Bioenhancement of cadmium transfer along a multi-level food chain

Previous studies have shown that metal partitioned to a subcellular compartment containing trophically available metal (TAM) is readily available to predators and may be enhanced by increased binding of metal to heat-stable proteins (HSP - e.g., metallothioneins). The aim of the current investigation was to determine the influence of TAM on the trophic transfer of Cd along an experimental, three-level food chain: Artemia franciscana (brine shrimp)-->Palaemonetes pugio (grass shrimp)-->Fundulus heteroclitus (mummichog). P. pugio were fed for 7 days on A. franciscana exposed to Cd in solution (including (109)Cd as radiotracer) and subjected to subcellular fractionation or fed to F. heteroclitus. An HSP-driven increase in the percentage of Cd associated with TAM (TAM-Cd%) in A. franciscana exposed to 1 muM Cd resulted in a bioenhancement (i.e., a greater than linear increase with respect to A. franciscana exposure) of Cd trophic transfer to P. pugio. Increased dietary Cd exposure did not affect TAM-Cd% in P. pugio nor trophic transfer to F. heteroclitus.     

世界上最丰富的化石宝库幸得保护--美国科学家在撰文报道此事

美国国家科学基金会的海洋地质学家比拉·哈克博士 (ＢｉｌａｌＨａｑ) ,是在我国改革开放初期第一位访问中国科学院海洋研究所的高级访问学者 (１９７９年 )。访问期间作了关于“深海钻探”(ＤＳＤＰ)———海洋地质领域最新动态的学术报告 ,并赠送了书 ,对我国海洋地质学研究的开展起了重要推动作用。此后 ,哈克博士多次访问北京、上海、杭州、青岛 ,讲授海洋地质学方面的最新国际动态和发展方向。特别值得提出的是１９９９年１０月哈克来山东青岛参加“亚洲海洋地质学术研讨会”期间 ,参观、考察了“山旺化石保护区” ,对保护区的现状十…     

欧亚冰盖的消融

巴巴多斯和新几内亚的海平面变化表明：在过去的15000a中曾有过两次大规模的冰川融水流．同其它环境变化(如北大西洋深水环流)相比，这两次融水流形成的时间显然有助于我们进一步了解从未次冰期到问冰期的气候变迁及新仙女木事件．     

著名海洋地质学家秦蕴珊研究员

秦蕴珊，男，山东掖县人，1933年6月生，1956年毕业于北京地质学院。秦蕴珊研究员是我国著名的海洋地质学家。现任中国科学院海洋研究所所长，中国海洋湖沼学会理事长，中国海洋研究委员会主席。《海洋与湖沼》学报主编。他为我国海洋地质学科的创立和发展做出了重要贡献。他对中国陆架沉积作用和海底沉积物的类型、分布及物质组成进行了大量的调查和深入研究，不但从宏观上阐明了沉积物分布的空间格局，而且划分出两种不同时代和不同成因的内陆架和外陆架沉积，并编绘了完整的中国海陆架沉积类型图，建立了中国陆架的海底沉积模式。被国内…     

Impact-generated atmospheres over Titan, Ganymede, and Callisto

The competition between impact erosion and impact supply of volatiles to planetary atmospheres can determine whether a planet or satellite accumulates an atmosphere. In the absence of other processes (e.g., outgassing), we find either that a planetary atmosphere should be thick, or that there should be no atmosphere at all. The boundary between the two extreme cases is set by the mass and velocity distributions and intrinsic volatile content of the impactors. We apply our model specifically to Titan, Callisto, and Ganymede. The impacting population is identified with comets, either in the form of stray Uranus-Neptune planetesimals or as dislodged Kuiper belt comets. Systematically lower impact velocities on Titan allow it to retain a thick atmosphere, while Callisto and Ganymede get nothing. Titan's atmosphere may therefore be an expression of a late-accreting, volatile-rich veneer. An impact origin for Titan's atmosphere naturally accounts for the high D/H ratio it shares with Earth, the carbonaceous meteorites, and Halley. It also accounts for the general similarity of Titan's atmosphere to those of Triton and Pluto, which is otherwise puzzling in view of the radically different histories and bulk compositions of these objects.     

第五届全国油气储层学术研讨会在成都举行

第五届全国油气储层学术研讨会于2008年8月28～31日在四川省成都市召开。会议由中国地质学会沉积地质专业委员会、中国矿物岩石地球化学学会沉积学专业委员会主办,成都理工大学承办,中石油西南油气田分公司、中石化西南油气分公司、勘探南方分公司等单位协办。     

磷处理粉煤灰可作农业土壤磷源

粉煤灰(简称CCP或ash)具有改良土壤,增加植物产量的功能。此外,由于它特殊的多孔结构,也可用作吸纳并承载植物养分的载体。用NaH2PO4配制成含磷0.10mol/L浓度的溶液,对采自加拿大西安大略省Sarnia地区Lambton电厂的底灰(bottomash)进行振荡浸渍处理。结果表明,振荡浸渍66h后的粉煤灰中磷含量可达784×10-6。以磷处理粉煤灰、未进行磷处理的粉煤灰和石英砂按比例混合,作为基本生长介质进行玉米种植实验,其中实验配方设计为生长介质中含磷量分别为标准含磷浓度(50×10-6)的10%、25%、50%、75%和100%。生长26、34和46d后分别与不含磷的空白配方、施加含氮-磷-钾为0-20-0标准磷肥并控制磷含量为标准浓度(50×10-6)配方进行生物产量对比。生长实验结果表明,以磷处理粉煤灰供磷的生长介质,当含磷量为标准浓度的25%至100%时,其植物生长量就比添加标准浓度磷肥的配方好。种植46d后的生物生长量统计结果显示,含磷分别为标准浓度50%、75%和100%的实验介质中,玉米杆的鲜重较施标准磷肥介质中玉米分别增长39.46%、42.73%和46.13%;玉米杆干重依次增加29.71%、13.39%和28.87%;根鲜重平均增加16.62%;根干重平均增加14.03%。上述实验结果启示,粉煤灰可以很好地吸纳承载磷养分,并持续供给植物吸收生长,如果采用吸纳磷(或其他养分)的粉煤灰改良砂质土壤将有重要意义。     

The spatial mobility of two generations of young adults in Norway

"This article presents results from a longitudinal study using data from the Norwegian population register, combined with data from the 1970 and 1980 censuses. For two generations, those born in 1948 and 1958, successive migrations are considered and the effects of various sociodemographic characteristics on migratory behaviour are explored....Event-history analysis is used to examine the duration of stay at the place reached at age 22, and the effects of individual characteristics on this duration. Since a distinction is made between intra- and inter-regional migration, it has been possible to show that these effects vary significantly depending on whether we are dealing with short- or long-distance migration."