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Toward understanding the role of genomic repeat elements in neurodegenerative diseases
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作者 Zhengyu An Aidi Jiang Jingqi Chen 《Neural Regeneration Research》 SCIE CAS 2025年第3期646-659,共14页
Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage se... Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements. 展开更多
关键词 Alzheimer's disease ATAXIA deep learning long-read sequencing NEURODEGENERATION neurodegenerative diseases Parkinson's disease repeat element structural variant
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Identifying the Impact of Preconstruction Elements on Project Time Variances
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作者 Sogol Salary Matthew Reyes 《Journal of Civil Engineering and Architecture》 2025年第1期9-21,共13页
Working toward an efficient duration and timeline for the preconstruction phase should be one of the main objectives for project owners.Failing to plan for and coordinate preconstruction decisions in order to control ... Working toward an efficient duration and timeline for the preconstruction phase should be one of the main objectives for project owners.Failing to plan for and coordinate preconstruction decisions in order to control preconstruction duration and manage time variances can lead to financial insecurities,incomplete contract documents,permitting issues,and unrealistic schedules and resource allocation during this phase.To minimize time variances and ensure a productive decision-making process,project owners should be familiar with critical elements in a project that cause variances in the preconstruction phase timeline.In this study,the impacts of eleven critical preconstruction elements on time variances were analyzed.These eleven preconstruction elements are considered critical in how they impact time variances during the preconstruction phase.They were determined to be critical based either on significantly impacting time variance during the preconstruction phase or believed to be critical from findings from previous studies,however,the findings from this study showed no significant impact on the time variances.In most previous studies focusing on the elements impacting project schedules,data were collected by surveying construction professionals.In this study,objective and quantitative data related to project preconstruction elements were used as opposed to self-reported data.Using the results of this study,project owners and stakeholders will be able to evaluate the critical preconstruction elements impacting the timing of their projects and prioritize decisions related to the critical elements early on during the preconstruction phase. 展开更多
关键词 Preconstruction time variances critical preconstruction elements objective data.
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Recent progress on elemental tellurium and its devices
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作者 Jiachi Liao Zhengxun Lai +1 位作者 You Meng Johnny C.Ho 《Journal of Semiconductors》 2025年第1期91-106,共16页
The rapid advancement of information technology has heightened interest in complementary devices and circuits.Conventional p-type semiconductors often lack sufficient electrical performance,thus prompting the search f... The rapid advancement of information technology has heightened interest in complementary devices and circuits.Conventional p-type semiconductors often lack sufficient electrical performance,thus prompting the search for new materials with high hole mobility and long-term stability.Elemental tellurium(Te),featuring a one-dimensional chiral atomic structure,has emerged as a promising candidate due to its narrow bandgap,high hole mobility,and versatility in industrial applications,particularly in electronics and renewable energy.This review highlights recent progress in Te nanostructures and related devices,focusing on synthesis methods,including vapor deposition and hydrothermal synthesis,which produce Te nanowires,nanorods,and other nanostructures.Critical applications in photodetectors,gas sensors,and energy harvesting devices are discussed,with a special emphasis on their role within the internet of things(IoT)framework,a rapidly growing field that is reshaping our technological landscape.The prospects and potential applications of Te-based technologies are also highlighted. 展开更多
关键词 elemental tellurium PHOTODETECTOR field-effect transistor gas sensor energy harvesting device
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Integrating finite element analysis in total hip arthroplasty for childhood hip disorders:Enhancing precision and outcomes
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作者 Muhammad Imam Ammarullah 《World Journal of Orthopedics》 2025年第1期1-11,共11页
Total hip arthroplasty for adults with sequelae from childhood hip disorders poses significant challenges due to altered anatomy.The paper published by Oommen et al reviews the essential management strategies for thes... Total hip arthroplasty for adults with sequelae from childhood hip disorders poses significant challenges due to altered anatomy.The paper published by Oommen et al reviews the essential management strategies for these complex cases.This article explores the integration of finite element analysis(FEA)to enhance surgical precision and outcomes.FEA provides detailed biomechanical insights,aiding in preoperative planning,implant design,and surgical technique optimization.By simulating implant configurations and assessing bone quality,FEA helps in customizing implants and evaluating surgical techniques like subtrochanteric shortening osteotomy.Advanced imaging techniques,such as 3D printing,virtual reality,and augmented reality,further enhance total hip arthroplasty precision.Future research should focus on validating FEA models,developing patient-specific simulations,and promoting multidisciplinary collaboration.Integrating FEA and advanced technologies in total hip arthroplasty can improve functional outcomes,reduce complications,and enhance quality of life for patients with childhood hip disorder sequelae. 展开更多
