45 research outputs found

    Chemical Fractionation Of Cu And Zn And Their Impacts On Microbial Properties In Slightly Contaminated Soils

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    Chemical fractionation of Cu and Zn in bulk soil and its effects on soil microbial properties were determined in Cu and Zn contaminated soils (Cu: 35.57~46.37 mg·kg-1, Zn: 74.33~127.20 mg·kg-1) sampled from an agricultural field in outskirts of Zibo, China during the month of September, 2011. A sequential extraction technique (SET) was used for metals chemical fractionation analysis in soils and a correlation analysis was applied to determinate the effects of metal on soil microbial properties. Chemical speciation showed that Cu and Zn were mostly present in the residual fraction and their concentrations in the most labile fraction (acid soluble fraction) were the lowest in the investigated soils. However, the correlation analysis indicated that the labile forms of Cu/Zn, such as its acid soluble, reducible or oxidizable fractions, were usually significantly negatively correlated with the tested microbial activities at 0.05 or 0.01 probability levels. These results indicate that the metal labile fractions could exert an inhibitory effect on the soil microbial parameters even in the minor contaminated soils. Int. J. Agril. Res. Innov. & Tech. 3 (1): 20-25, June, 2013 DOI: http://dx.doi.org/10.3329/ijarit.v3i1.1604

    Lake area changes and their influence on factors in arid and semi-arid regions along the Silk Road

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    In the context of global warming, the changes in major lakes and their responses to the influence factors in arid and semi-arid regions along the Silk Road are especially important for the sustainable development of local water resources. In this study, the areas of 24 lakes were extracted using MODIS NDVI data, and their spatial-temporal characteristics were analyzed. In addition, the relationship between lake areas and the influence factors, including air temperature, precipitation, evapotranspiration, land use and land cover change (LULCC) and population density in the watersheds, were investigated. The results indicated that the areas of most lakes shrank, and the total area decreased by 22,189.7 km2 from 2001 to 2016, except for those of the lakes located on the Qinghai-Tibetan Plateau. The air temperature was the most important factor for all the lakes and increased at a rate of 0.113 °C/a during the past 16 years. LULCC and the increasing population density markedly influenced the lakes located in the middle to western parts of this study area. Therefore, our results connecting lake area changes in the study region highlight the great challenge of water resources and the urgency of implementation of the green policy in the One Belt and One Road Initiative through international collaboration

    Adaptation response of Pseudomonas fragi on refrigerated solid matrix to a moderate electric field

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    We have conducted a Raman study of methane (CH4), a major constituent of the outer planets, at pressures up to 165 GPa. We observe splitting of the principal Raman-active vibrational mode above 45 GPa and a nonlinear dependence of Raman peak position on pressure. A discontinuous change in the pressure derivative of the ν3 peak position is observed at approximately 75 GPa, corresponding to the phase change previously observed using X-ray diffraction. The Grüneisen parameters for the principal Raman-active modes of methane in the simple cubic and high-pressure cubic phases are calculated. The predicted dissociation of methane at ultrahigh pressure to form C2H6 and H2 is not observed, but an additional discontinuous change in the pressure-induced shift of the Raman peaks is observed at 110 GPa. We suggest that this may be due to some reorientation or reordering of the methane molecules within the framework of the known cubic lattice

    Hepatic senescence, the good and the bad

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    Gradual alterations of cell's physiology and functions due to age or exposure to various stresses lead to the conversion of normal cells to senescent cells. Once becoming senescent, the cell stops dividing permanently but remains metabolically active. Cellular senescence does not have a single marker but is characterized mainly by a combination of multiple markers, such as, morphological changes, expression of cell cycle inhibitors, senescence associated β-galactosidase activity, and changes in nuclear membrane. When cells in an organ become senescent, the entire organism can be affected. This may occur through the senescence-associated secretory phenotype (SASP). SASP may exert beneficial or harmful effects on the microenvironment of tissues. Research on senescence has become a very exciting field in cell biology since the link between age-related diseases, including cancer, and senescence has been established. The loss of regenerative and homeostatic capacity of the liver over the age is somehow connected to cellular senescence. The major contributors of senescence properties in the liver are hepatocytes and cholangiocytes. Senescent cells in the liver have been implicated in the etiology of chronic liver diseases including cirrhosis and hepatocellular carcinoma and in the interference of liver regeneration. This review summarizes recently reported findings in the understanding of the molecular mechanisms of senescence and its relationship with liver diseases
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