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Combination therapy for erectile dysfunction： an update review

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Asian Journal of Andrology 2011年第3期13卷 382-390,510,511页

作者： Rohit R Dhir Hao-cheng Lin steven E Canfield Run Wang Division of Urology University of Texas Medical School at Houston Houston TX 77030 USA Department of Urology Affiliated Drum Tower Hospital Nanjing University School of Medicine Nanjing 210008 China Department of Urology University of Texas MD Anderson Cancer Center Houston TX 77030 USA

The introduction of oral phosphodiesterase-5 inhibitors （PDE51s） in the late 1990s and early 2000s revolutionized the field of sexual medicine and PDE51s are currently first-line monotherapy for erectile dysfunction （ED）. However, a significant proportion of patients with complex ED will be therapeutic non-responders to PDE51 monotherapy. Combination therapy has recently been adopted for more refractory cases of ED, but a critical evaluation of current combination therapies is lacking. A thorough PubMed and Cochrane Library search was conducted focusing on the effectiveness of combination therapies for ED in therapeutic non-responders to PDE51 therapy. Journal articles spanning the time period between January 1990 and December 2010 were reviewed. Criteria included all pertinent review articles, randomized controlled trials, cohort studies and retrospective analyses. References from retrieved articles were also manually scanned for additional relevant publications. Published combination therapies include PDE51 plus vacuum erectile device （VED）, intraurethral medication, intracavernosal injection （ICI）, androgen supplement, a-blocker or miscellaneous combinations. Based on this review, some of these combination treatments appeared to be quite effective in preliminary testing. Caution must be advised, however, as the majority of combination therapy articles in the last decade have numerous limitations including study biases and small subject size. Regardless of limitations, present combination therapy research provides a solid foundation for future studies in complex ED management.

关键词： combination therapy intracavernosal injection erectile dysfunction phosphodiesterase-5 inhibitors vacuum erectile device

Color-coded perfluorocarbon nanodroplets for multiplexed ultrasound and photoacoustic imaging

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Nano Research 2019年第4期12卷 741-747页

作者： Daniela y. Santiesteban Kristina A. Hallam steven K. yarmoska Stanislav y. Emelianov Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory University Atlanta GA 30332 USA School of Electrical & Computer Engineering Georgia Institute of Technology Atlanta GA 30332 USA

Laser-activated perfluorocarb on n anodroplets are an emerging class of phase-cha nge, dual-c ontrast age nts that can be utilized in ultraso und and photoacoustic imaging. Through the ability to differe ntiate subpopulations of nano droplets via laser activatio n at differe nt wavelengths of n ear-infrared light, optically-triggered color-coded perfluorocarb on nano droplets prese nt themselves as an attractive tool for multiplexed ultrasound and photoacoustic imaging. In particular, laser-activated droplets can be used to provide quantitative spatiotemporal information regarding distinct biological targets, allowing for their potential use in a wide range of diagnostic and therapeutic applications. In the work prese nted, laser-activated color-coded perfluorocarb on nan odroplets are syn thesized to selectively resp ond to laser irradiati on at corresp on ding wavele ngths. The dyn amic ultraso und and photoacoustic signals produced by laser-activated perfluorocarbon nano droplets are evaluated in situ prior to implementation in a murine model. In vivo, these particles are used to distinguish unique particle trafficking mechanisms and are show n to provide ultraso und and photoacoustic contrast for up to 72 hours within lymphatics. Overall, the con ducted studies show that laser-activated color-coded perfluorocarbo n nano droplets are a promising agent for multiplexed ultraso und and photoacoustic imaging.

关键词： multiplexed imaging perfluorocarbon nanodroplets photoacoustic imaging ultrasound imaging molecular targets

The dimension split element-free Galerkin method for three-dimensional potential problems

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Acta Mechanica Sinica 2018年第3期34卷 462-474页

作者： Z.J.Meng H.cheng L.D.Ma y.M.cheng Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University School of Applied Science Taiyuan University of Science and Technology Department of Civil Engineering Shanghai University School of Materials Science and Engineering Taiyuan University of Science and Technology

This paper presents the dimension split element-free Galerkin （DSEFG） method for three-dimensional potential problems, and the corresponding formulae are obtained. The main idea of the DSEFG method is that a three-dimensional potential problem can be transformed into a series of two-dimensional problems. For these two-dimensional problems, the improved moving least-squares （IMLS） approximation is applied to construct the shape function, which uses an orthogonal function system with a weight function as the basis functions. The Galerkin weak form is applied to obtain a discretized system equation, and the penalty method is employed to impose the essential boundary condition. The finite difference method is selected in the splitting direction. For the purposes of demonstration, some selected numerical examples are solved using the DSEFG method. The convergence study and error analysis of the DSEFG method are presented. The numerical examples show that the DSEFG method has greater computational precision and computational efficiency than the IEFG method.

