Objectives: The objective of this study was to examine the association between dangerous student car drop-off behaviors and historical child pedestrian–motor vehicle collisions (PMVCs) near elementary schools in Toronto, Canada.
Methods: Police-reported child PMVCs during school travel times from 2000 to 2011 were mapped within 200 m of 118 elementary schools. Observers measured dangerous student morning car drop-off behaviors and number of children walking to school during one day in 2011. A composite score of school social disadvantage was obtained from the Toronto District School Board. Built environment and traffic features were mapped and included as covariates. A multivariate Poisson regression was used to model the rates of PMVC/number of children walking and dangerous student car drop-off behaviors, adjusting for the built environment and social disadvantage.
Results: There were 45 child PMVCs, with 29 (64%) sustaining minor injuries resulting in emergency department visits. The mean collision rate was 2.9/10,000 children walking/year (SD = 6.7). Dangerous drop-off behaviors were observed in 104 schools (88%). In the multivariate analysis, each additional dangerous drop-off behavior was associated with a 45% increase in collision rates (incident rate ratio [IRR] = 1.45, 95% confidence interval [CI], 1.02, 2.07). Higher speed roads (IRR = 1.27, 95% CI, 1.13, 1.44) and social disadvantage (IRR = 2.99, 95% CI, 1.03, 8.68) were associated with higher collision rates.
Conclusions: Dangerous student car drop-off behaviors were associated with historical nonfatal child PMVC rates during school travel times near schools. Some caution must be taken in interpreting these results due small number of events and limitations in the data collection, because collision data were collected historically over a 12-year period, whereas driving behavior was only observed on a single day in 2011. Targeted multifaceted intervention approaches related to the built environment, enforcement, and education could address dangerous drop-off behaviors near schools to reduce child PMVCs and promote safe walking to school. 相似文献
Deep learning (DL) models are increasingly used to make accurate hindcasts of management-relevant variables, but they are less commonly used in forecasting applications. Data assimilation (DA) can be used for forecasts to leverage real-time observations, where the difference between model predictions and observations today is used to adjust the model to make better predictions tomorrow. In this use case, we developed a process-guided DL and DA approach to make 7-day probabilistic forecasts of daily maximum water temperature in the Delaware River Basin in support of water management decisions. Our modeling system produced forecasts of daily maximum water temperature with an average root mean squared error (RMSE) from 1.1 to 1.4°C for 1-day-ahead and 1.4 to 1.9°C for 7-day-ahead forecasts across all sites. The DA algorithm marginally improved forecast performance when compared with forecasts produced using the process-guided DL model alone (0%–14% lower RMSE with the DA algorithm). Across all sites and lead times, 65%–82% of observations were within 90% forecast confidence intervals, which allowed managers to anticipate probability of exceedances of ecologically relevant thresholds and aid in decisions about releasing reservoir water downstream. The flexibility of DL models shows promise for forecasting other important environmental variables and aid in decision-making. 相似文献
The issue of communities and their exposure to bushfire hazard is highly topical internationally. There is a perceived trend of greater exposure to bushfire risk which is exacerbated by increased levels of building in fire-prone areas or peri-urban regions. There is a need to clarify what we understand to be peri-urban regions, and how we conceptualise and describe the communities that reside in them, in order that efficient and effective services are provided. However, more questions arise for us. For example: Where are these communities located? What do we know about the people who live there? What are the implications for bushfire mitigation? Despite being problematic, locality remains important to the understanding of communities, bushfire hazard and delivery of services. 相似文献
The treeline ecotone divides forest from open alpine or arctic vegetation states. Treelines are generally perceived to be temperature limited. The role of herbivores in limiting the treeline is more controversial, as experimental evidence from relevant large scales is lacking. Here we quantify the impact of different experimentally controlled herbivore densities on the recruitment and survival of birch Betula pubescens tortuosa along an altitudinal gradient in the mountains of southern Norway. After eight years of summer grazing in large-scale enclosures at densities of 0, 25, and 80 sheep/km2, birch recruited within the whole altitudinal range of ungrazed enclosures, but recruitment was rarer in enclosures with low-density sheep and was largely limited to within the treeline in enclosures with high-density sheep. In contrast, the distribution of saplings (birch older than the experiment) did not differ between grazing treatments, suggesting that grazing sheep primarily limit the establishment of new tree recruits rather than decrease the survival of existing individuals. This study provides direct experimental evidence that herbivores can limit the treeline below its potential at the landscape scale and even at low herbivore densities in this climatic zone. Land use changes should thus be considered in addition to climatic changes as potential drivers of ecotone shifts. 相似文献
Child protection is an area of police work which has expanded in the last decade, leading to an increase in the number of police officers working in departments which specialise in investigating cases of child abuse. Police officers in this field may be at greater risk of experiencing secondary traumatic stress but there remains a paucity of research in this area of policing. Analogies can be drawn to existing research in policing and with social service workers involved in child protection. The paper finishes off with implications for police forces to ensure safe working environments and appropriate counselling for employees. 相似文献
Private domestic gardens contribute substantially to the biodiversity of urban areas and benefit human health and well-being.
