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HDR到LDR图像的分段式对数映射算法

计算机应用 2008年第7期28卷 1724-1725,1741页

作者：谭锐莘中国科学技术大学计算机科学技术系合肥230027

为了适应低端显示设备输出,需要一定的方法将高动态范围(HDR)图像转换为相应的低动态范围(LDR)图像。如果既考虑到人眼对亮度反应呈对数变化又利用图像自身的亮度分布,对高动态范围图像进行先全局后局部的映射,便得到一种分段式对数映... 详细信息

为了适应低端显示设备输出,需要一定的方法将高动态范围(HDR)图像转换为相应的低动态范围(LDR)图像。如果既考虑到人眼对亮度反应呈对数变化又利用图像自身的亮度分布,对高动态范围图像进行先全局后局部的映射,便得到一种分段式对数映射算法。该算法的复杂度较低,在视觉效果上结合了对数映射和分段映射算法的特点。

关键词：高动态范围图像低动态范围图像调和映射

Study on alantolactone-induced differentiation of mesenchymal stem cells intovascular cells

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Traditional Medicine Research 2018年第4期3卷 181-190页

作者： Yan-Jiao Lu Qiong Lu Ruo-Ke Su GangWang rui tan School of Life Sciences and Engineering Southwest Jiaotong University Chengdu China National EngineeringResearch Center for Biomaterials Sichuan University Chengdu China College of Medicine Southwest JiaotongUniversity Chengdu China

To promote efficient screening of active angiogenic drugs from traditional medicines, we constructed a humanembryonic kidney-293 cell model using vascular endothelial growth factor （VEGF） gene promoter as the drug target. Inthis model, VEGF gene promoter may regulate the expression of the luciferase reporter gene by responding to thestimulation of drug molecules. This cell model allows rapid and efficient screening of vascular-inducing activecomponents from several drug monomer molecules. Furthermore, we used rat bone marrow mesenchymal stem cells（rMSCs） to conduct a preliminary study on the activity of alantolactone. Using simvastatin as a positive control, weinvestigated the effects of alantolactone on the expression of vascular-related cell marker molecules such as VEGF andα-smooth muscle actin （α-SMA） in rMSCs. According to our results, 0.1, 1, 3 and 5 μM of alantolactone upregulated thetranscriptional luciferase gene activity of VEGF promoter, and a significant difference from that in the control group wasobserved. Among them, 3μM of alantolactone showed the better effect than that of 3 μM of simvastatin （P = 0.036） andother concentrations of alantolactone and simvastatin showed similar effects. Compared with that in the control group,rMSCs induced with 1μM alantolactone for 3 days showed a significant increase in the relative mRNA expressions ofVEGF and α-SMA genes. However, these effect of 5 μM alantolactone were weaker than those of 5 μM simvastatin （P 〈0.05）; rMSCs treated with 1 μM alantolactone for 3 days showed brighter green fluorescence （FITC marker） of α-SMAand VEGF in situ expression than that observed in the control group and similar fluorescence intensity than that ofsimvastatin group in an immunoradiometric assay. The above results demonstrate the reliability of the highly efficientsystem for screening of active drug molecules and confirmed the vascular induction function of alantolactone at the geneand protein levels.

关键词： Alanlactone Angiogenesis Stably transformed cell line rMSCs VEGF α-SMA

Evidence of fluid evolution of Baoshan Cu−Pb−Zn polymetallic deposit:Constraints from in-situ sulfur isotope and trace element compositions of pyrite

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Transactions of Nonferrous Metals Society of China 2021年第11期31卷 3530-3548页

作者： Jun-ke ZHANG Yong-jun SHAO Ke CHEN Hua-jie tan rui-chang tan Tian-dong ZHANG Zhong-fa LIU Key Laboratory of Metallogenic Prediction of Nonferrous Metals Ministry of EducationCentral South UniversityChangsha 410083China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China

In-situ LA-ICP-MS and S isotopes of pyrite from the Baoshan Cu polymetallic deposit were conducted to investigate the ore-forming process and the enrichment mechanism of *** generations of pyrite (Py Ⅰ,Py Ⅱ,and Py Ⅲ) in the skarn-type ores and pyrite in the carbonate-hosted sulfide ores from central,western,and northern(C_Py,W_Py,and N_Py) mining districts are selected for *** with Py Ⅰ and Py Ⅲ,the contents of most elements in Py Ⅱ are apparently *** As and Se contents are high within a wide range and are decoupled in the growth band of the C_*** highest As,Se,and Pb contents were found in W_Py and N_*** results indicate the drastic changes in the temperature and fluid mixing during the *** occurrence of fluctuation and change in temperature and f(O_(2)) was triggered by intermittent pulses of magmatic-hydrothermal fluids,mixing with meteoric water,and water-rock *** sulfur isotopes of all species of pyrite indicated the magmatic *** change in the f(O_(2)) conditions caused slight differences in the sulfur isotope ***,a metallogenic model was proposed to explain the ore-forming processes.

