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Paleoenvironmental Characteristics of Paleogene Lacustrine Source Rocks in the Western Bozhong Sag,Bohai Bay Basin,China:Evidence from Biomarkers,Major and Trace Elements
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作者 WANG Xiang LIU Guangdi +6 位作者 SONG Zezhang SUN Mingliang WANG Xiaolin WANG Feilong CHEN Rongtao GENG Mingyang LI Yishu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期220-240,共21页
The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these i... The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were studied.The above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater conditions.Comparatively,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and salinity.During the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant algae.Moreover,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial input.The OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and bacteria.Tectonic subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct differences.Overall,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace elements.The established models may have positive implications for research of lacustrine source rocks in offshore areas with few drillings. 展开更多
关键词 petroleum geology source rocks depositional environments biomarkers major elements trace elements Bozhong Sag
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Enriched Constant Elements in the Boundary Element Method for Solving 2D Acoustic Problems at Higher Frequencies
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作者 Zonglin Li Zhenyu Gao Yijun Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2159-2175,共17页
The boundary element method(BEM)is a popular method for solving acoustic wave propagation problems,especially those in exterior domains,owing to its ease in handling radiation conditions at infinity.However,BEM models... The boundary element method(BEM)is a popular method for solving acoustic wave propagation problems,especially those in exterior domains,owing to its ease in handling radiation conditions at infinity.However,BEM models must meet the requirement of 6–10 elements per wavelength,using the conventional constant,linear,or quadratic elements.Therefore,a large storage size of memory and long solution time are often needed in solving higher-frequency problems.In this work,we propose two new types of enriched elements based on conventional constant boundary elements to improve the computational efficiency of the 2D acoustic BEM.The first one uses a plane wave expansion,which can be used to model scattering problems.The second one uses a special plane wave expansion,which can be used tomodel radiation problems.Five examples are investigated to showthe advantages of the enriched elements.Compared with the conventional constant elements,the new enriched elements can deliver results with the same accuracy and in less computational time.This improvement in the computational efficiency is more evident at higher frequencies(with the nondimensional wave numbers exceeding 100).The paper concludes with the potential of our proposed enriched elements and plans for their further improvement. 展开更多
关键词 Enriched boundary elements constant elements 2D acoustic problems higher frequency
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Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture
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作者 Maria Kaleem Erum Bashir +2 位作者 Shahid Naseem Tahir Rafique Bushra Shahab 《Acta Geochimica》 EI CAS CSCD 2024年第2期214-234,共21页
This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by mu... This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical data.The outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the region.Twenty-five soil samples were collected,mainly from the arable land of the Porali Plain.After drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric analysis.Esti-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial distribution.The granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt type.Weathering indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of alteration.These indices reflect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr ratios.Assessment of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the soils.The correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type mineralization.Weathering may result in the undesirable accumulation of certain trace elements which adversely affects crops. 展开更多
关键词 Weathering indices Pollution indices ACCUMULATION Repercussions Trace elements Multivariate analyses Porali Plain BALOCHISTAN
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Trace elements in magmatic and hydrothermal quartz:Implications on the genesis of the Xingluokeng Tungsten Deposit,South China
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作者 Qing-Qing Zhang You-Wei Chen Jian-Feng Gao 《Acta Geochimica》 EI CAS CSCD 2024年第3期441-458,共18页
