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In this study, the effects of high-pressure homogenization (HPH) (20, 60, and 100 MPa) on the structure, microstructure, and functional properties of oyster (Crassostrea gigas) protein (CGP) were investigated. Circular dichroism examination showed that the secondary structure of oyster proteins became loose and that the alpha-helix transformed into a random coil structure. The fluorescence spectra had a redshift from 350 nm to 360 nm, exposing the chromophore and changing the tertiary structure of CGP. With the increase in homogeneous pressure, HPH significantly reduced particle sizes of CGP. Compared to other treatments, HPH at 100 MPa showed a higher surface hydrophobic index (86.84), solubility (84.7%), and water holding capacity (15.2 g/g). However, the emulsion activity index (137.5 m(2)/g) and foaming ability (113.3%) were best at a lower pressure (20 MPa). The scanning electron microscope showed that HPH treatment could improve emulsion stability. This work demonstrates that HPH treatment has a positive impact on the physicochemical and functional properties of CGP for potential industrial applications.

Hox and ParaHox genes encode transcription factors with similar expression patterns in divergent animals. The Pdx (Xlox) homeobox gene, for example, is expressed in a sharp spatial domain in the endodermal cell layer of the gut in chordates, echinoderms, annelids and molluscs. The significance of comparable gene expression patterns is unclear because it is not known if downstream transcriptional targets are also conserved. Here, we report evidence indicating that a classic transcriptional target of Pdx1 in vertebrates, the insulin gene, is a likely direct target of Pdx in Pacific oyster adults. We show that one insulin-related gene, cgILP, is co-expressed with cgPdx in oyster digestive tissue. Transcriptomic comparison suggests that this tissue plays a similar role to the vertebrate pancreas. Using ATAC-seq and ChIP, we identify an upstream regulatory element of the cgILP gene which shows binding interaction with cgPdx protein in oyster hepatopancreas and demonstrate, using a cell culture assay, that the oyster Pdx can act as a transcriptional activator through this site, possibly in synergy with NeuroD. These data argue that a classic homeodomain-target gene interaction dates back to the origin of Bilateria. In vertebrates insulin is a direct transcriptional target of Pdx: the same is true in Pacific oysters and the authors show insulin-related gene, cgILP, is co-expressed with cgPdx in oyster digestive tissue, showing this gene interaction dates back to the origin of Bilateria., source:https://www.nature.com/articles/s41467-021-23216-7

Field random vibration is usually non-Gaussian, which makes ordinary random vibration testing unable to simulate the fatigue damage that products will experience in field. A new method is proposed in this paper to synthesize running RMS-induced non-Gaussian vibration based on the probability distribution of running RMS (root mean square), which is simulated by using the two-parameter Weibull distribution. Shock response spectrum (SRS) is used to detect significant transients within signals. The synthesized non-Gaussian signal has the same PSD, kurtosis and PDF (probability density function) as the field data. Fatigue damage spectrum (FDS) is used as another proof of the effectiveness of this proposed new method.

Field random vibration is usually non-Gaussian, which makes ordinary random vibration testing unable to simulate the fatigue damage that products will experience in field. A new method is proposed in this paper to synthesize running RMS-induced non-Gaussian vibration based on the probability distribution of running RMS (root mean square), which is simulated by using the two-parameter Weibull distribution. Shock response spectrum (SRS) is used to detect significant transients within signals. The synthesized non-Gaussian signal has the same PSD, kurtosis and PDF (probability density function) as the field data. Fatigue damage spectrum (FDS) is used as another proof of the effectiveness of this proposed new method.

Edited trans. of Guoji Hangkong (China) n7 p8-11 Jul 80.