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Commuting Space of Primary and Secondary Schools in the Context of Child Friendly Cities:A Case Study of Bajiao Street of Shijingshan District
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作者 LIU Ping PENG Li +2 位作者 WANG Zhihao CONG Jing DING Yuqi 《Journal of Landscape Research》 2024年第1期22-26,30,共6页
With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cit... With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cities,the commuting space of 11 primary and secondary schools in Bajiao Street is analyzed through literature analysis and field research methods.Firstly,the relevant literature on school commuting space is sorted out,and the characteristics of school commuting space are summarized,including transportation,landscape,culture,leisure,and security.Secondly,the characteristics of commuting space of primary and secondary schools in Bajiao Street are analyzed from three aspects:in front of the school gate,path space,and node space.This paper aims to provide reference and guidance for the future construction of children’s walking school commuting and promote the construction of a child friendly city. 展开更多
关键词 Child friendly cities School commuting space Bajiao Street primary and secondary schools
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The Application Value and Strategy of Red Music Culture in Ideological and Political Education in Primary and Secondary Schools
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作者 Jing Wang 《Journal of Contemporary Educational Research》 2024年第8期147-153,共7页
As an important carrier of red culture,red music culture carries the glorious history of revolution,construction,and reform led by the Communist Party of China(CPC),and has significant functional value in cultivating ... As an important carrier of red culture,red music culture carries the glorious history of revolution,construction,and reform led by the Communist Party of China(CPC),and has significant functional value in cultivating students’ideals,values,and cultural identity,as well as patriotic consciousness and national pride.However,the integration of red music culture into the ideological and political education of primary and secondary schools faces the dilemmas of low cultivation awareness,insufficient excavation of resources,and lack of optimization of atmosphere and field.In view of these problems,the strategies of enhancing cultivation awareness,excavating the resources in-depth,and creating a positive atmosphere and field provide new ideas and methods for ideological and political education in primary and secondary schools. 展开更多
关键词 Red music culture Ideological and political education primary and secondary schools Application value and strategy
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Exploring the Significance and Path of Interdisciplinary Integration of Art Education in Primary and Secondary Schools in the Era of Artificial Intelligence
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作者 Xin Guo Zixuan Li 《Journal of Contemporary Educational Research》 2023年第12期326-333,共8页
With the advent of the artificial intelligence(AI)era,there is a need to create a more flexible and humanistic educational ecosystem to adapt to the changes.Education needs to move from a unidirectional focus on skill... With the advent of the artificial intelligence(AI)era,there is a need to create a more flexible and humanistic educational ecosystem to adapt to the changes.Education needs to move from a unidirectional focus on skills to the cultivation of creative“whole people.”Due to the non-standardized evaluation system of the art discipline,its education has a unique advantage for the cultivation of students’creativity.At the same time,the interdisciplinary integration of fine arts points to the educational goals in the era of AI and the educational requirements for cultivating students’core qualities in China.Therefore,this paper analyzes the theoretical basis and developmental evolution of interdisciplinary integration,studies the significance of interdisciplinary integration in art education from the three levels of students,teaching,and disciplines,and explores four effective paths to realize interdisciplinary integration in art education in the era of AI.In this way,students can realize the contextualized analysis of knowledge,in-depth understanding of the content of the discipline,and accurate expression of the spiritual values embedded in art interdisciplinary learning.The ultimate goal is to cultivate students’ability to solve complex problems,promote the development of students’free personalities,and respond to the national education requirements. 展开更多
关键词 Artificial intelligence(AI) Art education primary and secondary art education INTERDISCIPLINARY Core literacy
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Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China
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作者 ZHU Haiqiang WANG Jinlong +2 位作者 TANG Junhu DING Zhaolong GONG Lu 《Journal of Arid Land》 SCIE CSCD 2024年第6期816-833,共18页
Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,i... Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China. 展开更多
关键词 net primary productivity(NPP) water yield soil conservation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model geographic detector Tianchi Bogda Peak Natural Reserve
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The Current Situation,Problems,and Improvement Path of Rule of Law Education in Primary and Secondary Schools in Chaoshan Area