The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South China.The Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,and... The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South China.The Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained granite.The deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and sericitization.This study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and veins.Trace element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace Si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge compensators.Low Ge/Al ratios(<0.013)of quartz from granites suggest a mag-matic origin.The low Al/Ti and Ge/Ti ratios,accompanied by high Ti contents in quartz,suggest that the porphyritic biotite granite and biotite granite are characterized by rela-tively low levels of differentiation and high crystallization temperatures.In contrast,thefine-grained granite exhibits a higher degree of fractionation,lower crystallization tem-peratures,and a closer association with tungsten miner-alization.Ti contents in quartz from quartz veins indicate Qz-Ⅰformed at temperatures above 400°C,while Qz-Ⅱto Qz-Ⅴformed at temperatures below 350°C.Variations in different generations of quartz,as indicated by Al content and(Al+Fe)/(Li+Na+K)ratio,suggest that Qz-Ⅰprecipi-tated from a less acidicfluid with a stable pH,whereas Qz-Ⅱto Qz-Ⅴoriginated from a more acidicfluid with notable pH variations.Consequently,alkaline alteration and acidic alteration supplied the essential Ca and Fe for the precipita-tion of scheelite and wolframite,respectively,highlighting a critical mechanism in tungsten mineralization at the Xin-gluokeng deposit. 展开更多
关键词 QUARTZ Xingluokeng Tungsten deposit Trace elements South China
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Genesis of the Nuri Cu-W-Mo Deposit,Tibet,China:Constraints from in situ Trace Elements and Sr Isotopic Analysis of Scheelite
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作者 WANG Yiyun WU Zhishan +8 位作者 CHEN Wenqing DU Qing’an TANG Liwei SHI Hongzhao MA Guotao ZHANG Zhi LIANG Wei WU Bo MIAO Hengyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期117-131,共15页
The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controver... The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controversial since its discovery.Based on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,respectively.Through LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are investigated.Scanning Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth band.In contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and homogeneous.The normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock interaction.Combining the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric water.The intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a gradual decrease in oxygen fugacity(fO2)and a slow rise in pH value.Additionally,the high Mo and low Sr contents in the scheelite are consistent with typical characteristics of magmatic-hydrothermal scheelite.Therefore,considering the geological features of the deposit,the geochemical characteristics of scheelite and the O-H isotope data published previously,it can be concluded that the genesis of the Nuri deposit belongs to porphyry-skarn deposit. 展开更多
关键词 trace elements in situ Sr isotopes tungsten mineralization Gangdese metallogenic belt TIBET
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Pig H3K4me3,H3K27ac,and gene expression profiles reveal reproductive tissue-specific activity of transposable elements
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作者 Tao Jiang Zhi-Min Zhou +6 位作者 Zi-Qi Ling Qing Zhang Zhong-Zi Wu Jia-Wen Yang Si-Yu Yang Bin Yang Lu-Sheng Huang 《Zoological Research》 SCIE CSCD 2024年第1期138-151,共14页
Regulatory sequences and transposable elements(TEs)account for a large proportion of the genomic sequences of species;however,their roles in gene transcription,especially tissue-specific expression,remain largely unkn... Regulatory sequences and transposable elements(TEs)account for a large proportion of the genomic sequences of species;however,their roles in gene transcription,especially tissue-specific expression,remain largely unknown.Pigs serve as an excellent animal model for studying genomic sequence biology due to the extensive diversity among their wild and domesticated populations.Here,we conducted an integrated analysis using H3K27ac ChIP-seq,H3K4me3 ChIP-seq,and RNA-seq data from 10 different tissues of seven fetuses and eight closely related adult pigs.We aimed to annotate the regulatory elements and TEs to elucidate their associations with histone modifications and mRNA expression across different tissues and developmental stages.Based on correlation analysis between mRNA expression and H3K27ac and H3K4me3 peak activity,results indicated that H3K27ac exhibited stronger associations with gene expression than H3K4me3.Furthermore,1.45%of TEs overlapped with either the H3K27ac or H3K4me3 peaks,with the majority displaying tissue-specific activity.Notably,a TE subfamily(LTR4C_SS),containing binding motifs for SIX1 and SIX4,showed specific enrichment in the H3K27ac peaks of the adult and fetal ovaries.RNA-seq analysis also revealed widespread expression of TEs in the exons or promoters of genes,including 4688 TE-containing transcripts with distinct development stage-specific and tissue-specific expression.Of note,1967 TE-containing transcripts were enriched in the testes.We identified a long terminal repeat(LTR),MLT1F1,acting as a testis-specific alternative promoter in SRPK2(a cell cycle-related protein kinase)in our pig dataset.This element was also conserved in humans and mice,suggesting either an ancient integration of TEs in genes specifically expressed in the testes or parallel evolutionary patterns.Collectively,our findings demonstrate that TEs are deeply embedded in the genome and exhibit important tissue-specific biological functions,particularly in the reproductive organs. 展开更多
