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Follicle-stimulating hormone as a predictor for sperm retrieval rate in patients with nonobstructive azoospermia, a systematic review and meta-analysis

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Asian Journal of Andrology 2015年第2期17卷 281-284,I0010页

作者： Qi Yang Yan-Ping Huang Hong-Xiang Wang Kai Hu yi-Xin Wang yi-Ran Huang bin chen Department of Urology Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai institute of Andrology Shanghai 200127 China.

Noninvasive parameters for predicating sperm retrieval rate （SRR） are desirables. Follicle-stimulating hormone （FSH） has been an important predictor since the first years of testicular sperm extraction. Recent studies showed continuous interests in FSH, with both pros and cons. Thus, we conducted a meta-analysis to evaluate the diagnostic value of FSH as a predictor for patients with nonobstructive azoospermia （NOA） taking testicular sperm retrieval. Eligible diagnosis tests were identified from electronic databases （Cochrane Central Register of Controlled Trials, Medline, and EMBASE） without language restrictions. The database search, quality assessment, and data extraction were performed independently by two reviewers. The reference standard was the sperm retrieval result. Diagnostic value of FSH were explored by area under receiver operation characteristics （ROC） curve using Review Manager, version 5.1.0 （Cochrane Collaboration, Oxford, UK） and Meta-DiSc, version 1.4. Meta regression will be done if there is heterogeneity. Then, we find 11 tests including a total of 1350 patients met the inclusion criteria. Our pooled analysis showed that the area under ROC curve of FSH was 0.72 ~ 0.04. Meta regression analyses showed that region and average age have an influence on the diagnostic value. FSH showed more diagnostic value with patients in East Asia and with younger patients. We concluded that FSH had moderate value in independently predicating SRR in men with NOA （area under curve 〉0.7）. More detailed diagnosis tests should be anticipated in the future to confirm the diagnostic value of other noninvasive parameters.

关键词： follicule-stimulating hormone meta-analysis nonobstructive azoospermia testicular sperm retrieval

Churning loss characteristics of a wet three-phase high-speed reluctance motor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 251-267页

作者： Zhenzhou ZHANG Mingzhu DAI chenchen ZHANG yi chen bin MENG College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China

With the increasing requirements of electro-hydrostatic actuators(EHAs)for power,volume,and pressure,there is a growing tendency in the industry to combine the motor and pump to form a so-called'motor pump'to improve the *** this paper,a novel structure for a wet three-phase high-speed reluctance motor pump is proposed,which can further improve integration by removing the dynamic seal on the pump shaft,thereby avoiding the problems of dynamic seal wear and oil leakage and improving heat dissipation under high-speed working ***,after the motor is wetted,the churning loss caused by immersion of the rotor in the oil causes additional fluid resistance *** on fundamental fluid mechanics,an analytical model of the churning torque of a wet motor was *** verify the accuracy of the analytical model,a simulation model of churning loss was established based on computational fluid dynamics(CFD),and the churning torque and flow field state were ***,an experimental prototype was designed and manufactured,and a test bench for churning loss was *** oil churning torque was measured at different speeds and *** results from the analytical,simulation,and experimental models agreed *** experimental results validated the analytical model and CFD *** research provides a practical method for calculating the churning loss and serves as guidance for future optimization of churning loss reduction.

关键词： Motor pump Wet motor Churning loss Analytical model Computational fluid dynamics(CFD)

Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation

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Nuclear Science and Techniques 2024年第5期35卷 99-108页

作者： You-Ming Deng Yong-bin Leng Xing-yi Xu Jian chen yi-Mei Zhou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of the Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle *** is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter ***,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this *** with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed *** basic principles of the method,simulation,and experimental comparison are also *** on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal *** results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed.

关键词： Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF

Evaluation of frictional pressure drop correlations for air-water and air-oil two-phase flow in pipeline-riser system

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Petroleum Science 2024年第2期21卷 1305-1319页

作者： Nai-Liang Li bin chen School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049ShaanxiChina

Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop.

