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121.
Introduction: Motorcycles are colloquially referred to as “donorcycles” among medical staff. However, the actual impact of helmet laws and helmet use on organ donation is unknown. Michigan’s 35-year-old universal helmet law (UHL) was repealed in April 2012 and replaced by a partial-helmet law. We hypothesized that there would be an increase in organ donation rates from unhelmeted motorcyclist fatalities. Methods: Michigan's Gift of Life Michigan organ donation database was queried from April 2008 through May 2015 in conjunction with the Michigan Trauma Quality Improvement Program database from the same time period. All in-hospital motorcycle crash fatalities were examined. Results: A three-fold increase was found in the rate of organ donation for unhelmeted motorcyclists compared to helmeted motorcyclists (p = 0.006). Motorcycle crash fatalities tended to be younger in age after the UHL repeal with an average age of 32.8 years versus 40.8, however, this finding was not statistically significant (p = 0.071). Additionally, there was no significant difference in organ donation rates pre-UHL repeal (2008–2012) versus post-repeal (2012–2015). Conclusions: This is the first study to demonstrate an increased rate of organ donation among unhelmeted motorcyclist fatalities compared to helmeted rider fatalities. There was no significant increase in the rate of organ donation following the Michigan UHL repeal. However, we identified that some motorcycle crash fatalities were from illegally unhelmeted riders in the past, prior to the repeal. Practical Application: Unhelmeted motorcyclists are three times more likely than helmeted riders to become organ donors, possibly due to the well documented increase in severe traumatic brain injuries in this population. From a public health perspective, helmets should be required for all motorcyclists and efforts to advocate in favor of helmet legislation should be supported by trauma systems and health professionals. 相似文献
122.
以西部山区的缩影川西为研究对象,利用交通矢量化数据和自然社会经济数据,在GIS软件支持下,探讨"十五"计划以来不同时期川西山区交通通达性与GDP的海拔空间分异性及其相关关系。结果表明:(1)2000~2013年间川西山区交通通达性有了显著提高,各县通达水平两级分化有所减弱,高值区集中于攀西城市群,低值区主要位于甘孜州;(2)川西山区GDP与交通水平均具有较为明显的海拔梯度分异,表现为中低海拔区中海拔区高海拔区高原区,呈现出"反自然梯度特征";(3)从整体上看,川西山区通达性指数与GDP存在显著正向关联且关联程度不断加强,交通主干线显现出更为明显的经济促进作用,而边缘化的地理区位不利于地区对外开放,阻滞了经济发展;(4)不同时期各海拔区交通通达性及其构成要素与GDP的关联方向和程度差异较大。 相似文献
123.
西湖与青山水库底栖动物群落的研究 总被引:4,自引:0,他引:4
通过对杭州市的两个主要水体西湖和青山水库的底栖动物群落包括种类组成、优势种群、生物量等的比较研究。西湖和青山水库底栖动物群落主要由寡毛类和摇蚊幼虫组成 ,存在适应低溶氧、耐有机污染的种群。从底栖动物群落生态学角度评价了西湖和青山水库水体的营养化程度。 相似文献
124.
入湖溪流对西湖富营养化的影响调查 总被引:1,自引:0,他引:1
陆莹 《环境监测管理与技术》2000,(Z1)
分析了西湖水质现状 ,指出入湖溪流的水质不佳是目前西湖保持富营养化状态的重要原因。提出了相应的对策建议。 相似文献
125.
Meliker JR Slotnick MJ Avruskin GA Haack SK Nriagu JO 《Environmental geochemistry and health》2009,31(1):147-157
Arsenic concentrations exceeding 10 μg/l, the United States maximum contaminant level and the World Health Organization guideline
value, are frequently reported in groundwater from bedrock and unconsolidated aquifers of southeastern Michigan. Although
arsenic-bearing minerals (including arsenian pyrite and oxide/hydroxide phases) have been identified in Marshall Sandstone
bedrock of the Mississippian aquifer system and in tills of the unconsolidated aquifer system, mechanisms responsible for
arsenic mobilization and subsequent transport in groundwater are equivocal. Recent evidence has begun to suggest that groundwater
recharge and characteristics of well construction may affect arsenic mobilization and transport. Therefore, we investigated
the relationship between dissolved arsenic concentrations, reported groundwater recharge rates, well construction characteristics,
and geology in unconsolidated and bedrock aquifers. Results of multiple linear regression analyses indicate that arsenic contamination
is more prevalent in bedrock wells that are cased in proximity to the bedrock-unconsolidated interface; no other factors were
associated with arsenic contamination in water drawn from bedrock or unconsolidated aquifers. Conditions appropriate for arsenic
mobilization may be found along the bedrock-unconsolidated interface, including changes in reduction/oxidation potential and
enhanced biogeochemical activity because of differences between geologic strata. These results are valuable for understanding
arsenic mobilization and guiding well construction practices in southeastern Michigan, and may also provide insights for other
regions faced with groundwater arsenic contamination. 相似文献
126.
