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Biological effect of human serum collected before and after oral intake of Pygeum africanum on various benign prostate cell cultures

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Asian Journal of Andrology 2012年第3期14卷 499-504,I0010页

作者： Stephane Larre Philippe Camparo Eva Comperat Delphine Boulbes Mohammed Haddoum Sylvain Baulande Pascal Soularue Pierre Costa Olivier Cussenot Nuffield Department of Surgical Science University of Oxford Oxford OX3 9DU UK er2 UMPC CeRePP Paris 75000 France Department of Pathology Val de Grace Hospital Paris 75000 France Department of Pathology La Pitie Salpetriere Hospital Paris 75000 France Laboratoire Solvay Pharma Paris 75000 France partnerChip Genople Evry 91000 France Department of Urology CHU Caremeau NTmes 30000 France

Pygeum africanum （Tadenan） is a popular phytotherapeutic agent used in the treatment of symptomatic benign prostatic hyperplasia. The active compounds of the drug have not been identified, and determining the plasma concentration of the drug is, therefore, not possible. Because there are conflicting results on the efficacy of this drug, we aimed to investigate its effect on prostate cell growth in vitro using human serum collected before and after Pygeum africanum intake. We used primary and organotypic cultures of human prostatic stromal myofibroblast cell line WPMY and prostatic epithelial cell line PNT2. We also used fresh benign prostatic tissue. The serum of a treated man induced decreases in the proliferation of primary cells, organotypic cells and WPMY cells but not PNT2 cells. We also analysed the effect of treated serum on the gene expression profile of WPMY cells. The transcriptome analysis revealed an upregulation of genes involved in multiple tumour suppression pathways and a downregulation of genes involved in inflammation and oxidative-stress pathways. The oral intake of Pygeum africanum resulted in serum levels of active substances that were sufficient to inhibit the proliferation of cultured myofibroblasts prostatic cells. This inhibition was associated with changes in the transcriptome. Asian Journal of Andrology（2012） 14, 499-504; doi：lO.1038/aja.2011.132; published online 26 December 2011

关键词： benign prostatic hyperplasia organotypic culture primary culture PNT2 Pygeum africanum transcriptome WPMY

A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties

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Neural Regeneration Research 2025年第7期20卷 2084-2094页

作者： Tong Li Quhan Cheng Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu Tang Zhongyang Liu Kai Wang Department of Orthopedics the Fourth Medical Center of Chinese PLA General HospitalBeijingChina Department of Training and Sports Medicine Characteristic Medical Center of Chinese People’s Armed Police ForceTianjinChina Medical School of Chinese PLA BeijingChina Key Laboratory of Bioactive Materials for the Ministry of Education College of Life SciencesNankai UniversityTianjinChina Department of Orthopedics Tianjin HospitalTianjinChina Department of Rehabilitation Medicine Er Quan Hospital of PAPWuxiJiangsu ProvinceChina

Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor *** an alternative,nerve guidance conduits may be *** ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve *** designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align ***,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber *** presence of aligned fibers on the inner surface can promote the extension of nerve cells along the *** helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide *** novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.

关键词： aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance

Paired Assistance:Policy Rationale and Economic Performance as Illustrated by Xizang and Xinjiang

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China Economist 2024年第3期19卷 70-88页

作者： Li Xihui Wang Guiduo Duan Pengfei Huang Jixin Minzu University of China BeijingChina Pu’er University Pu’erChina

This study highlights the changing priorities of China’s paired assistance throughout the past decades,as well as its theoretical implications and economic growth effects for recipient *** panel data from 32 prefecture-level cities from 1990 to 2020,this study uses the multiperiod difference-in-differences approach to examine how paired assistance has contributed to economic growth in Xizang Autonomous Region and Xinjiang Uygur Autonomous *** findings indicate that,first,the implementation of the paired assistance policy has boosted economic growth in Xizang and ***,paired assistance has stimulated economic growth in recipient communities by improving ***,paired assistance has contributed to economic growth in recipient communities by providing improved public services such as education and *** to public services have a relatively smaller indirect effect in short term than infrastructure development on economic *** both education and healthcare are crucial to people’s quality of life in recipient *** paper has refined and broadened research on the effects of paired assistance,providing preference for future policymaking.

