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In situ luminescence measurements of GaN/Al_(2)O_(3) film under different energy proton irradiations

Chinese Physics B 2024年第5期33卷 704-710页

作者：蒋文丽欧阳潇仇猛淋英敏菊陈琳庞盼张春雷张耀锋廖斌 Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within the *** energies of H^(+)were set to 500 keV,640 keV and 2 MeV,the Bragg peaks of which correspond to the GaN film,GaN/Al_(2)O_(3) heterojunction and Al_(2)O_(3) substrate,respectively.A photoluminescence measurement at 250 K was also performed for comparison,during which only near band edge(NBE) and yellow band luminescence in the GaN film were *** evolution of the luminescence of the NBE and yellow band in the GaN film was discussed,and both exhibited a decrease with the fluence of H^(+).Additionally,the luminescence of F centers,induced by oxygen vacancies,and Cr^(3+),resulting from the ^(2)E →^(4)A_(2) radiative transition in Al_(2)O_(3),were measured using 2 MeV H^(+).The luminescence intensity of F centers increases gradually with the fluence of H^(+).The luminescence evolution of Cr^(3+)is consistent with a yellow band center,attributed to its weak intensity,and it is situated within the emission band of the yellow band in the GaN *** results show that IBIL measurement can effectively detect the luminescence behavior of multilayer films by adjusting the ion *** measurement can be excited by various techniques,but IBIL can satisfy in situ luminescence measurement,and multilayer structural materials of tens of micrometers can be measured through IBIL by adjusting the energy of the inducing *** evolution of defects at different layers with ion fluence can be obtained.

关键词： ion beam-induced luminescence(IBIL) GaN/Al_(2)O_(3) ion beam

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矩形水凝胶微凹槽的空间约束调控人脐静脉内皮细胞的形态和排列

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四川大学学报（医学版） 2024年第1期55卷 87-94页

作者：江文丽钟健欧阳智沈钧怡邱艳曾烨四川大学华西基础医学与法医学院生物医学工程研究室成都610041

目的本研究拟构建微米级矩形水凝胶凹槽,探究人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)在三维空间约束条件下的形态和排列规律。方法使用四臂-聚乙二醇-丙烯酸酯水凝胶制备宽度为60μm、100μm、140μm的矩形... 详细信息

目的本研究拟构建微米级矩形水凝胶凹槽,探究人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)在三维空间约束条件下的形态和排列规律。方法使用四臂-聚乙二醇-丙烯酸酯水凝胶制备宽度为60μm、100μm、140μm的矩形微凹槽,检测其尺寸和纤连蛋白(fibronectin,FN)黏附情况;在FN包被的微凹槽中接种HUVECs,培养48 h后检测细胞的形态和取向,利用鬼笔环肽标记细胞骨架和激光共聚焦显微镜观察水凝胶微凹槽中HUVECs细胞骨架取向,以无微图案平面为对照。结果构建的水凝胶微凹槽形态均一、结构完整,边缘清晰,宽度误差<3.5%,不同宽度水凝胶微凹槽的深度差异较小,FN黏附均匀,为细胞提供了微图案化的生长界面。对照组中细胞排列杂乱,取向随机,细胞取向角为(46.9±1.8)°,而水凝胶微凹槽中细胞取向角显著减小(P<0.001),但随着水凝胶微凹槽宽度增加而增大,60μm、100μm、140μm水凝胶微凹槽中细胞取向角分别为(16.4±2.8)°、(24.5±3.2)°、(30.3±3.5)°;与对照组相比较(35.7%),不同宽度水凝胶微凹槽中取向角<30°的细胞数量增多(P<0.001),但随着水凝胶微凹槽宽度增加,取向角<30°的细胞数量逐渐减少(79.9%、62.3%、54.7%),而取向角60°~90°的细胞数量逐渐增加(P<0.001)。微凹槽中细胞胞体变小、变圆,细胞沿微凹槽方向排列,细胞骨架排列发生相应改变,对照组中细胞骨架纤维丝排列方向随机,取向角为(45.5±3.7)°,各取向角内骨架纤维数量分布均匀,但60μm、100μm、140μm的水凝胶微凹槽中的细胞骨架蛋白纤维取向角显著降低,分别为(14.4±3.1)°、(24.7±3.5)°、(31.9±3.3)°,不同宽度水凝胶微凹槽中取向角<30°的骨架纤维数量明显增加(P<0.001),但随着水凝胶微凹槽宽度增加,取向角<30°的骨架纤维数量逐渐减少,而取向角60°~90°的骨架纤维数量逐渐增加(P<0.001)。结论水凝胶微凹槽可调控HUVECs形态与取向,在一定程度上可模拟血管内皮细胞的在体微环境,为研究血管内皮细胞的独特生理功能提供了更符合生理条件的实验模型,但三维空间约束影响血管内皮细胞形态和组装的分子机制有待进一步研究。