关键词 Transposable elements PORCINE Histone modification Alternative promoter TE-containing transcript
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Evaluation of Trace Elements in the Soil of Typical Peach Orchards in Zunyi City
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作者 Wenzhao LI Xiong YAN +5 位作者 Jun CHENG Xingyong WANG Changling SUI Xiangchun ZHANG Zhuang ZHAO Peng ZHOU 《Agricultural Biotechnology》 2024年第1期17-19,共3页
[Objectives]This study was conducted to clarify the enrichment and paucity of trace elements in the soil environment of peach orchards in Zunyi City,and to provide reference for supplementary application of microeleme... [Objectives]This study was conducted to clarify the enrichment and paucity of trace elements in the soil environment of peach orchards in Zunyi City,and to provide reference for supplementary application of microelement fertilizers and high-quality peach production in peach orchards.[Methods]Taking the soil of three typical peach orchards(Taoli Renjia peach orchard,Pengrui peach orchard and Taohuadao peach orchard)in Shenxi Town,Honghuagang District,Zunyi City as the research object,the contents of trace elements in soil were analyzed through field sampling and indoor determination of trace elements.[Results]The effective contents of trace elements in the soil of peach orchard bases in the study area were at a medium level,and the soil of the peach orchards was rich in available Fe and Se.The contents of available Cu,Mo and Mn were relatively rich.The contents of available B were not high overall.The contents of available Zn were at a moderate to low level overall.The soil of Taoli Renjia peach orchard was relatively rich in trace elements.[Conclusions]The research results can provide a scientific basis for the production of high-quality crispy peaches in peach orchards. 展开更多
关键词 Zunyi Soil in peach orchard Trace elements EVALUATION
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Mobility of Major and Trace Elements during the Bauxitization Processes in Ngaoundal Area (Adamawa Cameroon): Implication on Mining Perspectives
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作者 André Sini Harouna Boukari +4 位作者 Ondoa Augustin Désiré Balla Djetenbe Beral Salomon Wangmené Awé Simon Djakba Basga Jean Pierre Nguetnkam 《Open Journal of Geology》 CAS 2024年第1期81-100,共20页
This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical ... This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical analyses were carried out. Four facies of duricrust were identified and characterized from the summit to the top of the slope of the Ngaoundal mountain: scoriaceous, pisolitic, nodular and massive. Mineralogical and geochemical analyses performed on 16 samples, revealed a significant concentration of Al<sub>2</sub>O<sub>3</sub> mainly in the scoriaceous facies (over 45% in grade), moderate in Fe<sub>2</sub>O<sub>3</sub> (averaging 23.69%) and SiO<sub>2</sub> (averaging 21.7%). Trace elements were generally low, excluding Cr (421 ppm on average), Zr (327 ppm on average and V (213 ppm on average). In addition, the limited quantities of alkalis (Na<sub>2</sub>O, K<sub>2</sub>O) and alkaline earths metals (MgO, CaO) coupled with the very high values of Chemical Index of Alteration (CIA) and Mineralogical Index of Alteration (MIA), (more than 99%) attest to the intense weathering of the studied materials. Allitization and monosiallitization constituted the crystallochemical phenomena that have led to the development of bauxitic minerals. More than 90% of gibbsite in scoriaceous facies, 52.21% - 76.01% of kaolinite in pisolitic facies and more than 40% of hematite in nodular facies were quantified. The relationships between the constitutive components indicated their interdependency during the bauxitization phenomenon. The mineralogical and geochemical properties highlighted the mining interest of the studied duricrusts to be valorized. 展开更多
关键词 Duricrust Bauxitization Phenomenon Mineralogical and Geochemical Characterization Major and Trace elements Mining Potential
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Preliminary Study of Chemical Elements Distribution in Petroleum Source Rocks Donga and Yogou Formations of the Termit Sedimentary Basin (Est-Niger)
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作者 Alassane Ibrahim Maman Bachir Abdoulaye Dan Makaou Oumarou +2 位作者 Baraou Idi Souley Kouakou Alponse Yaou Abdoulwahid Sani 《Journal of Minerals and Materials Characterization and Engineering》 2024年第1期49-62,共14页
