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291.
The "choking game" is defined as self-strangulation or strangulation by another person with the hands or a noose to achieve a brief euphoric state caused by cerebral hypoxia. Participants in this activity typically are youths (Andrew & Fallon, 2007). Serious neurologic injury or death can result from engaging in this activity. Recent news media reports have described numerous deaths among youths attributed to the choking game. Because no traditional public health dataset collects data on this practice, CDC used news media reports to estimate the incidence of deaths from the choking game. This report describes the results of that analysis, which identified 82 probable choking-game deaths among youths aged 6-19 years during 1995-2007. Seventy-one (86.6%) of the decedents were male, and the mean age was 13.3 years. Parents, educators, and health-care providers should become familiar with warning signs that youths are playing the choking game (Urkin & Merrick, 2006). Impact of industry: By learning about the risk factors for and warning signs of the choking game, parents, educators, and health-care providers may be able to identify youth at risk for playing the game and prevent future deaths. 相似文献
292.
Wai Yeung Yan Prathees Mahendrarajah Ahmed Shaker Kamil Faisal Robin Luong Mohamed Al-Ahmad 《Environmental monitoring and assessment》2014,186(12):8161-8173
This studypresents a remote sensing application of using time series Landsat satellite images for monitoring the Trail Road and Nepean municipal solid waste (MSW) disposal sites in Ottawa, Ontario, Canada. Currently, the Trail Road landfill is in operation; however, during the 1960s and 1980s, the city relied heavily on the Nepean landfill. More than 400 Landsat satellite images were acquired from the US Geological Survey (USGS) data archive between 1984 and 2011. Atmospheric correction was conducted on the Landsat images in order to derive the landfill sites’ land surface temperature (LST). The findings unveil that the average LST of the landfill was always higher than the immediate surrounding vegetation and air temperature by 4 to 10 °C and 5 to 11.5 °C, respectively. During the summer, higher differences of LST between the landfill and its immediate surrounding vegetation were apparent, while minima were mostly found in fall. Furthermore, there was no significant temperature difference between the Nepean landfill (closed) and the Trail Road landfill (active) from 1984 to 2007. Nevertheless, the LST of the Trail Road landfill was much higher than the Nepean by 15 to 20 °C after 2007. This is mainly due to the construction and dumping activities (which were found to be active within the past few years) associated with the expansion of the Trail Road landfill. The study demonstrates that the use of the Landsat data archive can provide additional and viable information for the aid of MSW disposal site monitoring. 相似文献
293.
Robert K. Hall David Guiliano Sherman Swanson Michael J. Philbin John Lin Joan L. Aron Robin J. Schafer Daniel T. Heggem 《Environmental monitoring and assessment》2014,186(4):2413-2433
Prioritizing total maximum daily load (TMDL) development starts by considering the scope and severity of water pollution and risks to public health and aquatic life. Methodology using quantitative assessments of in-stream water quality is appropriate and effective for point source (PS) dominated discharge, but less so in watersheds with mostly nonpoint source (NPS) related impairments. For NPSs, prioritization in TMDL development and implementation of associated best management practices should focus on restoration of ecosystem physical functions, including how restoration effectiveness depends on design, maintenance and placement within the watershed. To refine the approach to TMDL development, regulators and stakeholders must first ask if the watershed, or ecosystem, is at risk of losing riparian or other ecologically based physical attributes and processes. If so, the next step is an assessment of the spatial arrangement of functionality with a focus on the at-risk areas that could be lost, or could, with some help, regain functions. Evaluating stream and wetland riparian function has advantages over the traditional means of water quality and biological assessments for NPS TMDL development. Understanding how an ecosystem functions enables stakeholders and regulators to determine the severity of problem(s), identify source(s) of impairment, and predict and avoid a decline in water quality. The Upper Reese River, Nevada, provides an example of water quality impairment caused by NPS pollution. In this river basin, stream and wetland riparian proper functioning condition (PFC) protocol, water quality data, and remote sensing imagery were used to identify sediment sources, transport, distribution, and its impact on water quality and aquatic resources. This study found that assessments of ecological function could be used to generate leading (early) indicators of water quality degradation for targeting pollution control measures, while traditional in-stream water quality monitoring lagged in response to the deterioration in ecological functions. 相似文献
294.
