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Reform of Hospitality English Teaching Based on the Educational Concept of Outcome-Based Education(OBE) 被引量:1
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作者 Chong Zhang 《Journal of Contemporary Educational Research》 2024年第1期58-64,共7页
The Outcome-Based Education(OBE)educational concept,proposed by renowned American educator Spady,aims to guide students in mastering learning laws and ultimately achieving expected learning outcomes.The application of... The Outcome-Based Education(OBE)educational concept,proposed by renowned American educator Spady,aims to guide students in mastering learning laws and ultimately achieving expected learning outcomes.The application of OBE educational concept in Hospitality English curriculum not only can effectively enhance the learning effect but also promote the reform of the Hospitality English curriculum,thus improving students’learning enthusiasm.Therefore,taking the Hospitality English curriculum as an example,this paper points out the existing problems in the teaching of this course and suggests the reform measures based on the OBE teaching concept,hoping to provide guidelines for related educational work. 展开更多
关键词 Outcome-Based Education(OBE)educational concept Hospitality English curriculum Teaching reform Practical strategy
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Elucidating the structure-activity relationship of Cu-Ag bimetallic catalysts for electrochemical CO_(2) reduction
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作者 Qining Huang Lili Wan +1 位作者 Qingxuan Ren Jingshan Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期345-351,I0009,共8页
Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential fo... Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential for catalyst design.Herein,we prepared two Cu-Ag bimetallic catalysts with Ag nanoparticles attached to the top or the bottom of Cu nanowires.When tested in a flow cell,the Cu-Ag catalyst with Ag nanoparticles on the bottom achieved a faradaic efficiency of 54%for ethylene production,much higher than the catalyst with Ag nanoparticles on the top.The catalysts were further studied in the H-cell and zero-gap MEA cell.It was found that placing the two metals in the intensified reaction zone is crucial to triggering the tandem reaction of bimetallic catalysts.Our work elucidates the structure-activity relationship of bimetallic catalysts for CO_(2) reduction and demonstrates the importance of considering both catalyst structures and cell characteristics to achieve high activity and selectivity. 展开更多
关键词 Electrochemical CO_(2)reduction Bimetallic catalyst CU-AG Structure-activity relationship
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The Relationship between Father-Love Absence and Loneliness:Based on the Perspective of the Social Functionalist Theory and the Social Needs Theory
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作者 Yaping Zhou He Zhong +1 位作者 Xiaojun Li Yanhui Xiang 《International Journal of Mental Health Promotion》 2024年第2期139-148,共10页
Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-lov... Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-love absence on individual loneliness are not clear.Based on the social functionalist theory and the social needs theory,this study examines the influence of individual fatherlove absence on loneliness and its underlying mechanisms.A questionnaire survey was administered to 319 junior high school students and 1,476 high school students.The results showed that adolescents with father-love absence had higher levels of loneliness,and that father-love absence affected loneliness levels through mediating pathways of individual gratitude,peer relationships,and gratitude to peer relationships.This study not only confirms the negative effects of father-love absence on adolescents’loneliness,but also explains the mediate roles of individual gratitude and peer relationships.It enriches the theoretical system related to family education and has important theoretical and practical implications for further interventions on adolescents’mental health from the perspective of fatherless parenting. 展开更多
关键词 Father-love absence LONELINESS GRATITUDE peer relationships
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Modern pollen-vegetation relationships along altitudinal vegetation belts in the Leigong Mountain of southwestern China
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作者 LI Shuming ZHAO Wenwei +7 位作者 WEI Lisi REN Weihe GU Qinran WU Siqi JI Yang YANG Ziteng ZHUANG Rui CHEN Chunzhu 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2249-2262,共14页
