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Regularized canonical correlation analysis with unlabeled data

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 504-511页

作者： Xi-chuan ZHOU Hai-bin shen Institute of VLSI Design Zhejiang University Hangzhou 310027 China

In standard canonical correlation analysis (CCA), the data from definite datasets are used to estimate their canonical correlation. In real applications, for example in bilingual text retrieval, it may have a great portion of data that we do not know which set it belongs to. This part of data is called unlabeled data, while the rest from definite datasets is called labeled data. We propose a novel method called regularized canonical correlation analysis (RCCA), which makes use of both labeled and unlabeled samples. Specifically, we learn to approximate canonical correlation as if all data were labeled. Then, we describe a generalization of RCCA for the multi-set situation. Experiments on four real world datasets, Yeast, Cloud, Iris, and Haberman, demonstrate that, by incorporating the unlabeled data points, the accuracy of correlation coefficients can be improved by over 30%.

关键词： Canonical correlation analysis (CCA) Regularization Unlabeled data Generalized canonical correlation analysis(GCCA)

Adhesion behavior of endothelial progenitor cells to endothelial cells in simple shear flow

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Acta Mechanica Sinica 2011年第6期27卷 1071-1080页

作者： Xiao-Bo Gong Yu-Qing Li Quan-Chao Gao bin-bin Cheng Bao-Rong shen Zhi-Qiang yan Zong-Lai Jiang Institute of Mechanobiology and Biomedical Engineering School of Life Sciences and Biotechnology Shanghai Jiao Tong University 200240 Shanghai China Department of Engineering Mechanics School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University 200240 Shanghai China

The adhesion of endothelial progenitor cells（EPCs） on endothelial cells（ECs） is one of the critical physiological processes for the regenesis of vascular vessels and the prevention of serious cardiovascular ***,the rolling and adhesion behavior of EPCs on ECs was studied numerically.A two-dimensional numerical model was developed based on the immersed boundary method for simulating the rolling and adhesion of cells in a channel *** binding force arising from the catch bond of a receptor and ligand pair was modeled with stochastic Monte Carlo method and Hookean spring *** effect of tumor necrosis factor alpha（TNF-α） on the expression of the number of adhesion molecules in ECs was analyzed experimentally.A flow chamber system with CCD camera was set up to observe the top view of the rolling of EPCs on the substrate cultivated with *** results prove that the adhesion of EPC on ECs is closely related to membrane stiff-ness of the cell and shear rate of the *** also suggests that the adhesion force between EPC and EC by P-selectin glycoprotein ligand-1 only is not strong enough to bond the cell onto vessel walls unless contributions of other catch bond are *** results demonstrate that TNF-α enhanced the expressions of VCAM,ICAM,P-selectin and E-selectin in ECs,which supports the numerical results that the rolling velocity of EPC on TNF-α treated EC substrate decreases obviously compared with its velocity on the untreated *** is found that because the adhesion is affected by both the rolling velocity and the deformability of the cell,an optimal stiffness of EPC may exist at a given shear rate of flow for achieving maximum adhesion rates.

关键词： Endothelial progenitor cell Endothelial cell Cell adhesion. Flow chamber. Immersed boundary method

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin bin Mingming Zhao Jun Liu Jianrong yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

High-performance proton exchange membrane fuel cell with ultra-low loading Pt on vertically aligned carbon nanotubes as integrated catalyst layer

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Journal of Energy Chemistry 2022年第8期31卷 497-506,I0013页

作者： Qing Hao Meng Chao Hao Bowen yan bin yang Jia Liu Pei Kang shen Zhi Qun Tian Collaborative Innovation Center of Sustainable Energy Materials School of Physical Science and TechnologyGuangxi UniversityGuangxi Key Laboratory of Electrochemical Energy MaterialsState Key Laboratory of Processing for Non-ferrous Metal and Featured MaterialsNanning 530004GuangxiChina

