The presence of Genogroup II Norovirus in Retail Shellfish from Seven Coastal Cities in China

Noroviruses (NoVs) are commonly occurring pathogens that cause gastroenteritis. Outbreaks of viral diseases have often been ascribed to the consumption of contaminated shellfish. Our objective was to evaluate the presence and contamination levels of NoV in shellfish sold at seafood markets in China. We tested 840 shellfish samples (Crassostrea gigas, Mytilus edulis, Azumapecten farreri, SinoNoVacula constricta, Scapharca subcrenata, Ruditapes philippinarum) that were collected from seven cities around the Yellow and Bohai Seas in China between December 2009 and November 2011. We used real-time RT-PCR to detect NoV in purified concentrates from the stomach and digestive diverticula of these shellfish. NoV was detected in 19.35 % (N = 155), 16.67 % (N = 114), 5.70 % (N = 158), 8.82 % (N = 136), 13.74 % (N = 131), and 16.44 % (N = 146) of oyster, mussel, scallop, razor clam, ark shell, and clam samples, respectively. The average detection rate was 13.33 % (112/840). Nucleotide sequencing of the NoV RT-PCR products demonstrated that all strains belonged to NoV genotype GII.12, except two that belonged to GI.3. More than 10² copies of the NoV genome were detected in 69 of 112 positive shellfish samples. Our results suggest that ~13 % of shellfish harbor NoV, and GII.12 NoV is the primary strain in shellfish purchased at markets in seven coastal cities in China.     

Determining reference conditions for TN, TP, SD and Chl-a in eastern plain ecoregion lakes, China

Establishing the nutrient reference condition(baseline environmental condition) of lakes in an ecoregion is a critical consideration in the development of scientifically defensible aquatic nutrient criteria.Three methods were applied to determine reference conditions in the Eastern plain ecoregion lakes with respect to total phosphorus(TP),total nitrogen(TN),planktonic chlorophyll a(Chl-a) and Secchi depth(SD).The reference condition value for the lakes in the Eastern plain ecoregion by the trisection method is TP of 0.029 mg/L,TN of 0.67 mg/L,Chl-a of 3.92 mg/m 3,SD of 0.85 m,and the reference condition range by the lake population distribution approach is TP of 0.014-0.043 mg/L,TN of 0.360-0.785 mg/L,Chl-a of 1.78-4.73 mg/m 3,SD of 0.68-1.21 m.Additionally,empirical models were developed for estimating the reference Chl-a concentration and SD successfully for lakes in the Eastern plain ecoregion.Overall,the data suggest that multiple methods can be used to determine reference conditions and that in Eastern plain ecoregion lakes the reference condition corresponds to a mesotrophic status.     

计量经济模型在我国环境问题研究中的应用评述

通过梳理已有文献,从空间分布、指标选取、主要方法应用频率、数据预处理及结果对比等方面对计量经济模型在我国环境问题研究中的应用现状与不足进行评述,同时提出相应的建议,以期为相关的拓展研究提供参考。     

不同香蒲种植密度对模拟污水的净化试验研究

在不同种植密度处理下,研究香蒲净化污染水体的去除效果。结果表明：种植密度和处理效果成正比,密度为27株/㎡时,净化效果最好,氨氮、TP、TN的去除率分别为94．81％、77．42％、82．84％。     

Another outlook to sector-level energy consumption in Pakistan from dominant energy sources and correlation with economic growth

Environmental Science and Pollution Research - The present study seeks to investigate the sector-level energy consumption of oil and natural gas and to explore the linkage between economic growth,...     

Analyzing the determinants of clean energy consumption in a sustainability strategy: evidence from EU-28 countries

Environmental Science and Pollution Research - The current global spirit for sustainable development has led to increased attention to reducing the use of conventional energy sources and managing...     

Simultaneous carbon and nitrogen removal by anaerobic ammonium oxidation and denitrification under different operating strategies

Environmental Science and Pollution Research - Real domestic wastewater was treated initially in a sequencing batch reactor (SBR), with partial nitrification achieved before the effluent was used...     

延迟焦化装置非密闭除焦工序职业病危害程度分析

目的 了解延迟焦化装置非密闭除焦工序职业病危害程度.方法 选取某大型炼化企业延迟焦化装置一套,通过现场调查,确定非密闭式除焦工序存在的主要职业病危害因素及其接触岗位,对职业病危害因素进行检测,评判并分析各岗位化学有害因素职业接触水平,确定职业病危害程度.结果 除焦工岗位接触硫化氢、粉尘危害因素检测结果超标,装车工接触粉尘危害因素检测结果超标.除焦工硫化氢、粉尘接触水平均为Ⅳ级,装车工粉尘接触水平为Ⅳ级.结论 加强延迟焦化装置非密闭除焦工序个人使用的职业病防护用品的配备,新建延迟焦化装置应尽量选择密闭除焦技术,当前运行的存在非密闭除焦工序的延迟焦化装置应进行工艺技术改造.