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To study the difference in the contents of phenolics and the antioxidant activities between two kinds of Hawk tea of different maturity levels, and to evaluate their qualities, the contents of 15 phenolic compounds were determined using LC-MS/MS method. Then, the antioxidant activities of two types of tea were evaluated using DPPH radical scavenging rate, ABTS+ radical scavenging rate, and Fe3+ ferric reducing antioxidant power (FRAP). And then, the contents of 15 phenolic compounds and the antioxidant activities between two kinds of Hawk tea of different maturity levels were analyzed by analysis of variance (ANOVA). Based on the contents of 15 phenolic compounds, hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least square-discriminant analysis (OPLS-DA) were used to classify two kinds of Hawk tea. Finally, the contribution of different phenolic compounds in Hawk tea to antioxidation was discussed by partial least square regression analysis (PLSR). The results were as follows: (1) The contents of catechin, p-coumaric acid, isoquercitrin, hyperoside, nicotiflorin, astragalin, kaempferol, quercetin, and afzelin in tender leaf tea were significantly higher than those in old leaf tea, among which the average contents of catechin, isoquercitrin, and astragalin were higher than those in old leaf tea by 1 039.43, 169.12 and 257.35 mg·100 g-1, respectively. The results of HCA, PCA, and OPLS-DA could distinguish two kinds of Hawk tea. (2) The ANOVA showed significant differences in DPPH radical scavenging rate, ABTS+ radical scavenging rate, and FRAP between two kinds of tea, with the tender leaf tea superior to the old leaf tea. (3) The PLSR suggested that isoquercitrin, catechin, astragalin, chlorogenic acid, hyperoside, p-coumaric acid, and kaempferol were the main phenolic compounds those contributed to the antioxidant activity of Hawk tea. This study can provide a reference for Hawk tea's quality control and application promotion.

This study focuses on four traditional earthen–wooden villages in Hunan Province, exploring the multifaceted impacts of tourism development on the quality of life from the perspectives of both residents and tourists. Utilizing structural equation modeling, this research examines how macro-level cultural resources, meso-level spatial characteristics, and micro-level traditional architecture influence the development of cultural tourism and its subsequent effects on quality of life. The findings indicate that while cultural resources and spatial characteristics positively contribute to the quality of cultural tourism development, traditional architecture presents a complex challenge. Specifically, traditional architecture negatively impacts quality of life due to maintenance demands and modernization pressures, yet it also enhances cultural tourism through its intrinsic heritage value. Spatial characteristics are identified as the most significant positive factor, indirectly enhancing both tourism quality and overall life satisfaction by enriching the cultural landscape. Additionally, the study uncovers significant differences in how residents and tourists perceive the impacts of tourism. Tourists generally seek enriching and authentic experiences, while residents are more directly affected by the socio-economic and environmental changes brought by tourism. This divergence highlights the need for balanced and targeted management strategies that address the distinct needs and perceptions of both groups at various stages of tourism development. By addressing these dynamic factors, this study offers valuable insights for policymakers and administrators aiming to balance heritage preservation with sustainable economic growth in traditional earthen–wooden villages. The research also underscores the critical role of community engagement and adaptive strategies in fostering resilient and thriving rural communities in the 21st century. [ABSTRACT FROM AUTHOR]

Objective To investigate the association between RET genotype and disease phenotype in the patients with hereditary medullary thyroid carcinoma (HMTC). Methods A total of 13 patients diagnosed as HMTC and undergoing surgical treatment for thyroid carcinoma in this hospital from March 2015 to September 2019 were analyzed retrospectively with follow-up cutoff at September 2021. The patient risk stratification was performed according to American Thyroid Association (ATA) guidelines. The association between RET genotype and disease phenotype including biochemical results, TNM stage, both biochemical [normal serum calcitonin(CT)] cure and clinical cure was analyzed. Results There were 1 (7.69%) case, 6(46.15%) cases, and 6(46.15%) cases with the highest risk mutation (RET M918T), high-risk mutation (RET C634Y and C634S), and moderate-risk mutation (RET C618G and C611Y), respectively. One case with the highest risk mutation was at TNM stage Ⅳ. There were 4 cases (66.67%) at stageⅠand 2 cases (33.33%) at stage Ⅲ among 6 cases with high-risk mutation. For 6 cases with moderate-risk mutation, stage Ⅰ and stage Ⅱ had 1 case(16.67%) respectively, and stage Ⅲ and stage Ⅳ with 3 cases (50%) and 1 case (16.67%) respectively. The highest preoperative CT and carcinoembryonic antigen were detected in 1 case with highest risk mutations (20 000 ng/L, 831.8 μg/L), and those lower in 6 cases with moderate-risk mutations (1 221.4 ng/L, 62.3 μg/L). The lowest of them were in 6 cases with high-risk mutations (537.7 ng/L, 41.7 μg/L). Similarly, both clinical cure rate and biochemical cure rate were found poorer in the cases with the highest risk mutation, and better in the case with high-risk mutation, and less better in the cases with moderate-risk mutation. Conclusions RET gene could be associated with HMTC risk of ATA. The patients of RET genotype with high-risk mutations would have higher clinical cure rate and biochemical cure rate than the cases with moderate-risk mutations.