Reducing a Pt loading with improved power output and durability is essential to promote the large-scale application of proton exchange membrane fuel cells(PEMFCs).To achieve this goal,constructing optimized structure of catalyst layers with efficient mass transportation channels plays a vital ***,PEMFCs with order-structured cathodic electrodes were fabricated by depositing Pt nanoparticles by Ebeam onto vertically aligned carbon nanotubes(VACNTs)growth on Al foil via plasma-enhanced chemical vapor *** demonstrate that the proportion of hydrophilic Pt-deposited region along VACNTs and residual hydrophobic region of VANCTs without Pt strongly influences the cell performance,in particular at high current *** Pt nanoparticles deposit on the top depth of around 600 nm on VACNTs with a length of 4.6μm,the cell shows the highest performance,compared with others with various lengths of *** delivers a maximum power output of 1.61 W cm^(-2)(H_(2)/O_(2),150 k Pa)and 0.79 W cm^(-2)(H_(2)/Air,150 k Pa)at Pt loading of 50μg cm^(-2),exceeding most of previously reported PEMFCs with Pt loading of<100μg cm^(-2).Even though the Pt loading is down to 30μg cm^(-2)(1.36 W cm^(-2)),the performance is also better than 100μg cm^(-2)(1.24 W cm^(-2))of commercial Pt/C,and presents better *** excellent performance is critical attributed to the ordered hydrophobic region providing sufficient mass passages to facilitate the fast water drainage at high current *** work gives a new understanding for oxygen reduction reaction occurred in VACNTs-based ordered electrodes,demonstrating the most possibility to achieve a substantial reduction in Pt loading<100μg cm^(-2) without sacrificing in performance.

关键词： Proton exchange membrane fuel cells Order-structured catalyst layer Vertically aligned carbon nanotubes Ultra-low Pt loading Membrane electrode assembly

Observational characteristics of SiO masers around VX Sgr

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Research in Astronomy and Astrophysics 2020年第12期20卷 196-204页

作者： Jiang-Bo Su Zhi-Qiang shen Xi Chen Jing Liu yan Wang Yi-bin Zhao Department of Physics and Electronics Yuncheng UniversityYuncheng 044000China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China

SiO maser VLBA observations toward VX Sgr are performed at five epochs, and lots of maser spots are obtained. We make a statistical analysis on these spots. It is shown that the apparent sizes and the fluxes of maser spots decrease with increasing the distance from the central star. In addition, the similarity between the v = 1,2(J =1–0) spectrums increases with epochs, consistent with the full width at half maximum(FWHM), while the total fluxes increase. The results may be related to the changeable pumping mechanisms.

关键词： masers stars:individual(VX Sgr) techniques:interferometric turbulence

Function-reversible facets enabling SrTiO_(3)nanocrystals for improved photocatalytic hydrogen evolution

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Frontiers in Energy 2024年第1期18卷 101-109页

作者： bin WANG Bei AN Xiaoqian LI Shaohua shen School of Physics Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter(Ministry of Education)Key Laboratory of Shaanxi for Advanced Materials and Mesoscopic PhysicsXi’an Jiaotong UniversityXi’an 710049China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049China

It has been widely reported that,for faceted nanocrystals,the two adjacent facets with different band levels contribute to promoted charge separation,and provide active sites for photocatalytic reduction and oxidation reaction,*** such cases,only one family of facets can be used for photocatalytic hydrogen ***,by using SrTiO_(3)nanocrystals enclosed by{023}and{001}facets as a model photocatalyst,this paper proposed a strategy to achieve the full-facets-utilization of the nanocrystals for photocatalytic hydrogen via chemically depositing Pt nanoparticles on all *** photo-deposition experiment of CdS provided direct evidence to demonstrate that the{023}facets which were responsible for photooxidation reaction can be function-reversed for photocatalytic hydrogen evolution after depositing Pt nanoparticles,together with the{001}***,the full-facets-utilization led to a much-improved activity for photocatalytic hydrogen,in contrast to those SrTiO_(3)nanocrystals with only{001}facets deposited by Pt nanoparticles via a photo-deposition method.

