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Riemann-Hilbert Problem and Multiple High-order Poles Solutions of the Focusing mKdV Equation with Nonzero Boundary Conditions
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作者 Zi-yi WANG Shou-fu TIAN Jin-jie YANG 《Acta Mathematicae Applicatae Sinica》 2025年第1期234-251,共18页
The focusing modified Korteweg-de Vries(mKdV)equation with multiple high-order poles under the nonzero boundary conditions is first investigated via developing a Riemann-Hilbert(RH)approach.We begin with the asymptoti... The focusing modified Korteweg-de Vries(mKdV)equation with multiple high-order poles under the nonzero boundary conditions is first investigated via developing a Riemann-Hilbert(RH)approach.We begin with the asymptotic property,symmetry and analyticity of the Jost solutions,and successfully construct the RH problem of the focusing mKdV equation.We solve the RH problem when 1/S_(11)(k)has a single highorder pole and multiple high-order poles.Furthermore,we derive the soliton solutions of the focusing mKdV equation which corresponding with a single high-order pole and multiple high-order poles,respectively.Finally,the dynamics of one-and two-soliton solutions are graphically discussed. 展开更多
关键词 Riemann-Hilbert approach focusing mKdV equation nonzero boundary conditions multiple high-order poles soliton solutions
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具有POLE致病性突变子宫内膜癌的临床病理及分子特征分析
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作者 蔡宇梦 周杨 +4 位作者 汪昊 庞钧译 吴焕文 师晓华 梁智勇 《诊断病理学杂志》 2024年第4期282-286,322,共6页
目的探讨具有POLE致病性突变子宫内膜癌(EC)的临床病理及分子特征。方法选取179例EC患者,根据POLE基因突变、错配修复(MMR)蛋白表达及p53表达/TP53突变进行分子分型,分析POLE mut型EC的临床病理及分子特征。结果POLE mut20例,MMRd 48例,... 目的探讨具有POLE致病性突变子宫内膜癌(EC)的临床病理及分子特征。方法选取179例EC患者,根据POLE基因突变、错配修复(MMR)蛋白表达及p53表达/TP53突变进行分子分型,分析POLE mut型EC的临床病理及分子特征。结果POLE mut20例,MMRd 48例,NSMP 90例,p53 abn 21例。POLE mut EC多为FIGOⅠ期(17/20),中-低分化子宫内膜样癌(EEC)(13/20)、局限于内膜/浅肌层(17/20)、肿瘤浸润性淋巴细胞(TILs)显著(17/20)、无/局灶(LVSI)(18/20)、无淋巴结转移(19/20)。4个亚组间临床病理特征的差异均有统计学意义(P<0.05)。POLE mut型预后最好,具有多重分类特征的病例预后更接近POLE mut型。结论POLE mut EC提示着较高的组织学分级,较早的临床分期及较好的预后;POLE mut可继发dMMR/MSI-H表型及p53/TP53异常,应归类为POLE mut型。 展开更多
关键词 子宫内膜癌 分子分型 pole 错配修复缺陷 TP53
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Design and Evaluation of a Consequent Pole K-shaped Permanent Magnet Motor for Outboard Application Using a Hybrid Mathematical Model
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作者 Mehrage Ghods Jawad Faiz Hamed Gorginpour 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第4期379-393,共15页
Nowadays,there is considerable research interest in proposing modern permanent magnet(PM)electric machine structures for applications such as electric vehicles.Several radial and axial topologies with different arrang... Nowadays,there is considerable research interest in proposing modern permanent magnet(PM)electric machine structures for applications such as electric vehicles.Several radial and axial topologies with different arrangements of PM in the stator and rotor have been introduced for PM Vernier motors(PMVM)with the aim of increasing the performance characteristics such as power factor,efficiency,rotational torque torque density and wider constant torque-speed region.Meanwhile,the spoke PM arrangement has provided higher torque density than the surface and V-shaped arrangement.But in contrast,the V-shaped arrangement has a more sinusoidal flux and less cogging torque.In this paper,a 620 W,12-slot 16-pole Vernier PM motor with a fractional slot arrangement.Consequent K-shaped pole is introduced,which has the advantages of spoke and V-shaped magnetic arrangements.After presenting and confirming the concept of the proposed structure based on functional comparison with conventional structures,an analytical modeling based on the harmonic analysis method is introduced to accurately predict the performance of the machine,and finally the proposed structure is prototyped and the experimental results are simulated and modeling are compared. 展开更多
