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Genetic diversity of the S-type small subunit ribosomal RNA gene of Plasmodium knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia
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作者 Eric Tzyy Jiann Chong Joveen Wan Fen Neoh +3 位作者 Tiek Ying Lau Kek Heng Chua Yvonne Ai-Lian Lim Ping-Chin Lee 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第2期84-90,共7页
Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and hap... Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and haplotype.Methods:Thirty-nine blood samples infected with P.knowlesi were collected in Sabah,Malaysian Borneo and Peninsular Malaysia.The S-type SSU rRNA gene was amplified using polymerase chain reaction,cloned into a vector,and sequenced.The natural selection and haplotype of the S-type SSU rRNA gene sequences were determined using DnaSP v6 and illustrated using NETWORK v10.This study's 39 S-type SSU rRNA sequences and eight sequences from the Genbank database were subjected to phylogenetic analysis using MEGA 11.Results:Overall,the phylogenetic analysis showed no evidence of a geographical cluster of P.knowlesi isolates from different areas in Malaysia based on the S-type SSU rRNA gene sequences.The S-type SSU rRNA gene sequences were relatively conserved and with a purifying effect.Haplotype sharing of the S-type SSU rRNA gene was observed between the P.knowlesi isolates in Sabah,Malaysian Borneo,but not between Sabah,Malaysian Borneo and Peninsular Malaysia.Conclusions:This study suggests that the S-type SSU rRNA gene of P.knowlesi isolates in Sabah,Malaysian Borneo,and Peninsular Malaysia has fewer polymorphic sites,representing the conservation of the gene.These features make the S-type SSU rRNA gene suitable for comparative studies,such as determining the evolutionary relationships and common ancestry among P.knowlesi species. 展开更多
关键词 Plasmodium knowlesi s-type small subunit ribosomal RNA Genetic diversity Natural selection HAPLOTYPE
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Fiber cladding dual channel surface plasmon resonance sensor based on S-type fiber 被引量:1
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作者 魏勇 赵晓玲 +6 位作者 刘春兰 王锐 蒋天赐 李玲玲 石晨 刘纯彪 竺栋 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期187-195,共9页
Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an ... Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an S-shaped structure on the fiber to couple the light in the fiber core to the cladding.In this paper,the effects of fiber parameters on the performance of the sensor were studied by simulation and experiment.Based on the conclusion that the smaller the core diameter is,the closer the working band of the SPR resonance is to long wavelengths,and that the geometric characteristics mean that a multimode fiber can receive the fiber cladding light from a small core diameter few-mode fiber,a dual channel SPR sensor with a double S-type fiber cascade was proposed.In the refractive index detection range of 1.333–1.385refractive index units(RIU),the resonant working band of channel I is 627.66 nm–759.78 nm,with an average sensitivity of 2540.77 nm/RIU,and the resonant working band of channel II is 518.24 nm–658.2 nm,with an average sensitivity of2691.54 nm/RIU.The processing method for the S-type fiber cladding SPR sensor is simple,effectively solving the problem of this type of SPR sensor structure and the difficult realization of a dual channel.The sensor is expected to be used in the fields of medical treatment and biological analysis. 展开更多
关键词 surface plasmon resonance(SPR) s-type structure dual channel cladding fiber SPR sensor
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英国制造——捷豹XJ8和S-TYPE中国上市
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作者 孙磊 晓军 《汽车与驾驶维修》 2004年第7期12-14,共3页
