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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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Assessing healthcare workers’knowledge and confidence in the diagnosis,management and prevention of Monkeypox
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作者 Epipode Ntawuyamara Thierry Ingabire +3 位作者 Innocent Yandemye Polycarpe Ndayikeza Bina Bhandari Yan-Hua Liang 《World Journal of Clinical Cases》 SCIE 2025年第1期38-47,共10页
BACKGROUND Monkeypox(Mpox),is a disease of global public health concern,as it does not affect only countries in western and central Africa.AIM To assess Burundi healthcare workers(HCWs)s’level of knowledge and confid... BACKGROUND Monkeypox(Mpox),is a disease of global public health concern,as it does not affect only countries in western and central Africa.AIM To assess Burundi healthcare workers(HCWs)s’level of knowledge and confidence in the diagnosis and management of Mpox.METHODS We conducted a cross-sectional study via an online survey designed mainly from the World Health Organization course distributed among Burundi HCWs from June-July 2023.The questionnaire comprises 8 socioprofessional-related questions,22 questions about Mpox disease knowledge,and 3 questions to assess confidence in Mpox diagnosis and management.The data were analyzed via SPSS software version 25.0.A P value<0.05 was considered to indicate statistical significance.RESULTS The study sample comprised 471 HCWs who were mainly medical doctors(63.9%)and nurses(30.1%).None of the 22 questions concerning Mpox knowledge had at least 50%correct responses.A very low number of HCWs(17.4%)knew that Mpox has a vaccine.The confidence level to diagnose(21.20%),treat(18.00%)or prevent(23.30%)Mpox was low among HCWs.The confidence level in the diagnosis of Mpox was associated with the HCWs’age(P value=0.009),sex(P value<0.001),work experience(P value=0.002),and residence(P value<0.001).The confidence level to treat Mpox was significantly associated with the HCWs’age(P value=0.050),sex(P value<0.001),education(P value=0.033)and occupation(P value=0.005).The confidence level to prevent Mpox was associated with the HCWs’education(P value<0.001),work experience(P value=0.002),residence(P value<0.001)and type of work institution(P value=0.003).CONCLUSION This study revealed that HCWs have the lowest level of knowledge regarding Mpox and a lack of confidence in the ability to diagnose,treat or prevent it.There is an urgent need to organize continuing medical education programs on Mpox epidemiology and preparedness for Burundi HCWs.We encourage future researchers to assess potential hesitancy toward Mpox vaccination and its associated factors. 展开更多
关键词 MONKEYPOX Public health emergency of international concern Healthcare workers EPIDEMIC PREPAREDNESS knowledge CONFIDENCE
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ON POTENT ELEMENTS AND PSEUDO CLEAN RINGS
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作者 DING Yan GAO Han-peng +2 位作者 LIU Xin-yi YAN Zi-yi ZHANG Ting 《数学杂志》 2025年第1期39-47,共9页
In this paper,potent index of an element and pseudo clean rings are considered.Some properties and examples of pseudo clean rings are given.We also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings... In this paper,potent index of an element and pseudo clean rings are considered.Some properties and examples of pseudo clean rings are given.We also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings are clean.Furthermore,we prove pseudo clean rings are directly finite and have stable range one. 展开更多
关键词 clean rings strongly J-clean rings pseudo clean rings potent elements
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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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Landscape Planning and Design of Folk Culture Block Based on Theory of Three Elements of Landscape
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作者 吴忠军 胡林波 梁莉清 《Journal of Landscape Research》 2010年第9期24-28,共5页
This paper firstly defined the concept of folk culture block,and then analyzed the significance and planning principle of landscape design in folk culture block,and at last expounded landscape planning and design of f... This paper firstly defined the concept of folk culture block,and then analyzed the significance and planning principle of landscape design in folk culture block,and at last expounded landscape planning and design of folk culture block based on theory of three elements of landscape. 展开更多
关键词 THEORY of three elements of LANDSCAPE FOLK culture BLOCK LANDSCAPE planning and design
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Computing of the Anchor by the Method of Three-Dimension Point-Radiate Infinite Elements 被引量:8
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作者 王艳芬 王元汉 谢洪阳 《Journal of China University of Geosciences》 SCIE CSCD 2007年第2期185-190,共6页
On the basis of the one-dimension infinite element theory, the coordinate translation and shape function of 3D point-radiate 8-node and 4-node infinite elements are derived. They are coupled with 20-node and 8-node fi... On the basis of the one-dimension infinite element theory, the coordinate translation and shape function of 3D point-radiate 8-node and 4-node infinite elements are derived. They are coupled with 20-node and 8-node finite elements to compute the compression distortion of the prestressed anchorage segment. The results indicate that when the prestressed force acts on the anchorage head and segment, the stresses and the displacements in the rock around the anchorage head and segment concentrate on the zone center with the anchor axis, and they decrease with exponential forms. Therefore,the stresses and the displacement spindles are formed. The calculating results of the infinite element are close to the theoretical results. This indicates the method is right. This article introduces a new way to study the mechanism of prestressed anchors. The obtained results have an important role in the research of the anchor mechanism and engineering application. 展开更多
