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[Solid-phase extraction coupled with high performance liquid chromatography-triple quadrupole mass spectrometry for simultaneous determination of seven coumarins in water samples from drinking water treatment plants]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 78-86页

作者： wen-Mei Jiao Jing-Ming Yang Ce xu Fu-Kang Gao Lu-Yao Shen Yu-bo Yuan Zhi-Fen Guo Guang Huang School of Life Sciences and Chemical Engineering Jiangsu Second Normal University Nanjing 211200 China. School of Stomatology Nanjing Medical University Nanjing 210029 China. School of Public Health Nanjing Medical University Nanjing 211166 China. Key Laboratory of Modern Toxicology Ministry of Education School of Public Health Nanjing Medical University Nanjing 211166 China.

Chlorinated coumarins, which are as cytotoxic as highly toxic halobenzoquinones toward CHO-K1 cells, have recently been identified as disinfection byproducts in drinking water disinfection processes. Therefore, detecting coumarins in water samples collected at various stages from drinking water treatment plants helps assess the formation of chlorinated coumarins in drinking water. Hence, a simple, rapid, accurate, and sensitive method for quantifying coumarins in water samples is required. In this study, a method was developed based on solid-phase extraction coupled with high performance liquid chromatography-triple-quadrupole mass spectrometry for analyzing seven coumarins in water samples from drinking water treatment plants, including 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, 8-chloro-7-hydroxycoumarin, coumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin. Sample pretreatment involved solid-phase extraction using HLB columns, followed by elution with water and methanol, each containing 0.25% formic acid. The extracted solution was separated via gradient elution using a Phenomenex Luna C18 column (100 mm×2.0 mm, 3 mm) with 0.1% formic acid aqueous solution and methanol as the mobile phases, with analytes detected by triple-quadrupole mass spectrometry equipped with electrospray ionization source in multiple reaction monitoring mode. The matrix effect, precision, and accuracy of the developed method were investigated using raw and treated water as matrices. Matrix effects of 0.84-1.12 were recorded for the detection of 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, and coumarin in raw water, while values of 0.67-0.70 were recorded for 8-chloro-7-hydroxycoumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin in finished water. The three chlorinated coumarins exhibited matrix effects above 0.80 after the finished water matrix had been diluted four times. These re

关键词： coumarins disinfection byproducts drinking water high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) solid-phase extraction (SPE)

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Mechanism of action of Linggui Zhugan Decoction in treating non-alcoholic fatty liver disease using untargeted metabolomics approach

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Traditional Medicine Research 2025年第2期10卷 65-76页

作者： Huan Pei Ren-Lin Li Xin-Ran Song Qian-Qian Wan Yu-Ming Wang Han-Zhou Li Wei-Quan xu Jia-Bao Liao Wei-bo wen Jing Miao Huan-Tian Cui School of Basic Medicine Yunnan University of Chinese MedicineKunming 650599China School Clinical Medical College Yunnan University of Chinese MedicineKunming 650599China First School of Clinical Medicine Yunnan University of Chinese MedicineKunming 650599China School of Integrative Chinese and Western Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Pharmacy Tianjin Second People's HospitalTianjin 300192China

Background:Non-alcoholic fatty liver disease(NAFLD)is a liver disorder characterized by the accumulation and degeneration of fat in the liver cells,a condition that may further deteriorate and lead to cirrhosis and liver *** studies showed that metabolic dysfunction can promote NAFLD *** Zhugan Decoction(LGZGD)has therapeutic effects on *** mechanism of LGZGD still remains *** study was to examine the impact of LGZGD on the metabolic processes involved in the development of ***:A mice model of NAFLD was treated with *** therapeutic potential of LGZGD was evaluated by assessing the activity of transaminases,lipids levels of blood,and pathological changes in the liver of the mice model of ***,this study also evaluated the influence of LGZGD on liver inflammation and oxidative ***:The results of untargeted metabolomics analysis showed that LGZGD reduced the disordered lipid metabolism in NAFLD *** improved the oxidative stress and also reduced the levels of pro-inflammatory cytokines in the *** metabolomics analysis of liver samples revealed that LGZGD treatment improved metabolic disorders,including alanine,aspartate,glutamate,glycerophospholipid metabolism,and citrate *** RT-qPCR and Western blot results showed that LGZGD could regulate the expression of key enzymes in the metabolic pathway of the citrate cycle,including ATP-citrate lyase(ACLY),alanine-glyoxylate aminotransferase-2(AGXT2),phosphatidylethanolamine N-methyltransferase(PEMT),and succinate dehydrogenase(SDH).Conclusion:We found that LGZGD can treat NAFLD by reducing inflammatory responses,inhibiting oxidative stress,regulating alanine,aspartate,glutamate,and glycerophospholipid metabolism,and citrate cycle pathways.