虽然在世界汽车制造中,无论是汽车品牌的数量还是汽车的产销量,英国都难以与美国、日本、德国以及法国等相比。但是有一点不可否认,那就是英国在豪华车领域具有无与伦比的地位,像劳斯莱斯、宾利、罗孚、捷豹、阿斯顿·马丁以及... 虽然在世界汽车制造中,无论是汽车品牌的数量还是汽车的产销量,英国都难以与美国、日本、德国以及法国等相比。但是有一点不可否认,那就是英国在豪华车领域具有无与伦比的地位,像劳斯莱斯、宾利、罗孚、捷豹、阿斯顿·马丁以及莲花等。 展开更多
关键词 英国 捷豹XJ8 s-type 中国 汽车市场 市场推广 轿车 车型
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Genesis of S-type Granites in the Pengshan Sn-polymetallic Ore Field, Northern Jiangxi Province and its Implications 被引量:1
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作者 YIN Qingqing XIANG Xinkui +6 位作者 YU Zhendong YANG Xiufeng WANG Tianchen ZHONG Bo TAN Rong LIAO Jianhai ZHU Yuansong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第6期1860-1873,共14页
The Pengshan Sn-polymetallic ore field is located in the southeastern part of the Yangtze block,spanning the southeast edge of the MLYDZ and the northern edge of the mid-segment of the Jiangnan Uplift,and on one side ... The Pengshan Sn-polymetallic ore field is located in the southeastern part of the Yangtze block,spanning the southeast edge of the MLYDZ and the northern edge of the mid-segment of the Jiangnan Uplift,and on one side of the MLYDZ.The studies of LA-ICP-MS zircon U-Pb chronology and petrogeochemistry for Early Cretaceous acid granites from the Pengshan ore field were carried out in this paper.We report zircon U-Pb geochronology and whole-rock geochemistry for acid granites in the Pengshan ore field.The zircon U-Pb ages of the muscovite-granite,biotite adamellite and granite-porphyry are 127.6±1.7 Ma,126.9±1.6 Ma and 126.6±2.0 Ma,respectively.The granites in Pengshan are characterized by a high silicon content and are rich in alkali.They belong to high-potassium,calc-alkaline,peraluminous granite.The rocks have a relatively high Rb/Ba ratio,and the data points for muscovite-granite and biotite adamellite all fall within the clay-rich sources region,near the pelite-derived end-member,showing that the Pengshan muscovite-granite and biotite adamellite mainly originated from the partial melting of metapelites with high maturity.The transformation of the compressional and extensional tectonics in this region approximately 128 Ma obviously lags behind that in the mid-segment of the Jiangnan Uplift(135 Ma),but occurred earlier than the MLYDZ(126 Ma).The Pengshan ore field extends from the mid-segment of the Jiangnan Uplift to the MLYDZ.Although the tectonic stress field is constrained by the combination of the two secondary tectonic units,the time of tectonic system transformation is closer to the MLYDZ because the spatial orientation of the area is enclosed in the MLYDZ.Relevant geophysical and drilling data confirm the rationality of Pengshan-Ao'xia as a multi-center vertical zoning ore field,and show the scientificity of the prospecting idea of abutting joint between the north-west of Pengshan area and the south-east of Ao'xia area. 展开更多
关键词 zircon dating s-type granite Early Cretaceous syn-collisional DYNAMICS Pengshan Sn-polymetallic ore field
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Chronology and Genesis of S-type Granites in Hetai District, Guangdong Province: Constraints from LA-ICP-MS Zircon U-Pb Dating and Tourmaline Boron Isotope In-situ Analyses 被引量:1
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作者 WANG Lixing XU Deru +1 位作者 CHEN Genwen ZHU Yuhua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期96-97,共2页
1 Introduction Hetai district,which is a mountainous area,situated on Guangning and Zhaoqing city,west Guangdong Province.Hetai district is generally located on southwest of South China Caledonian fold belt,east margi... 1 Introduction Hetai district,which is a mountainous area,situated on Guangning and Zhaoqing city,west Guangdong Province.Hetai district is generally located on southwest of South China Caledonian fold belt,east margin of Yunkai post-Caledonian uplift.Multiple type granites are widely distributed in Hetai district,including Caledonian,Indosinian and Yanshanian granites.Based on different 展开更多