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作者 Bin Li Zhou Yang Churui Chen 《Journal of Contemporary Educational Research》 2023年第12期308-315,共8页
Rule of law education in primary and secondary schools is an educational process to popularize legal knowledge,establish legal awareness,and cultivate the ability to respect,abide by,and use the law for the special gr... Rule of law education in primary and secondary schools is an educational process to popularize legal knowledge,establish legal awareness,and cultivate the ability to respect,abide by,and use the law for the special group of primary and secondary school students.The research found that rule of law education in primary and secondary schools in Chaoshan has yielded positive outcomes.However,there exist problems such as uneven synergy,incomplete inclusion of teachers and students,shortage of adequately trained professional teachers,and the need for enhanced organizational support.The relevance and effectiveness of rule of law education in primary and secondary schools will be enhanced by clarifying the target tasks,enhancing the effectiveness of the classroom,creating an atmosphere of the rule of law,and strengthening organizational support. 展开更多
关键词 EDUCATION Rule of law education YOUTH primary and secondary schools
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Artificial Intelligence Education in Primary and Secondary Schools from the Perspective of Thinking Quality
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作者 Min Peng Jingming Xie +1 位作者 Maohua Xiong Yunxiang Liu 《Journal of Contemporary Educational Research》 2023年第4期41-46,共6页
With the vigorous development of social economy in China,various advanced technologies and equipment have emerged,among which artificial intelligence(AI)has rapidly developed and achieved remarkable results when appli... With the vigorous development of social economy in China,various advanced technologies and equipment have emerged,among which artificial intelligence(AI)has rapidly developed and achieved remarkable results when applied to many fields.Therefore,leaders and teachers in primary and secondary schools should pay more attention to AI education and explore effective measures to optimize the effectiveness of this education.Among them,carrying out artificial intelligence education and teaching from the perspective of thinking quality,with an aim to improve students’technical ability and effectively cultivate their thinking skills,may improve students’learning efficiency and teachers’teaching efficiency.How to carry out AI education from the perspective of thinking quality is an important issue that teachers need to address urgently.Through in-depth research,we focus on this issue,in hope to benefit primary and secondary school teachers. 展开更多
关键词 Thinking quality primary and secondary schools Artificial intelligence Teaching path Online publication:April 25 2023
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Examining the Burden Reduction Policy for Primary and Secondary School Teachers in China:A Framework Analysis Centered on the Rational Selection of Institutional Doctrine
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作者 Haiying Xu 《Journal of Contemporary Educational Research》 2023年第12期244-247,共4页
The“burden reduction”policy aims to reduce the workload of primary and secondary school teachers to alleviate their burdens.While it has improved the quality of teachers,implementation challenges still exist.This st... The“burden reduction”policy aims to reduce the workload of primary and secondary school teachers to alleviate their burdens.While it has improved the quality of teachers,implementation challenges still exist.This study utilizes rational choice institutionalism and Ostrom’s institutional analysis and development framework to examine the policy.By considering the preferences of the Ministry of Education,local governments,schools,and teachers,it explores interactions and outcomes,identifies challenges,and provides policy suggestions. 展开更多
关键词 primary and secondary school teachers Reducing burden Rational selection institutional doctrine Institutional analysis and development framework
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Effects of Different Mulching Methods on Primary Substances and Secondary Substances of Lycium barbarum L.
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作者 周筠 康建宏 +2 位作者 杨涓 李锋 孙海霞 《Agricultural Science & Technology》 CAS 2010年第6期71-74,共4页
[Objective] The aim was to provide certain theoretical basis for stuides on the high yield and high quality cultivation of Lycium barbarum L..[Method] Under yield conditions,the accumulation of primary substances and ... [Objective] The aim was to provide certain theoretical basis for stuides on the high yield and high quality cultivation of Lycium barbarum L..[Method] Under yield conditions,the accumulation of primary substances and secondary substances of Lycium barbarum L.was studied under different mulching treatments.[Result] Different mulching methods all had a certain effects on the contents of main primary substances and main secondary substances in Lycium barbarum L.fruit.Among them,carbohydrates and flavonoids contents in Lycium barbarum L.were both obviously increased under straw-film mulching;carotenoid content was decreased relatively;hundred leaf weight,1 000-grain weight and yield of Lycium barbarum L.were increased to a certain extent,but there was no obvious effect on the shape of fruit.Besides,the yield of Lycium barbarum L.had no significant positive correlation with total carbohydrate and polysaccharide,almost had no correlation with flavonoids,and had no significant negative correlation with carotenoid.[Conclusion] The reasonable mulching could improve the yield and quality of Lycium barbarum L.. 展开更多
