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Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling 被引量:3
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作者 Shuang-Biao Han Chao-Han Xiang +3 位作者 Xin Du Lin-Feng Xie Jie Huang Cheng-Shan Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期741-751,共11页
The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantl... The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas. 展开更多
关键词 Gas compositions Stable isotopes Gas origins Hydrogen gas Songliao Basin
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Insights into the Origins of Solar-Assisted Electrochemical Water Oxidation in Allotropic Co_(5.47)N/CON Heterojunctions
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作者 Sirui Liu Qiong Gao +8 位作者 Bo Geng Lili Wu Zhikun Xu Xinzhi Ma Shijie Liu Boquan Li Mingyi Zhang Lirong Zhang Xitian Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第5期234-243,共10页
Solar irradiation can efficiently promote the kinetics of the oxygen evolution reaction(OER)during water splitting,where heterojunction catalysts exhibit excellent photoresponsive properties.However,insights into the ... Solar irradiation can efficiently promote the kinetics of the oxygen evolution reaction(OER)during water splitting,where heterojunction catalysts exhibit excellent photoresponsive properties.However,insights into the origins of photoassisted OER catalysis remain unclear,especially the interfaced promotion under convergent solar irradiation(CSI).Herein,novel allotropic Co_(5.47)N/CoN heterojunctions were synthesized,and corresponding OER mechanisms under CSI were comprehensively uncovered from physical and chemical aspects using the in situ Raman technique and electrochemical cyclic voltammetry method.Our results provide a unique mechanism where high-energy UV light promotes the Co^(3+/4+)conversion process in addition to the ordinary photoelectric effect excitation of the Co^(2+)material.Importantly,visible light under CSI can produce a photothermal effect for Co^(2+)excitation and Co^(3+/4+)conversion,which promotes the OER significantly more than the usual photoelectric effect.As a result,Co_(5.47)N/CoN(containing 28%CoN)obtained 317.9%OER enhancement,which provides a pathway for constructing excellent OER catalysts. 展开更多
关键词 chemical origins in situ Raman OER photothermal effect physical origins
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Scientists Clarify the Origins of Lunar Metallic Iron
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《Bulletin of the Chinese Academy of Sciences》 2024年第2期97-98,共2页
Metallic iron nanoparticles(npFe0)are widespread on the Moon,and their accumulation changes the optical spectra of the lunar surface over time.How the surface color changes largely depends on the size of npFe0:smaller... Metallic iron nanoparticles(npFe0)are widespread on the Moon,and their accumulation changes the optical spectra of the lunar surface over time.How the surface color changes largely depends on the size of npFe0:smaller npFe0 reddens the reflectance spectra,while larger npFe0 causes darkening.The resultant color variations greatly complicate remote sensing studies,posing long-term puzzles to astronomers. 展开更多
关键词 origin SURFACE reflectance
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Analysis of Volatile Constituents in Lonicera japonica Thunb. from Different Origins by GC-MS 被引量:12
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作者 杜成智 冯旭 +2 位作者 王卉 吴玲 李盼 《Agricultural Science & Technology》 CAS 2015年第5期1081-1083,1087,共4页
[Objective] This study aimed to analyze the volatile constituents in Lonicera japonica Thunb. from different origins. [Method] HP-5MS capillary columns were used and column temperature was controlled by a program. MS ... [Objective] This study aimed to analyze the volatile constituents in Lonicera japonica Thunb. from different origins. [Method] HP-5MS capillary columns were used and column temperature was controlled by a program. MS analysis was performed with EI and quadruple mass analyzer. The volatile constituents in L. japonica Thunb. were identified by NIST02 and Wiley275 libraries, and their relative contents were determined with chromatographic peak area normalization method. [Result] According to GC-MS total ion-current chromatograms, 35 volatile constituents were identified in L. japonica Thunb. from Guangxi Zhuang Autonomous Region, mainly including methyl linolenate, n-hexadecanoic acid and ζ-muurolene; 18 volatile constituents were identified in L. japonica Thunb. from Hunan Province, mainly including n-hexadecanoic acid, linoleic acid and α-curcumene. [Conclusion] Main volatile constituents in L. japonica Thunb. from two different origins varied significantly. 展开更多
