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小肝癌的MRI特征及诊断价值分析

中国CT和MRI杂志 2024年第8期22卷 74-76页

作者：李佳冯硕马继征中国中医科学院广安门医院南区放射科北京102618 中国中医科学院广安门医院南区循证医学中心北京102618 中国中医科学院广安门医院消化科北京100053

目的探讨小肝癌(SHCC)的增强磁共振成像(MRI)特征并分析其诊断价值。方法选取2018年7月~2023年5月在本院收治的疑似SHCC患者63例作为研究对象,所有患者均行增强MRI与MRI平扫检查,以手术病理结果或病理活检为“金标准”,采用Kappa一致性... 详细信息

目的探讨小肝癌(SHCC)的增强磁共振成像(MRI)特征并分析其诊断价值。方法选取2018年7月~2023年5月在本院收治的疑似SHCC患者63例作为研究对象,所有患者均行增强MRI与MRI平扫检查,以手术病理结果或病理活检为“金标准”,采用Kappa一致性检验,比较两种检查方式对SHCC的诊断价值,采用单因素和多因素Logistic回归分析确定SHCC的因素。结果63例疑似SHCC患者中共46例(73.02%)SHCC阳性,17例阴性。MRI平扫的确诊率78.26%(36/46)低于增强MRI确诊率93.48%(43/46)(P<0.05)。MRI平扫时T1WI序列以低信号居多,T2WI序列以高信号和略高信号为主;增强MRI扫描时,动脉期明显强化,门静脉期和延迟期强化下降,信号降低。MRI平扫诊断SHCC的灵敏度、特异度、准确率、阳性预测值、阴性预测值和Kappa系数值分别为78.26%、82.35%、79.37%、92.31%、58.33%和0.536,增强MRI诊断SHCC的灵敏度、特异度、准确率、阳性预测值、阴性预测值和Kappa系数值分别为93.48%、94.11%、93.65%、97.73%、84.21%和0.845,其中增强MRI诊断的灵敏度和准确率均高于MRI平扫(P均<0.05)。Logistic回归分析,结果显示MRI平扫T1WI序列低信号、T2WI序列高信号或略高信号、MRI增强扫描动脉期明显强化、门静脉期信号降低均为诊断SHCC阳性的独立危险因素(P<0.05)。结论较于MRI平扫检查,增强MRI检查对SHCC的诊断价值更高,具良好的应用价值。

关键词：增强磁共振成像磁共振成像平扫小肝癌诊断特征

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Multiuser beamforming based on max SINR for downlink spatial multiplexing MIMO

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 28-33页

作者： ma Peng-fei zheng Kan WANG Wen-bo Wireless Signal Processing and Network Laboratory Beijing University ofPosts and Telecommunications Beijing 100876 China

In this article, a method based on max signal interference noise ratio（SINR） criterion is proposed, to mitigate the interuser interference for downlink multiuser spatial multiplexing multi-input multi-output（MIMO） systems. Unlike the zero forcing （ZF） scheme in which the SNR is decreased when the interference is eliminated completely, max SINR method makes a compromise between noise and interuser interference. When the number of substreams is larger than the difference between the number of base station antennas and the sum of interference mobile station antennas, the ZF is infeasible An existing coordinated TX-RX block diagonalization（COOR BD） method uses preprocessing at the receiver to cancel the interuser interference. However, it cannot obtain more receive diversity gain because of the preprocessing. Analysis and simulation show that the max SINR scheme has better performance than the ZF method. Moreover, when the ZF is infeasible, the max SINR scheme can obtain more receive diversity gain than COOR BD in the two-user case.

关键词： array signal processing beamforming MIMO systems spatial multiplexing

Key techniques for 5G wireless communications:network architecture, physical layer,and maC layer perspectives

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Science China(Information Sciences) 2015年第4期58卷 5-24页

作者： ma zheng ZHANG zhengQuan DING ZhiGuo FAN PingZhi LI HengChao Provincial Key Lab of Information Coding and Transmission Southwest Jiaotong University Department of Communication Systems Lancaster University

The fourth generation(4G) mobile communication systems are offering service worldwide *** 4G systems could be loaded with much more services and data than previous systems, there is still a dramatic gap between the people’s practical requirements and what can be offered by the 4G ***, the research and development for the fifth generation(5G) systems have already been started. This article presents an overview of potential network architecture and highlights several promising techniques which could be employed in the future 5G systems. These techniques include non-orthogonal multiple access(NOma),massive multiple input and multiple output(MIMO), cooperative communications and network coding, full duplex(FD), device-to-device(D2D) communications, millimeter wave communications, automated network organization, cognitive radio(CR), and green communications. The state-of-art and implementation issue of these techniques are also addressed.