关键词： Dimension split method Improved moving least-squares (IMLS) approximation Improved element-free Galerkin (IEFG) method Finite difference method (FDM) Dimension split element-free Galerkin (DSEFG) method Potential problem

Comparative in vitro Study on Pure Metals(Fe,Mn,Mg,Zn and W) as Biodegradable Metals

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Journal of Materials Science & Technology 2013年第7期29卷 619-627页

作者： J.cheng B.Liu y.H.Wu y.F.Zheng Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary StudiesPeking University State Key Laboratory for Turbulence and Complex System and Department of Materials Science and Engineering College of EngineeringPeking University

Five pure metals including Fe, Mn, Mg, Zn and W have been investigated on their corrosion behavior and in vitro biocompatibility by electrochemical measurement, static immersion test, contact angle measurement, cytotoxicity and hemocompatibility tests. It is found that the sequence of corrosion rate of five metals in Hank＇s solution from high to low is： Mg 〉 Fe 〉 Zn 〉 Mn 〉 W. Fe, Mg and W show no cytotoxicity to L929 and ECV304 cells, Mn induces significant cytotoxicity to both L929 and ECV304 cells, and Zn has almost no inhibition effect on the metabolic activities of ECV304 while largely reduces the cell viability of L929 cells. The hemolysis percentage of five pure metals is lower than 5% except for Mg and platelets adhered on Zn has been activated and pseudopodia-like structures can be observed while platelets on the other four metals keep normal.

关键词： Biodegradable metals Cytotoxicity Corrosion Biocompatibflity

Protein profiles in various epididymal segments of normal and castrated rats

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Asian Journal of Andrology 2000年第1期2卷 57-64页

作者： PremenduP.Mathur AileenMarshall C.y.cheng School of Life Sciences Pondicherry University Pondicherry-605 014 India The Population Council Center for Biomedical Research 1230 York Avenue New York NY 10021 USAThe Population Council Center for Biomedical Research 1230 York Avenue New York 10021 USAThe Population Council Center for Biomedical Research 1230 York Avenue New York 10021 USA

Aim: Epididymal proteins are known to play an important role in the maturation of spermatozoa, we ougnt to deter-mine if there are regional differences in androgen-dependent epididymal proteins. Methods: A group of adult rats wascastrated and epididymides were removed three days following castration. The epididymides were dissected into caput,corpus and cauda segments, homogenized, and proteins were fractionated by anion exchange HPLC. Proteins in select-ed fractions were resolved by SDS-PAGE and visualized by silver staining. Results: It was observed that the levels ofmultiple proteins drastically reduced in the various regions of epididymis of the orchiectomized rats. Conclusion: Theepididymal proteins appear to be useful markers to study androgenic action in the epididymis.

关键词： epididymis proteins sperm maturation orchiectomy castration rats

Optimal placement of dampers and actuators based on stochastic approach

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Earthquake Engineering and Engineering Vibration 2002年第2期1卷 237-249页

作者： Franklin y.cheng Hongping Jiang Xiaozhe Zhang Department of Civil Engineering University of Missouri-RollaRollaMissouri 65409USA Technical Development Department Magnatrax Corporation124 Kirby DrivePortlandTN 37148USA

A general method is developed for optimal application of dampers and actuators by installing them at optimal location on seismic-resistant *** study includes development of a statistical criterion,formulation of a general optimization problem and establishment of a solution *** analysis of the seismic response in time-history of controlled structures is used to verify the proposed method for optimal device application and to demonstrate the effectiveness of seismic response control with optimal device *** study shows that the proposed method for the optimal device application is simple and general,and that the optimally applied dampers and actuators are very efficient for seismic response reduction.