关键词： Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging Correlation

Controllable chemical redox reactions to couple microbial degradation for organic contaminated sites remediation:A review

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Journal of Environmental Sciences 2024年第5期139卷 428-445页

作者： bin chen Jiang Xu Lizhong Zhu College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control Zhejiang UniversityHangzhou 310058China Zhejiang Agriculture&Forest University Lin'an 311300China

Global environmental concern over organic contaminated sites has been progressively conspicuous during the process of urbanization and industrial *** traditional physical or chemical remediation technologies may significantly destroy the soil structure and function,coupling moderate chemical degradation with microbial remediation becomes a potential way for the green,economic,and efficient remediation of contaminated ***,this work systematically elucidates why and how to couple chemical technology with microbial remediation,mainly focused on the controllable redox reactions of organic *** rational design of materials structure,selective generation of reactive oxygen species,and estimation of degradation pathway are described for chemical ***,current progress on efficient and selective reductions of organic contaminants(i.e.,dechlorination,defluorination,-NO_(2) reduction)is *** with the microbial remediation of contaminated sites,several consideration factors of how to couple chemical and microbial remediation are proposed based on both fundamental and practical points of *** review will advance the understanding and development of chemical-microbial coupled remediation for organic contaminated sites.

关键词： Soil remediation Groundwater remediation Rational design Reactive species Environmental nanotechnology

Tuning mechanical behaviors of highly entangled hydrogels with the random distribution of mobile entanglements

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 277-294页

作者： Jinlong LIU Di LU bin chen Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China Beijing System Design Institute of Electro-Mechanic Engineering Beijing 100854China Intelligent Robotic Research Center Zhejiang LaboratoryHangzhou 310027China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Hangzhou 311100China

Highly entangled hydrogels exhibit excellent mechanical properties,including high toughness,high stretchability,and low *** considering the evolution of randomly distributed entanglements within the polymer network upon mechanical stretches,we develop a constitutive theory to describe the large stretch behaviors of these *** the theory,we utilize a representative volume element(RVE)in the shape of a cube,within which there exists an averaged chain segment along each edge and a mobile entanglement at each *** employing an explicit method,we decouple the elasticity of the hydrogels from the sliding motion of their entanglements,and derive the stress-stretch relations for these *** present theoretical analysis is in agreement with experiment,and highlights the significant influence of the entanglement distribution within the hydrogels on their *** also implement the present developed constitutive theory into a commercial finite element software,and the subsequent simulations demonstrate that the exact distribution of entanglements strongly affects the mechanical behaviors of the structures of these ***,the present theory provides valuable insights into the deformation mechanism of highly entangled hydrogels,and can aid in the design of these hydrogels with enhanced performance.

关键词： highly entangled hydrogel constitutive theory entanglement gamma distribution

Plasmon-enhanced self-powered GaN/ZnTe core/shell nanopillar array photodetector

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Nano Research 2024年第6期17卷 5569-5577页

作者： Jianqi Dong Dongqi Zhang yi Ma Daotong You Jinping chen bin Liu Xingfu Wang Zengliang Shi Chunxiang Xu State Key Laboratory of Digital Medical Engineering School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials National Laboratory of Solid State MicrostructuresSchool of Electronic Science and EngineeringNanjing UniversityNanjing 210093China Institute of Photonics Technology Jinan UniversityGuangzhou 510632China Guangdong Engineering Research Center of Optoelectronic Functional Materials and Devices Institute of SemiconductorsSouth China Normal UniversityGuangzhou 510631China

Nanostructure photodetectors,as the core component of optoelectronic devices,are mainly focused on the precise preparation of mixed-component nano-heterostructures and the realization of zero power consumption ***,we successfully fabricated n-GaN/p-ZnTe core/shell nanopillar array and realized self-power ultraviolet/violet *** radial heterojunction nanodevice reveals high light-dark current ratio of 104 at 0 V bias,indicating effective carriers’*** more,by integrating plasmonic effect,the responsivity and detectivity of the Au nanoparticles decorated device are increased from 3.85 to 148.83 mA/W and 4.45×1011 to 2.33×1012 Jones under 325 nm UV light *** the rise and the fall time are decreased 1.3 times and 6.8 times under 520 nm visible light irradiation at 0 V *** high photocurrent gain is derived from that the oscillating high-energy hot electrons in Au nanoparticles spontaneously inject into the ZnTe conduction band to involve the photodetection *** work presents an effective route to prepare high-performance self-power photodetector and provides a promising blueprint to realize different functional photoelectronic devices based on core/shell nanostructure.