关键词 infinite element prestressed anchor COUPLE finite element
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Characteristics of mineral elements in shoots of three annual halophytes in a saline desert, Northern Xinjiang 被引量:4
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作者 Ke ZHANG ChunJian LI +3 位作者 ZhongShao LI FuHai ZHANG ZhenYong ZHAO ChangYan TIAN 《Journal of Arid Land》 SCIE CSCD 2013年第2期244-254,共11页
Halophytes are valuable salt-, alkali- and drought-resistant germplasm resources. However, the char- acteristics of mineral elements in halophytes have not been investigated as intensively as those in crops. This stud... Halophytes are valuable salt-, alkali- and drought-resistant germplasm resources. However, the char- acteristics of mineral elements in halophytes have not been investigated as intensively as those in crops. This study attempted to investigate the characteristics of mineral elements for annual halophytes during their growth period to reveal their possible physiological mechanisms of salt resistance. By using three native annual halophytes (Salsola subcrassa, Suaeda acuminate and Petrosimonia sibirica) distributed in the desert in Northern Xinjiang of China, the dynamic changes in the mineral element contents of annual halophytes were analyzed through field sampling and laboratory analyses. The results demonstrated that the annual halophytes were able to absorb water and mineral nutrients selectively. In the interaction between the annual halophytes and saline soil, the adaptability of the annual halophytes was manifested as the accumulation of S, Na and CI during the growth period and maintenance of water and salt balance in the plant, thus ensuring their selective absorption of N, P, K, Ca, Mg and other mineral nutrients according to their growth demand. By utilizing this property, halophyte planting and mowing (before the wilting and death periods) could bioremediate heavy saline-alkali soil. 展开更多
关键词 annual halophyte mineral elements DESERT saline-alkali soil Northern Xinjiang
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The application of three-dimensional seismic spectral decomposition and semblance attribute to characterizing the deepwater channel depositional elements in the Taranaki Basin of New Zealand 被引量:3
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作者 LI Quan WU Wei +4 位作者 YU Shui KANG Hongquan TONG Liqing CAO Xiangyang LIU Xiaolong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第9期79-86,共8页
In the past few years, three-dimensional(3-D) seismogram has become an essential tool for the interpretation of subsurface stratigraphy and depositional systems. Seismic stratigraphy in conjunction with seismic geom... In the past few years, three-dimensional(3-D) seismogram has become an essential tool for the interpretation of subsurface stratigraphy and depositional systems. Seismic stratigraphy in conjunction with seismic geomorphology has elevated the degree to which seismic data can facilitate geological interpretation, especially in a deepwater environment. Technologies such as time slicing and interval attribute analysis can enhance geomorphological interpretations, and, when integrated with stratigraphic analyses, can yield insights regarding distribution of seal and reservoir facies. Multiple attributes corendering can further bring out features of geological interest that other technologies may overlook. This method involves corender spectral decomposition components(SDC) with semblance attributes to describe the distribution of deepwater channel elements and the boundaries of deepwater sinuous channel. Applying this technology to four elements is observed:(1) point-bars,(2) migration of channel meander loops,(3) channel erosion/cut, and(4) avulsion. The planview expression of the deepwater channel ranges from low sinuosity to high sinuosity. Furthermore, this technology has enabled interpreters to visualize details of complex depositional elements and can be used to predict net-to-gross ratio in channel systems, which can be incorporated into borehole planning for exploration as well as development needs to improve risk management significantly. The technology is applied to the study area in an effort to illustrate the variety of interpretation technologies available to the geoscientist. 展开更多
关键词 deepwater channel spectral decomposition semblance depositional elements deepwater Taranaki Basin
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Modelling of the relationship between trace elements and three species of sulfur in coal 被引量:1
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作者 Lu Xiao hua, Zeng Han cai National Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China Wei Lu xian Center of Microanalysis, Wuhan University of Automobile Industry, Wuhan, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第2期89-95,共7页
Based on the determination of several trace elements in coal particulate of different specific gravity, three variables regression equations relate the contents of trace elements Be, Cd, Co, Pb, Cu, Ni, As and three ... Based on the determination of several trace elements in coal particulate of different specific gravity, three variables regression equations relate the contents of trace elements Be, Cd, Co, Pb, Cu, Ni, As and three species of sulfur in coal were well established. For elements Cd, Co, Pb, Cu and Ni, the regression equations were successfully used for prediction of these trace elements in individual part of coal with different specific gravity. Factor analysis was also used to analyze the data sets. The results showed that a three factor model can interpret the data sets reasonably. Trace elements Cd, Co, Pb, Cu, Ni, inorganic sulfide and total sulfur in coal are high correlated with the first factor. Trace elements Be, sulfate and organic sulfide are high correlated with the second factor and trace elements Cr and As are high correlated with the third factor. The factors can be interpreted by the chemical properties of these elements. 展开更多
关键词 trace elements COAL regression analysis factor analysis.