关键词 Lonicera japonica Thunb. Volatile constituents GC-MS Different origins
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RAPD Analysis of Litchi chinensis Sonn.from Different Origins of China 被引量:2
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作者 梅志强 李春红 龚舒 《Agricultural Science & Technology》 CAS 2012年第1期64-67,共4页
[Objective] To lay the foundation for the classification and breeding of Litchi (Litchi chinensis Sonn.) through RAPD (Random Amplification Polymorphic DNA) analysis of the Litchi cultivars with different origins.... [Objective] To lay the foundation for the classification and breeding of Litchi (Litchi chinensis Sonn.) through RAPD (Random Amplification Polymorphic DNA) analysis of the Litchi cultivars with different origins. [Method] 5 Litchi cultivars from Sichuan, Guangxi, Guangdong, Fujian and Hainan were used as experimental materials to extract genomic DNA by modified CTAB method. Twenty primers with well reproducibility were randomly selected to conduct RAPD amplification to analyze the polymorphism and genetic relationship of the five cultivars. [Result] The polymor- phism of the five Litchi cultivars was 61%, with the similarity coefficient of 0.571 4- 0.803 6. The similarity coefficient of those from Guangdong and Guangxi was the largest of 0.803 6, and from Sichuan and Hainan was the lowest of 0.571 4. The resolution and production of RAPD was significantly improved by appropriately pro- longing the ramp time from annealing to extension to 0.3℃/s. [Conclusion] This study provided theoretical basis for the classification and breeding of Litchi. 展开更多
关键词 RAPD RAMP LITCHI origin
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Sexism in the English Language: Its Origins, Representation and Desexism 被引量:1
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作者 马珂 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S3期166-170,共5页
Sexism in the English Language is the reflector of a social sexism. The thesis is not only to discuss phenomena of sexism in English in terms of morphology, syntax and semantics, but also to focus on the origins and p... Sexism in the English Language is the reflector of a social sexism. The thesis is not only to discuss phenomena of sexism in English in terms of morphology, syntax and semantics, but also to focus on the origins and point out the ways of desexism. 展开更多
关键词 SEXISM the ENGLISH LANGUAGE origin Desexism
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Detecting the Origins of Moisture over Southeast China:Seasonal Variation and Heavy Rainfall 被引量:5
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作者 Xiuzhen LI Wen ZHOU Yongqin David CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第3期319-329,共11页
To examine the ability of the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to detect the origins and paths of moisture supplied to Southeast China, trajectories of air particles released o... To examine the ability of the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to detect the origins and paths of moisture supplied to Southeast China, trajectories of air particles released over Southeast China were traced backward during 1 April 2012 to 31 March 2013 and three typical regional persistent heavy rainfall events. The HYSPLIT model provides more insightful information than water vapor flux. Analysis of the specific humidity along the trajectories revealed the origins of moisture and their contributions to the moisture supply in Southeast China. In the boreal summer half year, four key moisture transport paths from the eastern Indian Ocean, central Indian Ocean, South China Sea (SCS), and western North Pacific (WNP) contribute 10%, 20%, 31%, and 16% of the moisture to Southeast China, respectively. In the winter half year, the contributions of the paths from the WNP and North China double. Examination of heavy rainfall events showed that under tropical storm conditions, all moisture transport routines are rotated cyclonically before reaching Southeast China. The invasion of cold air can trigger heavy rainfall in both the summer and winter half years but plays different roles: it does not contribute to the moisture supply but plays a key role in converging and uplifting the moisture in the summer half year, while it supplies a great amount of moisture in the winter half year as it absorbs abundant moisture in crossing the WNE 展开更多
