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FUNCTIONAL CHARACTERIZATION OF CADMIUM-RESPONSIVE GARLIC GENE ASMT2B: A NEW MEMBER OF METALLOTHIONEIN FAMILY

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Chinese Science Bulletin 2006年第4期51卷 409-416页

作者： zhang haiyan XUWenzhong DAI Wentao HE Zhenyan MA Mi Key Laboratory of Photosynthesis and Environmental Molecular Physi-ology Institute of Botany Chinese Academy of Sciences Beijing 100093China

A new gene of metallothionein (MT) family was cloned from garlic (Allium sativum) seed-lings using RACE method and designated AsMT2b. The full length of AsMT2b cDNA was 520 bp encod-ing 80 amino acids. The deduced amino acids of AsMT2b showed that AsMT2b contained the char-acteristic structure of type 2 MT proteins, but the number and arrangement of the cysteine residues in the N- and C-terminal domains was different from other type 2 MT proteins. Semi-quantitative reverse transcriptase-PCR showed that transcript levels of AsMT2b were enhanced only in response to higher concentrations or longer incubation time of Cd. Such an expression pattern of AsMT2b greatly differed from that of other type 2 MT genes. Yeast cells transformed with this gene had improved resistance to Cd. AsMT2b overexpressing Arabidopsis showed stronger Cd tolerance and higher Cd accumulation compared with wild-type plants. These results sug-gest that AsMT2b should be useful in phytoremedia-tion of Cd-polluted soil in the future.

关键词：大蒜金属硫因重金属污染转基因植物功能特征化镉基因克隆

Intrinsic defects in biomass-derived carbons facilitate electroreduction of CO2

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Nano Research 2020年第3期13卷 729-735页

作者： Mengjie Chen Shuai Wang haiyan zhang Ping zhang Ziqi Tian Min Lu Xiaoji Xie Ling Huang Wei Huang Key Laboratory of Flexible Electronics(KLOFE) Institute of Advanced Materials(IAM)Nanjing Tech UniversityNanjing211816China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo315201China Shaanxi Institute of Flexible Electronics Northwestern Polytechnical UniversityXi’an710072China

Developing efficient carbon-based metal-free electrocatalysts can bridge the gap between laboratory studies and practical applications of CO2 ***,along with the ambiguous understanding of the active sites in carbon-based electrocatalysts,carbon-based electrocatalysts with high selectivity and satisfactory stability for electroreduction of CO2 remain ***,using the nitrogen rich silk cocoon as a precursor,carbon-based electrocatalysts with intrinsic defects can be prepared for efficient and long-term electroreduction of CO2 by a simple two-step *** obtained electrocatalyst can catalyze CO2 reduction to CO with a Faradaic efficiency of^89%and maintain good selectivity for about 10 ***,our experimental studies suggest that in-plane defects are the main active sites on which the rate-determining step for CO2 reduction should be the direct electron transfer to CO2 but not the proton-coupled electron *** theoretical calculations consistently demonstrate that the intrinsic defects in carbon matrix,particularly the pentagon-containing defects,act as main active sites to accelerate the direct electron transfer for CO2 *** addition,our synthetic approach can convert egg white into efficient catalysts for CO2 *** findings,providing new insights into the biomass-derived catalysts,should pave the way for fabricating efficient and stable carbon-based electrocatalysts with catalytically active defects by using naturally abundant precursors.

关键词： carbon dioxide reduction carbon-based catalyst defect biomass

Brain cell apoptosis and enhancement of nervous excitability in pregnant rats with high plasma levels of homocysteine

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Neural Regeneration Research 2012年第28期7卷 2199-2205页

作者： Jun Wang Jing Ge Liu Yang haiyan zhang Xuli Li Dan Xue Department of Gynaecology and Obstetrics General Hospital of Shenyang Military Region Shenyang 110016 Liaoning Province China Department of Gynaecology and Obstetrics the 202 Hospital of Chinese PLA Shenyang 110003 Liaoning Province China Shenyang Women and Children Health Center Shenyang 110014 Liaoning Province China