Understanding the distribution,dispersal,and correlation of modern pollen with vegetation in mountainous regions is essential for establishing accurate modern analogs for fossil pollen records.This study,conducted in ... Understanding the distribution,dispersal,and correlation of modern pollen with vegetation in mountainous regions is essential for establishing accurate modern analogs for fossil pollen records.This study,conducted in Leigong Mountain on the YunnanGuizhou Plateau of southwestern China,involved the collection of 35 surface soil samples from diverse vegetation communities along an elevational gradient ranging from 1210 to 1875 meters.The results reveal a close correspondence between modern pollen assemblages and vegetation zones.Principal Component Analysis(PCA)results indicate that pollen assemblages can effectively distinguish between subtropical montane evergreen broad-leaved forest(SEBF)and subtropical montane deciduous broadleaved forest(SDBF).However,both SEBF and SDBF show significant overlap with subtropical montane evergreen-deciduous broad-leaved mixed forest(SEMF).Detrended Correspondence Analysis(DCA)results clearly distinguish the three vegetation zones,and the first axis of DCA shows a significant positive correlation with elevation(p<0.01,R=0.48).Discriminant Analysis(DA)successfully assigns 94.4%of the modern pollen samples to their respective vegetation zones.Pollen taxa such as Impatiens,Astertype,and Rosaceae exhibit significant indicative capabilities for the SEBF zone,effectively distinguishing this vegetation zone from others.Pinus and Alnus display overrepresentation in the Leigong Mountain region,while Quercus(D,deciduous-type)and Poaceae exhibit high representation in the SEBF zone.In the SEBF zone,both pollen diversity and richness are the lowest.Our study reveals the complex relationship between the richness and diversity of pollen and vegetation.The diversity and richness of tree and shrub pollen are found to be lower than those of the corresponding plants.The pollen-vegetation relationship elucidated in this study serves as a critical reference for reconstructing ancient environments from fossil pollen retrieved in this region. 展开更多
关键词 Modern pollen assemblages Pollenvegetation relationship Pollen diversity and richness Leigong Mountain Southwestern China
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Understanding the concept of health literacy: A strategy to improve nursing practice
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作者 Cecilia Bukola BELLO Oladayo Damilola AKINWALE Mayowa Grace ELEMILE 《Journal of Integrative Nursing》 2024年第4期241-249,共9页
Health literacy(HL)is an effective approach for improved health status and measures the capacity of individuals to engage in health promotion and disease prevention activities as low HL constitutes a global problem in... Health literacy(HL)is an effective approach for improved health status and measures the capacity of individuals to engage in health promotion and disease prevention activities as low HL constitutes a global problem in health-care delivery.Nurses play a significant role in providing adequate information to the client and as such it becomes imperative for them to understand the concept of HL.Clinical approach of HL refers to ability to utilize literacy skills in relation to appointments,prescriptions,and instructions for self-management.Public health approach presents HL as means of empowering individuals to take control of their health and factors that influences health.HL is a hierarchy of skills that can be assessed and managed through health education and effective communication.Nurses’understanding of the concept of HL and strategies to reduce HL demands is crucial to delivery of effective nursing practice.This review will provide a clear understanding of the concept of HL which is essential for nurses to effectively educate patients and provide holistic care.More so,nurses will be able to assess literacy level of the patients,plan and develop better educational program tailored to patients’level of literacy.This could invariably improve patients’comprehension and adherence to treatment plans and overall health outcomes. 展开更多
关键词 Communication strategies health literacy concepts nurses nursing practice
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The Risk Role of Defeat on the Mental Health of College Students:A Moderated Mediation Effect of Academic Stress and Interpersonal Relationships
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作者 Ruiyang Han Tingting Xu +1 位作者 Yin Shi Wuyi Liu 《International Journal of Mental Health Promotion》 2024年第9期731-744,共14页