关键词 moisture origin Southeast China HYSPLIT seasonal variation heavy rainfall
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Origins and pathways of the subsurface and intermediate water masses of the Indonesian Throughflow derived from historical and Argo data 被引量:4
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作者 ZHANG Yanhui YU Xiaolin WANG Fan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第4期17-25,共9页
On the basis of Argo data and historic temperature/salinity data from the World Ocean Database 2001 ( WOD01 ), origins and spreading pathways of the subsurface and intermediate water masses in the Indonesian Through... On the basis of Argo data and historic temperature/salinity data from the World Ocean Database 2001 ( WOD01 ), origins and spreading pathways of the subsurface and intermediate water masses in the Indonesian Throughflow (ITF) region were discussed by analyzing distributions of salinity on representative isopyenal layers. Results were shown that, subsurface water mostly comes from the North Pacific Ocean while the intermediate water originates from both the North and South Pacific Ocean, even possibly from the Indian Ocean. Spreading through the Sulawesi Sea, the Makassar Strait, and file Flores Sea, the North Pacific subsurface water and the North Pacific Intermediate water dominate the western part of the Indonesian Archipelago. Furthermore as the depth increases, the features of the North Pacific sourced water masses become more obvious. In the eastern part of the waters, high sa- linity South Pacific subsurface water is blocked by a strong salinity front between Halmahera and New Guinea. Intermediate water in the eastern interior region owns salinity higher than the North Pacific intermediate water and the antarctic intermediate water ( AAIW), possibly coming from the vertical mixing between subsurface water and the AAIW from the Pacific Ocean, and possibly coming from the northward extending of the AAIW from the Indian Ocean as well. 展开更多
关键词 Indonesian Throughflow subsurface water intermediate water origin PATHWAY
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Analysis on Genetic Similarity of Japonica Rice Variety from Different Origins of Geography in the World 被引量:5
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作者 SHU Ai-ping Kim Jong hwan +5 位作者 ZHANG San-yuan CAO Gui-lan NAN Zhong-hao Lee Kyu seong LU Qin HAN Long-zhi 《Agricultural Sciences in China》 CAS CSCD 2009年第5期513-520,共8页
The genetic similarity and genetic difference among improved japonica rice varieties from different countries (or regions and organizations) were detected. The aim is to provide genetic basis to the breeding of japo... The genetic similarity and genetic difference among improved japonica rice varieties from different countries (or regions and organizations) were detected. The aim is to provide genetic basis to the breeding of japonica rice varieties. The genetic similarity and cluster of 313 improved japonica varieties from 20 countries (or regions and organizations) were analyzed using the SSR marker. With 34 SSR primers which were polymorphic and uniformly distributed in rice genome, totally 198 alleles were detected among these improved varieties with the average number of alleles per pair of primers of 5.8235. RM320, RM531, RM1, RM21, and RM336 located more alleles, which were 16, 13, 12, 10, and 10 respectively. RM320, RM336, RM286, RM531, and RM21 showed higher genetic diversity indexes, which were 2.3668, 2.0041, 1.9684, 1.9508, and 1.7203, respectively. The genetic similarity for improved japonica varieties among different countries (or regions and organizations) were ranged from 0.279 to 0.918, and the mean value was 0.653. The rice varieties from countries whose latitude and geography position were all nearer were clustered together with higher genetic similarity indexes. The rice varieties from countries who had more different latitude and far geography position were clustered separately with lower genetic similarity indexes. The results indicated the genetic similarity indexes among improved japonica varieties had a close relationship with the geographical position, especially with the latitude. 展开更多
关键词 japonica rice genetic similarity geography origin LATITUDE SSR marker
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Origins and transports of the low-salinity coastal water in the southwestern Yellow Sea 被引量:5
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作者 ZHU Ping WU Hui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第4期1-11,共11页
