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Asian Journal of Andrology 2011年第6期13卷 812-818页

作者： Huan-Tao Zong xiao-xia peng Chen-Chen Yang yong Zhang Department of Urology Beijing Chao Yang Hospital University Beijing 100069 China School of Public Health and Family Medicine Capital Medical University Beijing 100069 China

5α-reductase inhibitors （5α-RIs）, including finasteride and dutasteride, are commonly used medical therapies for benign prostatic hyperplasia （BPH）. Many studies reported that preoperative 5α-RI had impact on intraoperative haemorrhage during surgery for BPH, but it was still in controversial. So, we conducted a systematic review of the effects and mechanisms of 5α-RIs on intraoperative bleeding for BPH. MEDLINE, EMBASE, the Cochrane Controlled Trail Register of Controlled Trials and the reference lists of retrieved studies were searched in the analysis. Sixteen publications involving 15 different randomized controlled trials （RCTs） and a total of 1156 patients were used in the analysis, including 10 RCTs for finasteride and five RCTs for dutasteride. We found that preoperative finasteride treatment decreases microvessel density （MVD） in resected prostate specimens. Total blood loss, blood loss per gram of resected prostate tissue and decreases in haemoglobin were all greatly reduced in the finasteride group as compared to controls. Dutasteride appeared to have no effect on bleeding. This meta-analysis shows that preoperative finasteride treatment could decrease intraoperative haemorrhage during surgery for BPH. Preoperative dutasteride had no effect on intraoperative haemorrhage, but further high-qualitv prospective studies are still needed to confirm this observation.

关键词： 5α-reductase inhibitor benign prostate hyperplasia haemorrhage meta-analysis microvessel density

Photometric redshift estimation for quasars by integration of KNN and SVM

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Research in Astronomy and Astrophysics 2016年第5期16卷 31-40页

作者： Bo Han Hong-peng Ding Yan-xia Zhang yong-Heng Zhao International School of Software Wuhan University Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences

The massive photometric data collected from multiple large-scale sky surveys offer significant opportunities for measuring distances of celestial objects by photometric redshifts. However, catastrophic failure is an unsolved problem with a long history and it still exists in the current photometric redshift estimation approaches （such as the k-nearest neighbor （KNN） algorithm）. In this paper, we propose a novel two-stage approach by integration of KNN and support vector machine （SVM） methods together. In the first stage, we apply the KNN algorithm to photometric data and estimate their corresponding Zphot. Our analysis has found two dense regions with catastrophic failure, one in the range of Zphot E [0.3, 1.2] and the other in the range of Zphot E [1.2, 2.1]. In the second stage, we map the photometric input pattern of points falling into the two ranges from their original attribute space into a high dimensional feature space by using a Gaussian kernel function from an SVM. In the high dimensional feature space, many outliers resulting from catastrophic failure by simple Euclidean distance computation in KNN can be identified by a classification hyperplane of SVM and can be further corrected. Experimental results based on the Sloan Digital Sky Survey （SDSS） quasar data show that the two-stage fusion approach can significantly mitigate catastrophic failure and improve the estimation accuracy of photometric redshifts of quasars. The percents in different /△z/ ranges and root mean square （rms） error by the integrated method are 83.47%, 89.83%, 90.90% and 0.192, respectively, compared to the results by KNN （71.96%, 83.78%, 89.73% and 0.204）.

关键词： catalogs -- galaxies: distances and redshifts -- methods: statistical -- quasars: general --surveys -- techniques: photometric

Global Optimization of a Class of Nonconvex Quadratically Constrained Quadratic Programming Problems

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Acta Mathematica Sinica,English Series 2011年第9期27卷 1803-1812页

作者： yong xia LMIB of the Ministry of Education School of Mathematics and Systems Science Beihang University Beijing 100191 P. R. China

In this paper we study a Class of nonconvex quadratically constrained quadratic programming problems generalized from relaxations of quadratic assignment problems. We show that each problem is polynomially solved. Strong duality holds if a redundant constraint is introduced. As an application, a new lower bound is proposed for the quadratic assignment problem.

