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DNA Damage,Apoptosis and C-myc,C-fos,and C-jun Overexpression Induced by Selenium in Rat Hepatocytes

Biomedical and Environmental Sciences 2006年第3期19卷 197-204页

作者： ri-AN yu cheng-FENG YANG XUE-MIN CHEN Department of Occupational and Environmental Health MOE Key Laboratory of Environment and Health School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China

Objective To study the effects of selenium on DNA damage, apoptosis and c-myc, c-fos, and c-jun expression in rat hepatocytes. Methods Sodium selenite at the doses of 5, 10, and 20 μmol/kg was given to rats by i.p. and there were 5 male SD rats in each group. Hepatocellular DNA damage was detected by single cell gel electrophoresis （or comet assay）. Hepatocellular apoptosis was determined by TUNEL （TdT-mediated dUTP nick end labelling） and flow cytometry. C-myc, c-fos, and c-jun expression in rat bepatocytes were assayed by Northern dot hybridization. C-myc, c-fos, and c-jun protein were detected by immunohistochemical method. Results At the doses of 5, 10, and 20μmol/kg, DNA damage was induced by sodium selenite in rat hepatocytes and the rates of comet cells were 34.40%, 74.80%, and 91.40% respectively. Results also showed an obvious dose-response relationship between the rates of comet cells and the doses of sodium selenite （r=0.9501, P〈0.01）. Sodium selenite at the doses of 5, 10, and 20μmol/kg caused c-myc, c-fos, and c-jun overexpression obviously. The positive brown-yellow signal for proteins of c-myc, c-fos, and c-jun was mainly located in the cytoplasm of bepatocytes with immunohistocbemical method. TUNEL-positive cells were detected in selenium-treated rat livers. Apoptotic rates （%） of selenium-treated liver cells at the doses of 5, 10, and 20 μmol/kg were （3.72±1.76）, （5.82±1.42）, and （11.76±1.87） respectively, being much higher than those in the control. Besides an obvious dose-response relationship between apoptotic rates and the doses of sodium selenite （r=0.9897, P〈0.01）, these results displayed a close relationship between DNA damage rates and apoptotic rates, and the relative coefficient was 0.9021, P〈0.01. Conclusion Selenium at 5-20μmol/kg can induce DNA damage, apoptosis, and overexpression of c-myc, c-fos, and c-jun in rat hepatocytes.

关键词： Selenium DNA damage Apoptosis C-myc C-fos C-jun

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Pressure Effects on the Magnetic Phase Transition of Mn_(3)SnC_(1−x)N_(x)(x=0,0.5)

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Chinese Physics Letters 2012年第8期29卷 191-193页

作者： HU Jing-yu WEN Yong-Chun YAO yuan WANG Cong ZHAO Qing JIN Chang-Qing yu ri-cheng Physical College Beijing Institute of TechnologyBeijing 100081 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesP.O.Box 603Beijing 100190 Center for Condensed Matter and Materials Physics Beihang UniversityBeijing 100191

The electronic transport properties of Mn_(3)SnC and Mn_(3)SnC_(0.5)N_(0.5) were measured under pressures up to 1.8 *** ambient pressure,an abrupt increase of resistance occurs around the temperature of magnetic phase transition in both *** transition temperature TC from paramagnetic to ferrimagnetic state decreases linearly at rates of 12.6 and 6.3 K/GPa with pressure for Mn_(3)SnC and Mn_(3)SnC_(0.5)N_(0.5),*** phenomenon could be understood by the Labbe–Jardin tight binding approximation model.

关键词： resistance Transition transition

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Ultrasonic Properties of the MgB_(2) Superconductor

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Chinese Physics Letters 2001年第10期18卷 1369-1370页

作者： LI Shao-Chun WANG Ru-Ju LI Feng-Ying LIU Zhen-Xing ZHU Jia-Lin yu ri-cheng JIN Chang-Qing Laboratory for Extreme Condition Physics Institute of Physicsand Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080 Beijing Center for High Pressure Research Chinese Academy of SciencesBeijing 100080

The sound velocities of longitudinal and shear waves are measured on a polycrystalline MgB_(2) superconductor with Tc of 39 K. The specimen used in the experiments is pressed and heated using the MgB_(2) powder. The elastic moduli, Debye temperature and specific heat at room temperature are obtained based on sound velocity data. The results indicate that the velocities are much higher than those in the usual materials, while elastic constants remain reasonably soft, which may be due to the high transition temperature of the MgB2 superconductor.