XRF and EDX analyses were carried out on 18 batches of representative raw samples to determine the distribution of major chemical elements in the petroleum source rocks of Donga and Yogou formations of Termit sediment... XRF and EDX analyses were carried out on 18 batches of representative raw samples to determine the distribution of major chemical elements in the petroleum source rocks of Donga and Yogou formations of Termit sedimentary basin. The chemical composition of these formations is dominated by silicon (Si), aluminum (Al) and iron (Fe). This is consistent with the oxide composition, which is also dominated by silicon oxide (SiO2), aluminum oxide (Al<sub>2</sub>O<sub>3</sub>) and iron monoxide (FeO). No less important chemical elements are calcium (Ca), potassium (K), sulfur (S), titanium (Ti), magnesium (Mg), manganese (Mn) and barium (Ba), as well as some of their oxides. All these major chemical elements are carried by silicate detrital minerals associated with pyrite and goethite and/or clay minerals such as kaolinite and interstratified illite, smectite and chlorite. This trend is illustrated by the values of the Si/Al and SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ratios. 展开更多
关键词 DISTRIBUTION Major elements Source Rocks Donga Formation Yogou Formation Termit Basin
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Teaching Research and Effect Observation on the Integration of Clinical Medicine Integrated Course and Ideological and Political Elements from the Perspective of“Sanquan Education”
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作者 Wensi Liu Chunyan Zhao +4 位作者 Xiangying Kong Zhiwu Ji Cuicui Yu Fuxiang Song Jincai Shang 《Journal of Contemporary Educational Research》 2024年第4期270-275,共6页
Purpose:To analyze the application path of the integration of clinical medicine integrated courses with the elements of ideology and politics under the theory of“Sanquan Education,”and to provide references for the ... Purpose:To analyze the application path of the integration of clinical medicine integrated courses with the elements of ideology and politics under the theory of“Sanquan Education,”and to provide references for the promotion of educational reform in medical schools.Methods:60 clinical medicine undergraduates at Jiamusi University in 2018 and 2019 were randomly selected as research subjects.On the basis of the analysis of students’characteristics and pre-study content,the students were divided into the integration group and the traditional group,each with 30 students.Students in the integration group carried out clinical medicine integrated class with the integration of ideological and political elements.Students in the traditional group carried out the traditional clinical medicine integrated class.Classroom evaluation scales,anonymous questionnaires,and interviews were used to conduct research,collect data,and compare and observe the application effects.Results:After carrying out different modes of clinical medicine integrated courses,the undergraduates of the Excellent Physician Class in the integration group were higher than those in the traditional group in terms of teaching satisfaction,comprehensive quality,basic knowledge test,and case analysis scores through questionnaire analysis(P<0.05).In the evaluation of the effect of ideological education,the undergraduates of the Excellent Physician Class of the integration group were higher than the traditional group in terms of the acceptance of doctor-patient communication,the correct rate of mastering the history of the discipline,and the correct rate of mastering the frontiers and policies(P<0.05).Conclusion:Through the integration of clinical medicine integrated course and ideological and political elements,we can help students establish correct values while teaching them professional knowledge,improve the implementation of moral education in medical schools,cultivate excellent medical workers with high morality and firm beliefs for the society,and realize the fundamental educational task of establishing morality and educating people in medical schools in the context of“Sanquan Education.” 展开更多
关键词 Sanquan Education Clinical medicine integrated course Ideological and political elements TEACHING
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Research on Narrative Design of Creative Products Based on Regional Cultural Elements
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作者 Qiqiong Huang Mohd Mustafa Mohd Ghazali 《Journal of Contemporary Educational Research》 2024年第1期65-73,共9页
