Hollow silica microspheres with promising physical properties (MAT540TM) as support for enzyme immobilization and biocatalyst were investigated in this study. The amine-functionalized MAT540TM was activated by six bisepoxides inclosing different spacers and used as epoxy-functionalized carrier for immobilization of lipase B from Candida antarctica (CaLB). The novel, covalently fixed CaLB biocatalysts were compared in kinetic resolution (KR) of racemic 1-phenyethanol rac-1 and five racemic amines rac-3a-e using shaken flasks and continuous-flow packed-bed microreactors. Mechanic stability, re-usability and the effect of temperature (0–90 °C) on productivity and enantiomer selectivity of the covalently immobilized CaLB were investigated. The best performing CaLB biocatalyst showed good mechanic stability after 24 h operation time in continuous-flow mode at 60 °C and provided in KRs of racemic 1-phenyethanol rac-1 with vinyl acetate and of five racemic amines with isopropyl 2-ethoxyacetate as acylating agent the non-reacted (S)-alcohol [(S)-1] or (S)-amines [(S)-3a-e] and the forming (R)-ester [(R)-2] or (R)-amide [(R)-4a-e] in good yields with high enantiomeric excess (ee > 99 %, for all).
The purpose of this research was to investigate the impact of immigration on local ethnic groups' demographic weight (DW) by presenting a case study. In this study, the ethnic French Canadians (EFC), a group that makes up the majority of the Province of Quebec, were studied to evaluate the impact of immigration on their DW. It was found that EFC transitioned from a DW of 79% in 1971 to a DW of 64.5% in 2014; projections predict that EFC would decrease to a DW of 45% in 2050. Moreover, 45 immigration rate scenarios and total fertility rates were projected; it was found that immigration level and fertility level could be jointly classified into three categories related to their effect on ethno‐demographic decrease; one of these categories may help suggest a quantitative definition for the concept of mass immigration.
In quantitative PCR (qPCR), replicates can minimize the impact of intra-assay variation; however, inter-assay variations must be minimized to obtain a robust quantification method. The method proposed in this study uses Savitzky-Golay smoothing and differentiation (SGSD) to identify a derivative-maximum-based cycle of quantification. It does not rely on curve modeling, as is the case with many existing techniques. PCR fluorescence data sets challenged for inter-assay variations (different thermocycler units, different reagents batches, different operators, different standard curves, and different labs) were used for the evaluation. The algorithm was compared with a four-parameter logistic model (4PLM) method, the C0 method, and the threshold method. The SGSD method compared favourably with all methods in terms of inter-assay variation. SGSD was statistically different from the 4PLM (P = 0.03), C0 (P = 0.05), and threshold (P = 0.004) methods on relative error comparison basis. For intra-assay variations, SGSD outperformed the threshold method (P = 0.005) and equalled the 4PLM and C0 methods (P > 0.05) on relative error basis. Our results demonstrate that the SGSD method could potentially be an alternative to sigmoid modeling based methods (4PLM and C0) when PCR data are challenged for inter-assay variations.
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