关键词：微图案血管内皮细胞细胞形态细胞取向细胞骨架

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提取温度对乌鱼鱼鳞明胶功能性质和结构特性的影响

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食品工业科技 2024年第9期45卷 83-90页

作者：黄丽金闻怡凡罗美玲乔娟娟蒋文丽谢欢舒圣方婷涂宗财沙小梅江西师范大学生命科学学院国家淡水鱼加工技术研发专业中心江西南昌330022 希而思(长沙)科技研究院有限公司湖南长沙410000 南昌大学食品科学与资源挖掘全国重点实验室江西南昌330047 江西德上医药研究院有限公司江西樟树331208

功能性质是衡量鱼明胶品质的重要因素,直接关系着鱼明胶的实际应用范围和价值。为探究提取温度对乌鱼鱼鳞明胶功能性质的影响,本研究以乌鱼鱼鳞为原料,采用热水法提取明胶,考察了不同温度(60、70、80、90、100℃)提取对鱼鳞表面形态、... 详细信息

功能性质是衡量鱼明胶品质的重要因素,直接关系着鱼明胶的实际应用范围和价值。为探究提取温度对乌鱼鱼鳞明胶功能性质的影响,本研究以乌鱼鱼鳞为原料,采用热水法提取明胶,考察了不同温度(60、70、80、90、100℃)提取对鱼鳞表面形态、鱼鳞明胶得率、功能性质(起泡性、乳化性、凝胶强度、凝胶温度、胶融温度)的影响,并进一步通过SDS-PAGE、傅里叶变换红外光谱、扫描电镜探究鱼鳞明胶的结构特性。结果表明:当提取温度从60℃逐步升高到100℃,乌鱼鱼鳞表面的破损越来越严重,鱼鳞明胶得率从31.72%增加到50.97%,起泡能力从23.33%提升至73.33%,乳化活性从15.13 m^(2)/g增长到17.27 m^(2)/g,而凝胶强度、凝胶温度、胶融温度则从677.82 g、20.80℃、28.70℃分别降低至372.91 g、15.80℃、23.90℃。此外,随着提取温度的提升,电泳图中乌鱼鱼鳞明胶α_(1)、α_(2)、β链三条特征带逐渐模糊,红外光谱结果表明鱼鳞明胶都具有特征吸收峰(酰胺A、酰胺Ⅰ、酰胺Ⅱ、酰胺Ⅲ)且酰胺A带波数先升高后降低,扫描电镜结果显示鱼鳞明胶多孔网格结构的紧密程度降低。上述研究结果可为乌鱼鱼鳞明胶产业化提供理论依据。

关键词：乌鱼鱼鳞明胶提取温度功能性质结构特性

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Wetting alternating with partial drying during grain filling increases lysine biosynthesis in inferior rice grain

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The Crop Journal 2024年第1期12卷 262-270页

作者： Yi jiang wenli Tao Weiyang Zhang Zhiqin Wang Jianchang Yang jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009JiangsuChina

Lysine content is a criterion of the nutritional quality of *** the process of lysine biosynthesis in early-flowering superior grain(SG)and late-flowering inferior grain(IG)of rice would advance breeding and cultivation to improve nutritional ***,little information is available on differences in lysine anabolism between SG and IG and the underlying mechanism,and whether and how irrigation regimes affect lysine anabolism in these grains.A japonica rice cultivar was grown in the field and two irrigation regimes,continuous flooding(CF)and wetting alternating with partial drying(WAPD),were imposed from heading to the mature *** content and activities of key enzymes of lysine biosynthesis,and levels of brassinosteroids(BRs)were lower in the IG than in the SG at the early grainfilling stage but higher at middle and late grain-filling *** increased activities of these key enzymes,BR levels,and contents of lysine and total amino acids in IG,but not SG relative to *** of 2,4-epibrassinolide to rice panicles in CF during early grain filling reproduced the effects of WAPD,but neither treatment altered the activities of enzymes responsible for lysine catabolism in either SG or *** and elevated BR levels during grain filling increased lysine biosynthesis in *** in lysine biosynthesis in rice should focus on IG.