We previously reported a study of 267 gardens across five cities in the United Kingdom in which variation in geographical
and climatic factors had little bearing on the richness, diversity and composition of plant species. We therefore hypothesise
that garden management is an important factor in determining garden characteristics. Here, from the same sample of gardens,
we investigate potential associations between the uses to which people put their gardens, the types of management activities
they undertake, and the characteristics of those gardens. Householders (n = 265) completed a questionnaire detailing various aspects of garden use and management activities. The majority of respondents
used their gardens chiefly for relaxation, recreation, and eating. Fewer than one fifth included “gardening” amongst their
garden uses even though all performed some garden management, suggesting that not all management activity resulted from an
interest in gardening. Garden-watering and lawn-mowing were the most prevalent activities and were predictors of other types
of management including weeding, vegetation-cutting, leaf-collection, and dead-heading flowers. A number of these activities
were associated with one another, the richness and composition of plant species, and the number of land uses in gardens. However,
relationships between management activities and the amount of tall vegetation were less consistent, and garden management
appeared to be independent of garden area. More species of amphibians, birds, and mammals were observed in gardens with ponds
and in which efforts were made to attract wildlife, particularly by providing drinking water. This study supports the hypothesis
that garden use and management is associated with garden characteristics. 相似文献
This paper summarizes the historical and recent research on the aquatic toxicology and bioconcentration potential of tetrabromobisphenol A (TBBPA), a major flame retardant in electronics. Historical studies on TBBPA are presented in detail, and are compared with more recent research. The historical studies have not been published to date, though they were pivotal in regulatory assessments by the European Union, Canada, and the USA. These assessments have enabled the use of TBBPA as a flame retardant in electronic applications, to the present. The studies were conducted under a Test Rule by the US Environmental Protection Agency in 1987, and were sponsored by member companies of the North American Flame Retardants Alliance (NAFRA) through the American Chemistry Council. The studies were conducted under Good Laboratory Practice procedures, and include 6 acute toxicity tests of TBBPA with fish, invertebrates, algae, and microbes, eight chronic tests, and three bioconcentration studies with fish and invertebrates. Methods and empirical data for each study are detailed in an electronic supplement. Results of the NAFRA studies are compared with recent findings on TBBPA toxicity. Molluscan shell growth may be uniquely sensitive to TBBPA, more sensitive than chronic fish or crustacean toxicity endpoints. Several of the NAFRA studies and several independent studies have reported toxicities exceeding the empirical water solubility limits of TBBPA (in the range of 2.0 mg/L depending on pH). The validity of these results is discussed. 相似文献
Summary Glycosidase inhibitors are widespread in plants and can be sequestered by Lepidoptera, for which they can presumably serve as defences by making the insects indigestible to a range of potential predators. As a result of this study of eight British species of moth and butterfly it was found that glycosidase inhibitors in the insects could then be detected in the larval food plants which were not previously known to contain them; however, some were only detectable in the plants after concentration. In some cases the inhibition of specific glycosidases by Lepidoptera was detected even though the insects had not apparently acquired them from their food plants. Inhibition of-N-acetylglucosaminidase was observed in most of the adult Lepidoptera analysed but further work is required to identify the inhibitors, though they are likely to be nitrogen-containing compounds. Weak anti-HIV activity was also observed in the glycosidase-inhibiting fractions ofAcherontia atropos and the plantUrtica dioica.相似文献
Summary Male blue-winged warblers (Vermivora pinus) sing two distinctly different song types (I and II). Type II songs from eastern New York and western Massachusetts, USA, are different (Fig. 1), and during playback experiments males respond stronger to local than to foreign songs (Fig. 2). Type I songs are more stereotyped geographically (Fig. 1), and males do not differentiate between local and foreign Type I songs (Fig. 3). Differing degrees of intra- and inter-sexual selection on these two forms may have promoted variability in Type II songs and stereotypy in Type I songs among locations. 相似文献