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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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Prevalence of vegetation browning in China’s drylands under climate change 被引量:1
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作者 Li Fu Guolong Zhang +3 位作者 Jianping Huang Ming Peng Lei Ding Dongliang Han 《Geography and Sustainability》 CSCD 2024年第3期405-414,共10页
Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning ... Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning of vegetation remain scarce.In this study,we utilized the normalized difference vegetation index(NDVI)as an indicator of vegetation to investigate the trends of vegetation greening and browning(monotonic,interruption,and reversal)through the breaks for the additive season and trend(BFAST)method across China’s drylands from 1982 to 2022.It also reveals the impacts of ecological restoration programs(ERPs)and climate change on these vegetation trends.We find that the vegetation displays an obvious pattern of east-greening and west-browning in China’s drylands.Greening trends mainly exhibits monotonic greening(29.8%)and greening with setback(36.8%),whereas browning shows a greening to browning reversal(19.2%).The increase rate of greening to browning reversal is 0.0342/yr,which is apparently greater than that of greening with setback,0.0078/yr.This research highlights that,under the background of widespread vegetation greening,vegetation browning is pro-gressively increasing due to the effects of climate change.Furthermore,the ERPs have significantly increased vegetation coverage,with the increase rate in 2000-2022 being twice as much as that of 1982-1999 in reveg-etation regions.Vegetation browning in southwestern Qingzang Plateau is primarily driven by adverse climatic factors and anthropogenic disturbances,which offset the efforts of ERPs. 展开更多
关键词 chinas drylands Ecological restoration programs Climate change Greening to browning reversal BFAsT
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Changes of China’s Status in the Global System and Its Influencing Factors:A Multiple Contact Networks Perspective
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作者 LIU Jian LIU Jibin +2 位作者 YANG Qingshan CAI Sikai LIU Jie 《Chinese Geographical Science》 SCIE CSCD 2024年第2期265-279,共15页
Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on cou... Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on country comparisons or institutional en-vironment.In today’s networked era in which the global economy,trade,personnel,and information are closely connected,studies on China’s global position and its status changes and influencing factors in multiple contact networks are still insufficient.In this study,from the perspective of diverse global contact networks,we constructed economic,cultural,and political influence indices to explore the changes and influencing factors on China’s status in the global system from 2005 to 2018.The results show that during the study period,China’s global influence in the fields of economic ties,cultural exchanges,and political contacts increased significantly,but its influ-ence in the fields of cultural exchanges and political contacts lagged far economic ties.The pattern of China’s economic influence on various economies around the world has shown a transformation from an‘upright pyramid’to an‘inverted pyramid’structure.The proportion of these economies in low-influence zones has decreased from more than 60%in 2005 to less than 20%in 2018.China’s cultural and political influence on various economies around the world has increased significantly;however,for the former,the percentage of high-influence areas is still less than 20%,whereas for the latter the percentage of these economies in medium-and high-influence areas is still less than 50%.Analyses such as a scatter plot matrix show that geographical proximity,economic globalization,close cooperation with developing countries,and a proactive and peaceful foreign policy are important factors in improving China’s status in the diverse global network system. 展开更多
关键词 global system economic ties cultural exchanges political contacts multiple contact networks chinas status
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Understanding the Global Identification with China’s Stories: A Cross-Cultural Perspective
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作者 Fu Chun Deng Da 《Contemporary Social Sciences》 2024年第1期46-57,共12页
Cross-cultural storytelling is a primary way for humankind to seek mutual recognition of value orientations between cultures,which facilitates the ability to jointly address the problems of human existence in the cont... Cross-cultural storytelling is a primary way for humankind to seek mutual recognition of value orientations between cultures,which facilitates the ability to jointly address the problems of human existence in the context of globalization.In this study,we conducted an interview survey of 6,130 respondents who were college students or graduates from 107 countries.The results show that there were a number of cross-cultural values embodied in China’s stories seen by the respondents as part of a common vision for the future of humankind and widely identified guidance on collaborative responses to global challenges.These cross-cultural values are common prosperity,ecological harmony,individual-collective integration,the urgency of global peace,as well as respect for multicultural and indigenous development paths. 展开更多
