MicroRNAs and their role in environmental chemical carcinogenesis

Environmental Geochemistry and Health - MicroRNAs (miRNAs) are a class of small, noncoding RNA species that play crucial roles across many biological processes and in the pathogenesis of major...     

Identifying human-induced influence on microbial community: A comparative study in the effluent-receiving areas in Hangzhou Bay

Microbial compositions showed high differences in two study areas. COD was the key anthropogenic indicator in the coastal wastewater disposal area. Distinctive microbes capable of degrading toxic pollutants were screened. Microbial communities in effluent-receiving areas followed “niche theory”. Microbial community structure is affected by both natural processes and human activities. In coastal area, anthropegenetic activity can usually lead to the discharge of the effluent from wastewater treatment plant (WWTP) to sea, and thus the water quality chronically turns worse and marine ecosystem becomes unhealthy. Microorganisms play key roles in pollutants degradation and ecological restoration; however, there are few studies about how the WWTP effluent disposal influences coastal microbial communities. In this study, sediment samples were collected from two WWTP effluent-receiving areas (abbreviated as JX and SY) in Hangzhou Bay. First, based on the high-throughput sequencing of 16S rRNA gene, microbial community structure was analyzed. Secondly, several statistical analyses were conducted to reveal the microbial community characteristics in response to the effluent disposal. Using PCoA, the significant difference of in microbial community structure was determined between JX and SY; using RDA, water COD and temperature, and sediment available phosphate and ammonia nitrogen were identified as the key environmental factors for the community difference; using LDA effect size analysis, the most distinctive microbes were found and their correlations with environmental factors were investigated; and according to detrended beta-nearest-taxon-index, the sediment microbial communities were found to follow “niche theory”. An interesting and important finding was that in SY that received more and toxic COD, many distinctive microbes were related to the groups that were capable of degrading toxic organic pollutants. This study provides a clear illustration of eco-environmental deterioration under the long-term human pressure from the view of microbial ecology.     

Enhancing short-term ethanol-type fermentation of waste activated sludge by adding saccharomycetes and the implications for bioenergy and resource recovery

Ethanol-type sludge fermentation has recently attracted much attention because it can enhance direct interspecies electron transfer and thus improve the anaerobic digestion of waste activated sludge(WAS). In this paper, the enhancement of short-term ethanol-type fermentation of WAS via adding Saccharomyces was investigated. The experimental results show that the maximum ethanol production of 1030.8 ± 20.6 mg/L was achieved, with the optimum fermentation conditions of a p H of 5.1, temperature of...     

底质耗氧行为探讨

本文介绍了底质耗氧速率方程，速率常数ｋ值比较及温度对ｋ值的影响等，对南排污河等底质的研究表明：ｋ值大，污染严重，故可用ｋ值估计底质污染的轻重。另外，温度升高，底质耗氧速率常数增大。     

对现代城市防洪的一些思考

城市现代化建设和经济的快速发展，及随之日益增长的城市洪涝灾害损失，对现代城市防洪工作提出了更高的要求，体现了城市防洪的重要性。探讨了现代城市防洪工作的内涵，和应采用的先进防洪技术。     

Evaluation of attachment of Cryptosporidium parvum and Giardia lamblia to soil particles

Transport of Cryptosporidium parvum oocysts and Giardia lamblia cysts in the aquatic environment is poorly understood. Information about their transport is essential for actual risk assessment and development of effective control practices. Several studies have suggested that attachment to soil particles is not likely to occur, but the hypothesis has not been well tested, partly because enumeration of C. parvum oocysts or G. lamblia cysts [written as (oo)cysts] in the presence of soil has been difficult. In this paper, a combination of flow cytometry, and epifluorescence and confocal microscopy was successfully used to enumerate (oo)cysts in the presence of soil and determine whether (oo)cysts travel freely in water or attached to soil particles. The maximum soil concentration in water samples for reliable enumeration of (oo)cysts was 2 mg/L. Particle attachment experiments detected attached pairs of oppositely charged beads and (oo)cysts, while no attachment was observed between like charged beads, (oo)cysts, and soil particles. These results support the hypothesis that electrostatic forces govern the interaction between (oo)cysts and soil particles. Batch experiments further confirmed the null hypothesis (p > 0.05) that (oo)cysts do not attach to natural soil particles. These findings suggest that, when (oo)cysts have been entrained in overland flow (i.e., runoff), they will travel freely in the water and not as part of the particulate sediment load.     

湿式氧化法预处理甲基氯化物废水

研究了反应时间，进水pH，反应温度以及氧分压对湿式氧化法预处理甲基氯化物生产废水的影响。在不调节废水的pH，反应温度180℃，氧分压1.5MPa，反应时间60min的最佳操作条件下，COD，有机磷，有机硫的去除率分别达到68.5%,65%,88%,出水的BOD5/COD由0.107提高至0.36。预处理后废水的厌氧可生化性得到很大的改善，COD的去除率提高20%-30%左右，产甲烷量增加1.6-2.1倍。     

胆汁引流对黑熊体毛中微量元素含量的影响

作者在1990年6～7月采集了胆汁引流黑熊和未手术黑熊的体毛样本,经原子吸收光谱仪和极谱仪测定。结果表明,胆汁引流黑熊雌雄之间体毛中 Se、Zn、Fe、Mg、Cu、Mn、Ca、P 含量差异不显著;胆汁引流1年的黑熊与未手术黑熊相比,体毛中 Ca 含量明显降低、Mn 含量明显增高。因此,在配制黑熊饲料时应重视矿物质的添加量,以提高熊胆产量和质量。     

四川省南充市大气中多环芳烃的分布

用超声波萃取，抽滤，减压蒸发浓缩，硅胶柱净化，再逍缩至干，定客溶解的方法处理了南充市5个监测点冬，夏季乘集的大气颗粒物样品，然后用高效液相色谱法分析其中9种多环芳烃含量，大气中苯并[a]芘的年平均含量为31．5ng/m3，略低于成都市1988年测定的年平均值，南充市大气中多环芳烃的主要来源是居民生活用煤，其次是汽车尾气，改变燃料结构，集中供热，加强城市交通管理，是减少多环芳烃污染的途径。