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Structural diversification of bioactive bibenzyls through modular co-culture leading to the discovery of a novel neuroprotective agent

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Acta Pharmaceutica Sinica B 2023年第4期13卷 1771-1785页

作者： Yuyu Liu xinnan Li Songyang Sui Jingshu Tang Dawei Chen Yuying Kang Kebo Xie Jimei Liu Jiaqi Lan Lei Wu Ridao Chen Ying Peng Jungui dai State Key Laboratory of Bioactive Substance and Function of Natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugsand NHC Key Laboratory of Biosynthesis of Natural ProductsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Bibenzyls,a kind of important plant polyphenols,have attracted growing attention for their broad and remarkable pharmacological activities.However,due to the low abundance in nature,uncontrollable and environmentally unfriendly chemical synthesis processes,these compounds are not readily accessible.Herein,one high-yield bibenzyl backbone-producing Escherichia coli strain was constructed by using a highly active and substrate-promiscuous bibenzyl synthase identified from Dendrobium officinale in combination with starter and extender biosynthetic enzymes.Three types of efficiently postmodifying modular strains were engineered by employing methyltransferases,prenyltransferase,and glycosyltransferase with high activity and substrate tolerance together with their corresponding donor biosynthetic modules.Structurally different bibenzyl derivatives were tandemly and/or divergently synthesized by co-culture engineering in various combination modes.Especially,a prenylated bibenzyl derivative(12)was found to be an antioxidant that exhibited potent neuroprotective activity in the cellular and rat models of ischemia stroke.RNA-seq,quantitative RT-PCR,and Western-blot analysis demonstrated that 12 could up-regulate the expression level of an apoptosis-inducing factor,mitochondria associated 3(Aifm3),suggesting that Aifm3 might be a new target in ischemic stroke therapy.This study provides a flexible plug-and-play strategy for the easy-to-implement synthesis of structurally diverse bibenzyls through a modular co-culture engineering pipeline for drug discovery.

关键词： Bibenzyls Modular co-culture engineering Promiscuous enzymes Neuroprotective agent Aifm3 Dendrobium officinale

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基于眼动追踪技术下明代汉服设计要素研究

丝绸 2023年第9期60卷 120-127页

作者：张超代沁伶姚欣楠龙飞杨柳春西南林业大学艺术与设计学院昆明650224

汉服是中国优秀传统文化的重要组成部分,文章以明代汉服为研究对象,汉服的版型色彩、图案为设计变量,探讨这些设计要素对当代年轻用户的视觉注意、认知加工程度及满意度的影响。采用眼动追踪实验获取不同汉服设计要素的组合,年轻用户群... 详细信息

汉服是中国优秀传统文化的重要组成部分,文章以明代汉服为研究对象,汉服的版型色彩、图案为设计变量,探讨这些设计要素对当代年轻用户的视觉注意、认知加工程度及满意度的影响。采用眼动追踪实验获取不同汉服设计要素的组合,年轻用户群体的客观行为反应数据,并通过量表进行主观满意度测量。明代汉服的版型、色彩、图案三种基本设计要素分别对视觉注意、认知加工程度、主观满意度具有主效应,且具有显著交互作用。研究表明,圆领袍的版型设计、色彩中的赭红色、图案中的仙鹤纹更加吸引用户的视觉注意,用户的认知加工程度及主观满意度的评价较高。

关键词：汉服眼动指标视觉注意认知加工程度用户满意度多因素方差分析

Management of triplet excitons transition:fine regulation of Förster and dexter energy transfer simultaneously

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Light(Science & Applications) 2024年第2期13卷 302-315页

作者： Jiaqiang Wang Yujie Yang xinnan Sun Xiaoning Li Liyao Zhang Zhen Li Institute of Molecular Aggregation Science Tianjin UniversityTianjin300072China School of Life Sciences Tianjin UniversityTianjin300072China Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhan430072China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430072China Joint School of National University of Singapore Tianjin UniversityInternational Campus of Tianjin UniversityBinhai New CityFuzhou350207China

Understanding and management of triplet excitons transition in the same molecule remain a great challenge.Hence,for the first time,by host engineering,manageable transitions of triplet excitons in a naphthalimide derivative NDOH were achieved,and monitored through the intensity ratio(ITADF/IRTP)between thermally activated delayed fluorescence(TADF)and room-temperature phosphorescence(RTP).Energy differences between lowest triplet excited states of host and guest were changed from 0.03 to 0.17 eV,and ITADF/IRTP of NDOH decreased by 200 times,thus red shifting the afterglow color.It was proposed that shorter conjugation length led to larger band gaps of host materials,thus contributing to efficient Dexter and inefficient Förster energy transfer.Interestingly,no transition to singlet state and only strongest RTP with quantum yield of 13.9%could be observed,when PBNC with loosest stacking and largest band gap acted as host.This work provides novel insight for the management and prediction of triplet exciton transitions and the development of smart afterglow materials.

