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High Technology Letters 2008年第1期14卷 104-111页

作者：朱新平 Zhou Li chen Yongle Du Hejun gui Jianfang State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Wuhan 430072 P.R. China Pearl River Fisheries Research Institute Chinese Academy of Fishery Sciences Guangzhou 510380 P.R. China

Mauremys mutica(Cantor,1842)is an endangered species in *** phenotypic variations inbody color,body weight,body shape,clutch size,egg size,and hatchling size were revealed betweenthe southern and northern *** populations have the phenomenon of'larger male'sexualsize dimorphism(SSD),especially in the southern ***,genetic variations betweenthe two populations were analyzed by RAPD band patterns of 30 random individuals in each *** average genetic distance was 0.299±0.108 among the samples of two *** average ge-netic distance between southern and northern populations was 0.305±*** analysis indicatedthat all the individuals from the southern and northern populations were clustered among themselves toform two distinct clades.A total of 20 population-specific RAPD fragments were scored from 16 primers,and could be used as RAPD markers for distinguishing the southern and the northern *** the nucleotide sequences of two RAPD markers,two pairs of SCAR primers(SC1-S and SC2-S)weredesigned,which could be used as SCAR markers for the southern *** to the significantphenotypic and genetic variations,we suggested that the northern population and southern populationmight be considered as two separate taxa,the'northern taxon'and the'southern taxon',and the con-servation should be respectively conducted on the two taxa.

关键词： Mauremys mutica (Cantor 1842) phenotypic variation RAPD SCAR marker genetic heterogeneity

A comparative study of proliferation and osteogenic differentiation of rat adipose-derived stem cells in β-tricalcium phosphate (β-TCP), forsterite (Mg_2SiO_4 ) and clinoenstatite (MgSiO_3)

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Chinese Science Bulletin 2013年第24期58卷 3033-3042页

作者： LENG Bin jin XiaoGang LIN QiuXia chen Lei WANG Yan DU ZhiYan LIN KaiLi CHANG Jiang GU XiaoMing WANG ChangYong Department of Implantology of People's Armed Police General Hospital Department of Advanced Interdisciplinary Studies Institute of Basic Medical Sciences and Tissue Engineering Research Center Academy of Military Medical Sciences State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences

In this study, the effects of forsterite and clinoenstatite powder extracts on the proliferation and osteogenic differentiation of rat adipose-derived stem cells (ASCs) were investigated and compared with the β-tricalcium phosphate (β-TCP) powder extracts. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay and live-dead staining were performed to evaluate the viability and proliferation of rat ASCs. Osteogenic differentiation of rat ASCs were assayed by alkaline phosphatase (ALP) staining and ALP activity test. The expression of osteogenic marker genes (alkaline phosphatase (ALP), runt related transcription factor 2 (Runx2), collagen type Iα1 (Col1α1), secreted phosphoprotein1 (Spp1, osteopontin), integrin binding sialoprotein (Ibsp), bone gla protein (Bglap)) were detected by real-time polymerase chain reaction (PCR). The MTT assay and the live-dead staining showed that all the three ceramics possessed good cytocompatibility with rat ASCs. Furthermore, forsterite and clinoenstatite promoted the proliferation of rat ASCs compared with β-TCP. The results of the ALP activity test and the real-time PCR demonstrated that forsterite and clinoenstatite promoted the osteogenic differentiation of rat ASCs. These results suggested that forsterite and clinoenstatite are bioactive ceramics that may be used for preparation of bone tissue engineering (BTE) scaffolds.

关键词：脂肪干细胞成骨分化细胞增殖镁橄榄石 TCP相磷酸三钙 Mg2SiO4 MgSiO3

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基于人工智能的断层自动识别研究进展

地球物理学进展 2021年第1期36卷 119-131页

作者：陈桂刘洋中国石油大学(北京)油气资源与探测国家重点实验室北京102249 中国石油大学(北京)克拉玛依校区克拉玛依834000 中国石油大学(北京)CNPC物探重点实验室北京102249

随着油气勘探开发工作的进行,构造圈闭的勘探难度不断提高,断层作为油气运移、聚集的主要通道之一,断层的识别精度很大程度上影响了油气藏的勘探开发.在断层识别的发展过程中,国内外学者们提出了许多切实可行的方案.近年来,人工智能领... 详细信息