关键词： GaN/ZnTe core/shell nanopillar array self-power ultraviolet/visible photodetector plasmonic effect

Liquid-metals-induced formation of MXene/polyacrylamide composite organohydrogels for wearable flexible electronics

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Nano Research 2024年第3期17卷 1913-1922页

作者： Minying Wu bin chen Xueliang Fan Tong Ye Yuanyuan Fang Qian Zhang Fangzhou Zhou Yajun Wang yi Tang Department of Chemistry Fudan UniversityShanghai 200433China College of Chemistry&Materials Engineering Wenzhou UniversityWenzhou 325027China

Organohydrogels have demonstrated superior environmental adaptability and frost resistance compared to conventional hydrogels,thereby prompting considerable interests in the development and design of innovative ***,we report an effective one-pot method for fabricating MXene/polyacrylamide(MXene/PAM)composite organohydrogel(MAOH)by employing Ga liquid metals(Ga LMs)as a highly reactive component in the induced free radical polymerization reaction,without the need for additional heating or cross-linking *** synthetic protocol addresses the time-consuming and organic solvent waste concerns associated with traditional solvent displacement methods for organohydrogel *** incorporation of MXene not only highly enhances the conductivity but also confers improved mechanical properties of *** MAOH exhibits excellent environmental adaptability(>7 d),sustained moisture retention,remarkable self-healing capabilities,and outstanding mechanical properties under low temperatures(-20℃).It demonstrates exceptional performance in micro-motion monitoring,rapid response time(125 ms),superior stretchability,and a broad range of strains(0.3%–600%).Therefore,the designed MAOH has great potential for applications in diverse fields such as prosthetics,electronic skin,human–machine interaction,and smart terminals.

关键词： organohydrogels MXene conductivity mechanical properties environmental adaptability

FPGA-based position reconstruction method for neutron beam flux spatial distribution measurement in BNCT

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Nuclear Science and Techniques 2024年第3期35卷 96-108页

作者： Wei Jiang Ping Cao yi-Ming Wu Xian-Ke Liu Zhu-Jun Fang Zhi-Yong Zhang bin Shi Jun chen State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China National Key Laboratory for Metrology and Calibration Techniques China Institute of Atomic EnergyBeijing 102413China

A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas *** address the issue of long processing times in traditional offline position reconstruction methods,this paper proposes a field programmable gate array based online position reconstruction method utilizing the micro-time projection chamber *** method encapsulates key technical aspects:a self-adaptive serial link technique built upon the dynamical adjustment of the delay chain length,fast sorting,a coordinate-matching technique based on the mapping between signal timestamps and random access memory(RAM)addresses,and a precise start point-merging technique utilizing a circular combined *** performance test of the selfadaptive serial link shows that the bit error rate of the link is better than 10-12 at a confidence level of 99%,ensuring reliable data *** experiment utilizing the readout electronics and Micromegas detector shows a spatial resolution of approximately 1.4 mm,surpassing the current method’s resolution level of 5 *** beam experiment confirms that the readout electronics system can obtain the flux spatial distribution of neutron beams online,thus validating the feasibility of the position reconstruction *** online position reconstruction method avoids traditional methods,such as bubble sorting and traversal searching,simplifies the design of the logic firmware,and reduces the time complexity from O(n2)to O(n).This study contributes to the advancement in measuring neutron beam flux for BNCT.

关键词： Position reconstruction FPGA Readout electronics Neutron flux spatial distribution