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Rare Metals 2016年第2期35卷 177-183页

作者： yu-Hao Zhai yu-juan zhang Yi Peng Sheng-Mao zhang Ping-yu zhang Xiao-Min zhang Key Laboratory of Ministry of Education for Special Functional Materials Henan University College of Materials and Mineral Resources Xi’an University of Architecture and Technology

nc-Ti C/a-C：H nanocomposite films were prepared by filtered cathodic arc technique. The influence of C_2H_2/Ar flow ratio on the composition, structure, and mechanical properties of films was investigated by X-ray photoelectron spectroscopy（XPS）, X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）,Raman spectroscopy, nanoindentation, and ball-on-disc tribometry. The films show a nanocomposite structure in which Ti C crystallites are embedded in the amorphous matrix of a-C：H phase. C content in films increases with the flow ratio of C_2H_2/Ar, simultaneously, the crystallite size of TiC decreases. Contrary to the nc-Ti C/a-C：H films deposited by magnetron sputtering in which the sp3 C content increases with C_2H_2 flow rate, the increase of C_2H_2 flow rate leads to the increase of sp2 C content in films deposited by filtered cathodic arc technique. The nc-Ti C/a-C：H films deposited by cathodic arc technique have a pronounced hardness maximum of 30 GPa under the C_2H_2/Ar flow ratio of 12. Tribological performance of films is controlled by the sp2 content in films. Higher sp2 content promotes the formation of graphite-like transfer layer during sliding,and results in lower wear rate and friction coefficient.

关键词： Nanocomposite films Tribological performance Hardness

Damping-like effects in Heisenberg spin chain caused by the site-dependent bilinear interaction

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Communications in Theoretical Physics 2021年第1期73卷 45-53页

作者： yu-juan zhang Dun Zhao Zai-Dong Li School of Mathematics and Statistics Xidian UniversityXi’an 710126China School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000China Department of Applied Physics Hebei University of TechnologyTianjin 300401China

We investigate a continuous Heisenberg spin chain equation which models the local magnetization in ferromagnet with time-and site-dependent inhomogeneous bilinear interaction and timedependent spin-transfer *** establishing the gauge equivalence between the spin chain equation and an integrable generalized nonlinear Schrödinger equation,we present explicitly a novel nonautonomous magnetic soliton solution for the spin chain *** results display how the dynamics of the magnetic soliton can be controlled by the bilinear interaction and spin-polarized ***,we find that the site-dependent bilinear interaction may break some conserved quantity,and give rise to damping-like effect in the spin evolution.

关键词： Heisenberg spin chain site-dependent bilinear interaction spin-transfer torque magnetic soliton damping effect

First-principles study of structural, mechanical, and electronic properties of W alloying with Zr

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Chinese Physics B 2019年第4期28卷 293-299页

作者： Ning-Ning zhang yu-juan zhang yu Yang Ping zhang Chang-Chun Ge School of Materials Science and Engineering University of Science and Technology Beijing (USTB) LCP Institute of Applied Physics and Computational Mathematics

The structural, mechanical and electronic properties of W_(1-x)Zr_x(x=0.0625, 0.125, 0.1875, 0.25, 0.5) are systematically investigated by means of first-principles calculation. The total-energy calculations demonstrate that the W–Zr binary substitutional solid solution remaining bcc structure can be formed at an atom level. In addition, the derived bulk modulus(B), shear modulus(G), Young's modulus(E) for each of W–Zr alloys decrease gradually with the increase of Zr concentration, suggesting that W alloying with higher Zr concentration becomes softer than pure W metal. Based on the mechanical characteristic B/G ratio, Poisson's ratio υ and Cauchy pressure C, all W_(1-x)Zr_x alloys are regarded as ductile materials. The ductility for each of those materials is improved with the increase of Zr concentration. The calculated density of states indicates that the ductility of W_(1-x)Zr_x is due to the fact that the bonding in the alloy becomes more metallic through increasing the Zr concentration in tungsten. These results provide incontrovertible evidence for the fact that Zr has a significant influence on the properties of W.

