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Journal of Beijing Institute of Technology 2019年第3期28卷 659-666页

作者： yu li Xuefei lü yuanzhan Yang yulin Deng School of life Science Beijing Institute of Technology

Detecting protein expression levels in organisms exposed to environmental pollutants can help us understand the action mechanism of toxicity. In the present study, adult female Sprague-Dawley (SD) rats received a consecutive intraperitoneal injection of tris(2,3-dibromopropyl) isocyanurate (TBC) for seven days, and the ^16O/^18O labeling comparative proteomic approach was used to study the change of liver proteome in these rats. Thirty six differential proteins were identified between the control group and the high-dose-exposed group (8 mg/kg), of which, twenty eight proteins were down-regulated and eight proteins were up-regulated. Bioinformatics analysis revealed that most of the differential proteins were related with the metabolic and cellular processes. In addition, the contents of malondialdehyde (MDA), catalase (CAT), and glutathione (GSH) in liver were measured to evaluate the oxidative stress status induced by TBC exposure. Together, these findings showed that TBC might be toxic to liver by disrupting metabolic process and apoptosis. The results might provide a better insight into the mechanism of toxicity induced by TBC.

关键词： comparative proteomic hepatotoxicity ^18O labeling oxidative stress tris(2,3-dibromopropyl) isocyanurate (TBC)

Recruitment of older adults into randomized controlled trials:Issues and lessons learned from two community-based exercise interventions in Shanghai

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Journal of Sport and Health Science 2016年第3期5卷 308-314页

作者： lingyan Huang Jiaojiao lü Nan Chen yu liu Key laboratory of Exercise and Health Sciences of Ministry of Education Shanghai University of Sport Department of Rehabilitation Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine

Background: With the increasing need for high-quality exercise interventions in China, relatively little is known about issues and challenges related to recruitment of older Chinese adults into exercise-based disease prevention interventions. This study aims to describe the recruitment process and outcomes of 2 exercise interventions conducted in Shanghai, ***: Recruitment information was ascertained from 2 community-based randomized controlled trials for 2 exercise interventions, the first designed to improve health outcomes for older women with knee osteoarthritis and the second to study changes in cognitive function in adults with mild cognitive impairment. Results were summarized in terms of recruitment sources, number screened, screening-to-enrollment ratios, and ***: Recruitment was primarily achieved through working with local residential divisions(i.e., neighborhood associations and residential committees). Both studies achieved their planned target number of older adults(45 and 46, respectively) within a 1-year time frame, with a screening-to-randomized ratio of 5:1 and demonstrated excellent retention rates(range 87%–93%) at 6 months. The recruitment cost for the 2studies averaged RMB 189(about USD 30) per initial recruit and RMB 738(about USD 119) per participant randomized. Some major issues encountered during the recruitment process included(1) the use of community neighborhoods to support the conduct of the projects,(2) access to participants, and(3) ***: Analysis of the 2 randomized controlled trials has provided valuable insights into the recruitment process and identified resources that can help better planning and recruitment for future interventions. Recommendations aimed at increasing the success of future recruitment efforts are provided.

关键词： Community stakeholders Exercise intervention Older adults Participant access Randomized controlled trial Recruitment

Applications for Nanoscale X-ray Imaging at High Pressure

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Engineering 2019年第3期5卷 479-489页

作者： Wendy l. Mao yu lin Yijin liu Jin liu Department of Geological Sciences Stanford University Stanford CA 94305 USA Stanford Institute for Materials and Energy Sciences SLAC National Accelerator Laboratory Menlo Park CA 94025 USA Stanford Synchrotron Radiation lightsource SLAC National Accelerator Laboratory Menlo Park CA 94025 USA

Coupling nanoscale transmission X-ray microscopy (nanoTXM) with a diamond anvil cell (DAC) has exciting potential as a powerful three-dimensional probe for non-destructive imaging at high spatial resolution of materials under extreme conditions. In this article, we discuss current developments in high-resolution X-ray imaging and its application in high-pressure nanoTXM experiments in a DAC with third-generation synchrotron X-ray sources, including technical considerations for preparing successful measurements. We then present results from a number of recent in situ high-pressure measurements investigating equations of state (EOS) in amorphous or poorly crystalline materials and in pressureinduced phase transitions and electronic changes. These results illustrate the potential this technique holds for addressing a wide range of research areas, ranging from condensed matter physics and solidstate chemistry to materials science and planetary interiors. Future directions for this exciting technique and opportunities to improve its capabilities for broader application in high-pressure science are discussed.

