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A broad-spectrum antimicrobial peptide named Paracin 1.7 was produced by Lactobacillus paracasei HD1.7, which was isolated from Chinese sauerkraut juice. In this study, the influence of cocultivation on the communication mechanism of L. paracasei HD1.7 and Bacillus subtilis was investigated. The two bacterial strains were grown in monoculture and indirect coculture, and the growth of both bacteria and bacteriocin production as well as the transcriptional level of luxS in L. paracasei HD1.7 and spo0A in B. subtilis were monitored. Bacteriocin production and cell numbers were increased significantly when L. paracasei HD1.7 cells were indirectly cocultured with B. subtilis, and bacteriocin-producing L. paracasei HD1.7 can prevent the growth and sporulation of B. subtilis. After indirect coculture with B. subtilis, the expression of luxS in L. paracasei HD1.7 increased in the exponential growth phase and decreased in the stationary phase compared to monoculture. The expression of spo0A in B. subtilis dropped in the indirect coculture compared to the monoculture. It indicate that the upregulation of luxS is due to a response to a secreted compound produced by B. subtilis. The results show L. paracasei HD1.7 has an amensalism on B. subtilis, while B. subtilis has a commensalism on L. paracasei HD1.7.

[Image: see text] In order to improve the antitumor potency of the natural product evodiamine, novel boron-containing evodiamine derivatives were designed by incorporating boronic acid and boronate as trigger units. Boronate derivative 13a could be triggered by reactive oxygen species (ROS) in the HCT116 colon cancer cell line and showed excellent antitumor activity in vitro and in vivo. It induced apoptosis in HCT116 cancer cells in a dose-dependent manner and cell growth arrest at the G2 phase.

This paper presents a comparative study of the tribological and vibration performance of the synthesized lithium complex grease (LCG) containing Carbon black, Fe3O4 and Al2O3 nanoparticles on rolling bearing. The micromorphology, friction coefficient, worn surface and bearing vibration experiment of four greases were studied. The results show that in presence of nanoparticles friction and wear behaviors are improved compared to LCG without nanoparticles. The best tribological performance is obtained in presence of Al2O3 nanoparticle, which is mainly attributed to its high hardness, cylindrical shape and deposition on the worn surface. Further, the wettability test shows that Al2O3 nanoparticles can effectively promote the flow of base oil on the LCG soap fibers, which results in the most effective bearing vibration suppression.

To evaluate the effects of CuO nanoparticles on friction and vibration behaviors of grease on rolling bearing, lithium complex grease (LCG), polyurea grease (PG), calcium sulfonate complex grease (CSCG) and these three greases containing 1 wt% CuO nanoparticles were prepared respectively. The microstructure, friction coefficient, wear surface and bearing vibration test of six greases were investigated in detail. The results show tribological properties of PG are improved most significantly, with the friction coefficient and wear scar diameter decrease, and the wear surface is fine and smooth. This is mainly attributed to the synergistic effect of lamellar thickener structure and CuO nanoparticles. Further, the addition of CuO nanoparticles to PG also has an obvious inhibitory effect on bearing vibration.

The co-culture of microorganisms involves at least two microorganisms or more in an environment of confined conditions, which is induced by microbe communities that are ubiquitous in nature. Therefore the attentions of people are increasingly attracted to utilize the co-culture approach in many fields. The growth of microorganisms should be detected starting from the isolation medium and each of them should be recorded respectively which are of significant importance in the process of co-culture. In this paper, L.paracasei HD1.7 and B.subtilis were applied to establish the isolation method. The growth of each of them was determined in MRS and BP medium. The results demonstrated that L.paracasei HD1.7 was not able to grow on BP medium cultivated at 37 °C for 36h, while B.subtilis could not grow on MRS medium incubated at 37 °C for 30h. Keywords-co-culture, L.paracasei HD1.7and B.subtilis, isolation method

An ethylene-propylene copolymer (EPM) has been functionalized with acrylic acid (AA) by means of a radical-initiated melt process. Different degrees of grafting have been obtained by varying the overall composition of the reaction mixture. The influence of the grafting degree on the structure has been investigated by differential scanning calorimetry (DSC), Fourier-transform infrared analysis (FTIR), and wide-angle x-ray scattering (WAXS) techniques. The results of the structural investigations suggest that the grafting preferentially occurs onto the ethylene sequences of EPM. After acrylic acid was grafted onto EPM, the grafted AA acted as nucleation agent; it caused an increase of crystallization temperature of propylene sequences of EPM-g-AA.

'Yi 4060' is an elite restorer line of a non-photoperiod-sensitive D 2 -type cytoplasmic male-sterile (CMS) line of wheat. Random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers were employed to map one major fertility-restoring gene (D 2 Rf 1 ) in 'Yi 4060'. The sterile and fertile DNA pools were established from individuals in BC 6 , based on bulked segregant analysis. One RAPD marker E09, linked to D 2 Rf 1 , was converted to a SCAR marker and designated as E09-SCAR 865 . The genetic distance between E09-SCAR 865 and D 2 Rf 1 is 9.5 cM. Two SSR markers, Xgwm11 and Xgwm18, were also linked to a D 2 Rf 1 and co-segregated with E09-SCAR 865 . The three molecular markers are useful in marker-assisted breeding of the elite restorer lines for D 2 -type CMS lines in wheat.