关键词： NAFLD LGZGD untargeted metabolomics glycerophospholipid metabolism citrate cycle

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Visualization of the protective role of estrogen against female liver fibrosis via an ER viscosity NIR fluorescent probe

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Science China Chemistry 2025年第1期 360-368页

作者： Zheng Liu Changyu Zhang Zipeng Li Wanying Ma Jia Liu Xiang Xia Ning xu wen Sun Jianjun Du Jiangli Fan Xiaojun Peng State Key Laboratory of Fine Chemicals Dalian University of Technology Ningbo Institute of Dalian University of Technology

Endoplasmic reticulum(ER) viscosity has emerged as a new potential biomarker for hepatic fibrosis(HF). Herein, we report the first ER-targeting viscosity-responsive near-infrared(NIR) fluorescent probe HBT-PP for investigations of HF *** twisted intramolecular charge transfer(TICT) and the excited state intramolecular proton transfer(ESIPT) are combined to endow HBT-PP with the selective response towards viscosity(～62-fold) and a super large stokes shift(～320 nm). HBT-PP mainly targets organelle ER and is able to image the drug-or alcohol-induced viscosity elevation in living cells. Significantly,HBT-PP was successfully applied to visualize the gender difference in HF and the protective role of estrogen in restraining HF progression. Of note, after 10 min of stain with HBT-PP, HF lesions showed a stage-based response, indicating the potential of this probe in fast and early diagnosis of HF. These results clearly demonstrated the promising application of HBT-PP as a new tool for exploring ER viscosity-involved physiological and pathological processes.

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Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期 308-316页

作者： Sili Wang Jiancheng Huang Yanan Du Wei Huang Yufeng xue Xiaokun xu Guannan Zhong Yuanyuan Shi Bin Hong Xiaoying Bian wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

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消费者估值不确定下众筹定价策略及退款机制研究

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管理工程学报 2025年第1期39卷 256-270页

作者：徐扬毕功兵宋文吴娟安徽财经大学金融学院中国科学技术大学管理学院南京审计大学金融学院

众筹作为最受欢迎的互联网金融产品之一,受到工业界和学术界的广泛关注。基于现实背景,本文建立了两阶段众筹模型,研究了消费者估值不确定下消费者的策略性选择行为及其对众筹定价策略的影响。结论表明,若消费者参与众筹的额外效用较低... 详细信息

众筹作为最受欢迎的互联网金融产品之一,受到工业界和学术界的广泛关注。基于现实背景,本文建立了两阶段众筹模型,研究了消费者估值不确定下消费者的策略性选择行为及其对众筹定价策略的影响。结论表明,若消费者参与众筹的额外效用较低,消费者估值不确定会造成“搭便车”现象,导致最优众筹价格不是关于项目所需资金的单增函数。当项目所需资金较低或较高时,发起人应该设置较高的众筹价格,否则应该降低价格以激励更多的消费者参与众筹。通过对比传统销售模式,本文揭示了发起人可以利用消费者估值不确定性及众筹的预售机制增加销量或边际收益以提升利润。进一步,本文证明了退款机制可以有效增加消费者参与众筹的意愿,从而提高众筹的可行域。最后,本文将基本模型拓展到更加一般的情形,研究发现众筹市场大小、项目运作风险和生产能力均对最优定价决策有不可忽视的影响。

关键词：众筹定价决策估值不确定策略型消费者退款机制

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新型级配图的分析与验证

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同济大学学报（自然科学版） 2002年第3期30卷 307-311页

作者：刘红聂文波许志鸿陈兴伟同济大学道路与交通工程系上海200092 吉林省公路工程局监理公司吉林长春130012

通过马氏试验结果 ,验证了碎石矿质混合料级配最大密度时 ,实验指数为 0 .4 5的合理性 .同时对级配曲线半对数坐标、常数坐标、幂指数坐标三种形式的优缺点进行了详细分析 ,从理论上论述了幂指数坐标是级配曲线的最佳坐标形式 .最后用... 详细信息

通过马氏试验结果 ,验证了碎石矿质混合料级配最大密度时 ,实验指数为 0 .4 5的合理性 .同时对级配曲线半对数坐标、常数坐标、幂指数坐标三种形式的优缺点进行了详细分析 ,从理论上论述了幂指数坐标是级配曲线的最佳坐标形式 .最后用球体理论、干涉理论对实验指数为 0 .4 5时。

关键词：最大理论密度级配曲线球体理论路面材料矿质混合料组成设计级配图沥青混合料

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预测反褶积用于消除深海鸣震的一种新途径

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石油物探 1980年第4期 5-18页

作者：许文源徐伯勋王怀恩姜成栋

过去,在处理深海域的地震资料时,一般是采用“反向消去法”或“深水波形预测反褶积法”来消除鸣震。但是,当鸣震和反射波互相干涉时,这些方法的效果不理想。为了改善这类资料的处理效果,本文提出一种新的“深海预测反褶积法”。与上述... 详细信息