关键词： materials transition transitions

Regulatory effect of traditional Chinese medicines on signaling pathways of process from chronic atrophic gastritis to gastric cancer

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Chinese Herbal Medicines 2022年第1期14卷 5-19页

作者： xinnan Liu Shuping Wang Jingyang Li Jingze Zhang dailin Liu Tianjin Modern Innovation Chinese Medicine Technology Co. Ltd.Tianjin 300380China Tianjin University of Traditional Chinese Medicine Tianjin 301617China Department of Pharmacy Tianjin Provincial Corps HospitalChinese People’s Armed Police ForcesTianjin 300162China Logistics College of Chinese People’s Armed Police Forces Tianjin 300309China

Chronic atrophic gastritis(CAG),a common disease of digestive system,is an extremely important cause of gastric cancer(GC).The occurrence and development of CAG involves the abnormality of multiple signaling pathways.Traditional Chinese medicines(TCMs)has the advantages of mild action,multi-target and small adverse reaction,etc.,which broadens the way for the treatment of the disease,and TCMs can play a therapeutic role by regulating multiple signaling pathways.In this review,based on the related experiments of TCMs and Chinese herbal compounds in recent years,the related literatures were searched and 10 kinds of signaling pathways involved were summarized,in order to provide a reference for further research on reversing or delaying the progress of CAG and preventing gastric cancer.

关键词： chronic atrophic gastritis gastric cancer signaling pathway traditional Chinese medicines

Quantitative micro-electrochemical study of duplex stainless steel 2205 in 3.5wt%NaCl solution

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International Journal of Minerals,Metallurgy and Materials 2022年第11期29卷 2053-2063页

作者： Shuangyu Cai Keke Lu xinnan Li Lei Wen Feifei Huang Ying Jin National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Innovation Group of Marine Engineering Materials and Corrosion Control Southern Marine Science and Engineering Guangdong LaboratoryZhuhai 519080China

Duplex stainless steels(DSSs)are suffering from various localized corrosion attacks such as pitting,selective dissolution,crevice corrosion during their service period.It is of great value to quantitatively analyze and grasp the micro-electrochemical corrosion behavior and related mechanism for DSSs on the micrometer or even smaller scales.In this work,scanning Kelvin probe force microscopy(SKPFM)and energy dispersive spectroscopy(EDS)measurements were performed to reveal the difference between the austenite phase and ferrite phase in microregion of DSS 2205.Then traditional electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization(PDP)tests were employed for micro-electrochemical characterization of DSS 2205 with different proportion phases inϕ40 andϕ10μm micro holes.Both of them can only be utilized for qualitative or semi-quantitative micro-electrochemical characterization of DSS 2205.Coulostatic perturbation method was employed for quantitative micro-electrochemical characterization of DSS 2205.What is more,the applicable conditions of coulostatic perturbation were analyzed in depth by establishing a detailed electrochemical interface circuit.A series of microregion coulostatic perturbations for DSS 2205 with different proportion phases inϕ10μm micro holes showed that as the austenite proportion increases,the corresponding polarization resistance of microregion increases linearly.

