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Two types of coumarins-specific enzymes complete the last missing steps in pyran- and furanocoumarins biosynthesis

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Acta Pharmaceutica Sinica B 2024年第2期14卷 869-880页

作者： yucheng zhao Yuedong He Liangliang Han Libo Zhang Yuanzheng Xia Fucheng Yin Xiaobing Wang Deqing zhao Sheng Xu Fei Qiao Yibei Xiao Lingyi Kong Department of Resources Science of Traditional Chinese Medicines School of Traditional Chinese Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China College of Bioscience and Biotechnology Hunan Agricultural UniversityChangsha 410128China Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines Department of Natural Medicinal ChemistryChina Pharmaceutical UniversityNanjing 210009China Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China Ministry of AgricultureTropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural SciencesHaikou 517317China Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China Department of Pharmacology School of Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China

Pyran-and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans,respectively,exhibiting diverse physiological and medical ***,the biosynthetic mechanisms for their core structures remain poorly *** we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring biosynthesis in *** included three distinct *** prenyltransferases(PpPT1e3)responsible for the prenylation of the simple coumarin skeleton 7 into linear or angular precursors,and two novel CYP450 cyclases(PpDC and PpOC)crucial for the cyclization of the linear/angular precursors into either tetrahydropyran or tetrahydrofuran *** analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring *** possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific *** identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic *** study provides new enzymatic tools in the epoxide formation/epoxide-opening mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

关键词： Tetrahydropyrans Tetrahydrofurans Baldwin rules Coumarins CYP450cyclase

The chromosome-scale assembly of the Notopterygium incisum genome provides insight into the structural diversity of coumarins

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3760-3773页

作者： Qien Li Yiqun Dai Xin-Cheng Huang Lanlan Sun Kaixuan Wang Xiao Guo Dingqiao Xu Digao Wan Latai An Zixuan Wang Huanying Tang Qi Qi Huihui Zeng Minjian Qin Jia-Yu Xue yucheng zhao Tibetan Medicine Research Center of Qinghai University Tibetan Medical CollegeQinghai UniversityXining 810016China School of Pharmacy Bengbu Medical UniversityBengbu 233030China Department of Resources Science of Traditional Chinese Medicines School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 210009China College of Horticulture Bioinformatics CenterAcademy for Advanced Interdisciplinary StudiesNanjing Agricultural UniversityNanjing 210095China Key Laboratory of Shaanxi Administration of Traditional Chinese Medicine for TCM Compatibility Shaanxi University of Chinese MedicineXi’an 712046China

Coumarins,derived from the phenylpropanoid pathway,represent one of the primary metabolites found in *** alignment of the tetrahydropyran(THP)and tetrahydrofuran(THF)rings with the lactone structure results in the formation of at least four types of complex ***,the mechanisms underlying the structural diversity of coumarin remain poorly ***,we report the chromosome-level genome assembly of Notopterygium incisum,spanning 1.64 Gb,with a contig N50 value of 22.7 Mb and 60,021 annotated protein-coding ***,we identified the key enzymes responsible for shaping the structural diversity of coumarins,including two p-coumaroyl CoA 2′-hydroxylases crucial for simple coumarins basic skeleton architecture,two UbiA prenyltransferases responsible for angular or linear coumarins biosynthesis,and five CYP736 cyclases involved in THP and THF ring ***,two bifunctional enzymes capable of catalyzing both demethylsuberosin and osthenol were identified for the first *** analysis implies that tandem and ectopic duplications of the CYP736 subfamily,specifically arising in the Apiaceae,contributed to the structural diversity of coumarins in ***,this study proposes a parallel evolution scenario for the complex coumarin biosynthetic pathway among different angiosperms and provides essential synthetic biology elements for the heterologous industrial production of coumarins.

关键词： Notopterygium incisum Parallel evolution Biosynthesis Pyranocoumarins Furanocoumarins

老年功能性便秘采用理气通腑汤与腹针配合治疗对其焦虑抑郁情绪的改善效果

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反射疗法与康复医学 2024年第8期5卷 9-13,29页

作者：赵玉成山东省德州市陵城区中医院中医内科山东德州253500

目的研究老年功能性便秘采用理气通腑汤与腹针配合治疗对其焦虑抑郁情绪的改善效果。方法选取该院2021年10月—2022年10月收治的90例老年功能性便秘患者为研究对象。根据双色球法将其随机分为对照组和观察组。对照组(n=45)采用常规西医... 详细信息