过去,在处理深海域的地震资料时,一般是采用“反向消去法”或“深水波形预测反褶积法”来消除鸣震。但是,当鸣震和反射波互相干涉时,这些方法的效果不理想。为了改善这类资料的处理效果,本文提出一种新的“深海预测反褶积法”。与上述两种方法比较,这种方法所要求的前提条件少,应用的范围更广泛。理论分析和模型试验的结果表明,这种方法的效果是令人满意的。

关键词：鸣震反射波并合数反射层地层时窗深海

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Fuzzy Q-learning in continuous state and action space

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 100-109页

作者： xu Ming-liang xu wen-bo Department of Electronic Information Engineering Wuxi City College of Vocational Technology Wuxi 214063 China School of Information Technology Jiangnan University Wuxi 214122 China

An adaptive fuzzy Q-leaming （AFQL） based on fuzzy inference systems （FIS） is proposed. The FIS realized by a normalized radial basis function （NRBF） neural network is used to approach Q-value function, whose input is composed of state and action. The rules of FIS are created incrementally according to the novelty of each element of the pair of state-action. Moreover the premise part and consequent part of the FIS are updated using extended Kalman filter （EKF）. The action that impacts on environment is the one with maximum output of FIS in the current state and generated through optimization method. Simulation results in the wall-following task of mobile robots and the inverted pendulum balancing problem demonstrate that the superiority and applicability of the proposed AFQL method.

关键词： Q-learning FIS continuous adaptation

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黑米花青素的醇提工艺优化

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食品工业科技 2018年第21期39卷 172-177页

作者：龙跃腾向珣朝颜李梅杨博文许亮游慧西南科技大学植物分子遗传育种实验室四川绵阳621010

为了提高无水乙醇提取黑米花青素的得率,先通过单因素实验研究乙醇体积分数、提取时间、料液比、温度和提取液pH对黑米花青素提取的影响,再通过正交试验确定黑米花青素提取的最佳工艺条件。结果表明:提取液pH对黑米花青素的提取影响最大... 详细信息

为了提高无水乙醇提取黑米花青素的得率,先通过单因素实验研究乙醇体积分数、提取时间、料液比、温度和提取液pH对黑米花青素提取的影响,再通过正交试验确定黑米花青素提取的最佳工艺条件。结果表明:提取液pH对黑米花青素的提取影响最大,提取时间次之。最佳提取条件是乙醇体积分数为80%,提取时间为60 min,提取温度为45℃,料液比为1∶7 (g∶mL),提取液pH为1;采用该优化工艺,黑米首次提取液的花青素含量可达34.34μg/mL。最佳提取次数为3次,其花青素相对总提取率达到99.29%,得率为298.23μg/g。该优化工艺将为黑稻资源的花青素商业化开发提供技术支撑,为黑米花青素的产业化发展提供有益参考。

关键词：黑米花青素提取工艺优化乙醇

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Lenalidomide regulates the CCL21/CCR7/ERK1/2 axis to inhibit migration and proliferation in diffuse large B-cell lymphoma

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Oncology research 2025年第1期33卷 199-212页

作者： wen Yang Bin Tang Dan xu wenxiu Yang Department of Pathology Guizhou Medical University The Affiliated Hospital of Guizhou Medical University Guiyang 550004 China.

Background:The prognostic significance of the chemokine receptor CCR7 in diffuse large B-cell lymphoma (DLBCL) has been reported previously. However, the detailed mechanisms of CCR7 in DLBCL, particularly regarding its interaction with lenalidomide treatment, are not fully understood.Methods:Our study utilized bioinformatics approaches to identify hub genes in SU-DHL-2 cell lines treated with lenalidomide compared to control groups. Immunohistochemical data and clinical information from 122 patients with DLBCL were analyzed to assess the correlation of CCR7 and p-ERK1/2 expression with the prognosis of DLBCL. Furthermore, and experiments were conducted to clarify the role of CCR7 in the response of DLBCL to lenalidomide treatment.Results:Our bioinformatics analysis pinpointed CCR7 as a hub gene in the context of lenalidomide treatment in DLBCL. Notably, 31.14% and 36.0% (44/122) of DLBCL cases showed positive expression for CCR7 and ERK1/2 respectively, establishing them as independent prognostic factors for adverse outcomes in DLBCL via multivariate Cox regression analysis. Additionally, our studies demonstrated that the external application of the protein CCL21 promoted proliferation, migration, invasion, and activation of the ERK1/2 pathway in SU-DHL-2 and OCI-LY3 cell lines with high levels of CCR7 expression. This effect was mitigated by CCR7 silencing through siRNA, application of ERK inhibitors, or lenalidomide treatment. experiments reinforced the efficacy of lenalidomide, significantly reducing tumor growth rate, tumor mass, serum total LDH levels, and expression of CCR7 and p-ERK1/2 in a SU-DHL-2 xenograft model in nude mice ( < 0.05).Conclusion:Our study clarifies the potential role of the CCL21/CCR7/ERK1/2 axis in the therapeutic effects of lenalidomide in DLBCL treatment.

关键词： CCL21 CCR7 Diffuse large B-cell lymphoma (DLBCL) ERK1/2 Lenalidomide

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