Reconnecting to the Biosphere 总被引:3,自引:0,他引:3
Folke C Jansson A Rockström J Olsson P Carpenter SR Chapin FS Crépin AS Daily G Danell K Ebbesson J Elmqvist T Galaz V Moberg F Nilsson M Osterblom H Ostrom E Persson A Peterson G Polasky S Steffen W Walker B Westley F 《Ambio》2011,40(7):719-738
Humanity has emerged as a major force in the operation of the biosphere, with a significant imprint on the Earth System, challenging social-ecological resilience. This new situation calls for a fundamental shift in perspectives, world views, and institutions. Human development and progress must be reconnected to the capacity of the biosphere and essential ecosystem services to be sustained. Governance challenges include a highly interconnected and faster world, cascading social-ecological interactions and planetary boundaries that create vulnerabilities but also opportunities for social-ecological change and transformation. Tipping points and thresholds highlight the importance of understanding and managing resilience. New modes of flexible governance are emerging. A central challenge is to reconnect these efforts to the changing preconditions for societal development as active stewards of the Earth System. We suggest that the Millennium Development Goals need to be reframed in such a planetary stewardship context combined with a call for a new social contract on global sustainability. The ongoing mind shift in human relations with Earth and its boundaries provides exciting opportunities for societal development in collaboration with the biosphere--a global sustainability agenda for humanity. 相似文献
295.
Sustainable development is forward-looking; it is a continuous mission for future developments of human society. A genuinely sustainable society is one that initiates developments in sustainable ways. The development of a genuinely sustainable society is supported by its citizens who think and act according to a recognized code of conduct - the sustainable culture. Similar to other forms of culture, sustainable culture of a society is not static, but changes over time. The changes found in a sustainable culture are reflections of the status of sustainability in a society and these changes should be measured from time to time. The resulting measurement gives very important information for decision-makers, in the government and in the private sector, to examine the magnitude of changes that have taken place in a given period of time. The results will also enable them to review and adjust policies in order to better accommodate changes according to the trends of society.This paper provides a method – the T-model, to investigate and measure the extent of change of sustainable culture through two extensive surveys among participants of the construction industry of Hong Kong. The change in sustainable culture is reflected by the change in attitude and practice among construction participants, this can be found in their performance in project development, design and construction operations. The data of these changes are collected and converted to numerical scores. The T-model synthesized these scores and revealed the change of sustainable culture within the specific study time frame. 相似文献
296.
Urban dwellers depend on the generation of ecosystem services for their welfare. The city of Stockholm is growing, and a 25% increase in population is projected by 2030. The effects of urban development were estimated through the quantification of nitrogen (N) leakage to the Baltic Sea under two urban development scenarios. We found that total net N load will increase by 6% or 8%, depending on which growth scenario is applied, and population increase by itself will contribute at least 15% of the point source N leakage. Technical improvements in sewage treatment could, according to our results, decrease total N load to the Baltic Sea by 4%. Based on our results, we conclude that proactive measures such as spatial urban planning can provide a constructive tool for sustainable urban development on regional as well as national and international scales, depending on geographical context as well as the ecosystem services' scale of operation. 相似文献
297.
Helen M. Neville Douglas R. Leasure Daniel C. Dauwalter Jason B. Dunham Robin Bjork Kurt A. Fesenmyer Nathan D. Chelgren Mary M. Peacock Charles H. Luce Daniel J. Isaak Lee Ann Carranza Jon Sjoberg Seth J. Wenger 《Conservation biology》2020,34(2):482-493
Population viability analysis (PVA) is a powerful conservation tool, but it remains impractical for many species, particularly species with multiple, broadly distributed populations for which collecting suitable data can be challenging. A recently developed method of multiple-population viability analysis (MPVA), however, addresses many limitations of traditional PVA. We built on previous development of MPVA for Lahontan cutthroat trout (LCT) (Oncorhynchus clarkii henshawi), a species listed under the U.S. Endangered Species Act, that is distributed broadly across habitat fragments in the Great Basin (U.S.A.). We simulated potential management scenarios and assessed their effects on population sizes and extinction risks in 211 streams, where LCT exist or may be reintroduced. Conservation populations (those managed for recovery) tended to have lower extinction risks than nonconservation populations (mean = 19.8% vs. 52.7%), but not always. Active management or reprioritization may be warranted in some cases. Eliminating non-native trout had a strong positive effect on overall carrying capacities for LCT populations but often did not translate into lower extinction risks unless simulations also reduced associated stochasticity (to the mean for populations without non-native trout). Sixty fish or 5–10 fish/km was the minimum reintroduction number and density, respectively, that provided near-maximum reintroduction success. This modeling framework provided crucial insights and empirical justification for conservation planning and specific adaptive management actions for this threatened species. More broadly, MPVA is applicable to a wide range of species exhibiting geographic rarity and limited availability of abundance data and greatly extends the potential use of empirical PVA for conservation assessment and planning. 相似文献
298.
