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Combining clinical parameters and multiparametric magnetic resonance imaging to stratify biopsy-naïve men for an optimum diagnostic strategy with prostate-specific antigen 4 ng ml^(−1) to 10 ng ml^(−1)

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Asian Journal of Andrology 2023年第4期25卷 492-498页

作者： Chi-Chen Zhang Xiang Tu Tian-Hai Lin Di-ming Cai Ling Yang Shi qiu Zhen-hua Liu Lu Yang Qiang Wei Department of Urology Institute of UrologyWest China HospitalSichuan UniversityChengdu 610041China Department of Ultrasound West China HospitalSichuan UniversityChengdu 610041China Department of Radiology West China HospitalSichuan UniversityChengdu 610041China

We attempted to perform risk categories based on the free/total prostate-specific antigen ratio (%fPSA), prostate-specific antigen(PSA) density (PSAD, in ng ml^(−2)), and multiparametric magnetic resonance imaging (mpMRI) step by step, with the goal ofdetermining the best clinical diagnostic strategy to avoid unnecessary tests and prostate biopsy (PBx) in biopsy-naïve men with PSAlevels ranging from 4 ng ml^(−1) to 10 ng ml^(−1). We included 439 patients who had mpMRI and PBx between August 2018 and July2021 (West China Hospital, Chengdu, China). To detect clinically significant prostate cancer (csPCa) on PBx, receiver-operatingcharacteristic (ROC) curves and their respective area under the curve were calculated. Based on %fPSA, PSAD, and ProstateImaging-Reporting and Data System (PI-RADS) scores, the negative predictive value (NPV) and positive predictive value (PPV) werecalculated sequentially. The optimal %fPSA threshold was determined to be 0.16, and the optimal PSAD threshold was 0.12 for%fPSA ≥0.16 and 0.23 for %fPSA <0.16, respectively. When PSAD <0.12 was combined with patients with %fPSA ≥0.16, the NPVof csPCa increased from 0.832 (95% confidence interval [CI]: 0.766–0.887) to 0.931 (95% CI: 0.833–0.981);the detection rateof csPCa was similar when further stratified by PI-RADS scores (P = 0.552). Combining %fPSA <0.16 with PSAD ≥0.23 ng ml^(−2)predicted significantly more csPCa patients than those with PSAD <0.23 ng ml^(−2) (58.4% vs 26.7%, P < 0.001). Using PI-RADSscores 4 and 5, the PPV was 0.739 (95% CI: 0.634–0.827) when further stratified by mpMRI results. In biopsy-naïve patientswith PSA level of 4–10 ng ml^(−1), stratification of %fPSA and PSAD combined with PI-RADS scores may be useful in the decisionmaking process prior to undergoing PBx.

关键词： multiparametric magnetic resonance imaging predictive value prostate biopsy prostate cancer prostate-specific antigen PSA-derived parameter

Empirical Likelihood for Mixed-effects Error-in-variables Model

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Acta Mathematicae Applicatae Sinica 2009年第4期25卷 561-578页

作者： qiu-hua Chen Ping-shou Zhong Heng-jian Cui Mathematical & Physical Science School North China Electric Power University Beijing 102206 China Department of Statistics and Financial Mathematics Beijing Normal University Beijing 100875 China

This paper mainly introduces the method of empirical likelihood and its applications on two different models. We discuss the empirical likelihood inference on fixed-effect parameter in mixed-effects model with error-in-variables. We first consider a linear mixed-effects model with measurement errors in both fixed and random effects. We construct the empirical likelihood confidence regions for the fixed-effects parameters and the mean parameters of random-effects. The limiting distribution of the empirical log likelihood ratio at the true parameter is X2p＋q, where p, q are dimension of fixed and random effects respectively. Then we discuss empirical likelihood inference in a semi-linear error-in-variable mixed-effects model. Under certain conditions, it is shown that the empirical log likelihood ratio at the true parameter also converges to X2p＋q. Simulations illustrate that the proposed confidence region has a coverage probability more closer to the nominal level than normal approximation based confidence region.

