Economics of "essential use exemptions" for metered-dose inhalers under the Montreal Protocol

The Montreal Protocol on Substances that Deplete the Ozone Layer has led to rapid reductions in the use of ozone-depleting substances worldwide. However, the Protocol provides for "essential use exemptions" (EUEs) if there are no "technically and economically feasible" alternatives. An application that might qualify as an "essential use" is CFC-powered medical metered-dose inhalers (MDIs) for the treatment of asthma and chronic obstructive pulmonary disease (COPD), and the US and other nations have applied for exemptions in this case. One concern is that exemptions are necessary to ensure access to medications for low-income uninsureds. We examine the consequences of granting or withholding such exemptions, and conclude that government policies and private-sector programs are available that make it economically feasible to phase out chlorofluorocarbons (CFCs) in this application, thereby furthering the global public health objectives of the Montreal Protocol without compromising the treatment of patients who currently receive medication by means of MDIs.     

Dams,Floodplain Land Use,and Riparian Forest Conservation in the Semiarid Upper Colorado River Basin,USA

Land and water resource development can independently eliminate riparian plant communities, including Fremont cottonwood forest (CF), a major contributor to ecosystem structure and functioning in semiarid portions of the American Southwest. We tested whether floodplain development was linked to river regulation in the Upper Colorado River Basin (UCRB) by relating the extent of five developed land-cover categories as well as CF and other natural vegetation to catchment reservoir capacity, changes in total annual and annual peak discharge, and overall level of mainstem hydrologic alteration (small, moderate, or large) in 26 fourth-order subbasins. We also asked whether CF appeared to be in jeopardy at a regional level. We classified 51% of the 57,000 ha of alluvial floodplain examined along >2600 km of mainstem rivers as CF and 36% as developed. The proportion developed was unrelated to the level of mainstem hydrologic alteration. The proportion classified as CF was also independent of the level of hydrologic alteration, a result we attribute to confounding effects from development, the presence of time lags, and contrasting effects from flow alteration in different subbasins. Most CF (68% by area) had a sparse canopy (50% canopy cover occupied <1% of the floodplain in 15 subbasins. We suggest that CF extent in the UCRB will decline markedly in the future, when the old trees on floodplains now disconnected from the river die and large areas change from CF to non-CF categories. Attention at a basinwide scale to the multiple factors affecting cottonwood patch dynamics is needed to assure conservation of these riparian forests.     

环境规制对长三角城市绿色发展的影响——基于技术创新的作用路径分析

环境规制与绿色发展的关系及其作用机制是复杂且有争议的议题。基于长三角41个地级及以上城市2003—2018年的面板数据,首先科学构建绿色发展水平测度的指标体系,计算各城市的绿色发展水平及空间动态演变;其次,借鉴可拓展随机性的环境影响评估模型（STIRPAT）,构建面板计量模型,深入探究环境规制对城市绿色发展的影响。研究发现：（1）长三角地区环境规制和绿色发展水平均呈上升趋势,但区域差异显著,绿色发展水平从东南向西北,呈现圈层式递减态势,而环境规制强度重心经历了由东南向西北转移的演变。（2）总体上,环境规制显著影响城市绿色发展,两者间存在倒“U”型关系,即过强的环境规制会抑制城市绿色发展水平的提升。（3）环境规制与技术创新之间存在紧密的联动关系,即环境规制主要通过技术创新这一中介路径促进城市绿色发展转型,其中介效应占总效应的比例约为50.1%。因此,在推动长三角一体化高质量发展过程中,应该根据城市绿色发展效率来制定本地的环境规制,并重视提升本地的技术创新水平,进而实现城市绿色发展转型的目标。     

ASSESSMENT OF METHODS FOR MEASURING EMBEDDEDNESS: APPLICATION TO SEDIMENTATION IN FLOW REGULATED STREAMS1

Abstract: Five commonly used methods for measuring embeddedness the — degree to which fine particles surround coarse substrate on the surface of the streambed — are assessed and used to evaluate the sedimentation pattern resulting from impoundment on tributaries of the Connecticut River. Results show that the U.S. Environmental Protection Agency (USEPA) method best reflects the sediment regime on these rivers. On the Ompompanoosuc River, regulated by a run-of-the-river/flood control dam, embeddedness increases significantly directly downstream of the dam. On the unregulated White River, no downstream trends in embeddedness are observed. The USEPA results on the Ompompanoosuc River reflect the movement of a local decrease in embeddedness, interpreted as a moving region of scour, with a calculated transport rate of approximately 5 to 25 m/day. Observed transport rates are similar to previously measured sediment transport rates and consistent with results from a multifraction sediment transport model. Application of the USEPA method to an additional regulated tributary demonstrates the effects of dam management on embeddedness. Flow regulation with high sediment trapping efficiency results in a decrease in embeddedness downstream of the dam. Results provide insight into the utility of available methods for evaluating the effects of management practice on streambed composition.     

