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网络条件下列车追踪模型及延迟传播的研究

物理学报 2007年第9期56卷 5158-5164页

作者：荀径宁滨李克平北京交通大学轨道交通控制与安全国家重点实验室北京100044

描述了一种移动闭塞下考虑不同类型列车混跑时基于元胞自动机的列车追踪模型.将该模型应用到铁路网,模拟了网络条件下列车运行情况.应用该模型模拟了移动闭塞下列车延迟传播的现象.分析了发车间隔松弛时间、初始延迟时间等因素对列车延... 详细信息

描述了一种移动闭塞下考虑不同类型列车混跑时基于元胞自动机的列车追踪模型.将该模型应用到铁路网,模拟了网络条件下列车运行情况.应用该模型模拟了移动闭塞下列车延迟传播的现象.分析了发车间隔松弛时间、初始延迟时间等因素对列车延迟的影响.将该模型的模拟结果和理论公式的计算结果进行了比较,验证了模型的可靠性和有效性.

关键词：元胞自动机铁路网络列车追踪模型移动闭塞

Anti-cancer Effect of 20(S)-Ginsenoside-Rh2 on Oral Squamous Cell Carcinoma Cells via the Decrease in ROS and Downregulation of MMP-2 and VEGF

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Biomedical and Environmental Sciences 2020年第9期33卷 713-717页

作者： ZHANG Bao ping li Bo CHENG jing Yang CAO Rui GAO Shu Ting HUANG Chun Juan li Rui ping ning jing liU bin li Zhi Ge School of Stomatology Lanzhou UniversityLanzhou 730000GansuChina Institute of Biomechanics and Medical Engineering Lanzhou UniversityLanzhou 730000GansuChina Department of Stomatology Gansu Provincial HospitalLanzhou 730000GansuChina

Squamous cell carcinoma(SCC) is the most common in oral and maxillofacial regions and occupy more than 90% of the malignant lesions in the oral cavity[1]. The complex anatomy of the head and neck region gives rise to ... 详细信息

关键词： Carcinoma anatomy invasion

Influence of h-BN particle size on fracture behavior and thermal shock resistance of Al2O3-C refractories

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Journal of Iron and Steel Research International 2022年第7期29卷 1129-1137页

作者： Zi-xu Ji Wen-jing liu ning liao Ya-wei li Tian-bin Zhu The State key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina National-Provincial Joint Engineering Research Center of High Temperature Materials and lining Technology Wuhan 430081HubeiChina School of Chemical Engineering Qinghai UniversityXining 810016QinghaiChina

h-BN can be applied in Al_(2)O_(3)–C refractories to substitute graphite due to their similar crystal structure and better resistance to molten steel and *** effects of h-BN particle size on the mechanical properties and fracture behavior of Al_(2)O_(3)–C refractories were investigated through wedge splitting test and microstructural *** obtained results demonstrated that the addition of larger-sized h-BN was conducive to the growth of in situ formed SiC whiskers,which contributed to the highest flexural strength(42.63±3.10 MPa)of specimen *** comparison,the smaller-sized h-BN can induce more crack propagation paths along the interface and within matrix,leading to more tortuous crack propagation paths,and thus the thermal shock-related parameters such as specific fracture energy,characteristic length,and thermal shock resistance were ***,the residual strength ratio of Al_(2)O_(3)–C refractories was increased from 35.5%to 42.5%with decreasing the h-BN particle size from 10 to 0.1μm.

关键词： Al_(2)O_(3)–C refractory h-BN Fracture behavior Thermal shock resistance

Antisense-Mediated Depletion of Tomato Chloroplast Omega-3 Fatty Acid Desaturase Enhances Thermal Tolerance

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Journal of Integrative Plant Biology 2006年第9期48卷 1096-1107页

作者： xun-Yan liu jing-Hua Yang bin li Xiu-Mei Yang Qing-Wei Meng College of life Sciences Key Laboratory of Crop Biology of Shandong Province Shandong Agricultural University Tai＇an 271018 China Department of Horticulture Zhejiang University Hangzhou 310029 China

A chloroplast-localized tomato （Lycopersicon esculentum Mill.） ω-3 fatty acid desaturase gene （LeFADT） was isolated and characterized with regard to its sequence, response to various temperatures, and function in antisense transgenic tomato plants. The deduced amino acid sequence had four histidine-rich regions, of which three regions were highly conserved throughout the whole ω-3 fatty acid desaturasegene family. Southern blotting analysis showed that LeFAD7was encoded by a single copy gene and had two homologous genes in the tomato genome. Northern blot showed that LeFAD7 was expressed in all organs and was especially abundant in leaf tissue. Meanwhile, expression of LeFAD7 was induced by chilling stress （4 ℃）, but was inhibited by high temperature （45 ℃）, in leaves. Transgenic tomato plants were produced by integration of the antisense LeFAD7DNA under the control of a CaMV35S promoter into the genome. Antisense transgenic plants with lower 18 ： 3 content could maintain a higher maximal photochemical efficiency （Fv/Fm） and O2 evolution rate than wild-type plants. These results suggested that silence of the LeFAD7 gene alleviated high-temperature stress. There was also a correlation between the low content of 18 ： 3 resulting from silence of the LeFAD7 gene and tolerance to high-temperature stress.