关键词 Pb Chronology and Genesis of s-type Granites in Hetai District Constraints from LA-ICP-MS Zircon U-Pb Dating and Tourmaline Boron Isotope In-situ Analyses Guangdong Province type
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Weighted composition operators from F(p,q,s) spaces to Bers-type spaces in the unit ball 被引量:2
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作者 LU Xiao-fen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期462-472,共11页
This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to ... This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal. 展开更多
关键词 F(p Q s) space Bers-type space weighted composition operator unit ball
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Activation of Sonic Hedgehog Signaling Pathway in S-type Neuroblastoma Cell Lines
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作者 周昱男 戴若连 +4 位作者 毛玲 夏远鹏 姚玉芳 杨雪 胡波 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第3期271-277,共7页
The effects of Sonic hedgehog(Shh) signaling pathway activation on S-type neuroblastoma(NB) cell lines and its role in NB tumorigenesis were investigated.Immunohistochemistry was used to detect the expression of Shh p... The effects of Sonic hedgehog(Shh) signaling pathway activation on S-type neuroblastoma(NB) cell lines and its role in NB tumorigenesis were investigated.Immunohistochemistry was used to detect the expression of Shh pathway components— Patched1(PTCH1) and Gli1 in 40 human primary NB samples.Western blotting and RT-PCR were used to examine the protein expression and mRNA levels of PTCH1 and Gli1 in three kinds of S-type NB cell lines(SK-N-AS,SK-N-SH and SHEP1),respectively.Exogenous Shh was administrated to activate Shh signaling pathway while cyclopamine was used as a selective antagonist of Shh pathway.S-type NB cell lines were treated with different concentrations of Shh or/and cyclopamine for different durations.Cell viability was measured by using MTT method.Apoptosis rate and cell cycle were assayed by flow cytometry.The xenograft experiments were used to evaluate the role of Shh pathway in tumor growth in immunodeficient mice.High-level expression of PTCH1 and Gli1 was detected in both NB samples and S-type NB cell lines.Cyclopamine decreased the survival rate of the three cell lines while Shh increased it,and the inhibition effects of cyclopamine could be partially reversed by shh pre-treatment.Cyclopamine induced the cell apoptosis and the cell cycle arrest in G0/G1 phase,while Shh induced the reverse effects and could partially prevent effects of cyclopamine.Cyclopamine could also inhibit the growth of NB in vivo.Our studies revealed that activation of the Shh pathway is important for survival and proliferation of S-type NB cells in vivo and in vitro through affecting cell apoptosis and cell cycle,suggesting a new therapeutic approach to NB. 展开更多
关键词 s-type neuroblastoma cell lines Sonic hedgehog signaling pathway CYCLOPAMINE
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挑战“双B”美洲豹新鲜出击——Jaguar New S-Type 3.0
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作者 孙祥隆 《轻型汽车技术》 2004年第6期77-80,共4页
在迈入21世纪之始,Jaguar以S-Type作为首次跨入主管级豪华房车市场区区的开路先锋,当时汇集最尖端工艺技术、融合独特设计创意的S-Type,一推出便深受全球车坛的瞩目,同时也为TAGUAR揭开世纪交替的序幕,为日后上市的X-Type.全新XJ... 在迈入21世纪之始,Jaguar以S-Type作为首次跨入主管级豪华房车市场区区的开路先锋,当时汇集最尖端工艺技术、融合独特设计创意的S-Type,一推出便深受全球车坛的瞩目,同时也为TAGUAR揭开世纪交替的序幕,为日后上市的X-Type.全新XJ系列奠下良好的基础。转眼间。 展开更多
关键词 JAGUAR NEW s-type轿车 车型设计 动力性能 操控性能
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捷豹S-Type
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作者 佟星 《汽车驾驶员》 2007年第8期38-39,共2页
你可以花60万元买到一款豪华轿车,但你未必就能因此收获到更多的魅力。一只充满灵性的飞豹划过长空,惊艳之中彰显绅士气质,这样的魅力,谁人可挡呢?