关键词 chinas stories global identification cross-cultural communication
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Spatio-temporal Variation Characteristics of Extreme Climate Events and Their Teleconnections to Large-scale Ocean-atmospheric Circulation Patterns in Huaihe River Basin,China During 1959–2019
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作者 YAO Tian ZHAO Qiang +6 位作者 WU Chuanhao HU Xiaonong XIA Chuan'an WANG Xuan SANG Guoqiang LIU Jian WANG Haijun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期118-134,共17页
Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of... Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of 40 meteorological stations and nine monthly large-scale ocean-atmospheric circulation indices data during 1959–2019,we present an assessment of the spatial and temporal variations of extreme temperature and precipitation events in the HRB using nine extreme climate indices,and analyze the teleconnection relationship between extreme climate indices and large-scale ocean-atmospheric circulation indices.The results show that warm extreme indices show a significant(P < 0.05) increasing trend,while cold extreme indices(except for cold spell duration) and diurnal temperature range(DTR) show a significant decreasing trend.Furthermore,all extreme temperature indices show significant mutations during 1959-2019.Spatially,a stronger warming trend occurs in eastern HRB than western HRB,while maximum 5-d precipitation(Rx5day) and rainstorm days(R25) show an increasing trend in the southern,central,and northwestern regions of HRB.Arctic oscillation(AO),Atlantic multidecadal oscillation(AMO),and East Atlantic/Western Russia(EA/WR) have a stronger correlation with extreme climate indices compared to other circulation indices.AO and AMO(EA/WR) exhibit a significant(P < 0.05) negative(positive)correlation with frost days and diurnal temperature range.Extreme warm events are strongly correlated with the variability of AMO and EA/WR in most parts of HRB,while extreme cold events are closely related to the variability of AO and AMO in eastern HRB.In contrast,AMO,AO,and EA/WR show limited impacts on extreme precipitation events in most parts of HRB. 展开更多
关键词 extreme climate indices sen’s slope variation mutation test atmospheric circulation indices Pearson’s correlation analysis Huaihe River Basin(HRB) china
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Spatial Differentiation,Typological Structure,and Influencing Factors of A-grade Scenic Spots in China
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作者 YANG Yuanyuan YAO Yao 《Journal of Resources and Ecology》 CSCD 2024年第5期1209-1218,共10页
Tourism scenic spots serve as direct attractions for tourists and crucial drivers for the transformation and upgrading of the tourism industry,so they play an irreplaceable role in the development of the tourism secto... Tourism scenic spots serve as direct attractions for tourists and crucial drivers for the transformation and upgrading of the tourism industry,so they play an irreplaceable role in the development of the tourism sector.The quantity and grades of A-grade scenic spots are the mainstay of competition in various tourism markets,and their spatial layout is very important for the development of regional tourism.Using 11970 A-grade scenic spots in China as the research sample,and methods such as the Nearest Neighbor Index Method,Kernel Density Estimation Method,and Grid Dimension Method,the spatial distribution,typological structure,and influencing factors of A-grade tourist attractions were analyzed to identify the main natural,economic,and social factors influencing the spatiotemporal pattern of A-grade scenic spots.The results indicated that China’s A-grade scenic spots exhibit clustering characteristics in their spatial distribution.The kernel density center shows a spatial pattern of“multiple cores,with secondary cores surrounding,and a gradual decrease”.The spatial structure is fractal and complex,with significant regional differences and a notable scale-free range.The types of tourist destinations and products exhibit distinct regional features,with a higher concentration of scenic spots in the regions in South China and East China,which are characterized by favorable natural and economic conditions and convenient transportation.A-grade scenic spots are densely distributed around the Beijing-Tianjin-Hebei region and the eastern regions such as Shanghai,Zhejiang,and Jiangsu provinces.Analyzing the spatial distribution characteristics of A-grade scenic spots in China contributes to our understanding of the complexity of scenic spot layout and spatial connections,which provides a basis for optimizing the layout of tourism development within regions,the rational allocation of resources,enhancing the quality and efficiency of the tourism industry,and promoting sustained and healthy regional economic development.It is conducive to the strategic work of tourism development and rural revitalization in China,and serves as a reference for decision-making. 展开更多