关键词： Chinese characteristics paired assistance multiperiod difference-in-differences assessment of policy effects

Effect of concentration quenching on the spectroscopic properties of er^(3+)/Yb^(3+) co-doped AlF_3-based glasses

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Chinese Optics Letters 2004年第10期2卷 600-603页

作者：张军杰戴世勋徐时清汪国年张丽艳胡丽丽 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Science Shanghai 201800 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Science Shanghai 201800 series of highly Er~(3+)/Yb~(3+) co-doped fluoroaluminate glasses have been investigated in order to develop a microchip laser at 1.54 μm under 980 nm excitation. Measurements of absorption emission and upconversion spectra have been performed to examine the effect of Er~(3+)/Yb~(3+) concentration quenching on spectroscopic properties. In the glasses with Er~(3+) concentrations below 10 mol% concentration quenching is very low and the Er~(3+)/Yb~(3+) co-doped fluoroaluminate glasses have stronger fluorescence of 1.54μm due to the ~4I_(13/2)→~4I_(15/2) transition than that of Er~(3+) singly-doped glasses. As Er~(3+) concentrations above 10 mol% in the Er~(3+)/Yb~(3+) co-doped samples concentration quenching of 1.54μm does obviously occur as a result of the back energy transfer from Er~(3+) to Yb~(3+). To obtain the highest emission efficiency at 1.54μm the optimum doping-concentration ratio of Er~(3+)/Yb~(3+) was found to be approximately 1:1 in mol fraction when the Er~(3+) concentration is less than 10 mol%.

A series of highly er^(3+)/Yb^(3+) co-doped fluoroaluminate glasses have been investigated in order to develop a microchip laser at 1.54 μm under 980 nm excitation. Measurements of absorption, emission and upconversion spectra have been performed to examine the effect of er^(3+)/Yb^(3+) concentration quenching on spectroscopic properties. In the glasses with er^(3+) concentrations below 10 mol%, concentration quenching is very low and the er^(3+)/Yb^(3+) co-doped fluoroaluminate glasses have stronger fluorescence of 1.54μm due to the ~4I_(13/2)→~4I_(15/2) transition than that of er^(3+) singly-doped glasses. As er^(3+) concentrations above 10 mol% in the er^(3+)/Yb^(3+) co-doped samples, concentration quenching of 1.54μm does obviously occur as a result of the back energy transfer from er^(3+) to Yb^(3+). To obtain the highest emission efficiency at 1.54μm, the optimum doping-concentration ratio of er^(3+)/Yb^(3+) was found to be approximately 1:1 in mol fraction when the er^(3+) concentration is less than 10 mol%.

关键词： Yb co-doped AlF3-based glasses Effect of concentration quenching on the spectroscopic properties of er

Harvesting net power and desalinating water by pressure-retarded membrane distillation

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Science China(Technological Sciences) 2022年第1期65卷 214-220页

作者： ZHAO RunZe LI Ji ZHANG ZiKang LONG Rui LIU Wei LIU ZhiChun School of Energy and Pow er Engineering Huazhong University of Science and TechnologyWuhan 430074China

Pressure-retarded membrane distillation(PRMD)can convert low-grade heat to useful work by harvesting the pressure energy of the condensation liquid on the cold *** this study,a new type of PRMD system for combined freshwater and power production was *** this configuration,the thermal energy of the phase change is transported to the interface mainly by conduction rather than convection,which significantly reduces the pump power loss of the liquid *** addition,it also utilizes a multistage structure to regenerate heat with low pump power *** experimental results showed that,for a module with a heating area of 1.0 m^(2),this system can produce 188 L of freshwater and 27.8 kJ of power each day when operating between 80℃ and 40℃.The water and power densities of the PRMD configuration would be affected by saline ions in the feed liquid,air resistance in the evaporation chamber,membrane wetting,and membrane *** experimental and molecular dynamics simulation results indicated that a higher temperature difference or working temperature will significantly improve the desalination and power generation rates because of the increased mass transfer driving force of the vapor *** study proved that it is possible for a PRMD system to simultaneously obtain net power and freshwater using low-grade heat as the only energy ***,the liquid supply,working pressure,and membrane properties should be improved to achieve better performance.

