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Pickled tea is an anaerobically fermented tea common in Thailand, Myanmar and Yunnan minority areas. γ-aminobutyric acid (GABA) is non-protein amino acid with multiple bioactives, which can be easily produced under anaerobic conditions. During the processing of pickled tea, controlling the process parameters is effective for the production of GABA-rich products; however, the precise parameters remain to be clarified. In the present study, the fresh leaves of Camellia sinensis (L.) Kuntze (C. sinensis) 'FudingDabai', C. sinensis 'MabianLv No. 1', C. sinensis 'Wuniuzao' and C. sinensis 'Fuxuan No. 9' were used as raw materials to process GABA-rich pickled tea. Single-factor and orthogonal experiments were conducted to determine the best tea cultivars and optimize the best processing parameters via comparing the content of GABA, tea polyphenols (TPs) and other biochemical components of GABA-rich pickled tea. The results of the signal-factor experiment showed that the fresh leaves of C. sinensis 'MabianLv No. 1' had the highest GABA content of 2.61 mg·g−1 after treatment with vacuum for 6 h; therefore, C. sinensis 'MabianLv No. 1' was selected as the raw material for the subsequent experiments. Orthogonal experiments showed that the highest GABA content of 2.53 mg·g−1 was found in the pickled tea with 8 h of vacuum treatment, 20 min of rolling after microwave fixing, 20 min of spreading and 20 d of anaerobic fermentation at room temperature. Further, the sensory evaluation showed that it possesses a strong sour taste with a slight sweetness and a light yellow color and better comprehensive quality. This indicates that these parameters are optimal for the processing of GABA-rich pickled tea. This study will provide scientific basis for the subsequent production of high GABA tea. [ABSTRACT FROM AUTHOR]

Impatiens uliginosa is a native and potential water body-restoring ornamental plant. In this study, RNA-Seq technology was used to analyze the transcriptome of its floral organs. Candidate genes related to flower color changes under copper stress were investigated through transcriptome screening, and the intrinsic mechanism of the effects of different concentrations of copper on I. uliginosa was revealed at the molecular level. The main findings were as follows: (1) Transcriptome sequencing analysis was performed on the flower organs of I. uliginosa treated with different concentrations of copper (0 mg·L−1, 10 mg·L−1, and 20 mg·L−1). A total of 70,319 transcripts and 39,949 unigenes were obtained. An analysis of differentially expressed genes revealed structural genes including GT, ANS, CHI, and PAL; transcription factors including MYB and WD40; and transport factors including GST and ABC. (2) The gene expression levels of flower color changed in the flowering period of I. uliginosa at different copper concentrations. The expression levels of IuGT and IuGST genes in I. uliginosa were significantly different under different concentrations of copper treatments. Their expression levels were the highest at a copper concentration of 0 mg·L−1 and the lowest at 20 mg·L−1. In summary, the low expression of IuGT and IuGST genes was more conducive to the formation of white flowers of I. uliginosa. [ABSTRACT FROM AUTHOR]

In this paper, we present a sample of 21 repeating fast radio bursts (FRBs) detected by different radio instruments before September 2021. Using the Anderson–Darling test, we compared the distributions of extra-Galactic dispersion measure ( D M E ) of non-repeating FRBs, repeating FRBs and all FRBs. It was found that the D M E values of three sub-samples are log-normally distributed. The D M E of repeaters and non-repeaters were drawn from a different distribution on basis of the Mann–Whitney–Wilcoxon test. In addition, assuming that the non-repeating FRBs identified currently may be potentially repeators, i.e., the repeating FRBs to be universal and representative, one can utilize the averaged fluence of repeating FRBs as an indication from which to derive an apparent intensity distribution function (IDF) with a power-law index of a 1 = 1.10 ± 0.14 ( a 2 = 1.01 ± 0.16 , the observed fluence as a statistical variant), which is in good agreement with the previous IDF of 16 non-repeating FRBs found by Li et al. Based on the above statistics of repeating and non-repeating FRBs, we propose that both types of FRBs may have different cosmological origins, spatial distributions and circum-burst environments. Interestingly, the differential luminosity distributions of repeating and non-repeating FRBs can also be well described by a broken power-law function with the same power-law index of −1.4. [ABSTRACT FROM AUTHOR]