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The biosynthesis of asiaticoside and madecassoside reveals tandem duplication-directed evolution of glycoside glycosyltransferases in the Apiales

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Plant Communications 2024年第10期5卷 166-179页

作者： Xiaoyang Han jingyi zhao Hong Zhou Xuan Zhou Zixin Deng Zhenhua Liu Yi Yu Department of Gastroenterology Zhongnan Hospital of Wuhan UniversityHubei Clinical Center and Key Laboratory of Intestinal and Colorectal DiseaseSchool of Pharmaceutical SciencesWuhan UniversityWuhan 430071China Joint Center for Single Cell Biology School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Non-Food Biomass and Enzyme Technology Guangxi Academy of SciencesNanning 530007China

Certain plant species within the Apiales order accumulate triterpenoid saponins that feature a distinctive glucose-glucose-rhamnose(G-G-R)sugar chain attached at the C-28 position of the pentacyclic triterpene *** recently,the genomic basis underlying the biosynthesis and evolution of this sugar chain has remained *** this study,we identified two novel glycoside glycosyltransferases(GGTs)that can sequentially install the sugar chain’s second D-glucose and third L-rhamnose during the biosynthesis of asiaticoside and madecassoside,two representative G-G-R sugar chain-containing triterpenoid saponins produced by Centella *** assays revealed the remarkable substrate promiscuity of the two GGTs and the key residues crucial for sugar-donor selectivity of the glucosyltransferase and *** further identified syntenic tandem gene duplicates of the two GGTs in the Apiaceae and Araliaceae families,suggesting a well-conserved genomic basis underlying sugar chain assembly that likely has evolved in the early ancestors of the Apiales ***,expression patterns of the two GGTs in pierced leaves of *** were found to be correlated with the production of asiaticoside and madecassoside,implying their involvement in host defense against herbivores and *** work sheds light on the biosynthesis and evolution of complex saponin sugars,paving the way for future engineering of diverse bioactive triterpenoids with unique glycoforms.

关键词： triterpenoid saponin glycoside glycosyltransferases biosynthesis asiaticoside madecassoside Centella asiatica

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Life prediction and test period optimization research based on small sample reliability test of hydraulic pumps

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High Technology Letters 2017年第1期23卷 63-70页

作者：郭锐 Ning Chao zhao jingyi Wang Ping Shi Yu Zhou Jinsheng Luo Jing Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan UniversityKey Laboratory of Advanced Forging&Stamping Technology and Science(Yanshan University)Qinhuangdao 066004P.R.China Huachuang Tianyuan Industrial Developing Co. LtdLangfang 065000P.R.China College of Art and Design Yanshan UniversityQinhuangdao 066004P.R.China Beijing Research Institute of Automation for Machinery Industry Beijing 100120P.R.China

Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-saving and power recovery,a small sample hydraulic pump reliability test rig is built,and the service life of hydraulic pump is predicted,and then the sampling period of reliability test is optimized. On the basis of considering the performance degradation mechanism of hydraulic pump,the feature information of degradation distribution of hydraulic pump volumetric efficiency during the test is collected,so an optimal degradation path model of feature information is selected from the aspect of fitting accuracy,and pseudo life data are obtained. Then a small sample reliability test of period constrained optimization search strategy for hydraulic pump is constructed to solve the optimization problem of the test sampling period and tightening end threshold,and it is verified that the accuracy of the minimum sampling period by the non-parametric hypothes is tested. Simulation result shows it could possess instructional significance and referenced value for hydraulic pump reliability life evaluation and the test's research and design.

关键词： hydraulic pump small sample test volumetric efficiency degradation path model life span period optimal

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Intrinsic luminescence from metal nanostructures and its applications

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Chinese Physics B 2018年第9期27卷 88-96页

作者： Weidong Zhang Te Wen Yuqing Cheng jingyi zhao Qihuang Gong Guowei Lti 2State Key Laboratory tbr Mesoscopic Physics ＆ Collaborative Innovation Center of Quantum MatterDepartment of Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Intrinsic luminescence from metal nanostructures complements conventional scattering and absorption behaviors and has many interesting and unique features. This phenomenon has attracted considerable research attention in recent years because of its various potential applications. In this review, we discuss recent advances in this field, summarize potential applications for this type of luminescence, and compare theoretical models to describe the phenomena. On the basis of the excitation process, the characteristic features and corresponding applications are summarized briefly in three parts, namely, continuous-wave light, pulsed laser, and electron excitation. A universal physical mechanism likely operates in all these emission processes regardless of differences in the excitation processes; however, there remains some debate surrounding the details of the theoretical model. Further insight into these luminescence phenomena will not only provide a deeper fundamental understanding of plasmonic nanostructures but will also advance and extend their applications.