Background:College students face significant academic and physiological changes,making them more susceptible to psychological issues such as depression,self-injury,and suicidal ideation.Feelings of defeat can exacerba... Background:College students face significant academic and physiological changes,making them more susceptible to psychological issues such as depression,self-injury,and suicidal ideation.Feelings of defeat can exacerbate these risks by increasing academic stress.However,interpersonal relationships can moderate the impact of academic stress on students’mental health.Utilizing the presage–process–product model,this study aims to empirically investigate how feelings of defeat influence depression,self-injury,and suicidal ideation among college students.Additionally,it explores the mediating role of academic stress and the moderating role of various types of interpersonal relationships.Methods:A total of 1612 college students(750 females,862 males,mean age=19.64±0.62 years)were recruited through cluster sampling.Data were collected via offline questionnaires administered by a trained psychology teacher and a postgraduate student,ensuring high reliability with two examiners per class.Latent profile analysis(LPA)was used to examine the impact of defeat on mental health outcomes,while mediation analysis was conducted to assess the roles of academic stress and interpersonal relationships.Results:1.Defeat is identified as a significant risk factor for mental health issues among college students;2.Four distinct patterns of interpersonal relationships were identified:the interpersonal-relationship risk group,the father–child-relationship high-risk group,the general interpersonal-relationship group,and the superior interpersonal-relationship group;3.Academic stress partially mediates the relationship between defeat and mental health issues such as depression,self-injury,and suicidal ideation;4.Different interpersonal relationship models moderate the impact of academic stress on depression and suicidal ideation.Conclusion:Defeat is a significant risk factor for mental health problems in college students.Academic stress partially mediates the negative impact of defeat on mental health,while patterns of interpersonal relationships moderate this impact.Effective early prevention and intervention should focus on monitoring students’stress levels and fostering warm,positive parent–child relationships. 展开更多
关键词 Student mental health DEFEAT academic stress interpersonal relationships mediation test
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The Strange Relationship between the Momentum of a Photon Emitted from an Electron and the Momentum Acquired by the Electron
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作者 Koshun Suto 《Journal of Applied Mathematics and Physics》 2024年第7期2652-2664,共13页
In quantum mechanics, the energy of a hydrogen atom is minimized when the principal quantum number n is 1. However, the author has previously pointed out that the hydrogen atom has a state where n=0. An electron in th... In quantum mechanics, the energy of a hydrogen atom is minimized when the principal quantum number n is 1. However, the author has previously pointed out that the hydrogen atom has a state where n=0. An electron in the state where n=0has zero rest mass energy. However, a hydrogen atom has an energy level even lower than the n=0state. This is hard to accept from the standpoint of common sense. Thus, the author has previously pointed out that an electron at the energy level where n=0has zero energy because the positive energy mec2and negative energy −mec2cancel each other out. This paper elucidates the strange relationship between the momentum of a photon emitted when a hydrogen atom is formed by an electron with such characteristics, and the momentum acquired by the electron. 展开更多
关键词 Einstein’s Energy-Momentum relationship Energy-Momentum relationship in a Hydrogen Atom Momentum of a Photon Momentum of a Electron Negative Energy Specific to the Electron Dark Matter
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Value and Measures of Integrating Local Red Culture into the Ideological and Political Course of Environmental Disciplines under the OBE Concept
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作者 Xiong YAN Wenzhao LI +5 位作者 Shenwen CAI Bailian XIONG Liumei CHEN Junwei CHENG Qinghe WANG Leilei FAN 《Asian Agricultural Research》 2024年第2期40-42,共3页
Based on output-oriented education,the OBE(Outcome-Based Education)concept integrates local red culture into the ideological and political course of environmental disciplines,and is an important part of training appli... Based on output-oriented education,the OBE(Outcome-Based Education)concept integrates local red culture into the ideological and political course of environmental disciplines,and is an important part of training applied talents of environmental disciplines in the new era.This educational model makes an innovation on the traditional educational and teaching concepts and centers on students.This paper analyzes the value of integrating local red culture into the ideological and political course under the OBE concept,and puts forward an effective implementation path. 展开更多
关键词 OBE(Outcome-Based Education)concept Local red culture Environmental disciplines Ieological and political course
