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Application of synchrotron source based DEI method in guinea pig cochleae imaging

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Progress in Natural Science:Materials International 2007年第1期17卷 59-67页

作者： YIN Hongxia, LIU Bo, GAO Xin, GAO Xiulai and LUO Shuqian ( College of biomedical engineering, capital university of medical sciences, {3. 100069, China Department of Anatomy, capital university of medical sciences, {3. 100069, China) College of biomedical engineering Capital University of Medical Sciences Beijing 100069 China Department of Anatomy Capital University of Medical Sciences Beijing 100069 China

Hard X-ray diffraction enhanced imaging (DEI), which is based on a synchrotron source and monochromator-analyzer-crystal system, is an effective method for imaging X-ray phase shift. Utilizing an analyzer crystal with high angular sensitivity of micro-radian, DEI can measure the transmitted, refracted and scattered X-rays when projecting onto a sample. It dramatically improves the contrast and spatial resolution of the resultant images. At the topography station of beijing Synchrotron Radiation Facilities (BSRF), we implemented DEI method in guinea pig cochleae imaging and acquired a series of DEI images. Based on these images, the apparent absorption and refraction images were calculated. The DEI images revealed the holistic spiral structures and inner details of guinea pig cochleae clearly, even including the structures at the cellular level, such as the static cilia of hairy cells and the limbus of Hansen cell. Due to the advantages of high contrast, high spatial resolution and distinct edge-enhanced effect, DEI method promises extensive applications in biology, medicine and clinic in the near future.

关键词： diffraction enhanced imaging hard X-ray imaging phase-contrast imaging cochlea micro-structure synchrotron source.

Spinal processing of bee venom-induced pain and hyperalgesia

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生理学报 2008年第5期60卷 645-652页

作者： Jun CHEN institute for biomedical sciences of Pain and institute for Functional Brain Disorders,Tangdu Hospital,the Fourth Military {4. university,Xi’an 71003.,China institute for biomedical sciences of Pain,capital {4. university,beijing 100069,China institute for biomedical sciences of Pain and institute for Functional Brain Disorders Tangdu Hospital the Fourth Military Medical University Xi'an 710038

Subcutaneous injection of bee venom causes long-term neural activation and hypersensitization in the dorsal horn of the spinal cord,which contributes to the development and maintenance of various pain-related *** unique behavioral 'phenotypes' of nociception and hypersensitivity identified in the rodent bee venom test are believed to reflect a complex pathological state of inflammatory pain and might be appropriate to the study of phenotype-based mechanisms of pain and *** this review,the spinal processing of the bee venom-induced different 'phenotypes' of pain and hyperalgesia will be *** accumulative electrophysiological,pharmacological,and behavioral data strongly suggest that different 'phenotypes' of pain and hyperalgesia are mediated by different spinal signaling *** the phenotype-based mechanisms of pain might be useful in development of novel therapeutic drugs against complex clinic pathological pain.

关键词：脊髓痛觉过敏蜂毒疼痛治疗方法

Studies on repairing of hemisected thoracic spinal cord of adult rats by using a chitosan tube filled with alginate fibers

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Progress in Natural Science:Materials International 2006年第10期16卷 1051-1055页

作者： LI Xiaoguang, YANG Zhaoyang and YANG Yi ( beijing Center for Neural Regeneration and Repairing, capital university of medical sciences, beijing 100054, China Department of Bio{3., beijing university of Aeronautics and Astronautics, beijing 100083. China National Center of biomedical Analysis, beijing 100850, China) [a]beijing Center for Neural Regeneration and Repairing Capital University of Medical Sciences Beijing China [b]Department of Bioengineering Beijing University of Aeronautics and Astronautics Beijing China [c]National Center of biomedical Analysis Beijing China

A chitosan tube filled with alginate fibers was implanted into the injured spinal cord of a rat for repairing the damaged tissue. Twelve months after the operation, the morphological observation demonstrated that this chitosan tube could induce regeneration of myelinated and non-myelinated axons and blood vessels. The Basso-Beattie-Bresnahan (BBB) behavioral evaluation confirmed that the implants played a key role in the long-term restoration of rats motor functions. It is a promising start in the treatment of the patients with the injury of the spinal cord.

关键词： spinal cord injury regeneration function recovery chitosan alginate behavioral evaluation.

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3. WANG Yong2, DU Xiaolong1, MEI Zengxia1, KONG Xianghe3. JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2, 4.1. State Key Laboratory for Surface Physics, institute of Physics, Chinese Academy of sciences, {3. 100080, China 2. Laboratory of Electron Microscopy, institute of Physics, Chinese Academy of sciences, {3. 100080, China 3. College of Physics and engineering, Qufu Normal university, Qufu 273.65, China 4. {3. university of Technology, {3. 100022, China 1. State Key Laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. College of Physics and engineering Qufu Normal University 273165 Qufu China 3. Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. beijing university of Technology 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 3. rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

A novel model-free approach for reconstruction of time-delayed gene regulatory networks

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中国科学：生命科学英文版 2006年第2期49卷 190-200页

