Biomedical subjects

Shu Tao

Publications and source records attributed to Shu Tao.

59 records · Page 4Linked to original sources

PubMed2002

History, development and characteristics of lake ecological models.

This paper provides some introductory information on the history, development, and characteristics of various lake ecosystem models. The modeling of lake ecological processes began to gain importance in the early 1960s. There are a number of models available today, with varying levels of complexity to cope with the variety of environmental problems found in lake environments, e.g. eutrophication, acidification, oxygen depletion, wetland management, heavy metal and pesticide pollution, as well as hydrodynamic problems. In particular, this paper focuses on lake eutrophication and wetland models, as well as addressing strategies appropriate for the design and development of reliable lake ecological models.

Acid Rain↗

PubMed2002

[Desorption of kaolin adsorbed copper in the fish gill microenvironment].

In order to investigate the bioavailability of kaolin adsorbed copper on gills of carpio, and to explain its possible mechanism in terms of speciation, exposure experiments with constant concentration of water soluble copper and increased concentration of kaolin adsorbed copper was carried on, and the speciation analyses was developed using MINTEQA2. The results of the exposure experiment indicated that expose to kaolin adsorbed copper would increase the metal accumulation in the fish gills. The shift of the copper speciation was demonstrated via chemical equilibrium calculation. To be specific, the kaolin adsorbed copper would be partially desorbed in the fish gill microenvironment in the alkaline water environment.

Adsorption↗

PubMed2002

[Uptake and distribution of Cu, Zn, Pb and Cd in maize related to metals speciation change in rhizosphere].

The behavior of heavy metals in terrestrial system and the mechanism of VAM plant in toleranting excessive heavy metals in soil were examined with VAM maize(Zea mays L.). After seven-week cultivation in sewage-sludging soil, the biomass of VAM (Glomus mosseae) maize was found 1.5 times higher than non-mycorrhizal one. Compared with non-mycorrhizal maize, the accumulation of Cu, Zn and Pb by mycorrhizal maize was reduced by 10%, 18% and 29%, respectively, but the accumulation of Cd was the same. The distribution and speciation change of Cu, Zn, Pb and Cd in rhizosphere of VAM and non-mycorrhizal maize were analyzed by using the technique of sequential extraction. Except a significant increase in exchangeable Cu in rhizosphere of VAM maize, the increased amount of test metals bound to organic matter, carbonates, iron and manganese oxides were significantly higher than those in rhizosphere of non-mycorrhizal maize, indicating that the speciation of metals in rhizosphere of mycorrhizal maize growing in contaminated soil tended to be relatively stable. Meanwhile, the influence of metal speciation in rhizosphere on its bioavailability as well as the mechanism of mycorrhizal plant in toleranting excess metals were also discussed.

Cadmium↗

PubMed2002

[Extraction of organochlorine pesticides using ASE from wastewater irrigated agricultural soil].

The extraction efficiency of accelerated solvent extraction (ASE) was studied for organochlorine pesticide residuals in soil and compared with that of Soxhlet. The results showed that the efficiency of ASE was generally better than Soxhlet when used for DDT measurement, and equivalent to Soxhlet for BHCs. With ASE, organochlorine pesticide residues were detected in wastewater irrigated and non-wastewater irrigated soils from Tianjin. alpha-BHC, beta-BHC, delta-BHC, gamma-BHC, p,p'-DDE, p,p'-DDD, p,p'-DDT, o,p'-DDT ranged from 7.5 to 71.1 ng/g in wastewater irrigated vegetable and maize field and from 3.0 to 16.5 ng/g in wastewater irrigated paddy field. The eight pesticide residues from non-wastewater irrigated vegetable and maize field was in a range of 3.1-17.6 ng/g.

Agriculture↗

PubMedDate not supplied

Prediction of the bioconcentration factor of PCBs in fish using the molecular connectivity index and fragment constant models.

Models based on molecular connectivity index (MCI) and fragment constant (FC) method were developed for prediction of the bioconcentration factor (BCF) for polychlorobiphenyls (PCBs) in fish. The mean residuals for the MCI and FC models were 0.195 and 0.223 log units, respectively. The two models were then compared in terms of their mean residuals. In addition to the chlorine atom substitution number, other important structural features exhibiting a significant influence on the BCFs of PCB congeners were discussed and incorporated to the models. These features include the degree of the ortho-substitution, the presence of chlorine pairs in the three- and five- positions, and the crowding of chlorine atoms on the phenyl ring.

Animals↗