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Automatic Alzheimer’s Disease Recognition from MRI Data Using Deep Learning Method

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Journal of Applied Mathematics and Physics 2017年第9期5卷 1892-1898页

作者： Suhuai Luo xuechen li Jiaming li School of Electrical Engineering and Computing The University of Newcastle Callaghan Australia School of Computer Science Shenzhen University Shenzhen China Quantitative Imaging Research Team CSIRO Data61 Marsfield Australia

Alzheimer’s Disease (AD), the most common form of dementia, is an incurable neurological condition that results in a progressive mental deterioration. Although definitive diagnosis of AD is difficult, in practice, AD diagnosis is largely based on clinical history and neuropsychological data including magnetic resource imaging (MRI). Increasing research has been reported on applying machine learning to AD recognition in recent years. This paper presents our latest contribution to the advance. It describes an automatic AD recognition algorithm that is based on deep learning on 3D brain MRI. The algorithm uses a convolutional neural network (CNN) to fulfil AD recognition. It is unique in that the three dimensional topology of brain is considered as a whole in AD recognition, resulting in an accurate recognition. The CNN used in this study consists of three consecutive groups of processing layers, two fully connected layers and a classification layer. In the structure, every one of the three groups is made up of three layers, including a convolutional layer, a pooling layer and a normalization layer. The algorithm was trained and tested using the MRI data from Alzheimer’s Disease Neuroimaging Initiative. The data used include the MRI scanning of about 47 AD patients and 34 normal controls. The experiment had shown that the proposed algorithm delivered a high AD recognition accuracy with a sensitivity of 1 and a specificity of 0.93.

关键词： Alzheimer’s Disease AD Recognition Magnetic Resource Imaging MRI Deep Learning Convolutional Neural Network CNN

Improvement of liver Segmentation by Combining High Order Statistical Texture Features with Anatomical Structural Features

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Engineering（科研） 2013年第5期5卷 67-72页

作者： Suhuai Luo xuechen li Jiaming li The CSIRO ICT Centre Australia The University of Newcastle Australia

Automatic segmentation of liver in medical images is challenging on the aspects of accuracy, automation and robustness. A crucial stage of the liver segmentation is the selection of the image features for the segmentation. This paper presents an accurate liver segmentation algorithm. The approach starts with a texture analysis which results in an optimal set of texture features including high order statistical texture features and anatomical structural features. Then, it creates liver distribution image by classifying the original image pixelwisely using support vector machines. Lastly, it uses a group of morphological operations to locate the liver organ accurately in the image. The novelty of the approach is resided in the fact that the features are so selected that both local and global texture distributions are considered, which is important in liver organ segmentation where neighbouring tissues and organs have similar greyscale distributions. Experiment results of liver segmentation on CT images using the proposed method are presented with performance validation and discussion.

关键词： liver Segmentation Texture Feature Support Vector machine Morphological Operation

Review on the Methods of Automatic liver Segmentation from Abdominal Images

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Journal of Computer and Communications 2014年第2期2卷 1-7页

作者： Suhuai Luo xuechen li Jiaming li The CSIRO Computational Informatics Australia The University of Newcastle Australia

Automatic liver segmentation from abdominal images is challenging on the aspects of segmentation accuracy, automation and robustness. There exist many methods of liver segmentation and ways of categorisingthem. In this paper, we present a new way of summarizing the latest achievements in automatic liver segmentation. We categorise a segmentation method according to the image feature it works on, therefore better summarising the performance of each category and leading to finding an optimal solution for a particular segmentation task. All the methods of liver segmentation are categorized into three main classes including gray level based method, structure based method and texture based method. In each class, the latest advance is reviewed with summary comments on the advantages and drawbacks of each discussed approach. Performance comparisons among the classes are given along with the remarks on the problems existed and possible solutions. In conclusion, we point out that liver segmentation is still an open issue and the tendency is that multiple methods will be employed together to achieve better segmentation performance.

关键词： liver Segmentation Image Feature Performance Comparison Review Survey

Chemical Biology Studies on Bacterial Pseudaminic Acid

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Chemical Biology Studies on Bacterial Pseudaminic Acid

Argon plume transition from a hollow swell to a diffuse swell with increasing amplitude of a trapezoidal voltage

