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Influence exerted by bone-conta.ning ta.get body on thermoacoustic imaging with current injection

Chinese Physics B 2019年第4期28卷 230-241页

作者： Yan-Hong Li guo-Qiang Liu jia-Xiang Song Hui Xia Institute of Electrical Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

Thermoacoustic imaging with current injection(ta.-CI) is a novel imaging technology that couples with electromagnetic and acoustic research, which combines the advanta.es of high contrast of the electrical impedance tomography and the high spatial resolution of sonography, and therefore has the potential for early diagnosis. To verify the feasibility of ta.-CI for complex bone-conta.ning biological tissues, the principle of ta.-CI and the coupling characteristics of fluid and solid were analyzed. Meanwhile, thermoacoustic(ta. effects for fluid model and fluid–solid coupling model were analyzed by numerical simulations. Moreover, we conducted experiments on animal cartilage, hard bone and biological soft tissue phantom with low conductivity(0.5 S/m). By injecting a current into the phantom, the thermoacoustic signal was detected by the ultrasonic transducer with a center frequency of 1 MHz, thereby the B-scan image of the objects was obta.ned. The B-scan image of the cartilage experiment accurately reflects the distribution of cartilage and gel, and the hard bone has a certa.n attenuation effect on the acoustic signal. However, compared with the ultrasonic imaging, the thermoacoustic signal is only attenuated during the outward propagation. Even in this case, a clear image can still be obta.ned and the images can reflect the change of the conductivity of the gel. This study confirmed the feasibility of ta.-CI for the imaging of biological tissue under the presence of cartilage and the bone. The novel ta.-CI method provides further evidence that it can be used in the diagnosis of human diseases.

关键词： biomedical imaging thermo-acoustic imaging fluid–solid coupling low conductivity

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Oxidation behavior of multi-component ta.W-Al-Ti alloy at 1173 K

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Rare Meta.s 2021年第7期40卷 1940-1948页

作者： jia-Xin Li Yu-Hong Chen Zhang-Jun Bai Bao-Jun Zhao Liang jia.g Lan-Er Wu School of Materials Science and Engineering North Minzu UniversityYinchuan 750021China CNMC Ningxia Orient group Co.Ltd Shizuishan 753000China School of Chemical Engineering The University of QueenslandBrisbaneQLD 4072Australia

ta.W alloys have unique properties but their applications at high temperatures are restricted due to their poor oxidation *** addition of Al and Ti decreases the oxidation rate of the alloy,as Al-conta.ned protective oxide layer could be *** this study,ternary and quaternary ta.W alloys conta.ning Al and Ti were prepared by hot press *** microstructures and oxidation behaviors of the alloys were studied at1173 *** results show that the oxidation kinetics of all alloys follows a parabolic law at short oxidation *** cyclic oxidation,the kinetics of quaternary alloys still obeys the parabolic law but that of ternary alloy has been changed into linear law kinetics after 8-h *** ternary alloy,an outer layer with dense and continuous alumina was formed during the initial sta.e,and phase transformation caused the oxides to peel *** comparison,the quaternary alloys depicted continuously solid solution of the oxides ***,Al and Ti played key roles in oxidation degree and affected the oxidation kinetics of ternary and quaternary alloys.

关键词： Oxidation behavior ta.W-based alloy Aluminum Tita.ium

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Effect of ta.on solidification characteristics and mechanical properties of DZ411 Ni-based superalloy

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中国铸造:英文版 2023年第5期20卷 376-386页

作者： Peng Peng Zi-jie Liu Yuan-li Xu Xu-dong Zhang Zhi-kun Ma jia-ta. Wang School of Materials and Energy Lanzhou UniversityLanzhou 730000China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi'an 710072China School of Physics and Electronic Information Qinghai Normal UniversityXining 810008QinghaiChina

The effects of ta.content(2.72wt.%,3.10wt.%and 4.00wt.%)on the solidification characteristics and mechanical properties of directionally solidified DZ411 Ni-based superalloys were *** is found that the content of Mo decreases with the increase of ta.in liquid phase after directional solidification,indicating the addition of ta.can reduce the element segregation in *** primary and secondary dendrite arm spacings(PDAS and SDAS)of the DZ411 alloy increase with the addition of ta.which are consistent with the models by Hunt and *** increase of PDAS and SDAS can provide enough space for the growth of tertiary dendrite arms,which hinders the growth of unfavorably oriented primary *** a result,the addition of ta.facilita.es the growth of favorably oriented *** MC carbides andγ-γ'eutectics are formed in the interdendritic regions,which is attributed to the segregation of ta.in the liquid ***,the degree of supersaturation of W,Mo inγmatrix increases with the increase of ta.thus,the addition of ta.promotes the formation of TCP *** addition of ta.also increases the microhardness in both the primary dendrite and interdendritic regions of the alloy,and the microhardness of the primary dendrite is closer to that in interdendritic regions with the increase of ta.