关键词 Non-linear harmonic model Conformal mapping Magnetic saturation Consequent pole K-shaped Vernier PM Machine Flux-modulation effects
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Effectiveness of Chromated Copper Arsenate against Deteriorating Agents of Eucalyptus Poles and Posts in Four Eco-Regions in Kenya
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作者 Miriam Gathogo Evanson Omuse George Muthike 《Open Journal of Forestry》 2024年第3期281-296,共16页
Previous studies done elsewhere have shown that Eucalyptus poles treated with chromated copper arsenate (CCA) can last over 30 years. Kenya is exceptional because in some eco-regions, the Eucalyptus poles’ life span ... Previous studies done elsewhere have shown that Eucalyptus poles treated with chromated copper arsenate (CCA) can last over 30 years. Kenya is exceptional because in some eco-regions, the Eucalyptus poles’ life span has greatly reduced to 5 years. The current study was designed to evaluate wood deteriorating agents of CCA-treated Eucalyptus poles and variability in four eco-regions of Kenya, namely, dryland, coastal, highland and humid lake. A total of 360 Eucalyptus pole samples were used for this experiment. Three CCA treatments were used to treat transmission poles at 20 kg/cm3 fencing posts samples at 6 kg/cm3, and a control group. Results indicated that termites and wood-decay fungi attacks caused wood deterioration in the four eco-regions. The proportion of power transmission pole degradation by wood deteriorating agents varied across eco-regions, between treatments and control and between time after treatments. Dryland eco-regions had the highest termite-related degradation (41.82%) while wood-decay fungi attack was highest in the highland eco-regions (9.20%). Samples treated with 6 kg/cm3 recorded the lowest level of wood deterioration, manifested by minimal superficial termite and wood-decay fungi attack. Samples treated with 20 kg/cm3 were characterized by moderate termite and wood-decay fungi attacks observed around the heartwood region, unlike sapwood. This study concluded that the deterioration of Eucalyptus CCA-treated poles is a question of climatic variability and hence, to increase the poles’ lifespan, CCA treatment should be tailored according to the characteristics of the ecoregion of use. Further investigations will inform the diversity of termites and decay-fungi across different eco-regions. 展开更多
关键词 Wood Deteriorating Agents CCA Transmission poles Wood-Decay Fungi
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Study on the Effect of Magnetic Pole Clipping Angle on the Eddy Current Loss of Permanent Magnets in the Rotor of Magnetically Levitated Permanent Magnet Synchronous High-Speed Electric Spindles
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作者 Xiangjun Shen Houcai Liu +2 位作者 Huimin Kang Ruirong He Jiale Xi 《Open Journal of Applied Sciences》 2024年第11期3261-3281,共21页
Aiming at the problem of high temperature and even demagnetization failure of permanent magnet (PM) due to PM eddy current loss in PM synchronous high-speed motors, this paper proposes a technique to lessen PM eddy cu... Aiming at the problem of high temperature and even demagnetization failure of permanent magnet (PM) due to PM eddy current loss in PM synchronous high-speed motors, this paper proposes a technique to lessen PM eddy current loss by cutting the angle of PM poles to change the shape of PM structure. Firstly, an analysis is conducted on the mechanism of PM synchronous high-speed motor eddy current loss production, the theoretical analytical model of PM eddy current loss is deduced, and it is theoretically proved that the magnetic pole shaving angle can reduce PM eddy current loss. Then, a 25 KW surface-type PM synchronous high-speed motor as an object, using two-dimensional time-step finite element method (FEM) to model and analyze PM eddy current loss. The results show that the smaller the PM pole shaving angle, the less its eddy current loss will be, it is possible to minimize the pole shaving angle of eddy current loss by 9.8% compared to the unshaved angle. Finally, the temperature field of the PM is calculated using a finite element method, and the outcomes demonstrate that the maximum temperature of the PM with a magnetic pole shaving angle can be reduced by about 5% compared with the unshaved angle. 展开更多