关键词 捷豹s-type 汽车 内饰 外观 技术参数
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2005款捷豹S-TYPE电子手刹故障
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作者 罗凯 《汽车维修技师》 2013年第1期87-88,共2页
车型:2005款捷豹S-TYPE. 行驶里程:137750km. 故障现象:仪表上制动系统报警灯点亮,有时电子手刹无法释放. 故障诊断:接车后,验证故障现象,确如客户所述.使用SDD诊断仪进入系统读取故障码,发现在相关事件里面并没有相关的故障码. 执行建... 车型:2005款捷豹S-TYPE. 行驶里程:137750km. 故障现象:仪表上制动系统报警灯点亮,有时电子手刹无法释放. 故障诊断:接车后,验证故障现象,确如客户所述.使用SDD诊断仪进入系统读取故障码,发现在相关事件里面并没有相关的故障码. 执行建议选项,建议诊断驻车执行机构.点击确定以后,听到电机转动的声音,车辆手刹也可以正常的运作.以为只是一起偶发故障,在经过几次测试后均没问题,将车交与客户使用. 展开更多
关键词 手刹 手制动器 s-type 捷豹 电子 轻子
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绅士变身记 JAGUAR S-TYPE & JAGUAR XF
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作者 张研 王一鸣 霍庆泽 《世界汽车》 2016年第5期58-69,共12页
"犹记得戴安娜王妃初入皇室时,她驾驶着一辆经典的绿色S-Type,这款贵族座驾身形圆润、极富美感,不仅与王妃高贵气质相得益彰,也诠释着捷豹早期所崇尚的复古主义经典造型。跨入21世纪,捷豹全球设计总监严凯伦先生以一款风尚魅力的X... "犹记得戴安娜王妃初入皇室时,她驾驶着一辆经典的绿色S-Type,这款贵族座驾身形圆润、极富美感,不仅与王妃高贵气质相得益彰,也诠释着捷豹早期所崇尚的复古主义经典造型。跨入21世纪,捷豹全球设计总监严凯伦先生以一款风尚魅力的XF向世界昭告捷豹全新时代的到来,为我们演绎了一出精妙绝伦的绅士变身记。" 展开更多
关键词 捷豹 复古主义 高贵气质 设计总监 座驾 凯伦 JAGUAR s-type JAGUAR XF 转向盘 戴安娜
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2003款美洲虎S-Type R轿车
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《世界汽车》 2002年第12期33-34,共2页
在推出美洲虎S-Type轿车3年之后,美洲虎发布了全新设计的2003款S-Type R轿车。新款美洲虎S-Type R轿车在外型上没有做太大的改动,但为了显示其卓越的性能,对其内在结构进行了较大的改进。除了与车身同色的网状散热器护罩外。
关键词 2003款美洲虎s-type R轿车 性能特点 设计 结构配置 技术装备
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移动的古朴——试驾捷豹S-Type 3.0
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作者 敬伟 《汽车时代》 2004年第11期34-37,共4页
一场热闹非凡的F1上海站赛事,让很多人领略了一级方程式赛车那V10发动机发出的刺耳狂嚣,记住了车神舒马赫那菲夷所思的冲出赛道、撞车、爆胎等意外,如此诸多的新闻及花絮中,一则捷豹车队将要退出F1赛事的新闻吸引了我的注意。
关键词 捷豹 s-type 3.0 一级方程式赛车 舒马赫 上海站 车神 驻车制动 前大灯 侧面碰撞 自动变
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A GENERALIZED GAUSS-TYPE QUADRATURE FORMULA AND ITS APPLICATIONS TO PSEUDOSPECTRAL METHOD
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作者 王立联 郭本瑜 王中庆 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2002年第2期179-196,共18页
A generalized Gauss-type quadrature formula is introduced, which assists in selection of collocation points in pseudospectral method for differential equations with two-point derivative boundary conditions. Some resul... A generalized Gauss-type quadrature formula is introduced, which assists in selection of collocation points in pseudospectral method for differential equations with two-point derivative boundary conditions. Some results on the related Jacobi interpolation are established. A pseudospectral scheme is proposed for the Kuramoto-Sivashisky equation. A skew symmetric decomposition is used for dealing with the nonlinear convection term. The stability and convergence of the proposed scheme are proved. The error estimates are obtained. Numerical results show the efficiency of this approach. 展开更多
关键词 GENERALIZED Gauss-type QUADRATURE formula PSEUDOSPECTRAL method K-S equa-tion.