关键词： Nonconvex programming quadratically constrained quadratic programming quadratic assignment problem polynomial solvability strong duality

A Deep Deterministic Policy Gradient-Based Method for Enforcing Service Fault-Tolerance in MEC

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Chinese Journal of Electronics 2024年第4期33卷 899-909页

作者： Tingyan LONG peng CHEN Yunni xia yong MA xiaoning SUN Jiale ZHAO Yifei LYU College of Computer Science Chongqing University School of Computer and Software Engineering Xihua University School of Computer and Information Engineering Jiangxi Normal University School of Computer and Information Science Chongqing Normal University

Mobile edge computing(MEC) provides edge services to users in a distributed and on-demand *** to the heterogeneity of edge applications, deploying latency and resource-intensive applications on resourceconstrained devices is a key challenge for service providers. This is especially true when underlying edge infrastructures are fault and error-prone. In this paper, we propose a fault tolerance approach named DFGP, for enforcing mobile service fault-tolerance in MEC. It synthesizes a generative optimization network(GON) model for predicting resource failure and a deep deterministic policy gradient(DDPG) model for yielding preemptive migration *** show through extensive simulation experiments that DFGP is more effective in fault detection and guaranteeing quality of service, in terms of fault detection accuracy, migration efficiency, task migration time, task scheduling time,and energy consumption than other existing methods.

关键词： Fault tolerance Multi-access edge computing Processor scheduling Fault detection Image edge detection Fault tolerant systems Quality of service

Shale Gas Reservoir Evaluation by Geophysical Measurements:A Case Study of the Upper Ordovician–Lower Silurian in the Fenggang Block,Northern Guizhou Province

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1310-1321页

作者： xia peng FU yong GUO Chuan YANG Zhen HUANG Jinqiang MOU Yuliang Resource and Environmental Engineering College Guizhou UniversityGuiyang 550025China Key Laboratory of Geological Resources and the Environment Guizhou UniversityGuivang 550025China College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China

With the aid of geophysical measurements,including seventeen two-dimensional(2 D)seismic lines and the well logging curves of well FGY1,the structure and reservoir characteristics of the Upper Ordovician–Lower Silurian strata in the Fenggang block,northern Guizhou Province,were analyzed thoroughly to identify desert areas and favorable *** results show that Longmaxi-Wufeng is the most prospect-rich formation,consisting of a thick succession of overmature black shale,this formation remaining partially in the Suiyang,Fenggang and Jianchaxi *** Longmaxi-Wufeng shale,especially the lower member,was deposited in a reducing low-energy environment with relatively high U content and a low Th/U *** this shale,the organic matter type(sapropelic and humic-sapropelic),total organic carbon(TOC)content,gas content,gas adsorption capacity,vitrinite reflectance and brittle mineral content are profitable for shale gas preservation and *** fractures of this shale were closed because of its high overburden *** gas adsorption capacity of this shale increases with increasing TOC content and *** the Longmaxi-Wufeng Formation at well FGY1,the most favorable intervals are in the depth ranges of 2312.4–2325.1 m and 2325.8–2331.1 m.