In the southwestern Yellow Sea there is a low-salinity and turbid coastal water,the Subei Coastal Water(SCW).The origins of freshwater contents and thus the dissolved terrigenous nutrients in the SCW have been debat... In the southwestern Yellow Sea there is a low-salinity and turbid coastal water,the Subei Coastal Water(SCW).The origins of freshwater contents and thus the dissolved terrigenous nutrients in the SCW have been debated for decades.In this study,we used a well-validated numerical model to quantify the contributions of multiple rivers,i.e.,the Changjiang River in the south and the multiple Subei local rivers(SLRs) in the north,in forming this yearround low-salinity coastal water.It is found that the freshwater contents in the SCW is dominated by the Changjiang River south of 33.5°N,by the SLRs north of 34.5°N,and by both sources in 33.5°–34.5°N.Overall,the Changjiang River contributes ~70% in the dry season and ~80% in the wet season of the total freshwater contents in the SCW,respectively.Dynamics driving the Changjiang River Plume to flow northward is the tidal residual current,which can even overwhelm the wind effects in winter seasons.The residual currents turn offshore near the Old Yellow River Delta(OYRD) by the collision of the two tidal wave systems,which transport the freshwater from both sources into the interior Yellow Sea.Water age experiments show that it takes 50–150 d for the Changjiang River Plume to reach the SCW in the spring and summer seasons,thus there is a 2-month lag between the maximum freshwater content in SCW and the peak Changjiang River discharge.In the winter and autumn seasons,the low salinity in inner SCW is the remnant Changjiang River diluted water arrived in the previous seasons. 展开更多
关键词 Subei Coastal Water origins river plume numerical modeling
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Zoonotic origins of human coronavirus 2019(HCoV-19/SARS-CoV-2):why is this work important? 被引量:13
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作者 Gary Wong Yu-Hai Bi +3 位作者 Qi-Hui Wang Xin-Wen Chen Zhi-Gang Zhang Yong-Gang Yao 《Zoological Research》 SCIE CAS CSCD 2020年第3期213-219,共7页
The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by infection with human coronavirus 2019 (HCoV-19/SARS-CoV-2/2019-nCoV), is a global threat to the human population. Here, we briefly summarize the a... The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by infection with human coronavirus 2019 (HCoV-19/SARS-CoV-2/2019-nCoV), is a global threat to the human population. Here, we briefly summarize the available data for the zoonotic origins of HCoV-19, with reference to the other two epidemics of highly virulent coronaviruses, SARSCoV and MERS-CoV, which cause severe pneumonia in humans. We propose to intensify future efforts for tracing the origins of HCoV-19, which is a very important scientific question for the control and prevention of the pandemic. 展开更多
关键词 origin why is this work important HCoV-19/SARS-CoV-2 Zoonotic origins of human coronavirus 2019
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Origin可视化在物理教学中的应用——以斜抛运动为例
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作者 黄兴勇 刘汉平 陈容飞 《科技风》 2024年第35期92-94,共3页
基于高中物理教学现状,剖析现在高中物理教学存在的问题。通过对斜抛运动的理论分析,推导出水平射程和竖直射程。利用Origin的可视化功能,可视化显示斜抛运动的运动轨迹。根据可视化结果,深入分析斜抛运动的运动规律,探究出水平射程和... 基于高中物理教学现状,剖析现在高中物理教学存在的问题。通过对斜抛运动的理论分析,推导出水平射程和竖直射程。利用Origin的可视化功能,可视化显示斜抛运动的运动轨迹。根据可视化结果,深入分析斜抛运动的运动规律,探究出水平射程和竖直射程的内涵关系。 展开更多
关键词 斜抛运动 origin 可视化
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Cultural Differences between English and Chinese on Idioms Origins
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作者 郭丽杰 《科技信息》 2010年第18期130-131,共2页
Different people from different cultures may have different understandings of the same sentence because they know little about the target cultures. While the ultimate aim of English teaching as a foreign language is t... Different people from different cultures may have different understandings of the same sentence because they know little about the target cultures. While the ultimate aim of English teaching as a foreign language is to cultivate students' competence to apply English correctly, fluently, and appropriately in cross-cultural communication. Idioms, a part of language, are the essence of culture in every country. Using language in such communication, we often come across some idioms with distinctive cultural characteristics, so it is a very important and complicated thing for us to understand and use these idioms correctly. Therefore, in this paper, we will discuss the idioms reflecting the differences of Chinese and Western cultures in various levels with many lively, important, and interesting examples of idioms. 展开更多