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Research on the strain gauge mounting scheme of track wheel force measurement system based on high-speed wheel/rail relationship test rig
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作者 Yuanwu Cai Bo Chen Chongyi Chang 《Railway Sciences》 2024年第4期503-513,共11页
Purpose-This paper aims to analyze the stress and strain distribution on the track wheel web surface and study the optimal strain gauge location for force measurement system of the track wheel.Design/methodology/appro... Purpose-This paper aims to analyze the stress and strain distribution on the track wheel web surface and study the optimal strain gauge location for force measurement system of the track wheel.Design/methodology/approach-Finite element method was employed to analyze the stress and strain distribution on the track wheel web surface under varying wheel-rail forces.Locations with minimal coupling interference between vertical and lateral forces were identified as suitable for strain gauge installation.Findings-The results show that due to the track wheel web’s unique curved shape and wheel-rail force loading mechanism,both tensile and compressive states exit on the surface of the web.When vertical force is applied,Mises stress and strain are relatively high near the inner radius of 710 mm and the outer radius of 1110mmof the web.Under lateral force,high Mises stress and strain are observed near the radius of 670mmon the inner and outer sides of the web.As the wheel-rail force application point shifts laterally toward the outer side,the Mises stress and strain near the inner radius of 710 mm of the web gradually decrease under vertical force while gradually increasing near the outer radius of 1110 mm of the web.Under lateral force,the Mises stress and strain on the surface of the web remain relatively unchanged regardless of the wheel-rail force application point.Based on the analysis of stress and strain on the surface of the web under different wheel-rail forces,the inner radius of 870 mm is recommended as the optimal mounting location of strain gauges for measuring vertical force,while the inner radius of 1143 mm is suitable for measuring lateral force.Originality/value-The research findings provide valuable insights for determining optimal strain gauge locations and designing an effective track wheel force measurement system. 展开更多
关键词 Track wheel High-speed wheel/rail relationship test rig Instrumented wheelset Strain gauge Finite element
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The Sustainable Development Pathway of the Biomedical Industry Based on Environmental,Social,and Governance(ESG)Concepts
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作者 Yangyan Chen 《Proceedings of Business and Economic Studies》 2024年第1期133-138,共6页
There is a growing global awareness of environmental,social,and governance(ESG)concerns.The biopharmaceutical industry is an important field that affects human health and well-being,and its sustainable development is ... There is a growing global awareness of environmental,social,and governance(ESG)concerns.The biopharmaceutical industry is an important field that affects human health and well-being,and its sustainable development is now the industry’s focus.Based on the current state of the green development of China’s biopharmaceutical industry,the article proposes suggestions and paths for promoting the industry to better fulfill its social responsibilities and protect the environment while pursuing economic benefits.By doing so,the industry can make a greater contribution to global public health and become an important factor in promoting human health and social prosperity. 展开更多
关键词 ESG concept Biomedical industry Sustainable development
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Progress in The Application of Nursing Care Based on ERAS Concept after Thoracolumbar Fracture Surgery
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作者 Ruigang Zhu Limiao Cui Rui Zhou 《Journal of Clinical and Nursing Research》 2024年第3期141-146,共6页
Thoracic spine fracture is a common orthopedic injury that is usually caused by external forces acting directly on or transmitted to the thoracic spine through other parts of the spine.Thoracic spine fractures can be ... Thoracic spine fracture is a common orthopedic injury that is usually caused by external forces acting directly on or transmitted to the thoracic spine through other parts of the spine.Thoracic spine fractures can be divided into two types:stable and unstable.An unstable fracture means that the relationship between the vertebral bodies is no longer stable,which may cause serious consequences such as spinal compression,nerve root compression,or spinal cord injury.Surgical treatment is often needed for patients with unstable fractures,nerve root compression,or spinal cord injury to restore stability and function to the thoracic spine.The probability of complications after thoracolumbar fracture surgery is high,which affects the outcome of surgical treatment.To improve postoperative rehabilitation outcomes,this article analyzed the value of nursing care based on the enhanced recovery after surgery(ERAS)concept for patients undergoing thoracolumbar fracture surgery. 展开更多
