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Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H
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作者 Jianzhao Yin Yuhong Chao +2 位作者 Haoyu Yin Hongyun Shi Shoupu Xiang 《Acta Geochimica》 EI CAS CSCD 2024年第2期385-398,共14页
By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)... By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly magmatic.According to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will be.In other words,mantle-derived solutions can have extremely low hydrogen isotope values.This means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the deposit.The formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma. 展开更多
关键词 Carbon oxygen and hydrogen isotopes origin Independent tellurium deposit the Qinghai–Xizang Plateau
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Unroofing Technique for Anomalous Origin of the Left Coronary Artery from the Right Sinus of Valsalva: Report of a Case
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作者 Keisuke Morimoto Futoshi Kobayashi +2 位作者 Hiromu Horie Yuki Sakaguchi Einosuke Mizuta 《World Journal of Cardiovascular Surgery》 2024年第6期69-77,共9页
Anomalous origin of the left coronary artery (AOLCA) from the right sinus of Valsalva constitutes a rare congenital coronary artery anomaly. Patients with an anomalous left main coronary artery face a significantly hi... Anomalous origin of the left coronary artery (AOLCA) from the right sinus of Valsalva constitutes a rare congenital coronary artery anomaly. Patients with an anomalous left main coronary artery face a significantly higher risk of sudden cardiac death compared to those with an anomalous right coronary artery. The anomalous coronary artery traversing between the ascending aorta and the pulmonary artery markedly heightens the risk of myocardial ischemia, arrhythmia, and sudden death. Symptomatic patients often exhibit a longer intramural course of the coronary artery, which may necessitate earlier intervention or influence the choice of surgical repair method. Surgical intervention is advocated for patients with this anomaly, even in the absence of symptoms. For anomalous aortic origin of a coronary artery from the opposite sinus of Valsalva with an intramural course, coronary unroofing is the preferred revascularization procedure. This report presents a case of AOLCA originating from the right sinus of Valsalva, treated surgically using the unroofing technique for the aortic intramural segment of the anomalous coronary artery traversing between the great vessels. The unroofing technique is recommended for treating AOLCA with an extensive intramural course that does not involve the commissure. 展开更多
关键词 Unroofing Technique Anomaly of Coronary Artery Anomalous origin of Left Coronary Artery
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Gibbon vocal communication provides insights into the origin and evolution of human music and language
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作者 Zi-Di Wang Hai-Gang Ma Peng-Fei Fan 《Zoological Research(Diversity and Conservation)》 2024年第2期130-132,共3页
Humans across cultures convey feelings and thoughts through music.Despite its ubiquity,the origins and evolution of music remain enigmatic.Archaeological evidence has traced the history of music back at least 40000 ye... Humans across cultures convey feelings and thoughts through music.Despite its ubiquity,the origins and evolution of music remain enigmatic.Archaeological evidence has traced the history of music back at least 40000 years ago based on prehistoric bone flutes(Fitch,2006).Comparative studies have also explored earlier histories by identifying common musical features between animals and humans(Fitch,2006).For example,songbirds exhibit categorical rhythms similar to human music(Roeske et al.,2020),and humans can recognize emotional arousal in signals across all classes of terrestrial vertebrates(Filippi et al.,2017).These findings,while surprising,align with the longstanding human perception of animal signals as music(Gray et al.,2001).The universality of music and its features intensifies the fundamental question posed by Darwin(1871):how has a behavior that is energetically costly and seemingly non-adaptive evolved to become so widespread?This question can be further divided into two sub-questions(Savage et al.,2021):(1)how do musical features contribute to the production or expressive power of music(i.e.,mechanisms),and(2)how does music benefit performers in terms of survival,reproductions,or other aspects(i.e.,functions). 展开更多
关键词 COMMUNICATION origin evolution
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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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Interpretation of the Standards of Basic Dataset of Chronic Diseases Behavior Risk Factor Surveillance in Adults
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作者 ZHAO Yan Fang ZHANG Mei +3 位作者 WEI Wen Qiang SUN Ke Xin LI Xin Hua WANG Li Min 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第5期551-556,共6页