关键词： pyrite trace element in-situ S isotope hydraulic fracturing fluid mixing

Performance investigation of a low-power Hall thruster fed on iodine propellant

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Plasma Science and Technology 2024年第6期26卷 140-148页

作者：徐宗琦王平阳蔡东升谭睿姜文静 Institute of Engineering Thermophysics School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

The common propellants used for electric thrusters, such as xenon and krypton, are rare, expensive,and difficult to acquire. Solid iodine attracts much attention with the advantages of low cost,extensive availability, low vapor pressure, and ionization potential. The performance of a lowpower iodine-fed Hall thruster matched with a xenon-fed cathode is investigated across a broad range of operation conditions. Regulation of the iodine vapor's mass flow rates is stably achieved by using a temperature control method of the iodine reservoir. The thrust measurements are finished utilizing a thrust target during the tests. Results show that thrust and anode-specific impulse increase approximately linearly with the increasing iodine mass flow *** the nominal power of 200 W class, iodine mass flow rates are 0.62 and 0.93 mg/s, thrusts are7.19 and 7.58 m N, anode specific impulses are 1184 and 826 s, anode efficiencies are 20.8%and 14.5%, and thrust to power ratios are 35.9 and 37.9 m N/k W under the conditions of 250 V,0.8 A and 200 V, 1.0 A, respectively. The operating characteristics of iodine-fed Hall thruster are analyzed in different states. Further work on the measurements of plasma characteristics and experimental optimization will be carried out.

关键词： electric propulsion Hall thruster iodine propellant thrust measurement operating characteristics

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父母表露与青少年人际能力的关系研究

心理发展与教育 2008年第2期24卷 60-64页

作者：谭锐周晖中山大学心理学系广州510275

本研究考察父母表露内容、动机及模式对他们孩子的同伴间人际能力的影响。68对亲子,共204人参加了本次研究,父母平均年龄44岁,青少年平均年龄17岁。青少年匿名填写《青少年人际能力问卷》,父母则各自填写《自我表露量表》和《表露话题... 详细信息

本研究考察父母表露内容、动机及模式对他们孩子的同伴间人际能力的影响。68对亲子,共204人参加了本次研究,父母平均年龄44岁,青少年平均年龄17岁。青少年匿名填写《青少年人际能力问卷》,父母则各自填写《自我表露量表》和《表露话题与动机量表》。结果发现:(1)父母在表露话题、动机、模式上存在差异;(2)青少年的人际能力能够被父母表露话题、动机及模式预测,但父母变量对各能力的解释量有所不同;(3)青少年表达不满、情绪支持能力由父母表露变量共同预测,而发起交往、自我表露、冲突管理能力则由父亲表露变量单独预测。

关键词：自我表露亲子沟通人际能力

CARBONIUM CYCLIZATION—STUDIES ON LIGNANS CONTAINING THE DIBENZOCYCLOOCTADIENE SYSTEM.Ⅰ

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Chinese Chemical Letters 1990年第1期1卷 47-48页

作者： rui tan Qi Tai ZHENG Cun Heng HE Xiao Tian LIANG Institute of Materia Medica,Nan-wei Road,Beijing 100050

Schisandrin(1)under the Ritter reaction conditions (conc.H_2SO_4/CH_3CN)gave trace amounts of the expected acetamido derivatives(2a,2b).The main product is 5a,from intramolecular car- bonium cyclization.

关键词： STUDIES ON LIGNANS CONTAINING THE DIBENZOCYCLOOCTADIENE SYSTEM CARBONIUM CYCLIZATION

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小邻域方法对数据的分类

数学的实践与认识 2018年第10期48卷 97-105页

作者：谭瑞梅郑州轻工业学院数学与信息科学学院

为了由数据特征实施对数据更好的查询、图像更好的分割，提出了一种小邻域分类（ε—NC）方法．ε—NC能找出最佳的分类数量，分类时间明显减少．引入相对熵损失来限制样本图像的失真，采用可变步长搜索方法提高最小采样率搜索过程的效... 详细信息