关键词 Lycium barbarum L. primary substances secondary substances Mulching materials
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Reliability analysis for vertical integration of protection,measurement,merge unit,and intelligent terminal device 被引量:1
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作者 Ying Li Weiquan Wang +3 位作者 Liang Zhang Zhujian Liang Zhenli Xu Yuansheng Liang 《Global Energy Interconnection》 EI CSCD 2023年第6期772-784,共13页
The reliability analysis of vertically integrated protection devices is crucial for designing International Electrotechnical Commission(IEC)61850-based substations.This paper presents the hardware architecture of a fo... The reliability analysis of vertically integrated protection devices is crucial for designing International Electrotechnical Commission(IEC)61850-based substations.This paper presents the hardware architecture of a four-inone vertically integrated device and the information transmission path of each function based on the functional information transmission chain of protection devices,measurement and control devices,merging units,and intelligent terminals.Additionally,a reliability analysis model of the protection device and its protection system is constructed using the fault tree analysis method while considering the characteristics of each module of the vertically integrated device.The stability probability of the protection system in each state is analyzed by combining the state-transfer equations of line and busbar protection with a Markov chain.Finally,the failure rate and availability of the protection device and its protection system are calculated under different ambient temperatures using a 110 kV intelligent substation as an example.The sensitivity of each device module is analyzed. 展开更多
关键词 Vertical integration of secondary system device Reliability of secondary system IEC 61850-based substation Relay protection
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Secondary steady-state and time-periodic flows from a basic flow with square array of odd number of vortices
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作者 Zhimin CHEN W.G.PRICE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第3期447-458,共12页
In a magnetohydrodynamic(MHD)driven fluid cell,a plane non-parallel flow in a square domain satisfying a free-slip boundary condition is examined.The energy dissipation of the flow is controlled by the viscosity and l... In a magnetohydrodynamic(MHD)driven fluid cell,a plane non-parallel flow in a square domain satisfying a free-slip boundary condition is examined.The energy dissipation of the flow is controlled by the viscosity and linear friction.The latter arises from the influence of the Hartmann bottom boundary layer in a three-dimensional(3D)MHD experiment in a square bottomed cell.The basic flow in this fluid system is a square eddy flow exhibiting a network of N~2 vortices rotating alternately in clockwise and anticlockwise directions.When N is odd,the instability of the flow gives rise to secondary steady-state flows and secondary time-periodic flows,exhibiting similar characteristics to those observed when N=3.For this reason,this study focuses on the instability of the square eddy flow of nine vortices.It is shown that there exist eight bi-critical values corresponding to the existence of eight neutral eigenfunction spaces.Especially,there exist non-real neutral eigenfunctions,which produce secondary time-periodic flows exhibiting vortices merging in an oscillatory manner.This Hopf bifurcation phenomenon has not been observed in earlier investigations. 展开更多
关键词 two-dimensional(2D)Navier-Stokes equation non-parallel square vortex flow primary bifurcation secondary steady-state flow secondary time-periodic flow
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Bifurcation control of nonlinear oscillator in primary and secondary resonance 被引量:8
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作者 李克安 萧寒 崔荣繁 《Journal of Central South University of Technology》 EI 2007年第6期826-831,共6页
A weakly nonlinear oscillator was modeled by a sort of differential equation, a saddle-node bifurcation was found in case of primary and secondary resonance. To control the jumping phenomena and the unstable region of... A weakly nonlinear oscillator was modeled by a sort of differential equation, a saddle-node bifurcation was found in case of primary and secondary resonance. To control the jumping phenomena and the unstable region of the nonlinear oscillator, feedback controllers were designed. Bifurcation control equations were obtained by using the multiple scales method. And through the numerical analysis, good controller could be obtained by changing the feedback control gain. Then a feasible way of further research of saddle-node bifurcation was provided. Finally, an example shows that the feedback control method applied to the hanging bridge system of gas turbine is doable. 展开更多
关键词 nonlinear oscillator saddle-node bifurcation feedback controller primary resonance secondary resonance gas turbine
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Percutaneous liver biopsy: retrospective study of primary and secondary hepatic lymphoma in twenty-one patients 被引量:2