关键词： first-principles calculation tungsten zirconium elastic properties

Self-polymerization and co-polymerization kinetics of lead methacrylate

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Rare Metals 2021年第3期40卷 736-742页

作者： yu-juan zhang Xin-Tao Guo Chun-Hong Wang De-Feng Wu Ming zhang School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Department of Materials Research AVIC Manufacturing Technology InstituteBeijing 100024China

Hydrogen nuclear magnetic resonance(H1-NMR) and X-ray diffractometer(XRD) were used to characterize the molecular and crystal structure of lead methacrylate [Pb(MAA)_(2)] which was produced by the double decomposition reaction of lead oxide and methacrylic *** analysis and Kelen-T(u|")dos(K-T) method were used to study the self-polymerization kinetic and the monomer reactivity ratios of Pb(M A A)_(2) and methyl methacrylate(MMA),*** the ternary polymerization method of bulk casting using MMA,Pb(MAA)_(2) and gadolinium methacrylate(Gd(MAA)_(3)) as monomers,we prepared the plexiglass which have neutron and X-ray protection *** results show that the polymerization rate(R_(p)) is expressed as Rp=K[M]^(1.02)[I]^(0.37) below the 10% conversion rate at 70℃,where K is the polymerization rate *** in the N,N-dimethylformamide(DMF) solution,the activation energy required for Pb(MAA)_(2) to initiate self-polymerization by the free radicals is 74.99 kJ·mol^(-1).The reactivity ratios of r1 [Pb(MAA)_(2)] and r2(MMA) are 3.767 *** the thickness of the material increases,the X-ray and thermal neutron shielding ability of the plexiglass containing gadolinium and lead is getting better and better.

关键词： Lead methacrylate Polymerization kinetic Reactivity ratio Plexiglass

Molecular characterization of a defense-related AMP-binding protein gene, OsBIABP1, from rice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第10期10卷 731-739页

作者： Xin-chun zhang Xin yu Hui-juan zhang Feng-ming SONG State Key Laboratory for Rice Biology Institute of Biotechnology Zhejiang University Hangzhou 310029 China

We cloned and characterized a rice gene OsBIABPI encoding an AMP-binding protein. The full-length cDNA of OsBIABP1 is 1912-bp long and is predicted to encode a 558-aa protein. OsBIABP1 contains a typical AMP-binding signature motif and shows high similarity to members of AMP-binding protein family. OsBIABP1 is expressed in stems, leaves and flowers of rice plants, but is not expressed, or expressed at a very low level, in rice roots. The expression of OsBIABP1 was induced by some defense-related signal molecules, e.g., salicylic acid （SA）, benzothiadiazole, jasmonic acid （JA）, and 1-amino cyclopropane- 1-carboxylic acid, which mediate SA- and JA/ethylene （ET）-dependent defense signaling pathways, respectively. Furthermore, the expression of OsBIABP1 is activated by the infection ofMagnaporthe oryzae, and the induced expression is quicker and stronger during early stages ofpathogenesis in incompatible interaction than that in compatible interaction between rice and M. oryzae. Our results suggest that OsBIABP1 may be a defense-related AMP-binding protein that is involved in the regulation of defense response through SA and/or JA/ET signaling pathways.

关键词： Rice Oryza sativa L. Magnaporthe oryzae Defense response OsBIABP1 AMP-binding protein

Comparative analyses of simple sequence repeats(SSRs)in 23 mosquito species genomes:Identification,characterization and distribution(Diptera:Culicidae)

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Insect Science 2019年第4期26卷 607-619页

作者： Xiao-Ting Wang yu-juan zhang Liang Qiao Bin Chen Chongqing Key Laboratory of Vector Insects Chongqing Key Laboratory of Animal BiologyInstitute of Entomology and Molecular BiologyChongqing Normal UniversityChongqingChina

Simple sequence repeats (SSRs) exist in both eukaryotic and prokaryotic genomes and are the most popular genetic markers, but the SSRs of mosquito genomes are still not well understood. In this study, we identified and analyzed the SSRs in 23 mosquito species using Drosophila melanogaster as reference at the whole-genome level. The results show that SSR numbers (33 076-560 175/genome) and genome sizes (574.57-1342.21 Mb) are significantly positively correlated (R~= 0.8992, P < 0.01), but the correlation in individual species varies in these mosquito species. In six types of SSR, mono- to trinucleotide SSRs are dominant with cumulative percentages of 95.14%-99.00% and densities of 195.65/Mb-787.51/Mb, whereas tetra- to hexanucleotide SSRs are rare with 1.12%-4.22% and 3.76/Mb-40.23/Mb. The (A/T)n,(AC/GT)n and (AGC/GCT)n are the most frequent motifs in mononucleotide, dinucleotide and trinucleotide SSRs, respectively, and the motif frequencies of tetra- to hexanucleotide SSRs appear to be species-specific. The 10-20 bp length of SSRs are dominant with the number of 11() 561 ± 93 482 and the frequency of 87.25%± 5.73% on average, and the number and frequency decline with the increase oflength. Most SSRs(83.34%± 7.72%) are located in intergenic regions, followed by intron regions (11.59%± 5.59%), exon regions (3.74%± 1.95%), and untranslated regions (1.32%± 1.39%). The mono-, di- and trinucleotide SSRs are the main SSRs in both gene regions (98.55%± 0.85%) and exon regions (99.27%± 0.52%). An average of 42.52% of total genes contains SSRs, and the preference for SSR occurrenee in different gene subcategories are species-specific. The study provides useful insights into the SSR diversity, characteristics and distribution in 23 mosquito species of genomes.