BACKGROUND China’s Behavioral Risk Factor Surveillance System(BRFSS)originated from the World Bankfunded HealthⅦLoan Project in the 1990s,which conducted behavioral risk factor surveillance in seven cities and one p... BACKGROUND China’s Behavioral Risk Factor Surveillance System(BRFSS)originated from the World Bankfunded HealthⅦLoan Project in the 1990s,which conducted behavioral risk factor surveillance in seven cities and one province^([1]).Drawing on the World Health Organization’s(WHO)STEPwise approach to surveillance(STEPs)and the U.S.Behavioral Risk Factor Surveillance System(BRFSS)^([2,3]). 展开更多
关键词 funded Basic originated
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Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities
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作者 Bing-Kun Meng Dao-Fu Song +1 位作者 Yuan Chen Sheng-Bao Shi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期777-790,共14页
A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dim... A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude oils.Based on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient sediments.Oil samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter input.It should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments. 展开更多
关键词 1 2 4 5-Tetramethylbenzene GC×GC-TofMS Organic matter origin Depositional environment
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Genetic analyses of ancient tea trees provide insights into the breeding history and dissemination of Chinese Assam tea(Camellia sinensis var.assamica)
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作者 Miao-Miao Li Muditha K.Meegahakumbura +5 位作者 Moses C.Wambulwa Kevin S.Burgess Michael Möller Zong-Fang Shen De-Zhu Li Lian-Ming Gao 《Plant Diversity》 SCIE CAS CSCD 2024年第2期229-237,共9页
Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/br... Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/breeding history remain unclear.To address this issue,we genotyped 469 ancient tea plant trees representing 26 C.sinensis var.assamica populations,plus two of its wild relatives(six and three populations of C.taliensis and C.crassicolumna,respectively)using 16 nuclear microsatellite loci.Results showed that Chinese Assam tea has a relatively high,but comparatively lower gene diversity(H_(S)=0.638)than the wild relative C.crassicolumna(H_S=0.658).Clustering in STRUCTURE indicated that Chinese Assam tea and its two wild relatives formed distinct genetic groups,with considerable interspecific introgression.The Chinese Assam tea accessions clustered into three gene pools,corresponding well with their geographic distribution.However,New Hybrids analysis indicated that 68.48%of ancient Chinese Assam tea plants from Xishuangbanna were genetic intermediates between the Puer and Lincang gene pools.In addition,10%of the ancient Chinese Assam tea individuals were found to be hybrids between Chinese Assam tea and C.taliensis.Our results suggest that Chinese Assam tea was domesticated separately in three gene pools(Puer,Lincang and Xishuangbanna)in the Mekong River valley and that the hybrids were subsequently selected during the domestication process.Although the domestication history of Chinese Assam tea in southwestern Yunnan remains complex,our results will help to identify valuable genetic resources that may be useful in future tea breeding programs. 展开更多
关键词 Tea plant Hybrid origin Genetic diversity Domestication history Camellia sinensis var.assamica Camellia taliensis
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The Inner Split in Genetics of Wu Colloquial Expression“[hÃɲ33 paʔ3 lÃɲ33 tÃɲ31]”
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作者 SONG Jia-fu 《Journal of Literature and Art Studies》 2024年第9期794-801,共8页
“[ã44 kã44 paʔ5 lã44 tã53]”(Chinese characters transcription“昂更八冷打”)is an colloquial expression in Tongxiang dialect of Suzhou-Jiaxing-Huzhou Sub-branch,Taihu Branch,Wu.It describes an awkward state with ... “[ã44 kã44 paʔ5 lã44 tã53]”(Chinese characters transcription“昂更八冷打”)is an colloquial expression in Tongxiang dialect of Suzhou-Jiaxing-Huzhou Sub-branch,Taihu Branch,Wu.It describes an awkward state with unfinished tasks.Its similar expressions can be found in other regions of Taihu Branch,including Yixing,Changzhou,Shaoxing and Ningbo,usually serving as“all”,while the expression“[hÃɲ33 paʔ3 lÃɲ33 tÃɲ31]”(“亨八冷打”)in Shanghai Sub-branch indicates“the remaining parts”when used alone.“[hÃɲ33 paʔ3 lÃɲ33 tÃɲ31]”stands for“all”only when followed by a word with meaning of“adding together”.In this paper,it is concluded and deduced from other similar morphemes that the contradictory connotations are related to an“inner split”process of an original word.Considering similar morphemes in other Chinese dialects(including Cantonese,Hakka,Jianghuai and Min),the following analysis proposes three possible original expressions and correlating trajectories of this inner phonetic-semantic split process,and selects a most credible way based on the rhyming dictionary and previous reconstructive models of ancient Chinese phonology.This presumptive analysis indicates that a broader“split and derivate”process generating new morphemes exists widely in Sinitic dialects as a natural company of phonetic features in Chinese language flow. 展开更多