关键词： shale gas reservoir property geophysics Longmaxi-Wufeng Guizhou

Cytotoxic T lymphocyte response induced by an improved synthetic lipopeptide vaccine against cervical cancer

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Acta Pharmacologica Sinica 2007年第5期28卷 695-702页

作者： Dao-hua XU~(1,5),Chen-hui ZHOU~2,yong-peng xia~3,Zong-ying QIU~3,Yu-zhang WU~4,Zheng-cai JIA~4,Wei ZHOU~4~1 Department of Pharmacology and ~2 School of Nursing,Guangdong Medical College,Zhanjiang 524023,China ~3 Department of PharmacyChongqing University of Medical Science,Chongqing 400016,China,~4 Institute of Immunology PLA,Third Military Medical University,Chongqing 400038,China DepartmentofPharmacology SchoolofNursing GuangdongMedicalCollegeZhanjiang524023China DepartmentofPharmacy ChongqingUniversityofMedicalScienceChongqing400016 InstituteofImmunology PLAThirdMilitaryMedicalUniv

Aim:To explore cytotoxic T lymphocyte （CTL） response induced by the lipopeptidevaccine against cervical ***:The immunological effect inducingCDS+ T cell-mediated cytotoxicity was investigated in human leukocyte antigen（HLA）-A2 transgenic mice and peripheral blood mononuclear cells （PBMC） ofhealthy HLA-A2.1+blood *** activity of specific CTL was measured byusing a standard 4 h51Cr release *** content of major histocompatibilitycomplex （MHC） I on T2 cells and the expression of immune molecules on dendriticcells （DC） were detected by flow cytometry,and the concentrations of interleukin（IL）-12 and interferon-γ were determined by ***:The lipopeptideinduced a strong epitope-specific CTL response both in vivo （transgenic mice）and in vitro （human PBMC）.This CTL induction was critically dependent on thepresence of the helper T lymphocyte epitope in transgenic mice,and the presenceof a lipid tail bypassed the need for an *** stability and persistence ofthe antigenic complex formed with the lipopeptide increased in comparison withthe CTL parental *** lipopeptide could induce the production of IL-12 inDC,but not the maturation of DC ***:The combination of CTLand the T helper epitope and lipid molecule can remarkably improve the immuno-genicity of the CTL peptide,the mechanism of which is associated with an in-crease in the stability and persistence of the antigenic complex formed with thelipopeptide and in the production of IL-12 in DC induced by the *** can be considered a more effective vaccine type for human being.

关键词： epitope cervical cancer lipopeptide vaccine

Niobium doping induced mirror twin boundaries in MBE grown WSe2 monolayers

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Nano Research 2020年第7期13卷 1889-1896页

作者： Bo Wang Yipu xia Junqiu Zhang Hannu-Pekka Komsa Maohai Xie yong peng Chuanhong Jin Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education School of Physical Science and TechnologyLanzhou UniversityLanzhou 730000China State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310024China Physics Department The University of Hong KongPokfulam RoadHong Kong 999077China Department of Applied Physics Aalto University00076 AaltoFinland Hunan Institute of Advanced Sensing and Information Technology Xiangtan UniversityXiangtan 411201China

Mirror twin boundary(MTB)brings unique one-dimensional(1D)physics and properties into two-dimensional(2D)transition metal dichalcogenides(TMDCs),but they were rarely observed in non-Mo-based ***,by post growth Nb doping,high density 4|4E-W and 4|4P-Se mirror twin boundaries(MTBs)were introduced into molecular beam epitaxy(MBE)grown WSe2 *** them,4|4E-W MTB with a novel structure was discovered experimentally for the first time,while 4|4P-Se MTBs present a random permutations of W and Nb,forming a 1D alloy *** between the doped and non-doped WSe2 confirmed that Nb dopants are essential for MTB ***,quantitative statistics reveal the areal density of MTBs is directly proportional to the concentration of Nb *** unravel the injection pathway of Nb dopants,first-principles calculations about a set of formation energies for excess Nb atoms with different configurations were conducted,based on which a model explaining the origin of MTBs introduced by excess metal was *** conclude that the formation of MTBs is mainly driven by the collective evolution of excess Nb atoms introduced into the lttice of host WSe2 crystal and subsequent displacement of metal atoms(W or Nb).This study provides a novel way to tailor the MTBs in 2D TMDC materials via proper metal doping and presents new opportunities for exploring the intriguing properties.