关键词： Brassinosteroids Inferior grain Lysine biosynthesis Rice Wetting alternating with partial drying

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Fast approximate maximum likelihood period estimation from incomplete timing data

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Chinese Journal of Aeronautics 2013年第2期26卷 435-441页

作者： Ye Haohuan Liu Zheng jiang wenli College of Electronic Science & Engineering National University of Defense Technology

To estimate the period of a periodic point process from noisy and incomplete observations, the classical periodogram algorithm is modified. The original periodogram algorithm yields an estimate by performing grid search of the peak of a spectrum, which is equivalent to the periodogram of the periodic point process, thus its performance is found to be sensitive to the chosen grid spacing. This paper derives a novel grid spacing formula, after finding a lower bound of the width of the spectral mainlobe. By employing this formula, the proposed new estimator can determine an appropriate grid spacing adaptively, and is able to yield approximate maximum likelihood estimate （MLE） with a computational complexity of O（n2）. Experimental results prove that the proposed estimator can achieve better trade-off between statistical accuracy and complexity, as compared to existing methods. Simulations also show that the derived grid spacing formula is also applicable to other estimators that operate similarly by grid search.

关键词： Grid search Maximum likelihood period estimation Periodic point process Periodogram Pulse repetition frequency

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A Linear-correction Least-squares Approach for Geolocation Using FDOA Measurements Only

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Chinese Journal of Aeronautics 2012年第5期25卷 709-714页

作者： LI Jinzhou GUO Fucheng jiang wenli School of Electronic Science and Engineering National University of Defense TechnologyChangsha 410073China

A linear-correction least-squares（LCLS） estimation procedure is proposed for geolocation using frequency difference of arrival （FDOA） measurements only. We first analyze the measurements of FDOA, and further derive the Cramer-Rao lower bound （CRLB） of geoloeation using FDOA measurements. For the localization model is a nonlinear least squares（LS） estimator with a nonlinear constrained, a linearizing method is used to convert the model to a linear least squares estimator with a nonlinear con- strained. The Gauss-Newton iteration method is developed to conquer the source localization problem. From the analysis of solving Lagrange multiplier, the algorithm is a generalization of linear-correction least squares estimation procedure under the condition of geolocation using FDOA measurements only. The algorithm is compared with common least squares estimation. Comparisons of their estimation accuracy and the CRLB are made, and the proposed method attains the CRLB. Simulation re- sults are included to corroborate the theoretical development.

关键词： signal processing frequency difference of arrival Cramer-Rao lower bound linear-correction least-squares Gauss-Newton iteration method Lagrange multiplier

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Inhibitory effect of procyanidin B2 and tannin acid on cholesterol esterase and their synergistic effect with orlistat

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Food Science and Human Wellness 2024年第1期13卷 360-369页

作者： Xiangxin Li Yijing Pu Haitao jiang Wenxiao Jiao Wenjun Peng wenli Tian Weibo jiang Xiaoming Fang Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China College of Food Science and Nutritional Engineering China Agricultural UniversityBeijing 100083China College of Food Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

This study was aimed to analyze the effect of procyanidin B2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic *** interaction mechanisms were investigated by enzymatic kinetics,multi-spectroscopy methods,thermodynamics analysis,molecular docking,and dynamic *** and TA could bind with CEase and inhibit the activity of enzyme in a mixed-competitive manner and non-competitive manner,which was verified by molecular docking simulations and dynamics ***,PC and TA showed the synergistic inhibition with ***,UVvis and the thermodynamic analysis revealed that the complexes were formed from CEase and inhibitors by noncovalent *** revealed by the circular dichroism results,both PC and TA decreased enzymatic activities by altering the conformations of *** inhibition of PC and TA on CEase might be one mechanism for its cholesterol-lowering effect.

关键词： Cholesterol esterase Polyphenols Interaction mechanisms Molecular dynamic simulation Synergistic effect

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Anisodine hydrobromide alleviates oxidative stress caused by hypoxia/reoxygenation in human cerebral microvascular endothelial cells predominantly via inhibition of muscarinic acetylcholine receptor 4

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BIOCELL 2023年第10期47卷 2255-2263页

作者： wenli jiang JUNYI SHEN XIAOQIANG DU YAN QIU JIAN ZHONG ZHI OUYANG BINGMEI M.FU YE ZENG Institute of Biomedical Engineering West China School of Basic Medical Sciences&Forensic MedicineSichuan UniversityChengdu610041China Department of Biomedical Engineering The City College of the City University of New YorkNew York10031USA