Maguire RO Kleinman PJ Dell CJ Beegle DB Brandt RC McGrath JM Ketterings QM 《Journal of environmental quality》2011,40(2):292-301
Managing manure in reduced tillage and forage systems presents challenges, as incorporation by tillage is not compatible. Surface-applied manure that is not quickly incorporated into soil provides inefficient delivery of manure nutrients to crops due to environmental losses through ammonia (NH3) volatilization and nutrient losses in runoff, and serves as a major source of nuisance odors. An array of technologies now exist to facilitate the incorporation of liquid manures into soil with restricted or minor soil disturbance, some of which are new: shallow disk injection; chisel injection; aeration infiltration; pressure injection. Surface banding of manure inforages decreases NH3 emissions relative to surface broadcasting, as the canopy can decrease wind speed over the manure, but greater reductions can be achieved with manure injection. Soilaeration is intended to hasten manure infiltration, but its benefits are not consistent and may be related to factors such as soildrainage characteristics. Work remains to be done on refining its method of use and timing relative to manure application, which may improve its effectiveness. Placing manure under the soil surface efficiency by injection offers much promise to improve N use efficiency through less NH3 volatilization, reduced odors and decreased nutrient losses in runoff, relative to surface application. We identified significant gaps in our knowledge as manyof these technologies are relatively new, and this should help target future research efforts including environmental, agronomic, and economic assessments. 相似文献
299.
Chazdon RL Chao A Colwell RK Lin SY Norden N Letcher SG Clark DB Finegan B Arroyo JP 《Ecology》2011,92(6):1332-1343
We develop a novel statistical approach for classifying generalists and specialists in two distinct habitats. Using a multinomial model based on estimated species relative abundance in two habitats, our method minimizes bias due to differences in sampling intensities between two habitat types as well as bias due to insufficient sampling within each habitat. The method permits a robust statistical classification of habitat specialists and generalists, without excluding rare species a priori. Based on a user-defined specialization threshold, the model classifies species into one of four groups: (1) generalist; (2) habitat A specialist; (3) habitat B specialist; and (4) too rare to classify with confidence. We illustrate our multinomial classification method using two contrasting data sets: (1) bird abundance in woodland and heath habitats in southeastern Australia and (2) tree abundance in second-growth (SG) and old-growth (OG) rain forests in the Caribbean lowlands of northeastern Costa Rica. We evaluate the multinomial model in detail for the tree data set. Our results for birds were highly concordant with a previous nonstatistical classification, but our method classified a higher fraction (57.7%) of bird species with statistical confidence. Based on a conservative specialization threshold and adjustment for multiple comparisons, 64.4% of tree species in the full sample were too rare to classify with confidence. Among the species classified, OG specialists constituted the largest class (40.6%), followed by generalist tree species (36.7%) and SG specialists (22.7%). The multinomial model was more sensitive than indicator value analysis or abundance-based phi coefficient indices in detecting habitat specialists and also detects generalists statistically. Classification of specialists and generalists based on rarefied subsamples was highly consistent with classification based on the full sample, even for sampling percentages as low as 20%. Major advantages of the new method are (1) its ability to distinguish habitat generalists (species with no significant habitat affinity) from species that are simply too rare to classify and (2) applicability to a single representative sample or a single pooled set of representative samples from each of two habitat types. The method as currently developed can be applied to no more than two habitats at a time. 相似文献
300.
基于供应链和可拓决策的食品安全预警模型及其应用 总被引:2,自引:0,他引:2
为提高食品安全预警能力,改善食品安全状况,以食品原料供应环境质量、生产加工、流通加工、销售食品质量、食品安全管理与监测作为食品安全预警的关键因素,提出一种基于供应链和可拓决策的食品安全预警模型。从供应链的角度建立食品安全预警指标体系,确定食品安全的经典域、节域和预警对象;建立食品安全预警模型并给出食品安全预警的方法和步骤;结合A省2010年的食品安全数据,定量评价A省食品安全预警状态,结合模型评价结果进行单指标和综合安全预警分析,验证该模型的合理性和适用性。研究结果表明:针对食品安全状况与预警特征,运用基于供应链和可拓决策的食品安全预警模型,能够对食品安全状态进行快速判断并有效预警。 相似文献