我国典型季风海洋型冰川积累区冰雪剖面的环境记录

运用多种方法,对白水1号冰川积累区冰雪剖面的主要阴、阳离子和δ18O的环境意义分析表明,受强烈淋溶作用影响,离子和δ18O的季节变化不明显,剖面离子浓度显著低于雪坑,离子流失量较大。NH4+年际变化最为显著,与丽江降水表现出相同的变化趋势,Mg2+和Ca2+浓度与冰雪剖面净积累量呈反向变化。分析表明,阴离子主要是湿沉降产物,阳离子主要是干沉降产物。该剖面所反映的13年δ18O比率变化介于-11.8‰～-14.6‰。冰雪剖面中δ18O与西南季风指数、冰雪剖面积累量、丽江降水和丽江气温呈反向变化,表现出显著的"降水量效应"。     

天山乌鲁木齐河源1号冰川气溶胶可溶性离子观测与分析研究

基于2003年、2004年和2007年3年内共采集的155个气溶胶样品的分析测试,探讨了天山乌鲁木齐河源1号冰川区气溶胶中可溶性离子的组成及年际变化特征,并对其可能来源进行了分析.结果表明,气溶胶可溶性离子平均浓度为2.759μg·m-3,化学组成以NO-3、SO2-4、Ca2+和CO2-3为主,冰川区大气环境呈碱性.可溶性离子总质量浓度年际变化特征为2007年2004年2003年,主要离子组成没有发生明显变化,但单一离子浓度变化不尽相同,其原因主要与沙尘活动的强弱有关.Ca2+、Na+、Mg2+、CO2-3和Cl-主要可能来自陆源矿物,而NO-3和NH+4很大程度上以人为源为主;并且发现,SO2-4和K+可能同时受陆地源与人类活动来源的影响.通过气团轨迹聚类分析得出,冰川区大气主要受来自西南方、西方及西北方3个方向气团的控制,这些气团均经过伊犁河谷或阿拉山口到达冰川区,其中,在距地面2000 m以下高度传输的气团会带来大量的沙尘物质,影响冰川区大气环境.     

1959-2008年乌鲁木齐河源1号冰川融水径流变化及其原因

采用数理统计、 Morlet小波分析和Mann-Kendall突变检验对乌鲁木齐河源1号冰川1959-2008年径流序列进行分析,揭示了冰川融水径流的变化趋势、 周期特征和突变特性,并对径流与气候、 冰川变化关系进行了探讨。结果表明:乌鲁木齐河源1号冰川近50 a来径流增加趋势显著,特别是在1993年发生突变后,平均径流较1993年前增加了69.4%。径流序列第一主周期为15 a,第二主周期为6 a。在13~16 a时间尺度上看,1号冰川融水径流在未来的几年将继续保持偏多趋势,但是从5~7 a和超长期时间尺度上看则相反。冰川融水径流与冰川物质平衡、 年均气温、 消融期气温及年降水量存在良好的瞬时响应关系,其中消融期气温的振动对冰川融水径流振动能量贡献最大,在气温超过2 ℃时,径流将加速增长。物质平衡变化100 mm可引起河流径流变化22.9×10⁴ m³,1号冰川过去50 a累积物质平衡为-13 693 mm,相当于额外补给河流径流量3 135.7×10⁴ m³,约是年径流量的16.1倍。     

Compliance with Canada’s Fisheries Act: A Field Audit of Habitat Compensation Projects

Loss of fish habitat in North America has occurred at an unprecedented rate through the last century. In response, the Canadian Parliament enacted the habitat provisions of the Fisheries Act. Under these provisions, a “harmful alteration, disruption, or destruction to fish habitat” (HADD) cannot occur unless authorised by Fisheries and Oceans Canada (DFO), with legally binding compensatory habitat to offset the HADD. The guiding principle to DFO’s conservation goal is “no net loss of the productive capacity of fish habitats” (NNL). However, performance in achieving NNL has never been evaluated on a national scale. We investigated 52 habitat compensation projects across Canada to determine compliance with physical, biological, and chemical requirements of Section 35(2) Fisheries Act authorisations. Biological requirements had the lowest compliance (58%) and chemical requirements the highest (100%). Compliance with biological requirements differed among habitat categories and was poorest (19% compliance) in riparian habitats. Approximately 86% of authorisations had larger HADD and/or smaller compensation areas than authorised. The largest noncompliance in terms of habitat area occurred in riverine habitat in which HADDs were, on average, 343% larger than initially authorised. In total, 67% of compensation projects resulted in net losses of habitat area, 2% resulted in no net loss, and 31% achieved a net gain in habitat area. Interestingly, probable violations of the Fisheries Act were prevalent at half of the projects. Analyses indicated that the frequency of probable Fisheries Act violations differed among provinces. Habitat compensation to achieve NNL, as currently implemented in Canada, is at best only slowing the rate of habitat loss. In all likelihood, increasing the amount of authorised compensatory habitat in the absence of institutional changes will not reverse this trend. Improvements in monitoring and enforcement are necessary to move towards achieving Canada’s conservation goals.     