The research explored the ways and means of narrative design in which regional cultural elements are integrated into cultural and creative products.It also researched a new way of thinking and methods of creative prod... The research explored the ways and means of narrative design in which regional cultural elements are integrated into cultural and creative products.It also researched a new way of thinking and methods of creative product design based on regional cultural elements in order to satisfy consumers’emotional and cultural experiences.Narrative theory takes the perspective of narrative expression in the design of cultural and creative products.The regional cultural elements were used for better interactive communication with consumers in the form of cultural and creative products.In the narrative of cultural and creative product design,intervening in the development of regional cultural and creative design from the perspective of narratology can better exert and create the cultural value of the region itself,with cultural and creative products playing an important role in“local cultural stories.”This research adopted a qualitative approach and provided ideas and guidance for the narrative design and expression of regional cultural elements in creative products through comparative analysis of case studies.The research highlighted the role of narrative design in creating multi-layered experiences,weaving regional cultural stories into products,and the importance of deep understanding and effective use of regional cultural elements in design. 展开更多
关键词 Regional cultural elements Creative products Narrative design
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Distribution, health and ecological risk assessments of trace elements in Nigerian oil sands
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作者 Odunayo T.Ore Festus M.Adebiyi 《Acta Geochimica》 EI CAS CSCD 2024年第1期59-71,共13页
The Nigerian oil sands represent the largest oil sand deposit in Africa, yet there is little published information on the distribution and potential health and ecological risks of trace elements in the oil resource. I... The Nigerian oil sands represent the largest oil sand deposit in Africa, yet there is little published information on the distribution and potential health and ecological risks of trace elements in the oil resource. In the present study, we investigated the distribution pattern of 18trace elements(including biophile and chalcophile elements) as well as the estimated risks associated with exposure to these elements. The results of the study indicated that Fe was the most abundant element, with a mean concentration of 22,131 mg/kg while Br had the lowest mean concentration of 48 mg/kg. The high occurrence of Fe and Ti suggested a possible occurrence of ilmenite(Fe TiO_(3)) in the oil sands. Source apportionment using positive matrix factorization showed that the possible sources of detected elements in the oil sands were geogenic, metal production, and crustal. The contamination factor, geo-accumulation index, modified degree of contamination, pollution load index, and Nemerow pollution index indicated that the oil sands are heavily polluted by the elements. Health risk assessment showed that children were relatively more susceptible to the potentially toxic elements in the oil sands principally via ingestion exposure route(HQ > 1E-04). Cancer risks from inhalation are unlikely due to CR < 1E-06 but ingestion and dermal contact pose severe risks(CR > 1E-04). The high concentrations of the elements pose serious threats due to the potential for atmospheric transport, bioaccessibility, and bioavailability. 展开更多
关键词 Biophile Chalcophile Oil sand Risk assessment Trace element
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Mobile genetic elements facilitate the transmission of antibiotic resistance genes in multidrug-resistant Enterobacteriaceae from duck farms
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作者 Xin’er Zheng Dingting Xu +5 位作者 Jinchang Yan Min Qian Peng Wang Davood Zaeim Jianzhong Han Daofeng Qu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期729-735,共7页
Multidrug-resistant(MDR)Enterobacteriaceae critically threaten duck farming and public health.The phenotypes,genotypes,and associated mobile genetic elements(MGEs)of MDR Enterobacteriaceae isolated from 6 duck farms i... Multidrug-resistant(MDR)Enterobacteriaceae critically threaten duck farming and public health.The phenotypes,genotypes,and associated mobile genetic elements(MGEs)of MDR Enterobacteriaceae isolated from 6 duck farms in Zhejiang Province,China,were investigated.A total of 215 isolates were identified as Escherichia coli(64.65%),Klebsiella pneumoniae(12.09%),Proteus mirabilis(10.23%),Salmonella(8.84%),and Enterobacter cloacae(4.19%).Meanwhile,all isolates were resistant to at least two antibiotics.Most isolates carried tet(A)(85.12%),blaTEM(78.60%)and sul1(67.44%)resistance genes.Gene co-occurrence analysis showed that the resistance genes were associated with IS26 and integrons.A conjugative IncFII plasmid pSDM004 containing all the above MGEs was detected in Proteus mirabilis isolate SDM004.This isolate was resistant to 18 antibiotics and carried the blaNDM-5 gene.MGEs,especially plasmids,are the primary antibiotic resistance gene transmission route in duck farms.These findings provide a theoretical basis for the rational use of antibiotics in farms which are substantial for evaluating public health and food safety. 展开更多
关键词 Duck farm Mobile genetic element Antibiotic resistance gene PLASMID Food safety
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Research on Dong Zhongshu’s Five Elements Thought
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作者 WEI Keyin 《Cultural and Religious Studies》 2023年第11期541-548,共8页