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Enhancement Effects of Three Rare Earth Elements on the Growth of Chaetoceros Mulleri 被引量:1
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作者 Qu Keming(曲克明) +1 位作者 Xin Fuyan(辛福言) 《Marine Science Bulletin》 CAS 2001年第2期83-88,共6页
Enhancement effects of rare earth elements on the growth of Chaetoceros mulleri is studied in this paper. The results show that all of the light, middle and heavy rare earth elements have similar enhancement effect on... Enhancement effects of rare earth elements on the growth of Chaetoceros mulleri is studied in this paper. The results show that all of the light, middle and heavy rare earth elements have similar enhancement effect on the growth of Chaetoceros mulleri, with the beneficial concentrations of La, Gd and Yb being 7.28~87.40 μ mol/L, 6.36~57.23 μ mol/L and 5.78~17.34 μ mol/L. The optimum concentrations of La, Gd and Yb are 7.28 ~50.98 μ mol/L,31.80~44.52 μ m ol/L and 5.78~17.34 1μ mol/L, respectively. When the concentrations of La, Gd and Yb are 7.28~87.40 μ mol/L, 6.36~57.23 μ mol/L and 5.78~ 17,34 μ mol/L, the concentrations of chlorophyll have increased by 9.3~47.0%, 33.4~44.3%, and 36.5~40.3%, respectively as compared with the control group. The mechanism of enhancement of rare earth elements on the growth ot Chaetoceros mulleri is also discussed in this paper. 展开更多
关键词 RARE EARTH element CHAETOCEROS mulleri ENHANCEMENT
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Research on Knowledge-based Connecting Elements Modeling
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作者 HUANG Xiang, YAN Chong-jing (College of Mechanical and Electrical Engineering, Nanjing University o f Aeronautics and Astronautics, Nanjing 210016, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期162-163,共2页
Steps of manipulation is required to complete the m od eling of the connection elements such as bolt, pin and the like in commerce CAD system. It leads to low efficiency, difficulty to assure the relative position, im... Steps of manipulation is required to complete the m od eling of the connection elements such as bolt, pin and the like in commerce CAD system. It leads to low efficiency, difficulty to assure the relative position, impossibility to express rules and knowledge. Based on the inner character analy sis of interpart, detail modification and assembly relation of mechanical connec ting element, the idea, which extends the feature modeling of part to the interp art feature modeling for assembly purpose, is presented, and virtual part based connecting element modeling is proposed. Virtual part is a complement set of lo cal modification of part to be connected. In assembly modeling, base part is mod ified by Boolean operation between base part and virtual part. The modeling and assembly is finished just in one operation, at the same time the rules and knowl edge of the connection elements are encapsulated through virtual part. According to this mechanism, a knowledge-based connecting elements rapid design module i s developed on commerce software package UG with satisfying results. 展开更多
关键词 CAD knowledge-based engineering ASSEMBLY conn ecting element
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Assessment of toxicology knowledge in the fourth-year medical students:Three years of data
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作者 Jennie Buchanan Daniel Windels +1 位作者 Jeffrey Druck Kennon Heard 《World Journal of Emergency Medicine》 SCIE CAS 2018年第3期191-194,共4页
BACKGROUND:Pharmacology and toxicology are core content knowledge for physicians.Medical students should demonstrate understanding of general pharmacology and basic treatment of poisoning.The objective of this study w... BACKGROUND:Pharmacology and toxicology are core content knowledge for physicians.Medical students should demonstrate understanding of general pharmacology and basic treatment of poisoning.The objective of this study was to measure the knowledge of the 4th-year medical students(MS4)on these topics over 3 years.METHODS:A multiple-choice exam(15 questions)was administered to MS4 students in spring of 2010,2011,and 2012.Questions were developed by medical toxicologists to evaluate basic knowledge in three areas:pharmacologic effects(PE),treatment of poisoning(TOP),and pharmacokinetics(PK).The students were grouped by intended specialtiesinto pharmacologic intense(anesthesia,emergency medicine,internal medicine,pediatrics,and psychiatry),less pharmacologic intense specialties(dermatology,OB/GYN,ophthalmology,pathology,physical medicine and rehabilitation,radiology,and surgery)and by completion of a pharmacology or toxicology elective.Mean group scores were compared using ANOVA.RESULTS:Totally 332 of 401(83%)students completed the survey.Mean scores were stable over the three years,higher for students completing a toxicology rotation and for students entering a pharmacologically intense specialty.CONCLUSION:The external validity is limited to a single medical school with incomplete participation and content was limited by the survey length.Consistent results over the three-year period and correlation of performance with completing a toxicology rotation and intent to enter a pharmacology intensive specialty suggest this survey may correlate with toxicology knowledge.Implementation of required core courses focused on toxicology may improve core content knowledge in fourth year medical students. 展开更多