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作者 Yan-Feng Bai Ji-Min Liu +3 位作者 Xiu-Ming Zhang Chao-Zhe Jiang Xiao Xu Shu-Sen Zheng 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2017年第1期58-64,共7页
BACKGROUND: Hepatic lymphoma (HL) is categorized as primary and secondary hepatic lymphoma (PHL and SHL). This disorder can present as hepatic mass or mass-like lesion. Chemotherapy often is the first line treatm... BACKGROUND: Hepatic lymphoma (HL) is categorized as primary and secondary hepatic lymphoma (PHL and SHL). This disorder can present as hepatic mass or mass-like lesion. Chemotherapy often is the first line treatment for patients with HL. Thus, an accurate pre-management histological diagnosis is essential to potentially improve clinical outcomes. The present study was to explore the prevalence of HL in ultrasound guided liver biopsies for hepatic mass or mass-like lesions, to investigate HL associated clinicopathological features, to raise the awareness of early recognition and proper diagnosis of this entity, and to assess specimen adequacy in needle core biopsy. METHODS: Twenty-one cases of HL were enrolled. Clinical and pathological characteristics were evaluated, quality of biopsies was assessed and pertinent literature was reviewed. RESULTS: HL was diagnosed in 0.94% of 2242 liver biopsy cases with ambiguous clinical presentation, laboratory tests and image studies. There were two cases of PHL (0.09%), and nineteen cases of SHL (0.85%). Histopathologically, diffuse large B-cell lymphoma was the most common type, followed by B-cell lymphoma not otherwise specified, T-ceU lymphoma, Hodgkin's lymphoma, and B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma. Additionally, three lym- phocytic infiltration patterns were documented microscopically. The nodular infiltration was the most common type. CONCLUSIONS: HL is a rare entity and histopathology along with ancillary tests remains the only way to make the diagnosis.Clinicians' awareness of this entity and early liver biopsy are essential in patient management. 展开更多
关键词 hepatic lymphoma primary and secondary percutaneous needle core biopsy
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Primary and secondary consolidation compression for saturated soil considering coupling effect of loading and heating 被引量:2
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作者 DENG Yue-bao MAO Wei-yun +1 位作者 KONG Gang-qiang HAN Yi-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第8期2514-2526,共13页
Geotechnical engineering that relates to the energy and environmental problem is receiving more and more attention worldwide.It is of great theoretical and practical value to study the properties of soil under thermal... Geotechnical engineering that relates to the energy and environmental problem is receiving more and more attention worldwide.It is of great theoretical and practical value to study the properties of soil under thermal mechanical coupling and its mathematical description.Firstly,based on the general function,a unified primary and secondary consolidation model of saturated soil considering heating temperature is deduced.Combining the existing research achievements,a practical model is obtained which comprehensively reflects the effective stress change,creep and heating effects.After that,a series of thermo-consolidation tests are carried out using a temperature controlled consolidation instrument to study the effects of effective stress,temperature and consolidation duration on saturated soils.The corresponding functional formulas and parameters are obtained thusly.On this basis,the calculation and analysis are carried out to check the reliability and applicability of the newly proposed model.The new model is simple and practical and the parameters are easy to be obtained.And it describes the main law of consolidation compression of saturated soils under the thermal mechanical coupling effect.Therefore,it is suggested for theoretical analysis of thermal geotechnical engineering problems. 展开更多
关键词 soft soil primary consolidation secondary consolidation temperature effect consolidation compression test
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Physical activity in primary and secondary prevention of cardiovascular disease:Overview updated 被引量:7
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作者 Alberto J Alves Joao L Viana +5 位作者 Suiane L Cavalcante Nórton L Oliveira JoséA Duarte Jorge Mota JoséOliveira Fernando Ribeiro 《World Journal of Cardiology》 2016年第10期575-583,共9页
Although the observed progress in the cardiovascular disease treatment, the incidence of new and recurrent coronary artery disease remains elevated and constitutes the leading cause of death in the developed countries... Although the observed progress in the cardiovascular disease treatment, the incidence of new and recurrent coronary artery disease remains elevated and constitutes the leading cause of death in the developed countries. Three-quarters of deaths due to cardiovascular diseases could be prevented with adequate changes in lifestyle, including increased daily physical activity. New evidence confirms that there is an inverse dose-response relationship between physical activity and cardiovascular disease and mortality risk. However, participation in moderate to vigorous physical activity may not fully attenuate the independent effect of sedentary activities on increased risk for cardiovascular diseases. Physical activity also plays an important role in secondary prevention of cardiovascular diseases by reducing the impact of the disease, slowing its progress and preventing recurrence. Nonetheless, most of eligible cardiovascular patients still do not benefit from secondary prevention/cardiac rehabilitation programs. The present review draws attention to the importance of physical activity in the primary and secondary prevention of cardiovascular diseases. It also addresses the mechanisms by which physical activity and regular exercise can improve cardiovascular health and reduce the burden of the disease. 展开更多
