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Soil carbon, Nitrogen and Microbial Dynamics of Pasturelands: Impacts of Grazing Intensity and Planting Systems

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Pedosphere 2014年第3期24卷 408-416页

作者： WANG yi DUAN Wen-Xia c.TU S.WASHBURN cHENG Lei S.HU State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Department of Plant Pathology North Carolina State University Sichuan Tourism University Department of Animal Science North Carolina State University

Management intensity critically influences the productivity and sustainability of pasture systems through modifying soil microbes, and soil carbon （c） and nutrient dynamics; however, such effects are not well understood yet ir the southeastern USA. We examined the effects of grazing intensity and grass planting system on soil c and nitrogen （N） dynamics, and microbial biomass and respiration in a long-term field experiment in Goldsboro, North carolina, USA. A split-plot experiment was initiated in 2003 on a highly sandy soil under treatments of two grass planting systems （ryegrass rotation with sorghum-sudangrass hybrid and ryegrass seeding into a perennial bermudagrass stand） at low and high grazing densities. After 4 years of continuous treatments, soil total c and N contents across the 0 30 cm soil profile were 24.7% and 17.5% higher at the high than at the low grazing intensity, likely through promoting plant productivity and c allocation belowground as well as fecal and urinary inputs. Grass planting system effects were significant only at the low grazing intensity, with soil c, N, and microbial biomass and respiration in the top 10 cm being higher under the ryegrass/bermudagrass than under the ryegrass/sorghum-sudangrass hybrid planting systems. These results suggest that effective management could mitigate potential adverse effects of high grazing intensities on soil properties and facilitate sustainability of pastureland.

关键词： c allocation grass species microbial respiration microbial biomass pastureland sustainability plant productivity

川芎嗪含药血清通过抑制抗氧化能力在肝癌HepG2细胞中发挥抗肿瘤作用

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医学分子生物学杂志 2025年第1期22卷 35-40页

作者：张义芳戴毅遂宁市中心医院肝胆外科四川省遂宁市629000

目的探究川芎嗪(tetramethylpyrazine,TMP)含药血清对肝癌细胞增殖的影响及其机制。方法制备SD大鼠0、30、60、120 mg/kg TMP含药血清,并分别处理HepG2细胞,克隆形成和ccK-8法检测HepG2细胞的增殖;流式细胞术检测HepG2细胞周期和凋亡,流... 详细信息

目的探究川芎嗪(tetramethylpyrazine,TMP)含药血清对肝癌细胞增殖的影响及其机制。方法制备SD大鼠0、30、60、120 mg/kg TMP含药血清,并分别处理HepG2细胞,克隆形成和ccK-8法检测HepG2细胞的增殖;流式细胞术检测HepG2细胞周期和凋亡,流式Jc-1检测HepG2细胞线粒体膜电位变化,蛋白质印迹检测HepG2细胞中PcNA、P27、cleaved caspase-3(cas-3),Bax,Bcl-2和cyt c的表达;试剂盒检测HepG2细胞中SOD和MDA的含量;2,7-二氯二乙酸酯(DcFH-DA)测定HepG2细胞中活性氧(reactive oxygen species,ROS)的产生。结果与对照组比较,TMP 60、120 mg/kg组细胞增殖能力受抑制,细胞周期受阻滞;凋亡率明显升高;抗氧化能力受抑制。结论TMP可抑制肝癌细胞的增殖,并通过线粒体依赖途径诱导肝癌细胞凋亡,刺激ROS的生成降低癌细胞抗氧化能力,从而抑制肝癌的发展。

关键词：肝癌川芎嗪增殖细胞凋亡线粒体活性氧

Numerical modeling for a simulated rockburst experiment using LS-DYNA

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Underground Space 2021年第2期6卷 153-162页

作者： c.P.yi E.Nordlund P.Zhang S.Warema S.Shirzadegan Division of Mining and Rock Mechanics Lulea University of TechnologySweden

Ground support systems are commonly used to mitigate the potential consequences of rockburst in burst prone *** assess the capacity of ground support systems when subjected to dynamic loading,simulated rockburst tests using blasting were conducted at the Kiruna *** this study,a numerical simulation for one of the field tests was conducted using the LS-DYNA code to investigate the dynamic response of the ground support systems including shotcrete and *** numerical results showed a similar particle vibration pattern and a crack pattern to those of the field *** effects of the detonator position and the charge configuration on the dynamic response of ground support systems are also *** results indicated that the peak particle vibrations on the tested panel increase along the direction of detonation *** is difficult to use different charge concentrations in one borehole to investigate the effect of different dynamic loads on the dynamic response of support *** results also indicated that 2D numerical modeling for simulated rockburst experiments could overestimate the dynamic response of ground support systems.