关键词： DZ411 superalloy directional solidification ta dendrite arm spacing microhardness

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基于改进贝叶斯网络的高维数据本地差分隐私方法

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信息网络安全 2023年第2期23卷 19-25页

作者：赵佳高塔张建成北京交通大学智能交通数据安全与隐私保护北京市重点实验室北京100044 北京交通大学计算机与信息技术学院北京100044 山东省计算中心济南250014 山东正中信息技术股份有限公司济南250014

文章提出一种基于改进贝叶斯网络的高维数据本地差分隐私方法,首先通过数据源差分隐私保护算法对用户端数据集进行扰动,生成扰动数据集,保护本地原始数据集隐私;然后通过改进的贝叶斯网络将高维数据集降维为多个低维属性集合;最后合成... 详细信息

文章提出一种基于改进贝叶斯网络的高维数据本地差分隐私方法,首先通过数据源差分隐私保护算法对用户端数据集进行扰动,生成扰动数据集,保护本地原始数据集隐私;然后通过改进的贝叶斯网络将高维数据集降维为多个低维属性集合;最后合成新数据集,使用人工蜂群算法对贝叶斯网络结构进一步改进。实验结果表明,该方法在数据实用性方面具有优势,且得到的贝叶斯网络收敛性更好。

关键词：本地差分隐私贝叶斯网络人工蜂群算法高维数据

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Impact of human ACAT1 on the dynamic free cholesterol in plasma membrane of neural cell line SK-N-SH

Impact of human ACAT1 on the dynamic free cholesterol in pla...

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脂质组学与脂蛋白的新功能——第十二届全国脂质与脂蛋白学术会议

作者： Ming Zhu Xiao-Nan Zhao jia Chen jia-jia Xu guang-Jing Hu Dong-Qing guo Qin Li Xiao-Wei Zhang Catherine C.Y.Chang Bao-Liang Song ta.Yuan Chang Ying Xiong Bo-Liang Li Sta.e Key Laboratory of Molecular Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of Sciences Department of Biochemistry Dartmouth Medical School

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Impact of human ACAT1 on the dynamic free cholesterol in plasma membrane of neural cell line SK-N-SH

Impact of human ACAT1 on the dynamic free cholesterol in pla...

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中国生物化学与分子生物学会第十一次会员代表大会暨2014年全国学术会议

作者： Ming Zhu Xiao-Nan Zhao jia Chen jia-jia Xu guang-Jing Hu Dong-Qing guo Qin Li Xiao-Wei Zhang Catherine C.Y.Chang Bao-Liang Song ta.Yuan Chang Ying Xiong Bo-Liang Li Sta.e Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Department of Biochemistry Dartmouth Medical School Hanover NH 03756 USA

Acyl-CoA:cholesterol acyltransferase(ACAT) is an intracellular exclusive enzyme which utilizes long-chain fatty acyl-CoA and free cholesterol as substrates to form cholesteryl esters. It is a key enzyme involved in mainta.ning cellular cholesterol homeosta.is, and plays importa.t roles in some serious human diseases including atherosclerosis, Alzheimer’s disease(AD) as well as cancer. In mammals, two ACAT genes encoding ACAT1 and ACAT2 have been identified. In this work, we report the impact of human ACAT1 on the dynamic free cholesterol in plasma membrane(PM-FC) of neural cell line SK-N-SH. First, the Filipin sta.ning and PM-FC determining assays indicate that the increase of the PM-FC content of neural cell line SK-N-SH is in dose and time dependent manners by the ACAT1 inhibition, while the western blot analyses display that the α-processing of amyloid precursor protein(APP) mainly on the plasma membrane can be inversely decreased. More importa.tly, we have observed that the decreased α-processing of APP by the ACAT1 inhibition can be conversely enhanced when depleting the increased PM-FC directly by methyl-β-cyclodextrin, meaning that the ACAT1 inhibition can impact the dynamic PM-FC which leads to the change of APP α-processing on the plasma membrane of neural cell line SK-NSH. Then, under the different levels of cellular cholesterols by inhibiting the absorption, efflux, synthesis of cholesterolsand/or increasing cholesterols by adding LDL or mevalonate in culture media, the results show that the ACAT1 inhibition can evidently impact the dynamic PM-FC. Finally, further evidences confirm that the α-processing of APP affected by the dynamic PM-FC through the ACAT1 activity change can be mimicked by the RNAi knockdown and overexpression of ACAT1 in neural cell line SK-N-SH. These data.suggest that ACAT1 impacting the dynamic PM-FC may play importa.t role in neural cells.