目的研究老年功能性便秘采用理气通腑汤与腹针配合治疗对其焦虑抑郁情绪的改善效果。方法选取该院2021年10月—2022年10月收治的90例老年功能性便秘患者为研究对象。根据双色球法将其随机分为对照组和观察组。对照组(n=45)采用常规西医治疗,观察组(n=45)在对照组基础上加用理气通腑汤联合腹针治疗。比较两组的症状体征积分、直肠感觉功能、直肠肛门测压结果、血清学相关指标、临床疗效、治疗安全性、慢性便秘患者报告临床结局(CC-PRO)量表评分。结果入组时,两组的症状体征积分各方面评分、直肠感觉阈值、排便感觉阈值与最大耐受量比较,组间差异无统计学意义(P>0.05);治疗后,观察组的症状体征积分各方面评分、直肠感觉阈值、排便感觉阈值与最大耐受量均低于对照组,组间差异有统计学意义(P0.05);治疗后,观察组的直肠收缩压、肛门残余压与VIP、5-HT水平分别为(40.18±8.06)mmHg(1 mmHg=0.133 kPa)、(48.92±8.11)mmHg、(13.92±2.24)ng/L、(212.40±17.16)ng/L,均低于对照组的(51.34±10.20)mmHg、(64.50±10.61)mmHg、(17.36±3.02)ng/L、(251.26±20.30)ng/L,MTL、GAS、SP水平与治疗总有效率分别为(193.48±30.45)ng/L、(43.40±7.12)ng/L、(36.50±5.28)ng/L、95.56%,均高于对照组的(159.62±25.37)ng/L、(36.69±6.28)ng/L、(31.66±4.19)ng/L、80.00%,组间差异有统计学意义(P0.05);入组时,两组的CC-PRO各维度评分比较,组间差异无统计学意义(P>0.05);治疗后,观察组的CC-PRO各维度评分均高于对照组,组间差异有统计学意义(P<0.05)。结论在老年功能性便秘患者的治疗中应用理气通腑汤联合腹针的方案安全有效,且有助于改善患者的临床症状、直肠感觉功能,可对胃肠神经递质进行调节,提升其生活质量。

关键词：老年功能性便秘理气通腑汤腹针焦虑抑郁

M0S2/C0S2 composites composed of CoS2 octahedrons and MoS2 nano-flowers for supercapacitor electrode materials

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Frontiers of Materials Science 2018年第4期12卷 354-360页

作者： Haiyan LI yucheng zhao Chang-An WANG State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

In pursuing excellent supercapacitor electrodes, we designed a series of MoS2/CoS2 composites consisting of flower-liked MoS2 and octahedron-shaped CoS2 through a facile one-step hydrothermal method and investigated the electrochemical performance of the samples with various hydrothermal time. Due to the coupling of two metal species and a big amount of well-developed CoS2 and MoS2, the results indicated that the MoS2/CoS2 composites electrodes exhibited the best electrochemical performance with a large specific capacitance of 490 F/g at 2 mV/s or 400 F/g at 10 A/g among all samples as the hydrothermal time reached 48 h (MCS48). Furthermore, the retention of MCS48 is 93.1% after 10000 cycles at 10 A/g, which manifests the excellent cycling stability. The outstanding electrochemical performance of MCS48 indicates that it could be a very promising and novel energy storage material for supercapacitors in the future.

关键词： MoS 2 /CoS 2 composites hydrothermal time electrochemical properties supercapacitors

SLM成形Ti-6Al-4V层状混合点阵结构的力学性能和吸能特性研究

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重庆交通大学学报（自然科学版） 2024年第6期43卷 118-126页

作者：任毅冉威蒲林蔡锶杨赵宇成重庆交通大学航空学院重庆400074 绿色航空能源动力重庆市重点实验室重庆401130

以选区激光熔化(SLM)成形的Ti-6Al-4V钛合金层状混合点阵结构为研究对象。首先设计并制备了由体心立方(BCC)单胞构成的单一点阵结构以及由BCC单胞和面心立方(FCC)单胞组成的2种层状混合点阵结构;其次,利用扫描电子显微镜(SEM)对所制备... 详细信息

以选区激光熔化(SLM)成形的Ti-6Al-4V钛合金层状混合点阵结构为研究对象。首先设计并制备了由体心立方(BCC)单胞构成的单一点阵结构以及由BCC单胞和面心立方(FCC)单胞组成的2种层状混合点阵结构;其次,利用扫描电子显微镜(SEM)对所制备的点阵结构表面形貌和几何结构进行了表征;再次,采用万能力学试验机对点阵结构进行了准静态单轴压缩试验,并比较了不同点阵结构的力学性能和吸能性能;最后,分析并讨论了单一点阵结构和层状混合点阵结构的变形模式。结果表明:与BCC单一点阵结构相比,层状混合点阵结构TBF-A和TBF-B的弹性模量分别提高27.80%和24.15%,屈服强度分别提高22.96%和18.36%,比吸能分别提高96.01%和33.33%;在变形行为方面,BCC点阵结构沿45°方向整体断裂,而TBF-A和TBF-B层状混合点阵由于增强相(FCC点阵结构)的存在,其断裂仅发生在基体相(BCC点阵结构)区域。

