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501.
Lam LT 《Journal of Safety Research》2005,36(2):181-187
INTRODUCTION: This cross-sectional community-based randomized telephone survey, aimed to compare the parental risk perceptions on childhood pedestrian road safety among three different major community language speaking groups and the mainstream English speaking Australians in Sydney, Australia. METHOD: This was a community-based telephone survey with subjects randomly selected from the population of specific cultural languages in Sydney. RESULTS: Results indicated that Chinese and Arabic speaking parents or caregivers perceived the road environments as significantly less hazardous for their 4-12 year old children as pedestrians when compared with Vietnamese and English speaking parents. This was true even after adjusting for the age of child, socioeconomic status, and the living environments of respondents. CONCLUSION: The implication of the results was discussed in light of possible application to childhood safety behavior across different cultures. IMPACT TO THE INDUSTRY: The results obtained have highlighted the importance of cultural factors in risk perceptions, and safety behaviors. Cultural differences in risk perceptions should be taken into consideration in the design of safety education programs. 相似文献
502.
Steven W. Effler Charles F. Carter 《Journal of the American Water Resources Association》1987,23(2):243-249
ABSTRACT: Short-circuiting of the inflow occurs from the Seneca River across the southern portion of Cross Lake, New York. Spatial differences in thermal stratification, transparency and light attenuation, and net sedimentation are documented for the lake. The depth of the epilimnion was generally deeper, and the temperature gradient in the metalimnion was at times lower, at a deep-water location proximate to the short-circuiting zone, than at a position more remote from the inflow. Transparency was generally lower, and light attenuation greater, proximate to the short-circuiting zone, indicating the contribution of attenuating components from the river. The net sedimentation rate in the short-circuiting zone was greater and temporally more irregular than for a deep-water position remote from the river inflow. The spatial differences in the physical characteristics and processes in Cross Lake are attributable to the magnitude and position of the inflow from the Seneca River. 相似文献
503.
Uranov (1975) formulated a theory of the age structure of plant populations and, in particular, defined the index of ageness . On the basis of this theory, the concepts of the energy efficiency of plants in a certain ontogenetic state and the average efficiency of a population () are introduced. A new classification of populations with respect to the types of age structure is proposed which is based on both the and values and, accordingly, is named the delta–omega classification. The notion of effective population density is defined. This parameter takes into account different loads of plants in different ontogenetic states on the environment and is quantitatively equal to the product of the population density and . The proposed approaches and methods are illustrated by data on the distribution of age states in different plant species. 相似文献
504.
Dr. Claire Julian-Reynier Geneviève Macquart-Moulin Jean-Paul Moatti Yvette Aurran Françoise Chabal Ségolène Aymé 《黑龙江环境通报》1994,14(9):859-864
More than 10 years after a chromosomal anomaly screening programme was set up in France for pregnant women of advanced age, amniocentesis is still a controversial issue. The reasons why eligible women did not utilize the test and whether or not the existence of social welfare coverage determined women's access to prenatal diagnosis were studied. A group of 291 women aged ⩾35 years who recently gave birth to normal liveborns was interviewed by telephone. Among those aged 38 years and over, who automatically qualified for social security coverage, 75 per cent had undergone amniocentesis as opposed to 23 per cent in the 35 to 37-year-old non-covered age group who did not qualify for social security coverage. In both groups, access to amniocentesis was found to depend on the physicians', women's and male partners' attitudes towards prenatal diagnosis and abortion. Among the younger group, the uptake depended mainly on socio-economic factors. Institutional policies should ensure greater equality of access while allowing for individual preferences. 相似文献
505.
The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic
plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system
to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of
the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative
frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions
from a statewide database, and scaled values were totaled for the AMCI value. AMCI values were grouped and tested by ecoregion
and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic
plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood
Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments,
Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general
water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or
benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower
quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values
reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially
have low nutrient levels. 相似文献
506.
淮南矿区不同塌陷年龄积水区环境效应分析 总被引:2,自引:0,他引:2
采煤塌陷水域是淮南矿区一种特殊的地表水体。文章选择矿区不同塌陷年龄的塌陷水域,监测分析其水质理化指标和重金属元素。结果表明:塌陷水域环境状况因塌陷年龄和周边环境差异而不同,具有季节性变化。水域受到了不同程度的污染,部分理化指标随时间增长有累计效应。与国家地表水质量标准比较,水域重金属元素除了Hg严重超标外,其它As、Se、Cd、Cr、Cu、Pb、Zn等均不超标,未对塌陷水域构成重金属污染。通过对不同塌陷水域环境效应进行分析与评价,可为其综合利用提供一定的理论依据。 相似文献
507.