关键词 chinas A-grade scenic spots spatial differentiation types of scenic spots scenic features rural revitalization
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Evolution and Governance of the Structure of Marine Economic Networks in China’s Coastal Areas: Based on Sea-related A-share Listed Companies
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作者 LI Bo CAO Gai 《Chinese Geographical Science》 SCIE CSCD 2024年第5期899-916,共18页
Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linka... Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to emerge.The construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic development.Employing data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its governance.The following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is significant.On this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing bodies.By clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy. 展开更多
关键词 marine economic network sea-related A-share listed companies social network analysis(sNA) network governance chinas coastal areas
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Pioneering a New Realm of Human Rights Civilization in the Chinese Path to Modernization——An Overview of the Symposium on“The Chinese Path to Modernization and the Promotion of Free and Comprehensive Human Development”
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作者 王新怡 黄安杰 QIAN chuijun(Translated) 《The Journal of Human Rights》 2024年第2期476-481,共6页
On October 14,2023,a symposium themed“The Chinese Path to Modernization and the Promotion of Free and Comprehensive Human Development”was held in Changchun,Jilin Province,China.More than fifty experts,scholars,and r... On October 14,2023,a symposium themed“The Chinese Path to Modernization and the Promotion of Free and Comprehensive Human Development”was held in Changchun,Jilin Province,China.More than fifty experts,scholars,and researchers from national institutions and universities engaged in discussions and exchanges on human rights on the Chinese path to modernization,including the path,practice,knowledge systems,and civilization forms of human rights.This symposium played a significant role in advancing the construction of the disciplinary system,academic system,and discourse system of human rights in China. 展开更多
关键词 Chinese path to modernization Chinese human rights civilization chinas indigenous human rights knowledge system free and comprehensive human development
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Entrepreneurial Spirit for China in the New Era and Strategies for Cultivation
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作者 Xu Yuanhua He Jun +1 位作者 Sun Zao Li Xiaoke 《China Economist》 2024年第5期48-59,共12页
What type of entrepreneurial spirit is needed for China’s new era,and how can we unlock its innovation potential?Answers to these questions will unleash vital forces to drive China’s high-quality economic developmen... What type of entrepreneurial spirit is needed for China’s new era,and how can we unlock its innovation potential?Answers to these questions will unleash vital forces to drive China’s high-quality economic development.After reviewing the theories,dimensions,features,and limitations of the entrepreneurial spirit in the Western context,we concluded that the entrepreneurial spirit in China’s new era,which is characterized by patriotism,innovation,trustworthiness,adherence to the law,fulfillment of social responsibilities,and a global horizon,has overcome the limitations that come with self-interested entrepreneurship in the context of Western economics.This is a major step forward in the development of theories on entrepreneurial spirit.In the development context of the new era,this paper argues that the entrepreneurial spirit should become an important force at the individual level to implement the new development concept,foster the new development paradigm,and promote high-quality development in the new stage.This paper provides answers to the question of what type of entrepreneurial spirit China’s new era requires.Finally,this paper presents basic strategies for cultivating entrepreneurial spirit in the context of China’s new era,emphasizing the importance to promote the healthy growth of young entrepreneurs,ensure their business autonomy,develop a multi-tiered capital market,implement the factor market reforms,improve the business climate,and accelerate the digital transition. 展开更多
关键词 Context of chinas new era context of Western economics entrepreneurial spirit high-quality development cultivation strategy
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GDI and GSI: China’s New Propositions for Global Governance