关键词 英语教学 教学方法 英语习语 阅读
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Functional origins of the vertebrate cerebellum from a sensory processing antecedent 被引量:1
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作者 John MONTGOMERY David BODZNICK 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第3期277-284,共8页
The structure of the cerebellar cortex is remarkably similar across vertebrate phylogeny. It is well developed in basaljawed fishes, such as sharks and rays with many of the same cell types and organizational features... The structure of the cerebellar cortex is remarkably similar across vertebrate phylogeny. It is well developed in basaljawed fishes, such as sharks and rays with many of the same cell types and organizational features found in other vertebrategroups, including mammals. In particular, the lattice-like organization of cerebellar cortex (with a molecular layer of parallel fibres,interneurons, spiny Purkinje cell dendrites, and climbing fires) is a common defining characteristic. In addition to the cerebellarcortex, fishes and aquatic amphibians have a variety of cerebellum-like structures in the dorso-lateral wall of the hindbrain.These structures are adjacent to, and in part, contiguous with, the cerebellum. They derive their cerebellum-like name from thepresence of a molecular layer of parallel fibers and inhibitory interneurons, which has striking organizational similarities to themolecular layer of the cerebellar cortex. However, these structures also have characteristics which differ from the cerebellum. Forexample, cerebellum-like structures do not have climbing fibres, and they are clearly sensory. They receive direct afferent inputfrom peripheral sensory receptors and relay their outputs to midbrain sensory areas. As a consequence of this close sensory association,and the ability to characterise their signal processing in a behaviourally relevant context, good progress has been made indetermining the fundamental processing algorithm in cerebellar-like structures. In particular, we have come to understand thecontribution to signal processing made by the molecular layer, which provides an adaptive filter to cancel self-generated noise inelectrosensory and lateral line systems. Given the fundamental similarities of the molecular layer across these structures, coupledwith evidence that cerebellum-like structures may have been the evolutionary antecedent of the cerebellum, we address the question:do both share the same functional algorithm? [Current Zoology 56 (3): 277-284, 2010]. 展开更多
关键词 origin VERTEBRATE CEREBELLUM
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Using Sr isotopes to trace the geographic origins of Chinese mitten crabs 被引量:7
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作者 Hao-Ming Yin Fang Huang +1 位作者 Jun Shen Hui-Min Yu 《Acta Geochimica》 EI CAS CSCD 2020年第3期326-336,共11页
Identifying the geographic origins of Chinese mitten crabs is important for food safety and fair market competition.In this study,we used strontium(Sr) isotopes as a tool to trace the geographic origins of Chinese mit... Identifying the geographic origins of Chinese mitten crabs is important for food safety and fair market competition.In this study,we used strontium(Sr) isotopes as a tool to trace the geographic origins of Chinese mitten crabs.Chinese mitten crabs,water,and different types of crab feed were collected from four different lakes for Sr isotope analyses.The results showed that the Sr isotope compositions of the different parts from one single crab were consistent within error,indicating that any piece of a crab could be used to represent the Sr isotope characteristics of the whole crab.The Sr isotope compositions of Chinese mitten crabs from the same lake were consistent within the analytical error,and the values were similar to the Sr isotope composition of the water from the same lake.However,the Sr isotope compositions of water and crabs from different lakes are significantly different.Therefore,the Sr isotope compositions of Chinese mitten crabs are mainly controlled by lake water composition,while the impact of feed is limited.This study provides an effective method for tracing the geographic origins of Chinese mitten crabs. 展开更多
关键词 Chinese mitten crab LAKES Sr isotopes Geographic origin