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Bandgap Properties for the Folded S-Type Periodic Structure:Numerical Simulation and Experiment
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作者 Tongtong Huo Zhijing Wu Fengming Li 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2023年第5期624-632,共9页
The central wavelength of the first Bragg scattering bandgap is approximately twice that of the lattice.Therefore,a low-frequency Bragg scattering bandgap with a small structural dimension for phononic crystals is dif... The central wavelength of the first Bragg scattering bandgap is approximately twice that of the lattice.Therefore,a low-frequency Bragg scattering bandgap with a small structural dimension for phononic crystals is difficult to obtain.In this study,a folded S-type periodic structure is developed to reduce the dimension in the direction of vibration suppression by folding unit cells.According to the foregoing,an improved folded S-type periodic structure with different unit cell arrangements is designed to widen the bandgap frequency range.Energy band diagrams and frequency responses are calculated based on the Bloch theory and using the finite element method.Furthermore,a prototype of the improved folded S-type periodic structure is fabricated using a three-dimensional printing technique,and a vibration experiment is conducted.To verify the vibration reduction performance of the structure,numerical simulation and experimental results are compared.This type of folded periodic structure can effectively reduce dimensions to satisfy the dimension requirements pertaining to the direction of vibration suppression.Hence,the foregoing can aid in promoting the use of elastic bandgap structures in engineering. 展开更多
关键词 Folded s-type periodic structure Bandgap Vibration reduction Finite element method Vibration experiment
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S型异质结光催化剂的研究进展
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作者 刘敏 黄秀 张理元 《无机盐工业》 CAS CSCD 北大核心 2024年第7期18-27,共10页