关键词 WU Middle-ancient Chinese phonology Chinese dialect inner split
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Gas source of the Middle Jurassic Shaximiao Formation in the Zhongjiang large gas field of Western Sichuan Depression:Constraints from geochemical characteristics of light hydrocarbons
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作者 Xiaoqi Wu Jun Yang +4 位作者 Ping Wang Huaji Li Yingbin Chen Chunhua Ni Huasheng Zeng 《Energy Geoscience》 EI 2024年第2期141-151,共11页
The Zhongjiang gas field is a typical large gas field in terrigenous strata of the Western Sichuan Depression.It remains debatable which member of the Upper Triassic Xujiahe Formation served as the source rocks and ho... The Zhongjiang gas field is a typical large gas field in terrigenous strata of the Western Sichuan Depression.It remains debatable which member of the Upper Triassic Xujiahe Formation served as the source rocks and how significant the member contributed to the gas accumulations in the Zhongjiang gas field.In this study,we analyzed the essential characteristics of the Lower Jurassic source rocks and the geochemical features of light hydrocarbons in natural gas from the 2nd(T_(3)χ^(2))and 4th members(T_(3)χ^(4))of the Upper Triassic Xujiahe Formation(T_(3)χ),as well as the Middle Jurassic Shaximiao(J_(2)s)and Qianfoya(J_(2)q)formations.Based on this,we explored the sources of the natural gas in the Zhongjiang gas field and determined the natural gas migration patterns and their effects on the properties of light hydrocarbons in the natural gas.The results indicate that the Lower Jurassic lacustrine source rocks of the Zhongjiang gas field contain humic organic matter,with vitrinite reflectance(R_(0))values ranging from 0.86%to 0.98%.Samples meeting the criterion for effective source rocks[total organic carbon(TOC)content≥0.75%]exhibited an average TOC content of merely 1.02%,suggesting significantly lower hydrocarbon generation potential than source rocks in the underlying T3x,which show higher thermal maturity and TOC contents.For natural gas samples from T_(3)χ^(2),T_(3)χ^(4),J_(2)s,and J_(2)q reservoirs,their C_(5-7)iso-alkane content was significantly higher than their n-alkane content,and their methylcyclohexane(MCH)index ranged from 59.0%to 77.3%,indicating the predominance of methylcyclohexane in C_(7)light hydrocarbons.As indicated by the origin identification and gas-source correlation based on the geochemical features of light hydrocarbons,the natural gas in the Zhongjiang gas field is typical coal-derived gas.The gas from the primary pay zone of the Shaximiao Formation,with significantly high K_(1),(P_(2)+N_(2))/C_(7),and P_(3)/C_(7)values,predominantly originated from the 5th member of the T3x and migrated in the free phase,with a small amount possibly sourced from the Lower Jurassic source rocks.The dissolution and adsorption during gas migration led to a decrease in the aromatic content in C_(6-7)light hydrocarbons and an increase in the isoheptane values.Therefore,their effects must be considered when determining the gas origin and thermal maturity based on the aromatic content in C_(6-7) light hydrocarbons and iso-heptane values. 展开更多
关键词 Zhongjiang gas field Source rock origin of natural gas Light hydrocarbon geochemistry Natural gas migration
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Tracing of natural gas migration by light hydrocarbons:A case study of the Dongsheng gas field in the Ordos Basin,NW China
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作者 WU Xiaoqi NI Chunhua +3 位作者 MA Liangbang WANG Fubin JIA Huichong WANG Ping 《Petroleum Exploration and Development》 SCIE 2024年第2期307-319,共13页
Based on the analysis of light hydrocarbon compositions of natural gas and regional comparison in combination with the chemical components and carbon isotopic compositions of methane,the indication of geochemical char... Based on the analysis of light hydrocarbon compositions of natural gas and regional comparison in combination with the chemical components and carbon isotopic compositions of methane,the indication of geochemical characteristics of light hydrocarbons on the migration features,dissolution and escape of natural gas from the Dongsheng gas field in the Ordos Basin is revealed,and the effect of migration on specific light hydrocarbon indexes is further discussed.The study indicates that,natural gas from the Lower Shihezi Formation(Pix)in the Dongsheng gas field displays higher iso-C5-7contents than n-C5-7contents,and the C6-7light hydrocarbons are composed of paraffins with extremely low aromatic contents(<0.4%),whereas the C7light hydrocarbons are dominated by methylcyclohexane,suggesting the characteristics of coal-derived gas with the influence by secondary alterations such as dissolution.The natural gas from the Dongsheng gas field has experienced free-phase migration from south to north and different degrees of dissolution after charging,and the gas in the Shiguhao area to the north of the Borjianghaizi fault has experienced apparent diffusion loss after accumulation.Long-distance migration in free phase results in the decrease of the relative contents of the methylcyclohexane in C7 light hydrocarbons and the toluene/n-heptane ratio,as well as the increase of the n-heptane/methylcyclohexane ratio and heptane values.The dissolution causes the increase of isoheptane values of the light hydrocarbons,whereas the diffusion loss of natural gas in the Shiguhao area results in the increase of n-C5-7contents compared to the iso-C5-7contents. 展开更多