关键词 Magnetic pole Clipping Permanent Magnet (PM) Eddy Current Loss Temperature Field Two-Dimensional Time-Stepped Finite Element Method (FEM)
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Research on the Mechanical Analysis of Run-Up Speed in Pole Vaulting and the Application of Key Auxiliary Training Methods
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作者 Qin Xia 《Journal of Educational Theory and Management》 2024年第4期82-86,共5页
Analyzing from the perspective of physics mechanics,the pole vault is a project which transforms kinetic energy into elastic potential energy.The magnitude of kinetic energy depends on the vaulter’s approaching speed... Analyzing from the perspective of physics mechanics,the pole vault is a project which transforms kinetic energy into elastic potential energy.The magnitude of kinetic energy depends on the vaulter’s approaching speed,while the magnitude of elastic potential energy depends on height.Therefore,the run-up speed determines the vaulter’s performance in pole vault to a certain extent.the horizontal speed of the pole-holding approach phase transitioning into vertical upward speed plays a crucial role in executing pole vault techniques,and the model of approaching speed establishes a theoretical foundation for vaulters to break through the pole limitation.In terms of specialized technical assistance in speed training,short-distance speed exercises are used in the approaching phase;in the swinging phase,gymnastic rings,single bar and suspension rope exercises are employed for suspension;in the stretch phase,trampoline exercises play a important role in rotation phase,etc. 展开更多
关键词 pole vault techniques Run-up speed model Training techniques
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Reducing Greenhouse Gas Emissions through Improving the Life Span of Wooden Power Electric Poles of Eucalyptus saligna
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作者 Joseph Voufo Zakari Yaou +3 位作者 Florent Biyeme Rolland Djomi Richard Dadji Metangmo Théodore Tchotang 《Modern Mechanical Engineering》 2022年第1期1-26,共26页
The present work deals with reducing greenhouse gas emissions through improving the life span of wooden power electric poles of Eucalyptus saligna. Indeed, in Sub-Saharan African countries, Cameroon in particular, mos... The present work deals with reducing greenhouse gas emissions through improving the life span of wooden power electric poles of Eucalyptus saligna. Indeed, in Sub-Saharan African countries, Cameroon in particular, most of the power line networks are made of wooden supports and according to the Cameroon energy distribution company, wooden poles represent 32% of the causes of death linked to the state of the network. The company’s 2019 annual report indicates that 40,000 wooden poles were in critical condition and should be replaced. A significant number of mechanical failures affecting these supports have been observed. For example, on the HVA/LV power line “D17 Nko- abang” in Yaoundé in Cameroon, less than three years old, 10 (ten) cases of poles falling and/or breaking, due to their mechanical loading, were observed over a period of fewer than nine months, causing an average service stoppage for more than 11 hours and affecting an average of 3280 customers. These incidents lead to questions about how the supports are dimensioned and what load capacities they are designed to