光催化技术具有合成过程简便、反应条件易控制、充分利用太阳能且无二次污染等突出优势,在处理环境污染问题和缓解全球能源短缺等方面具有广阔的应用前景。然而,由于光生载流子低的转移和分离效率,实际的光化学转换效率提升受到了限制... 光催化技术具有合成过程简便、反应条件易控制、充分利用太阳能且无二次污染等突出优势,在处理环境污染问题和缓解全球能源短缺等方面具有广阔的应用前景。然而,由于光生载流子低的转移和分离效率,实际的光化学转换效率提升受到了限制。新兴的S型异质结光催化剂由于其在空间上实现了光生载流子的有效转移分离并展现出强的氧化还原能力,在太阳燃料制备和环境治理领域受到了广泛关注和研究。综述了异质结光催化剂的发展历程和S型异质结的基本原理及在各领域中的应用。最后,总结了S型异质结光催化剂的突出优势,并提出S型异质结光催化剂的发展前景和面临的挑战,为开发具备高效光催化活性的新型异质结光催化剂提供思路和参考。 展开更多
关键词 S型异质结 光催化 析氢 二氧化碳还原 降解
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滇东南薄竹山花岗岩年代学、地球化学特征及地质意义
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作者 黄建国 任涛 +2 位作者 刘红卫 罗光明 管申进 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2024年第3期621-635,共15页
滇东南薄竹山地区W-Sn-Pb-Zn多金属矿床与该区大型复式花岗岩体有密切的成因联系。为了探讨该花岗岩体的侵位时代、岩石成因及形成背景,对薄竹山花岗岩开展了岩石地球化学、锆石U-Pb定年及Hf同位素测试。结果表明,该花岗岩可划分为两期... 滇东南薄竹山地区W-Sn-Pb-Zn多金属矿床与该区大型复式花岗岩体有密切的成因联系。为了探讨该花岗岩体的侵位时代、岩石成因及形成背景,对薄竹山花岗岩开展了岩石地球化学、锆石U-Pb定年及Hf同位素测试。结果表明,该花岗岩可划分为两期,其中晚期花岗岩LA-ICP-MS锆石U-Pb年龄为(87.08±0.55)~(87.29±0.69)Ma。两期花岗岩均具高的SiO_(2)(63.37%~72.07%)、K_(2)O(4.96%~6.19%),贫Fe、Mg的特征,A/CNK值为1.03~2.42,轻重稀土元素分异明显(LREE/HREE=14.0~26.5),Eu明显负异常(δEu=0.38~0.62),富含大离子亲石元素Rb、Th、U及稀土元素La、Ce、Nd,亏损Ba、Ta、Nb、Sr、Y和Yb,ε_(Hf)(t)值为−9.31~−5.14,具有高钾钙碱性过铝质S型花岗岩的地球化学和同位素特征;Hf同位素二阶段模式年龄(t_(DM2))为1476~1737 Ma,说明岩浆可能来源于早中元古代下地壳部分熔融。综合研究认为,薄竹山花岗岩是白垩纪伸展背景下软流圈地幔上涌导致的早中元古代下地壳物质部分熔融所形成。 展开更多
关键词 锆石U-PB定年 地球化学 S型花岗岩 薄竹山 滇东南
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基于多类型语音信息分层融合的帕金森病检测模型
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作者 吴迪 季薇 +1 位作者 郑慧芬 李云 《模式识别与人工智能》 EI CSCD 北大核心 2024年第9期811-823,共13页
用于帕金森病检测的语音数据通常包括持续元音、重复音节及情景对话等类型.已有模型大多采用单一类型的语音数据作为输入,容易受到噪声干扰,鲁棒性无法保证.有效整合不同类型语音数据,提取至关重要的病理信息,是当前帕金森病检测任务面... 用于帕金森病检测的语音数据通常包括持续元音、重复音节及情景对话等类型.已有模型大多采用单一类型的语音数据作为输入,容易受到噪声干扰,鲁棒性无法保证.有效整合不同类型语音数据,提取至关重要的病理信息,是当前帕金森病检测任务面临的挑战之一.文中提出基于多类型信息分层融合的帕金森病检测模型,旨在提取全面的病理信息,实现较优的检测性能.首先,针对不同类型的帕金森病语音数据,分别进行多种声学特征的提取.然后,设计挖掘多类型声学特征深层信息的表示学习方案,提取调音和韵律信息,精准反映声学特征中潜在的病理信息.进而针对两类信息,设计解耦的表示学习空间,分别提取各自的私有特征,同时学习它们的共有表示.最后,设计跨类型的注意力分层融合模块,利用交叉注意力机制,以不同粒度交互的方式逐步融合共有表示和私有表示,提升帕金森病检测性能.在公开的意大利语帕金森病语音数据集和自采的汉语帕金森病语音数据集上的实验表明,文中方法性能提升明显. 展开更多
