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Shaking is one of the key processes contributing to the quality formation of oolong tea. As an abiotic stress factor, mechanical stress leads to a series of physiological and biochemical changes in plants through various biological effects, which has been widely used in the processing of scented black tea, scented white tea, scented green tea and other tea types to improve their quality. In order to ascertain the physiological changes of green tea leaves in response to mechanical stress, postharvest fresh shoots with 3–4 leaves?from the tea cultivar ‘Tieguanyin’ were evaluated for changes in water content, photosystem II (PS II) parameters, antioxidant enzyme activities and subcellular structure under natural spreading or continuous vibration stress treatment after withering. Compared with naturally spread leaves and withered leaves, the water content in the leaves subjected to vibration stress was not significantly different within the first 30 min of vibration (P > 0.05) but was significantly lower at 60 min (P < 0.05). The green-grassy odor became stronger with increasing vibration time, the refreshing aroma became weaker, and the clear compact lamellar structures of the chloroplast and the thylakoid were gradually loosened, deformed, shrunk, and disrupted. The number of starch granules increased significantly at 5 min, and the number of osmiophilic granules increased significantly at 15 min, resulting in the formation of aggregates. The actual photosynthetic efficiency Y (II) and photochemical quenching coefficient (qP) of PS II generally showed a decreasing trend with increasing vibration time, and the electron transfer rate (ETR) declined initially and then rose. The Y (II) and ETR at 5 and 10 min of vibration were significantly lower than those observed in naturally spread leaves (P < 0.05). The quantum yield Y (NO) of non-regulated energy dissipation increased with the prolongation of vibration stress treatment time, and was significantly higher than that of naturally spread leaves at 30 min (P < 0.05). The relative conductivity of tea leaves under vibration stress for 10 min was significantly higher than that of naturally spread leaves (P < 0.05). The activities of ascorbate peroxidase, dehydroascorbate reductase and glutathione reductase in tea leaves under vibration stress for 5 and 10 min were higher than those in naturally spread leaves. Vibration treatment (for up to 30 min) did not show significant variations in water content, but enhanced the green-grassy odor. Continuous vibration treatment caused cell injuries by increasing the cell membrane permeability, thereby facilitating the release of intracellular contents and increasing cell conductivity. At the subcellular level, vibration treatment promoted thylakoid degradation and severely damaged chloroplasts, thus destroying PS II stability. Meanwhile, it protected tea leaf cells against mechanical stress-induced damage by elevating the activities of defense enzymes. Taken together, this study lays a foundation for the regulating of shaking during the processing of oolong tea.

Matsutake mushrooms, known for their high value, present challenges due to their seasonal availability, difficulties in harvesting, and short shelf life, making it crucial to extend their post-harvest preservation period. In this study, we developed three quality predictive models of Matsutake mushrooms using three different methods. The quality changes of Matsutake mushrooms were experimentally analyzed under two cases (case A: Temperature control and sealing measures; case B: Alteration of gas composition) with various parameters including the hardness, color, odor, pH, soluble solids content (SSC), and moisture content (MC) collected as indicators of quality changes throughout the storage period. Prediction models for Matsutake mushroom quality were developed using three different methods based on the collected data: multiple linear regression (MLR), support vector regression (SVR), and an artificial neural network (ANN). The comparative results reveal that the ANN outperforms MLR and SVR as the optimal model for predicting Matsutake mushroom quality indicators. To further enhance the ANN model's performance, optimization techniques such as the Levenberg–Marquardt, Bayesian regularization, and scaled conjugate gradient backpropagation algorithm techniques were employed. The optimized ANN model achieved impressive results, with an R-Square value of 0.988 and an MSE of 0.099 under case A, and an R-Square of 0.981 and an MSE of 0.164 under case B. These findings provide valuable insights for the development of new preservation methods, contributing to the assurance of a high-quality supply of Matsutake mushrooms in the market. [ABSTRACT FROM AUTHOR]

In simple mechanical events, we can directly perceive causal interactions of the physical objects. Physical cues (especially spatiotemporal features of the display) are found to associate with causal perception. Here, we demonstrate that cues of a completely different domain--"social cues"--also impact the causal perception of "physical" events: The causally ambiguous events are more likely to be perceived as causal if the faces superimposed on the objects change from neutral to fearful. This effect has the following major properties: (a) The effect is caused by social information because it disappears when the faces are inverted or when the expression changes are unreasonable; (b) the social cues are integrated in a temporal window different from physical cues; and (c) the social cues impact the perception process rather than the decision process as the impact also appears in the causality-induced illusion. These findings suggest that the visual system relies on social information to infer the causal structure of the physical world. (Contains 6 figures and 4 footnotes.)

Human endogenous retroviruses (HERVs) are estimated to comprise ∼8% of the entire human genome, but the vast majority of them remain transcriptionally silent in most normal tissues due to accumulated mutations. However, HERVs can be frequently activated and detected in various tissues under certain conditions. Nucleic acids or proteins produced by HERVs can bind to pattern recognition receptors of immune cells or other cells and initiate an innate immune response, which may be involved in some pathogenesis of diseases, especially cancer and autoimmune diseases. In this review, we collect studies of the interaction between HERV elements and Toll-like receptors and attempt to provide an overview of their role in the immunopathological mechanisms of inflammatory and autoimmune diseases. [ABSTRACT FROM AUTHOR]

Functional supramolecular gel materials have potential applications in sensors, optical switches, artificial antennae, drug delivery and so on. In this paper, quinoline‐cored poly(aryl ether) dendritic organogelators were designed, synthesized and fully characterized. The gelation behaviour of the dendritic organogelator was tested in organic solvents, mixed solvents and ionic liquids. The dendron Q‐G1 was found to be an efficient and versatile organogelator toward various apolar and polar organic solvents with the critical gelation concentrations (CGCs) approaching 1.2×10−2 mol/L, indicating one dendritic organogelator could immobilize 1.2×103 solvent molecules in the organogel network. Interestingly, these dendrons exhibited excellent gel formation in ionic liquids. Notably, these dendritic organogels were found to display multiple stimuli‐responsive properties toward external stimuli including heat, ultrasound and shear stress, with a reversible sol‐gel phase transition. In addition, the dendritic organogel could effectively adsorb heavy metals and organic dyes. The removal rate of Pb2+ was up to 20% and the adsorption rate for Rhodamine B was as high as 89%. [ABSTRACT FROM AUTHOR]