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881.

Introduction  

In 2003, the Japan International Cooperation Agency carried out a development feasibility study of Klaipeda Seaport (Lithuania). The focus in this study was the evaluation of environmental impacts of the port expansion because it is located in an ecologically sensitive area. While the Japanese researchers focused on the environmental impact analysis, they did not provide unambiguous conclusions. The problems remained unresolved and required further, more detailed consideration and deeper analysis.  相似文献   
882.

Introduction  

The present study was part of a comprehensive weight-of-evidence approach with the goal of identifying potential causes for the declines in fish populations, which have been observed during the past decades in the Upper Danube River.  相似文献   
883.
Knowledge about the prevalence and diversity of antibiotic resistance genes in soil bacteria communities is required to evaluate the possibility and ecological consequences of the transfer of these genes carried by genetically modified (GM) plants to soil bacteria. The neomycin phosphotransferase gene (nptII) conferring resistance to kanamycin and neomycin is one of the antibiotic resistance genes commonly present in GM plants. In this study, we investigated kanamycin-resistant (Km(R)) and neomycin-resistant (Nm(R)) soil bacterial populations in a 3-year field trial using a commercial GM corn (Zea mays L.) carrying the nptII gene and its near isogenic line. The results showed that a portion (2.3 - 15.6 %) of cultivable soil bacteria was naturally resistant to kanamycin or neomycin. However, no significant difference in the population level of Km(R) or Nm(R) soil bacteria was observed between the GM and non-GM corn fields. The nptII gene was not detected in any of the total 3000 Km(R) or Nm(R) isolates screened by PCR. Further, total soil bacterial cells were collected through Nycodenz gradient centrifugation and bacterial community DNA was subjected to PCR. Detection limit was about 500 cells per gram of fresh soil. Our study suggests that the nptII gene was relatively rare in the soil bacterial populations and there was no evidence of gene transfer from a GM corn plant to soil bacteria based on the data from total soil bacterial communities.  相似文献   
884.

Background, aim, and scope  

Ever since the discovery of the mutagenic properties of ionizing radiation, the possibility of birth sex odds shifts in exposed human populations was considered in the scientific community. Positive evidence, however weak, was obtained after the atomic bombing of Japan. We previously investigated trends in the sex odds before and after the Chernobyl Nuclear Power Plant accident. In a pilot study, combined data from the Czech Republic, Denmark, Finland, Germany, Hungary, Norway, Poland, and Sweden between 1982 and 1992 showed a downward trend in the sex odds and a significant jump in 1987, the year immediately after Chernobyl. Moreover, a significant positive association of the sex odds between 1986 and 1991 with Chernobyl fallout at the district level in Germany was observed. Both of these findings, temporality (effect after exposure) and dose response association, yield evidence of causality. The primary aim of this study was to investigate longer time periods (1950–2007) in all of Europe and in the USA with emphasis on the global atmospheric atomic bomb test fallout and on the Chernobyl accident. To obtain further evidence, we also analyze sex odds data near nuclear facilities in Germany and Switzerland.  相似文献   
885.

Background  

Airborne fine particulates (PM 2.5) and its associated polycyclic aromatic hydrocarbons (PAHs) are reportedly hazardous in urban environment due to the presence of multiple emission sources.  相似文献   
886.

Purpose  

We tested the genetic diversity in wild mice (Mus musculus domesticus) inhabiting the asbestos-polluted area as a model for the long-term mutagenic effect of asbestos. Hazardous effects of deposited asbestos persist in the environment because of low rate of fiber disintegration. The upper layers of the soil in the vicinity of a former asbestos factory are nearly “saturated” with asbestos fibers and dust. Natural populations of mice dwell in this area and are constantly exposed to asbestos fibers.  相似文献   
887.

Purpose  

Due to their high water solubilities and mobilities, persistent, polar perfluorinated compounds (PFCs) such as perfluorinated carboxylates and sulfonates are likely to end up in the oceans. In part 1 of this study, their distribution in North and Baltic Sea water is reported, being of special interest because these seas are surrounded by highly industrialized countries with high population densities.  相似文献   
888.
Zuo Y  Zhang K  Wu J  Men B  He M 《Chemosphere》2011,83(7):1014-1019
Phthalic acid and its photochemical degradation has been determined in snow and rainwater samples collected during winters (2003-2010) in the Southeast of Massachusetts using capillary gas chromatography (GC) with flame ionization and mass spectrometric detection. Water samples were dried using a rotary evaporator and derivatized with a 14% BF3/methanol reagent before GC analysis. The developed method proved simple and accurate. Phthalic acid was found in snow samples collected in a concentration range of 7.22-76.5 nM. The photodegradation of phthalate was carried out under 300 nm UV light. The direct photodecomposition of the acid is slow (5% h−1). However, the addition of dissolved Fe(III) species at 2.0 μM accelerated the light-induced degradation of phthalic acid by 3.5 times in the atmospheric water samples. Photodegradation rates of phthalic acid increases with decreasing pH value of water samples in the range of pH 2.8-4.5.  相似文献   
889.
Zhang YF  He LY  Chen ZJ  Wang QY  Qian M  Sheng XF 《Chemosphere》2011,83(1):57-62
One hundred Cu-resistant-endophytic bacteria were isolated from Cu-tolerant plants grown on Cu mine wasteland, of which, eight Cu-resistant and 1-aminocyclopropane-1-carboxylate (ACC) deaminase-producing endophytic bacteria were obtained based on the ACC deaminase activity of the bacteria and characterized with respect to metal resistance, production of ACC deaminase, indole-3-acetic acid (IAA) as well as siderophores and mineral phosphate solubilization. Ralstonia sp. J1-22-2, Pantoea agglomerans Jp3-3, and Pseudomonas thivervalensis Y1-3-9 with higher ACC deaminase activity (ranging from 213 to 370 μM α-ketobutyrate mg(-1)h(-1)) were evaluated for promoting plant growth and Cu uptake of rape grown in quartz sand containing 0, 2.5, and 5 mg kg(-1) of Cu in pot experiments. The eight bacteria were found to exhibit different multiple heavy metal resistance characteristics, to show different levels of ACC deaminase activity and to produce indole acetic acid. Seven bacteria produced siderophores and solubilized inorganic phosphate. Pot experiments showed that inoculation with the strains (J1-22-2, Jp3-3, and Y1-3-9) was found to increase the biomass of rape. Increases in above-ground tissue Cu contents of rape cultivated in 2.5 and 5 mg kg(-1) of Cu-contaminated substrates varied from 9% to 31% and from 3 to 4-fold respectively in inoculated-rape plants compared to the uninoculated control. The maximum Cu uptake of rape was observed after inoculation with P. agglomerans Jp3-3. The results show that metal-resistant and plant growth promoting endophytic bacteria play an important role in plant growth and Cu uptake which may provide a new endophytic bacterial-assisted phytoremediation of Cu-contaminated environment.  相似文献   
890.
微生物浸出印刷线路板中金属的研究进展   总被引:1,自引:0,他引:1  
印刷线路板作为电子产品中不可缺少的部件,具有成分复杂、环境危害大和资源化价值高等特点,对废印刷线路板成分进行科学有效地分离富集一直是电子废弃物资源化利用研究的热点和难点.从适用的微生物种类、微生物的浸提机制、影响微生物浸提效果的因素等方面综述了微生物在印刷线路板中金属的浸出中的应用研究状况,最后对未来的研究方向进行了展...  相似文献   
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