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One-pot enantioselective construction of 3,4-dihydro-2H-1,4-oxazines over Ru/Au relay catalysis and its mechanistic serendipity

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Organic Chemistry Frontiers 2022年第1期9卷 102-108页

作者： dongfeng yang Chengyi Wang Yu Wang Guohua Liu Tanyu Cheng Rui Liu Joint Laboratory of International Cooperation of Resource Chemistry of Ministry of Education Key Laboratory of Resource Chemistry of Ministry of Educationand Shanghai Key Laboratory of Rare Earth Functional MaterialsShanghai Normal UniversityShanghaiChina

The preparation of enantiomerically pure 1,4-oxazines remains a continuous challenge in synthetic chemistry because of their potential application in the total synthesis of ***,a one-pot asymmetric transfer hydrogenation/cyclization enantio-relay process catalyzed by Ru and Au bimetallic catalysts was *** enantio-relay process firstly allows the asymmetric transfer hydrogenation of alkynones to form chiral alkynols in the presence of(S,S)-mesityleneRuClTsDPEN(TsDPEN=N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine)and then the chiral alkynols could be converted into 3,4-dihydro-2H-1,4-oxazines in moderate to good yields with excellent enantioselectivity retention accompanied by AuCl(PPh_(3))/AgNTf_(2) and HCOOH.A series of sulfonamide-tethered alkynones were well tolerated in this *** studies indicated that the alkynols formed in the first step were initially transformed into a methylenemorpholine intermediate when AuCl(PPh_(3))/AgNTf_(2) and HCOOH were added,which can be further isomerized into chiral 3,4-dihydro-2H-1,4-oxazines with the addition of a second *** protocol offers not only a practical method to access 3,4-dihydro-2H-1,4-oxazines from alkynones in an enantioselective version,but also enriches the arsenal of gold chemistry from a mechanistic point of view.

关键词： process chiral hydrogenation

Planning for Health: Complexity of Environmental Health and Planning Responses

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China City Planning Review 2018年第1期27卷 32-40页

作者： Liu Zhengying yang dongfeng Liu Jinxin Department of Urban Planning and Design Dalian University of Technology

China's rapid urbanization has led to increasing environmental health problems, which poses great challenges to urban sustainable development. In order to explore the scientific issue of planning for health, this paper firstly analyzes the challenges of spatial planning caused by environmental complexity in terms of health risk, environmental impact, and residents' behavior. And then it puts forward an analytic framework that includes three basic modules, i.e., theoretical model, regional health risk identification, and planning performance assessment, thereby finally proposing six spatial planning strategies according to the objectives of health protection, health promotion, and health equity, on the basis of the actual situation of health risk exposure, environmental friendliness, and the aging level in different cities of China.

关键词： environmental health complexity spatial planning

How Urban Residential Environment Influences the Emotional Health of the Elderly:An Exploration Based on Perception Survey

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China City Planning Review 2022年第1期31卷 51-61页

作者： yang dongfeng Sui Hang School of Architecture&Fine Art Dalian University of TechnologyDalianP.R.China

The daily emotional experience of the elderly is not only related to their mental health,but also influenced and restricted by the urban residential *** studies have discussed the correlation between residential environment and emotional health from the two perspectives of built and social environment,and a variety of theoretical explanations have been ***,it has no explicit and reliable empirical *** order to explore how residential environment influences the emotional health of the elderly,this paper conducts targeted empirical research on the *** on the perception survey,the paper adopts the self-assessed health status,living conditions,and mobility capacity to reflect the emotional experience level of the elderly,and explores the statistical correlation between residential environment factors and the emotional health in combination with an analysis on built and social environment *** is found that the built and social environment factors have remarkable differences in their effects on the emotional *** terms of the social environment,neighborhood involvement has wide positive effects on the self-assessment of all three aspects of health status,living conditions,and mobility capacity;while in terms of the built environment,the landscape of leisure places have positive effects on the self-assessment of both living conditions and mobility *** the end,guided by the concept of active health,the paper puts forward the evidence-based planning strategy from the perspectives of leisure landscape,neighborhood involvement,and travel safety,with the hope to improve the residential environment of the elderly.