关键词 Ordos Basin Dongsheng gas field Permian Lower Shihezi Formation light hydrocarbon compounds MATURITY natural gas origin migration phase state diffusion loss
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Extraterrestrial Life in the Thermosphere: Plasmas, UAP, Pre-Life, Fourth State of Matter
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作者 R. Joseph C. Impey +8 位作者 O. Planchon R. del Gaudio M. Abu Safa A. R. Sumanarathna E. Ansbro D. Duvall G. Bianciardi C. H. Gibson R. Schild 《Journal of Modern Physics》 2024年第3期322-376,共55页
“Plasmas” up to a kilometer in size and behaving similarly to multicellular organisms have been filmed on 10 separate NASA space shuttle missions, over 200 miles above Earth within the thermosphere. These self-illum... “Plasmas” up to a kilometer in size and behaving similarly to multicellular organisms have been filmed on 10 separate NASA space shuttle missions, over 200 miles above Earth within the thermosphere. These self-illuminated “plasmas” are attracted to and may “feed on” electromagnetic radiation. They have different morphologies: 1) cone, 2) cloud, 3) donut, 4) spherical-cylindrical;and have been filmed flying towards and descending from the thermosphere into thunderstorms;congregating by the hundreds and interacting with satellites generating electromagnetic activity;approaching the Space Shuttles. Computerized analysis of flight path trajectories documents these plasmas travel at different velocities from different directions and change their angle of trajectory making 45°, 90°, and 180° shifts and follow each other. They’ve been filmed accelerating, slowing down, stopping, congregating, engaging in “hunter-predatory” behavior and intersecting plasmas leaving a plasma dust trail in their wake. Similar life-like behaviors have been demonstrated by plasmas created experimentally. “Plasmas” may have been photographed in the 1940s by WWII pilots (identified as “Foo fighters”);repeatedly observed and filmed by astronauts and military pilots and classified as Unidentified Aerial—Anomalous Phenomenon. Plasmas are not biological but may represent a form of pre-life that via the incorporation of elements common in space, could result in the synthesis of RNA. Plasmas constitute a fourth state of matter, are attracted to electromagnetic activity, and when observed in the lower atmosphere likely account for many of the UFO-UAP sightings over the centuries. 展开更多
关键词 Extraterrestrials PLASMAS Dusty Plasmas EXTREMOPHILES Life in Space Abiogenesis origins of Life RNA World
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The Rise and Fall of the Minnan Dialect
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作者 郭诗涵 郭金涛(指导) 《疯狂英语(初中天地)》 2024年第9期68-69,共2页
The Minnan dialect,is characterized by its gentle tone and fluid rhythm.This dialect,with its rich history,has undergone significant evolution over the centuries.The earliest origins of the Minnan dialect can be trace... The Minnan dialect,is characterized by its gentle tone and fluid rhythm.This dialect,with its rich history,has undergone significant evolution over the centuries.The earliest origins of the Minnan dialect can be traced back to the Shang Dynasty,with its development linked to the Yellow River and the Luo River basin during the Western Jin Dynasty. 展开更多
关键词 HAS GENTLE origin
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The telomere-to-telomere genome of Fragaria vesca reveals the genomic evolution of Fragaria and the origin of cultivated octoploid strawberry 被引量:13
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作者 Yuhan Zhou Jinsong Xiong +10 位作者 Ziqiang Shu Chao Dong Tingting Gu Pengchuan Sun Shuang He Mian Jiang Zhiqiang Xia Jiayu Xue Wasi Ullah Khan Fei Chen Zong-Ming Cheng 《Horticulture Research》 SCIE CSCD 2023年第4期101-109,共9页
Fragaria vesca,commonly known as wild or woodland strawberry,is the most widely distributed diploid Fragaria species and is native to Europe and Asia.Because of its small plant size,low heterozygosity,and relative eas... Fragaria vesca,commonly known as wild or woodland strawberry,is the most widely distributed diploid Fragaria species and is native to Europe and Asia.Because of its small plant size,low heterozygosity,and relative ease of genetic transformation,F.vesca has been a model plant for fruit research since the publication of its Illumina-based genome in 2011.However,its genomic contribution to octoploid cultivated strawberry remains a long-standing question.Here,we de novo assembled and annotated a telomere-to-telomere,gap-free genome of F.vesca‘Hawaii 4’,with all seven chromosomes assembled into single contigs,providing the highest completeness and assembly quality to date.The gap-free genome is 220785082 bp in length and encodes 36173 protein-coding gene models,including 1153 newly annotated genes.All 14 telomeres and seven centromeres were annotated within the seven chromosomes.Among the three previously recognized wild diploid strawberry ancestors,F.vesca,F.iinumae,and F.viridis,phylogenomic analysis showed that F.vesca and F.viridis are the ancestors of the cultivated octoploid strawberry F.