Search

Isoflavones are the major bioactive components in soybeans. Sequential window acquisition of all theoretical fragment ions (SWATH) is a kind of data-independent acquisition (DIA), such that all fragments of each precursor will be preserved in a SWATH-Mass Spectrometry (SWATH-MS) run. In this study, a high-throughput SWATH-MS method for the determination of 12 isoflavones in soybeans was established. Furthermore, amino acids, saponins can be semi-quantitated from the same SWATH-MS data. Combination of targeted quantification and untargeted profiling with SWATH, all bioactive compounds were analyzed within 5 min in 10 min run time, and the method had good linear regression with r2 > 0.99. The precisions (RSD %) of the intra-day and inter-day analyses ranged from 2.11% to 18.7%, and the accuracies (RE%) ranged from −14.39% to 17.48%. The matrix effect ranged from 88.66% to 114.82%. Moreover, 7 varieties of soybeans were analyzed and compared with this robust screening method.

The ancient European mechanical clock with automata is one of the indicators of manufacturing technology, and the clocks exported to Asia offer evidence of cultural exchange at that time. The Gilded Copper Rising and Falling Pavilion Clock Inlaid with Gemstones is one of the ingenious mechanical work made in Britain and exported to China in the 18th century. Although it's well preserved in the Forbidden City in Beijing (Palace Museum currently), the internal mechanical structure is not open to the public, because of its historical value. In order to reconstruct the pagoda automaton attached to the clock, structural analysis is presented according to the text records of the other four clocks with similar automata. A systematic design approach is proposed herein. The feasible mechanisms are synthesized by going through generalization, specialization, and particularization. As the result, nine, three, and four feasible mechanisms with linkage, gear, and cam are generated, respectively. One of the feasible designs with the largest output motion range is selected, and dimensional synthesis is made to achieve the motion characteristics. Its performance is verified through prototype testing.

The generation of recombinant antibodies (Abs) using phage display is a proven method to obtain a large variety of Abs that bind with high affinity to a given antigen. Traditionally, the generation of single-chain Abs depends on the use of recombinant proteins in several stages of the procedure. This can be a problem, especially in the case of cell-surface receptors, because Abs generated and selected against recombinant proteins may not bind the same protein expressed on a cell surface in its native form and because the expression of some receptors as recombinant proteins is problematic. To overcome these difficulties, we developed a strategy to generate single-chain Abs that does not require the use of recombinant protein at any stage of the procedure. In this strategy, stably transfected cells are used for the immunization of mice, measuring Ab responses to immunization, panning the phage library, high-throughput screening of arrayed phage clones, and characterization of recombinant single-chain variable regions. This strategy was used to generate a panel of single-chain Abs specific for the innate immunity receptor Toll-like receptor 2. Once generated, individual single-chain variable regions were subcloned into an expression vector allowing the production of recombinant Abs in insect cells, thus avoiding the contamination of recombinant Abs with microbial products. This cell-based system efficiently generates Abs that bind to native molecules on the cell surface, bypasses the requirement of recombinant protein production, and avoids risks of microbial component contamination.