关键词： metal nanostructure luminescence surface plasmon spectroscopy

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基底材料对润滑油中金属元素LIBS检测的影响

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沈阳理工大学学报 2025年第1期44卷 78-84页

作者：赵静怡段皓蔡明洋李倩李业秋沈阳理工大学理学院沈阳110159

润滑油中金属元素的含量和成分的变化能反映发动机的使用状态。通过对比四种基底(Al、Ni、Zn、Cu)增强下润滑油中金属元素BaⅡ455.4 nm的激光诱导击穿光谱(LIBS)特性,对不同基底材料的激发效果进行了评价,并利用多元线性回归模型建立了B... 详细信息

润滑油中金属元素的含量和成分的变化能反映发动机的使用状态。通过对比四种基底(Al、Ni、Zn、Cu)增强下润滑油中金属元素BaⅡ455.4 nm的激光诱导击穿光谱(LIBS)特性,对不同基底材料的激发效果进行了评价,并利用多元线性回归模型建立了Ba元素激发效果与基底元素物理特性的联系。结果表明:第一电离能、蒸发潜热、热传导率对润滑油中金属元素的激发效果影响较小,且呈正相关;相对原子质量、原子序数、熔化潜热、密度对润滑油中金属元素的激发效果影响较大,且呈负相关。该结果为润滑油金属元素LIBS检测过程中基底材料的选择提供了依据,并为提高金属元素检测准确率和检出限提供了一种可行性方案,对发动机故障检测有重要意义。

关键词：激光诱导击穿光谱润滑油基底材料多元线性回归

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Discussion on applying an analytical method to optimize the anti-freeze design parameters for underground water pipelines in seasonally frozen areas

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Research in Cold and Arid Regions 2016年第6期8卷 467-476页

作者： Ji Chen jingyi zhao Kun Li Yu Sheng State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-environment and Resources Chinese Academy of Science Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-environment and Resources Chinese Academy of Science School of Civil Engineering and Architecture Southwest Petroleum University

Adopting the quasi-three-dimensional （Quasi-3D） numerical method to optimize the anti-freeze design parameters of an underground pipeline usually involves heavy numerical calculations. Here, the fitting formulae between the safe con-veyance distance （SCD） of a water pipeline and six influencing factors are established based on the lowest water temper-ature （LWT） along the pipeline axis direction. With reference to the current widely used anti-freeze design approaches for underground pipelines in seasonally frozen areas, this paper first analyzes the feasibility of applying the maximum frozen penetration （MFP） instead of the mean annual ground surface temperature （MAGST） and soil water content （SWC） to calculate the SCD. The results show that the SCD depends on the buried depth if the MFP is fixed and the variation of the MAGST and SWC combination does not significantly change the SCD. A comprehensive formula for the SCD is estab-lished based on the relationships between the SCD and several primary influencing factors and the interaction among them. This formula involves five easy-to-access parameters： the MFP, buried depth, pipeline diameter, flow velocity, and inlet water temperature. A comparison between the analytical method and the numerical results based on the Quasi-3D method indicates that the two methods are in good agreement overall. The analytic method can be used to optimize the anti-freeze design parameters of underground water pipelines in seasonally frozen areas under the condition of a 1.5 safety coefficient.

关键词： Quasi-3D method analytical method maximum frozen penetration underground water pipeline seasonally frozen area

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National guidelines for diagnosis and treatment of breast cancer 2022 in China(English version)

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Chinese Journal of Cancer Research 2022年第3期34卷 151-175页

作者：无 Xinguang Wang Xue Chen Dongfeng Niu Yang Yang jingyi zhao National Health Commission of the People’s Republic of China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education Beijing) Peking University Cancer Hospital&Institute

Contents 1. Breast cancer screening 1.1 Recommendations for females at normal risk 1.1.1 Age 20-39 years old 1.1.2 Age 40-69 years old 1.1.3 Age≥70 years old 1.2 Recommendations for females at increased risk 2. Diagnosis of breast cancer 2.1 Clinical manifestations 2.1.1 Breast lump 2.1.2 Nipple discharge 2.1.3 Skin changes 2.1.4 Abnormalities in nipple and areola 2.1.5 Enlarged axillary lymph nodes。

关键词： diagnosis breast cancer

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How to Teach Vocabulary in Context

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基础教育外语教学研究 2016年第12期 56-59页

作者： zhao jingyi No. 1 High School Jilin Jilin 132012 China

It is widely accepted that vocabulary teaching is at the base of our understanding of *** EFL learners,Chinese students have been used to learning English vocabulary in the Chinese way,*** always tend to apply rote me... 详细信息