关键词： Confidence region empirical likelihood mixed-effects model

Rolling motion behavior of rockfall on gentle slope:an experimental approach

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Journal of Mountain Science 2017年第8期14卷 1550-1562页

作者： CUI Sheng-hua PEI Xiang-jun huaNG Run-qiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology

The effects of slope surface material, slope gradient, block shape, and block mass conditions on rockfall rolling velocity were estimated with orthogonal test approach. Visual analysis shows that the importance of the factors is slope surface material > slope gradient > block shape > block mass. All the factors except block mass have the F value greater than the critical value, suggesting that these three factors are the key factors affecting the rockfall rolling velocity. Factor interaction analysis shows that the effect of the slope gradient relies largely on the slope surface conditions, and the block shape has little influence if the slope gradient is larger than a critical value. An empirical model considering the three key factors is proposed to estimate the rolling velocity, of which the error is limited to 5% of the testing value. This model is validated by 73 field tests, and the prediction shows excellent correlation with the site test. Thus, this analysis can be used as a tool in the rockfall behavior analysis.

关键词： Rockfall Rolling motion Experiment approach Gentle slope Orthogonal test

Evaluation of packet loss impairment on streaming video

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 131-136页

作者： RUI hua-xia LI Chong-rong qiu Sheng-ke Network Research Center Tsinghua University Beijing 100084 China Network Research Center Tsinghua University Beijing 100084 China Network Research Center Tsinghua University Beijing 100084 China

Video compression technologies are essential in video streaming application because they could save a great amount of network resources. However compressed videos are also extremely sensitive to packet loss which is inevitable in today's best effort IP network. Therefore we think accurate evaluation of packet loss impairment on compressed video is very important. In this work, we develop an analytic model to describe these impairments without the reference of the original video (NR) and propose an impairment metric based on the model, which takes into account both impairment length and impairment strength. To evaluate an impaired frame or video, we design a detection and evaluation algorithm (DE algorithm) to compute the above metric value. The DE algorithm has low computational complexity and is currently being implemented in the real-time monitoring module of our HDTV over IP system. The impairment metric and DE algorithm could also be used in adaptive system or be used to compare diffeient error concealment strategies.

关键词： Packet loss, Video streaming, MPEG-2 video, Video quality, No-Reference

Liquid film dryout model for predicting critical heat flux in annular two-phase flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 398-417页

作者： Bo JIAO Li-min qiu Jun-liang LU Zhi-hua GAN Institute of Refrigeration and Cryogenic Engineering Zhejiang University Hangzhou 310027 China

Gas-liquid two-phase flow and heat transfer can be encountered in numerous fields, such as chemical engineering, refrigeration, nuclear power reactor, metallurgical industry, spaceflight. Its critical heat flux (CHF) is one of the most important factors for the system security of engineering applications. Since annular flow is the most common flow pattern in gas-liquid two-phase flow, predicting CHF of annular two-phase flow is more significant. Many studies have shown that the liquid film dryout model is successful for that prediction, and determining the following parameters will exert predominant effects on the accuracy of this model: onset of annular flow, inception criterion for droplets entrainment, entrainment fraction, droplets deposition and entrainment rates. The main theoretical results achieved on the above five parameters are reviewed; also, limitations in the existing studies and problems for further research are discussed.

关键词： Annular two-phase flow Critical heat flux (CHF) Liquid film dryout Deposition rate Entrainment rate

The Discrete Subgroups and Jфrgensen’s Inequality for SL(m, Cp)

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Acta Mathematica Sinica,English Series 2013年第3期29卷 417-428页

作者： Wei Yuan qiu Jing hua YANG Yong Cheng YIN Department of Mathematics Fudan University Institute of Mathematics AMSS Chinese Academy of Sciences Department of Mathematics Zhejiang University

In this paper, we give discreteness criteria of subgroups of the special linear group on Qp or Cp in two and higher dimensions. Jorgensen＇s inequality gives a necessary condition for a non- elementary group of M6bius... 详细信息

关键词： Jorgensen's inequality discreteness criteria non-Archimedean space

Intramammary expression and therapeutic effect of a human lysozyme-expressing vector for treating bovine mastitis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第4期7卷 324-330页