随着油气勘探开发工作的进行,构造圈闭的勘探难度不断提高,断层作为油气运移、聚集的主要通道之一,断层的识别精度很大程度上影响了油气藏的勘探开发.在断层识别的发展过程中,国内外学者们提出了许多切实可行的方案.近年来,人工智能领域的兴起,使得断层自动识别方法更加多样化.本文通过调研大量的国内外相关文献,对基于人工智能的断层自动识别方法进行了归纳总结,将其划分为两个大类:智能算法、机器学习,又对每个大类进行了精细划分,并阐述了通过蚁群算法、边缘检测、BP神经网络、支持向量机、生成对抗网络、聚类及卷积神经网络来自动识别断层的基本原理、发展现状及优缺点.此外,卷积神经网络拥有卷积层、池化层等特殊结构,可以直接通过学习输入与输出之间的映射关系来实现断层自动识别,具有很好的非线性表达及泛化能力,相较于其他人工智能方法,兼具了较高的效率与精度.因此本文对基于卷积神经网络来自动识别断层的一些关键技术及优化算法进行了重点介绍,且利用大量三维合成地震记录及断层标签作为训练样本,实现了基于卷积神经网络的三维地震资料断层自动识别并对最终结果进行了深入分析.最后对断层自动识别技术的提高,给出展望与相应的结论.

关键词：断层自动识别人工智能智能算法机器学习卷积神经网络

基于偏最小二乘法的三种光谱定量测定LDPE/PP共混物组分含量的比较研究

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光谱学与光谱分析 2015年第8期35卷 2147-2153页

作者：陈如黄晋刚华南理工大学聚合物新型成型装备国家工程研究中心聚合物成型加工工程教育部重点实验室广东广州510641

分别利用中红外(mid-infrared,MIR)、近红外(near-infrared,NIR)和拉曼光谱(Raman)采集了31种不同比例的低密度聚乙烯/聚丙烯(LDPE/PP)共混物样本的光谱,利用偏最小二乘法(partial least-square,PLS)建立了光谱数据与LDPE含量的模型,研究了不同光谱范围和预处理方法对模型准确性的影响,并比较了三种光谱定量测量的准确性。结果表明,对于光谱差异小、存在噪音或基线干扰的谱图,预处理方法和光谱范围对模型的准确性均有较大的影响;经过三种预处理以及选择合适的光谱范围建立的模型决定系数(R2)分别从未处理前的0.887 6,0.849 3和0.875 7提升到0.990 6,0.997 3和0.997 2,校正均方根误差(root mean square error of calibration,RMSEC)则分别从10.15,11.75和10.67降低到2.941,1.561和1.598;三种光谱在经过预处理之后均能够较好地定量测量LDPE的含量,NIR和Raman模型准确性更高,由于两者的测量速度快,因此尤其适合于进行快速、准确的定量测量。

关键词：中红外近红外拉曼预处理方法光谱范围定量准确性

Photonic cavity enhanced high-performance surface plasmon resonance biosensor

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Photonics Research 2020年第4期8卷 448-456页

作者： gui-SHI LIU XIN XIONG SHIQI HU WEIchenG SHI YAOFEI chen WENGUO ZHU HUADAN ZHENG JIANHUI YU NUR HIDAYAH AZEMAN YUNHAN LUO ZHE chen Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Jinan UniversityGuangzhou 510632China Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Education Institutes Jinan UniversityGuangzhou 510632China Key Laboratory of Visible Light Communications of Guangzhou Jinan UniversityGuangzhou 510632China Photonics Technology Laboratory Centre of Advanced Electronic and Communication EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia

Herein we propose a novel strategy to enhance surface plasmon resonance(SPR)by introducing a photonic cavity into a total-internal-reflection *** photonic cavity,which is comprised of a highly reflective photonic crystal(PC),defect layers,and a gold(Au)film,enables Fabry–Perot(FP)resonances in the defect layers and therefore narrows the SPR resonance width in the metallic surface as well as increases the electric field intensity and penetration depth in the evanescent *** fabricated sensor exhibits a 5.7-fold increase in the figure of merit and a higher linear coefficient as compared with the conventional Au-SPR *** demonstrated PC/FP cavity/metal structure presents a new design philosophy for SPR performance enhancement.