关键词 帕金森病 多类型语音 对比学习 分层融合
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粤北地区塘洞岩体地球化学特征及地质意义
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作者 龙自强 彭渤洋 刘斌 《铀矿地质》 CAS CSCD 2024年第3期459-469,共11页
塘洞岩体位于粤北地区长江铀矿集区北部,具有较好的铀成矿地质条件。文章通过对塘洞岩体岩相学、地球化学分析,初步探讨了塘洞岩体成因及其形成的构造环境。结果表明:塘洞岩体岩性为中粒二云母花岗岩,具有高硅(SiO_(2)=72.77%~73.83%)... 塘洞岩体位于粤北地区长江铀矿集区北部,具有较好的铀成矿地质条件。文章通过对塘洞岩体岩相学、地球化学分析,初步探讨了塘洞岩体成因及其形成的构造环境。结果表明:塘洞岩体岩性为中粒二云母花岗岩,具有高硅(SiO_(2)=72.77%~73.83%)、富铝(Al_(2)O_(3)=13.13%~13.82%)、富碱(K2O=5.00%~6.84%,Na_(2)O=1.55%~2.67%),且钾大于钠,贫铁、镁、钙、钛、磷,铝饱和指数(A/CNK=1.08~1.28)大部分大于1.1的特征,属高钾钙碱性弱过铝质-过铝质花岗岩;稀土元素总量较高,属轻稀土富集型(LREE/HREE=8.45~12.86),明显铕负异常(δEu=0.24~0.30);富集大离子亲石元素Rb、Th、U、K、Pb,而贫Nb、Ta、Ti、Zr等高场强元素。塘洞岩体CaO/Na_(2)O=0.16~0.58、Rb/Sr=5.01~8.19、Ra/Ba=0.90~1.94,指示其源区为砂质岩与泥质岩混合,属于S型花岗岩,主要为同碰撞后期在碰撞加厚向伸展减薄构造转换阶段的地壳物质经部分熔融形成的。 展开更多
关键词 S型花岗岩 地球化学 岩石成因 塘洞岩体 粤北地区
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桂东北苗儿山地区上小地加里东期花岗斑岩成因及其与铀成矿关系
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作者 王珂 吴昆明 +6 位作者 朱煜翔 欧阳平宁 黄宏业 范鹏飞 陈琪 谭双 谷勇 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第3期580-596,I0001,I0002,共19页
华南印支期花岗岩中广泛发育热液铀矿床,然而加里东期花岗岩体中的铀矿化却鲜有报道。近年来,在桂东北苗儿山地区上小地加里东期花岗岩体中已识别出多个铀矿体,它们在空间上与花岗斑岩脉存在密切联系。为了探究该花岗斑岩脉成因及其与... 华南印支期花岗岩中广泛发育热液铀矿床,然而加里东期花岗岩体中的铀矿化却鲜有报道。近年来,在桂东北苗儿山地区上小地加里东期花岗岩体中已识别出多个铀矿体,它们在空间上与花岗斑岩脉存在密切联系。为了探究该花岗斑岩脉成因及其与铀成矿关系,本文对其开展了详细的野外地质调查、岩相学、锆石U-Pb年代学及地球化学研究。花岗斑岩呈岩脉形式侵入苗儿山加里东期花岗岩基之中,两者关系截然。LA-ICP-MS锆石U-Pb定年获得花岗斑岩的年龄为422~426 Ma,与加里东期花岗岩体形成时限(~421 Ma)基本一致,属于加里东期岩浆活动晚期产物。该岩石高硅(SiO_(2)=70.85%~71.74%)、高钾(K_(2)O=4.71%~5.55%),属于过铝质‒强过铝质(A/CNK=1.00~1.15),微量元素相对富集U、Th、Rb等大离子亲石元素、亏损Nb、Ta、Zr、Hf等高场强元素,稀土元素总量(ΣREE=239×10^(−6)~288×10^(−6))低,具有明显的Eu负异常(δEu=0.22~0.28),与区域加里东期花岗岩的地化特征一致。综合分析,认为上小地花岗斑岩为一套S型花岗岩,形成于后碰撞构造背景下,由中、上地壳古元古代变质砂岩、泥质岩部分熔融产生的长英质岩浆经历一定程度的结晶分异形成。该花岗斑岩与区内的铀矿存在巨大的形成时差,仅为铀矿质的沉淀提供了有利构造条件。 展开更多
关键词 上小地花岗斑岩 地球化学 S型花岗岩 后碰撞 铀成矿作用
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