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Au doping effects on electrical and optical properties of vanadium dioxides

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Science China(Physics,Mechanics & Astronomy) 2012年第3期55卷 409-412页

作者： YaBin Zhu Fan He jie na Beijing Jiaotong Univ Sch Sci Beijing 100044 Peoples R China

Vanadium dioxides were fabricated on normal glass substrates using reactive radio frequency （RF） magnetron sputtering. The oxygen flow volume and annealed temperatures as growth parameters are systematically investigated. The electrical and opti- cal properties of VO2 and Au：VO2 thin films with different growth conditions are discussed. The semiconductor-metal phase transition temperature decreased by -10~C for the sample with Au doping compared to the sample without Au doping. How- ever, the optical transmittance of Au：VO2 thin films is much lower than that of bare VO2. These results show that Au doping has a marked effect on the electrical and optical properties.

关键词： VO2 thin film transmittance semiconductor-metal phase transition

水磷配施对紫花苜蓿叶片特征及氮磷计量比的影响

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草地学报 2024年第8期32卷 2484-2497页

作者：李婕娜冯甘霖庞晓攀魏小星刘慧霞兰州大学草地农业科技学院甘肃兰州730020 青海大学畜牧兽医科学院青海西宁810016 西北民族大学生命科学与工程学院甘肃兰州730030

灌溉和磷添加是维持紫花苜蓿(Medicago sativa)高产稳产的重要管理措施。本研究通过盆栽试验,设置不同磷添加量(0,64,127和191 mg·kg^(-1))和灌溉量(40%~45%,60%~65%和80%~85%土壤饱和含水量),探究水磷配施对紫花苜蓿叶片特征及叶片氮... 详细信息

灌溉和磷添加是维持紫花苜蓿(Medicago sativa)高产稳产的重要管理措施。本研究通过盆栽试验,设置不同磷添加量(0,64,127和191 mg·kg^(-1))和灌溉量(40%~45%,60%~65%和80%~85%土壤饱和含水量),探究水磷配施对紫花苜蓿叶片特征及叶片氮磷比的影响。结果表明:随灌溉量增加,紫花苜蓿叶宽、叶面积和比叶面积均显著增加(P<0.05),叶片氮磷比由14.23~15.33降低至10.99~13.43;磷添加量对叶面积、叶片氮磷比均有显著影响(P<0.05),且不同茬次对磷添加的响应规律具有分异性;水磷配施极显著影响紫花苜蓿叶片氮磷生态化学计量比(P<0.01)。当土壤饱和含水量为60%~65%的灌溉量和127 mg·kg^(-1)的磷添加量下,能有效改善紫花苜蓿叶片特征,缓解紫花苜蓿受氮限制状态,由受氮磷共同限制转变为仅受氮限制,说明从叶片特征和氮磷化学计量角度,理论上存在最佳水磷配施组合以改善紫花苜蓿生长。

关键词：水磷配施紫花苜蓿叶片特征氮磷计量比最佳理论组合

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Inhibiting effect of melittin on pathogens of crops

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Chinese Science Bulletin 2007年第5期52卷 639-644页

作者： PAN LingZi na jie XING Zhuo FANG HongJun WANG GuanLin College of Life Science Liaoning Normal University Dalian 116029 China

The spectrum of antimicrobial effects of melittin were investigated on 19 pathogens by using a cylin-der-plate method with serial dilutions. Bacteriostatic efficiency and possible mechanistic effects were monitored via growth curves. The mechanism of inhibition was further analyzed by SDS-PAGE, flow cytometry and electron microscopy. Melittin had a wide inhibition spectrum and killed pathogens ef-fectively, and bacteriostatic action was influenced by factors such as pH and temperature. We eluci-dated three inhibitory mechanisms: melittin integrated with the cell membrane causing cell bursting and cytoplasm release, inhibited the synthesis of proteins and caused the cytoplasm to condense, and delayed pathogens in phase I (or phase G1) so that they could not complete the cell cycle. These re-sults suggest that melittin could serve as a broad-spectrum biological pesticide with fast-action and high-efficiency.