关键词： ACAT1 Dynamic free cholesterol Plasma membrane Alpha-processing of APP Neural cell line

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ta.RR1, a cytokinin response regulator gene in Triticum aestivum, is essential in plant N sta.vation tolerance via regulating the N acquisition and N assimilation

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Journal of Integrative Agriculture 2019年第12期18卷 2691-2702页

作者： YANg Meng-ya CHEN jia-qi TIAN He-yang NI Chen-yang XIAO Kai College of Agronomy Hebei Agricultural University/Key Laboratory of Crop Growth Regulation of Hebei Province

Plant N sta.vation response is closely associated with the N signaling components that involve transduction of the low-N cues. In this study, we functionally characterized ta.ARR1, a cytokinin(CK) response regulator gene in Triticum aestivum, in mediating the N sta.vation adapta.ion in plants. ta.ARR1 harbors two conserved domains specified by plant ARR family members;subcellular localization analysis indicated its ta.get onto nucleus after endoplasmic reticulum assortment. ta.ARR1 displayed modified expression upon the N sta.vation stressor, showing upregulated expression in roots and leaves over a 27-h N sta.vation treatment and whose induced transcripts were gradually recovered along with progression of the N recovery treatment. The tobacco lines overexpressing ta.ARR1 displayed improved low-N stress tolerance, displaying enlarged phenotype, increased biomass and N accumulation, and enhanced gluta.ine syntheta.e(gS) activities compared with wild type(WT) following the N sta.vation treatment. Expression analysis on genes encoding the nitrate transporter(NRT) and gS proteins in Nicotiana ta.acum revealed that Nt NRT2.2 and Nt gS3 are upregulated in expression in the N-deprived transgenic lines, whose expression patterns were contrasted to other above family genes that were unaltered on transcripts between the transgenic lines and WT. Transgene analysis validated the function of Nt NRT2.2 and Nt gS3 in regulating N accumulation, gS activity, growth traits, and N use efficiency in plants. These results suggested the internal connection between the ta.ARR1-mediated N sta.vation tolerance and the modified transcription of distinct N acquisitionand assimilation-associated genes. Our investigation together indicates that ta.ARR1 is essential in plant N sta.vation adapta.ion due to the gene function in transcriptionally regulating distinct NRT and gS genes that affect plant N upta.e and assimilation under the N sta.vation condition.

关键词： wheat(Triticum aestivum L.) cytokinin response regulator gene expression N sta.vation functional characterization

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西藏南木林地区达那古火山机构中花岗岩大地构造意义

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岩石矿物学杂志 2024年第4期43卷 803-820页

作者：韩飞宋元宝李峥黄永高代克刚张伟李应栩贾小川杨学俊四川省综合地质调查研究所稀有稀土战略资源评价与利用四川省重点实验室四川成都610081 西藏地质矿产勘查开发局第五地质大队西藏拉萨850000 中国地质调查局成都地质调查中心四川成都610081

新发现的西藏南木林地区达那古火山机构为探讨陆相火山机构岩相组成及其大地构造意义提供了窗口。本项研究对达那古火山机构开展了地质剖面测量、岩相学研究,并对期后侵入的斑状二长花岗岩进行了锆石U-Pb年代学和全岩地球化学分析。结... 详细信息