关键词 Physical activity primary prevention secondary prevention Cardiovascular disease Health care evaluation mechanisms
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Progress in clinical research on the integration of Chinese and Western medicines for treating primary liver cancer 被引量:3
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作者 Kaiqi Liu Hongliang Li +9 位作者 Jufeng Duan Xiaojing Chen Xiongjie Yu Xianhe Wang Ming Liu Bei Li Minglun Li Yibin Feng Xiaojun Cai Xuanbin Wang 《Journal of Traditional Chinese Medical Sciences》 2021年第3期173-185,共13页
Primary liver cancer(PLC) is one of the most common malignant tumors in China. PLC is characterized by insidious onset, rapid progress, poor quality of life, and short survival time. Notably, current treatment strateg... Primary liver cancer(PLC) is one of the most common malignant tumors in China. PLC is characterized by insidious onset, rapid progress, poor quality of life, and short survival time. Notably, current treatment strategies remain unsatisfactory. Traditional Chinese medicines(TCM) have been used to treat a variety of diseases, including liver diseases, for more than 2000 years. In this study, we performed a review of the use frequency and clinical efficacy of TCM in treating PLC. Relevant literature from January 1, 2009, to January 1, 2021 was retrieved from network databases of China National Knowledge Infrastructure(CNKI), Chongqing VIP, Wanfang, PubMed, and SinoMed. The most frequently used TCM and their efficacy in PLC treatment were summarized. Based on the inclusion and exclusion criteria, 33 articles were selected. Overall, the efficacy of the combination of TCM and Western medicines in the treatment of PLC was higher than that in the control groups(i.e. treatment with Western medicines alone)(65.11% vs.44.31%, P <.05). Among the 33 selected articles, 11 were investigated for TCM preparation(marketed drugs) and 22 for TCM formulas. In total, 102 types of TCM(single herbs) were used to treat PLC. The top five most frequently used TCM were Poria(14.71%), Astragali radix(13.73%), Atractylodis Macrocephalae Rhizoma(12.75%), Bupleuri radix(12.75%), and Glycyrrhizae radix et Rhizoma(11.76%). Of the 102 types of TCM, tonics were the most frequently used categories, followed by heat-clearing medicines, blood-invigorating medicines, and stasis-resolving medicines. Of 207 papers, 174(84.06%) could not be subjected to statistical analysis due to research quality. Further high-quality research on herb sources, formula components and dosage, toxicology, and ethics of TCM is necessary. In conclusion, TCM play a promising role in the treatment and management of PLC, although further investigations are warranted. 展开更多
关键词 Traditional Chinese medicines primary liver cancer Integrative medicine Clinical research
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Primary and secondary school mental health teachers in professional identity of intervention programs 被引量:1
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作者 Hao Lei Cheng Guo Yanling Liu 《Health》 2012年第12期1299-1304,共6页
To explore the impact of teacher training on the professional identity of primary and secondary school mental health teachers, this study conducted a half-month professional development training program to 54 primary ... To explore the impact of teacher training on the professional identity of primary and secondary school mental health teachers, this study conducted a half-month professional development training program to 54 primary and secondary school mental health teachers, and performed measurement on the professional identity of the teachers in the experimental group and the control group with “Teachers’ Professional Identity Questionnaire”. The result shows that after the training there is a significant improvement in the professional identity of the teachers in the experimental group, and the teachers’ scores on the four dimensions of profession identity: the sense of role, the professional behavioral tendency, the occupational values, and the sense of belonging, all increased significantly. This indicates that the curriculum intervention for the primary and secondary school mental health teachers could effectively improve the teachers’ professional identity. 展开更多
关键词 primary and secondary School MENTAL Health TEACHERS PRofESSIONAL IDENTITY CURRICULUM INTERVENTION
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Interactions of primary insult biomechanics and secondary cascades in spinal cord injury: implications for therapy 被引量:4
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作者 Michael B.Orr John C.Gensel 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第10期1618-1619,共2页
The complex and variable nature of traumatic spinal cord inju- ry (SCI) presents a unique challenge for translational research. SCI is not bound by any demographic nor is it limited to specific injury biomechanics.
