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Due to its poor hydro-physical properties and other characteristics, argillaceous dolomite is susceptible to seepage failure under high water pressure, affecting the seepage stability of a rock mass. To ensure the safety of the project, when the argillaceous dolomite is present, it is necessary to study the conditions pertaining to its seepage failure. Taking the argillaceous dolomite of Jurong Pumped Storage Power Station as the research object, the spatial distribution, occurrence, scale, degree of weathering, and mechanical and hydrogeological characteristics of the argillaceous dolomite were studied. Through on-site water pressure tests and laboratory variable head tests, the permeability characteristics of argillaceous dolomite were analyzed, and the hydraulic conductivity of the argillaceous dolomite in the upper reservoir and underground powerhouse areas was quantified. The argillaceous dolomite specimens were collected, and seepage failure tests were conducted to determine the critical water pressure for its seepage failure. Based on the results of the laboratory tests, a numerical model of groundwater flow was established. By changing the water level of the upper reservoir and the measures of the anti-seepage and drainage, the seepage stability of the argillaceous dolomite was discussed. The actual water pressure of argillaceous dolomite in the underground powerhouse area was identified during the operation of the Jurong pumped-storage power station. The calculations show that when fully enclosed anti-seepage and drainage measures are taken for the underground powerhouse, the maximum head of water is 98 m, which is lower than the critical water pressure of seepage failure for the argillaceous dolomite. Therefore, no seepage failure will occur. The results provide a scientific basis for the anti-seepage and drainage design of the underground powerhouse area. [ABSTRACT FROM AUTHOR]

A research study was conducted to establish if the side chain length of ubiquinone (UQ), which is determined by the nature of the polyprenyl diphosphate synthase, plays an important role in the metabolism of the cells. Cloning of the solanesyl diphosphate synthase gene from Rhodobacter capsulatus SB1003 was done to know the role of the side chain length of UQ. After the cloning process, it was expressed in Eschericia coli and Saccharomyces cerevisiae. Results showed the the side chain length of UQ has little role for the survival of microorganisms.

The Escherichia coli ispB-disrupted mutants were analyzed to determine the function of the ispB gene and its octaprenyl diphosphate synthase in microbial growth. The defects of the ispB-disrupted mutants were complemented by Haemophilus influenzae and Synechocystis sp. strain PCC6803 ispB homologs. Furthermore, the viability of the ispB gene disruptants was dependent on the presence of a plasmid-borne copy of the ispB gene.

We successfully isolated Rhodococcus sp. D-1, an efficient carbendazim-degrading bacterium that degraded 98.20% carbendazim (200 ppm) within 5 days. Carbendazim was first processed into 2-aminobenzimidazole, converted to 2-hydroxybenzimidazole, and then further mineralized by subsequent processing. After genomic analysis, we hypothesized that D-1 may express a new kind of enzyme capable of hydrolyzing carbendazim. In addition, the effect of the biodegradable biosurfactant rhamnolipid on the rate and extent of carbendazim degradation was assessed in batch analyses. Notably, rhamnolipid affected carbendazim biodegradation in a concentration-dependent manner with maximum biodegradation efficiency at 50 ppm (at the critical micelle concentration, CMC) (97.33% degradation within 2 days), whereas 150 ppm (3 CMC) rhamnolipid inhibited initial degradation (0.01%, 99.26% degradation within 2 and 5 days, respectively). Both carbendazim emulsification and favorable changes in cell surface characteristics likely facilitated its direct uptake and subsequent biodegradation. Moreover, rhamnolipid facilitated carbendazim detoxification. Collectively, these results offer preliminary guidelines for the biological removal of carbendazim from the environment. [ABSTRACT FROM AUTHOR]

In this study, the efficiency of the nonylphenol polyethoxylates (NPEOs)-degrading bacterium Sphingomonas sp. strain Y2 was evaluated, which was immobilized by a novel system composed of polydopamine (PD)-coated Fe 3 O 4 iron nanoparticles (IONPs). The PD-IONPs, with a distinct core-shell structure, relatively uniform size, and high saturation magnetization, were prepared for Y2 immobilization. The performance of Y2 was unaffected by this novel immobilization method, exhibiting 79.5% and 99.9% of NPEOs (500ppm) degradation efficiency at day 1 and 2, respectively. Furthermore, separation and recycling were more readily achieved for immobilized cells as compared to free cells. Immobilized cells retained over 70% of the original degradation activity after 6cycles of utilization. These results suggest that Y2-PD-IONPs can be potentially used for NPEOs-contaminated wastewater bioremediation., Capsule: Immobilization of Sphingomonas sp. Y2 by functionalized PD-IONPs with easy separation, recycling utilization and high efficiency., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Mitochondrial disease is a group of disorders caused by dysfunctional mitochondria, of which the mutation in the mitochondrial DNA is one of the primary factors. However, the molecular pathogenesis of mitochondrial diseases remains poorly understood due to lack of cell models. Patient-specific induced pluripotent stem cells (iPS cells or iPSCs) are originated from individuals suffering different diseases but carrying unchanged disease causing gene. Therefore, patient-specific iPS cells can be used as excellent cell models to elucidate the mechanisms underlying mitochondrial diseases. Here we present a detailed protocol for generating iPS cells from urine cells and fibroblasts for instance, as well as a series of characterizations.