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Spatiotemporal switching signals for cancer stem cell activation in pediatric origins of adulthood cancer:Towards a watch-and-wait lifetime strategy for cancer treatment 被引量:1
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作者 Shengwen Calvin Li Mustafa H Kabeer 《World Journal of Stem Cells》 SCIE CAS 2018年第2期15-22,共8页
Pediatric origin of cancer stem cell hypothesis holds great promise and potential in adult cancer treatment, however; the road to innovation is full of obstacles as there are plenty of questions left unanswered. First... Pediatric origin of cancer stem cell hypothesis holds great promise and potential in adult cancer treatment, however; the road to innovation is full of obstacles as there are plenty of questions left unanswered. First, the key question is to characterize the nature of such stem cells (concept). Second, the quantitative imaging of pediatric stem cells should be implemented(technology). Conceptually, pediatric stem cell origins of adult cancer are based on the notion that plasticity in early life developmental programming evolves local environments to cancer. Technologically, such imaging in children is lacking as all imaging is designed for adult patients. We postulate that the need for quantitative imaging to measure space-time changes of plasticity in early life developmental programming in children may trigger research and development of the imaging technology. Such quantitative imaging of pediatric origin of adulthood cancer will help develop a spatiotemporal monitoring system to determine cancer initiation and progression. Clinical validation of such speculative hypothesis-that cancer originates in a pediatric environment-will help implement a wait-andwatch strategy for cancer treatment. 展开更多
关键词 PEDIATRIC origins of ADULT CANCER Imaging of single cells
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Origins and evolution of plant diversity in the Hengduan Mountains, China 被引量:47
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作者 Hang Sun Jianwen Zhang +1 位作者 Tao Deng David E. Boufford 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第4期161-166,共6页
1.Introduction The Hengduan Mountains region(HDM)in southwest China,one of the earth's 34 biodiversity hotspots,is characterized by its unique geology,dramatic topography,a climate where snow and below freezing te... 1.Introduction The Hengduan Mountains region(HDM)in southwest China,one of the earth's 34 biodiversity hotspots,is characterized by its unique geology,dramatic topography,a climate where snow and below freezing temperatures can occur on any day of the year,by its location at elevations averaging between(1400e)2000 and4500(e5300)meters above sea level(m a.s.l.),and by one of 展开更多
关键词 origins and evolution of plant diversity in the Hengduan Mountains China HDM QTP
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Similar Faults Different Endings--A Comparison between the Origins of Tess's and Hester's Tragedy
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作者 肖彬 《广西大学学报(哲学社会科学版)》 2009年第S2期206-207,共2页
Hester Prynne and Tess Durbeyfield were two eminent female figures in the world by Thomas Hardy and Nathaniel Hawthone.Although the two female leading characters were in different time and place,their tragic experienc... Hester Prynne and Tess Durbeyfield were two eminent female figures in the world by Thomas Hardy and Nathaniel Hawthone.Although the two female leading characters were in different time and place,their tragic experiences were almost the same.However,they were separated in the end.From the comparison of their personalities and the social situation they involved in,we would try to explore the origins of their similarity and ending by this article with the aim of alerting the world. 展开更多
关键词 HESTER TESS origin Difference of PERSONALITY Social Factor
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Petrology of ureilites from Grove Mountains,Antarctica:Constraints on the origins 被引量:1
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作者 缪秉魁 林杨挺 +4 位作者 王道德 沈文杰 王葆华 胡森 刘焘 《Chinese Journal of Polar Science》 2009年第2期151-165,共15页