作者： JIANG Wei1,2, LI Xia1,2,3.4. GUO Zheng1,2,3. LI Chuanxing1, WANG Lihong1 & RAO Shaoqi1,5 1. Department of Bioinformatics, Harbin medical university, Harbin 150086, China 2. Department of Computer Science, Harbin {3. of Technology, Harbin 150080, China 3. School of Life Science and Technology, Tongji university, Shanghai 200092, China {4., capital university of medical sciences, beijing 100054, China 5. Departments of Cardiovascular Medicine and Molecular Cardiology, Cleveland Clinic Foundation, Cleveland, Ohio 4.195, USA Department of Bioinformatics Harbin Medical University Harbin 150086 China Department of Computer Science Harbin Institute of Technology Harbin 150080 China School of Life Science Technology Tongji University Shanghai 200092 China biomedical engineering institute Capital University of Medical Sciences Beijing 100054 China Departments of Cardiovascular Medicine Molecular Cardiology Cleveland Clinic Foundation Cleveland Ohio 44195 USA

Reconstruction of genetic networks is one of the key scientific challenges in functional genomics. This paper describes a novel approach for addressing the regulatory dependencies be-tween genes whose activities can be delayed by multiple units of time. The aim of the proposed ap-proach termed TdGRN (time-delayed gene regulatory networking) is to reversely engineer the dy-namic mechanisms of gene regulations, which is realized by identifying the time-delayed gene regu-lations through supervised decision-tree analysis of the newly designed time-delayed gene expres-sion matrix, derived from the original time-series microarray data. A permutation technique is used to determine the statistical classification threshold of a tree, from which a gene regulatory rule(s) is ex-tracted. The proposed TdGRN is a model-free approach that attempts to learn the underlying regula-tory rules without relying on any model assumptions. Compared with model-based approaches, it has several significant advantages: it requires neither any arbitrary threshold for discretization of gene transcriptional values nor the definition of the number of regulators (k). We have applied this novel method to the publicly available data for budding yeast cell cycling. The numerical results demonstrate that most of the identified time-delayed gene regulations have current biological knowledge supports.

关键词： gene regulatory networks, time delayed, decision tree.

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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Chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , Chinese Academy of sciences , beijing 100101, China 2. institute of Geology , Chinese Academy of sciences , beijing 100029, China 3. institute of High Energy Physics , Chinese Academy of sciences , beijing 100817 , China 4. beijing university of Science and engineering , beijing 100083. China Corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China institute of Geology Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China beijing university of Science and engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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Science China Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2, WANG Jin3. WU Yishi1, YUAN Gu3. AI Xicheng1, WANG Li4.& ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, Chinese Academy of sciences, {3. 100080, China 2. School of Life Science and Technology, {3. institute of Technology, {3. 100081, China 3. College of Chemistry and Molecular engineering, Peking university, {3. 100080, China 4. Center for Condensed Matter Physics, institute of Physics, Chinese Academy of sciences, {3. 100080, China Correspondence should be addressed to Ai Xicheng and Zhang Jianping 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. School of Life Science and Technology Beijing Institute of Technology Beijing 100081 China 3. College of Chemistry and Molecular engineering Peking University Beijing 100080 China 4. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 3. ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma School of Computer Science and engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

Information extraction and CT reconstruction of liver images based on diffraction enhanced imaging

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Progress in Natural Science:Materials International 2009年第8期19卷 955-962页

作者： Chunhong Hua,b, Tao Zhao a, Lu Zhanga, Hui Lia, Xinyan Zhao c, Shuqian Luoa, a College of biomedical engineering, capital {3. {4., beijing 100069, China b National Laboratory of Pattern Recognition, institute of Automation, Chinese Academy of sciences, beijing 100080, China c Liver Research Center, beijing Friendship Hospital, capital {3. {4., beijing 100050, China [a]College of biomedical engineering Capital Medical University Beijing 100069 China [b]National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China [c]Liver Research Center Beijing Friendship Hospital Capital Medical University Beijing 100050 China

X-ray phase-contrast imaging (PCI) is a new emerging imaging technique that generates a high spatial resolution and high contrast of biological soft tissues compared to conventional radiography. Herein a biomedical application of diffraction enhanced imaging (DEI) is presented. As one of the PCI methods, DEI derives contrast from many different kinds of sample information, such as the sample’s X-ray absorption, refraction gradient and ultra-small-angle X-ray scattering (USAXS) properties, and the sample information is expressed by three parametric images. Combinedwith computed tomography (CT), DEI-CT can produce 3. volumetric images of the sample and can be used for investigating micro-structures of biomedical samples. Our DEI experiments for liver samples were implemented at the topography station of beijing Synchrotron Radiation Facility (BSRF). The results show that by using our provided information extraction method and DEI-CT reconstruction approach, the obtained parametric images clearly display the inner structures of liver tissues and the morphology of blood vessels. Furthermore, the reconstructed 3. view of the liver blood vessels exhibits the micro blood vessels whose minimum diameter is on the order of about tens of microns, much better than its conventional CT reconstruction at a millimeter resolution. In conclusion, both the information extraction method and DEI-CT have the potential for use in biomedical micro-structures analysis.

关键词： Diffraction enhanced imaging Computed tomography Information extraction X-ray Liver