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In order to clarify the influence of Lactiplantibacillus pentosus fermentation on the structure of peanut proteins, changes in the structure of peanut protein isolate (PPI), arachin and conarachin before and after fermentation were studied. The results showed that L. pentosus fermentation significantly increased the free sulfhydryl content, surface hydrophobicity and denaturation temperature, and significantly reduced the β-folding content and denaturation enthalpy of arachin (P < 0.05). It reduced the free sulfhydryl content, surface hydrophobicity, and denaturation enthalpy, and significantly increased the degeneration temperature and α-helix content of PPI and conarachin (P < 0.05). Through particle size, potential and spectral analysis, we found that L. pentosus fermentation significantly improved the particle size and zeta potential of each protein component, and resulted in a red shift in their fluorescence peaks. In contrast to PPI and conarachin, the maximum fluorescence emission wavelength of arachin showed a 1.3 and 2.4 nm red shift, and arachin exhibited a 19.54% and 14.75% higher increase in thermal denaturation temperature, respectively. Thermal properties and scanning electron microscopic (SEM) analysis showed that arachin had maximum structural unfolding and higher thermostability after fermentation, indicating that L. pentosus fermentation is more likely to promote the molecular modification of arachin, and contributes to the gel modification of peanut proteins.

Fu brick tea (FBT) is a unique compressed dark tea in China. The unique fungal fermentation process creates its unique fungal flavor and special health benefits, so FBT is deeply favored by consumers. This paper reviews the research results on the volatile components contributing to the aroma of FBT and the methods for their evaluation. The reported volatile compounds are systematically classified, and the compounds with high detection frequency are elaborated in detail. The methods for the extraction, qualitative and quantitative analysis of the volatile compounds and the methods for the screening and evaluation of the odor-active compounds of FBT are summarized. Meanwhile, the problems with the current studies and the focus of future research are pointed out.

[Purpose/Significance] This paper aims at discussing the current situation and characteristics of the scientific and technical novelty search evaluation, and putting forward suggestions for the research. [Method/Process] We analyze the research status and problems of the domestic scientific and technical novelty search evaluation from the aspects of evaluation subject and object, evaluation index system, evaluation methods, and empirical research through the literature content analysis method. [Results/Conclusions] It is found that there are some problems in the evaluation of scientific and technical novelty search in China, such as fuzzy and confused evaluation objects, a lack of quantitative evaluation indicator system and standard, , neglect of evaluation of the service efficiency, and a lack of discussion of the development of scientific and technical search after evaluation. Finally, some suggestions for future research are put forward, such as clarifying the evaluation object and its concept boundary, designing the top-level index system guided by efficiency, implementing the internal and external dual evaluation mechanism, and meeting the needs and focusing on detailed development.

Background and purpose: The expression of programmed death ligand-1 (PD-L1) in lung cancer not only is the most important biomarker for predicting the efficacy of programmed death-1 (PD-1)/PD-L1 inhibitors, but also may affect the efficacy of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) targeted therapy. However, there are currently few reports in the relevant literature on whether the expression of PD-L1 in lung cancer can affect the efficacy of chemotherapy in patients with lung adenocarcinoma. This study mainly explored the effect of PD-L1 expression in lung adenocarcinoma on the efficacy of pemetrexed-based chemotherapy and its underlying mechanism. Methods: From Oct. 2015 to Dec. 2018, 185 eligible lung adenocarcinoma patients treated in Department of Pathology, The General Hospital of Western Theater Command PLA were enrolled. The expressions of PD-L1 and thymidylate synthase (TS), a molecule predicting the efficacy of pemetrexed-based chemotherapy, were detected by immunohistochemistry. The survival curve of patients was drawn by Kaplan-Meier method. The log-rank test and COX regression model were used to analyze the clinicopathological factors affecting the patients’ progression-free survival (PFS) and overall survival (OS). The log-rank test was used to analyze the effects of PD-L1 and TS expressions on the patients’ PFS and OS. Spearman rank correlation test was used to analyze the correlation between PD-L1 expression and TS expression in lung cancer tissues. Western blot and real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR) were used to detect the protein and mRNA expressions of PD-L1 and TS in 6 types of lung adenocarcinoma cell lines. The Pearson correlation test was used to analyze the correlation between PD-L1 and TS at protein expression level and mRNA expression level. Results: Among 51 patients with advanced lung adenocarcinoma who received pemetrexed-based chemotherapy as first-line treatment, the objective response rate (ORR) of the PD-L1 positive group was 20.0%, and the disease control rate (DCR) was 60.0%. There was no significant difference compared with the PD-L1 negative group (ORR: 20.0% vs 35.5%, χ 2 =1.404, P=0.236; DCR: 60.0% vs 80.6%, χ 2 =2.602, P=0.107). The median PFS (mPFS) of patients with negative expression of PD-L1 was significantly better than that of patients with positive expression of PD-L1 (mPFS: 5.6 months vs 4.1 months, log-rank=5.406, P=0.020), and there was no significant difference in median OS (mOS) between them (mOS: 15.9 months vs 12.7 months, log-rank=0.525, P=0.469). Univariate analysis found that the positive expressions of PD-L1 and TS were risk factors for PFS ［PD-L1 negative vs positive: HR=2.002 (1.100-3.645), P=0.023; TS negative vs positive: HR=2.205 (1.367-4.587), P=0.003］. Multivariate analysis found that TS positive expression was an independent risk factor for PFS ［TS negative vs positive: HR=3.245 (1.091-9.652), P=0.034］. Among the 51 patients with advanced lung adenocarcinoma who received pemetrexed-based chemotherapy as the first-line treatment, the expression of PD-L1 in cancer tissues was significantly positively correlated with the expression of TS (r s =0.691, P