关键词： characterization comparative analyses distribution mosquito simple sequence repeats(SSRs) whole-genome identification

From beasts to bytes:Revolutionizing zoological research with artificial intelligence

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Zoological Research 2023年第6期44卷 1115-1131页

作者： yu-juan zhang Zeyu Luo Yawen Sun Junhao Liu Zongqing Chen Chongqing Key Laboratory of Vector Insects Chongqing Key Laboratory of Animal BiologyCollege of Life ScienceChongqing Normal UniversityChongqing 401331China School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331China Chongqing National Center for Applied Mathematics Chongqing Normal UniversityChongqing 401331China

Since the late 2010s,Artificial Intelligence(AI)including machine learning,boosted through deep learning,has boomed as a vital tool to leverage computer vision,natural language processing and speech recognition in revolutionizing zoological *** review provides an overview of the primary tasks,core models,datasets,and applications of AI in zoological research,including animal classification,resource conservation,behavior,development,genetics and evolution,breeding and health,disease models,and ***,we explore the challenges and future directions of integrating AI into this *** on numerous case studies,this review outlines various avenues for incorporating AI into zoological research and underscores its potential to enhance our understanding of the intricate relationships that exist within the animal *** we build a bridge between beast and byte realms,this review serves as a resource for envisioning novel AI applications in zoological research that have not yet been explored.

关键词： Animal science Data extraction Classification model Behavior analysis Biomolecular sequences analysis

The Dynamics of a Prey-dependent Consumption Model Concerning Integrated Pest Management

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Acta Mathematica Sinica,English Series 2005年第3期21卷 541-554页

作者： Bing LIU yu juan zhang Lan Sun CHEN Li Hua SUN Department of Mathematics Anshan Normal University Anshan 114005 P. R. China College of Mathematics and Systems Science Xinjiang University Urumqi 830046 P. R. China Deparment of Mathematics Anshan Normal University Anshan 114005 P. R. China Dalian University of Technology Dalian 116024 P. R. China Institute of Mathematics Academy of Mathematics and Systems Science Beijing 100080 P. R. China

A mathematical model for the dynamics of a prey-dependent consumption model concerning integrated pest management is proposed and analyzed. We show that there exists a globally stable pesteradication periodic solution when the impulsive period is less than some critical values. Furthermore, the conditions for the permanence of the system are given. By using bifurcation theory, we show the existence of a nontrival periodic solution if the pest-eradication periodic solution loses its stability. When the unique positive periodic solution loses its stability, numerical simulation shows there is a characteristic sequence of bifurcations, leading to a chaotic dynamics, which implies that dynamical behaviors of prey-dependent consumption concerning integrated pest management are very complex, including period-doubling cascades, chaotic bands with periodic windows, crises, symmetry-breaking bifurcations and supertransients.

关键词： IPM strategy Prey-dependent consumption model Impulsive effect Permanence Chaos

Protective effect of mesenchymal stem cell-derived exosomal treatment of hippocampal neurons against oxygen-glucose deprivation/reperfusion-induced injury

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World Journal of Emergency Medicine 2022年第1期13卷 46-53页

作者： Xiao-fang Guo Shuang-shuang Gu Jun Wang Hao Sun yu-juan zhang Peng-fei yu Jin-song zhang Lei Jiang Department of Emergency the First Affi liated Hospital of Nanjing Medical UniversityNanjing 210029China Key Laboratory of Modern Toxicology Ministry of EducationDepartment of ToxicologySchool of Public HealthNanjing Medical UniversityNanjing 211166China Key Laboratory of Modern Toxicology Ministry of EducationDepartment of Environmental GenomicsSchool of Public HealthNanjing Medical UniversityNanjing 211166China Center for Drug Safety Evaluation and Research Shanghai Institute of Materia MedicaShanghai 201203China