Dong Zhongshu reordered the Five Elements,that is,wood,fire,soil,gold,and water,and believed that this was the order given by heaven and could not be changed.The Five Elements are related to each other.The relationshi... Dong Zhongshu reordered the Five Elements,that is,wood,fire,soil,gold,and water,and believed that this was the order given by heaven and could not be changed.The Five Elements are related to each other.The relationship between the two adjacent to each other is the relationship of generation and father-son;the relationship between the two separated is reciprocal.The soil is in the middle,and the soil has the noblest morality.Therefore,Dong Zhongshu’s view of“Filial piety is natural”originates from the father-son relationship between the Five Elements and the nobility of soil virtue.According to the Five Elements,the state management should set up five kinds of official posts in order to achieve the purpose of interdependence,mutual restriction,balance,and promotion.Dong Zhongshu matched the Five Elements with the four seasons,and believed that each of the Five Elements had its own virtues,and thus extended it to the virtues of the monarch.Dong Zhongshu linked the Five Elements with the five things,thinking that the five things of the king will affect the Five Elements;the five things are appearance,speech,sight,listening,thinking,which is given by heaven.To govern the country and the people the king must have five important cultivations. 展开更多
关键词 Dong Zhongshu Five elements the Five elements intergrowth the Five elements overcoming five things Book Chunqiu Fanlu
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The Psychosomatic Traits of“People with the Five Elements in Traditional Chinese Medicine”:A Qualitative Study 被引量:2
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作者 LI Jia Jia YANG Xin Yu +6 位作者 ZHANG Hong Jun YIN Dong Qing ZHANG Jin Tao CUI Jing Wen HAN Jing Dong MA Yan JIA Hong Xiao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第11期1068-1078,共11页
Objective To identify the representative attributes of the five elements of a person with a qualitative methodology and provide the basis for the clinical diagnosis and treatment of“people with the five elements in t... Objective To identify the representative attributes of the five elements of a person with a qualitative methodology and provide the basis for the clinical diagnosis and treatment of“people with the five elements in traditional Chinese medicine(TCM).”Methods Data collected from the literature review,two sessions of brainstorming of experts with related experience in“people with the five elements in TCM”from October 2020 to December 2020,and six rounds of in-depth interviews with 30 participants who had various attributes of the five elements from March 2021 to October 2021 were analyzed.Triangulation was used in this study,and theming and synthesizing were used to analyze the data.Results A total of 31 experts and 30 interviewees participated in this study.The median age of the experts and interviewees were 48.0 and 38.5 years,respectively;51.66%and 54.8%of experts and interviewees,respectively,were men.The descriptors of facial diagrams of“people with the five elements in TCM”were complexion,shape,distribution state of facial bones,convergence trend of facial muscles,and facial expression.A theoretical model of“people with the five elements in TCM”was shaped based on these findings.Conclusion The study suggests a possibility for bridging the gap between personality and bodily state,identifying an avenue for personality research from the perspective of TCM. 展开更多
关键词 People with the five elements in TCM BRAINSTORMING In-depth interviews TRIANGULATION PERSONALITY Traditional Chinesemedicine
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Effects of Rare-earth and Microalloying Elements on the Microstructure Characteristics of Hypereutectoid Rails
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作者 戴宇恒 ZHAO Wenqian +1 位作者 包喜荣 陈林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期682-688,共7页
We performed thermal simulation experiments of double-pass deformation of hypereutectoid rails with different microalloying elements at a cooling rate of 1℃/s and deformation of 80%to explore the influence of rare-ea... We performed thermal simulation experiments of double-pass deformation of hypereutectoid rails with different microalloying elements at a cooling rate of 1℃/s and deformation of 80%to explore the influence of rare-earth and microalloying elements on the structure of hypereutectoid rails and optimize the composition design of hypereutectoid rails.Scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and other characterization techniques were employed to quantitatively analyzed the effects of different microalloying elements,including rare-earth elements,on pearlite lamellar spacing,cementite characteristics,and dislocation density.It was found that the lamellar spacing was reduced by adding various microalloying elements.Cementite lamellar thickness decreased with the refinement of pearlite lamellar spacing while the cementite content per unit volume increased.Local cementite spheroidization,dispersed in the ferrite matrix in granular form and thus playing the role of dispersion strengthening,was observed upon adding cerium(Ce).The contributions of dislocation density to the alloy strength of four steel sheet samples with and without the addition of nickel,Ce,and Ce–copper(Cu)composite were 26,27,32,and 37 MPa,respectively,indicating that the Ce–Cu composite had the highest dislocation strengthening effect.The Ce–Cu composite has played a meaningful role in the cementite characteristics and dislocation strengthening,which provides a theoretical basis for optimizing the composition design of hypereutectoid rails in actual production conditions. 展开更多