Hyperhomocysteinemia is an important risk factor for preeclampsia-eclampsia. This study established a pregnant rat model of hyperhomocysteinemia, in which blood plasma homocysteine concentrations were twice or three times greater than that of normal pregnant rats. TUNEL revealed an increase in the number of apoptotic cells in the frontal cortex of pregnant rats with hyperhomocysteinemia. In addition, immunohistochemical staining detected activated nuclear factor-KB-positve cells in the frontal cortex. Reverse transcription-PCR detected that mRNA expression of the anti-apoptotic gene bcl-2 diminished in the frontal cortex. In situ hybridization and western blotting revealed that N-methyi-D- aspartate receptor 1 mRNA and protein expression was upregulated in the frontal cortex and hippocampus. These results indicate that hyperhomocysteinemia can induce brain cell apoptosis, increase nerve excitability, and promote the occurrence of preeclampsia in pregnant rats.

关键词： hyperhomocysteinemia homocysteine preeclampsia frontal cortex N-methyI-D-aspartate receptor nerve excitability cell apoptosis pregnancy brain neural regeneration

Spectral Index Distribution of Various Scale Components in Supernova Remnant Cassiopeia A

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Research in Astronomy and Astrophysics 2024年第5期24卷 211-217页

作者： Xianhuan Lei Hui Zhu Zongyao Yin haiyan zhang Wenwu Tian Xianchuan Yu Key Laboratory of Radio Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China School of Artiﬁcial Intelligence Beijing Normal UniversityBeijing 100875China

Cassiopeia A(Cas A) is a well-known candidate for studying cosmic-ray acceleration, in which compact features of various scales have attracted much attention. Based on observations by the Very Large Array of Cas A at 6 cm and 21 cm, we measure the spectral index distribution of various scale components using the observation of the 1998 epoch. We decompose its total density image into nine scale components, and map the temperature spectral index distribution of each component, which ranges from-2.48 ± 0.01 to-2.91 ± 0.05. We find that the spectral indices increase from the small scale to large scale components. A damped post-shock magnetic field model with a strength larger than ~200 μG and a damping length scale less than ~10% of the remnant radius can account for the spectral index variation naturally.

关键词： ISM supernova remnants-(ISM:)cosmic rays-radio continuum ISM

Mixed-Type Reverse Order Laws Associated to {1, 3, 4}-Inverse

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Journal of Mathematical Research with Applications 2019年第5期39卷 529-539页

作者： haiyan zhang Chunyuan DENG School of Mathematics and Statistics Shangqiu Normal University School of Mathematics Sciences South China Normal University

In this paper, we study the mixed-type reverse order laws to {1, 3, 4}-inverses for closed range operators A, B and AB. It is shown that B{1, 3, 4}A{1, 3, 4} ?(AB){1, 3} if and only if R(A*AB) ? R(B). For every A(134)∈ A{1, 3, 4}, it has(A(134)AB){1, 3, 4}A{1, 3, 4} =(AB){1, 3, 4} if and only if R(AA*AB) ? R(AB). As an application of our results, some new characterizations of the mixed-type reverse order laws associated to the Moore-Penrose inverse and the {1, 3, 4}-inverse are established.

关键词： {1,3,4}-inverse reverse order law generalized inverse block-operator matrix

Tree ring based drought variability in Northwest Tajikistan since 1895 AD

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Journal of Arid Land 2020年第3期12卷 413-422页

作者： YANG Meilin YU Yang zhang haiyan WANG Qian GAN Miao YU Ruide State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China School of Environment and Material Science Yantai UniversityYantai 264005China

Determining the mechanisms controlling the changes of wet and dry conditions will improve our understanding of climate change over the past hundred years,which is of great significance to the study of climate and environmental changes in the arid regions of Central *** trees are ecologically significant in the local environment,and therefore the tree ring analysis can provide a clear record of regional historical *** study analyzed the correlation between the tree ring width chronology of Juniperus turkestanica Komarov and the standardized precipitation evapotranspiration index(SPEI)in Northwest Tajikistan,based on 56 tree ring samples collected from Shahristan in the Pamir *** data including precipitation,temperature and the SPEI were downloaded from the Climate Research Unit(CRU)TS *** COFECHA program was used for cross-dating,and the ARSTAN program was used to remove the growth trend of the tree itself and the influence of non-climatic factors on the growth of the trees.A significant correlation was found between the radial growth of *** trees and the monthly mean SPEI of February–*** monthly mean SPEI sequence of February–April during the period of 1895–2016 was reconstructed,and the reconstruction equation explained 42.5%of the *** the past 122 a(1895–2016),the study area has experienced three wetter periods(precipitation above average):1901–1919,1945–1983 and 1995–2010,and four drier periods(precipitation below average):1895–1900,1920–1944,1984–1994 and 2011–*** spatial correlation analysis revealed that the monthly mean SPEI reconstruction sequence of February–April could be used to characterize the large-scale dry-wet variations in Northwest Tajikistan during the period of 1895–*** study could provide comparative data for validating the projections of climate models and scientific basis for managing water resources in Tajikistan in the context of climate change.