关键词 ERAS concept NURSING Thoracolumbar fracture surgery Application progress
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A Study on the Learning Progressions of Understanding the Core Concepts of Kinetic Energy in High School
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作者 Xuemei Cui Yue Zheng Yu Chen 《Journal of Contemporary Educational Research》 2024年第11期46-55,共10页
Learning progressions divide the logical system of a subject into ordered and continuously developing levels that are suitable for the cognitive development level of students,which plays an important role in understan... Learning progressions divide the logical system of a subject into ordered and continuously developing levels that are suitable for the cognitive development level of students,which plays an important role in understanding students’learning process.This paper focuses on the theme of“kinetic energy”in high school physics as the research object.Firstly,the concept map was used to represent the relationship between knowledge,and then five core concepts were selected based on the opinions of high school teachers.Secondly,the test tools were compiled and tested based on the relevant test questions.Finally,the paper analyzed the results based on the Rasch model,clarified students’cognitive development level of“kinetic energy”and constructed the learning progressions of“kinetic energy”based on the logical order of subject knowledge.The research provides theoretical and methodological support for the study of other subjects and learning progressions,and provides a valuable reference for high school teachers to effectively carry out the instruction of“kinetic energy.” 展开更多
关键词 Core concepts High school Kinetic energy Learning progressions
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Research on the Evaluation System of Community Daycare Center Planning and Implementation from the Perspective of Subject-Object Relationships
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作者 Tijin Gui 《Journal of Architectural Research and Development》 2024年第3期117-127,共11页
Through literature review,we found that evaluations of urban planning implementation often focus narrowly on either the subject(stakeholders)or the object(projects),while micro-level aspects such as site selection and... Through literature review,we found that evaluations of urban planning implementation often focus narrowly on either the subject(stakeholders)or the object(projects),while micro-level aspects such as site selection and construction are primarily considered within the context of planning implementation.There is insufficient research on the evaluation of implementation.Community daycare centers play a crucial role in the community home care model,yet there is relatively little research on their usage efficiency,satisfaction levels,and spatial evaluation of planning implementation.Based on the theoretical understanding of the human environment,including the subject,object,and their interactions,an evaluation system for the planning and implementation of community day care centers was constructed,incorporating subjective evaluation,objective evaluation,and comparative analysis. 展开更多
关键词 Subject-object relationship Daycare center Planning implementation Evaluation system
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Research on the Construction of a Comprehensive Teaching Case Library for Ergonomics under the OBE Concept
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作者 Haiyan Tang Wenting Ni 《Journal of Contemporary Educational Research》 2024年第10期29-34,共6页
In recent years,case-based teaching has become a hot spot in higher education reform,and the construction of case libraries has received increasing attention.The development of teaching case libraries not only promote... In recent years,case-based teaching has become a hot spot in higher education reform,and the construction of case libraries has received increasing attention.The development of teaching case libraries not only promotes changes in talent training models but also enhances teaching effectiveness.Taking the ergonomics course as an example,this paper explores the construction of a comprehensive teaching case library for ergonomics under the outcome-based education concept,providing a reference for future ergonomics teaching case library development. 展开更多
关键词 Outcome-based education concept ERGONOMICS Comprehensive teaching case library
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Research on the Teaching Design of Advanced Mathematics Courses Based on Outcome-Based Education Concept