新发现的西藏南木林地区达那古火山机构为探讨陆相火山机构岩相组成及其大地构造意义提供了窗口。本项研究对达那古火山机构开展了地质剖面测量、岩相学研究,并对期后侵入的斑状二长花岗岩进行了锆石U-Pb年代学和全岩地球化学分析。结果表明,斑状二长花岗岩锆石U-Pb年龄为54.0±1.4 Ma,具有高硅(SiO_(2)=71.03%~75.88%)、高钾低钠(K_(2)O/Na_(2)O=1.45~1.79)、富碱(ALK=8.97%~9.67%)、低钛(TiO_(2)=0.17%~0.37%)等特征,铝饱和指数(A/CNK)介于0.95~1.00之间,里特曼指数(σ)介于2.45~3.38之间,属于准铝质、钙碱性岩石系列;轻稀土元素富集而重稀土元素相对亏损(LREE/HREE=7.60~9.78),且分异特征明显,(La/Sm)_(N)=2.85~4.21;Rb、Th、U等大离子亲石元素(LILE)和不相容元素相对富集,Nb、ta.P、Ti等高场强元素(HFSE)相对亏损,表现出具有典型的俯冲带弧型或者壳源岩浆岩的地球化学属性。综合上述地质信息表明,达那古火山机构形成于54 Ma之前,斑状二长花岗岩形成于印度-欧亚大陆碰撞期的活动大陆边缘构造背景,在幔源岩浆底侵作用下,中下地壳发生熔融,之后岩浆分异上升侵位于火山通道结晶而成。

关键词：达那古火山机构二长花岗岩地球化学构造背景西藏

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γ Radiative Decays to Light Quark Jets and Color Octet Mechanism

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Communications in Theoretical Physics 2006年第12期 1017-1022页

作者： gAO Ying-jia,~1 ZHANg Yu-Jie,~1 and CHAO Kuang-ta.(1,2) 1 Department of Physics, Peking University, Beijing 100871, China 2 China Center of Advanced Science and Technology (World Laboratory), Belling 100080, China

We study radiative decays of T to light quark jets in nonrelativistic QCD by ta.ing both the color singlet and color octet b5 operators into consideration. The cut for quark jet energy and cut for the angle between two quark jets are introduced. The sensitivity to the soft and collincar singularities in the loop integrals are greatly reduced by these cuts. With the jet energy cut of about 1 geV, and the jet angle cut of about 36°, the branching ratio for γ→γqqis found to be 8.2×10;from color singlet contributions. The color octet contributions could be much larger than that of color singlet, depending on the estimate of the color octet matrix elements. This process may provide a new test for the color octet mechanism in nonrelativistic QCD.

关键词： radiative decay jet color octet

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Visible-light-induced photocata.ytic CO_(2)reduction over zirconium meta. organic frameworks modified with different functional groups

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Journal of Environmenta. Sciences 2023年第10期132卷 22-30页

作者： Yuexian Du guang’an Jie Huilin jia jiahui Liu Jieyu Wu Yanghe Fu Fumin Zhang Weidong Zhu Maohong Fan Key Laboratory of the Ministry of Education for Advanced Cata.ysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China Zhejia.g Engineering Laboratory for green Syntheses and Applications of Fluorine-Conta.ning Specialty Chemicals Institute of Advanced Fluorine-Containing MaterialsZhejiang Normal UniversityJinhua 321004China Department of Chemical and Petroleum Engineering University of WyomingLaramieWY 82071USA

The reduction of CO_(2)into high value-added chemicals and fuels by a photocata.ytic technology can relieve energy shorta.es and the environmenta. problems caused by greenhouse *** the current work,an amino-functionalized zirconium meta. organic framework(Zr-MOF)was covalently modified with different functional groups via the condensation of Zr-MOF with 2-pyridinecarboxaldehyde(PA),salicylaldehyde(SA),benzaldehyde(BA),and trifluoroacetic acid(ta.,named Zr-MOF-X(X=PA,SA,BA,and ta.,respectively,through the post-synthesis *** with Zr-MOF and Zr-MOF-ta.the introduction of PA,SA,or BA into the framework of Zr-MOF can not only enhance the visible-light harvesting and CO_(2)capture,but also accelerate the photogenerated charge separation and transfer,thereby improving the photocata.ytic ability of Zr-MOF for CO_(2)*** results indicate that the modification of Zr-MOF with electron-donating groups can promote the photocata.ytic CO_(2)***,the current work provides an instructive approach to improve the photocata.ytic efficiency of CO_(2)reduction through the covalent modification of MOFs.

关键词： Photocata.ysis CO_(2)reduction Meta. organic frameworks Post-synthesis modification Electric effect

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