关键词： chloroplast-localized ω-3 fatty acid desaturase gene expression thermal tolerance tomato (Lycopersicon esculentum) tomato transformation

A New Species of the Asian Toad Genus Megophrys sensu lato(Amphibia: Anura: Megophryidae) from Guizhou Province, China

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Asian Herpetological Research 2018年第4期9卷 224-239页

作者： Shize li ning XU jing liU Jianping JIANG Gang WEI bin WANG Department of Food Science and Engineering Maotai University CAS key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration Biodiversity Conservation key Laboratory of Sichuan Province Chengdu Institute of Biology (CIB) Chinese Academy of Sciences (CAS) Biodiversity Conservation key Laboratory Guiyang College

We describe a new species of the genus Megophrys sensu lato from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent lineage in Megophrys(Panophrys) clade. The new species is distinguished from its congeners by a combination of the following morphological characteristics:(1) small body size with SVL like tubercle at the edge of each upper eyelid;(5) tympanum distinctly visible, rounded;(6) two metacarpal tubercles in hand;(7) relative finger lengths: II bing at bases;(9) heels overlapping when thighs are positioned at right angles to the body;(10) tibiotarsal articulation reaching the level between tympanum to eye when leg stretched forward;(11) an internal single subgular vocal sac in male;(12) in breeding male, the nuptial pads with black nuptial spines on the dorsal bases of the first and second fingers.

关键词： Megophrys sensu lato new species taxonomy phylogenetic analysis Guizhou Province China

Evaluation of elastography combined with serological indexes for hepatic fibrosis in patients with chronic hepatitis B

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World Journal of Gastroenterology 2018年第37期24卷 4272-4280页

作者： bin Xu ning-Ming Zhou Wei-Tian Cao Xiao-jing li Department of ultrasound Fudan University affiliated Shanghai fifth people’s hospital Department of pathology Fudan University affiliated Shanghai fifth people’s hospital

AIM To investigate the value of ultrasound elastography combined with serological indexes in diagnosing liver fibrosis and assessing its *** A total of 338 chronic hepatitis B(CHB) patients were divided into a disease group(patients with hepatic fibrosis) and control group(subjects without hepatic fibrosis). The disease group was further divided into S1-S4 according to the degree of fibrosis. Independent risk factors for hepatic fibrosis were analyzed using multivariate logistic regression. The diagnostic values of hepatic fibrosis from different indicators were compared using receiver operating characteristic(ROC) curves. The combination of elastography and serological indexes was explored to assess the severity of hepatic *** The multivariate logistic regression analysis results revealed that shear wave velocity(SWV), hyaluronic acid(HA), type Ⅳ collagen(CⅣ) and aspartate aminotransferase-to-platelet ratio index(APRI) significantly affected the occurrence of hepatic fibrosis. The ROC curve revealed that the accuracy of the diagnosis of hepatic fibrosis for SWV and HA were 87.3% and 84.8%, respectively. The accuracy of SWV combined with HA was 88.9%. The multiple linear regression analysis revealed that SWV, aspartate aminotransferase(AST)/alanine aminotransferase(ALT), HA, CⅣ, APRI and fibrosis index based on the 4 factor(FIB-4) were screened as statistically significant independent factors. The established regression equation was: Fibrosis level =-4.046 + 1.024 × SWV + 1.170 × AST/ALT + 0.011 × HA + 0.020 × CⅣ + 0.719 × APRI + 0.379 × FIB-4. CONCLUSION SWV combined with serological indexes can improve the accuracy of diagnosis for CHB hepatic fibrosis. Serum indexes can help diagnose the degree of hepatic fibrosis.

关键词： Elastography Serology Hepatic fibrosis Non-invasive diagnosis

A New Species of the Asi an Toad Genus Megophrys sensu lato (Anura: Megophryidae) from Guizhou Province, China

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Asian Herpetological Research 2020年第1期11卷 1-18页

作者： jing liU Shize li Gang WEI ning XU Yanlin CHENG bin WANG Jun WU Department of Resources and Environment Moutai InstituteRenhuai 564500China Nanjing Institute of Environmental Sciences Ministry of Ecology and Environment of ChinaNanjing 210042China Biodiversity Conservation key Laboratory Guiyang CollegeGuiyang 550002China Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China

We describe a new species of the genus Megophr ys from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent clade nested into the Megophrys clade and sister to M. minor. On morphology,the new species is distinguished from its congeners by a combination of the following characters:(1) small body size with SVL like tubercle at the edge of each upper eyelid;(5) tympanum distinctly visible, rounded;(6) two or three metacarpal tubercles in hand;(7) relative finger lengths: Ⅰbing;(9) heels overlapped when thighs are positioned at right angles to the body;(10) tibiotarsal articulation reaching tympanum to eye when leg stretched forward;(11) an internal single subgular vocal sac in male;(12) in breeding male, the nuptial pads with black nuptial spines on the dorsal bases of the first and second fingers.