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作者 Xinyu Huang 《Journal of Contemporary Educational Research》 2024年第6期148-154,共7页
This paper first analyzes the characteristics and current situation of the Advanced Mathematics course;secondly,it proposes a teaching model that integrates the outcome-based education(OBE)philosophy and blended teach... This paper first analyzes the characteristics and current situation of the Advanced Mathematics course;secondly,it proposes a teaching model that integrates the outcome-based education(OBE)philosophy and blended teaching method,reorganizing the teaching objectives,teaching content,and assessment evaluation process of the Advanced Mathematics course;lastly,through practice,it is proved that this approach can effectively improve students’mastery of course content,enhance students’ability to apply mathematical knowledge,and strengthen teaching effectiveness. 展开更多
关键词 Advanced Mathematics Outcome-based education concept Blended teaching method Online publication:July 3 2024
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Exploration on the Characteristics and Important Relationships of Xi Jinping's New Concept of Coordinated Economic Development
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作者 Huang Shaoqin Sun Peng Wu Hao 《Contemporary Social Sciences》 2017年第4期96-108,共13页
During the 18 th CPC National Congress, Xi Jinping raised a series of economic development thoughts, namely the five new concepts of development; innovative, coordinated, green, open and shared development, and put fo... During the 18 th CPC National Congress, Xi Jinping raised a series of economic development thoughts, namely the five new concepts of development; innovative, coordinated, green, open and shared development, and put forward a series of economic development thoughts including"people-centered"economic development. These are the new summations of the practice of socialism with Chinese characteristics, and the latest achievements in the theory of the political economics of socialism with Chinese characteristics."People-centered"is both the starting point and final purpose of coordinated economic development, an accurate mastery of social and economic development rules, and also the foundation and specific manifestation of coordinated development between people and society. People's subjectivity, coordinated inclusiveness and dialectics of development are the characteristics of coordinated economic development. Regional coordinated development, urbanrural coordinated development, industrial coordinated development, coordinated development of national defense and economic construction, supply and demand coordinated development, ecological coordinated development and interacted coordinated development of the global economy are the important relationships of coordinated economic development that we have to recognize and handle properly. 展开更多
关键词 Xi Jinping’s new concept of coordinated development new feature important relationships
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Application of Aesthetic Value of the World Modern Garden City and Exploration & Design of Its Artistic Conception——Using Chengdu City as a Case Study 被引量:1
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作者 孙大江 陈其兵 +2 位作者 胡庭兴 刘光立 孙大远 《Journal of Landscape Research》 2011年第1期1-3,6,共4页
This study explored the origin and development of modern garden city,by integrating concepts of world modern garden city and characteristics of Chengdu cultures,analyzed the application of its aesthetic value and the ... This study explored the origin and development of modern garden city,by integrating concepts of world modern garden city and characteristics of Chengdu cultures,analyzed the application of its aesthetic value and the design of its artistic conception.It was found that Chengdu City had high aesthetic value such as a large area of green spaces and unique recreational cultures,as well as a great potential of unifying idyllic images and natural cultures.To design Chengdu into a world modern garden city,the planning of its urban green space system should be taken as the foundation,"one group and three districts" as the construction system,urban folk cultures,logistics and traffic,information and other such networks as the support to achieve the "beauty of nature,social equity and urban-rural integration". 展开更多
关键词 GARDEN city AEStheTICS ARTISTIC conceptION DESIGN
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The Phylogenetic Relationships among Four Subspecies of the Genus Locusta Based on Sequences of Three Subunit of Cytochrome Oxidase 被引量:3
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作者 张道川 王健学 智永超 《Agricultural Science & Technology》 CAS 2011年第2期244-248,共5页
