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[en] The leaves of Actinidia chinensis in vitro were used as explants in tissue culture to induce calli. The calli were cultured in MS medium containing NaCl for eight passages. The concentration of NaCl in the medium was increased step by step. 60Coγ -rays were used as mutagens. The experiment for selecting medium was designed with orthogonal method. The cell lines tolerated to 0.5, 0.7, 1.0% NaCl were established separately. The regenerated plants from various NaCl tolerant cell lines were obtained. The results are as follows: 1. MS + 0.5 ppm 2,4 - D + 1.0 ppm Zt was the best medium for inducing callus, MS + 0.2 ppm IBA + 1.0 ppm Zt was the best for differentiation and MS + 0.5 ppm IBA was the best for rooting. 2. Growing of the callus was inhibited by NaCl. The growth of callus decreased significantly in 0.3% NaCl, and decreased very significantly in 0.5% NaCl. Therefore, 05% NaCl concentration can be considered as the critical value for salt-tolerance selection. 3. γ-rays over 5kR not only caused incresed of cell size but also inhibited growth of the callus. So, 5kR γ-rays can be considered as optimum mutation dose
[en] Uranium-bearing mine water of Fuzhou Jin'an Uranium Co., Ltd was treated by using poly-aluminum chloride (PAC). The experimental results showed when the pH was 7 and the addition amount of PAC was 40 mg/L, the removal rate of suspended solid was more than 91%, and the sedimentation rate was less then 25%. (authors)
[en] Under the conditions of mixed acid medium (sulfuric acid and phosphoric acid) and excess potassium iodide, manganese dioxide in pyrolusite reacted with potassium iodide, quantitative iodine was precipitated, and the precipitated iodine was titrated with the standard solution of sodium thiosulfate. The measured results were consistent with the standard value, and the relative standard deviation was less than 0.11%. This method is simple, rapid, accurate and reliable, with satisfactory results, suitable for the analysis of production process. (authors)
[en] The results of present study indicated that laminas, especially first and second lamina from top, were the most important assimilating organs of large-spike cultivar of wheat at flag leaf stage. More than ninety percent of assimilate of a single stem was made by laminas, while the assimilate amount of sheathes only accounted for less than 10%. Not only assimilating rate but also transport and distribution efficiency was declined when the density was too high. Deferring top-dressing time of nitrogen fertilizer could increase both assimilate amount and transport and distribution efficiency
[en] High rate (> 50 μm/h) growth of homoepitaxial single-crystal diamond (SCD) is carried out by microwave plasma chemical vapour deposition (MPCVD) with added nitrogen in the reactant gases of methane and hydrogen, using a polycrystalline-CVD-diamond-film-made seed holder. Photoluminescence results indicate that the nitrogen concentration is spatially inhomogeneous in a large scale, either on the top surface or in the bulk of those as-grown SCDs. The presence of N-distribution is attributed to the facts: (i) a difference in N-incorporation efficiency and (ii) N-diffusion, resulting from the local growth temperatures changed during the high-rate deposition process. In addition, the formed nitrogen-vacancy centres play a crucial role in N-diffusion through the growing crystal. Based on the N-distribution observed in the as-grown crystals, we propose a simple method to distinguish natural diamonds and man-made CVD SCDs. Finally, the disappearance of void defect on the top surface of SCDs is discussed to be related to a filling-in mechanism. (condensed matter: structure, mechanical and thermal properties)
[en] Fibronectin (FN) is known to be a large multifunction glycoprotein with binding sites for many substances, including N-terminal and C-terminal heparin-binding domains. We investigated the effects of highly purified rhFNHN29 and rhFNHC36 polypeptides originally cloned from the two heparin-binding domains on the adhesion and invasion of highly metastatic human hepatocellular carcinoma cells (MHCC97H) and analyzed the underlying mechanism involved. The MHCC97H cells that adhered to FN in the presence of various concentrations of rhFNHN29 and rhFNHC36 polypeptides were stained with crystal violet and measured, and the effects of rhFNHN29 and rhFNHC36 on the invasion of the MHCC97H cells were then detected using the Matrigel invasion assay as well as a lung-metastasis mouse model. The expression level of integrins and focal adhesion kinase (FAK) phosphotyrosyl protein was examined by Western blot, and the activity of matrix metalloproteinases (MMPs) and activator protein 1 (AP-1) was analyzed by gelatin zymography and the electrophoretic mobility band-shift assay (EMSA), respectively. Both of the polypeptides rhFNHN29 and rhFNHC36 inhibited adhesion and invasion of MHCC97H cells; however, rhFNHC36 exhibited inhibition at a lower dose than rhFNHN29. These inhibitory effects were mediated by integrin αvβ3 and reversed by a protein tyrosine phosphatase inhibitor. Polypeptides rhFNHN29 and rhFNHC36 abrogated the tyrosine phosphorylation of focal adhesion kinase (p-FAK) and activation of activator protein 1 (AP-1), resulting in the decrease of integrin αv, β3 and β1 expression as well as the reduction of MMP-9 activity. Polypeptides rhFNHN29 and rhFNHC36 could potentially be applicable to human liver cancer as anti-adhesive and anti-invasive agents
