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Bearing is one of the most important component of rotary machine, and its health state is directly related to the safety of industrial production. In this paper, health state assessment of bearing is investigated with feature enhancement and prediction error compensation. Specially, health state assessment consists of time-to-start prediction point detection and remaining useful life (RUL) prediction. In the first stage, variance feature based on Kalman filter is introduced to detect the time-to-start prediction point. Subsequently, complete ensemble empirical mode decomposition with adaptive noise is employed to reconstruct the degradation trend, and cumulative function is adopted to realize the feature enhancement, then efficient health indicator can be constructed. In the RUL prediction stage, degradation model and adaptive extended Kalman filter are fused to achieve the prediction, and bidirectional gated recurrent unit neural network is chosen to compensate the prediction error. Finally, experimental studies based on PRONOSTIA and XJTU-SY datasets are conducted to validate the effectiveness of the proposed method and its superiority over the traditional methods. • The proposed method provides a new solution to determine the prediction start time. • The cumulative function is used to establish the trend health indicator. • The adaptive EKF and Bi-GRU are fused to predict the RUL of bearing. • Different bearing datasets are used to verify the effectiveness of proposed method. [ABSTRACT FROM AUTHOR]

Monoterpenes are the most important contributors to the floral and fruity flavor of Muscat grapes. However, loss of Muscat flavor and decreased quality during shelf life often affect the commercial value of grapes. Light radiation can be an effective tool to maintain postharvest quality. In the present study, the effect of different wavelengths of light (white, red, blue, red–blue, UV-A and UV-B) on the quality of 'Shine Muscat' (Vitis labrusca × vinifera) during the shelf life was carried out. Grapes irradiated with white, red, blue and red‒blue light showed degraded chlorophyll and accumulated carotenoids in the skin compared to grapes under dark conditions. Blue and red‒blue light were more effective than other wavelengths of light in maintaining and increasing the levels of monoterpenes, such as linalool, limonene, and geraniol. Blue light exhibited the best maintenance and promotion effects on overall quality based on principal component analysis, and promoted the expression of some key genes involved in monoterpene synthesis, such as VvPNLinNer 1, VvPNLinNer 2, VvTPS60 and VvPNLNGL4. The transient over-expression experiment revealed that VvTPS60 may be primarily responsible for catalyzing the linalool synthesis. Results suggest that exposing postharvest grapes to different wavelengths of light is a promising technology to improve fruit quality. [Display omitted] • Blue and red–blue lights increased the content of most monoterpens in grapes. • Postharvest light could up-regulate the expression of monoterpene biosynthetic genes. • Bule light had the best maintenance and promotion effects on overall grape quality. • VvTPS60 may be primarily responsible for catalyzing the linalool biosynthesis. [ABSTRACT FROM AUTHOR]

Abstract Antimicrobial peptides (AMPs) play essential roles in the innate immune system to protect against a wide variety of pathogens in aquatic environments. In this study, three very important AMPs, cathelicidin, hepcidin and defensin, were identified in the critically endangered Acipenser dabryanus. The full-length cDNA sequences of these three AMPs were identified from transcriptome sequencing and the rapid amplification of cDNA ends (RACE) technique. Phylogenetic analysis showed that cathelicidin formed a clade with the other members of the cathelicidin family, and similar results were obtained for hepcidin. The A. dabryanus β-defensin belonged to the fish class 2 β-defensins. A tissue distribution study showed that the three AMP transcripts could be detected constitutively in various tissues. The highest expression levels of cathelicidin and hepcidin were found in the liver, while defensin was primarily expressed in the skin. Bacterial challenge in vivo revealed significant changes in the gene expression of the three AMPs at both mucosal sites and systemic sites. Striking upregulation of cathelicidin and hepcidin was observed in the skin at 12 h post-challenge, with increases of more than 7000-fold and 1000-fold, respectively, compared to the control, and the expression of defensin mRNA was remarkably elevated in the hindgut (by 230-fold at 6 h post-challenge). Moreover, according to the expression profiles of the AMPs post-challenge, we found that the mucosal immune response occurred earlier than the systemic immune response following bacterial infection. Our results suggest that these three novel AMPs may play important roles in the innate immune system of A. dabryanus to protect against invading pathogens, especially during the mucosal immune response. Highlights • Three novel antimicrobial peptides (AMPs) were cloned and characterized from Acipenser dabryanus. • AMPs transcripts were detected in a wide range of tissues of healthy A. dabryanus. • Bacterial challenge in vivo revealed significant changes in the gene expression of the three AMPs. • The different expression patterns of AMPs between the mucosal and systemic tissues after bacterial challenge were studied. [ABSTRACT FROM AUTHOR]