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作者 Ouyang Xiangying 《China Economist》 2024年第5期107-116,共10页
In the post-pandemic era,the global economic and security landscapes are fraught with complexities and uncertainties.Among them,four risk flashpoints merit attention:Certain countries are raising interest rates to sub... In the post-pandemic era,the global economic and security landscapes are fraught with complexities and uncertainties.Among them,four risk flashpoints merit attention:Certain countries are raising interest rates to subdue inflation,despite their already high levels of debt;the bulk commodities market is experiencing volatility,leading to global turbulence and change;trade protectionism is at the forefront of major-power rivalry in political and economic spheres;and regional security crises are compounding international tensions.Behind those flashpoints are contradictions that obstruct world peace and progress,including development imbalances,governance gaps,and structural tensions in global security.In the face of uncertainties,it is crucial for China to seize strategic opportunities and transform crises into favorable situations.China has launched the Global Development Initiative(GDI)and the Global Security Initiative(GSI)to contribute to global prosperity and security.The two initiatives demonstrate China’s commitment to addressing global deficits in peace,development,security,and governance. 展开更多
关键词 Global Development Initiative(GDI) Global security Initiative(GsI) chinas approach to global governance Ukraine crisis china-Russia relationship
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Transitivity Analysis of the Energy in China’s New Era
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作者 SHAN Ting WANG Yu 《Journal of Literature and Art Studies》 2024年第2期170-176,共7页
At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environme... At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environment has become a global issue that cannot be ignored in today’s era.Therefore,from the perspective of the ecological philosophy of Diversity&Harmony as well as Interaction&Co-existence,this paper will conduct ecological discourse analysis on the Energy in China’s New Era based on the transitivity system of systemic-functional grammar,and use the Corpus analysis software UAM Corpus Tool 3.3x to label and make statistics on the transitivity system,aiming to explore the distribution characteristics of the transitivity system in this white paper.Through the transitivity analysis of the white paper,this study helps readers to have a deeper understanding of the positive significance contained in the white paper.To a certain extent,it enables readers at home and abroad to understand China’s stance on energy issues and the positive image of China in energy ecology.It also awaken readers’awareness of environmental protection and acquire good habits of resource conservation to be in harmony between human and nature for sustainable development. 展开更多
关键词 TRANsITIVITY Ecological discourse analysis Energy in chinas new era
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Historical review and reflections on the participation of acupuncture and moxibustion in the treatment of epidemics in the People’s Republic of China (from 1950 until now)
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作者 Xiong Xiao 《History & Philosophy of Medicine》 2024年第3期1-5,共5页
Since the establishment of the People’s Republic of China, both the Communist Party and the government have placed great emphasis on the advancement of traditional Chinese medicine. Acupuncture and moxibustion have b... Since the establishment of the People’s Republic of China, both the Communist Party and the government have placed great emphasis on the advancement of traditional Chinese medicine. Acupuncture and moxibustion have been actively involved in combating major epidemics such as malaria, schistosomiasis, and COVID-19. This article conducts a historical review of these three significant cases to elucidate how the acupuncture community has effectively utilized its unique advantages and characteristics through theoretical discussions, clinical practices, experimental research, as well as receiving administrative leadership and political support from the Communist Party of China and government. We provide an objective evaluation of their effectiveness while summarizing historical experiences to serve as a reference for future utilization of acupuncture and moxibustion therapy in epidemic relief efforts. Additionally, propose four suggestions: strengthening Party leadership and enhancing political support;timely summarization of experiences to establish programs and systems;deepening scientific research by integrating experimental findings with clinical practice;focusing on public awareness campaigns and education to solidify grassroots foundations. 展开更多
关键词 acupuncture and moxibustion the People’s Republic of china EPIDEMICs MALARIA sCHIsTOsOMIAsIs COVID-19
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Analysis of New Senior English for China Student’s Book 1