中国化学会第三届全国糖化学会议

作者： xuechen li Department of Chemistry The University of Hong Kong

Pseudaminic acid(Pse),first discovered in 1984,has been identified in a variety of pathogenic bacteria as important surface *** to the nonulosonic acid carbohydrate family,Pse is structurally related to its well-known congener,sialic ***,Pse exists with both α and β configuration in native glycoconjugates with variable substitution patterns at N5 and *** structural diversity makes the structure-function relationship of Pse-containing glycans both intriguing but also *** biological and evolutional significances of bacterial pseudaminic acid and its glycoconjugates remain largely unexplored,due to the lack of synthetic access to pseudaminic acid and the structurally-defined pseudaminylated *** 2017,we developed a facile and scalable de novo synthesis of pseudaminic acid(16 steps in11%). Furthermore,we developed a robust methodology for the "perfect" stereocontrolled chemical glycosidation of pseudaminic acid to afford both(only) α-and(only) β-*** was achieved through the use of a common glycosyl donor(5 N-azide)/7 NCbz Pse thioglycoside)through the simple modulation of the reaction *** power of the methodology is highlighted through the stereocontrolled preparation of a large number of α-and β-pseudaminylated substrates encompassing a variety of biologically-relevant *** of such bimodal selectivity,representing the ‘ideal’ situation,are both sparse and highly sought-after in carbohydrate chemistry,with most donors requiring implementation of directing groups or extensive optimization of protecting groups to achieve a single stereochemical outcome(*** donors for different linkages).This bimodal selectivity is particularly advantageous for the study of pseudaminic acid,not only because it naturally occurs with both α and β linkage types,but also because at present it can only be derived through lengthy chemical synthesis,providing very little material to devote to sta

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Plasma Science and Technology 2022年第8期24卷 84-90页

作者： Junyu CHEN Furong ZHANG Pengying JIA Na ZHAO Kaiyue WU Jiacun WU Junxia RAN Xuexia PANG xuechen li College of Physics Science&Technology Hebei UniversityBaoding 071002People's Republic of China Institute of life Science&Green Development Hebei UniversityBaoding 071002People's Republic of China School of Mathematics and Physics Handan UniversityHandan 056005People's Republic of China

Atmospheric pressure plasma jets can generate a remote plasma plume,which usually presents a conical or cylindrical *** a few morphologies being observed,efforts should be made to obtain more plume structures because streamer dynamics may be revealed from *** this purpose,an argon plasma plume excited by a trapezoidal voltage is investigated,which presents two kinds of swells(a hollow swell and a diffuse swell)with increasing voltage amplitude(V).The results indicate that there are two positive discharges(Dand D)and one negative discharge(D)per voltage cycle for both of the *** increasing V,the inception voltage and discharge intensity increase for every positive discharge,while they decrease for the negative *** photography reveals that the positive streamer(D)leaves different tracks in the two swells,which are curved in the hollow swell and randomly branched in the diffuse *** different tracks of Dare explained with the consideration of applied field strength and residual positive ions of *** existence of residual positive ions is finally verified from optical emission spectra.

关键词： plasma jet plume morphology streamer behavior optical emission spectra

Influence of oxygen addition on the discharge characteristics of an argon plasma jet at atmospheric pressure

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Chinese Physics B 2022年第6期31卷 535-540页

作者： Junyu Chen Na Zhao Jiacun Wu Kaiyue Wu Furong Zhang Junxia Ran Pengying Jia Xuexia Pang and xuechen li College of Physics Science&Technology Hebei UniversityBaoding 071002China School of Mathematics and Physics Handan UniversityHandan 056005China Institute of life Science&Green Development Hebei UniversityBaoding 071002China

Plasma jet is an important low-temperature plasma source in extensive application *** promote the production of active oxygen species,oxygen is often introduced into the inert working ***,the influence of oxygen content on the discharge characteristics of an argon plasma jet is not *** to this status,an argon plasma jet in a singleelectrode geometry is employed to investigate the influence of oxygen concentration(CO)on discharge *** indicate that with increasing CO(≤0.6%),the plume transits from a diffuse morphology to a hollow *** and optical measurements reveal that both discharge number per voltage cycle and pulse intensity alter with varying ***,discharge morphologies of negative and positive discharges obtained by fast photograph also shift with varying ***,optical emission spectra are collected to investigate atomic CO,electron density,and electron *** results mentioned above are explained qualitatively,which are believed to be of great significance for the applications of atmospheric pressure plasma jet.

关键词： plasma jet oxygen addition fast photography optical emission spectra

Influence of bias voltage and oxygen addition on the discharge aspects of a diffuse argon plume in an atmospheric pressure plasma jet

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Plasma Science and Technology 2024年第12期26卷 75-81页

作者： Pengying JIA Guoxin HAN Xiupin DONG Kaiyue WU Junxia RAN Xuexia PANG Xuexue ZHANG Jiacun WU xuechen li College of Physics Science and Technology Hebei UniversityBaoding 071002People’s Republic of China Engineering Research Center of Zero-carbon Energy Buildings and Measurement Techniques Ministry of EducationBaoding 071002People’s Republic of China Department of Electrical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Hebei Key Laboratory of Photo-Electricity Information and Materials Hebei UniversityBaoding 071002People’s Republic of China

A remote plasma,also referred to as a plasma plume(diffuse or filamentary),is normally formed downstream of an atmospheric pressure plasma *** this study,a diffuse plume is formed by increasing the bias voltage(U_(b))applied to the downstream electrode of an argon plasma jet excited by a negatively pulsed *** results indicate that the plume is filamentary when U_(b)is low,which transits to the diffuse plume with increasing U_(b).The discharge initiated at the rising edge of the pulsed voltage is attributed to the diffuse plume,while that at the falling edge contributes to the filament in the *** the diffuse plume,the discharge intensity decreases with the increasing oxygen content(C_o).Fast photography reveals that the diffuse plume results from a negative streamer,which has a dark region near the nozzle with C_o=0%.However,the dark region is absent with C_o=0.5%.From the optical emission spectrum,the electron density,electron excitation temperature,gas temperature,and oxygen atom concentration are investigated.