关键词 SCI Interactions of primary insult biomechanics and secondary cascades in spinal cord injury:implications for therapy
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Roles of abscisic acid and gibberellins in maintaining primary and secondary dormancy of Korean pine seeds 被引量:1
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作者 Yuan Song Jiaojun Zhu Qiaoling Yan 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第6期2423-2434,共12页
Primary dormancy of seeds of Korean pine(Pinus koraiensis Sieb.et Zucc.)after dispersal in the autumn and the induction of secondary dormancy the fi rst summer following seed dispersal limit the regeneration of mixed ... Primary dormancy of seeds of Korean pine(Pinus koraiensis Sieb.et Zucc.)after dispersal in the autumn and the induction of secondary dormancy the fi rst summer following seed dispersal limit the regeneration of mixed broadleaved Korean pine forests in Northeast China.This study was to determine how changes in the levels of abscisic acid(ABA)and gibberellic acid(GA)maintain primary and secondary dormancy of Korean pine seeds under germination conditions.We transferred seeds with one of fi ve primary dormancy states or three secondary dormancy states to germination conditions and measured changes in the levels of ABA,GA 1+3(GA 1 and GA 3)and GA 4+7(GA 4 and GA 7)in the seed coat,megagametophyte and embryo during incubation.Seed coat ABA levels in primary dormant seeds(PDS)and ABA levels in various parts of secondary dormant seeds(SDS)gradually declined during incubation but were still higher than in seeds for which dormancy was progressively released.GA 4+7 and GA 1+3 levels in embryos greatly decreased 35%and 24%,respectively,during incubation of SDS,and thus,the ratio of ABA to GA 4+7 in embryos and megagametophytes signifi cantly increased.The ratio of ABA to GA 1+3 in various parts of SDS increased slightly during incubation.In contrast,in seeds for which secondary dormancy was already released,GA 4+7 and GA 1+3 levels in the embryo,GA 4+7/ABA ratio in the embryo and seed coat,and the GA 1+3/ABA in the embryo and megagametophyte signifi cantly increased during incubation.There was no trend in the changes in the levels of ABA,GA 4+7 or GA 1+3 in embryos and megagametophytes of PDS or the levels of GA 4+7 or GA 1+3 in megagametophytes of SDS during incubation.The results suggest that high ABA levels in the seed coat maintain primary dormancy of Korean pine seeds.Maintenance of secondary dormancy involves a reduction of GA 4+7,GA 1+3,GA 4+7/ABA,and GA 1+3/ABA and the retention of high ABA levels. 展开更多
关键词 Abscisic acid Gibberellic acid 4 and acid 7 Gibberellic acid 1 and acid 3 Korean pine primary dormancy secondary dormancy
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Thrust Characteristics Analysis of Long Primary Double Sided Linear Induction Machine with Plate and Novel Shuttle Secondary Structure
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作者 LIU Huijuan ZHANG Qian MA Jiefang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第5期693-702,共10页
The air-gap flux density formula and thrust expression of long primary double sided linear induction machine(DLIM)in the secondary motion reference frame are deduced by using the Maxwell equations firstly.Then,by anal... The air-gap flux density formula and thrust expression of long primary double sided linear induction machine(DLIM)in the secondary motion reference frame are deduced by using the Maxwell equations firstly.Then,by analyzing the factors that affect the thrust ripple in the thrust expression,a shuttle type secondary structure of long primary DLIMs is proposed,and its thrust performances of the machine with different shuttle size combinations are simulated and compared with that of plate secondary long primary DLIM.Comparison results show that the new secondary structure can suppress the thrust ripple and improve the stability of system acceleration. 展开更多
关键词 LINEAR induction machine LONG primary RIPPLE end effect SHUTTLE secondary
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Detection the Spectrum Holes in the Primary Bandwidth of the Cognitive Radio Systems in Presence Noise and Attenuation
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作者 Ahmed S. Kadhim Haider M. AlSabbagh 《International Journal of Communications, Network and System Sciences》 2012年第10期684-690,共7页
Cognitive Radio (CR) and Dynamic Spectrum Access (DSA) represent two complementary developments that will refashion the world of wireless communication. In order to investigate the roles of knowledge representation an... Cognitive Radio (CR) and Dynamic Spectrum Access (DSA) represent two complementary developments that will refashion the world of wireless communication. In order to investigate the roles of knowledge representation and reasoning technologies in this domain, we have developed an experimental cognitive radio simulation environment. That is, a conventional radio when operating in a particular communications mode always follows the same procedure and either succeeds or fails at a given task. A cognitive radio, by contrast, can use knowledge of radio technology and policy, representations of goals, and other contextual parameters to reason about a failed attempt to satisfy a goal and attempt alternate courses of action depending upon the circumstances. 展开更多
关键词 COGNITIVE Radio (CR) Power Spectral Density (PSD) primary USER (PU) secondary USER (SU)
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