关键词：蜂毒肽作物病原菌抑制作用抑菌机制抗菌谱

Aneuploidy in pluripotent stem cells and implications for cancerous transformation

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Protein & Cell 2014年第8期5卷 569-579页

作者： jie na Duncan Baker Jing Zhang Peter W. Andrews Ivana Barbaric School of Medicine Tsinghua University Beijing 100084 China Sheffield Diagnostic Genetic Services Sheffield Children's Hospital Sheffield S10 2TH UK Centre for Stem Cell Biology Department of Biomedical Science The University of Sheffield Sheffield S10 2TN UK

Owing to a unique set of attributes, human pluripotent stem cells （hPSCs） have emerged as a promising cell source for regenerative medicine, disease modeling and drug discovery. Assurance of genetic stability over long term maintenance of hPSCs is pivotal in this endeavor, but hPSCs can adapt to life in culture by acquiring non-random genetic changes that render them more robust and easier to grow. In separate studies between 12.5% and 34% of hPSC lines were found to acquire chromosome abnormalities over time, with the incidence increasing with passage number. The predominant genetic changes found in hPSC lines involve changes in chromosome number and structure （particularly of chromosomes 1, 12, 17 and 20）, remi- niscent of the changes observed in cancer cells. In this review, we summarize current knowledge on the causes and consequences of aneuploidy in hPSCs and highlight the potential links with genetic changes observed in human cancers and early embryos. We point to the need for comprehensive characterization of mechanisms underpinning both the acquisition of chromosomal abnormalities and selection pressures, which allow mutations to persist in hPSC cultures. Elucidation of these mechanisms will help to design culture conditions that minimize the appearance of aneuploid hPSCs. Moreover, aneuploidy in hPSCs may provide a unique platform to analyse the driving for- ces behind the genome evolution that may eventually lead to cancerous transformation.

关键词： human pluripotent stem cells (hPSCs),culture adaptation aneuploidy cancer genetic changes

Ultrastructural observation on sterilization of melittin

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Science China(Life Sciences) 2011年第2期54卷 166-170页

作者： WANG GuanLin na jie PAN LingZi XING Zhuo FANG HongJun College of Life Science Liaoning Normal University Dalian 116029 China

The effects of melittin on growth and bacteriostasis of four pathogens were extensively investigated using scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The results indicated that the melittin had a marked bacteriostatic effect on the four pathogenic *** these,*** was influenced most powerfully and quickly,the yeast and *** were the second,and the *** was inhibited by a low concentration but was killed by a high *** was observed in the experiments that melittin killed pathogenic bacteria in three *** was by pore *** integrating melittin into the plasma membrane,a vacuole was formed then penetrated,resulting in bacterial content *** vacuole also experienced plasmolysis and the growing cavity destroyed the membrane.A third effect was the formation of vacuoles in the cells which induced the pycnosis of the cytoplasm resulting in a cell *** mechanism of melittin bacteriostasis was the result of integrating melittin with phospholipod double layers of the plasmalemma and the endomembranes.

关键词： Melittin pathogens ultrastructural alterations bacteriostasis mechanism

Positive periodic solutions of higher-dimensional nonlinear functional difference equations

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Journal of Central South University of Technology 2005年第Z1期12卷 274-277页

作者： DAI Bin-xiang ZOU jie-zhong ZHANG na School of Mathematical Science and Computing Technology Central South University Changsha 410075 China School of Mathematical Science and Computing Technology Central South University Changsha 410075 China College of Mathematics and Econometrics Hunan University Changsha 410082 China

In this paper, we apply a cone theoretic fixed point theorem to obtain sufficient conditions for the existence of multiple positive periodic solutions to the higher-dimensional functional difference equations of the f... 详细信息

关键词： positive periodic solution difference equations cone fixed point theorem

Differential regulation of H3S10 phosphorylation, mitosis progression and cell fate by Aurora Kinase B and C in mouse preimplantation embryos

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Protein & Cell 2017年第9期8卷 662-674页

作者： Wenzhi Li Peizhe Wang Bingjie Zhang Jing Zhang Jia Ming Wei Xie jie na Center for Stem Cell Biology and Regenerative Medicine School of Medicine Tsinghua University Beijing 100084 China Center for Stem Cell Biology and Regenerative Medicine MOE Key Laboratory of Bioinformatics THU-PKU Center for LifeSciences School of Life Sciences Tsinghua University Beijing 100084 China

