Most of the effects of permethrin on fish cellular stress enzymes and survival occurred at concentrations much higher than those typically measured in the environment. However, inhibition of splenocyte proliferation in juvenile red drum occurred at approximately twice that of measured permethrin concentrations in surface water. These findings may prove useful to the future management and regulation of pyrethroid insecticide use near estuarine habitats.  相似文献   
6.
To facilitate forest planning and management on National Wildlife Refuges, we synthesized multiple data sources to describe land ownership patterns, land cover, landscape pattern, and changes in forest composition for four ecoregions and their associated refuges of the Upper Midwest. We related observed patterns to ecological processes important for forest conservation and restoration, with specific attention to refuge patterns of importance for forest landbirds of conservation priority. The large amount of public land within the ecoregions (31–80%) suggests that opportunities exist for coarse and meso-scale approaches to conserving and restoring ecological processes affecting the refuges, particularly historical fire regimes. Forests dominate both ecoregions and refuges, but refuge forest patches are generally larger and more aggregated than in associated ecoregions. Broadleaf taxa have increased in dominance in the ecoregions and displaced fire-dependent taxa such as pine (Pinus spp.) and other coniferous species; these changes in forest composition have likely also affected refuge forests. Despite compositional changes, larger forest patches on refuges suggests that they may provide better habitat for area-sensitive forest landbirds of mature, compositionally diverse forests than surrounding lands if management continues to promote increased patch size. We reason that although fine-scale research and monitoring for species of conservation priority is important, broad scale (ecoregional) assessments provide crucial context for effective forest and wildlife management in protected areas.  相似文献   
7.
Environmental Science and Pollution Research - Polychlorinated biphenyls (PCBs) are toxic organic compounds and pose serious threats to environment and public health. PCBs still exist in different...  相似文献   
8.
ABSTRACT: Maryland officials have identified stormwater utilities as a potential method of financing programs to control nutrients in urban stormwater runoff that are proposed in Maryland's Chesapeake Bay Nutrient Reduction Plan. This paper reviews a number of issues related to the equity, efficiency and acceptability of user charge schemes. Overall, charges are found to be preferable to property taxes from both equity and efficiency perspectives. In addition, evidence suggests that elected officials will support creation of utilities. Obstacles to the implementation of utilities are identified.  相似文献   
9.
Environmental planners often propose tourism as a means of financing programmes to protect significant environmental areas. Surveys of tourists can provide useful information about the significance of environmental problems, trade-offs among policy objectives, willingness to pay (WTP) for protection programmes and preferences for different payment mechanisms. In Khanh Hoa Province, the provincial People's Committee, the Ministry of Fisheries and the World Conservation Union are working to implement Viet Nam's first marine protected area (MPA) in Nha Trang Bay. This paper reports the results of a survey of local and other Vietnamese and foreign tourists to islands that will be included in the MPA. The majority of respondents thought rubbish on the beaches, water pollution and vendors on beaches were problems and that the MPA was a good idea. Foreign tourists were significantly more likely to perceive environmental problems than were Vietnamese tourists, and persons who agreed there were environmental problems were significantly more likely to support the concept of an MPA, despite the potential for possible economic effects with distributive consequences. WTP for protection was modest and positively correlated with education and income. Although foreign tourists were on average willing to pay more, a larger proportion of Vietnamese tourists were willing to pay some amount to support the MPA. Analyses indicate that changes in income and education expected with economic development will increase both awareness of problems and WTP for protection. The results of this analysis are both encouraging and cautionary. The need for an MPA is clearly recognized by most tourists, and most tourists are willing to pay small fees to support the MPA. Given that education has significant impacts on both perceptions of problems and WTP, educational programmes may be an effective strategy for managing the competing objectives of protection and use.  相似文献   
10.
ABSTRACT: Many hydrologic models have input data requirements that are difficult to satisfy for all but a few well-instrumented, experimental watersheds. In this study, point soil moisture in a mountain watershed with various types of vegetative cover was modeled using a generalized regression model. Information on sur-ficial characteristics of the watershed was obtained by applying fuzzy set theory to a database consisting of only satellite and a digital elevation model (DEM). The fuzzy-c algorithm separated the watershed into distinguishable classes and provided regression coefficients for each ground pixel. The regression model used the coefficients to estimate distributed soil moisture over the entire watershed. A soil moisture accounting model was used to resolve temporal differences between measurements at prototypical measurement sites and validation sites. The results were reasonably accurate for all classes in the watershed. The spatial distribution of soil moisture estimates corresponded accurately with soil moisture measurements at validation sites on the watershed. It was concluded that use of the regression model to distribute soil moisture from a specified number of points can be combined with satellite and DEM information to provide a reasonable estimation of the spatial distribution of soil moisture for a watershed.  相似文献   
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