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作者 Xia Qian 《语言与文化研究》 2024年第4期128-132,共5页
This article will firstly discuss the context overview of English teaching and learning in China. Under thiscircumstance, a problematic element will be examined of the New Senior English for China Student’s Book 1 an... This article will firstly discuss the context overview of English teaching and learning in China. Under thiscircumstance, a problematic element will be examined of the New Senior English for China Student’s Book 1 and critical appraisal ofhow this element relates to other elements of curriculum development will be analyzed. The recommended changes and demonstrationmechanisms for evaluating the changes are put forward in the last two parts. 展开更多
关键词 New senior English for china student’s Book 1 Assessment Critical appraisal Curriculum development CHANGEs
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Contribution and Modern Public Debt:On the Nature of Patriotic Public Debt in the Late Qing Dynasty and the Early Republic of China
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作者 Chuanrong Huang 《Sociology Study》 2023年第6期309-314,共6页
There are different opinions about the first modern domestic debt in China.The theorists judge whether a certain public debt has modernity according to whether it has modern public debt form,ignoring the inconsistency... There are different opinions about the first modern domestic debt in China.The theorists judge whether a certain public debt has modernity according to whether it has modern public debt form,ignoring the inconsistency between form and content,institutional provisions and actual implementation.The modern nature of public debt must have both the form and content of modern public debt.Based on the analysis of the issuing background,system design,collection and repayment of patriotic bonds in the late Qing Dynasty and the early Republic of China,it is considered that the part of patriotic bonds subscribed by the Qing royal family is still the nature of donation and return,while the part subscribed by ordinary businessmen and people in the early Republic of China has a modern nature.The dual nature of patriotic bonds is closely related to the social background when the bonds are issued. 展开更多
关键词 donation and return modern nature patriotic bonds late Qing Dynasty and early Republic of china
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Struggling Between Tradition and Modernity: A Feminist Interpretation of Yu Opera China Women
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作者 LIU Kang 《Sino-US English Teaching》 2019年第7期315-320,共6页
Yu Opera China Women (some translated it into Our Company)(2000) has been well received by audiences for its simple folk description, vivid characters, touching story lines, stunning stage backgrounds, and exquisite s... Yu Opera China Women (some translated it into Our Company)(2000) has been well received by audiences for its simple folk description, vivid characters, touching story lines, stunning stage backgrounds, and exquisite stage performances. The opera describes a story of Xiangxiang and Huanhuan, mother-in-law and daughter-in-law, two generations of women in the reform and opening up years in the 20th century in China. These Chinese women try to break the shackles of fate, with the strength to overcome hardships, work hard to gain wealth, and be brave to pursue true love, so it has a strong sense of feminism. However, rooted in the deep traditional Chinese culture, Xiangxiang and Huanhuan are always struggling between tradition and modernity and they make difficult choices along with the awakening of women’s consciousness. 展开更多
关键词 china WOMEN FEMINIsM TRADITION sTRUGGLE modernity
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The Rise of Women’s Education and the Modernity of East Asia:Focusing on the Education of“Virtuous Wives and Worthy Mothers”in China and Japan
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作者 HE Wei 《Cultural and Religious Studies》 2022年第9期500-516,共17页
This year marks the 50th anniversary of the normalization of diplomatic relations between China and Japan.Looking back on the past and forward to the future,we realize modernity has become a critical issue that not on... This year marks the 50th anniversary of the normalization of diplomatic relations between China and Japan.Looking back on the past and forward to the future,we realize modernity has become a critical issue that not only China and Japan,but the whole East Asian region should pay attention to.China and Japan are both within the“Circle of Confucius Culture”and are both modern latecomer countries.As they were coerced by western countries to enter the modern age,they shared multiple common features.An exploration of the two countries’respective rising of modern women’s education is an important path to discuss the reconstruction of gender and an important method of the course of the embodiment of east-Asian women into modernization drives.With regards to conclusion,entering the modern age,Chinese and Japanese intellectuals reshaped the female gender in terms of interpersonal relationship,value system,and knowledge structure by advocating the idea of“virtuous wives and worthy mothers”education.In the concept of virtuous wives and worthy mothers in East Asia,the Confucian ethics of“docility and virtue”is the soul,and modern scientific knowledge serves this core value.On the other hand,in the course of localization in China and Japan,this imported concept from the West has encountered a completely different historical fate. 展开更多