关键词： 5G software defined network non-orthogonal multiple access massive MIMO full duplex deviceto-device communications millimeter wa

Ionic liquid/tetraglyme hybrid Mg[TFSI]_2 electrolytes for rechargeable Mg batteries

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Green Energy & Environment 2019年第2期4卷 146-153页

作者： zheng ma maria Forsyth Douglas R.macFarlane Mega Kar School of Chemistry Faculty of Science Monash University ARC Centre of Excellence for Electromaterials Science IFM – Institute for Frontier Materials Deakin University

The electrochemical reversibility of Mg in hybrid electrolytes based on mixtures of ionic liquid and glyme based organic solvents was investigated for applications in rechargeable magnesium batteries(RMBs). The electrolytes demonstrate reversible reduction and oxidation of Mg only after being pre-treated with the dehydrating agent, magnesium borohydride, Mg[BH_4]_2, highlighting the importance of removing water in Mg based electrolytes. The addition magnesium di[bis(trifluoromethanesulfonyl)imide](Mg[TFSI]_2)(0.3 M) to N-butyl-n-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide [C4 mpyr][TFSI]/tetraglyme at a mole ratio of 1:2 showed stable CV cycling over almost 300 cycles while scanning electron microscopy(SEM) and X-ray diffraction(XRD) confirmed Mg deposition, showing non-dendritic morphology and a well-aligned growth. Further thermogravimetric analysis(TGA) demonstrated a mass retention of 79% at 250℃ for this electrolyte suggesting that the presence of the ionic liquid increases thermal stability substantially making these hybrid electrolytes compatible for RMBs.

关键词： Mg[TFSI]2 Ionic liquids Tetraglyme Rechargeable Mg battery Mg[BH4]2 dehydrate reagent

吉马酮通过FOXO3-FOXM1轴调控甲状腺癌BCPAP细胞的增殖、迁移和化疗耐药

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中国肿瘤生物治疗杂志 2024年第9期31卷 871-877页

作者：王洪涛马正单四新朱坤良苑留云河北以岭医院西药房河北石家庄050011 沧州市中心医院药学部河北沧州061000 沧州市中心医院急诊科河北沧州061000

目的:探究吉马酮通过叉头盒蛋白O3(FOXO3)-FOX亚类M1转录因子(FOXM1)信号通路调控人甲状腺癌细胞BCPAP和多柔比星(DOX)耐药BCPAP细胞(BCPAP/DOX)的增殖、迁移和化疗耐药。方法:常规培养BCPAP细胞,用BCPAP细胞构建BCPAP/DOX细胞,用MTT法... 详细信息

目的:探究吉马酮通过叉头盒蛋白O3(FOXO3)-FOX亚类M1转录因子(FOXM1)信号通路调控人甲状腺癌细胞BCPAP和多柔比星(DOX)耐药BCPAP细胞(BCPAP/DOX)的增殖、迁移和化疗耐药。方法:常规培养BCPAP细胞,用BCPAP细胞构建BCPAP/DOX细胞,用MTT法检测不同浓度吉马酮对BCPAP和BCPAP/DOX细胞增殖的影响。将BCPAP和BCPAP/DOX细胞分为Ctrl组(空白对照)、sh-NC组(转染sh-NC质粒)、低浓度吉马酮组(0.10 mmol/L)、高浓度吉马酮组(0.15 mmol/L)、高浓度吉马酮(0.15 mmol/L)+sh-FOXO3组(转染sh-FOXO3质粒),用转染试剂将sh-NC质粒和sh-FOXO3质粒转至相应的BCPAP和BCPAP/DOX细胞中。用CCK-8法、划痕愈合实验和WB法分别检测各组细胞的增殖、迁移能力,以及FOXO3、FOXM1、BAX、MMP-9和多药耐药-1(MDR-1)蛋白的表达。结果:在BCPAP和BCPAP/DOX细胞中成功地敲减了FOXO3的表达,低浓度和高浓度吉马酮均可显著抑制BCPAP和BCPAP/DOX细胞的增殖、迁移能力,降低细胞中FOMX1、MMP-9或MDR-1(BCPAP/DOX细胞)蛋白的表达,提升FOXO3和BAX蛋白的表达(均P<0.05),与低浓度比较,高浓度吉马酮的作用更为显著(均P<0.05),敲减FOXO3后可部分逆转吉马酮对这两种细胞的作用(均P<0.05)。结论:吉马酮可能通过FOXO3/FOXM1信号通路调控BCPAP和BCPAP/DOX细胞的增殖和迁移能力,降低BCPAP/DOX细胞化疗耐药性。

关键词：吉马酮叉头盒蛋白O3 叉头盒亚类M1转录因子甲状腺癌增殖迁移化疗耐药

Gold Nanoclusters Templated by Poly-cytosine DNA as Fluorescent Probes for Selective and Sensitive Detection of Thiocyanate