环境规制对碳排放的门槛效应及其区域差异

为了深入探究我国环境规制的政策效应及其区域差异,采用我国30个省区2004—2014年的面板数据（不含港澳台及西藏自治区数据,下同）,分别以能源强度、产业结构和FDI（外商直接投资）作为门槛变量,以环境规制为核心解释变量,利用面板门槛模型分析我国环境规制对碳排放的门槛效应及其在东部、中部和西部存在的区域差异.结果表明:由于能源强度、产业结构、FDI这3个门槛变量的作用,环境规制对碳排放的影响体现出非线性特征,且环境规制的政策效应在东部、中部和西部3个区域内存在较为明显的差异.东部地区的环境规制在3个门槛变量的中低门槛区间均不能促进碳减排,处于高门槛区间时,能源强度会促进碳排放,而产业结构和FDI这两个门槛变量则对碳排放有抑制作用,其中能源强度跨过第2个门槛值（1.111 8）后仍表现出对碳排放的促进作用,产业结构（0.566 1）和FDI（1 159.40×108元）分别跨过第2个门槛值后,对碳排放表现出抑制作用;中部地区在能源强度的影响下,环境规制对碳排放一直为抑制作用,在产业结构和FDI的影响下则一直是促进作用;西部地区的能源强度与碳排放呈倒“U”型关系,两个门槛值分别为1.200 8与2.153 3,以产业结构和FDI为门槛变量时,环境规制均未能发挥碳减排作用,一直体现为促进作用.因此,政府在实施环境规制政策时不能采取一刀切的措施,要根据东部、中部和西部的不同情况针对性地实施相应的环境规制政策.      

基于iTRAQ技术荧蒽降解菌的比较蛋白质组学分析

提取荧蒽不同诱导时间的红球菌BAP-1蛋白,应用iTRAQ技术结合LC-MS/MS对差异蛋白进行聚类以及生物信息学分析,以研究荧蒽高效降解菌的蛋白功能调控机理.结果表明：共鉴定到796个差异蛋白（差异倍数为2）,其中表达上调的有613个,表达下调的有183个.3个比对组（3d/1d、6d/1d和8d/1d）共同差异表达蛋白为111个（上调56个,下调55个）.通过COG、GO富集和pathway富集分析后发现绝大部分差异蛋白参与代谢和能量产生过程.在荧蒽诱导下上调关键蛋白有细胞色素C、三磷酸腺苷合成酶、二磷酸核苷等激酶,还有一些结合蛋白、脱氢酶、核糖体蛋白和趋化性蛋白等;下调显著的是5-甲基四氢蝶酰三谷氨酸-同型半胱氨酸甲基转移酶.这些蛋白共同组成蛋白互作网络调控荧蒽降解菌的一系列生命活动.     