关键词： heated Superconductor superconductor

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羟苯磺酸钙胶囊联合全视网膜光凝术对糖尿病视网膜病变患者视力状况、眼底微循环及脉络膜厚度的影响

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现代生物医学进展 2024年第13期24卷 2582-2586,2572页

作者：丁桂玲李莉李坤鹏余日成林月嫦李彩云张雪玲广州中医药大学东莞医院(东莞市中医院)眼科广东东莞523000 东莞市光明眼科医院眼科广东东莞523000

目的:探讨羟苯磺酸钙胶囊联合全视网膜光凝术(PRP)对糖尿病视网膜病变(DR)患者视力状况、眼底微循环及脉络膜厚度的影响,以期为DR患者提供合理治疗方案。方法:选取2022年8月-2023年1月我院收治的的96例DR患者,按数字随机分组法分为试验... 详细信息

目的:探讨羟苯磺酸钙胶囊联合全视网膜光凝术(PRP)对糖尿病视网膜病变(DR)患者视力状况、眼底微循环及脉络膜厚度的影响,以期为DR患者提供合理治疗方案。方法:选取2022年8月-2023年1月我院收治的的96例DR患者,按数字随机分组法分为试验组和对照组各48例,对照组采用PRP治疗,试验组采用羟苯磺酸钙胶囊联合PRP治疗,持续治疗4周。对比两组治疗总有效率和黄斑中心凹厚度(CMT)、最佳矫正视力(BCVA)、眼压水平以及眼底微循环[阻力指数(ri)、收缩期峰值平均流速(PSV)、舒张末期平均血流速度(EDV)]、脉络膜厚度[黄斑中心凹脉络膜厚度(SFCT)、上方脉络膜厚度(SCT)、下方脉络膜厚度(ICT)、颞侧脉络膜厚度(TCT)、鼻侧脉络膜厚度(NCT)]及并发症情况。结果:试验组治疗4周后的总有效率明显高于对照组(Pri水平较治疗前均显著改善,且试验组显著优于对照组(P0.05)。结论:羟苯磺酸钙胶囊联合PRP有利于提升DR患者的治疗总有效率,对改善患者视力状况、眼底微循环及脉络膜厚度具有积极作用,且安全性好,是临床治疗DR患者的合理有效的方案,为临床治疗DR提供了新的思路和方法。

关键词：羟苯磺酸钙胶囊 PRP 糖尿病视网膜病变视力状况视网膜血流密度脉络膜厚度

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Microstructure recognition of steels by machine learning based on visual attention mechanism

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Journal of Iron and Steel Research International 2024年第4期31卷 909-923页

作者： Xing-yu Chen Lin cheng cheng-yang Hu yu-peng Zhang Kai-ming Wu The State Key Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical ProcessingInternational Research Institute for Steel TechnologyCollaborative Center on Advanced SteelsWuhan University of Science and TechnologyWuhan 430081HubeiChina Metals Valley and Band(Foshan)Metallic Composite Materials Co. Ltd.Foshan 528000GuangdongChina

U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the *** representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction *** is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure *** reasons for the accuracy improvement were discussed based on the feature maps analysis.

关键词： Microstructure recognition-Steel Machine learning Visual attention mechanism Visualization

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Capillary Property of Entangled Porous Metallic Wire materials and Its Application in Fluid Buffers:Theoretical Analysis and Experimental Study

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Defence Technology（防务技术） 2024年第1期31卷 400-416页

作者： yu Tang Yiwan Wu Hu cheng Rong Liu Engineering Research Center for Metal Rubber School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350156China AECC Guizhou Liyang Aviation Power Co. LTDGuiyang 550014China College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou 350156China

Strong impact does serious harm to the military industries so it is necessary to choose reasonable cushioning material and design effective buffers to prevent the impact of *** on the capillary property entangled porous metallic wire materials(EPMWM),this paper designed a composite buffer which uses EPMWM and viscous fluid as cushioning materials under the low-speed impact of the recoil force device of weapon equipment(such as artillery,mortar,etc.).Combined with the capillary model,porosity,hydraulic diameter,maximum pore diameter and pore distribution were used to characterize the pore structure characteristics of *** calculation model of the damping force of the composite buffer was *** low-speed impact test of the composite buffer was *** parameters of the buffer under low-speed impact were identified according to the model,and the nonlinear model of damping force was *** test results show that the composite buffer with EPMWM and viscous fluid can absorb the impact energy from the recoil movement effectively,and provide a new method for the buffer design of weapon equipment(such as artillery,mortar,etc.).