关键词： residential environment emotional health leisure landscape neighborhood involvement healthy and active aging

How Urban Green Space Attracts the Elderly:A Preliminary Study on the Relationship Between External Environmental Characteristics and the Frequency of Use

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China City Planning Review 2020年第4期29卷 18-26页

作者： yang dongfeng Wang Xiaoyue Yue Yafei Qian Fang Department of Urban Planning Dalian University of TechnologyDalianP.R.China

A high-grade green space environment will provide necessary environmental support to the outdoor activities of disadvantaged groups including the elderly and is thus helpful for promoting their physical activity level and life *** paper takes the urban area of Dalian City as an example and divides the external environmental characteristics of a green space into three aspects including the diversity degree of facilities,the richness level of street functions,and the mixing degree of land *** on the data of a survey on activities by elderly in green space,the paper conducts an in-depth study on the statistical correlation between the external environmental characteristics of green space and the frequency of use by the *** study shows that diversified facility types around a green space are conducive to a rise in the frequency of use of this space by the elderly,out of which the effect of functional facilities such as school and food market is the most *** addition,being adjacent to streets full of daily life or being mixed with residential land use will increase the frequency of use of the green space by the *** paper puts forward certain environmental upgrading strategies for green space from the perspective of external environmental characteristics in order to help build up green space that is use-friendly to the elderly.

关键词： urban green space attraction the elderly frequency of use external environment

Spatial Logic and Risks in China's Rapid Urbanization under Global Complexity

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China City Planning Review 2013年第1期22卷 15-23页

作者： dongfeng yang Fang QIAN Department of Urban Planning Dalian University of Technology

China's rapid urbanization in the past 30 years can be abstracted as a spatial-temporal product of the socio-economic mechanism relying on productive factors, which represents the sustained dynamics from labor demographic bonus to land capital discount. In the context of the current increasing global complexity, this paper points out that this kind of productive factor-based spatial logic not only has structural deficiencies, but also potentially brings about the environmental, economic, social, and political risks in multiple dimensions as follows: first, the crises in regional resources and environment due to the market distortion of productive factors; second, the disappearance of industrial growth impetus due to the investment preference to land urbanization; third, the social polarization caused by the incomplete urbanization of immigrates; fourth, the overdraft of government credit as a result of the unbalanced urbanization of population, industry, and land. Under such a circumstance, the paper proposes a transition of China's existing urbanization policies, so as to achieve the objective of sustainable urbanization in the future.

关键词： global complexity urbanization spatial logic potential risk sustainable development

Analysis of Development Regulation in Chinese Regulatory Planning towards the Main Function Zoning Strategy

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Journal of Civil Engineering and Architecture 2014年第9期8卷 1178-1184页

作者： Chengzhi Yin dongfeng yang School of Public Policy and Management Tsinghua University Beo'ing 100000 China School of Architecture and Fine Arts Dalian University of Technology Dalian 116000 China

China is in a process of rapid urbanization. However, along with the dramatically economic growth, there constantly emerges environmental and social constraints which may be great challenges of China＇s future sustainable development. In order to optimize the developmental mode, the latest national plan, ＂The 12th National Economic and Social Development Plan （2011-2015）＂, is establishing the ＂Main Function Zoning Strategy＂, which could be considered as a new prototype of national spatial plan and may cover all Chinese territories. Based on the latest ＂Main Function Zoning Strategy＂ stipulated in ＂The 12th National Economic and Social Development Plan （2011-2015）＂, the article builds main interlinks between the spatial development strategy and urban regulatory planning. Secondly, regulation factors in Chinese regulatory planning, which may implement the task of main function zoning, have been clarified and categorized. For each regulation factor, its regulation capability is defined by applying a coding method developed by the author. Finally, according to the output of the study, the spatial regulation approaches to implementing the ＂Main Function Zoning Strategy＂ in Chinese regulatory planning are analyzed.

关键词： China Main Function Zoning Strategy urban planning development regulation.

Germplasm resources and secondary metabolism regulation in Reishi mushroom(Ganoderma lucidum)

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Chinese Herbal Medicines 2023年第3期15卷 376-382页

作者： Xinyu He Yiwen Chen Zhenhao Li Ling Fang Haimin Chen Zongsuo Liang Ann Abozeid Zongqi yang dongfeng yang Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province College of Life Sciences and MedicineZhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Shouxiangu Botanical Drug Institute Co. Ltd.Hangzhou 310018China Shaoxing Academy of Biomedicine Co. Ltd.of Zhejiang Sci-Tech UniversityZhejiang Engineering Research Center for Development Technology of Medicinal and Edible Health FoodShaoxing 312000China Botany and Microbiology Department Faculty of ScienceMenoufia UniversityShebin Elkoom 32511Egypt

Ganoderma lucidum is a valuable medical macrofungus with a myriad of diverse secondary metabolites,in which triterpenoids are the major *** paper introduced the germplasm resources of genus Ganoderma from textual research,its distribution and identification at the molecular *** we overviewed *** in the components,the biological activities and biosynthetic pathways of ganoderic acid,aiming to provide scientific evidence for the development and utilization of *** germplasm resources and the biosynthesis of ganoderic acid.