关键词 Finite element analysis Total hip arthroplasty Childhood hip disorders IMPLANT BIOMECHANICAL
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Effects of spatial heterogeneity on pseudo-static stability of coal mine overburden dump slope,using random limit equilibrium and random finite element methods:A comparative study
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作者 Madhumita Mohanty Rajib Sarkar Sarat Kumar Das 《Earthquake Engineering and Engineering Vibration》 2025年第1期83-99,共17页
Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump mate... Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump materials is imperative for an adequate evaluation of the seismic stability of OB dump slopes.In this study,pseudo-static seismic stability analyses are carried out for an OB dump slope by considering the material parameters obtained from an insitu field investigation.Spatial heterogeneity is simulated through use of the random finite element method(RFEM)and the random limit equilibrium method(RLEM)and a comparative study is presented.Combinations of horizontal and vertical spatial correlation lengths were considered for simulating isotropic and anisotropic random fields within the OB dump slope.Seismic performances of the slope have been reported through the probability of failure and reliability index.It was observed that the RLEM approach overestimates failure probability(P_(f))by considering seismic stability with spatial heterogeneity.The P_(f)was observed to increase with an increase in the coefficient of variation of friction angle of the dump materials.Further,it was inferred that the RLEM approach may not be adequately applicable for assessing the seismic stability of an OB dump slope for a horizontal seismic coefficient that is more than or equal to 0.1. 展开更多
关键词 coal mine overburden dump slope random limit equilibrium method random finite element method seismic slope stability spatial heterogeneity
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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 被引量:1
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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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Investigation of the block toppling evolution of a layered model slope by centrifuge test and discrete element modeling 被引量:2
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作者 Leilei Jin Hongkai Dong +3 位作者 Fei Ye Yufeng Wei Jianfeng Liu Changkui Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期112-122,共11页
Primary toppling usually occurs in layered rock slopes with large anti-dip angles.In this paper,the block toppling evolution was explored using a large-scale centrifuge system.Each block column in the layered model sl... Primary toppling usually occurs in layered rock slopes with large anti-dip angles.In this paper,the block toppling evolution was explored using a large-scale centrifuge system.Each block column in the layered model slope was made of cement mortar.Some artificial cracks perpendicular to the block column were prefabricated.Strain gages,displacement gages,and high-speed camera measurements were employed to monitor the deformation and failure processes of the model slope.The centrifuge test results show that the block toppling evolution can be divided into seven stages,i.e.layer compression,formation of major tensile crack,reverse bending of the block column,closure of major tensile crack,strong bending of the block column,formation of failure zone,and complete failure.Block toppling is characterized by sudden large deformation and occurs in stages.The wedge-shaped cracks in the model incline towards the slope.Experimental observations show that block toppling is mainly caused by bending failure rather than by shear failure.The tensile strength also plays a key factor in the evolution of block toppling.The simulation results from discrete element method(DEM)is in line with the testing results.Tensile stress exists at the backside of rock column during toppling deformation.Stress concentration results in the fragmented rock column and its degree is the most significant at the slope toe. 展开更多
关键词 Block toppling CENTRIFUGE Anti-dip slope Failure mechanism Discrete element method
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Pig H3K4me3,H3K27ac,and gene expression profiles reveal reproductive tissue-specific activity of transposable elements 被引量:1
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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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Finite Element Analysis for Magneto-Convection Heat Transfer Performance in Vertical Wavy Surface Enclosure:Fin Size Impact 被引量:3
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作者 Md.Fayz-Al-Asad F.Mebarek-Oudina +3 位作者 H.Vaidya Md.Shamim Hasan Md.Manirul Alam Sarker A.I.Ismail 《Frontiers in Heat and Mass Transfer》 EI 2024年第3期817-837,共21页
The goal of this paper is to represent a numerical study of magnetohydrodynamic mixed convection heat transfer in a lid-driven vertical wavy enclosure with a fin attached to the bottomwall.We use a finite elementmetho... The goal of this paper is to represent a numerical study of magnetohydrodynamic mixed convection heat transfer in a lid-driven vertical wavy enclosure with a fin attached to the bottomwall.We use a finite elementmethod based on Galerkin weighted residual(GWR)techniques to set up the appropriate governing equations for the present flow model.We have conducted a parametric investigation to examine the impact of Hartmann and Richardson numbers on the flow pattern and heat transmission features inside a wavy cavity.We graphically represent the numerical results,such as isotherms,streamlines,velocity profiles,local and mean Nusselt numbers,and average surface temperature.Comparisons between the results of this work and previously published work in a literature review have been produced to examine the reliability and consistency of the data.The different sizes of the fin surface significantly impact flow creation and temperature fields.Additionally,the long fin size is necessary to enhance the heat transfer rate on the right surface at large Richardson numbers and low Hartmann numbers.Fin surfaces can significantly increase the mixing of fluid inside the enclosure,which can mean reductions in reaction times and operating costs,along with increases in heat transfer and efficiency. 展开更多