关键词： atmospheric pressure plasma jet diffuse plasma plume optical emission spectrum

Recent advances in chemical protein synthesis:method developments and biological applications

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Science China Chemistry 2024年第4期67卷 1060-1096页

作者： Suwei Dong Ji-Shen Zheng Yiming li Huan Wang Gong Chen Yongxiang Chen Gemin Fang Jun Guo Chunmao He Honggang Hu xuechen li Yanmei li Zigang li Man Pan Shan Tang Changlin Tian Ping Wang Bian Wu Chuanliu Wu Junfeng Zhao Lei liu State Key Laboratory of Natural and Biomimetic Drugs and School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Division of life Sciences and Medicine University of Science and Technology of ChinaHefei 230027China School of Food and Biological Engineering Engineering Research Center of Bio-processMinistry of EducationHefei University of TechnologyHefei 230009China School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210023China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China Department of Chemistry Tsinghua UniversityBeijing 100084China Institute of Health Sciences Anhui UniversityHefei 230601China College of Chemistry Central China Normal UniversityWuhan 430079China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China School of Medicine or Institute of Translational Medicine Shanghai UniversityShanghai 200444China Department of Chemistry The University of Hong KongHong Kong 999077China Shenzhen Graduate School Peking UniversityShenzhen 518055China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of life Sciences University of Science and Technology of ChinaHefei 230026China Department of Chemical Biology Shanghai Jiao Tong UniversityShanghai 200240China Institute of Microbiology Chinese Academy of SciencesBeijing 100101China Department of Chemistry Xiamen UniversityXiamen 361005China School of Pharmaceutical Science Guangzhou Medical UniversityGuangzhou 511436China

The central dogma of modern biology underscores the pivotal roles proteins play in diverse biological processes,the study of which necessitates advanced methods to produce proteins with precision and *** protein synthesis,a powerful approach utilizing chemical reactions for the de novo construction of structurally accurate proteins,has emerged as a transformative tool for studying proteins and generating protein derivatives/mimics inaccessible by natural biological machinery,including post-translationally modified proteins,proteins comprised of unnatural amino acids,as well as mirror-image *** review summarizes recent strides in synthetic method developments for chemical protein synthesis,including innovative techniques in solid-phase peptide synthesis,the challenges presented by difficult sequences in either synthesis or folding and the exploration of novel ligation reactions using both chemical and enzymatic ***,the review also delves into newly developed protocols for site-selective protein modifications and the generation of stapled or macrocyclized peptides/miniproteins,highlighting the power of chemical methods to make structurally diverse *** applications of synthetic proteins in investigating post-translational modifications(phosphorylation,lipidation,glycosylation,ubiquitination,etc.),mirror-image biological processes and drug development are further ***,these topics provide a comprehensive overview of the current landscape of chemical protein synthesis.

关键词： chemical protein synthesis solid-phase peptide synthesis ligation reactions post-translational modifications mirror-image proteins peptide drugs

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离心叶轮出口流动分离区影响因素的数值研究

西安交通大学学报 2013年第9期47卷 16-22页

作者：李学臣席光西安交通大学能源与动力工程学院西安710049

针对离心叶轮出口区域的流动分离问题,对影响离心叶轮出口流动分离的3种因素进行了数值研究。研究离心叶轮扩压度影响时发现:对于闭式叶轮,叶轮扩压度对出口的流动影响较大,当叶轮的进口与出口相对速度比大于2时,设计工况下叶轮出口出... 详细信息

针对离心叶轮出口区域的流动分离问题,对影响离心叶轮出口流动分离的3种因素进行了数值研究。研究离心叶轮扩压度影响时发现:对于闭式叶轮,叶轮扩压度对出口的流动影响较大,当叶轮的进口与出口相对速度比大于2时,设计工况下叶轮出口出现了较大的流动分离区,这与传统的设计理论一致;对于半开式叶轮,设计工况下叶轮出口均出现了流动分离,且分离区的大小随着叶轮扩压度的增加而增大。研究叶顶间隙对离心叶轮出口流动分离影响时发现:叶顶间隙对叶轮出口流动分离区的大小影响显著,就所研究的叶轮而言,并非间隙越小分离区越小,当叶顶间隙为7.5%叶轮出口宽度时,叶轮出口流动分离区最小。研究叶片扩压器进口收敛角对半开式叶轮出口流动分离区的影响时发现,增大扩压器进口收敛角可以有效抑制叶轮出口的流动分离,但是收敛角过大,叶轮叶顶间隙区域附近的叶尖回流区增大,整级的气动性能降低。

关键词：离心叶轮出口流动分离扩压度收敛角