关键词：航空工程点阵结构力学性能吸能性能选区激光熔化

RO、R_(2)O对金刚石砂轮陶瓷结合剂性能的影响

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超硬材料工程 2024年第2期36卷 7-13页

作者：万明赵玉成燕山大学材料科学与工程学院亚稳材料制备科学与技术国家重点实验室河北省秦皇岛066004

以R_(2)O-RO-B_(2)O_(3)-Al_(2)O_(3)-SiO_(2)系玻璃为基础结合剂,研究了不同碱金属氧化物以及碱土金属氧化物的引入对陶瓷结合剂性能的影响。通过X-ray衍射、SEM、三点抗弯等测试方法对制备的陶瓷结合剂样品进行了物相分析、显微结构... 详细信息

以R_(2)O-RO-B_(2)O_(3)-Al_(2)O_(3)-SiO_(2)系玻璃为基础结合剂,研究了不同碱金属氧化物以及碱土金属氧化物的引入对陶瓷结合剂性能的影响。通过X-ray衍射、SEM、三点抗弯等测试方法对制备的陶瓷结合剂样品进行了物相分析、显微结构考察及相关性能的测试。实验结果表明:添加等量的碱土金属氧化物结合剂的各项性能差别不大,主相皆为玻璃相,其中添加SrO的陶瓷结合剂烧结后析出β-石英固溶体含量较多,抗折强度为148 MPa,维氏硬度为HV 813.17,断裂韧性为1.9 MPa·m^(1/2);C2结合剂的烧结温度高出其他两组50℃,C1与C3的结合剂的烧结温度约为590℃,断裂韧性为1.9 MPa·m^(1/2),维氏硬度为HV 790.5,与金刚石的润湿结合较好;将Li_(2)O、Na_(2)O、K_(2)O三种碱金属氧化物两两等质量混合,Na_(2)O与K_(2)O等质量混合后的结合剂的烧结温度较高。B3和C1结合剂对金刚石表现出良好的润湿性。

关键词：金刚石陶瓷结合剂断裂韧性润湿性

DESIGN AND DYNAMICAL SIMULATION TO NEW VIBRATING CENTRIFUGE WITH WIDER FREQUENCY RANGE

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 89-92页

作者： zhao yucheng AN Zengyong ZHANG Kemeng XU Qingyu School of Aerospace Xi＇ an Jiaotong University Xi＇ an 710049 China

A new type of vibrating centrifuge with wider frequency range is designed instead of the traditional one with a single frequency to improve the vibrating effect. With the aid of a new dynamical model, one simulation without considering the visco-elasticity of basis is presented, then the dynamical responses of time and frequency in different scheme are given. The computational results show that the improved vibrating centrifuge possesses a remarkably widened frequency range.

关键词： Wider frequency Vibrating centrifuge Dynamics

基于网格搜索和投票分类模型的喷油器故障诊断研究

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机床与液压 2024年第5期52卷 213-220页

作者：赵玉程李英建沈世民韩玉喜宋杰山东科技大学智能装备学院山东泰安271000

为了提高高压共轨试验台对喷油器检修效率,提出一种基于网格搜索和投票分类模型的喷油器故障自动诊断方法。由于压电喷油器故障数据采集困难,使用AMESim软件模拟不同轨压和脉宽状态下压电喷油器可能出现的多种故障情况。随后,将采集到的... 详细信息

为了提高高压共轨试验台对喷油器检修效率,提出一种基于网格搜索和投票分类模型的喷油器故障自动诊断方法。由于压电喷油器故障数据采集困难,使用AMESim软件模拟不同轨压和脉宽状态下压电喷油器可能出现的多种故障情况。随后,将采集到的1 760组数据使用由随机森林、支持向量机和GBM组成的投票分类模型进行训练,并使用网格搜索法优化各分类器的超参数。实验结果表明:该模型对压电喷油器的5种故障状态及正常状态诊断时的准确率、精确率、召回率和F1-score分别为98.86%、99.13%、98.56%、98.83%,表现出较高的准确性和稳定性。该方法能够快速高效地对喷油器故障情况进行定位。

关键词：投票分类模型网格搜索法压电喷油器故障诊断

FRACTAL DIMENSION OF TIME SERIES APPLIED TO IDENTIFICATION OF CRITICAL SPEED OF JEFFCOTT ROTOR SYSTEM

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 446-448页

作者： zhao yucheng Sun Kun Zhang Yahong Xu Qingyu School of Civil Engineering and Mechanics Xi＇an Jiaotong University Xi＇an 710049 China School of Material Engineering Xi＇an Jiaotong University Xi＇an 710049 China

The dynamical behaviors of logistic map（May＇s model） and duffing equation are studied through fractal dimension of time series at different parameters. It is shown that the parameters of dynamical behaviors can be identified effectively by the curve of fractal dimension with parameter increments. For further verification, the relation between the fractional dimension of time series and rotational speed can be used to identify critical speed effectively by using this method to a plate Jeffoctt rotor system. The numerical and experimental result indicates that the identification of critical parameters is effective.

关键词： Fractal dimension Rotor system Critical speed