关键词 women’s education modernity china JAPAN virtuous wives and worthy mothers
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Pollen Assemblage Features of Modern Water Samples from the Shiyang River Drainage, Arid Region of China 被引量:7
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作者 朱艳 陈发虎 +2 位作者 程波 张家武 David B.MADSEN 《Acta Botanica Sinica》 CSCD 2002年第3期367-372,共6页
Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and Badain Jaran deserts, Northwest China was carried out to examine the river's capacity to c... Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and Badain Jaran deserts, Northwest China was carried out to examine the river's capacity to carry pollen and spores, and to assess the contribution of the water-borne pollen to pollen assemblages in lake sediments at the end of the river system. Results indicate the pollen assemblages in water samples consist of both local and upland pollen. Percentages of upland pollen reach 30% - 60%, and pollen assemblages in water samples do not indicate the nature of local vegetation at the sampling sites. Fluvial currents have the capacity to transport large quantities of pollen long distances, and the contribution of this fluvial transported pollen is relatively high, For example, percentages of Picea Dietr. pollen in water samples at sampling sites 130 km and 145 km away from Picea forests reach 16.5% and 7.7%, respectively. Fluvial pollen transport occurs primarily during flood periods, and pollen concentrations from the flood samples are 17.1 - 12.5 times those from normal fluvial flow. Reservoirs affect pollen transportation since pollen is deposited at reservoir inlets and pollen concentrations are much reduced at reservoir outlets. Human activity can thus change natural features of pollen transportation and deposition. The main factors influencing pollen concentrations and assemblages are sampling time, sampling location, and rainfall intensity. 展开更多
关键词 pollen analysis modern river water shiyang River arid region of china
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基于程函面波成像的华北克拉通岩石圈三维高分辨率S波速度结构研究
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作者 钟世军 吴建平 +2 位作者 司政亚 朱红彬 王薇 《地震学报》 CSCD 北大核心 2024年第4期578-599,共22页
利用“中国地震科学台阵探测”项目Ⅱ期和Ⅲ期的流动地震台站以及中国区域地震台网中的部分固定台站的观测资料,采用程函面波成像方法获得了华北克拉通及周边区域10—120 s周期的瑞雷面波相速度分布和高分辨率的三维S波速度结构,并基于... 利用“中国地震科学台阵探测”项目Ⅱ期和Ⅲ期的流动地震台站以及中国区域地震台网中的部分固定台站的观测资料,采用程函面波成像方法获得了华北克拉通及周边区域10—120 s周期的瑞雷面波相速度分布和高分辨率的三维S波速度结构,并基于该速度模型估算了岩石圈厚度分布。结果显示,华北克拉通内部岩石圈厚度除了存在“西厚东薄”的一级分布特征外,还存在一些更小尺度的差异,包括鄂尔多斯地块内部岩石圈“南厚北薄”、鄂尔多斯地块周缘断陷带岩石圈显著的不均匀减薄以及燕山构造带与其南侧华北平原之间的显著差异等。山西断陷带北部与南部地区上地幔浅部(<100 km)存在不同程度的低速异常,它们被中部的高速异常区所分隔。在150 km以下深度从太行山南缘向北至山西断陷北缘存在一条NNE向展布的显著低速异常带,表明上地幔浅部南北部的低速异常在深部相连。结合已有的其它成像结果,我们推测这些低速异常起源于更深处(>200 km),并与由太平洋俯冲板块的滞留脱水导致的上地幔热物质上涌和小尺度地幔对流等密切相关。燕山构造带与华北平原的岩石圈结构存在明显差异,前者遭受的岩石圈破坏改造程度明显弱于后者,张家口—渤海地震带位于这两种不同壳幔结构的过渡带,地震活动较强,我们认为深部结构和热作用的显著差异,以及青藏高原远场挤压效应的共同作用是导致该区地震活动较强的主要原因。 展开更多
关键词 华北克拉通 程函面波成像 s 波速度 低速异常 岩石圈厚度 显著差异
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Modernism in Europe and in China,taking Lukcs Brecht and Lu Xun as examples
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作者 高继海 《外文研究》 2014年第1期69-73,107,共6页
Lukcs argues that modernist writers are preoccupied with formal experiment and fails to see their literary merits.Brecht criticizes Lukcs for not paying attention to class struggle and rejects the kind of formal u... Lukcs argues that modernist writers are preoccupied with formal experiment and fails to see their literary merits.Brecht criticizes Lukcs for not paying attention to class struggle and rejects the kind of formal unity admired by Lukcs.Lu Xun,like Brecht,insisted on the class nature of literature,emphasizing the fighting function of literature in a time when the nation was faced with Japanese invasion. 展开更多
关键词 modernIsM EUROPE china
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东北地区土地覆被格局变化模拟:基于CLUE-S和Markov-CA模型的对比分析 被引量:2
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作者 王端睿 毛德华 +2 位作者 王宗明 相恒星 冯凯东 《地理科学》 CSCD 北大核心 2024年第2期329-339,共11页
研究以遥感解译的东北地区2000年、2010年、2015年的土地覆被变化为基础,充分考虑自然和社会因素对土地覆被变化的影响,分别通过CLUE-S模型和Markov-CA模型对东北地区2015年和2030年土地覆被格局进行模拟,研究结果表明:通过与遥感解译的... 研究以遥感解译的东北地区2000年、2010年、2015年的土地覆被变化为基础,充分考虑自然和社会因素对土地覆被变化的影响,分别通过CLUE-S模型和Markov-CA模型对东北地区2015年和2030年土地覆被格局进行模拟,研究结果表明:通过与遥感解译的2015年实际土地覆被类型数据对比验证,CLUE-S模型和Markov-CA模型模拟结果的总体Kappa指数分别为0.9700和0.9649,结果表明2种模型的模拟结果较为理想,CLUE-S模型的模拟精度较Markov-CA模型更高。2015—2030年东北地区草地、耕地、湿地、其他用地和水体面积呈现下降趋势,林地、人工表面面积呈现增加趋势,人地关系越发紧张。东北地区作为生态环境相对脆弱的区域需警惕不可持续的土地覆被变化,需权衡生态保护、粮食增加与基础设施建设的用地需求和协调发展。 展开更多
关键词 CLUE-s模型 Markov-CA模型 土地利用/覆被变化 空间模拟 东北地区
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