×ananassa,and F.vesca is its closest relative.Three subgenomes of F.×ananassa belong to the F.vesca group,and one is sister to F.viridis.We anticipate that this high-quality,telomere-to-telomere,gap-free F.vesca genome,combined with our phylogenomic inference of the origin of cultivated strawberry,will provide insight into the genomic evolution of Fragaria and facilitate strawberry genetics and molecular breeding. 展开更多
关键词 straw FRAGARIA origin
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The Translation of Chinese Literature under the Theory of Translation Compensation
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作者 WANG Rong 《Philosophy Study》 2024年第1期9-15,共7页
In order to promote the exchange of Chinese culture with foreign countries,translators bear an important mission in the process of cross-cultural communication.Although there are cultural differences,we can achieve cu... In order to promote the exchange of Chinese culture with foreign countries,translators bear an important mission in the process of cross-cultural communication.Although there are cultural differences,we can achieve cultural dissemination and exchange through continuous cultural dialogue.As an important way for foreign scholars to understand the history of the Shang and Zhou Dynasties in China,the translation of historical texts is crucial.Multiple typical cases are selected under the guidance of the translation theory of compensation to use relevant methods or techniques from the three levels of language,culture,and aesthetics to compensate for the loss of Li Xueqin’s The Origin of Ancient Chinese Civilization in English translation proofreading. 展开更多
关键词 translation compensation theory Li Xueqin the origin of Ancient Chinese Civilization
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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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Correction:Geochronology and origin of Paleoproterozoic charnockites with old crustal signature in the Haisyn block of the Ukrainian shield
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《Acta Geochimica》 EI CAS CSCD 2023年第3期583-583,共1页
In the original publication of the article,Pbr should be replaced with Pb in Table 2.The correct Table 2 is provided in this article.
关键词 CRUSTAL origin Paleo
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Analysis of the COVID-19, Outbreak in Brazil Using Topological Weighted Centroid: An Intelligent Geographic Information System Approach
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作者 Masoud Asadi-Zeydabadi Marina Mizukoshi +2 位作者 Massimo Buscema Giulia Massini Weldon Lodwick 《Journal of Data Analysis and Information Processing》 2024年第2期248-266,共19页
This study used Topological Weighted Centroid (TWC) to analyze the Coronavirus outbreak in Brazil. This analysis only uses latitude and longitude in formation of the capitals with the confirmed cases on May 24, 2020 t... This study used Topological Weighted Centroid (TWC) to analyze the Coronavirus outbreak in Brazil. This analysis only uses latitude and longitude in formation of the capitals with the confirmed cases on May 24, 2020 to illustrate the usefulness of TWC though any date could have been used. There are three types of TWC analyses, each type having five associated algorithms that produce fifteen maps, TWC-Original, TWC-Frequency and TWC-Windowing. We focus on TWC-Original to illustrate our approach. The TWC method without using the transportation information predicts the network for COVID-19 outbreak that matches very well with the main radial transportation routes network in Brazil. 展开更多
关键词 COVID-19 Topological Weighted Centroid (TWC) Algorithms TWC-original TWC-Frequency and TWC-Windowing
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Discussion on the Origin of Chinese Modernization from the Perspective of Classical Marxist Theory 被引量:1
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作者 Zhiqin Su Haipeng Jiang 《Journal of Contemporary Educational Research》 2023年第11期119-126,共8页
Chinese modernization is socialist modernization with Chinese characteristics under the leadership of the Communist Party of China,and it is the contemporary form of Chinese socialist modernization under the grand his... Chinese modernization is socialist modernization with Chinese characteristics under the leadership of the Communist Party of China,and it is the contemporary form of Chinese socialist modernization under the grand historical vision,which has considerable research value.This paper mainly combines the theoretical vision with the historical vision,studies and discusses the origin of Chinese modernization,from China’s“Oriental society,”a modern prehistoric social form,to modern China stepping on the socialist road under the basic circumstances of world history,and takes the initiative to master the relevant logic of the historical trend.This paper also presents the research and discussion on why it is possible for modern China to realize Chinese modernization,and to solve the problem of the origin of Chinese modernization in theory and historical logic. 展开更多