关键词： Photonic cavity enhanced high-performance surface plasmon resonance biosensor

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重构X射线脉冲星信号的纯数值模拟新算法

国防科技大学学报 2015年第2期37卷 143-148页

作者：桂先洲黄森林孙晨国防科技大学航天科学与工程学院湖南长沙410073

基于X射线脉冲星的导航技术,无论技术研究还是实验验证,都是以X射线脉冲星信号为基础。但是实际的观测数据无法确定其精确值,不便于进行导航算法的分析验证。因此,通过模拟算法重构X射线脉冲星信号十分必要。基于泊松分布建立X射线脉冲... 详细信息

基于X射线脉冲星的导航技术,无论技术研究还是实验验证,都是以X射线脉冲星信号为基础。但是实际的观测数据无法确定其精确值,不便于进行导航算法的分析验证。因此,通过模拟算法重构X射线脉冲星信号十分必要。基于泊松分布建立X射线脉冲星信号模型,介绍脉冲轮廓的构建方法;介绍了两种纯数值的脉冲星信号模拟算法。针对这两种算法因近似导致信号模拟不精确的问题,提出一种基于精确光子流量函数的纯数值X射线脉冲星信号的模拟算法,该算法采用分段线性函数拟合的脉冲轮廓函数,基于分布函数及其反函数导出。模拟算法重构PSR B0531+21脉冲星的信号,并利用χ2拟合优度检验验证模拟算法生成的光子到达时间服从泊松分布。将提出的算法与两种已有的算法进行比较,仿真结果表明从光子数目和脉冲轮廓误差来看,提出的算法都优于其他两种算法,更接近实际信号。由新算法重构的脉冲星信号进行历元折叠得到观测脉冲轮廓,并将其与标准脉冲轮廓比较,发现随着观测时间的增长,观测脉冲轮廓趋近于标准脉冲轮廓,验证了模拟算法是有效可行的。

关键词： X射线脉冲星泊松分布信号重构卡方拟合优度检验模拟算法

Nano-hydroxyapatite accelerates vascular calcification via lysosome impairment and autophagy dysfunction in smooth muscle cells

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Bioactive Materials 2022年第2期7卷 478-493页

作者： Qi Liu Yi Luo Yun Zhao Pingping Xiang jinyun Zhu Wangwei jing Wenjing jin Mingyao chen Ruikang Tang Hong Yu Department of Cardiology Cardiovascular Key Laboratory of Zhejiang ProvinceThe Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang Province310009China The Affiliated Cardiovascular Hospital of Qingdao University QingdaoShandong Province266071China Department of Chemistry Zhejiang UniversityHangzhouZhejiang Province310027China

Vascular calcification(VC)is a common characteristic of aging,diabetes,chronic renal failure,and *** basic component of VC is hydroxyapatite(HAp).Nano-sized HAp(nHAp)has been identified to play an essential role in the development of pathological calcification of ***,whether nHAp can induce calcification in vivo and the mechanism of nHAp in the progression of VC remains *** discovered that nHAp existed both in vascular smooth muscle cells(VSMCs)and their extracellular matrix(ECM)in the calcified arteries from *** nHAp had similar morphological and chemical properties as natural nHAp recovered from calcified *** stimulated osteogenic differentiation and accelerated mineralization of VSMCs in *** nHAp could also directly induce VC in ***,nHAp was internalized into lysosome,which impaired lysosome vacuolar H+-ATPase for its acidification,therefore blocked autophagic flux in *** re-acidification by cyclic-3′,5′-adenosine monophosphate(cAMP)significantly enhanced autophagic degradation and attenuated nHAp-induced *** accumulated autophagosomes and autolysosomes were converted into calcium-containing exosomes which were secreted into ECM and accelerated vascular calcium *** of exosome release in VSMCs decreased calcium ***,our results demonstrated a repressive effect of nHAp on lysosomal acidification,which inhibited autophagic degradation and promoted a conversion of the accumulated autophagic vacuoles into exosomes that were loaded with undissolved nHAp,Ca^(2+),Pi and *** exosomes bud off the plasma membrane,deposit within ECM,and form calcium *** calcification was thus accelerated by nHAP through blockage of autophagic flux in VSMCs.

关键词： Nano-hydroxyapatite Vascular calcification Autophagy Lysosome Exosome

Congenital duodenal obstruction in neonates:a decade's experience from one center

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World Journal of Pediatrics 2014年第3期10卷 238-244页

作者： Qing-Jiang chen Zhi-Gang Gao jin-Fa Tou Yun-Zhong Qian Min-Ju Li Qi-Xing Xiong Qiang Shu Department of Pediatric General Surgery Children's HospitalZhejiang University Shool of MedicineHangzhou 310003China Department of Pediatric Thoracic Surgery Children's HospitalZhejiang University Shool of MedicineHangzhou 310003China