关键词： chemical constituents Ganoderma lucidum(Leyss.ex Fr.)Karst. ganoderic acid germplasm resources pharmacological activities secondary metabolism regulation

Millet Origin Identification Model Based on Near-infrared Spectroscopy

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Agricultural Biotechnology 2024年第3期13卷 31-33页

作者： Penghe LYU dongfeng yang College of Information and Electrical Engineering Heilongjiang Bayi Agricultural UniversityDaqing 163700China

[Objectives]This study was conducted to clarify the difference of millet from different producing areas in near-infrared spectroscopy(NIRS)modeling.[Methods]Millet samples from six different regions were collected for NIRS analysis,and an origin identification model based on BP neural network was *** competitive adaptive reweighted sampling(CARS)algorithm was used to extract characteristic wavelength variables,and a CARS-BP model was established on this ***,the CARS-BP model was compared with support vector machine(SVM),partial least squares discriminant analysis(PLS)and KNN models.[Results]The characteristic wavelengths were extracted by CARS,and the number of variables was reduced from 1845 to *** discrimination accuracy of the CARS-BP model for the samples from six producing areas reached 98.1%,which was better than SVM,PSL and KNN models.[Conclusions]NIRS can quickly and accurately identify the origin of millet,providing a new method and way for the origin identification and quality evaluation of millet.

关键词： Millet Identification of origin CARS-BP model NIR

Two CYP82D Enzymes Function as Flavone Hydroxylases in the Biosynthesis of Root-Specific 4＇-Deoxyflavones in Scutellaria baicalensis

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Molecular Plant 2018年第1期11卷 135-148页

作者： Qing Zhao Meng-Ying Cui Olesya Levsh dongfeng yang Jie Liu Jie Li Lionel Hill Lei yang Yonghong Hu Jing-Ke Weng Xiao-Ya Chen Cathie Martin Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical Garden Shanghai Chenshan Plant Science Research Center Chinese Academy of Sciences Shanghai China Department of Metabolic Biology John Innes Centre Norwich NR4 7UH UK Whitehead Institute for Biomedical Research 455 Main Street Cambridge MA 02142 USA Department of Biology Massachusetts Institute of Technology Cambridge MA 02139 USA College of Life Sciences Zhejiang Sci-Tech University Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province Hangzhou 310018 China State Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant Sciences Shanghai Institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai China These authors contributed equally to this article.

Baicalein, wogonin, and their glycosides are major bioactive compounds found in the medicinal plant Scutellaria baicalensis Georgi. These flavones can induce apoptosis in a variety of cancer cell lines but have no effect on normal cells. Furthermore, they have many additional benefits for human health, such as antioxidant, antiviral, and liver-protective properties. Here, we report the isolation and characterization of two CYP450 enzymes, SbCYP82D1.1 and SbCYP82D2, which function as the flavone 6-hydroxylase （F6H） and flavone 8-hydroxylase （F8H）, respectively, in S. baicalensis. SbCYP82D1.1 has broad substrate speci- ficity for flavones such as chrysin and apigenin and is responsible for biosynthesis of baicalein and scutel- larein in roots and aerial parts of S. baicalensis, respectively. When the expression of SbCYP82D1.1 is knocked down, baicalin and baicalein levels are reduced significantly while chrysin glycosides accumulate in hairy roots. SbCYP82D2 is an F8H with high substrate specificity, accepting only chrysin as its substrate to produce norwogonin, although minor 6-hydroxylation activity can also be detected. Phylogenetic analysis suggested that SbCYP82D2 might have evolved from SbCYP82D1.1 via gene duplication followed by neofunctionalization, whereby the ancestral F6H activity is partially retained in the derived SbCYP82D2.

关键词： Scutellaria baicalensis Huangqin baicalein wogonin flavone 6-hydroxylase flavone 8-hydroxylase