关键词： Simulated rockburst experiments Ground support systems Numerical modeling

Y-branched TiO_2 nanotube arrays synthesized by anodic oxidation

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Science china(Physics,Mechanics & Astronomy) 2012年第1期55卷 14-18页

作者： YANG Xu Qu yi FAN yi LIU XingYuan National Key Lab of High Power Semiconductor Lasers Changchun University of Science and Technology Changchun 130022 China Key Laboratory of Excited State Processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China

We report a novel synthesis strategy for Y-branched TiOe nanotubes on a pure titanium foil by electrochemical anodic oxida- tion in an NH4F organic electrolyte. Effects of temperature range, oxidation time, and morphology-dependent parameters of the Y-branched TiO2 nanotube arrays were investigated. We found that an optimized growth-temperature window between 20℃ and 30℃ resulted in Y-branched nanotubes with much better morphology and photoelectric performances. After annealing at 450℃ for 1.5 h in air, a dominant crystal structure of these arrays was indexed to anatase.

关键词： Y-branched TiO2 nanotube anodization oxidation temperature anatase

Solving Master Equation for Two-Mode Density Matrices by Virtue of ThermalEntangled State Representation

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communications in Theoretical Physics 2004年第1期41卷 21-24页

作者： FANHong-yi LIchao DepartmentofMaterialScienceandEngineering UniversityofScienceandTechnologyofChinaHefei230026China DepartmentofSpecialclassfortheGiftedYoung UniversityofScienceandTechnologyofChinaHefei230026China

We extend the approach of solving master equations for density matrices by projecting it onto the thermal entangled state representation(Hong-yi Fan and Jun-Hua chen,***.A35(2002)6873)to two-mode *** this approach the two-photon master equations can be directly and conveniently converted into c-number partial differential *** an example,we solve the typical master equation for two-photon process in some limiting cases.

关键词： thermal entangled state master equation

Non-alkyl tin-oxo clusters as new-type patterning materials for nanolithography

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Science china chemistry 2022年第1期65卷 114-119页

作者： Di Wang Xiaofeng yi Lei Zhang State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of chinese Academy of Sciences Beijing 100049China

Nanolithography plays crucial roles in the miniaturization of dense integrated circuit,which extremely depends on innovative resist ***,metal-containing resists have been explored due to their higher short-wavelength photon absorption than traditional polymer ***,for the first time,the patterning performance of non-alkyl tin-oxo clusters has been ***,the influence of structural characteristics on resolution and sensitivity has been *** evaluate the surface ligand effect,three non-alkyl Sn_(10)-oxo clusters with the same core were functionalized with pyrazole,3-methylpyrazole and 4-methylpyrazole,***,another Sn_(14)-oxo cluster with similar core configuration was also prepared using 4-methylpyrazole ligand to study the influence of Sn ***-coating method was then applied to fabricate thin films of these non-alkyl tin-oxo clusters on Si substrate,which showed various thicknesses and *** interestingly,electron beam lithography(EBL)patterning studies indicated that for the same Sn_(10)core,the 4-methylpyrazoledecorated clusters showed the best *** for the different cluster cores with the same 4-methylpyrazole ligand,the patterns of Sn_(10)with the higher ligand:Sn ratio are also better than those of Sn_(14).Finally,distinguishable 50 nm resolution was achieved by 4-methylpyrazole-decorated Sn_(10)at expose energy of 100μc/cm2which can be significantly improved by increasing expose energy to 1,000μc/cm2as confirmed by atomic force microscopy(AFM)*** work not only opens the nanolithography applications of non-alkyl tin-oxo clusters,but also provides an effective structural methodology for improving their patterning performance in future.

关键词： non-alkyl tin-oxo clusters nanolithography ligands effect EBL patterning materials

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Unraveling structure and performance of protein a ligands at liquid–solid interfaces: A multi-techniques analysis

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chinese Journal of chemical Engineering 2023年第2期54卷 232-239页

作者： yi Shen Xinshuang chu Qinghong Shi Department of Biochemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Key Laboratory of Systems Bioengineering and Frontiers Science center for Synthetic Biology(Ministry of Education) Tianjin UniversityTianjin 300350China