关键词： Taxonomy new species molecular phylogenetic analysis morphology China

Expression and characterization of a codon-optimized butyrylcholinesterase for analysis of organophosphate insecticide residues

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Journal of Integrative Agriculture 2016年第3期15卷 684-693页

作者： TIAN jing-jing CHEN Xiang-ning XIE Yuan-hong LU Yong XU Wen-tao XU li DU bin College of Food Science and Engineering Beijing University of Agriculture Beijing 102206 P.R. China Beijing Food Safety Monitoring Center Beijing 100041 P.R.China College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 P.R. China

Organophosphate insecticide residues on vegetable, fruit, tea and even grains are primary cause of food poisoning. Organophosphate compounds can cause irreversible inhibition of the activity of acetylcholinesterase and butyrylcholinesterase（BChE, EC 3.***.1.8）, which are both candidates for rapid detection of organophosphate pesticides. To develop an easy-tohandle method for detecting organophosphate pesticides using BChE, BChE from human was optimized according to the codon usage bias of Pichia pastoris and successfully expressed in P. pastoris GS115. The codon-optimized cDNA shared 37.3% of the codon identity with the native one. However, the amino acid sequence was identical to that of the native human butyrylcholinesterase gene（h BCh E） as published. The ratio of guanine and cytosine in four kinds of bases（（G＋C） ratio） was simultaneously increased from 40 to 47%. The recombinant hBChE expression reached a total protein concentration of 292 mg m L^–1 with an activity of 14.7 U m L^–1, which was purified 3.2×10^3-fold via nickel affinity chromatography with a yield of 68% and a specific activity of 8.1 U mg^–1. Recombinant hBChE was optimally active at pH 7.4 and 50°C and exhibited high activity at a wide pH range（〉60% activity at pH 4.0 to 8.0）. Moreover, it had a good adaptability to high temperature（〉60% activity at both 50 and 60°C up to 60 min） and good stability at 70°C. The enzyme can be activated by li^＋, Co^＋, Zn^2＋ and ethylene diamine tetraacetic acid（EDTA）, but inhibited by Mg^2＋, Mn^2＋, Fe^2＋, Ag^＋ and Ca^2＋. Na^＋ had little effect on its activity. The values of h BChE of the Michaelis constant（Km） and maximum reaction velocity（Vm） were 89.4 mmol L^–1 and 1 721 mmol min^–1 mg^–1, respectively. The bim olecular rate constants（K_i） of the hBChE to four pesticides were similar with that of electric eel AChE（EeAChE） and higher than that of horse BChE（HoBChE）. All vlues of the half maximal inhibitory concentration of a substance（IC50） for hBChE were lower th

关键词： butyrylcholinesterase organophosphate insecticide residues Pichia pastoris expression codon-optimized

Multiple Mild Stimulations Reduce Membrane Distribution of CX3CR1 Promoted by Annexin al in Microglia to Attenuate Excessive Dendritic Spine Pruning and Cognitive Deficits Caused by a Transient Ischemic Attack in Mice

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Neuroscience Bulletin 2022年第7期38卷 753-768页

作者： Lu Zheng Yi Wang bin Shao Huijuan Zhou Xing li Cai Zhang ning Sun jing Shi Department of Neurobiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China key Laboratory of Neurological Diseases Ministry of EducationWuhan 430030China The Institute for Brain Research Collaborative Innovation and TechnologyWuhan 430030China Center for Brain Science Huazhong University of Science Department of Clinical LaboratoryThe First Affliated Hospital of Zhengzhou UniversityZhengzhou 450052China Department of Immunology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

A transient ischemic attack(TIA)can cause reversible and delayed impairment of cognition,but the specific mechanisms arestill *** al(ANXA1)is a phospholipid-binding ***,we confirmed that cognition and hippocampal synapses were impaired in TIA-treated mice,and this could be rescued by multiple mild stimulations(MMS).TIA promoted the interaction of ANXAl and CX3CR1,increased the membrane distribution of CX3CR1 in microglila,and thus enhanced the CX3CR1 and CX3CL1 *** phenomena induced by TIA could be reversed by ***,the CX3CR1 membrane distribution and CX3CR1-CX3CL1 interaction were upregulated in primary cultured microglia overexpressing ANXAl,and the spine density was significantly reduced in co-cultured microglia overexpressing ANXAl and ***,ANXAl overexpression in microglia abolished the protection of MMS after ***,our study provides a potential strategy for treating the delayed synaptic injury caused by TIA.

关键词： Annexin al CX3CR1 Microglia Dendritic spine pruning Transient ischemic attack Multiple mild stimulations