关键词： SrTiO_(3)nanocrystals crystal facets photocatalysis hydrogen evolution

One-Pot Synthesis of Triarylmethanes via Metal-Free Reductive Coupling of Diaryl Ketones, Tosylhydrazide, and Arylboronic Acids

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Chinese Journal of Chemistry 2016年第10期34卷 1033-1038页

作者： Xu shen Ningning Gu Ping Liu Xiaowei Ma Jianwei Xie yan Liu bin Dai School of Chemistry and Chemical Engineering the Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan Shihezi University Shihezi Xinjiang 832003 China

Synthesis of triarylmethanes via metal-free reductive coupling of diaryl ketone, tosylhydrazide, and arylboronic acids has been developed. This methodology is realized via one-pot two-step reactions involving the preparation of N-tosylhydrazones by reacting tosylhydrazide with diaryl ketone derivatives, followed by the reductive coupling with arylboronic acid in the presence of potassium carbonate to afford various triarylmethanes analogues in moder- ate to good yields. Importantly, the system presented here enables the use of easily accessible starting materials and a series of substrates with diverse functional group could be tolerant in this reaction. This approach could also be particularly useful for the synthesis of triaryl-substituted carbazolyl compounds.

关键词： diaryl ketone arylboronic acid tosylhydrazide one-pot

Application of molybdenum target X-ray photography in imaging analysis of caudal intervertebral disc degeneration in rats

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World Journal of Clinical Cases 2020年第16期8卷 3431-3439页

作者： Qi-Hang Su yan Zhang bin shen Yong-Chao Li Jun Tan Department of Orthopedics Shanghai East HospitalTongji University School of MedicineShanghai 200120China

BACKGROUND Conventional plain X-ray images of rats,the most common animals used as degeneration models,exhibit unclear vertebral structure and blurry intervertebral disc spaces due to their small size,slender vertebral *** To apply molybdenum target X-ray photography in the evaluation of caudal intervertebral disc(IVD)degeneration in rat *** Two types of rat caudal IVD degeneration models(needle-punctured model and endplate-destructed model)were established,and their effectiveness was verified using nuclear magnetic resonance *** target inspection and routine plain X-ray were then performed on these ***,four observers were assigned to measure the intervertebral height of degenerated segments on molybdenum target plain X-ray images and routine plain X-ray images,*** degeneration was evaluated and statistical analysis was subsequently *** Nine rats in the needle-punctured model and 10 rats in the endplate-destructed model were *** with routine plain X-ray images,molybdenum target plain X-ray images showed higher clarity,stronger contrast,as well as clearer and more accurate structural *** McNemar test confirmed that the difference was statistically significant(P=0.031).In the two models,the reliability of the intervertebral height measured by the four observers on routine plain X-ray images was poor(ICC<0.4),while the data obtained from the molybdenum target plain X-ray images were more *** target inspection can obtain clearer images and display fine calcification in the imaging evaluation of caudal IVD degeneration in rats,thus ensuring a more accurate evaluation of degeneration.

关键词： Molybdenum target inspection Routine plain X-ray Intervertebral disc degeneration model Animal experiment Imaging analysis McNemar test

Packet track and traceback mechanism against denial of service attacks

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 51-58页

作者： LI Li shen Su-bin Institute of Information Network Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China

The denial of service attack is a main type of threat on the Internet today. On the basis of path identification （Pi） and Internet control message protocol （ICMP） traceback （iTrace） methods, a packet track and traceback mechanism is proposed, which features rapid response and high accuracy. In this scheme, routers apply packet marking scheme and send traceback messages, which enables the victim to design the path tree in peace time. During attack times the victim can trace attackers back within the path tree and perform rapid packet filtering using the marking in each packet. Traceback messages overcome Pi＇s limitation, wherein too much path information is lost in path identifiers; whereas path identifiers can be used to expedite the design of the path-tree, which reduces the high overhead in iTrace. Therefore, our scheme not only synthesizes the advantages but also compromises the disadvantages of the above two methods. Simulation results with NS-2 show the validity of our scheme.

关键词： denial of service (DoS) attack traceback packet marking Pi