关键词 Marxist theory Chinese-style modernization the problem of origin
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Textual Research on Name, Variety and Property of the Multi-origin Tibetan Herb "Azhong"
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作者 Zhuomacuomao Suolanglazong Cairangnanjia 《Agricultural Biotechnology》 CAS 2023年第4期52-57,共6页
By consulting ancient Tibetan medical literature such as books of materia medica,medical works,and prescription books,as well as modern and contemporary literature and materials,and in combination with the interview a... By consulting ancient Tibetan medical literature such as books of materia medica,medical works,and prescription books,as well as modern and contemporary literature and materials,and in combination with the interview and investigation of clinical use and expert consultation,we collated and verified the name,variety classification,plant origin,application and other recorded information of Tibetan herb"Azhong",and summarized and analyzed the phenomenon of mixed use or substitution of medicinal plants.According to textual research,it first appeared in the Four Medical Tantras.The Tibetan herb"Azhong"is simply recorded in the ancient books and Materia Medica,which are collectively called"Azhong".Since the 15 th century,there have been varieties such as Za Azhong,Kan Azhong,Xing Azhong,Pumou Azhong,Zha Azhong,Bang Azhong,and the top grade is called Azhong Nabu and Nacang Azhong,and the bottom grade is Azhong Gabu.According to modern literature,the origin of"Azhong"involves 12 species of plants belonging to 8 genera,5 families.At present,Arenaria kansuensis Maxim,Ajania purpurea Shih.and Thalictrum squamiferum Lecoy are the mainstream medicinal materials of"Azhong".There is a certain basis for clinical application and theoretical records in the literature in terms of the mutual alternative use of Tibetan medicinal materials such as"Azhong"and traditional medicinal materials in different regions.Therefore,it is necessary to use modern chemical technology and pharmacological experiments to conduct a comparative study on the material basis and biological activity of different varieties of medicinal materials,and carry out a survey on resources and use status,so as to standardize the use of their varieties and origins and improve the safety of clinical medication. 展开更多
关键词 Tibetan medicine Azhong origin Drug property
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The Origin and Preservation of Suspended Barites near the 90°E Ridge in the Northeastern Indian Ocean
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作者 BU Xuejiao LIU Ming +5 位作者 DING Yi YANG Yadi HUANG Mu SUN Xiaoxia FAN Dejiang YANG Zuosheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期88-98,共11页
Suspended particulate barite crystals were detected in the water columns at four different stations near the 90°E ridge in the Indian Ocean.Four distinct morphological types of marine barites were distinguished:e... Suspended particulate barite crystals were detected in the water columns at four different stations near the 90°E ridge in the Indian Ocean.Four distinct morphological types of marine barites were distinguished:euhedral-subhedral crystals,oval or round crystals,rhombic crystals,and irregular crystals.The barite crystals in the study area are typically fine,with a dominant size of 1–3μm.The vertical distribution of barites is significantly affected by the formation and sedimentation processes.Barites begin to appear at a depth of 30 m and are formed primarily from the surface to the depth of 2000m with a concentration peak at the depth of 200m,where particles are coarser than those in the other layers.The barites begin to settle and dissolve once formed in the water column,resulting in finer barite particles and lower particle concentrations.The formation of barite crystals is related to biological processes associated with the decomposition of barium-rich skeletons in the microenvironment of decaying organic matter that is affected by the primary productivity and dissolved oxygen content in the water column.The dissolving process of barite crystals showed similar variation with the concentration of dissolved barium in ocean water,and the substitution of strontium for barite in crystals promotes the selective dissolution of barite and exerts an important impact on its morphology.It is approximately 33%of barites in the amount and 22%in the concentration to settle to the bottom of the water column compared to that observed in the main barite formation zone. 展开更多
关键词 marine barite Indian Ocean origin and sedimentation process dissolution and preservation
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