关键词 Fin surface finite element method combined convection MHD wavy enclosure
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Design of low-alloying and high-performance solid solution-strengthened copper alloys with element substitution for sustainable development 被引量:1
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作者 Jiaqiang Li Hongtao Zhang +2 位作者 Jingtai Sun Huadong Fu Jianxin Xie 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期826-832,共7页
Solid solution-strengthened copper alloys have the advantages of a simple composition and manufacturing process,high mechanical and electrical comprehensive performances,and low cost;thus,they are widely used in high-... Solid solution-strengthened copper alloys have the advantages of a simple composition and manufacturing process,high mechanical and electrical comprehensive performances,and low cost;thus,they are widely used in high-speed rail contact wires,electronic component connectors,and other devices.Overcoming the contradiction between low alloying and high performance is an important challenge in the development of solid solution-strengthened copper alloys.Taking the typical solid solution-strengthened alloy Cu-4Zn-1Sn as the research object,we proposed using the element In to replace Zn and Sn to achieve low alloying in this work.Two new alloys,Cu-1.5Zn-1Sn-0.4In and Cu-1.5Zn-0.9Sn-0.6In,were designed and prepared.The total weight percentage content of alloying elements decreased by 43%and 41%,respectively,while the product of ultimate tensile strength(UTS)and electrical conductivity(EC)of the annealed state increased by 14%and 15%.After cold rolling with a 90%reduction,the UTS of the two new alloys reached 576 and 627MPa,respectively,the EC was 44.9%IACS and 42.0%IACS,and the product of UTS and EC(UTS×EC)was 97%and 99%higher than that of the annealed state alloy.The dislocations proliferated greatly in cold-rolled alloys,and the strengthening effects of dislocations reached 332 and 356 MPa,respectively,which is the main reason for the considerable improvement in mechanical properties. 展开更多
关键词 element substitution copper alloy solid solution strengthening microstructure and performance
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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 被引量:1
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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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The abundance,distribution,and enrichment mechanism of harmful trace elements in coals from Guizhou,Southwestern China 被引量:1
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作者 Hui Hou Wei Cheng +1 位作者 Ruidong Yang Yan Zhang 《Acta Geochimica》 EI CAS CSCD 2024年第5期889-903,共15页
Coal seams can enrich a variety of harmful trace elements under specific geological conditions.The spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of eac... Coal seams can enrich a variety of harmful trace elements under specific geological conditions.The spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of each element content are different.The harmful elements released in the process of coal mining and utilization will cause serious harm to the environment and the human body.It is of great resource significance to study the geochemistry of coal that affects the enrichment and distribution characteristics of harmful trace elements.Based on the domestic and foreign literature on coal geochemistry in Guizhou published by previous investigators,this study counted 1097 sample data from 23 major coal-producing counties in Guizhou Province,systematically summarized the relevant research results of harmful trace elements in the coal of Guizhou,and revealed the overall distribution and enrichment characteristics of harmful trace elements in the coal of Guizhou.The results show that the average contents of Cd,Pb,Se,Cu,Mo,U,V,As,Hg,and Cr in coal of Guizhou are higher than those in Chinese coal and world coal.A variety of harmful trace elements in the coal of Guizhou have high background values,especially in Liupanshui,Xingyi and Qianbei coalfield.The enrichment of various harmful trace elements in the Late Permian coal in Guizhou is mainly related to the combined action of various geological and geochemical factors.The supply of terrigenous debris and sedimentary environment may be the basic background of the enrichment of harmful elements in western Guizhou,while low-temperature hydrothermal activity and volcanic ash deposition may be the main reasons for the enrichment of harmful elements in southwestern Guizhou. 展开更多
关键词 Harmful trace elements Distribution characteristics Enrichment law Geological and geochemical features GUIZHOU
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Research on Developing an Assessment Scale for Tourism Experience Elements of Ancient Shu Road Heritage Trail 被引量:1
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作者 Wang Yuan Wang Bo Zhou Jiang 《Contemporary Social Sciences》 2024年第5期118-142,共25页
Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse them... Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse thematic variations,and considerable tourist appeal,these paths have emerged as representative heritage trails,increasingly transforming into a novel tourism product experience that is highly favored by tourists and recognized by government authorities.However,research on ancient roads for tourism in China currently lacks a systematic theoretical framework,as well as relevant policies,regulations,and standards to guide their practical development.Therefore,there is a pressing need to draw upon international best practices and conduct foundational research to develop an experience element system that aligns with the perceptions,behaviors,and consumption characteristics of Chinese tourists,thereby advancing theoretical exploration in this field.This study focuses on the representative Ancient Shu Road as a case study and employs a mixed-method approach that integrates qualitative and quantitative research.It aims to construct a tourist-centric scale for the experience elements of ancient road tourism while analyzing the interactive relationship between these experience elements and tourist needs.This study addresses a significant gap in the development of indicator systems for domestic studies of ancient road tourism experiences.Ultimately,the study establishes a comprehensive scale that encompasses three core categories—trail resources and environment,facilities and services,and modes of tourism activities—along with eight primary dimensions:core resources,surrounding cultural environment,surrounding natural environment,tourism reception facilities and services,infrastructure and support services,information facilities and information services,and outdoor and recreational activities.This scale consists of thirty-two specific items,providing a robust reference for future research endeavors.Additionally,the study proposes specific development strategies related to key mechanisms,spatial configuration,and facility construction to enhance the overall development of ancient road tourism. 展开更多
关键词 ancient roads heritage trails tourism experience elements scale development
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Method to measure tree-ring width,density,elemental composition,and stable carbon and oxygen isotopes using one sample 被引量:1
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作者 Chenxi Xu Yaru Zhao +4 位作者 Wenling An Qingyu Zhao Yucheng Liu Masaki Sano Takeshi Nakatsuka 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期167-174,共8页
Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pret... Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pretreat-ment has been needed for each proxy.Here,we developed a method by which each proxy can be measured in the same sample.First,the sample is polished for ring width meas-urement.After obtaining the ring width data,the sample is cut to form a 1-mm-thick wood plate.The sample is then mounted in a vertical sample holder,and gradually scanned by an X-ray beam.Simultaneously,the count rates of the fluorescent photons of elements(for chemical characteriza-tion)and a radiographic grayscale image(for wood density)are obtained,i.e.the density and the element content are obtained.Then,cellulose is isolated from the 1-mm wood plate by removal of lignin,and hemicellulose.After producing this cellulose plate,cellulose subsamples are separated by knife under the microscope for inter-annual and intra-annual stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)analysis.Based on this method,RW,density,elemental composition,δ^(13)C,and δ^(18)O can be measured from the same sample,which reduces sample amount and treatment time,and is helpful for multi-proxy comparison and combination research. 展开更多
关键词 Tree-ring width Tree-ring density Tree-ring elemental composition Tree-ring stable carbon and oxygenisotopes
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Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China 被引量:1
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作者 DING Gaoming JI Genyuan +5 位作者 YAN Guolong XU Yongzhong WANG Kunming XIAO Chun WANG Quanle GUO Dongbao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期736-752,共17页
Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-di... Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking markers.The Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China Block.Abundant borehole data on oreforming elements underpin deep geochemical predictions.The methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration. 展开更多
关键词 3D geochemical model ore-forming elements GEOSTATISTICS deep mineralization prediction Yechangping Mo deposit
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A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics 被引量:1
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作者 Liang Wang Xue Zhang +1 位作者 Jingjing Meng Qinghua Lei 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2172-2183,共12页
In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated soils.Our approach incorporates the nodal integration technique into a gene... In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated soils.Our approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM formulation.To mitigate the volumetric locking issue in low-order elements,we employ a node-based strain smoothing technique.By discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the PFEM.We express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)problem.Stresses,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point method.Consequently,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM formulation.Numerical experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM approaches.This work holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics. 展开更多
关键词 Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)
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Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs 被引量:1
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作者 Lei Yang Baixi Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2960-2981,共22页