关键词： mirror twin boundaries niobium doping molecular beam epitaxy transition metal dichalcogenides niobium tungsten diselenide

Discriminative Histogram Intersection Metric Learning and Its Applications

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Journal of Computer Science & Technology 2017年第3期32卷 507-519页

作者： peng-Yi Hao Yang xia xiao-Xin Li Sei-ichiro Kamata Sheng-yong Chen College of Computer Science and Technology Zhejiang University of Technology Hangzhou 310023 China Graduate School of Information Production and Systems Waseda University Kitakyushu 808-0135 Japan

In this paper, a novel method called discriminative histogram intersection metric learning （DHIML） is proposed for pair matching and classification. Specifically, we introduce a discrimination term for learning a metric from binary infor-mation such as same/not-same or similar/dissimilar, and then combine it with the classification error for the discrimination in classifier construction. Compared with conventional approaches, the proposed method has several advantages. 1） The histogram intersection strategy is adopted into metric learning to deal with the widely used histogram features effectively. 2） By introducing discriminative term and classification error term into metric learning, a more discriminative distance metric and a classifier can be learned together. 3） The objective function is robust to outliers and noises for both features and labels in the training. The performance of the proposed method is tested on four applications： face verification, face-track identification, face-track clustering, and image classification. Evaluations on the challenging restricted protocol of Labeled Faces in the Wild （LFW） benchmark, a dataset with more than 7000 face-tracks, and Caltech-101 dataset validate the robustness and discriminability of the proposed metric learning, compared with the recent state-of-the-art approaches.

关键词： metric learning pair matching image classification face verification

The in vitro and in vivo toxicity of gold nanoparticles

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Chinese Chemical Letters 2017年第4期28卷 691-702页

作者： Yan-peng Jia Bu-Yun Ma xia-Wei Wei Zhi-yong Qian State Key Laboratory of Biotherapy Collaborative Innovation Center of Biotherapy West China Hospital Sichuan University Chengdu 610041 China Department of Ultrasound West China Hospital Sichuan University Chengdu 610041 China

Gold nanoparticles,owing to their unique physicochemical and optical properties,well-established synthetic methods and easy modifications,have been widely used in biomedical ***,for their safe and efficient applications,much attention has been given to the toxicological evaluations of gold nanoparticles in biological systems.A large number of studies focusing on this problem have been carried out during the past ***,the researches on gold nanoparticles toxicity still remain fragmentary and even contradictory with each *** may be caused by the variety in experimental *** this review,we aim to provide a better understanding about the in vitro and in vivo toxicity of gold nanoparticles by reviewing and describing the up to date literatures related to this problem and we mainly focused on these properties such as the particle size and shape,the surface charge and ***,we also summarized the adverse effect of gold nanoparticles on immune systems and analyzed the origin of the toxicity.

关键词： Gold nanoparticles Toxicity Size Shape Surface modification In vitro In vivo

Efficient and recyclable Rh-catalytic system with involvement of phosphine-functionalized phosphonium-based ionic liquids for tandem hydroformylation—acetalization

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Green Energy & Environment 2017年第4期2卷 419-427页

作者： peng Wang xia Chen Dong-Liang Wang yong-Qi Li Ye Liu Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular Engineering East China Normal University

The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dppm-Q, dppe-Q, dppp-Q and dppb-Q, the incorporated phosphino-fragments were responsible for Rh-catalyzed hydroformylation and the phosphoniums were in charge of the subsequent acetalization as the Lewis acid catalysts. Moreover, the diphosphonium-based ionic liquid of dppb-DQ could be applied as a co-solvent to immobilize the Rh/dppb-Q catalytic system with the advantages of the improved catalytic performance, the available catalyst recyclability, and the wide generality for the substrates.

关键词： Phosphines Phosphonium-based ionic liquids Bi-functional ligands Recyclability of homogeneous catalysts Tandem hydroformylationeacetalization