关键词 microalloying elements rare earth hypereutectoid rail CEMENTITE DISLOCATION
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Construction of a transposase accessible chromatin landscape reveals chromatin state of repeat elements and potential causal variant for complex traits in pigs
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作者 Tao Jiang Ziqi Ling +8 位作者 Zhimin Zhou Xiaoyun Chen Liqing Chen Sha Liu Yingchun Sun Jiawen Yang Bin Yang Jianzhen Huang Lusheng Huang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第2期529-545,共17页
Background:A comprehensive landscape of chromatin states for multiple mammalian tissues is essential for elucidating the molecular mechanism underlying regulatory variants on complex traits.However,the genome-wide chr... Background:A comprehensive landscape of chromatin states for multiple mammalian tissues is essential for elucidating the molecular mechanism underlying regulatory variants on complex traits.However,the genome-wide chromatin accessibility has been only reported in limited tissue types in pigs.Results:Here we report a genome-wide landscape of chromatin accessibility of 20 tissues in two female pigs at ages of 6 months using ATAC-seq,and identified 557,273 merged peaks,which greatly expanded the pig regulatory ele-ment repository.We revealed tissue-specific regulatory elements which were associated with tissue-relevant biologi-cal functions.We identified both positive and negative significant correlations between the regulatory elements and gene transcripts,which showed distinct distributions in terms of their strength and distances from corresponding genes.We investigated the presence of transposable elements(TEs)in open chromatin regions across all tissues,these included identifications of porcine endogenous retroviruses(PERVs)exhibiting high accessibility in liver and homology of porcine specific virus sequences to universally accessible transposable elements.Furthermore,we prior-itized a potential causal variant for polyunsaturated fatty acid in the muscle.Conclusions:Our data provides a novel multi-tissues accessible chromatin landscape that serve as an important resource for interpreting regulatory sequences in tissue-specific and conserved biological functions,as well as regula-tory variants of loci associated with complex traits in pigs. 展开更多
关键词 Chromatin accessibility Pig Tissue specific TRANSCRIPTOME Transposable elements
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Spatio-temporal variation of trace elements distributed over surface water of Upper Ganga River Basin in Western Himalayan Region
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作者 Deepika DIMRI Ambika KUMAR +1 位作者 DeepakKumar MISHRA Archana SHARMA 《Journal of Mountain Science》 SCIE CSCD 2023年第1期145-162,共18页
The rivers draining from the Himalayan range distribute enormous amount of fresh water to the people living in downstream regions.Trace metals flowed with river water can lead to serious impact on ecological system an... The rivers draining from the Himalayan range distribute enormous amount of fresh water to the people living in downstream regions.Trace metals flowed with river water can lead to serious impact on ecological system and human health.Nevertheless,the documentation on trace elements of Himalayan rivers is inadequately documented.The current study deals with the spatial and temporal variability of the major and trace elements of Ganga river water in epirhithron,metarhithron and hyporhithron zone belonging to Himalayan segment.Water samples from nineteen monitoring locations were collected in pre-monsoon(May-June),monsoon(AugustSeptember)and post-monsoon(December)seasons and subjected to be assessed for 20 elements(Ag,Al,Ba,Cd,Ca,Cr,Cu,Fe,Ga,K,Mn,Mg,Na,Ni,Pb,Sr,Th,U,Zn,and Zr)using ICP-OES(Inductively Coupled Plasma-Optical Emission Spectrometer).Different water pollution indexes such as HPI(Heavy Metal Pollution Index),MI(Metal Index)and PI(Pollution Index)were used to describe current water quality status at each monitoring station under particular classified ecological zone.The studied stations in hyporhithron zone had the value of Metal Index(MI>1),indicating threshold of warning.Further,the highest values of HPI in hyporhithron zone correspond to poor water quality status.Sites with poor water quality were also found to be contaminated as per the Pollution Index(PI),exhibiting high concentrations for element(Fe).However,the epirhithron and metarhithron zone in Himalayan segment showed excellent water quality mainly contributed from natural sources.Cluster Analysis(CA)and Principal Component Analysis(PCA)were applied to identify the main influential sources for Ganga river water pollution.The Kriging interpolation method was also applied to prepare spatial distribution map of computed indexes(HPI,MI,and PI).With the help of index of local Moran’s I(LMI),identified spatial clusters and spatial outliers revealed the elevated concentration of most elements in hyporhithron zone.The dataset presented in this study would be convenient for government officials in developing more effective management policies and necessary steps to check and monitor the Ganga river water quality.It was also suggested that further investigations in terms of trace elemental sources and their role in self-purification properties of Ganga water can be addressed in future. 展开更多
