Genotoxic potentials and related mechanisms of bisphenol A and other bisphenol compounds: A comparison study employing chicken DT40 cells

Bisphenol A (BPA) has been found in plastic food containers, paper currencies and toys. BPA has been reported for various adverse health concerns including reproduction, development and carcinogenesis. These potential health implications have led to increasing use of alternative bisphenols such as bisphenol F and bisphenol S among many. However, little is known about the toxicity of alternative bisphenols and most of the toxicological information is limited to endocrine disrupting potentials. In this study, we evaluated cytotoxicity and the genotoxic potentials of several bisphenol compounds, and identified the mechanism of genotoxicity using a panel of mutant chicken DT40 cell lines deficient in DNA repair pathways. Several bisphenols including bisphenol AP, bisphenol M, or bisphenol P exerted genotoxic potentials that are greater than that of BPA. Generally RAD54^−/− mutant cells were the most sensitive to all bisphenols except for bisphenol F, suggesting the induction of DNA double-strand breaks that could be rescued by homologous recombination. Genotoxic potential of bisphenols was confirmed by chromosomal aberration assay and γ-H2AX foci forming assay between wild-type and RAD54^−/− mutant. Among the tested bisphenols, BPP at 12.5 μM showed the greatest genotoxic potency, inducing chromosomal aberration and γ-H2AX foci in RAD54^−/− mutant by 2.6 and 4.8 folds greater than those in wild-type, respectively. Our results clearly show several alternative bisphenols can cause genotoxicity that could be rescued by homologous recombination pathway, and some bisphenols induced even greater genotoxic potentials than that of BPA.     

我国“十一五”火力发电企业关停容量及节能分析与建议

从我国节能减排的政策出发，分析了“十一五”期间我国已关停的小火电机组容量、机组装机范围、企业分布等特征，以及其节能降耗与环保效果。预测了“十一五”关停小火电机组容量，并提出了相关建议。     

Escaping radioactivity from coal-fired power plants (CPPs) due to coal burning and the associated hazards: a review

Coal, like most materials found in nature, contains trace quantities of the naturally occurring primordial radionuclides, i.e. of ⁴⁰K and of ²³⁸U, ²³²Th and their decay products. Therefore, the combustion of coal results in the released into the environment of some natural radioactivity (1.48 TBq y⁻¹), the major part of which (99 %) escapes as very fine particles, while the rest in fly ash. The activity concentrations of natural radionuclides measured in coals originated from coal mines in Greece varied from 117 to 435 Bq kg⁻¹ for ²³⁸U, from 44 to 255 Bq kg⁻¹ for ²²⁶Ra, from 59 to 205 Bq kg⁻¹ for ²¹⁰Pb, from 9 to 41 Bq kg⁻¹ for ²²⁸Ra (²³²Th) and from 59 to 227 Bq kg⁻¹ for ⁴⁰K. Fly ash escapes from the stacks of coal-fired power plants in a percentage of 3-1% of the total fly ash, in the better case. The natural radionuclide concentrations measured in fly ash produced and retained or escaped from coal-fired power plants in Greece varied from 263 to 950 Bq kg⁻¹ for ²³⁸U, from 142 to 605 Bq kg⁻¹ for ²²⁶Ra, from 133 to 428 Bq kg⁻¹ for ²¹⁰Pb, from 27 to 68 Bq kg⁻¹ for ²²⁸Ra (²³²Th) and from 204 to 382 Bq kg⁻¹ for ⁴⁰K. About 5% of the total ash produced in the coal-fired power plants is used as substitute of cement in concrete for the construction of dwellings, and may affect indoor radiation doses from external irradiation and the inhalation of radon decay products (internal irradiation) is the most significant. The resulting normalized collective effective doses were 6 and 0.5 man-Sv (GW a)⁻¹ for typical old and modern coal-fired power plants, respectively.     

南京市不同时间尺度温度变化特征

利用南京市1951～2005年的气温资料，研究了南京市不同时间尺度的气温变化特征。结果表明：1951～2005年，南京市温度的年变化呈现上升趋势，年平均最高温度的上升幅度较年平均最低温度高，温度日较差（DTR）的年平均值为下降趋势，1992年可作为近55a南京地区冷暖期的转折点。温度的季节变化也多数呈现上升趋势，四季的平均气温增暖幅度最大是春季，最小的是夏季；四季的平均最高气温与平均最低气温多数都表现为上升的趋势，只有夏季的平均最高温度表现为下降的趋势。因此，近55a南京市在温度总体呈现上升趋势的情况下，夏季有变凉的趋势。四季的DTR的变化中，只有春季为上升趋势，其余季节都是下降的趋势。极端年份的日平均温度变化趋势基本一致，但各年份的DTR变化趋势却不相同。     