Coordination of cell division and cell fate is crucial for the successful development of mammalian early embryos. Aurora kinases are evolutionarily conserved serine/threonine kinases and key regulators of mitosis. Aurora kinase B （AurkB） is ubiquitously expressed while Aurora kinase C （AurkC） is specifically expressed in gametes and preimplantation embryos. We found that increasing AurkC level in one blastomere of the 2-cell embryo accelerated cell division and decreasing AurkC level slowed down mitosis. Changing AurkB level had the opposite effect. The kinase domains of AurkB and AurkC were responsible for their different ability to phosphorylate Histone H3 Serine 10 （H3S10P） and regulate metaphase timing. Using an Oct4-photoactivat- able GFP fusion protein （Oct4-paGFP） and fluorescence decay after photoactivation assay, we found that AurkB overexpression reduced Oct4 retention in the nucleus. Finally, we show that blastomeres with higher AurkC level elevated pluripotency gene expression, which were inclined to enter the inner cell mass lineage and subsequently contributed to the embryo proper. Collectively, our results are the first demonstration that the activity of mitotic kinases can influence cell fate decisions in mammalian preimplantation embryos and have important implications to assisted reproduction.

关键词： Aurora kinase mouse preimplantation embryo cell fate development mitosis

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秦岭雄性大熊猫繁殖行为监测与种公兽培育

动物医学进展 2024年第7期45卷 130-134页

作者：赵鹏鹏赵卫平张丹辉沈洁娜雷颖虎秦岭大熊猫研究中心(陕西省珍稀野生动物救护基地) 陕西西安710402

提高大熊猫的人工繁育水平是维持大熊猫圈养种群数量的关键。圈养大熊猫的选择性择偶交配和自然交配受孕率低是制约秦岭大熊猫圈养繁殖的主要因素,而种公兽的成功培育是提高圈养繁殖的重要环节。本研究通过对4只秦岭大熊猫雄性个体进行... 详细信息

提高大熊猫的人工繁育水平是维持大熊猫圈养种群数量的关键。圈养大熊猫的选择性择偶交配和自然交配受孕率低是制约秦岭大熊猫圈养繁殖的主要因素,而种公兽的成功培育是提高圈养繁殖的重要环节。本研究通过对4只秦岭大熊猫雄性个体进行健康状态评估、体重和粪便量监测、精子质量检测、日常行为和繁殖行为培训以及最佳放对时间确定等试验,成功培育大熊猫种公兽2只,5年期间成功繁育幼仔15胎21仔,受孕率由2018年的20%上升到2022年的66.7%。研究结果为大熊猫种公兽培育技术推广、提高圈养大熊猫繁育数量提供了重要参考。

关键词：秦岭大熊猫种公兽培育繁殖行为监测

Characterization of Porcine Reproductive and Respiratory Syndrome Virus Deletion Mutant

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Agricultural Sciences in China 2008年第11期7卷 1379-1386页

作者： CHEN Hao-tai ZHANG jie MA Li-na LIU Yong-sheng State Key Laboratory of Veterinary Etiological Biology/Key Laboratory of Animal Virology Ministry of Agriculture/Key Laboratory of Veterinary Public Health Ministry of Agriculture/Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences Lanzhou 730046 P.R.China

The genome of the isolate of porcine reproductive and respiratory syndrome virus （PRRSV） from China, designated HPBEDV, was sequenced and analyzed. The size of the genome of HPBEDV was 15 334 nucleotides （nt）. Comparative analysis of HPBEDV with the genomic sequences of the domestic and other isolates （JXA 1, HUN4, CH-1 a, B J-4, VR2332, and LV） revealed that HPBEDV shared 98.4, 98.0, 89.0, 88.7, and 88.6% identity with the American strain JXA1, HUN4, CH- 1a, BJ-4, and VR2332, respectively, but only 54.7% identity with the European reference strain Lelystad virus. The NSP2 gene had 2 850 nt and encoded 950 amino acids （aa）, with two discontiguous deletions of 1 aa and 29 aa at positions 482 and 534-562, respectively, relative to VR-2332. Also, phylogenetic analysis with the published PRRSV genomic sequences indicated that the newly emerging isolate form a clade with the VR-2332 isolates. Therefore, HPBEDV was a novel strain with deletions in NSP2 gene.

关键词： porcine reproductive and respiratory syndrome virus deletion mutant genome phylogenetic tree