关键词 Medical STUDENT Education TOXICOLOGY knowledge
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Heterogeneous Image Knowledge Driven Visual Perception 被引量:1
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作者 Lan Yan Wenbo Zheng Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期255-257,共3页
Dear Editor,This letter is concerned with visual perception closely related to heterogeneous images.Facing the huge challenge brought by different image modalities,we propose a visual perception framework based on het... Dear Editor,This letter is concerned with visual perception closely related to heterogeneous images.Facing the huge challenge brought by different image modalities,we propose a visual perception framework based on heterogeneous image knowledge,i.e.,the domain knowledge associated with specific vision tasks,to better address the corresponding visual perception problems. 展开更多
关键词 VISUAL VISUAL knowledge
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Three-Tier Knowledge Management System Based on .NET
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作者 Mingxing Cai Jintao Zheng +1 位作者 Ping Shi Xiaohui Li 《Journal of Software Engineering and Applications》 2009年第1期40-43,共4页
Three-tier knowledge management system based on .NET architecture is designed according to requirement specification, characteristics of and relationship between enterprise electronic archives and knowledge management... Three-tier knowledge management system based on .NET architecture is designed according to requirement specification, characteristics of and relationship between enterprise electronic archives and knowledge management. This system using three-tier design based on factory pattern has good encapsulation and portability, with clearer and more concise structure. It degrades the costs of system development and maintenance and upgrades system’s high reusability and development efficiency. 展开更多
关键词 knowledge MANAGEMENT .NET three-Tier ARCHITECTURE Design Based on FACTORY PATTERN
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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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Low-Cost Federated Broad Learning for Privacy-Preserved Knowledge Sharing in the RIS-Aided Internet of Vehicles 被引量:1
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作者 Xiaoming Yuan Jiahui Chen +4 位作者 Ning Zhang Qiang(John)Ye Changle Li Chunsheng Zhu Xuemin Sherman Shen 《Engineering》 SCIE EI CAS CSCD 2024年第2期178-189,共12页
High-efficiency and low-cost knowledge sharing can improve the decision-making ability of autonomous vehicles by mining knowledge from the Internet of Vehicles(IoVs).However,it is challenging to ensure high efficiency... High-efficiency and low-cost knowledge sharing can improve the decision-making ability of autonomous vehicles by mining knowledge from the Internet of Vehicles(IoVs).However,it is challenging to ensure high efficiency of local data learning models while preventing privacy leakage in a high mobility environment.In order to protect data privacy and improve data learning efficiency in knowledge sharing,we propose an asynchronous federated broad learning(FBL)framework that integrates broad learning(BL)into federated learning(FL).In FBL,we design a broad fully connected model(BFCM)as a local model for training client data.To enhance the wireless channel quality for knowledge sharing and reduce the communication and computation cost of participating clients,we construct a joint resource allocation and reconfigurable intelligent surface(RIS)configuration optimization framework for FBL.The problem is decoupled into two convex subproblems.Aiming to improve the resource scheduling efficiency in FBL,a double Davidon–Fletcher–Powell(DDFP)algorithm is presented to solve the time slot allocation and RIS configuration problem.Based on the results of resource scheduling,we design a reward-allocation algorithm based on federated incentive learning(FIL)in FBL to compensate clients for their costs.The simulation results show that the proposed FBL framework achieves better performance than the comparison models in terms of efficiency,accuracy,and cost for knowledge sharing in the IoV. 展开更多
关键词 knowledge sharing Internet of Vehicles Federated learning Broad learning Reconfigurable intelligent surfaces Resource allocation
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Basic Elements Knowledge Acquisition Study in the Chinese Character Intelligent Formation System
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作者 Mingyou LIU Chengsen DUAN Youguo PI 《Journal of Software Engineering and Applications》 2009年第5期316-322,共7页