[Objective] The aim was to explore the phylogenetic relationships among four subspecies of the genus Locusta.[Method] The sequences of three subunits of cytochrome oxidase of Locusta migratoria tibetensis and Locusta ... [Objective] The aim was to explore the phylogenetic relationships among four subspecies of the genus Locusta.[Method] The sequences of three subunits of cytochrome oxidase of Locusta migratoria tibetensis and Locusta migratoria manilensis were amplified and sequenced(COⅠ 1 539 bp,COⅡ 684 bp,CO Ⅲ 792 bp,with the total of 3 015 bp).The corresponding sequenses of Locusta migratoria migratoria and Locusta migratoria migratorioides were obtained from GenBank and constructed a multiple alignment.Phylogenic trees of four subspecies of L.migratoria were constructed by Neighbor-Joining,Maximum-parsimony and Bayesian,respectively.[Result] The average content of A + T in three subunits of four subspecies was 69.57%;the third site of codon showed the highest A + T content,and the COⅠ had the highest A + T content(87.6%);The nucleotide substitution mainly occurred at the third site of codon,and the nucleotide replacement rate of CO Ⅱ was the highest.The second site of codon was conservative,so the replacement rate was in the range of 5.9%-15%.The start codon of COⅠ was CCG or ACG.Genetic distances among four subspecies were ranged from 0.001 to 0.076.The relationship between L.m.tibetensis and Locusta migratoria manilensis was the closest,followed by L.m.migratorioides and L.m.migratorioides,while the genetic distance between L.m.tibetensis and L.m.migratorioides was the largest.[Conclusion] The phylogenetic relationships among four subspecies of Locusta migratoria is L.m.tibetensis,L.m.manilensis,L.m.migratoria,L.m.migratorioides. 展开更多
关键词 LOCUSTA SUBSPECIES Phylogenetic relationship MITOCHONDRION Cytochrome oxidase
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Application of PCA and HCA to the Structure-Activity Relationship Study of Fluoroquinolones 被引量:2
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作者 李小红 张现周 +2 位作者 程新路 杨向东 朱遵略 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期143-148,共6页
Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analy... Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to reduce dimensionality and investigate in which variables should be more effective for classifying fluoroquinolones according to their degree of an-S.pneumoniae activity. The PCA results showed that the variables ELUMO, Q3, Q5, QA, logP, MR, VOL and △EHL of these compounds were responsible for the anti-S.pneumoniae activity. The HCA results were similar to those obtained with PCA.The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with antiS.pneumoniae activity. By using the chemometric results, 6 synthetic compounds were analyzed through the PCA and HCA and two of them are proposed as active molecules with anti-S.pneumoniae, which is consistent with the results of clinic experiments. 展开更多
关键词 Structure-activity relationship Density functional theory Principal component analysis Hierarchical cluster analysis
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Phylogenetic Relationships of Caragana(Fabaceae) by the Use of nrITS Sequences 被引量:2
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作者 康红梅 白娟 +1 位作者 陈康 王刚 《Agricultural Science & Technology》 CAS 2012年第1期36-39,共4页
[Objective] The aim was to explore the phylogenetic relationships of Cara- gana (Fabaceae) by the use of nrlTS sequences. [Method] Internal transcribed spac- er (ITS) sequences of nuclear ribosomal DNA (nrDNA) f... [Objective] The aim was to explore the phylogenetic relationships of Cara- gana (Fabaceae) by the use of nrlTS sequences. [Method] Internal transcribed spac- er (ITS) sequences of nuclear ribosomal DNA (nrDNA) from 29 taxa of Caragana species and seven close relatives (all belong to Astralinae (Adens) Benth) were used for phylogenetic analysis. [Result] Length of the entire ITS region ranges from 611 to 614 bp in Caragana species. The aligned sequences nrlTS of Caragana are 655 bp, and 170 sites are variable, with 107 phylogenetically informative sites. The phylogenetically informative sites are 16.3% of the total aligned sequences. The ITS sequences data are useful to resolve some relationships at lower taxonomic levels within Caragana. The Caragana Fabr. is not a monophyletic group with very close connection with Calophaca tianschanica. The ITS data revealed that the species of Sect. tragacanthoides were dispersed in MP tree or ME tree. Although the morphol- ogy of C. ordosica is similar to C. tibetica, the ITS results revealed an unexpectedly close relativeship to C. roborovskyi. The ITS data also indicate C. davazamcii, C. korshinskii, C. intermedia, and C. microphylla are different species. [Conclusion] ITS sequences have an important reference value in exploring the relationships of Cara- gana. 展开更多
关键词 Caragana Fabr. ITS sequence Phylogenetic relationships
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