关于中国西部“山川秀美”再造的思考——兼论西部生态安全建设中的防灾减灾 总被引:1,自引:0,他引:1
再造一个“山川秀美”的大西北 ,展现出一幅理想的人与自然依存的场景。笔者为此给出独特的思考和科学的见解 :要实现这一目标 ,必须研讨“山川秀美”的科学内涵 ,以恢复大西北自然生态安全环境为基础 ,以防灾减灾 ,保护人与自然为手段 ,依靠科技进步 ,坚持可持续发展战略 ,从长远利益并结合地区实际 ,才能真正实现人与自然和谐共存的“山川秀美” 相似文献
127.
西部大开发与聚落生态建设——以西南山区为例 总被引:2,自引:0,他引:2
陈国阶 《生态与农村环境学报》2001,17(2):5-8
我国西部生态环境退化与广泛分布的农村聚落落后的生产方式和生活方式有密切关系。在西部大开发中 ,搞好生态环境必须与聚落建设统一规划 ,同步实施。重点应解决好环境恶劣的聚落、地方病聚落、自然保护区聚落、草场聚落、工程移民聚落。根据不同生态状况 ,可采取新建聚落、重建聚落与迁建聚落等聚落建设方略 相似文献
128.
为促进西部大开发战略的实施和西部地区可持续发展 ,就西部地区环境政策框架和环境管理能力建设两方面进行了初步研究 ,提出了一些建议 相似文献
129.
This paper analyzes livelihood change and livelihood sustainability of households in the upland part of the Lembang subwatershed,
West Sumatra, in response to changes in the natural resource management context during the last decade. Using the sustainable
livelihood framework (SLF), we measured livelihood changes at two separate points in time, 1996 and 2006, and assessed their
environmental, economic, social, and institutional sustainability. We found that people with a low income had less access
to capital assets than people from middle- and high-income groups. Our analysis revealed, however, that access to capital
assets increased over time, and that poor households experienced economic improvement, indicating an overall increase in economic
sustainability. Environmental sustainability, however, is threatened by intensive agricultural practices such as high agrochemical
input and intensive soil tillage on steep slopes, leading to pollution and soil erosion. Social sustainability is also a matter
of concern: while social exclusion has been reduced, income inequity has increased. Institutional sustainability is likely
to remain uncertain, as local institutions for natural resource management are still weak, despite the fact that decentralization
has been implemented during the last 8 years. External facilitation is needed to improve the livelihood of upland people while,
at the same time, enhancing the sustainability of watershed management. Strengthening local institutions, conserving natural
resources, and promoting environmentally sound agricultural practices are the three most important policies to be promoted
within the watershed. 相似文献
130.
Robert A. Montgomery C. Nichole Rubeck-Schurtz Kelly F. Millenbah Gary J. Roloff Mark E. Whalon Larry G. Olsen 《Environmental management》2009,44(1):12-23
In the United States, environmental regulatory agencies are required to use “best available” scientific information when making
decisions on a variety of issues. However, agencies are often hindered by coarse or incomplete data, particularly as it pertains
to threatened and endangered species protection. Stakeholders often agree that more resolute and integrated processes for
decision-making are desirable. We demonstrate a process that uses species occurrence data for a federally endangered insect
(Karner blue butterfly), a readily available habitat modeling tool, and spatially explicit information about an important
Michigan commodity (tart cherries). This case study has characteristics of many protected species regulatory decisions in
that species occurrence data were sparse and unequally distributed; regulatory decisions (on pesticide use) were required
with potentially significant impacts on a viable agricultural industry; and stakeholder relations were diverse, misinformed,
and, in some situations, unjustly contentious. Results from our process include a large-scale, empirically derived habitat
suitability map for the focal species and a risk ranking of tart cherry orchards with risk based on the likelihood that pesticide
applications will influence the focal protected species. Although the majority (77%) of pesticide-influence zones overlapped
Karner blue butterfly habitat, risk scores associated with each orchard were low. Through our process we demonstrated that
spatially explicit models can help stakeholders visualize and quantify potential protected species effects. In addition, model
outputs can serve to guide field activities (e.g., species surveys and implementation of pesticide buffer zones) that help
minimize future effects. 相似文献