关键词： optimal device placement dampers actuators seismic response control stochastic seismic response seismic-resistant structures equivalent modal analysis

A review of chatter vibration research in milling

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Chinese Journal of Aeronautics 2019年第2期32卷 215-242页

作者： Caixu yUE Haining GAO Xianli LIU steven y.LIANG Lihui WANG Harbin University of Science and Technology Georgia Institute of Technology KTH Royal Institute of Technology

Chatter is a self-excited vibration of parts in machining systems. It is widely present across a range of cutting processes, and has an impact upon both efficiency and quality in production processing. A great deal of research has been dedicated to the development of technologies that are able to predict and detect chatter. The purpose of these technologies is to facilitate the avoidance of chatter during cutting processes, which leads to better surface precision, higher productivity,and longer tool life. This paper summarizes the current state of the art in research regarding the problems of how to arrive at stable chatter prediction, chatter identification, and chatter control/-suppression, with a focus on milling processes. Particular focus is placed on the theoretical relationship between cutting chatter and process damping, tool runout, and gyroscopic effect, as well as the importance of this for chatter prediction. The paper concludes with some reflections regarding possible directions for future research in this field.

关键词： Chatter Gyroscopic effects Milling Process damping Tool runout

Microstructure and mechanical properties of TiAl/TiAl joints brazed with a newly developed Ti–Ni–Nb–Zr quaternary filler alloy

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Progress in Natural Science:Materials International 2022年第6期32卷 758-768页

作者： H.S.Ren y.L.Shang X.y.Ren y.J.Jing H.P.Xiong y.y.cheng Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials

A novel Ti-Ni-Nb-Zr quaternary filler alloy with the composition of Ti-(19～25)Ni-(15～25)(Nb+Zr)(wt.%) was *** filler alloy was composed of(Ti,Nb)ss,(Ti,Zr,Nb)ss+(Ti,Zr)2Ni,α-Ti and Ti2Ni *** was fabricated into filler foil with a thickness of about 45 μm by a rapid solidification *** results indicate that the liquidus temperature of the Ti-Ni-Nb-Zr brazing alloy was about 978℃,and the brazing alloy presented excellent wettability on TiAl *** TiAl joint mainly consisted of β/B2 phase,Ti2Al,Ti2AlNi and α2-Ti3Al *** diffusion of Al atom from base metal to brazed seam led to the formation of Ti2Al and *** that no previously references on XRD pattern of Ti2AlNi compound can be found,Ti2AlNi cast alloy specimen was specially prepared and XRD peaks were specially *** micro-hardness and bending strength tests of the Ti2AlNi phase were carried out,and the results were 761 HV and 192 MPa,*** brazing parameters of 1010 ℃/10 min offered the joint shear strength of 280 MPa at room temperature,and the joints exhibited tensile strength of 372 MPa at room temperature and 340 MPa at 750 ℃,indicating that the newly developed filler alloy could offer a stable high-temperature strength.

关键词： TiAl Brazing Filler alloy Microstructure Mechanical properties

Modeling and analysis of a catastrophic oil spill and vapor cloud explosion in a confined space upon oil pipeline leaking

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Petroleum Science 2020年第2期17卷 556-566页

作者： Shengzhu Zhang Xu Wang y.Frank cheng Jian Shuai China Academy of Safety Science and Technology Beijing 100012China Department of Mechanical Engineering University of CalgaryCalgaryAB T2N 1N4Canada College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

Oil spill-induced vapor cloud explosions in a confined space can cause catastrophic *** this work,investigation was conducted on the catastrophic pipeline leak,oil spill,and the resulting vapor cloud explosion accident occurring in China in 2013 by modeling analysis,field surveys,and numerical *** total amount of the spilled oil was up to2044.4 m3 due to improper *** long residence time of the oil remaining in a confined space permitted the formation of explosive mixtures and caused the vapor cloud explosion.A numerical model was developed to estimate the consequence of the explosion based on volatilization testing *** results show that the death-leading zone and the glass-breaking zone could be 18 m and 92 m,respectively,which are consistent with the field *** severity of the explosion is related to the amount of the oil spill,properties of oil,and volatilization *** is recommended that a comprehensive risk assessment be conducted to analyze the possible consequences upon oil spilling into a confined *** collection and ventilation measures should be taken immediately after the spill occurs to reduce the time for oil volatilization and prevent the mixture from reaching its explosive limit.

关键词： Pipeline leaking Oil spill Vapor cloud explosion Confined space Consequence analysis