Background:Anisodine hydrobromide(AT3),an anti-cholinergic agent,could be delivered to the brain across the blood-brain barrier and has been used clinically for the treatment of cerebral ischemia/reperfusion *** dysfunction can be caused by hypoxia/reoxygenation(H/R)via oxidative stress and metabolic *** present study investigated whether AT3 regulates the production of nitric oxide(NO)and reactive oxygen species(ROS),and the HIF-1αpathway via regulation of muscarinic acetylcholine receptors(mAChRs)in brain microvascular endothelial cells after H/R ***:Under H/R conditions,hCMEC/D3 cerebral microvascular endothelial cells were treated with *** inhibitors of M2-and M4-mAChRs were used to explore the mechanism by which AT3 influences oxidative stress in endothelial ***,mAChRs expression was detected by western blotting and NO production was detected by Greiss *** intracellular ROS level was measured using DCFH-DA *** expression of hypoxia-inducible transcription factor 1α(HIF-1α)was also ***:While H/R induced the expression of M2-and M4-mAChRs,AT3 suppressed the H/R-upregulated M2-and M4-mAChRs.H/R also induced the production of NO,ROS,and ***3 and M4-mAChR inhibitors inhibited the H/R-induced production of NO and ROS and ***-1αwas induced by H/R,but was suppressed by ***:Thus,the in vitro evidence shows that AT3 protects against H/R injury in cerebral microvascular endothelial cells via inhibition of HIF-1α,NO and ROS,predominantly through the downregulation of *** findings offer novel understandings regarding AT3-mediated attenuation of endothelial cell apoptosis and cerebral ischemia/reperfusion injury.

关键词： Hypoxia/reoxygenation Endothelial cell Anisodine hydrobromide Muscarinic acetylcholine receptors Hypoxia-inducible factor-1α

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基于多种癌症的生物信息学分析探究转酮醇酶在耐药中的作用

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生命的化学 2024年第6期44卷 1098-1116页

作者：李松卢占英姜文丽徐尧杨延龙焦炳华卢小玲海军军医大学生物化学与分子生物学教研室上海200433 海军军医大学基础医学院实验教学中心上海200433 海军军医大学第一附属医院中医外科上海200433 海军军医大学中医系上海200433

癌症是目前中国和发达国家主要的死亡原因。随着癌症基因组测序技术的进步与成熟,对癌症相关基因有了更深入的了解,为寻找新的治疗靶点提供了新的可能性。通过生物信息学的研究,结果发现,转酮醇酶(transketolase,TKT)在泛癌的发生和进... 详细信息

癌症是目前中国和发达国家主要的死亡原因。随着癌症基因组测序技术的进步与成熟,对癌症相关基因有了更深入的了解,为寻找新的治疗靶点提供了新的可能性。通过生物信息学的研究,结果发现,转酮醇酶(transketolase,TKT)在泛癌的发生和进展中扮演着关键角色,涉及肿瘤分期和不良预后。大量的数据分析和文献研究揭示了TKT在肿瘤发生中的异常修饰现象,并发现TKT与多种顺铂耐药基因有关。我们对未来充满期待,相信会有更多的TKT抑制剂先导化合物出现,为癌症治疗带来新的希望。

关键词：转酮醇酶泛癌分析 DNA甲基化磷酸化耐药

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Biochemistry and transcriptome analysis reveal condensed tannins alleviate liver injury induced by regulating cholesterol metabolism pathway

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Food Science and Human Wellness 2024年第2期13卷 909-919页

作者： Xiangxin Li Yijing Pu Bangdi Liu Xiaoming Fang Wenjun Peng Weibo jiang wenli Tian Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China College of Food Science and Nutritional Engineering China Agricultural UniversityBeijing 100083China Academy of Agricultural Planning and Engineering Ministry of Agriculture and Rural AffairsBeijing 100125China

Free cholesterol has been considered to be a critical risk factor of nonalcoholic fatty liver disease(NAFLD).It remains unknown whether dietary intake of condensed tannins(CTs)have distinguishable effects to alleviate liver damage caused by a high cholesterol *** C57BL/6 mice were fed a high cholesterol diet for 6 weeks,and given CTs treatment at a dosage of 200 mg/(kg·day)at the same *** results indicated that compared with mice fed a normal diet,a high cholesterol diet group resulted in significant weight loss,dysregulation of lipid metabolism in blood and liver,and oxidative stress in the liver,but CTs treatment dramatically reversed these negative *** and eosin(H&E)staining and frozen section observation manifested that CTs treatment could effectively reduce the deposition of liver cholesterol and tissue necrosis caused by high cholesterol *** alleviated liver injury mainly by regulating the expression of related genes in cholesterol metabolism pathway and AMPK *** results confirmed that CTs have remarkable cholesterol lowering and anti-liver injury effects in vivo.

关键词： Condensed tannins High cholesterol Liver injury Antioxidants Transcriptomic analysis

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