No abstract

Multiple myeloma (MM) is characterized by clonal proliferation of malignant plasma cells in the bone marrow. The anti-tumor activity of bortezomib (a proteosome inhibitor) in MM is challenged by emergence of drug resistance. MicroRNAs (miR) regulate and orchestrate multiple cellular pathways. We investigate the contribution miR-181a and miR-20a expressions' on cell proliferation and apoptosis in RPMI8226 cell line and their influence on bortezomib treatment. RNA isolation, quantitative real-time PCR (qRT-PCR), cell proliferation assay, cell cycle analysis, and cell apoptosis assay were done. Statistical analysis was performed using SPSS 17.0 software (SPSS, Chicago, IL, USA). P values of less than 0.05 were considered statistically significant. RPMI8226 cells seeded in 96-well plates and treated for 24 h with different concentrations of bortezomib showed dose-dependent growth inhibition; expression of both miR-181a and miR-20a were inhibited by bortezomib. We found decrease of miR-181a (60%) and miR-20a (30%) in cells transfected with 20-nM inhibitor. A relative increase of 14-fold in miR-181a and 11-fold in miR-20a was observed in cells transfected with mimics of the same concentration. Transient low expression of miR-181a/20a inhibited proliferation at day 4, and overexpression of miR-181a promoted proliferation. Cells transfected with miR-181a/20a inhibitor within day 4 showed lower survival rate, and low expression of miR-181a on the fourth day after transfection promoted apoptosis. Our findings suggest that miR-181a/20a has a higher expression in MM. miR-181-a expression is proportional to MM tumor burden and could be a biomaker for monitoring treatment. miR-20a shows the potential of a diagnostic biomarker.

The forecasting slope deformation potential is required to evaluate slope safety during open-pit mining, allowing us to formulate and promote effective emergency strategies in advance to prevent slope failure disasters. Although fractal models have been used to predict slope deformation, such limitations as low prediction accuracy, poor stability and the requirement for large amounts of data must be overcome. This article proposes an improved fractal model to forecast mine slope deformation using the grey system theory. The GM (1, 1) model is used in the improved fractal model to optimize the fitting function of the fractal dimension because of its high computational efficiency and strong fitting ability. Data sequences spanning 13 days from 11 global positioning system monitoring stations in the Jinduicheng open-pit mine in Shaanxi Province, China, were applied to forecast the slope deformation. The results from both the traditional fractal model and the improved fractal model can accurately forecast the slope deformation value fairly close to the actual field monitoring value, but the latter can make a more accurate prediction than the former. There is a significant relationship between the prediction accuracy and the data sequence dispersion. Further analysis revealed that our improved fractal model is more capable of resisting the volatility existing in the data sequences than the traditional fractal model. These findings assist in understanding the applicability of prediction models and the deformation trends of open-pit mine slopes.

No abstract

The ink-absorption capacity is an important factor for evaluating the printing quality of paper. In this study, the effects of different parameters of papermaking on the ink-absorption capacity of paper were investigated. The results showed that hardwood pulp exhibited better performance in increasing the absorptivity of paper compared with softwood pulp. When the content of hardwood pulp in paper was increased from 0% to 100%, the ink mark length decreased from 5.1 cm to 4.3 cm. Furthermore, a basis weight change from 100 g/m2 to 60 g/m2 increased the ink-absorption capacity, as revealed by a decrease of the ink mark length from 4.8 cm to 4.4 cm. Both sizing agent and beating degree affected the ink-absorption performance of the paper. For example, a shorter ink mark length of 5.1 cm was obtained at a low beating degree of 5000 r compared with that of 5.1 cm at 15000 r.