离子选择电极法测定水中40K的影响因素

对离子选择电极法测定水中^40K的影响因素进行了探讨,确定了用此方法测定水溶液中^40K的最佳实验条件,在此实验条件下,所得结果最接近标准值。     

Fuelwood assessment at micro-watershed level in Northeast Himalaya: a case study in Manipur,India

Fuelwood is one of the major sources of energy in the domestic sector across the rural areas, especially in the developing regions across the world. The Northeastern Himalayan state of Manipur is dominated by the tribal population that largely depends on fuelwood from the nearby forest area. The entire dependence on forests for energy resources is affecting the sustainability of the forest ecosystem in the region, thus indicating the livelihood conditions. Since land-use land-cover change is the key driver to the change in resource availability of a region, the present study has tried to analyze the land-cover changes over a period 28 years. The second major component affecting resource availability is the increasing population pressure that leads to changes in the land dynamics, which directly affect the resource production. Based on the existing consumption pattern, the total consumption of fuelwood in the watershed ranges from a minimum of 289.992 tons/year to a maximum of 3545.719 tons/year with an average of 1561.956 tons/year in the year 2009 and simulated fuelwood consumption for the year 2021 is around 1469.260 tons/year. Nine different probable scenarios of resource are proposed to calculate the stress value that can be used by the policy-makers and planners for suitable policy implementation at the micro level with a complex social system.     

H_4SiW_(12)O_(40)/TiO_2/beads光催化降解亚甲基蓝的研究

以钛酸四丁酯为原料,空心微珠为载体,采用溶胶-凝胶法制备TiO2/beads光催化剂载体,然后浸渍法制备出H4SiW12O40/TiO2/beads表面负载修饰型复合光催化剂,并运用SEM、XRD、FT-IR和DRS对催化剂进行表征和分析.研究了H4SiW12O40/TiO2/beads对亚甲基蓝降解的光催化活性,考察了光强度、pH值、曝气量、底物浓度和催化剂用量等对催化效率的影响.实验结果表明,在中性条件下,H4SiW12O40/TiO2/beads催化剂的投加量为0.25 g/L,浓度为7.5 mg/L的亚甲基蓝溶液在250 W的紫外灯和600 W的可见光灯下光照60 min降解率分别可达到94.5%和55%.     

H4SiW12O40/TiO2/beads光催化降解亚甲基蓝的研究

以钛酸四丁酯为原料，空心微珠为载体，采用溶胶凝胶法制备TiO₂/beads光催化剂载体，然后浸渍法制备出H₄SiW₁₂O₄₀/TiO₂/beads表面负载修饰型复合光催化剂，并运用SEM、XRD、FT-IR和DRS对催化剂进行表征和分析。研究了H₄SiW₁₂O₄₀/TiO₂/beads对亚甲基蓝降解的光催化活性，考察了光强度、pH值、曝气量、底物浓度和催化剂用量等对催化效率的影响。实验结果表明，在中性条件下，H₄SiW₁₂O₄₀/TiO₂/beads催化剂的投加量为0.25 g/L，浓度为7.5 mg/L的亚甲基蓝溶液在250 W的紫外灯和600 W的可见光灯下光照60 min降解率分别可达到94.5%和55%。     

Damos: Twenty Years of Dredged Material Disposal Site Monitoring. Isn'st That Enough?

Since 1977, the US Army Corps of Engineers Disposal Area Monitoring System (DAMOS) has monitored New England's offshore dredged material disposal sites. DAMOS has shown that by using monitoring information to make management decisions, open water disposal of dredged sediments is possible with minimal environmental impact. Over the past two decades, DAMOS has answered many of the key questions about dredged material impacts. Yet the need for such a programme remains strong from both the technical and public interest perspectives. the programme continues to monitor projects that are extending our knowledge in the areas of deeper water capping, geotechnical behaviour of capping and capped materials, and biological response to contaminants. These investigations, along with the need for specific disposal site surveys, will continue to provide valuable technical information needed by the public, policy makers, and regulators to make critical decisions on dredged sediment management.     

Determination of Cs in the water system of a pre-Alpine lake

The aim of this study was to measure the ¹³⁷Cs activity derived from the Chernobyl accident in the water system of Lake Wallersee, a pre-Alpine lake in Austria within an area highly contaminated by the Chernobyl fallout.