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1.
Bourdineaud JP Fujimura M Laclau M Sawada M Yasutake A 《Environment international》2011,37(2):303-313
Methylmercury (MeHg) is a potent neurotoxin, and human beings are mainly exposed to this pollutant through fish consumption. Only a few contradictory epidemiological studies are currently available examining the impact of fish consumption on human populations. In the present study, we wanted to address whether a diet mimicking the fish consumption of Western populations could result in observable adverse effects in mice, and whether beneficial nutriments from fish were able to counterbalance the deleterious effects of MeHg, if any. In Europe and the United States, fish consumption varies widely between countries, from 11 to 100 g fish/day. A mid-range value of 25 g fish/day corresponds to a fish contribution to the total diet of 1.25% on a dry weight basis. We decided to supplement a vegetarian-based mouse diet with 1.25% of lyophilized salmon flesh (SAL diet), or 1.25% of a blend of lyophilized cod, tuna, and swordfish (CTS diet). Total mercury contents were 1.15±0.15, 2.3±0.1 and 35.75±0.15 ng Hg/g of food pellets for the control, SAL and CTS diets, respectively. After two months feeding, the CTS diet resulted in significant observable effects as compared to the control and SAL diets, encompassing decreased body growth, altered behavioral performance and increased anxiety level, modification of mitochondrial respiratory protein subunit concentrations in kidney and brain structures, modified gene expression patterns in kidneys, liver and muscles, and a decrease of dopamine concentrations in the hypothalamus and striatum. Our findings have health implications, firstly because 1.25% of CTS flesh in the diet corresponds to an average exposure to MeHg below the WHO provisory tolerable weekly intake (PTWI) (1.6 μg MeHg/kg of body weight/week), and secondly because many people in Western populations, among them women of child-bearing age, are exceeding the PTWI value (for instance, 35% of the French population inhabiting the Atlantic and Mediterranean coasts). 相似文献
2.
Masahiro?ShimadaEmail author Takahiko?Iida Kensuke?Kawarada Yoshifumi?Chiba Toshihiro?Mamoto Takayuki?Okayama 《Journal of Material Cycles and Waste Management》2004,6(2):111-118
We have previously manufactured activated carbon using waste paper board, which was prepared by adding 8% phenol resin adhesive to torn waste newspaper and hot-pressing. In this study, the pretreatment process of the raw material was simplified; the waste paper was extruded to form granules. The activated carbon was manufactured by the carbon dioxide activation method using the granules as the raw material. The properties of the activated carbon were evaluated based on the pore structure, the iodine adsorption number, and the adsorption of toluene vapor in a sealed chamber. The activated carbon, which was manufactured at an activation temperature of 1100°C and a treatment time of 60min, exhibited a specific surface area of 1241m2/g and an iodine adsorption number of 1120mg/g. These results were similar to those obtained for two commercially available activated carbons. The extent of toluene vapor adsorption by this activated carbon was similar to that observed for the two commercial activated carbons over a period of 130min. 相似文献
3.
An improved method for the determination of chlorine in air is described. The principle of this method is based on the absorption of chlorine in p-toluenesulfonamide aqueous solution, followed by color development with a pyridine-pyrazolone reagent. Both the chlorine absorbed in the solution and the color developed with the reagent were stable. Positive interference by nitrogen dioxide was not observed. 相似文献
4.
Reductive dechlorination of non-ortho substituted polychlorinated biphenyls by ultraviolet irradiation in alkaline 2-propanol 总被引:3,自引:0,他引:3
Yuan Yao Kohji Kakimoto Hiroaki I. Ogawa Yasuhiko Kato Yoshifumi Hanada Ryota Shinohara Eiichi Yoshino 《Chemosphere》1997,35(12):2891-2897
The photodechlorination pathways of 3,3′,4,5,5′-pentachlorobiphenyl (3,3′,4,5,5′-PentaCB) and the related lower polychlorinated biphenyl congeners irradiated at 254 nm in alkaline 2-propanol were elucidated. Steric effect is the most important factor for controlling the dechlorination pattern of these substrates. Electronic effect also influences the photoreactivity of chlorine substituents. 相似文献
5.
Núria Roura-Pascual Andrew V Suarez Kristina McNyset Crisanto Gómez Pere Pons Yoshifumi Touyama Alexander L Wild Ferran Gascon A Townsend Peterson 《Ecological applications》2006,16(5):1832-1841
Modeling ecological niches of species is a promising approach for predicting the geographic potential of invasive species in new environments. Argentine ants (Linepithema humile) rank among the most successful invasive species: native to South America, they have invaded broad areas worldwide. Despite their widespread success, little is known about what makes an area susceptible--or not--to invasion. Here, we use a genetic algorithm approach to ecological niche modeling based on high-resolution remote-sensing data to examine the roles of niche similarity and difference in predicting invasions by this species. Our comparisons support a picture of general conservatism of the species' ecological characteristics, in spite of distinct geographic and community contexts. 相似文献
6.
The Science of Nature - 相似文献
7.
文本预处理是文本挖掘的关键一步,建立与信息相匹配的标准语义集合能缩短信息处理的时间,提高信息的提取率和识别精度。根据国家交通事故信息采集规范要求,从国家公共安全行业标准中抽取相关交通事故基本信息的标准词汇及代码,构建了一套含有12个属性项目、185个标准词汇的交通事故信息文本预处理用标准化语义集合,并将其应用于国家安全生产监督管理总局的事故查询系统,对系统中2004—2014年期间所收集的8 156件重大道路交通事故信息中的文本数据进行分析。结果表明:利用这套语义集合能更多地提取交通事故信息,可为准确捕捉交通事故特征和研究交通事故发生机理提供重要依据,也为开发交通事故自动信息识别系统创造了重要的条件。 相似文献
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The biodegradabilities of two polyester, P(3HB-co-3HV) and PCL, in soil were studied to examine the factors affecting the biodegradability of biodegradable plastics in soil. The polymers were mixed with soil and the time course of the biodegradation of the polymer was measured by analyzing the residual polymer. The polymer biodegraded little in early period of the test, but did in the first-order kinetics after a certain time which was dependent on the test substance and soil used. The rate constant and the induction period of the biodegradation were determined from the residual curve. The rate constant and the induction period for P(3HB-co-3HV) increased and reached to the constant values with increasing the particle size of the test substance. Both values depended on the kind of test soil and on the sampling date for the same kind of soil. The variation in the biodegradability among the same kind of soil was primarily attributed to the variation in water content of the soil. The rate constant and the induction period of PCL were smaller and longer than P(3HB-co-3HV), respectively. 相似文献
10.
Fuminori Ito Yoshifumi Touyama Ayako Gotoh Shungo Kitahiro Johan Billen 《Die Naturwissenschaften》2010,97(8):725-728
Thelytokous parthenogenesis in which diploid females are produced from unfertilized eggs, was recently reported for some ant
species. Here, we document thelytokous reproduction by queens in the polygynous species Pyramica membranifera. Queens that emerged in the laboratory were kept with or without workers under laboratory conditions. Independent colony
founding was successful for a few queens if prey was provided. All artificial colonies, which started with a newly emerged
queen and workers produced new workers and some of the colonies also produced female sexuals. Some of the female sexuals shed
their wings in the laboratory and started formation of new polygynous colonies. Workers had no ovaries and thus, were obligatorily
sterile. 相似文献