Emissions from industrial activities pose a serious threat to human health and impose the need for monitoring both inorganic and organic pollutants in industrial areas.We selected Masson pine (Pinus massoniana L.) as potential biomonitor and collected the current (C) and previous year (C+1) needles from three industrial sites dominated by petrochemical,ceramics manufacturing,and iron and steel smelting plants and one remote site to determine heavy metals (Cu,Cd,Pb,Zn,Cr,Ni and Co) and polycyclic aromatic hydrocarbons (PAHs) in unwashed and water-washed needles.Both unwashed and washed C+1 needles showed generally higher concentrations of heavy metals and PAHs than C needles,although the washed needles more clearly spotlighted the accumulation effect of PAHs over exposure time.Water-washing resulted in a significant decrease in needle PAH concentrations with more significant effects shown in C needles.By contrast,needle heavy metal concentrations were much less affected by washing.Although heavy metals and PAHs might differ in adsorption and uptake strategies,their higher concentrations in the needles at the industrial sites indicated conspicuous contamination due to industrial emissions there,The PAH distribution patterns in pine needles accorded with the real types of energy consumption in the study sites and were efficiently used for pinpointing local pollutant sources. 相似文献
508.
本研究检测分析了我国吉林省伊通满族自治县(YT)、湖南省怀化市(HH)、四川省甘孜藏族自治州(GZ)3个城市5个年龄段(≥60、50~59、40~49、30~39、20~29岁)人体混合血清中六溴苯(hexabromobenzene,HBB)、五溴甲苯(pentabromotoluen,PBT)、五溴苯(pentabromophenyl,PBBz)、四溴对二甲苯(tetrabromo-p-xylene,PTBX)等4种新型溴代阻燃剂(NBFRs)的含量水平.PBBz、PBT和HBB在人体血清中的检出率为100%.在3个城市中,NBFRs总含量、HBB含量、PBT含量、PBBz含量(除GZ外)均在年轻人群中有升高的趋势.在5个年龄段中,YT和HH均有明显的主要污染物,但GZ首要污染物不明显且4种NBFRs含量占比在5个年龄段中基本稳定.3个城市人体血清中NBFRs在5个年龄段中的组成分布呈现出不同的趋势,表明不同地区的污染来源不同.其中,工业较为发达地区(YT和HH)人体血清中NBFRs总含量高于欠发达地区(GZ)的水平. 相似文献
509.
宿松-枞阳断裂最新活动时代及未来地震危险性研究 总被引:1,自引:0,他引:1
宿松—枞阳断裂卫星影像清晰,是一条对构造、地貌、中新生代盆地有着控制意义的断裂。本文对该断裂所处的区域地震地质构造背景进行了分析,结合断裂的发育历史,选择典型剖面,对断裂的最新活动特征进行调查。根据野外地质考察和断裂沿线地震活动统计结果,对断裂未来的地震危险性进行了定量评估。分析认为,该断裂晚第四纪以来仍然有所活动,但活动强度已减弱,未来可能发生无地表位错的中强地震,最大震级综合判定为M5.5。 相似文献
510.
为在综合考虑长期风化导致的污染物释放变化、区域气候条件差异、以及参数不确定性影响下,精细评估飞灰道路基材资源化利用过程对浅层地下水资源(在饮用水质量方面)潜在风险及其时空分异特性,提出了一种综合的基于风险的方法,可用于评估碱性废料(如焚烧飞灰)部分替代公路垫层材料的回收潜力.将估算源浓度的浸出试验结果与风险评估程序中通常采用的归趋-迁移模型相结合,通过实验室浸出试验模拟未风化和风化条件下的污染物释放,采用Monte Carlo方法模拟参数不确定性对风险的影响,针对不同气候特征对环境风险区域特性的影响进行评估.结果显示:在华北地区典型气候条件下,所识别的7种目标污染物中,Zn、Cd和Pb存在暴露点预测浓度超标的可能,超标概率分别为34%、96%和7%,导致其暴露浓度(以95%分位值表征)均超标,环境风险不可忽视;碳酸化作用会使得部分污染物的溶出特性发生变化,并导致长期风险的变化,具体到碳酸化后的暴露浓度,Cd呈下降趋势,Ni和Zn基本不变或变化较小,Cr、Cu、As明显增加但仍显著低于标准限值,而Pb离子暴露浓度显著增加的同时超标情况从1倍增加到3.5倍,需要引起重点关注;由于降雨等区域差异化参数的影响,不同区域之间风险差异较大,差异最大的干旱区和半干旱区暴露浓度相差近2倍;不同区域超标的共性污染物为Zn和Cd,另外,湿润/半湿润区域还存在Pb暴露浓度超标. 相似文献