In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hy... In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hydraulic fractures in layered porous reservoirs with modulus contrast.The coupled hydromechanical model is first verified against an analytical solution and a laboratory experiment.Then,the fracture geometry(e.g.height,aperture,and area)and fluid pressure evolutions of multiple hydraulic fractures placed in a porous reservoir interbedded with alternating stiff and soft layers are investigated using the model.The stress and pore pressure distributions within the layered reservoir during fluid injection are also presented.The simulation results reveal that stress umbrellas are easily to form among multiple hydraulic fractures’tips when propagating in soft layers,which impedes the simultaneous height growth.It is also observed that the impediment effect of soft layer is much more significant in the fractures suppressed by the preferential growth of adjoining fractures.After that,the combined effect of in situ stress ratio and fracturing spacing on the multi-fracture height growth is presented,and the results elucidate the influence of in situ stress ratio on the height growth behavior depending on the fracture spacing.Finally,it is found that the inclusion of soft layers changes the aperture distribution of outmost and interior hydraulic fractures.The results obtained from this study may provide some insights on the understanding of hydraulic fracture height containment observed in filed. 展开更多
关键词 Hydraulic fracturing Layered reservoir Simultaneous height growth In situ stress Fracture spacing Extended finite element method(XFEM) Cohesive zone method(CZM)
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Repressor elements provide insights into tissue development and phenotypes in pigs
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作者 Yue-Dong Zhang Chao Guo +9 位作者 Hang Liu Yun Gao Yongjun Tan Longjian Niu Ligang Wang Lixian Wang David MIrwin Chunhui Hou Zhong-Yin Zhou Ya-Ping Zhang 《Zoological Research》 SCIE CSCD 2024年第6期1313-1326,共14页
Repressor elements significantly influence economically relevant phenotypes in pigs;however,their precise roles and characteristics are inadequately understood.In the present study,we employed H3K27me3 profiling,assay... Repressor elements significantly influence economically relevant phenotypes in pigs;however,their precise roles and characteristics are inadequately understood.In the present study,we employed H3K27me3 profiling,assay for transposase-accessible chromatin with highthroughput sequencing(ATAC-seq),and RNA sequencing(RNA-seq)data across six tissues derived from three embryonic layers to identify and map 2034 super repressor elements(SREs) and 22223 typical repressor elements(TREs) in the pig genome.Notably,many repressor elements were conserved across mesodermal and ectodermal tissues.SREs exhibited tight regulation of their target genes,affecting a limited number of genes within a specific genomic region with pronounced effects,while TREs exerted broader but weaker regulation over a wider range of target genes.Furthermore,in neuronal tissues,genes regulated by repressor elements started to be repressed during the differentiation of stem cells into progenitor cells.Notably,analysis showed that many repressor elements exhibited cooperative and additive effects on the modulation of KLF4 expression.This research provides the first comprehensive map of pig repressor elements,serving as an essential reference for future studies on repressor elements. 展开更多
关键词 Repressor elements Super repressor elements SILENCER Regulatory model Tissue development KLF4 Pig
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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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Emergence of a novel multi-resistance-mediating integrative and conjugative element ICEPmu3 in Pasteurella multocida
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作者 Jiao He Zhishuang Yang +15 位作者 Mingshu Wang Renyong Jia Shun Chen Mafeng Liu Xinxin Zhao Qiao Yang Ying Wu Shaqiu Zhang Juan Huang Xumin Ou Di Sun Bin Tian Yu He Zhen Wu Anchun Cheng Dekang Zhu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第11期3938-3942,共5页
Pasteurella multocida(PM)has been infecting a variety of hosts for a long time,causing sustained economic losses worldwide;however,there have been limited studies on its extensive adaptability(Aktories et al.2012).Ana... Pasteurella multocida(PM)has been infecting a variety of hosts for a long time,causing sustained economic losses worldwide;however,there have been limited studies on its extensive adaptability(Aktories et al.2012).Analysis of strains data collected in our laboratory revealed that PM typically acquires foreign genes through transformation and conjugation,rather than transformation and fusion.Integrative and conjugative elements(ICEs)are a crucial mechanism that leads to abrupt changes in niche preferences and enhances environmental adaptability for bacteria,with their number far exceeding the number of plasmids and phages(Wozniak and Waldor 2010;Johnson and Grossman 2015;Botelho and Schulenburg 2021).Previous research has shown that the European bovine-sourced strain Pm36950 contains the experimentally transferable resistant ICEPmu1,which could integrate into the host chromosome or forming a circular intermediate(Michael et al.2012).Additionally,a few studies have suggested that PM strains isolated from European bovine and Asian swine might contain ICEs,but these claims lack experimental verification(Klima et al.2014;Moustafa et al.2015;Kadlec et al.2017;Peng et al.2017;Beker et al.2018;Schink et al.2022).Currently,there is no data available on ICE-carrying PM strains isolated from hosts outside of European cattle or Chinses swine.This letter presents a report on a novel ICE identified in the hypervirulent and multidrug-resistant PM HN141014 strain isolated from Chinese duck.The ICE was specifically analyzed for its resistance genes,transferable capacity and host diversity. 展开更多
关键词 conjugative element EXCEEDING
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