关键词： tree ring width chronology standardized precipitation evapotranspiration index(SPEI) drought Juniperus turkestanica Pamir region

Third Hankel Determinant for Ma-Minda Bi-univalent Functions

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Journal of Mathematical Research with Applications 2019年第4期39卷 361-377页

作者： haiyan zhang Huo TANG School of Mathematics and Computer Science Chifeng University

In this paper, we investigate the third Hankel determinant H3（1） for the class Hσμ（λ, φ）(λ≥ 1, μ≥ 1) of Ma-Minda bi-univalent functions in the open unit disk D = {z : |z| <1} and obtain the upper bound of ... 详细信息

关键词： analytic function Hankel determinant Ma-Minda bi-univalent function upper bound

Reduced graphene oxide wrapped 3D-ultrathin CoS2 nanoflakes as an absorbing material with enhanced microwave absorption

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Progress in Natural Science:Materials International 2022年第1期32卷 20-26页

作者： Danfeng zhang Chengjie Yan Yun Zheng Congai Han Yunfei Deng Jiale Yu Guoxun Zeng haiyan zhang School of Computer Science and Technology Guangdong University of Technology School of Material and Energy Guangdong University of Technology Sun Yat-sen University Cancer Center State Key Laboratory of Oncology

Novel 3D-ultrathin CoS2nanoflakes wrapped by reduced graphene oxide（CoS2/RGO） were successfully prepared via a facile method. The morphology and structure of the materials were characterized by X-ray diffraction,scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The microwave absorption properties of the CoS2/RGO composites were also investigated. The composites exhibited optimal microwave absorption properties at a CoS2/RGO loading of 20 wt.% in paraffin matrix, with a reflection loss（RL） value of-36.5 d B at 12.1 GHz and a thickness of 2.0 mm. Furthermore, CoS2/RGO composites have an excellent absorption bandwidth（reflection loss below-10 d B） of 6.5 GHz. The results indicate that the RGO-wrapped 3D-ultrathin CoS2nanoflakes have a broad microwave absorption bandwidth,strong absorption, and are the candidates for the application as the advanced microwave absorbers.

关键词： CoS 2 3D-ultrathin nanoflakes Graphene wrapped Microwave absorption

An Optimized Labeling Scheme for Reachability Queries

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Computers, Materials & Continua 2018年第5期55卷 267-283页

作者： Xian Tang Ziyang Chen haiyan zhang Xiang Liu Yunyu Shi Asad Shahzadi School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201600China Lixin University of Accounting and Finance Shanghai 201620China Yanshan University Qinhuangdao 066004China NCBAE Lahore 54660Pakistani

Answering reachability queries is one of the fundamental graph *** approaches either accelerate index construction by constructing an index that covers only partial reachability relationship,which may result in performing cost traversing operation when answering a query;or accelerate query answering by constructing an index covering the complete reachability relationship,which may be inefficient due to comparing the complete node *** propose a novel labeling scheme,which covers the complete reachability relationship,to accelerate reachability queries *** idea is to decompose the given directed acyclic graph(DAG)G into two subgraphs,G1 and *** G1,we propose to use topological labels consisting of two integers to answer all reachability *** G2,we construct 2-hop labels as existing methods do to answer queries that cannot be answered by topological *** benefits of our method lie in two *** one hand,our method does not need to perform the cost traversing operation when answering *** the other hand,our method can quickly answer most queries in constant time without comparing the whole node *** confirm the efficiency of our approaches by extensive experimental studies using 20 real datasets.

关键词： DAG computing detection reachability queries processing