乳腺组织的位相衬度成像

将位相衬度成像用于乳腺肿瘤的结构研究后,发现：正常乳腺组织的吸收图像的清晰度比较高,原因是正常乳腺组织比较致密,对于对x射线的吸收相对较强。而位相村度成像在分辨肿瘤组织内部结构方面的优势是比较明显的,能够清晰地显示出乳腺组织中的一些精细结构,并可以反映出正常组织、良性肿瘤组织和癌变组织结构的特异性。在位相衬度成像中,图像的衬度是与样品到探测器的距离有关的,在不同样品到探测器的距离下,位相衬度成像的分辨率是不同的。根据衬度传递函数（CTF）,可以估计出乳腺癌组织中的钙化尺度在30μm左右。     

X光透镜在同轴X光位相成像中的应用

介绍了同轴X光位相成像的基本原理,说明了位相成像与普通吸收成像的区别;初步研究了X光透镜在位相衬度成像中的应用,利用整体会聚X光透镜将大焦斑光源汇聚为微焦斑,从而使出射的X光满足位相衬度成像所需的空间相干条件,得到了较好的实验结果,为进一步研究X光透镜在该领域的应用打下了基础.     

用于三维超宽带乳腺肿瘤成像的最佳天线系统

在超宽带（UWB）乳腺肿瘤检测系统中,采用Debye-Z．雏色散模型对乳房建模可以很好地近似人体组织的电导率及介电常数通过在乳腺模型中分别加入3个不同频带的超宽带天线阵列,带宽涵盖4～12GHz,采用共焦成像算法和波束形成算法对使用不同天线的色散模型进行成像对比,确定出最优性能的天线．2种成像算法均能准确获得肿瘤位置图像,使用频带为4．0～7．5GHz的天线对色散模型进行波束形成成像时,成像图分辨率较高,干扰抑制最好,可以清晰地分辨距离肋骨层仅10mm、直径为5mm的肿瘤．     

基于X射线光栅相位衬度的鲫鱼无损成像研究

近年来,光栅相位衬度成像成为当前X射线成像学界的研究热点,因其与传统X光源的高度兼容性而被认为是未来临床医学无损诊断的关键技术.与现有X射线吸收衬度成像技术相比,相位衬度成像技术对软组织具有不可替代的分辨能力.基于几何投影的X射线光栅相位衬度成像技术,无损研究了本地鲫鱼的鱼体结构,利用福尔马林溶液处理样品,发现成像结果清楚地显示出鱼肠组织的结构.这是第一次利用X射线光栅相位衬度成像技术观察到鱼肠组织.     

不同波长X射线对衍射增强成像的影响

为了研究不同波长X射线对衍射增强成像的影响,我们利用北京同步辐射光源4W1A光束线引出的硬X射线对肿瘤组织进行成像的研究。结果显示：表观吸收图像的可见度比在摇摆曲线顶部记录的峰位图像的可见度高,说明利用计算机图像重建可以提高图像的可见度;尽管折射图像的可见度不是很好,但其图像的层次感（衬度）会有所增加,便于图像的辨别;X射线波长较大（X射线能量较低）时,各种图像的可见度均比较高,可见长波长X射线有利于衍射增强成像。     

非矩形探测器阵列在相向运动中的成像优势分析

针对一种非矩形Retina-like探测器进行建模与仿真,研究其相向运动过程的模型.在不同场景及不同模糊度条件下对Retina-like探测器及矩形探测器的图像进行质量评价,不同的评价参数均表明Retina-like探测器在相向运动过程中的成像质量优于矩形探测器,具有抗辐射状模糊的效果,在相向运动过程中有明显的优势,为探索高速相向运动成像过程中的非矩形探测器面阵设计提供帮助.     

乳腺 MR 图像的有效分割

乳腺核磁共振影像（ MR）的有效分割一直是医学影像分析领域的研究热点。针对目前人工解读图像信息的不足,提出一种自动化分割乳腺MR图像的方法,该方法结合传统FCM算法和最小距离分类器实现了感兴趣区域中不同位置、灰度值相似的样本点按距离分类。算法首先根据图像的灰度信息利用FCM算法实现聚类,其次自动提取感兴趣区域的聚类信息,并利用最小距离分类器对其按距离分类。实验结果表明,该算法对乳腺核磁共振影像的分割具有较高的准确性,提高了其组织划分的精度,且自动化程度比较高,为后续进行肿瘤区域的自动提取与识别奠定基础。     

基于偏振成像的乳腺癌病理切片检测方法

生物组织具有与其结构和功能相关的固有光学特性,偏振成像技术能够根据组织正常和恶性变化之间的微观结构差异,表现出不同的偏振特性,从而实现两者区分。本研究设计了一套采集组织背向散射光Mueller矩阵的自动成像系统,对两种常见的乳腺癌病理组织切片分别进行Mueller矩阵成像实验,并对所得到的Mueller矩阵图像数据采用Mueller矩阵分解方法,分别提取出样本Mueller矩阵中具有清晰物理意义的参数图像。实验结果表明,相应的Mueller矩阵分解参数图像可以区分癌变组织和非癌变组织。这为乳腺癌的快速病理诊断提供了一种新的思路。     

扫描电镜中扫描透射成像装置的研制及应用

使用扫描电镜自带的背散射电子探头(BSED)作透射散射电子探测器,设计了一套适合FEI Quanta 650FEG扫描电镜使用的扫描透射(STEM)成像装置,并制定了该STEM成像装置的操作说明。以埃洛石复合ZrO₂纳米颗粒为观察对象,对自制STEM成像装置的实用性进行了验证。结果表明：STEM像衬度与背散射电子探头到样品之间的距离相关,通过调整背散射电子探头与样品之间的距离,可以实现高角环形暗场像的采集,使ZrO₂纳米颗粒的亮度明显高于埃洛石;STEM像衬度与透射电镜采集的HAADF-STEM像一致,元素分布状态也与埃洛石和ZrO₂纳米颗粒对应,表明所研制的STEM成像装置具有较好的实用性。     

偏振成像的乳腺癌病理切片检测方法

生物组织具有与其结构和功能相关的固有光学特性,偏振成像技术能够根据组织正常和恶性变化之间的微观结构差异,表现出不同的偏振特性,从而实现两者区分。设计了一套采集组织背向散射光Mueller矩阵的自动成像系统,对两种常见的乳腺癌病理组织切片分别进行Mueller矩阵成像实验,并对所得到的Mueller矩阵图像数据采用Mueller矩阵分解方法,分别提取出样本Mueller矩阵中具有清晰物理意义的参数图像。实验结果表明,相应的Mueller矩阵分解参数图像可以区分癌变组织和非癌变组织。这为乳腺癌的快速病理诊断提供了一种新的思路。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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