国道318线二郎山西口至康定县城沿线地质灾害发育特征及治理对策

在川藏公路关键段二郎山西口至康定县城长74km的范围内,共发育滑坡34处、崩塌33处、泥石流43处,其发育密度分别达0．46,0．44和0．58个（条）／km。分析表明,上述地质灾害的分布与该地所赋存的地形地貌、地持构造及岩性条件等密切相关。     

Effect of a nurse back injury prevention intervention on the rate of injury compensation claims

Problem

This study evaluated the effect of introducing a No Lifting policy on back injuries to nurses, across an entire health care system.

Methods

Methods included: analysis of the data for all public health agencies in the Australian state of Victoria; compensation data from the Victorian Workcover Authority; data about workforce and program implementation from a retrospective survey of agencies; longitudinal analysis of standardized workers compensation claim rates for back injuries before, during and after the intervention.

Results

A statistically significant decline in back injury claim rates during implementation contrasted with no statistically significant trends within the periods before and after the intervention. A statistically significant reduction occurred in mean quarterly standard back injury claim incidence rates per 1,000 equivalent fulltime nursing staff (EFTNS), representing a 24% reduction in standard back injury claims/1000 EFTNS.

Discussion

Ergonomics principles encourage changing the work environment to suit the worker. This approach delivered a significant improvement in the immediate term.

Impact of industry

The substantial decline in back injury rates signifies a major improvement in the safety of a critical aspect of the work environment for nurses.     

榄普一线500kV线路取消架空地线防雷性能分析

榄普一线500 k V线路由于地线覆冰严重,多次出现线路跳闸、地线断裂等事故,因此需要将架空地线取消。结合行波法和ATP-EMTP电磁暂态分析,对取消地线前后榄普一线的耐雷强度进行了仿真计算。计算结果表明,取消地线后雷击基本都变为绕击,并且绕击耐雷强度和反击耐雷强度均有所降低,需要采用其他防雷措施进行保护。     

城沐一线500kV线路取消架空地线力学性能分析

架空地线的主要作用是防止雷电直击导线,但在冬季,由于架空地线线径较细,强度较低,多次因地线覆冰引发断线、跳闸事故,因此提出了取消重冰区500 k V线路架空地线的做法。使用有限元仿真工具ANSYS Workbench,以城沐一线500 k V线路三基杆塔为对象进行建模,对取消地线前后城沐一线的力学性能做了仿真计算。计算结果表明,在不同的覆冰强度下,取消地线后杆塔塔头及塔身主材所受拉力及应力都有所下降,提高了整个塔线体系在冬季运行的可靠性。结果可为冰区超高压电网的运行维护工作提供指导。     

How to Discredit a Social Movement: Negative Framing of “Idle No More” in Canadian Print Media

The Idle No More (INM) movement entered public view in November 2012 as a grassroots response to Canadian federal legislation Bill C-45, an omnibus bill that reduced environmental protection of lands and waters. Backed by new media technologies, Indigenous activists and their Settler Canadian allies took a series of online and offline actions to bring public attention to Bill C-45’s devastating implications and the socio-economic sufferings of Indigenous people across Canada. This explorative study examines how INM was reported by nine Canadian print media during its initial upsurge from December 2012 to January 2013. A mixed-methods content analysis reveals that although there were numerous supportive voices discussing INM’s contributions to Indigenous self-determination and environmental protection, they were overwhelmed by anti-INM rhetoric advanced by Postmedia Network and its affiliated titles. The study thus highlights the importance of promoting communication and media alternatives for future struggles against capitalism’s appropriation of nature.     

Investigation on the role of traffic volume in accidents on urban highways

Introduction

Roadway safety is a major concern for the general public and public agencies, as roadway crashes claim many lives and cause substantial economic loss each year. In Iran, a large number of vehicles are involved in road accidents each year, which cause many deaths and extensive property damage; such accidents are among the major causes of death and disability in the country. Method: To reduce roadway accidents, the factors that affect the occurrence and severity of accidents should be scrutinized to prevent or reduce their effect. The method that many researchers have adopted to determine the effective parameters surrounding road accidents in recent years is through statistical modeling of accidents. In this article, the role of different kinds of vehicles in traffic flow are investigated separately in terms of the likelihood of crashes on urban highways, and the vehicles are divided into three groups: passenger cars, heavy vehicles, and light non-passenger car vehicles. Poisson and negative binomial (NB) regression models were applied to model the accidents in this research, which were categorized into two groups: no injury (property damage only) accidents and more severe (injury and fatal) accidents. Results: Ultimately, we conclude that light non-passenger car vehicles (i.e., taxis and motorcycles) play the largest role in the occurrence of crashes on urban highways for both types of accidents.