Bacillus subtilis is widely used for large-scale industrial production of heterologous proteins. Because of its high intrinsic secretory capacity, it can efficiently secrete proteins into the culture supernatant via the general Sec-type secretion pathway. In this study, the α-amylase AmyS was used as a reporter to construct a library encompassing 173 Sec-type signal peptides (SPs) from B. subtilis using a fast, sequence-independent method. The resulting library DNA which harbored different signal peptides in the expression vector was used to transform B. subtilis directly at high efficiency, and 15 SPs which produced a significantly increased yield of AmyS were identified using a starch-iodine-based high-throughput assay. Furthermore, the correlation between the sequences of the best-performing signal peptides and their secretion efficiency was analyzed, which revealed several common properties of these SPs. Finally, high-cell-density fermentation of the α-amylase-producing strain with the best-performing signal peptide yielded a maximum of 5086 U/mL amylase at 66 h with a high productivity of 77.1 U/mL·h.

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Though the Pareto/NBD (developed by Schmittlein et al. 1987) is a powerful model for customer base analysis, it is difficult to implement especially in terms of parameter estimation. In this paper, the authors propose a MCMC algorithm for model estimation, and a Monte Carlo simulative approach to calculate key results of the model. The outcome of the method is a measure in which value is operationalized as a probability distribution, in contrast to previous studies has actually computed a spot estimation. The algorithm is applied into two direct marketing datasets and gets close parameter estimates with MLE. By implementing MC simulation, the study also shows a good interval predictive performance of the Pareto/NBD. Further more, the authors propose three possible extensions to the Pareto/NBD model and derive a GG/NBD model as a generalization to the Pareto/NBD.

The objective of the present study was to investigate the anticancer activity of Chinese medicine Caulis Spatholobi extract on multicentric osteosarcoma cells. Ultraviolet spectrophotometry was used to determine the total flavonoid content in each sample; vanillin sulphuric acid assay was used to determine the condensed tannin content in each sample; and the varying degrees of inhibitory activities of ethanol, ethyl acetate and n-butanol extracts of Caulis Spatholobi on human osteosarcoma Saos-2 cells were studied. The results showed that the inhibitory activity of ethyl acetate extract was the highest among the four extracts. The condensed tannin contents of 1.2 mg/mL Caulis Spatholobi water extract, ethanol extract, ethyl acetate extract and petroleum ether extract were 26.23%, 48.36%, 70.18% and 40.51% respectively; and condensed tannin content of 1.5 mg/mL Caulis Spatholobi water extract, ethanol extract, ethyl acetate extract and petroleum ether extract were 4.15%, 5.81%, 8.76% and 7.30% respectively.

349outcomes of Latina/o students were investigated. The students enrolled in branch campuses of the Indiana and Purdue systems were the most likely to drop out of the college, with the effect being greatest for the Latinas/os who were more three times more likely to leave than the African Americans and almost 1.5 times more likely to leave than all other students. The students enrolled at urban campuses were also more likely to leave, except for the Latinas/os. Overall, the Latina/o students experienced less success at regional campus and campuses that serve a higher proportion of students of color and more success at campuses with higher proportions of faculty of color. (87 ref)-Department of Leadership Studies,

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