Ecotoxicological Characterisation and Classification of Existing Chemicals

GOAL, SCOPE AND BACKGROUND: In 1998, the International Council of Chemical Associations (ICCA) launched a global initiative to investigate more than 1,000 HPV chemicals (High Production Volume, > or = 1,000 t/a) within the refocused OECD HPV Chemicals Programme. Up to the OECD SIDS Initial Assessment Meeting in April 2004 (SIAM 18) 147 ICCA dossiers (ca. 230 CAS-No) have been assessed based on a harmonised data set. The environmental profile and an ecotoxicological characterisation of these chemicals are presented here. Data for acute aquatic toxicity were correlated among each other, as well as data for fish (LC50, LD50) and rodents (LD50). The data for acute aquatic toxicity are compared with other existing chemicals. METHODS: Data of the ICCA HPV chemicals from the OECD SIAM 11-18 are presented for: log Kow (as an indicator for bioaccumulation potential), biodegradation, acute aquatic toxicity and availability of long-term toxicity data. Correlation analysis was performed with log transformed data and a linear regression model was fitted to the data, if a significant correlation was found. Acute toxicity for fish and acute oral toxicity for rodents were correlated on a molar basis. Acute aquatic toxicity of the chemicals is compared with data from BUA reports 1-234 and a random EINECS sample (Knacker et al. 1995). RESULTS AND DISCUSSION: According to the dossier information, 71 of the 147 ICCA chemicals are not 'readily biodegradable', 21 have a log Kow > or = 3, and 44 are 'toxic' (LC/EC50 < or = 10 mg/L) or 'very toxic' (LC/EC50 < or = 1 mg/L) to aquatic organisms. For 77, only the base set (acute fish, Daphnia and algae) is available, for the rest at least one long-term test (fish or Daphnia) is available and three tests for a mere 14 others. Based on the data presented, the SIAM gives recommendations for Environment and Human Health. 22 chemicals have been identified as a 'candidate for further work' for Environment and 16 for Human Health. The highest correlation coefficient was obtained correlating fish and Daphnia (r2 = 0.79). LC50 (fish) is significantly correlated with LD50 (rodent), but data are widely scattered. The correlation is not improved after transforming LC50 (fish) to LD50 (fish), using BCF QSAR. Based on acute aquatic toxicity, 25.1% of the chemicals from the BUA reports 1-234 are classified as 'very toxic' (LC/EC50 < or = 1 mg/L). This proportion is 2.5-fold higher than the ICCA HPV chemicals and 1.4-fold higher than the random EINECS sample. CONCLUSIONS: Correlation coefficients for aquatic toxicity data are rather uniform (0.57-0.79) compared with literature data, but also the best correlation was observed between fish and Daphnia. Because the scatter around the regression lines is still considerable, simple predictions of ecotoxicity between species are not possible. Correlation of LC50 (fish) and LD50 (rodent) indicates that toxicity is different. Surprisingly, the correlation of fish and rodent toxicity is not improved by transforming LC50 values to internal LD50s. The selection of ICCA chemicals by market significance (production volume) leads to a classification of toxicity, which is more comparable to a random sample of EINECS chemicals than to German BUA chemicals. The latter were chosen for concern (for Environment or Human Health). RECOMMENDATIONS AND OUTLOOK: Of 147 dossiers assessed between SIAM 11-18, ca. 75% were sponsored by the three following countries: Germany (42), USA (37) and Japan (33). The current output is about 50 dossiers per year (70-100 CAS-No), but a trend for an increase of output is noticeable. Industry, national authorities, and OECD work on a further development to speed up the output. The number of chemicals with 'low priority for further work' and the work recommended for the 'candidates' (mainly exposure assessment) indicate that the data presented were adequate for an initial hazard assessment according to OECD requirements. From the ICCA HPV list (n = 880, state of 1999) 44% of the chemicals have data available to cover all SIDS endpoints for Environment and only 33% for Human Health (Allanou et al. 1999). This indicates the importance of the Initiative to provide information on existing chemicals. The authors agree with the expectation "...that the scientific information provided by this global initiative will be considered as an internationally accepted and harmonised basis for further steps of chemicals management." (ICCA 2002 b).     

基于Internet的交通道口事故监测管理系统的研究

传统的道路交通监测存在不足之处 ,相应的路口自动监测力量犹显薄弱。对诸如闯红灯 ,闯单禁行线 ,超速等交通违章行为缺乏现代化的监测、取证等必要手段。笔者提出基于Internet的道路交通违章监测系统 ,有效地利用先进的通信及计算机技术 ,为提高交通道口的管理水平 ,确认违章事故提供了手段 ,并对此系统进行深入地分析和设计 ,同时通过实例证明 ,该系统违章监测和事故确认具有的有效性和可操作性。     

城市公共场所人群拥挤踩踏事故分析

城市公共场所人群高度聚集、流动性大,紧急状态时常发生群死群伤的拥挤踩踏事故,造成大量人员伤亡和恶劣的社会影响。笔者首先提出拥挤踩踏事故分析的一般方法,并用群集指数来表征人群高度聚集这一参量;通过对近年来国内外人群拥挤踩踏事故的分析,认为该类事故以人群高度聚集为条件,由公众造成又危害公众,具有诱因众多、发生突然、难以控制等特点;强调事故预防和控制重点是建立事故应急机制,加强人群的管理和疏导等;同时从公共场所的性能优化设计、人群素质和群集密度、人群管理控制以及信息交流等方面分析其事故原因及提出相应对策,对预防此类事故发生,减少群集伤亡有重要意义。     

石油烃类降解菌在不同矿化度下的生长规律及去油效果研究

研究了不同盐浓度含油废水中石油烃类降解菌的生长情况以及对原油的去除效果。实验结果表明:在盐浓度低于15%的石油烃废水中,降解菌生长旺盛,且数量大;在盐浓度为15%～25%的石油烃废水中有较多菌量,但数量已明显减少;在盐浓度为30%以上的石油烃废水中几乎无细菌生长。培养时间为13h时,去油率可达到55%;随着培养时间的延长,原油去除率趋于平缓。高盐度石油烃废水中生存的微生物在处理含油废水方面具有很大的应用潜力。