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Coaxial coupling between two quasi-perfect ultrasonic vortices (QPUVs) with distinct ring radii and topological charges (TCs) has been suggested and implemented to create ultrasonic braided ring beams (UBRBs). It is possible to switch between a double-ring pattern, a braided ring pattern, and a petal-like pattern in the linked ultrasonic field distribution by varying the coupling strength of two QPUVs. We focus on the braided ring pattern and investigate the influence of TCs on the acoustic intensity and phase distributions. It is found that the UBRB contains multiple individual phase singularities, and the number of singularities is determined by the TCs of the two QPUVs. Furthermore, a phase modulation metasurface (PMM) composed of photosensitive resin cubes is well designed to produce the UBRB in water. The effectiveness of the single-layer PMM in producing the UBRB is confirmed by both simulations and experimental results. The proposed UBRBs based on metasurfaces could potentially have uses in multi-particle manipulation and acoustic communication. [ABSTRACT FROM AUTHOR]

Objectives: To screen the phylogenetically-nearest members of Cellulosimicrobium cellulans for the production of cellulosome-like multienzyme complexes and extracellular β-xylosidase activity against 7-xylosyltaxanes and to get corresponding molecular insights.Results: Cellulosimicrobium (family Promicromonosporaceae) and all genera of the family Cellulomonadeceaec produced both cellulosome-like multienzyme complexes and extracellular β-xylosidase activity, while the other genera of the family Promicromonosporaceae did not. Multiple sequence alignments further indicated that hypothetic protein M768_06655 might be a possible key subunit.Conclusion: This is the first report that many actinobacteria species can produce cellulosome-like multienzyme complexes. The production of cellulosome-like complexes and the extracellular β-xylosidase activity against 7-xylosyltaxanes might be used to differentiate the genus Cellulosimicrobium from other genera of the family Promicromonosporaceae. [ABSTRACT FROM AUTHOR]

In this study,a method using ultra performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry( UPLC-Q-TOF-MS/MS) was established to identify complicated chemical constituents of Wikstroemia indica. Chromatographic separation was performed on an AcclaimTMRSLC 120-C18 column( 2. 1 mm×100 mm,2. 2 μm) using gradient elution with 0. 2% ammonium formate buffer salt solution( A)-0. 2% ammonium formate buffer salt solution methanol( B) as mobile phase. The column temperature was maintained at 30 ℃. The analytes were determined by positive and negative ion modes with electro-spray ionization source. A total of 52 compounds( including eleven coumarins,thirteen flavonoids,ten lignans,two amides,four phenolic acids,six sesquiterpenes and six other compounds) were identified or tentatively characterized from the water extract of W. indica by comparing their retention times and MS spectra with those of authentic standards or literature datas. Three compounds were found for the first time from W.indica namely isomer of indicanone,β-hydroxypropiovanillone and epiprocurcumenol. Furthermore,the fragmentation rules of some compounds were speculated and summarized. In addition,the cleavage pathways of guaiane sesquiterpenes were described for the first time,which can provide reference for studying the fragmentation pathways of similar compounds. This study provides an easy way to identify chemical constituents of traditional Chinese medicine and a basis for the further study on chemical fundamentals of W. indica.