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Chemical Research in Chinese Universities 2019年第5期35卷 788-791页

作者： MO Lixin ZHAO Hengxin ma zheng YU Wenxiao Huihua College Hebei Normal UniversityShijiazhuang 050091P.R.China Center for Evaluation and Facility Developnent Hebei University of Economics and BusinessShijiazhuang 050061P.R.China

Gold nanoclusters(AuNCs) were prepared in the presence of the nucleobases of poly-cytosine DNAs in this paper. We have demonstrated tliat the fluorescence of the AuNCs is quenched by thiocyanate(SCN^-) through the interaction between SCN^- and gold atoms. AuNCs can receive energy from nucleobases to boost their emission intensity, while in the presence of SCN^-, they coordinate with Au atoms and influence the energy transfer between the nucleobases and AuNCs, leading to the fluorescence quenching. The decreased fluorescence intensity was in proportion to the concentration of SCN^- in the range of 8.0×10^-7-1.5×10^-5 mol/L with a limit of detection of 4.2×10^-7 mol/L(3σ). We further validated the practice of this probe througli the detection of SCbT in natural water samples.

关键词： Fluorescence Thiocyanate Gold nanocluster

Microstructure,mechanical and corrosion properties of Mg-Zn-Nd alloy with different accumulative area reduction after room-temperature drawing

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Rare Metals 2021年第4期40卷 897-907页

作者： Ming Gao zheng ma Iniobong PEtim Li-Li Tan Ke Yang School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

Good mechanical properties and corrosion resistance are the key factors for the application of biodegradable magnesium alloy wires as new medical implant *** study is aimed at investigating the influence of micros true tural evolution on mechanical and corrosion properties of Mg-2 Zn-0.5 Nd alloy(ZN20) during room-temperature *** decreases in the crosssectional area of ZN20 alloy during drawing refined the grains from 10 to 5 μm under the influence of cold deformation,the basal texture was rotated around radius direction,the basal texture became dominant,and the texture transformed from drawing direction(DD)// to a point between and parallel to *** ultimate tensile strength of the wire was increased by 44.7% compared with that of the extruded alloy due to grain boundary strengthening,hard orientation and work hardening during drawing process,while the elongation was decreased by 85% under the influence of work *** corrosion resistance of the alloy was improved after drawing due to grain refinement,while it was sensitive to prismatic texture.

关键词： magnesium Drawing Texture Corrosion property Mechanical property

Doubly Periodic Propagating Wave Patterns of （2＋1）-Dimensional maccari System

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Communications in Theoretical Physics 2007年第3期47卷 397-402页

作者： HUANG Wen-Hua LIU Yu-Lu ma zheng-Yi College of Science Zhejiang Huzhou University Huzhou 313000 China Shanghai Institute of Applied mathematics and Mechanics Shanghai University Shanghai 200072 China College of Science Zhejiang Lishui University Lishui 323000 China

Using the variable separation approach, we obtain a general exact solution with arbitrary variable separation functions for the （2＋ 1）-dimensional maccari system. By introducing Jacobi elliptic functions dn and nd in the seed solution, two types of doubly periodic propagating wave patterns are derived. We invest/gate the wave patterns evolution along with the modulus k increasing, many important and interesting properties are revealed.

关键词： maccari system variable separation method Jacobi elliptic function periodic wave

Program Error Mitigation in MLC NAND Flash Memory with Soft Decision Decoders

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China Communications 2021年第4期18卷 76-87页

作者： Zequn Fang zheng ma Xiaohu Tang Yue Xiao Youhua Tang School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610031China National Engineering Laboratory for integrated traffic data application technology Southwest Jiaotong UniversityChengdu 610031China

Benefiting from strong decoding capabilities,soft-decision decoding has been used to replace hard-decision decoding in various communication systems,and NAND flash memory systems are no ***,soft-decision decoding relies heavily on accurate soft *** to the incremental step pulse programming(ISPP),program errors(PEs)in multi-level cell(MLC)NAND flash memory have different characteristics compared to other types of errors,which is very difficult to obtain such accurate soft ***,the characteristics of the log-likelihood ratio(LLR)of PEs are investigated first in this ***,a PE-aware statistical method is proposed to determine the usage of PE mitigation *** order to reduce the PE estimating workload of the controller,an adaptive blind clipping(ABC)scheme is proposed subsequently to approximate the PEs contaminated LLR with different decoding ***,simulation results demonstrate that(1)the proposed PE-aware statistical method is effective in practice,and(2)ABC scheme is able to provide satisfactory bit error rate(BER)and frame error rate(FER)performance in a penalty of negligible increasing of decoding latency.

关键词： program errors soft-decision decoder NAND flash memory clipping approximation