关键词： X-ray imaging High pressure Diamond anvil cell

Study on Top-Down Estimation Method of Software Project Planning

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 108-111页

作者： ZHANG Jun-guang lǖ Ting-jie ZHAO yu-mei School of Economics and Management Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

This paper studies a new software project planning method under some actual project data in order to make software project plans more effective. From the perspective of system theory, our new method regards a software project plan as an associative unit for study. During a top-down estimation of a software project, Program Evaluation and Review Technique （PERT） method and analogy method are combined to estimate its size, then effort estimation and specific schedules are obtained according to distributions of the phase effort. This allows a set of practical and feasible planning methods to be constructed. Actual data indicate that this set of methods can lead to effective software project planning.

关键词： planning top-down average productivity estimation method

The Potential Contribution of Subsurface Drip Irrigation to Water-Saving Agriculture in the Western USA

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Agricultural Sciences in China 2009年第7期8卷 850-854页

作者： T l Thompson PANG Huan-cheng lI yu-yi Department of Plant and Soil Science Texas Tech University Lubbock TX 79409 USA Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences (CAAS) Beijing 100081 P. R. China

Water shortages within the western USA are resulting in the adoption of water-saving agricultural practices within this region. Among the many possible methods for saving water in agriculture, the adoption of subsurface drip irrigation （SDI） provides a potential solution to the problem of low water use efficiency. Other advantages of SDI include reduced NO3 leaching compared to surface irrigation, higher yields, a dry soil surface for improved weed control, better crop health, and harvest flexibility for many specialty crops. The use of SDI also allows the virtual elimination of crop water stress, the ability to apply water and nutrients to the most active part of the root zone, protection of drip lines from damage due to cultivation and tillage, and the ability to irrigate with wastewater while preventing human contact. Yet, SDI is used only on a minority of cropland in the arid western USA. Reasons for the limited adoption of SDI include the high initial capital investment required, the need for intensive management, and the urbanization that is rapidly consuming farmland in parts of the western USA. The contributions of SDI to increasing yield, quality, and water use efficiency have been demonstrated. The two major barriers to SDI sustainability in arid regions are economics （i.e., paying for the SDI system）, including the high cost of installation; and salt accumulation, which requires periodic leaching, specialized tillage methods, or transplanting of seedlings rather than direct-seeding. We will review advances in irrigation management with SDI.

关键词： subsurface drip irrigation (SDI) water-saving agriculture western USA

Optomechanically induced transparency in a spinning resonator

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Photonics Research 2017年第4期5卷 367-371页

作者： HAO lü YAJING JIANG yu-ZHU WANG HUI JING Key laboratory for Quantum Optics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Physics Henan Normal University Key laboratory of low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University

We study optomechanically induced transparency in a spinning microresonator. We find that in the presence of rotation-induced Sagnac frequency shift, both the transmission rate and the group delay of the signal are strongly affected, leading to a Fano-like spectrum of transparency. In particular, tuning the rotary speed leads to the emergence of nonreciprocal optical sidebands. This indicates a promising new way to control hybrid light–sound devices with spinning resonators.

关键词： rate

Degradation patterns of silicone-based dielectric elastomers in electrical fields

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International Journal of Smart and Nano Materials 2018年第4期9卷 217-232,I0001页

作者： liyun yu Frederikke B.Madsen Anne l.Skov Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

Silicone elastomers have been heavily investigated as candidates for the flexible insulator material in dielectric elastomer transducers and are as such almost ideal candidates because of their inherent softness and ***,silicone elastomers suffer from low dielectric *** shortcoming has been attempted optimized through different approaches during recent *** optimization with the sole purpose of increasing the dielectric permittivity may lead to the introduction of problematic phenomena such as premature electrical breakdown due to high leakage currents of the thin elastomer *** this work,electrical breakdown phenomena of various types of permittivity-enhanced silicone elastomers are *** showed that different types of polymer backbone chemistries lead to differences in electrical breakdown patterns,which were revealed through SEM *** may pave the way towards a better understanding of electrical breakdown mechanisms of dielectric elastomers and potentially lead to materials with increased electrical breakdown strengths.

关键词： Silicone elastomers dielectric electrical breakdown voltage stabilization characterization

China＇s Sponge City construction： A discussion on technical approaches

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Frontiers of Environmental Science & Engineering 2017年第4期11卷 39-49页

作者： Haifeng Jia Zheng Wang Xiaoyue Zhen Mike Clar Shaw l. yu School of Environment Tsinghua University Beijing 100084 China Beijing Orient Tetra Tech Ecological Technology ltd. Beijing 100051 China Tetra Tech Fairfax VA 22030 USA Department of Civil & Environmental Engineering University of Virginia Charlottesville VA 22904 USA

