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In order to investigate the effect of inoculated fermentation with different Aspergillus strains on the umami taste of Liuyang Douchi, the differences in the umami taste and protein degradation of Liuyang Douchi fermented naturally (NF) or by four dominant Aspergillus flavus strains isolated from Douchi (A. flavus 7214, A. flavus 7622, A. flavus 6112, and A. flavus 5322) alone and their mixture in an equal proportion (M4) were compared. The results showed that the major protease produced by each of the four strains was serine proteases, and A. flavus 5322 had the strongest protease activity, with significantly higher activity of acidic protease than the other three strains. The contents of amino acid nitrogen and water-soluble protein in Aspergillus fermented Douchi were higher than those in NF Douchi after the end of pile-fermentation stage. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that the degradation trends of six proteins in Douchi were consistent, all of which exhibited rapid degradation during the pile-fermentation process. Additionally, the results of sensory evaluation and electronic tongue analysis showed that Douchi fermented by A. flavus 5322 showed the strongest umami taste, which significantly increased when compared with NF. Using ultra-high performance liquid chromatography-electrospray/quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-Q-TOF-MS/MS) combined with correlation and peptidomics analysis, a total of 43 potential umami peptides were identified. The total peak area of potential umami peptides in Douchi fermented by A. flavus 6112 was the highest, followed by A. flavus 5322 with little difference, significantly greater than that in NF Douchi. In summary, inoculated fermentation, especially with A. flavus 5322, could promote protein degradation and the release of potential umami peptides, thereby enhancing the umami taste of Liuyang Douchi. This study will provide theoretical guidance for improving the umami taste of Liuyang Douchi and development of industrial production strains.

Oligodendrocyte precursor cells (OPCs) have long been regarded as progenitors of oligodendrocytes, yet recent advances have illuminated their multifaceted nature including their emerging immune functions. This review seeks to shed light on the immune functions exhibited by OPCs, spanning from phagocytosis to immune modulation and direct engagement with immune cells across various pathological scenarios. Comprehensive understanding of the immune functions of OPCs alongside their other roles will pave the way for targeted therapies in neurological disorders.

Food safety incidents caused by pesticide residues are threatening the life and health of people. At present, pesticide residues in food samples are miscellaneous, low and unknown to testing personnel and thus difficult to detect. Therefore, it is of great significance to develop high-throughput and non-targeted for the detection of pesticide residues in food samples. Chromatography-mass spectrometry has been widely used in the field of pesticide residue detection because of its advantages of high separation and identification efficiency as well as high-throughput and non-targeted nature. This paper summarizes the literature on high-throughput and non-targeted detection of pesticide residues in food samples by chromatography-mass spectrometry in the past 10 years. The current status of multi-pesticide residue detection in food samples is briefly described. Besides, this paper focuses on the application of chromatography-mass spectrometry in the detection of pesticide residues in food samples from the perspectives of the development of multidimensional chromatography and high-resolution mass spectrometry, the improvement of sorbent materials and sample pretreatment techniques, and the optimization of chemometric algorithms. Some suggestions for the problems existing in this field of research are put forward aiming to provide a new reference for the application of chromatography-mass spectrometry in the detection of multi-pesticide residues in food samples.

The aroma components of two grades of Huangjincha tea 2 were investigated by using headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) to establish their aroma fingerprints. The results were analyzed using chemometrics. Totally 81 aroma components were identified, 41 of which were common to both. Based on these common aroma components, the two grades could be discriminated by orthogonal partial least squares-discrimination analysis (OPLS-DA), and nine differential aroma components between them were identified including heptanal, limonene, trans-β-ocimene, 1-octanol, (E)-4,8-dimethylnona-1,3,7-triene, trans-nerolidol, 1,10-diepicubenol, epicubenol, and methyl hexadecanoate. A linear discriminant model to distinguish the two grades was established using the differential aroma components as independent variables. The self-validation and cross-validation accuracy of this model were 100%. These results may provide an objective and quantitative reference for the classification of Huangjincha 2.

Early postnatal interruption of the bidirectional GABA/TNFSF12 signaling between parvalbumin-positive interneurons and oligodendrocyte precursor cells impairs correct prefrontal cortical network activity and social cognitive behavior later in life.

Measuring motor performance in individuals with intellectual disabilities (ID) is quite challenging. The objective of this study was to compare the motor performances of individuals with ID and those with typical development (TD) during soccer dribbling through video-based behavior-coded movement assessment along with a wearable sensor. A cross-sectional research design was adopted. Adolescents with TD (N = 25) and ID (N = 29) participated in the straight-line and zigzag soccer dribbling tests. The dribbling performance was videotaped, and the footage was then analyzed with customized behavior-coding software. The coded parameters were the time for movement completion, the number of kicks, blocks, steps, the number of times the ball went out of bounds, the number of missed cones, and the trunk tilt angle. Participants with ID exhibited significantly poorer performance and demonstrated greater variances in many time and frequency domain parameters. It also revealed that participants with ID kicked with both feet while dribbling, whereas those with TD mainly used the dominant foot. The present findings demonstrated how the ID population differed from their peers in lower-extremity strategic control. The customized video-based behavior-coded approach provides an efficient and effective way to gather behavioral data and calculate performance parameter statistics in populations with intellectual disabilities. [ABSTRACT FROM AUTHOR]

In this paper, a novel strategy of "pick the best of the best" was proposed for the nondestructive identification of different‐origin and adulterated Poria cocos with near‐infrared spectroscopy. First, various preprocessing methods were divided into three classes: baseline correction, scattering and trend correction, and scaling. The single preprocessing methods with the best predictions in each class were selected. Then, the selected preprocessing methods were combined in pairs according to three classes. The pair combination preprocessing methods with the best predictions and also better predictions than single methods were selected. Finally, the selected pair combination preprocessing method was combined with the methods in the unselected class. The three combination preprocessing methods with the best predictions and also better predictions than pair combination methods were selected as the final prediction. With this strategy, the optimized preprocessing combination can be obtained quickly, and the identification accuracy with principal component analysis method can be greatly improved. 0% identification accuracy of adulterated samples and 12.5% identification accuracy of different‐origin samples were obtained with the raw data. However, 100% accuracy of adulterated samples, 93.8% accuracy of calibration dataset, and 75% accuracy of validation dataset can be obtained with the novel strategy. The developed technology can be regarded as a simple, rapid, and accurate nondestructive identification method for different‐origin and adulterated samples, and has a broad application prospect in the future. [ABSTRACT FROM AUTHOR]