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Because of high moisture content, blueberries are susceptible to disease and insect infestation leading to corruption and deterioration, which has serious influence on the shelf life of blueberry fruits. This article summarizes the cause mechanism of postharvest quality deterioration of blueberry fruits and the research progress of blueberry preservation technology at home and abroad, mainly including physical, chemical and biological preservation methods; and emphasizes the application of biological methods in the postharvest preservation of blueberries.

In order to study the key flavor characteristics and the influence of oxidation degree of oil on warmed-over flavor of pre-prepared steamed pork with preserved vegetable. The volatile flavor compounds and taste indexes of different brands of pre-prepared steamed pork with preserved vegetable were quantitatively detected by headspace-solid phase micro- extraction-gas chromatography-mass spectrometry and electronic tongue. The key flavor factors of pre-prepared steamed pork with preserved vegetable were screened and analyzed by odor activity value (OAV) and principal component analysis. Acid value, peroxide value and TBA value were used to analyze the oxidation degree of oil and warmed-over flavor of different brands of pre-prepared steamed pork with preserved vegetable. Results showed that a total of 85 volatile compounds were identified from 7 kinds of pre-prepared steamed pork with preserved vegetable, including 16 alkanes, 19 terpenes, 7 alcohols, 22 aldehydes, 3 ketones, 13 esters, 3 phenols and 2 others. A total of 23 key volatile compounds were screened by OAV, and the substances with OAV>10 were 1-octene-3-ol, hexanal, heptanal, octanal, nonanal, (E,E)-2,4- nonadienal, capric aldehyde, (E)-2-decenal, (E,E)-2,4-decenal and 1-octene-3-ketone, which were the key flavor substances for pre-prepared steamed pork with preserved vegetable. The results of electronic tongue and overripe taste evaluation showed that the taste of 7 kinds of pre-prepared steamed pork with preserved vegetable were mainly salty, umami and aftertaste. Its overripe taste mainly presented linseed oil taste and rancidity taste. The oil oxidation indexes of 7 kinds of pre-prepared steamed pork with preserved vegetable were higher and the differences were significant (P<0.05). The correlation analysis showed that the main factors that produce warmed-over flavor were (E)-2-decenal, 2-heptanone, nonylaldehyde, 1-octene-3-ketone, (E,E)-2,4-decenal, hexal, pentaldehyde, heptanal, (E)-2-heptenal and octanal, which were positively correlated with acid value, peroxide value and TBA value. In summary, the key flavor factors of the 7 kinds of pre-prepared steamed pork with preserved vegetable were related to overcooked taste, and it was speculated that the overcooked taste of pre-prepared steamed pork with preserved vegetable was related to the higher oxidation degree of oil. The key flavor factors, electronic tongue and overripe taste evaluation indexes obtained in this study provide the basis for the establishment of flavor quality system and overripe taste control of pre-prepared steamed pork with preserved vegetable. [ABSTRACT FROM AUTHOR]

It is found for the first time that ferrocene (Fc) can be used as a peroxidase mimic to catalyze the oxidation of hydrogen peroxide (H2O2) in this experiment. Hydroxyl radicals (OHṖ), one product from oxidation reactions, oxidizes TMB (colorless solution) to TMBOX (blue solution). Double-reciprocal plots present that the catalysis mechanism of Fc in H2O2 oxidation is consistent with the ping-pong mechanism. Additionally, Fc was successfully utilized for polyaniline (PANI) microsphere synthesis in the presence of H2O2. Compared with the control, better physical and chemical properties of PANI synthesized in the presence of Fc are found in this study. [ABSTRACT FROM AUTHOR]

MicroRNA (miR)-140-5p is associated with the growth and metastasis of various tumor cell types, yet its role in multiple myeloma (MM) remains unclear. Therefore, the present study aimed to investigate the regulatory effect of miR-140-5p on MM. Reverse transcription-quantitative PCR analysis demonstrated that miR-140-5p was downregulated in MM cell lines, particularly in U266 and RPMI 8226 cells. A Cell Counting Kit-8, wound healing and Transwell assays, as well as flow cytometry indicated that a miR-140-5p mimic could suppress cell viability, migration and invasion. In addition, the mimic promoted apoptosis of U266 and RPMI 8226 cells. Western blot data demonstrated that transfection with miR-140-5p mimic significantly reduced the expression levels of Ki-67, cyclin D1, vimentin, Snail, matrix metalloproteinase (MMP)-2 and MMP-3. Moreover, as predicted by TargetScan7.2 and verified by luciferase activity assay, it was demonstrated that vascular endothelial growth factor A (VEGFA) was targeted by miR-140-5p. Further experiments indicated that VEGFA overexpression promoted cell viability, migration and invasion and suppressed apoptosis of MM cells, and that the miR-140-5p mimic partially reversed the effects of VEGFA overexpression. Therefore, miR-140-5p suppressed MM progression by targeting VEGFA. The present findings provide insight into potential therapeutic strategies for the treatment of MM. [ABSTRACT FROM AUTHOR]

Air pollution is the result of enormous emissions and unfavorable meteorological conditions. The role of meteorology, particularly extremely unfavorable meteorological events (EUMEs), in processing atmospheric PM 2.5 pollution has not been fully addressed. This work examined the variations of PM 2.5 mass and its chemical components associated with various meteorological parameters and three EUMEs based on meteorological observations and analysis combined with one-year long in situ measurement in 2018 in the suburban area of Tianjin, China. Analysis shows that the polluted days in 2018 were mostly related to the increase in sulfate, nitrate, and ammonium (SNA). Temperature between -2 to 13 °C is more favorable for the formation of SNA, while high temperature exceeding 28 °C is favorable for the formation of organic carbon and sulfate. Most of the ions and carbon components showed significant increase in concentrations when relative humidity exceeded 80%. The maximum decreasing rate of PM 2.5 concentrations due to increase in wind speed and planetary boundary height could be 15.35 μg m -3 (m s -1 ) -1 , and 34.37 μg m -3 (100 m) -1 , respectively. EUMEs showed significant impacts on PM 2.5 components, in which PM 2.5 concentrations showed the most significant increase under temperature inversion (TI) events, and surface-based TI (SBTI) events usually have much stronger impacts on PM 2.5 concentrations than elevated TI (ELTI). Nitrate was found to be the most sensitive component to EUMEs, especially under multiple EUMEs. The synthetic effects of multiple EUMEs could result in an increase of nitrate by 35.53 μg m -3 (523.3%). In addition, OC and sulfate are more sensitive to heat wave events. Our analysis provides improved understanding of the formation of PM 2.5 pollution with respect to meteorology, particularly EUMEs. Based on such information, more attention may be needed on the collaborative prediction of EUMEs and air pollution episodes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)