BACKGROUND:Individuals who survive a cardiac arrest often sustain cognitive impairments due to ischemia-reperfusion *** stem cell(MSC)transplantation is used to reduce tissue damage,but exosomes are more stable and highly conserved than *** study was conducted to investigate the therapeutic effects of MSC-derived exosomes(MSC-Exo)on cerebral ischemia-reperfusion injury in an in vitro model of oxygen-glucose deprivation/reperfusion(OGD/R),and to explore the underlying ***:Primary hippocampal neurons obtained from 18-day Sprague-Dawley rat embryos were subjected to OGD/R treatment,with or without MSC-Exo *** integration,cell viability,mitochondrial membrane potential,and generation of reactive oxygen species(ROS)were *** deoxynucleotidyl transferase-mediated 2’-deoxyuridine 5’-triphosphate nickend labeling(TUNEL)staining was performed to detect neuronal ***,mitochondrial function-associated gene expression,Nrf2 translocation,and expression of downstream antioxidant proteins were ***:MSC-Exo attenuated OGD/R-induced neuronal apoptosis and decreased ROS generation(P<0.05).The exosomes reduced OGD/R-induced Nrf2 translocation into the nucleus(2.14±0.65 vs.5.48±1.09,P<0.01)and increased the intracellular expression of antioxidative proteins,including superoxide dismutase and glutathione peroxidase(17.18±0.97 vs.14.40±0.62,and 20.65±2.23 vs.16.44±2.05,respectively;P<0.05 for both).OGD/R significantly impaired the mitochondrial membrane potential and modulated the expression of mitochondrial functionassociated genes,such as PINK,DJ1,LRRK2,Mfn-1,Mfn-2,and *** abovementioned changes were partially reversed by exosomal treatment of the hippocampal ***:MSC-Exo treatment can alleviate OGD/R-induced oxidative stress and dysregulation of mitochondrial function-associated genes in hippocampal ***,MSCExo might be a potential therapeutic strategy to preven

关键词： Mesenchymal stem cells Exosomes Oxygen-glucose deprivation/reperfusion Reactive oxygen species Mitochondria

The intra-neuroendoscopic technique: a new method for rapid removal of acute severe intraventricular hematoma

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Neural Regeneration Research 2018年第6期13卷 999-1006页

作者： Bo Du Ai-Jun Shan yu-juan zhang Jin Wang Kai-Wen Peng Xian-Liang Zhong yu-Ping Peng Department of Neurosurgery Nanfang Hospital Southern Medical University Department of Emergency Medicine Shenzhen People's Hospital The Second Affiliated Hospital of Jinan University

The mortality rate of acute severe intraventricular hematoma is extremely high, and the rate of disability in survivors is high. Intraventricular hematoma has always been a difficult problem for clinical treatment. Although minimally invasive endoscopic hematoma evacuation is widely used to treat this disease, the technique still has room for improvement. Equipment for the intra-neuroendoscopic technique（INET） consists of two of our patented inventions： a transparent sheath（Patent No. ZL 200820046232.0） and a hematoma aspirator（Patent No. ZL 201520248717.8）. This study explored the safety and efficacy of INET by comparing it with extraventricular drainage in combination with urokinase thrombolytic therapy. This trial recruited 65 patients with severe intraventricular hemorrhage, including 35（19 men and 16 women, aged 53.2 ± 8.7 years） in the INET group and 30（17 men and 13 women, aged 51.5 ± 7.9 years） in the control group（extraventricular drainage plus urokinase thrombolytic therapy）. Our results showed that compared with the control group, the INET group exhibited lower intraventricular hemorrhage volumes, shorter intensive care-unit monitoring and ventricular drainage-tube placement times, and fewer incidences of intracranial infection, secondary bleeding, and mortality. Thus, the prognosis of survivors had improved remarkably. These findings indicate that INET is a safe and efficient new method for treating severe intraventricular hematoma. This trial was registered with Clinical ***（NCT02515903）.

关键词： nerve regeneration ventricular hemorrhage transparent sheath extraventricular drainage minimally invasive surgery intra-neuroendoscopic technique urokinase thrombolysis prognosis neural regeneration