[en] Although organic compounds in marine atmospheric aerosols have significant effects on climate and marine ecosystems, they have rarely been studied, especially in the coastal regions of East China. To assess the origins of the organic aerosols in the East China coastal atmosphere, PM2.5 samples were collected from the atmospheres of the Yellow Sea, the East China Sea, and Changdao Island during the CAPTAIN (Campaign of Air PolluTion At INshore Areas of Eastern China) field campaign in the spring of 2011. The marine atmospheric aerosol samples that were collected were grouped based on the backward trajectories of their air masses. The organic carbon concentrations in the PM2.5 samples from the marine and Changdao Island atmospheres were 5.5 ± 3.1 μgC/m3 and 6.9 ± 2.4 μgC/m3, respectively, which is higher than in other coastal water atmospheres. The concentration of polycyclic aromatic hydrocarbons (PAHs) in the marine atmospheric PM2.5 samples was 17.0 ± 20.2 ng/m3, indicating significant continental anthropogenic influences. The influences of fossil fuels and biomass burning on the composition of organic aerosols in the coastal atmosphere of East China were found to be highly dependent on the origins of the air masses. Diesel combustion had a strong impact on air masses from the Yangtze River Delta (YRD), and gasoline emissions had a more significant impact on the “North China” marine atmospheric samples. The “Northeast China” marine atmospheric samples were most impacted by biomass burning. Coal combustion contributed significantly to the compositions of all of the atmospheric samples. The proportions of secondary compounds increased as samples aged in the marine atmosphere indicating that photochemical oxidation occured during transport. Our results quantified ecosystem effects on marine atmospheric aerosols and highlighted the uncertainties that arise when modeling marine atmospheric PM2.5 without considering high spatial resolution source data and meteorological parameters. - Highlights: • Molecular and spatial characteristics of particulate organic compounds in coastal atmosphere of East China are reported. • Terrestrial fossil fuels and biomass burning have significant influences on aerosols in coastal atmosphere of East China. • Continental influences are highly dependent on the air mass origins. • Proportion of compounds from photochemical oxidation increased during the long range transport. - Capsule: Influences of continental anthropogenic sources on the composition of organic aerosols in the coastal atmosphere of East China were found to be significant and dependent on the origins of the air masses.
[en] Bauxite residue often has poor physical conditions which impede plant growth. Native plant encroachment on a bauxite residue disposal area in Central China reveals that natural regeneration may improve its physicochemical properties. Residue samples collected from three different disposal ages were assessed to evaluate residue micromorphology and three-dimensional (3D) aggregate microstructure under natural regeneration. The residue aggregates in different disposal ages were divided in two sections: macro-aggregate (2–1 mm) and micro-aggregate (0.25–0.05 mm). Residue aggregate micromorphology was determined by scanning electron microscope and energy dispersive X-ray spectroscopy, and the residue aggregate microstructure was determined by synchrotron-based X-ray micro-computed tomography (SR-μCT) and image analysis techniques. Natural regeneration may improve residue aggregate stability and form a stable aggregate structure. Calcium content increased whilst sodium content decreased significantly on the surface of residue aggregates. Under natural soil-forming processes bauxite residue porosity, specific surface area, average length of paths, and average tortuosity of paths all significantly increased. This demonstrated that natural regeneration may stimulate the formation of stable aggregate structure in residues. Further understanding should focus on particle interaction forces and agglomeration mechanisms with the addition of external ameliorations. - Highlights: • Weathering improved physico-chemical properties of bauxite residue and changed micromorgrophy of residue aggregates. • Weathering stimulated the formation of stable aggregate structures in residues. • Weathering changed aggregate microstructures, including pore throat and shape parameters.
[en] Rice is one of the major pathways of arsenic (As) exposure in human food chain, threatening over half of the global population. Greenhouse pot experiments were conducted to examine the effects of Si application on iron (Fe) plaque formation, As uptake and rice grain As speciation in indica and hybrid rice genotypes with different radial oxygen loss (ROL) ability. The results demonstrated that Si significantly increased root and grain biomass. Indica genotypes with higher ROL induced greater Fe plaque formation, compared to hybrid genotypes and sequestered more As in Fe plaque. Silicon applications significantly increased Fe concentrations in iron plaque of different genotypes, but it decreased As concentrations in the roots, straws and husks by 28–35%, 15–35% and 32–57% respectively. In addition, it significantly reduced DMA accumulation in rice grains but not inorganic As accumulation. Rice of indica genotypes with higher ROL accumulated lower concentrations of inorganic As in grains than hybrid genotypes with lower ROL. - Highlights: • Si addition significantly increased root and grain biomass. • Si addition significantly increased Fe plaque on rice roots of different genotypes. • Si addition significantly decreased As concentrations in rice roots, straws and husks. • Higher ROL genotypes induced more Fe plaque than lower ROL genotypes. • Si fertilization decreased DMA and iAs concentrations in rice grains. - Silicon application significantly increased rice biomass and Fe plaque on roots, and decreased total As and DMA in rice genotypes with different ROL.