关键词：基础教育外语教学英语教学访求

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Rice transcription factors OsLBD37/38/39 regulate nitrate uptake by repressing OsNRT2.1/2.2/2.3 under high-nitrogen conditions

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The Crop Journal 2022年第6期10卷 1623-1632页

作者： Xinxin Zhu Dujun Wang Lijuan Xie Tao Zhou jingyi zhao Qian Zhang Meng Yang Wenjuan Wu Xingming Lian National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research(Wuhan) Huazhong Agricultural UniversityWuhan 430070HubeiChina

Nitrate(NO_(3)^(-)) uptake involves a finely regulated and complex multilevel response *** the molecular mechanism of nitrate uptake may lead to improving the growth and productivity of plants in the presence of dynamic variation in nitrate *** this study,we identified three lateral organ boundaries domain(LBD)transcription factors,OsLBD37,OsLBD38,and OsLBD39,as regulators of nitrate uptake in response to nitrogen(N)***37,OsLBD38,and OsLBD39 were induced by ammonium and glutamine in rice *** or collective knockout of OsLBD37,OsLBD38,and OsLBD39 led to increased concentrations of nitrate and increased expression of OsNRT2.1,OsNRT2.2,and OsNRT2.3respectively under high-N conditions,whereas overexpression of each of these three LBD genes produced opposite effects where N accumulation was ***-luciferase reporter assay further confirmed that OsLBD37,OsLBD38,and OsLBD39 possessed transcription inhibitory activities in rice protoplast cells,downregulating the expression of OsNRT2.1/OsNRT2.2/*** two-hybrid and bimolecular fluorescence complementation assays showed that OsLBD37 interacted with OsLBD37,OsLBD38,and OsLBD39in the ***,these results show that OsLBD37,OsLBD38,and OsLBD39 collaborate to inhibit the expression of OsNRT2.1/OsNRT2.2/OsNRT2.3 transporters under N-sufficient conditions,thereby helping rice plants avoid excessive nitrate accumulation that may affect their growth.

关键词： Oslbd37/Oslbd38/Oslbd39 Transcription factor Nitrate uptake Rice

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Field observation of the thermal disturbance and freezeback processes of cast-in-place pile foundations in warm permafrost regions

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Research in Cold and Arid Regions 2023年第1期15卷 18-26页

作者： Xin Hou Ji Chen YouQian Liu PengFei Rui jingyi zhao ShouHong Zhang HaiMing Dang Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment State Key Laboratory of Frozen Soil EngineeringNorthwest Institute of Eco-Environmental and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China China Railway Qinghai-Tibet Group Co.Ltd XiningQinghai 810007China

The bearing capacity of pile foundations is affected by the temperature of the frozen soil around pile *** construction process and the hydration heat of cast-in-place(CIP)pile foundations affect the thermal stability of *** this paper,temperature data from inside multiple CIP piles,borehole observations of ground thermal status adjacent to the foundations and local weather stations were monitored in warm permafrost regions to study the thermal influence process of CIP pile *** following conclusions are drawn from the field observation data.(1)The early temperature change process of different CIP piles is different,and the differences gradually diminish over time.(2)The initial concrete temperature is linearly related with the air temperature,net radiation and wind speed within 1 h before the completion of concrete pouring;the contributions of the air temperature,net radiation,and wind speed to the initial concrete temperature are 51.9%,20.3%and 27.9%,respectively.(3)The outer boundary of the thermal disturbance annulus is approximately 2 m away from the pile *** took more than 224 days for the soil around the CIP piles to return to the natural permafrost temperature at the study site.

关键词： Permafrost Cast-in-place pile foundations Thermal disturbance Freezeback process Initial concrete temperature

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RELIABILITY ANALYSIS OF THE PRIMARY CYLINDER OF THE 10MN HYDRAULIC PRESS

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Chinese Journal of Mechanical Engineering 2000年第4期13卷 295-300页

作者： zhao jingyi Chen Zhuoru (School of Mechatronic Engineering,Harbin Institute of Technololgy) Wang Yiqun Su Erhuang (Yansan UniversityHarbin Institute of Technololgy) 哈尔滨工业大学黑龙江哈尔滨燕山大学河北秦皇岛

According to the demand of high reliability of the primary cylinder of the hydraulic press, the reliability model of the primary cylinder is built after its reliability analysis. The stress of the primary cylinder is analyzed by finite element software—MARC, and the structure reliability of the cylinder based on stress strength model is predicted, which would provide the reference to the design.

关键词： Hydraulic press Fault tree analysis Reliability

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