关键词： desalination renewable energy low-grade heat thermo-osmosis membrane distillation

Optimal Data Placement and Replication Approach for SIoT with Edge

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Computer Systems Science & Engineering 2022年第5期41卷 661-676页

作者： B.Prabhu Shankar S.Chitra Department of Information Technology Er Perumal Manimekalai College of EngineeringHosur635117TamilnaduIndia Department of Computer Science and Engineering Er Perumal Manimekalai College of EngineeringHosur63117TamilnaduIndia

Social networks(SNs)are sources with extreme number of users around the world who are all sharing data like images,audio,and video to their friends using IoT *** concept is the so-called Social Internet of Things(SIot).The evolving nature of edge-cloud computing has enabled storage of a large volume of data from various sources,and this task demands an efficient storage *** this kind of large volume of data storage,the usage of data replication using edge with geo-distributed cloud service area is suited to fulfill the user’s expectations with low *** major issue is the way to store the data and replicate these large data items optimally and allocate the request from the data center *** efficient storage of these data,we use edge server,which is part of the cloud server,in this ***,the data are distributed and stored with quick access,which will reduce the latency with *** proposed data placement approach learns with machine learning(ML)algorithm called radial basis kernel function assisted with support vector machine(RBF-SVM)to classify the data center for storing the user and friend’s data from the SIoT *** learning algorithms will be used to predict the workload of the data stored in the data center as either edge or cloud depending on the existing time *** data placement with dynamic nature is also optimized using the proposed dynamic graph partitioning(GP)method to meet the individual user’s demand of low latency with minimum *** way will keep the SIoT data placement efficient and effective over ***,this proposed data placement and replication approach introduces three kinds of innovations compared with the existing data placement approach.(i)Rather than storing the user data in a single cloud,this study uses the edge server closest to the SIoT devices for faster access with reduced response time.(ii)The classification algorithm called RBF-SVM is used to find storage for

关键词： Data placement data replication social network social internet of things edge computing cloud computing graph partitioning support vector machine machine learning radial basis function latency storage cost

Control System Design for Low PowerMagnetic Bearings in a Flywheel Energy Storage System

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Energy Engineering 2023年第1期120卷 147-161页

作者： Tinnawat Hongphan Matthew O.T.Cole Chakkapong Chamroon Ziv Brand Department of Mechanical Engineering Chiang Mai UniversityChiang Mai50200Thailand 2Department of Mechanical EngineeringShamoon College of EngineeringBe’er Sheva84100Israel

This paper presents a theoretical and experimental study on controller design for the AMBs in a small-scale flywheel energy storage system,where the main goals are to achieve low energy consumption and improved rotordynamic stability.A H-infinity optimal control synthesis procedure is defined for the permanent-magnet-biased AMB-rotor system with 4 degrees of *** the choice of design weighting functions,notch filter characteristics are incorporated within the controller to reduce AMB current components caused by rotor vibration at the synchronous frequency and higher *** tests are used to validate the controller design methodology and provide comparative results on performance and *** results show that the H-infinity controller is able to achieve stable rotor levitation and reduce AMB power consumption by more than 40%(from 4.80 to 2.64 Watts)compared with the conventional PD control ***,the H-infinity controller can prevent vibrational instability of the rotor nutation mode,which is prone to occur when operating with high rotational speeds.

关键词： Magnetic bearings flywheel control systems gyroscopic effects stability efficiency

Delay-dependent robust control for uncertain stochastic systems with Markovian switching and multiple delays

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Journal of Systems Engineering and Electronics 2010年第2期21卷 287-295页

作者： Xudong zhao Mingxiang Ling Qingshuang Zeng Space Control and Inertial Technology Institute Harbin Institute of Technology Harbin 150001 ER. China

The exponential stability in mean square and stabiliza- tion problems for It＆ stochastic switched systems with multiple time-delays are investigated. The system possesses the norm- bounded uncertainties and Markovian jumping parameters. By using an effective descriptor model transformation of the system and applying Ito＇s differential formula and Moon＇s inequality for bounding cross terms, a new delay-dependent sufficient condi- tion is derived in terms of linear matrix inequalities, and its states feedback controller is designed. Numerical examples are given to illustrate the efficiency and less conservation of the results.

关键词： stochastic systems Markovian jump time-delays lin- ear matrix inequalities.

Surface-emitting lasers meet metasurfaces

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Light(Science & Applications) 2024年第2期13卷 172-174页

作者： Nir Shitrit School of Electrical and Computer Engineering Ben-Gurion University of the NegevBe’er Sheva8410501Israel

The integration between vertical-cavity surface-emitting lasers and metasurfaces has been demonstrated to enable on-chip high-angle illumination for total internal reflection and dark-field microscopy. Such an ultracompact combined laser-beam shaper system provides a versatile illumination module for high-contrast imaging, thus leveraging biophotonics and lab-on-a-chip devices and facilitating life-science applications.

关键词： lasers emitting illumination