Since 2014, China has been implementing the Sponge City Construction initiative, which represents an enormous and unprecedented effort by any government in the world for achieving urban sustainability. According to preliminary estimates, the total investment on the Sponge City Plan is roughly 100 to 150 million yuan （RMB）（$15 to $22.5 million） average per square kilometer or 10 Trillion yuan （RMB）（$1.5 Trillion） for the 657 cities nationwide. The Sponge City Plan （SCP） calls for the use of natural processes such as soil and vegetation as part of the urban runoff control strategy, which is similar to that of low impact development （lID） and green infrastructure （G1） practices being promoted in many parts of the world. The SCP includes as its goals not only effective urban flood control, but also rainwater harvest, water quality improvement and ecological restoration. So far, the SCP implementation has encountered-some barriers and challenges due to many factors. The present paper presents a review of those barriers and challenges, oftizrs discussions and recommendations on several technical aspects such as control goals and objectives; planning/design and construction of lID/GI practices; performance evaluation. Several key recommendations are proposed on Sponge City implementation strategy, Site-specific regulatory fi＇amework and technical gmdance, Product innovation and certification, lID/GI Project financing, lID/G1 profcssional training and certification, public outreach and education. It is expected that the successful implemen!atiun of the. SCP not only will bring about a sustainable, eco-friendly urbanization process in China, but also contribute enormously to the lID/Gl research and development with the vast amount of relevant data and experiences generated from the Sponge City construction projects.

关键词： low impact development Green infrastructure (GI) Sponge City Barriers Construction strategies

Estimating evapotranspiration from terrestrial groundwater-dependent ecosystems using landsat images

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International Journal of Digital Earth 2011年第2期4卷 154-170页

作者： Xihua Yang Peter l.Smith Tao yu Hailiang Gao Department of Environment Climate Change and WaterPO Box 3720ParramattaNSW 2124SydneyAustralia Institute of Remote Sensing Application Chinese Academy of SciencesBeijingChina

Understanding and mitigating against the impact of groundwater extraction on groundwater-dependent ecosystems(GDE)requires information of evapotranspiration(ET)of these *** this pilot study,we tested two remotesensing methods,Surface Energy Balance Algorithms for land(SEBAl)and Vegetation Index/Temperature Trapezoid(VITT),for ET estimation from terrestrial ***-temporal landsat Thematic Mapper(TM)and Enhanced Thematic Mapper(ETM)images were used to derive vegetation indices and land surface temperatures for ET *** transfer model was used for atmospheric correction of the landsat *** measurements were used to validate the remote sensing estimation of VI and surface *** methods have been implemented in a geographic information system(GIS)using automated scripts and ancillary GIS data for quality control *** of predicted ET by SEBAl to VITT model indicates relatively good agreement(R20.90)and promise for use in groundwater *** average ET from woodland GDEs within the zone of influence of the pumping stations is in general lower than similar woodlands outside of the pumping area,particularly in summer seasons which demonstrates that the pumping regime has an impact on those *** study also demonstrates that even a simple physical ET model can provide useful information for groundwater management,and more broadly other applications in hydrologic modelling and digital earth studies.

关键词： remote sensing evapotranspiration surface energy balance landsat groundwater-dependent ecosystems digital earth,GIS

Elastic-plastic behavior of a semicircular frame being pressed against a rigid plane

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Acta Mechanica Sinica 2008年第4期24卷 419-432页

作者： X.W.Zhang J.l.Yang T.X.yu Institute of Solid Mechanics Beihang University Beijing 100083 China Department of Mechanical Engineering Hong Kong University of Science and Technology Kowloon Hong Kong China

As a simplified structural model, a semicircular frame is used to study the crashworthiness behavior of an aircraft fuselage. The quasi-static large elastic-plastic deformation of a semicircular frame in the process of its being pressed against a rigid ground is analyzed. First, based on the linear elastic assumption, the quasi-static large deformation contact process of the frame can be divided into three phases, i.e., point contact, line contact and post-buckling. By means of a shooting method, the relations between the displacement and contact force as well as the distribution of bending moment in the three phases are obtained. Then, by assuming an elastic, perfectly-plastic moment-curvature relationship for the semi-circular frame, the contact process is analyzed in detail to reveal the plastic collapse mechanism, the traveling of plastic hinge and the force-displacement relationship. In order to verify the analysis, a preliminary experiment was conducted, in which two types of half rings with clamped ends were pressed by a rigid plate. In addition, a numerical simulation is also conducted by employing ABAQUS to analyze both rectangular cross-sectional beam and I-beam. Finally, the theoretical predictions are compared with the experimental results and numerical solutions, showing that the elastic-plastic analysis can predict the contact process very well.

关键词： Elastic-plastic·large deformation ·Semicircular frame Contact ·Traveling hinge