Ureilites are a common group of achondrites with a high abundance of carbon. They probably have a genetic relationship with chondrites, hence provide an insight into origin and evdution of terrestrial planets. A new m... Ureilites are a common group of achondrites with a high abundance of carbon. They probably have a genetic relationship with chondrites, hence provide an insight into origin and evdution of terrestrial planets. A new meteorite-rich region, Grove Mountains ( GRV), was found by the Chinese Antarctic Research Expedition, with discovery of 9834 meteorites. Of 2433 meteorites classified, 9 ureilites have been identified. In this paper, we report petrography of 6 of these ureilites. Four ureilites contain graphite and exhibit triangle conjunction and common reduced margins of divine. GRV 052382 probably experienced heavy shock metamorphism followed by fast coding, as indicated by mosaic texture or fine-grained granular texture of olivine. GRV 022931 was highly reduced of these ureilites, with olivine as isolated grains in abundant carbonaceous matrix. All 9 ureilites are monomict, and arc classified into subtype II (with medium FeO content, Fa15-18 ) and subtype I (with high FeO content, Fa 〉 18) based on compositions of the cores of olivine. The diverse mineral compositions and petrography of these ureilites suggest that they are not paired and reveal a multi-event history of the parent body. Partial melting of the parent body produced carbon-rich magma, followed by crystallization of graphite and silicates. Later, graphite was partially inverted to diamond by shock events. Reburial of the shocked debris experienced various degree of thermal metamorphism. Finally, these rocks were excavated from the parent asteroid and ejected into Earth-cross orbit by another impact event. 展开更多
关键词 ureilites Grove Mountains origin achondrltes Antarctica.
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Overpressure origins and evolution in deep-buried strata:A case study of the Jurassic Formation,central Junggar Basin,western China 被引量:1
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作者 Qiao-Chu Wang Dong-Xia Chen +7 位作者 Xian-Zhi Gao Mei-Jun Li Xue-Bin Shi Fu-Wei Wang Si-Yuan Chang Dong-Sheng Yao Sha Li Shu-Min Chen 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1429-1445,共17页
Overpressure is significant to the exploration and exploitation of petroleum due to its influence on hydrocarbon accumulation and drilling strategies.The deep-burial hydrocarbon reservoirs of Jurassic strata in the ce... Overpressure is significant to the exploration and exploitation of petroleum due to its influence on hydrocarbon accumulation and drilling strategies.The deep-burial hydrocarbon reservoirs of Jurassic strata in the central Junggar Basin are characterized by intensive overpressure,whose origins are complex and still unclear.In this study,Bowers'method and sonic velocity-density crossplot method based on well logging data were used as a combination for overpressure judgements in geophysics.Furthermore,the corresponding geological processes were analysed in quality and quantity to provide a rational comprehension of the overpressure origins and the model of overpressure evolution and hy-drocarbon accumulation processes.The results showed that hydrocarbon generation in the Jurassic source rocks led to overpressure in the mudstones,while hydrocarbon generation in Permian source rocks led to overpressure in the sandstone reservoirs in Jurassic strata by vertical pressure transfer.The burial and thermal history indicated that the aquathermal effect of pore fluids by temperature increase in deep strata is also an important origin of overpressure,while disequilibrium compaction may not be the dominant cause for the overpressure in deep-buried strata.Furthermore,the continuous tectonic compression in both the north-south and west-east trends from the Jurassic period to the present may also have enhanced the overpressure in deep strata.Meanwhile,the developed faults formed by intensive tectonic compression led to pressure transfer from source rocks to the Jurassic reservoirs.Overpressured geofluids with hydrocarbons migrated to sandstone reservoirs and aggravated the over-pressure in the Jurassic strata.To conclude,the intensive overpressure in the central Junggar Basin is attributed to the combination of multiple mechanisms,including hydrocarbon generation,the aqua-thermal effect,tectonic compression and pressure transfer.Furthermore,the developed overpressure indicated hydrocarbon migration and accumulation processes and the potential of oil and gas reservoirs in deeply buried strata.We hope this study will provide a systematic research concept for overpressure origin analysis and provide guidance for petroleum exploration and exploitation in deep-buried strata. 展开更多
关键词 origin of overpressure Hydrocarbon generation Tectonic compression Overpressure transfer Junggar Basin
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