Background:Congenital duodenal obstruction(CDO)is one of the most common anomalies in newborns,and accounting for nearly half of all cases of neonatal intestinal *** study aimed to review our single-center experience in managing congenital duodenal obstruction while evaluate the ***:We conducted a retrospective analysis of the records of all neonates dianogsed with congenital duodenal obstruction admitted to our center between January 2003 and December *** analyzed demographic criteria,clinical manifestations,associated anomalies,radiologic findings,surgical methods,postoperative complications,and fi nal ***:The study comprised 287 newborns(193 boys and 94 girls).Birth weight ranged from 950 g to 4850 ***-three patients were born prematurely between 28 and 36 weeks'*** was diagnosed in 174 patients,annular pancreas in 66,duodenal web in 55,duodenal atresia or stenosis in 9,preduodenal portal vein in 2,and congenital band compression in *** patients had various combinations of these *** symptoms included bilious vomiting,dehydration,and weight loss.X-rays of the upper abdomen demonstrated the presence of a typical double-bubble sign or air-fluid levels in 68.64%of patients,and confi rmatory upper and/or lower gastrointestinal contrast studies were obtained in 64.11%.Multiple associated abnormalities were observed in 50.52%of the *** surgical approaches were used,including Ladd's procedure,duodenoplasty,duodenoduodenostomy,duodenojejunostomy,or a combination of *** patients died postoperatively and 14 required ***:Congenital duodenal obstruction is a complex entity with various etiologies and often includes multiple concomitant *** diagnosis and aggressive surgery are key to improving *** should be taken to address all of the causes of duodenal obstruction and/or associated alimentary tract anomalies during surge

关键词： congenital duodenal obstruction neonate

Surgical instruments hyalinization:Occlusion removal in minimally invasive endoscopic surgery

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Biomimetic Intelligence & Robotics 2023年第3期3卷 1-8页

作者： Dongsheng Xie Wenxin chen jin Zhao Xinya Song Kaifeng Wang Weiwei Xia Haiying Liu Fangle Chang Changsheng Li Xingguang Duan School of Medical Technology Beijing Institute of TechnologyBeijing 100081China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Spinal Surgery Peking University People’s HospitalBeijing 100044China Ningbo Innovation Center Zhejiang UniversityNingBo 315100China

Minimal invasion is an important trend in ***,the endoscope,as one of the key devices for monitoring the process of minimally invasive surgery,is limited by its size and working space it operates in,which result in a considerably narrow field of *** particular,when a surgical instrument enters through the tool channel,the instrument occupies most of the area in an endoscopic *** hampers the surgeon’s field of view and has a negative impact on the *** study proposes a novel method for removing the occlusion caused by surgical instruments in endoscopic images by making foreground occlusions on endoscopic images transparent using image restoration and interframe information *** with unprocessed images,this method can provide a clearer field of view that is necessary for minimally invasive endoscopic surgeries and improve the quality of *** endoscopic images are used to verify the feasibility of the proposed method,and the results show that the proposed method improves the visual effect of endoscopic images by removing surgical-instrument *** demonstrates the considerable potential of the proposed method for use in clinical applications.

关键词： Image inpainting Minimally invasive endoscopic surgery Occlusion removal

Ferromagnetism at 230 K in(Ba_(0.7)K_(0.3))(Zn_(0.85)Mn_(0.15))_2As_2 diluted magnetic semiconductor

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Chinese Science Bulletin 2014年第21期59卷 2524-2527页

作者： Kan Zhao Bijuan chen Guoqiang Zhao Zhen Yuan Qingqing Liu Zheng Deng jinlong Zhu Changqing jin Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of Sciences

We report the ferromagnetism with Cure temperature Tcat 230 K in a new diluted magnetic semiconductor(DMS)(Ba0.7K0.3)(Zn0.85Mn0.15)2As2isostructural to ferropnictide 122 superconductors synthesized via low temperature *** is doped by isovalence substitution of Mn2+for Zn2+,while charge is introduced by heterovalence substitution of K1+for Ba2+in(Ba0.7K0.3)(Zn0.85Mn0.15)2As2DMS,being different from(Ga,Mn)As where both spin&charge are induced simultaneously by heterovalence substation of Mn2+for Ga3+.The(Ba0.7K0.3)(Zn0.85Mn0.15)2As2DMS shows spontaneous magnetization following T3/2dependence expected for a homogeneous ferromagnet with saturation moment 1.0μB for each Mn atom.

关键词：稀磁半导体铁磁性 DMS ZnO 固化温度烧结合成自发磁化饱和磁矩