Nonphotochemical quenching mechanisms regulate light harvesting in oxygenic photosynthesis. Measurement techniques for nonphotochemical quenching have typically focused on downstream effects of quenching, such as measuring reduced chlorophyll fluorescence. Here, to directly measure a species involved in quenching, we report snapshot transient absorption (TA) spectroscopy, which rapidly tracks carotenoid radical cation signals as samples acclimate to excess light. The formation of zeaxanthin radical cations, which is possible evidence of zeaxanthin-chlorophyll charge-transfer (CT) quenching, was investigated in spinach thylakoids. Together with fluorescence lifetime snapshot data and time-resolved high-performance liquid chromatography (HPLC) measurements, snapshot TA reveals that Zea•+ formation is closely related to energy-dependent quenching (qE) in nonphotochemical quenching. Quantitative and dynamic information on CT quenching discussed in this work give insight into the design principles of photoprotection in natural photosynthesis.

In this work, the antioxidant components in persimmon (Diospyros kaki) leaves were separated by offline two‐dimensional liquid chromatography‐electrochemical detection (LC×LC‐ECD) and identified by LC‐tandem mass spectrometry (LC‐MS/MS). A total of 33 antioxidants, mainly proanthocyanidins, and glycosides of kaempferol and quercetin, were identified. The antioxidant assays demonstrated that the fractions collected from the first‐dimension LC (1D‐LC) possessed considerable radical scavenging capabilities, with correlation coefficients of peak area versus radical scavenging capability of 1,1‐diphenyl‐2‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) being 0.9335 and 0.9116, respectively. The fingerprinting showed that 37 peaks were present in all samples. The major antioxidant components of persimmon leaves were the glycosides of kaempferol and quercetin. Finally, fourteen antioxidants were quantitatively assessed. Offline LC×LC provided high peak capacity and separation; ECD enabled specific screening and detection of antioxidant components; and MS/MS provided excellent identification capability. In this study, the combination of the three approaches was utilized to screen for antioxidant components in persimmon leaves, with satisfactory findings. In conclusion, this technique is an effective means for rapid analysis of antioxidant components and quality control of medicinal plants, achieving rapid separation of congeners and facilitating more accurate qualitative and quantitative analyses. [ABSTRACT FROM AUTHOR]

Plants, algae and cyanobacteria need to regulate photosynthetic light harvesting in response to the constantly changing light environment. Rapid adjustments are required to maintain fitness because of a trade-off between efficient solar energy conversion and photoprotection. The xanthophyll cycle, in which the carotenoid pigment violaxanthin is reversibly converted into zeaxanthin, is ubiquitous among green algae and plants and is necessary for the regulation of light harvesting, protection from oxidative stress and adaptation to different light conditions(1,2). Violaxanthin de-epoxidase (VDE) is the key enzyme responsible for zeaxanthin synthesis from violaxanthin under excess light. Here we show that the Chlorophycean VDE (CVDE) gene from the model green alga Chlamydomonas reinhardtii encodes an atypical VDE. This protein is not homologous to the VDE found in plants and is instead related to a lycopene cyclase from photosynthetic bacteria(3). Unlike the plant-type VDE that is located in the thylakoid lumen, the Chlamydomonas CVDE protein is located on the stromal side of the thylakoid membrane. Phylogenetic analysis suggests that CVDE evolved from an ancient de-epoxidase that was present in the common ancestor of green algae and plants, providing evidence of unexpected diversity in photoprotection in the green lineage.

Summary: The coronavirus disease 2019 (COVID‐19) pandemic has a significant impact on the immune system. This is the first and largest study on pre‐existing immune thrombocytopenia (ITP) patients infected with COVID‐19 in China. We prospectively collected ITP patients infected with COVID‐19 enrolled in the National Longitudinal Cohort of Hematological Diseases (NICHE, NCT04645199) and followed up for at least 1 month after infection. One thousand and one hundred forty‐eight pre‐existing ITP patients were included. Two hundred and twelve (18.5%) patients showed a decrease in the platelet (PLT) count after infection. Forty‐seven (4.1%) patients were diagnosed with pneumonia. Risk factors for a decrease in the PLT count included baseline PLT count <50 × 109/L (OR, 1.76; 95% CI, 1.25–2.46; p = 0.001), maintenance therapy including thrombopoietin receptor agonists (TPO‐RAs) (OR, 2.27; 95% CI, 1.60–3.21; p < 0.001) and previous splenectomy (OR, 1.98; 95% CI, 1.09–3.61; p = 0.03). Risk factors for pneumonia included age ≥40 years (OR, 2.45; 95% CI, 1.12–5.33; p = 0.02), ≥2 comorbidities (OR, 3.47; 95% CI, 1.63–7.64; p = 0.001), maintenance therapy including TPO‐RAs (OR, 2.14; 95% CI, 1.17–3.91; p = 0.01) and immunosuppressants (OR, 3.05; 95% CI, 1.17–7.91; p = 0.02). In this cohort study, we described the characteristics of pre‐existing ITP patients infected with COVID‐19 and identified several factors associated with poor outcomes. [ABSTRACT FROM AUTHOR]