Oriented ligand immobilization is one of the most effective strategies used in the design and construction of a high-capacity protein A chromatography. In this work, cysteine was introduced as anchoring sites by substituting a specific residue on Helix Ⅰ, Ⅱ, and at c-terminus of antibody binding domain Z from protein A, respectively, to investigate structural evolution and binding behavior of protein A ligands at liquid-solid interfaces. Among the three affinity dextran-coated Fe_(3)O_(4) magnetic nanoparticles(Fe_(3)O_(4)@Dx MNPs), affinity MNPs with the immobilized ligand via N11c on Helix Ⅰ(Fe_(3)O_(4)@Dx-Z_(1) MNPs) had the highest helical content, and MNPs with the immobilized ligand via G29c on Helix Ⅱ(Fe_(3)O_(4)@Dx-Z_(2) MNPs) had the lowest helical content at the same pHs. It was attributed to less electrostatic attraction of ligand to negatively charged surface on Fe_(3)O_(4)@Dx-Z_(1) MNPs because of less positive charged residues on Helix Ⅰ(K6) than Helix Ⅱ(R27/K35). Among the three affinity MNPs, moreover, the highest affinity to immunoglobulin G(IgG) binding was observed on Fe_(3)O_(4)@Dx-Z_(1) MNPs in isothermal titration calorimetry measurement, further validating greater structural integrity of the ligand on Fe_(3)O_(4)@Dx-Z_(1) MNPs. Finally,the study of IgG binding on MNPs and 96-well plates showed that anchoring sites for ligand immobilization had distinct influences on IgG binding and IgG-mediated antigen binding. This work illustrated that anchoring sites of the ligands had a striking significance for the molecular structure of the ligand at liquid-solid interfaces and raised an important implication for the design and optimization of protein A chromatography and protein A-based immunoassay analysis.

关键词： Adsorption Interface Thermodynamics Protein A ligand Immobilization Molecular structure

Limiting current oxygen sensor based on Y,In co-doped SrTiO_(3)as a dense diffusion barrier layer

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Nano Research 2022年第6期15卷 4880-4885页

作者： Ke Shan Zhongzhou yi Jing Wang college of Science Honghe UniversityMengzi 661199China

A novel dense diffusion barrier material(Y_(x)Sr_(1−x)Ti_(0.9)In_(0.1)O_(3−δ)(x=0.03,0.05,0.07))was prepared by using a sol-gel *** crystal structure,microstructures,electrical conductivity and ionic conductivity of barrier material were *** results show that the samples exhibit the formation of cubic perovskite structure *** increase of Y-doping amount on A-site improved electrical conductivity and sinterability of materials.A limiting current oxygen sensor based on Y_(0.07)Sr_(0.97)Ti_(0.9)In_(0.1)O_(3–δ)as a dense diffusion barrier shows excellent sensing *** linear relationship between limiting current logIL and 1000/T can described logIL=4.603,8−3.847,5·1,000/*** 750°c,0.25%≤x(O_(2))≤5.0%,the linear relationship between limiting current(IL)and oxygen amount(x(O_(2)))can described as I_(L)=7.047,6+3.875,1·x(O_(2)).

关键词： limiting current oxygen sensor dense diffusion barrier strontium titanate mixed conductivity

MOLEcULAR cLONING AND cHARAcTERIZATION OF THE cDNA cODING FOR HEPATITIS B VIRUS SURFAcE ANTIGEN

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Science china chemistry 1985年第1期28卷 49-59页

作者：何葆光,JOSEPH L. MELNIcK,ALEEM SIDDIQUI,WILLIAM S. ROBINSON,SIMON W. LAW,eugene c. LAI Shanghai Institute of Biological Products Ministry of Public Health PRc Department of Virology and Epidemiology Baylor colleye of Medicine USA Department of Medicine Stanford University School of Medicine USA Department of Medicine Stanford University School of Medicine USA Department of cell Biology Baylor college of Medicine USA Department of cell Biology Baylor college of Medicine USA

Hepatitis B virus surface antigen （HBsAg） inRNA has been enriched from a hepatoma cell line （PLc/PRF/5） by specific polysome immunoprecipitation and used for cDNA cloning. A HBsAg cDNA clone was identified by in situ hybridization with a cloned viral probe. It was characterized by restriction endonuclease mapping and DNA sequence analysis. Molecular hybridization of PLc/PRF/5 cellular DNA and RNA to [32P]-labeled HBsAg cDNA revealed the integration of at least six copies of the hepatitis B virus （HBV） DNA into the host genome and expression of three DNA species confining HBsAg-specific sequences. The possible role of HBV in the oncogenesis of primary hepatocellular carcinoma is discussed.

关键词： DNA RNA HBsAg MOLEcULAR cLONING AND cHARAcTERIZATION OF THE cDNA cODING FOR HEPATITIS B VIRUS SURFAcE ANTIGEN