关键词： Entangled porous metallic wire materials Capillary property Viscousfluid Low-speed impact Damping force

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Evolution of inner wall wrinkle defects in the sinking zone of a thick-walled steel tube during radial forging

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Advances in Manufacturing 2024年第2期12卷 396-408页

作者： yu-Zhao Yang cheng Xu Li-Xia Fan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

An axial wrinkle defect was observed in the inner wall of the sinking zone of a thick-wall steel tube processed by cold radial *** can evolve into *** present study focuses on the evolution of wrinkles and the effects of process parameters on them using a three-dimensional radial forging process finite element model,radial forging experiments,and surface morphology *** results indicated that the vertical section angle of the hammer die and the size of the tube blank significantly affect the evolution of *** height-to-width ratioλwas introduced to describe the morphology of *** had an approximately linear relationship with the radius reduction in the sinking *** was a linear correlation between the growth slope ofλand the axial to circumferential strain ratio|εr/εθ|,which can predict theλunder few process *** the 30SiMn2MoVA steel,at the junction of the forging and sinking zones,the threshold ofλof the wrinkle that can evolve into a fissure is approximately 1.123.

关键词： Radial forging Inner wall Wrinkle defects Evolution Sinking zone

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Recent advances in post-chiroptical manipulation of supramolecular aggregates assembled with molecular modules

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Science China Chemistry 2024年第9期67卷 2842-2863页

作者： Yanling Shen Wanhua Wu Zhipeng yu cheng Yang Key Laboratory of Green Chemistry&Technology of Ministry of Education College of Chemistry InstitutionSichuan UniversityChengdu 610064China

Recently,various supramolecular assembly systems have been identified where the pre-existing chiral supramolecular structure can be manipulated through environmental adjustments,such as temperature,solvent,and *** changes result in diverse microscopic morphologies during the assembly process and induce chiroptical variations,particularly in circular dichroism(CD)and circularly polarized luminescence(CPL)*** chiroptical properties serve as direct indicators of the chiral supramolecular structure and hold promise for applications in sensing,molecular recognition,asymmetric synthesis,and material *** review focuses on research published in the last five years,highlighting instances where assembled structures aggregated by small organic molecular modules demonstrate in-situ chiroptical changes through external condition *** categorizes and discusses different modes of regulation,aiming to offer insights and guidelines for exploring dynamic changes in assembly processes and designing in-situ adjustable structures of assembly modules.

关键词： supramolecular assemblies post-chiroptical manipulation in-situ structural changes

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Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： Peng-bo Liu Shu-sen cheng yu-qing Xue Xiao-man cheng Zhao Liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

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Facile synthesis of high-brightness green-emitting carbon dots with narrow bandwidth towards backlight display

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Chinese Chemical Letters 2024年第5期35卷 277-282页

作者： Rui cheng Tingting Zhang Xin Huang Jian yu State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

High-performance carbon dots(CDs)allowing the application in high-end display devices are highly desirable and usually limited by the absence of simple and easy synthesis *** this work,we exploited an easy-to-implement strategy for the one-step synthesis of green-emitting CDs(G-CDs)with superb optical *** G-CDs were synthesized using m-phenylenediamine(m-PD)as a single precursor,and the reaction reacted at 180℃for 12 h The resultant G-CDs exhibit high-purity and excitationindependent green fluorescence with the photoluminescence(PL)peak located at 516 nm,full width at half maximum(FWHM)of 46 nm,and PL quantum yield(QY)of∼80%under the 470nm excitation *** G-CDs and corresponding composite film prepared with polyvinyl butyral(G-CDs@PVB)exhibit good PL stability after undergoing long-time storage for one year and 360 h exposure under 460nm blue *** G-CDs@PVB film was used as color-conversion materials in green-emitting light-emitting diode(LED)application,exhibiting a Commission internationale de l’Eclairage(CIE)chromaticity coordinate of(0.21,0.44).The film was also used in CD-based liquid crystal display(CD-LCD)application,achieving a color gamut value of 85%.This work will offer a working basis for the synthesis of high-performance CDs as well as their application in displays.

关键词： Carbon dots One-step synthesis Narrow bandwidth High quantum yield Display

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