作者： SUN huai-chang XUE Fang-ming QIAN Ke FANG Hao-xia qiu hua-lei ZHANG Xin-yu YIN Zhao-hua School of Veterinary Medicine Yangzhou University Yangzhou 225009 China

To develop a gene therapy strategy for treating bovine mastitis, a new mammary-specific vector containing human lysozyme (hLYZ) cDNA and kanamycin resistance gene was constructed for intramammary expression and clinical studies. After one time acupuncture or intracisternal infusion of healthy cows with 400 μg of the p215C3LYZ vector, over 2.0 μg/ml of rhLYZ could be detected by enzymatic assay for about 3 weeks in the milk samples. Western blotting showed that rhLYZ secreted into milk samples from the vector-injected cows had molecular weight similar to that of the natural hLYZ in human colostrums. Twenty days after the primary injection, the quarters were re-injected with the same vector by quarter acupuncture and even higher concentrations of rhLYZ could be detected. Indirect competitive ELISA of milk samples showed that the vector injection did not induce detectable humoral immune response against hLYZ. Clinical studies showed that twice acupuncture of quarters with the p215C3LYZ vector had overt therapeutic effect on clinical and subclinical mastitis previously treated with antibiotics, including disappearance of clinical symptoms and relatively high microbiological cure rates. These data provide a solid rationale for using the vector to develop gene therapy for treating bovine mastitis.

关键词： Human lysozyme cDNA Mammary-specific vector Expression Mastitis Gene therapy

Selfinjective Koszul Algebras of Finite Complexity

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2179-2198页

作者： Jin Yun GUO Ai hua LI qiu Xian WU Department of Mathematics Xiangtan University Xiangtan 411105 P. R. China Department of Mathematics Hu'nan Normal University Changsha 410081 P. R. China

In this paper, we study selfinjective Koszul algebras of finite complexity. We prove that the complexity is a nonnegative integer when it is finite; and that the category Yt of modules with complexity less or equal to t, is resolving and coresolving. We show that for each 0 ≤ 1 ≤ m there exist a family of modules of complexity 1 parameterized by G（l, m）, the Grassmannian of l-dimensional subspaces of an m-dimensional vector space V, for the exterior algebra of V. Using complexity, we also give a new approach to the representation theory of a tame symmetric algebra with vanishing radical cube over an algebraically closed field of characteristic 0, via skew group algebra of a finite subgroup of SL（2, C） over the exterior algebra of a 2-dimensional vector space.

关键词： selfinjective Koszul algebra complexity skew group algebra tame symmetric algebra

Tribology properties of composite layer of CrMoCu alloy cast iron by combined treatment of ion nitrocarburizing and sulphurizing

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中国有色金属学会会刊：英文版 2004年第z1期14卷 315-318页

作者： MA Shi-ning HU Chun-hua LI Xin qiu Ji Department of Materials Science and Engineering Academy of Armored Force Engineering Beijing 100072 China Department of Materials Science and EngineeringAcademy of Armored Force Engineering Beijing 100072 China Department of Materials Science and EngineeringAcademy of Armored Force Engineering Beijing 100072 China Department of Materials Science and EngineeringAcademy of Armored Force Engineering Beijing 100072 China

Composite layer with nitrocarbonide and sulfide was made on the surface of CrMoCu alloy cast iron by combined treatment of ion nitrocarburizing and sulphurizing. The composite layer is composed of sulfide layer, nitrocarbonide hypo-surface layer and its diffusing layer, the size of sulfide globular grains distributing equably on the surface is in nano-micron-scale, and the phase structure of the composite layer is composed of FeS, FeS1-x, Fe2C and Fe3N. Under oil lubrication, sulphurized surface shows good scuffing-resistance only under low velocity, and nitrocarburized and sulphurized surface greatly improves the scuffing-resistance and wear-resistance of CrMoCu alloy cast iron, its integrated friction and wear properties are better than those of the plain and sulphurized surfaces under all the velocities.

关键词： ion nitrocarburizing ion sulphurizing combined treatment friction and wear properties