为了由数据特征实施对数据更好的查询、图像更好的分割，提出了一种小邻域分类（ε—NC）方法．ε—NC能找出最佳的分类数量，分类时间明显减少．引入相对熵损失来限制样本图像的失真，采用可变步长搜索方法提高最小采样率搜索过程的效率；给出模糊隶属度，形成分类的有效性判断函数，减少迭代次数．采用ε—NC分类方法，对图像分割的准确率高、速度快、抗噪能力强，它对图像目标分类的准确率比传统最好的分类方法的准确率平均提高了5．65％，搜索速度提高9—12倍．

关键词：小邻域分类(ε-NC) 阈值熵模糊有效性判断函数模糊隶属度

碰撞能及反应物振动激发对Ar+H_2^+→ArH^++H反应立体动力学性质的影响

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物理学报 2014年第2期63卷 140-145页

作者：胡梅刘新国谭瑞山山东师范大学物理与电子科学学院济南250014

基于我们最近所构建的Ar+H+2→ArH++H(12A′)反应的新势能面,采用准经典轨线法研究了碰撞能分别为0.48,0.77,1.24 eV以及能量为0.48 eV时反应物不同振动态下Ar+H+2→ArH++H反应的立体动力学性质.结果显示在给定的碰撞能情况下,以及当反... 详细信息

基于我们最近所构建的Ar+H+2→ArH++H(12A′)反应的新势能面,采用准经典轨线法研究了碰撞能分别为0.48,0.77,1.24 eV以及能量为0.48 eV时反应物不同振动态下Ar+H+2→ArH++H反应的立体动力学性质.结果显示在给定的碰撞能情况下,以及当反应物振动量子数由0变到2时计算的积分反应截面与实验值符合得较好.通过比较发现,碰撞能对此反应k-j′关联函数P(θr)分布的影响大于其受振动激发的影响,并且关于k-k′-j′三矢量相关的函数P(?r)分布以及极化微分反应截面对碰撞能较敏感,同时发现振动激发对P(?r)分布和极化微分反应截面也有较大的影响.

关键词：准经典轨线法积分反应截面矢量相关极化微分反应截面

Regulatory variation within 3’UTR of STAT5A correlates with sudden cardiac death in Chinese populations

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Forensic Sciences Research 2022年第4期7卷 726-735页

作者： Huan Yu Yadong Guo Zhenzhen Yang Qing Zhang Jiabin Xu Qi Yang Yiling Qu rui tan Lijuan Li Yan He Chengtao Li Suhua Zhang Bin Luo Yuzhen Gao Department of Forensic Medicine Medical College of Soochow UniversitySuzhouChina Department of Forensic Science School of Basic Medical SciencesCentral South UniversityChangshaChina Public Security Bureau of Taixing TaizhouChina Department of Epidemiology Medical College of Soochow UniversitySuzhouChina Shanghai Key Laboratory of Forensic Medicine Academy of Forensic ScienceShanghaiChina Faculty of Forensic Medicine Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouChina

Definitive diagnosis to sudden cardiac death(SCD)is often challenging since the postmortem examination on SCD victims could hardly demonstrate an adequate cause of *** is therefore important to uncover the inherited risk component to *** transducer and activators of transcription 5 A(STAT5A)is a member of the STAT family and a transcription factor that is activated by many cell ligands and associated with various cardiovascular *** this study,we performed a systematic variant screening on the STAT5A to filter potential functional genetic *** on the screening results,an insertion/deletion polymorphism(rs3833144)in 3’UTR of STAT5A was selected as the candidate variant.A total of 159 SCD cases and 668 SCD matched healthy controls was enrolled to perform a case-control study and evaluate the association between rs3833144 and SCD susceptibility in Chinese *** regression analysis showed that the deletion allele of rs3833144 had significantly increased the SCD risk(odds ratio(OR)=1.54;95%confidence interval(CI)=1.18-2.01;P=0.000955).Further genotype-expression eQTL analysis showed that samples with deletion allele appeared to lower expression of STAT5A,and in silico prediction suggested the local 3 D structure changes of STAT5A mRNA caused by the *** the other hand,the bioinformatic analysis presented that promoters of RARA and PTGES3L-AARSD1 could interact with rs3833144,and eQTL analysis showed the higher expression of both genes in samples with deletion ***-luciferase activity assays also suggested the significant regulatory role of rs3833144 in gene *** current data thus suggested a possible involvement of rs3833144 to SCD predisposition in Chinese populations and rs3833144 with potential function roles may become a candidate marker for SCD diagnosis and prevention.

关键词： Forensic sciences forensic genetics STAT5A 3’UTR rs3833144 sudden cardiac death indel polymorphism