关键词 Trace elements Spatial variation Temporal variation Surface water Ganga River Basin ICP-OES
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Hierarchical pattern recognition of landform elements considering scale adaptation
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作者 XU Yue-xue ZHU Hong-chun +1 位作者 LI Jin-yu ZHANG Sheng-jia 《Journal of Mountain Science》 SCIE CSCD 2023年第7期2003-2014,共12页
Landform elements with varying morphologies and spatial arrangements are recognized as feature indicator of landform classification and play a critical role in geomorphological studies.Differential geometry method has... Landform elements with varying morphologies and spatial arrangements are recognized as feature indicator of landform classification and play a critical role in geomorphological studies.Differential geometry method has been extensively applied in prior landform element research,while its efficacy in differentiating similar morphological characteristics remains inadequate to date.To reduce reliance on geomorphometric variables and increase awareness of landform patterns,geomorphons method was generated in previous study corresponding to specific landform reclassification map based on lookup table.Besides,to address the problem of feature similarity,hierarchical classification was proposed and effectively utilized for terrain recognition through the analytical strategy of fuzzy gradient features.Thus,combining the advantages of these two aspects,a hierarchical framework was proposed in this study for landform element pattern recognition considering the morphology and hierarchy factors.First,the local triplet patterns derived from geomorphons were enhanced by setting the flatness threshold,and subsequently adopted for the primary landform element recognition.Then,as geomorphic units with the same morphology possess different spatial analytical scales,the unidentified landform elements under the principle of scale adaptation were determined by calculating the spatial correlation and entropy information.To ensure the effectiveness of this proposed method,the sampling points were randomly selected from NASADEM data and then validated against a real 3D terrain model.Quantitative results of landform element pattern recognition demonstrate that our approach can reach above 77%average accuracy.Additionally,it delineates local details more effectively than geomorphons in visual assessment,resulting in a 7%accuracy improvement in overall scale. 展开更多
关键词 DEM Landform elements Hierarchical classification Scale adaptation Pattern recognition
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Distribution and geochemical significance of trace elements in kerogens from Ediacaran–Lower Cambrian strata in South China
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作者 Qian Deng Guanyu Zhao +2 位作者 Haozhe Wang Bin Cheng Zewen Liao 《Acta Geochimica》 EI CAS CSCD 2023年第1期50-62,共13页
Some trace elements(TEs),both bio-essential and redox-sensitive,are promising tracers of Earth’s surface processes.As an essential sedimentary organic matter,kerogen may have inherited and retained the key TEs from o... Some trace elements(TEs),both bio-essential and redox-sensitive,are promising tracers of Earth’s surface processes.As an essential sedimentary organic matter,kerogen may have inherited and retained the key TEs from organisms.In this study,the distribution of TEs in kerogens from two sections(Dongkanshang and Fengtan) in South China was analyzed to explore its biogeochemical significance during Ediacaran-Lower Cambrian.Compared with V and Zn,the relative concentrations of Co,Ni,Cu,and Mo were generally higher in kerogens than in the whole rocks.Enrichment of TEs in the kerogen was involved in the selective utilization of TEs by different organic precursors and the competition of sulfide in the depositional environment.The significant content of TEs in the kerogens from deep-water facies corresponded to a more negative δ^(13) Ckeras a result of the dominant taxa of chemo autotrophs with tremendous bioaccumulation potential for trace metals and the reduction conditions favorable for organic matter preservation.Furthermore,the content variations of trace elements in the kerogens coincided with the rise and fall of the Ediacaran biota,implying that the trace elements might have played an important role in early life evolution. 展开更多
关键词 Trace elements KEROGEN Ediacaran-Early Cambrian Biogeochemical significance South China
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