In the Chinese character intelligent formation system without Chinese character library, it is possible that the same basic element in different Chinese characters is different in position, size and shape. The geometr... In the Chinese character intelligent formation system without Chinese character library, it is possible that the same basic element in different Chinese characters is different in position, size and shape. The geometry transformation from basic elements to the components of Chinese characters can be realized by affine transformation, the transformation knowledge acquisition is the premise of Chinese character intelligent formation. A novel algorithm is proposed to ac-quire the affine transformation knowledge of basic elements automatically in this paper. The interested region of Chi-nese character image is determined by the structure of the Chinese character. Scale invariant and location invariant of basic element and Chinese character image are extracted with SIFT features, the matching points of the two images are determined according to the principle of Minimum Euclidean distance of eigenvectors. Using corner points as identifi-cation features, calculating the one-way Hausdorff distance between corner points as the similarity measurement from the affine image to the Chinese character sub-image, affine coefficients are determined by optimal similarity. 70244 Chinese characters in National Standards GB18030-2005 character set are taken as the experimental object, all the characters are performed and the experimental courses and results are presented in this paper. 展开更多
关键词 Chinese CHARACTER INTELLIGENT FORMATION knowledge Acquisition AFFINE Transformation HAUSDORFF Distance
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The spatial temporal evolution characteristics of the load/unload response ratio(LURR) and its implications for predicting the three elements of earthquakes
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作者 宋治平 尹祥础 陈学忠 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第2期235-244,共10页
The spatial temPOral evolution characteristics of the load/unload response ratio (Y) before strong earthquakes is studied in this paper. The results show that the regions of high value of Y migrate and converge to the... The spatial temPOral evolution characteristics of the load/unload response ratio (Y) before strong earthquakes is studied in this paper. The results show that the regions of high value of Y migrate and converge to the impending earthquake epicenter from different directions before the occurrence of the event. Basing on this discovery, it is proposed that the method can be used to predict the three elements of an earthquake. It was applied to predict that an earthquake would occur in the western part of Yunnan Province, southwestern China. The three elements (time, space and magnitude) of the Menglian earthquake with Ms7.3 which occurred on July 12, 1995 in Yunnan Province tallied with our prediction. 展开更多
关键词 load/unload resPOnse ratio (LURR ) time-space evolution of LURR three elements of earthquakes earthquake prediction.
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Parametric Modeling of Static Three-Dimensional Problem of Buried Pipeline through the Coupling between a Finite Cylindrical Shell Element and Special Boundary Elements
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作者 Raimundo A. Menezes Junior Moises M. Salvino +4 位作者 Carlos L. dos Santos Allan R. Albuquerque Jailson M.Ferreira Dawy Keyson Carlo R. Lima Martin 《Journal of Civil Engineering and Architecture》 2015年第6期701-714,共14页
This work deals with an application in parametric modeling of problems regarding pipelines buried in static system, written in C++ using ObjectARX functions. The application is fully integrated with AutoCAD through ... This work deals with an application in parametric modeling of problems regarding pipelines buried in static system, written in C++ using ObjectARX functions. The application is fully integrated with AutoCAD through saproms.dll and saproms.arx libraries where the stages of pre-processing, processing and post-processing are done in AutoCAD sotlware environment itself without having to export data to another processing environment. The analysis processing is done by functions whose algorithms are based on the solution of the coupling between the FEM (finite element method) and the BEM (boundary element method). The representation of the homogeneous pipeline is made by the FEM using a finite element in the form of a cylindrical panel called CYS (cylindrical shell), developed from the homogeneous isotropic model proposed initially by Djoudi Bahai, who uses the philosophy of the assumed deformation model (assumed strain based model). The soil is taken to be a continuum infinite or semi-infinite elastic solid patterned by BEM where special boundary elements are proposed with curved surface or curved edges to represent the soil-structure interaction mainly in the areas of contact with the pipeline. 展开更多
关键词 Finite elements boundary elements AUTOCAD
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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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