关键词： duplex stainless steel 2205 quantitative micro-electrochemical study electrochemical impedance spectroscopy coulostatic perturbation scanning Kelvin probe force microscopy

Chemical constituents and pharmacological activities of medicinal plants from Rosa genus

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Chinese Herbal Medicines 2022年第2期14卷 187-209页

作者： Yansheng Wang Yanmin Zhao xinnan Liu Jingyang Li Jingze Zhang dailin Liu Tianjin University of Traditional Chinese Medicine Tianjin 301617China Tianjin Modern Innovation Chinese Medicine Technology Co. Ltd.Tianjin 300380China Logistics College of Chinese People’s Armed Police Forces Tianjin 300309China

The genus Rosa(Rosaceae family)includes about 200 species spread in the world,and this genus shows unique advantages in medicine and food.To date,several scholars concentrated on compounds belonging to flavonoids,triterpenes,tannins,polysaccharide,phenolic acids,fatty acids,organic acids,carotenoids,and vitamins.Pharmacological effects such as antineoplastic and anti-cancer properties,antiinflammatory,antioxidant,liver protection,regulate blood sugar,antimicrobial activity,antiviral activity,as well as nervous system protection and cardiovascular protection were wildly reported.This article reviews the chemical constituents,pharmacological effects,applications and safety evaluations of Rosa plants,which provides a reference for the comprehensive utilization of medicine and food resources and gives a scientific basis for the development of medicinal plants of the genus Rosa.

关键词： medicine and food homology pharmacological effect phytochemistry Rosa safety

Isolation,identification and artificial inoculation of Rhizoctonia solani on pear during storage

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Horticultural Plant Journal 2023年第1期9卷 73-76页

作者： Xiaohui Jia Jianing Xu Yushuo Wu xinnan Zhang Yanmin Du Wenhui Wang Research Institute of Pomology Chinese Academy of Agricultural SciencesXingchengLiaoning 125100China

Pear is a fruit crop of worldwide importance and cold storage is an integral part of the production and distribution of pears.An uncharacterized fungal disease has been observed on‘Huangguan’pear fruit during cold storage in Hebei Province.The fungus was consistently isolated from diseased fruit by routine tissue separation method,and shown to be the causal agent according to Koch postulates.Based on its morphology,molecular characteristics,pathogenicity and ITS sequence,the fungus was identified as Rhizoctonia solani.This study recorded postharvest fruit rot caused by Rhizoctonia solani on pear fruit in China.

关键词： Pear Pathogenicity Postharvest Rhizoctonia solani Fruit rot

时速350 km及以上高速铁路GSM-R系统QoS性能研究

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铁道通信信号 2021年第11期57卷 46-50页

作者：代赛费丹姚欣楠胡晓红中铁第四勘察设计院集团有限公司武汉430063 北京交通大学北京100044

针对GSM-R高速适应性研究,借助无线信道仿真仪及GSM-R网络终端设备,搭建了高速铁路场景下的半实物仿真系统;在分析高铁场景多普勒特征的基础上,开展了GSM-R QoS性能测试,得到了越区切换场景下的UDP传输平均时延和丢包率的测试结果,直接... 详细信息

针对GSM-R高速适应性研究,借助无线信道仿真仪及GSM-R网络终端设备,搭建了高速铁路场景下的半实物仿真系统;在分析高铁场景多普勒特征的基础上,开展了GSM-R QoS性能测试,得到了越区切换场景下的UDP传输平均时延和丢包率的测试结果,直接反映了列车运行速度对以上指标的影响;进一步分析了不同列车运行速度下的最低覆盖电平要求,给出了单小区下行接收质量测试结果,并分析了列车运行速度为500 km/h时多径效应对接收质量的影响。本研究成果可用于支撑GSM-R网络设计,为我国高速铁路的进一步提速提供参考。

关键词：高速铁路铁路数字移动通信系统半实物仿真服务质量性能研究

Production plan for perishable agricultural products with two types of harvesting

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Information Processing in Agriculture 2020年第1期7卷 83-92页

作者： Jing Li xinnan Gao Biao Guo Muyuan Wu Faculty of Engineering Nanjing Agricultural UniversityNanjing 210031PR China

Many crops in China have two or more harvesting methods;however,little research has focused on this phenomenon.The current study proposes an operational model that looks to maximize grower profits.This model considers a production plan for a perishable crop that has two harvesting methods:harvesting unripe produce at a lower operational cost but with a long lead time,and harvesting ripe crops at a higher operational cost but with quick turnaround.This study proposes a heuristic algorithm by which to pinpoint the optimal plan for the model;the model results indicate that for a crop with two harvesting methods,significant savings can be obtained by applying an optimal production plan.The current study’s main contribution is a production model for crops that feature two harvesting methods and for which the market poses varying demands.

关键词： Perishable products Heuristic algorithm Harvesting types