support. The aim of this work is, therefore, to suggest a method of dimensioning wooden poles hence reducing green- house gas emissions due to the deforestation by reducing the number of woo- den poles at risk to be replaced on Cameroon’s electricity distribution network. And more specifically, to reduce the number of mechanical failures affecting the wooden supports observed by analyzing the current wooden supports with their loads and to make proposals for improving the actual dimensioning me- thods. From the study carried out, it appears that 449 out of 845 supports, i.e., 53% needed to be replaced or monitored because they support the nominal forces ranging from 85% to 150% of their admissible limit and proposals have been made to improve their dimensioning. 展开更多
关键词 Electrical Power Line Dimensioning Wooden pole Efforts on pole pole’s Height Method of Loading Overload Coefficients
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POLE突变在肿瘤发生发展中的作用 被引量:6
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作者 黄茜 张声 《临床与病理杂志》 2015年第12期2173-2179,共7页
POLE为DNA聚合酶的催化亚基,具有5'3'DNA聚合酶活性和3'→5'核酸外切酶活性,对DNA复制和校正具有重要作用。POLE突变将引起校正功能缺失,可能导致肿瘤发生。近年来,TCGA在多种肿瘤中检出POLE突变,POLE突变的肿瘤以其独... POLE为DNA聚合酶的催化亚基,具有5'3'DNA聚合酶活性和3'→5'核酸外切酶活性,对DNA复制和校正具有重要作用。POLE突变将引起校正功能缺失,可能导致肿瘤发生。近年来,TCGA在多种肿瘤中检出POLE突变,POLE突变的肿瘤以其独特超强突变分子表型及良好的预后成为近期研究热点。本文综述POLE的结构、功能及其突变在肿瘤发生发展中的作用的研究进展。 展开更多
关键词 pole 肿瘤 预后
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South Pole温度风速廓线的统计分析 被引量:1
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作者 汪平 吴晓庆 《大气与环境光学学报》 CAS 2013年第5期334-343,共10页
利用2008年South Pole的探空资料,通过大气温度和风速廓线,确定了South Pole地区冬季(6,7,8月)和夏季(12,1,2月)的大气边界层结构、边界层和对流层顶的高度。对近地面的温度、水汽压、风速和风向进行了统计分析。结果表明,South Pole大... 利用2008年South Pole的探空资料,通过大气温度和风速廓线,确定了South Pole地区冬季(6,7,8月)和夏季(12,1,2月)的大气边界层结构、边界层和对流层顶的高度。对近地面的温度、水汽压、风速和风向进行了统计分析。结果表明,South Pole大气边界层大多时候为稳定型,但在夏季也存在不稳定的情况,尤其在1月份较多;夏季夜晚的边界层平均高度为389 m,比白天的304 m大,冬季夜晚的边界层平均高度为591 m,大于夏季夜晚;夏季白天对流层顶平均高度比夜晚略大,分别为6172 m和5770m。South Pole高层大气理查森数的倒数基本都小于4,发生湍流的可能性很小。 展开更多
关键词 SOUTH pole 温度风速廓线 边界层顶 对流层顶
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Design and field measurement of a dipole magnet for a newly developed superconducting proton cyclotron beamline 被引量:1
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作者 Jun-Sheng Zhang Jin-Xing Zheng +3 位作者 Yun-Tao Song Wu-Quan Zhang Ming Li Xian-Hu Zeng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第9期214-221,共8页
The design, field quality optimization, multipole field analysis, and field measurement of a dipole for a newly developed superconducting proton cyclotron(SC200) beamline are presented in this paper. The maximum magne... The design, field quality optimization, multipole field analysis, and field measurement of a dipole for a newly developed superconducting proton cyclotron(SC200) beamline are presented in this paper. The maximum magnetic field of the dipole is 1.35 T; the bending radius is 1.6 m with a proton beam energy in the range of70–200 Me V. The magnetic field was calculated with 2 D and 3 D simulations, and measured with a Hall mapping system. The pole shim and end chamfer were optimized to improve the field quality. Based on the simulated results,the multipole field components in the good-field region were studied to evaluate the field quality. The results showed that the field quality is better than ± 5 × 10^(-4) at1.35 T with shimming and chamfering. For the transverse field homogeneity, the third-order(B3) and fifth-order(B5)components should be controlled with symmetrical shims.The second-order(B2) component was the main disturbance for the integral field homogeneity; it could be improved with an end chamfer. The magnet manufacturing and field measurement were performed in this project. The measurement results demonstrated that the magnetic design and field quality optimization of the 45° dipole magnet can achieve the desired high field quality and satisfy the physical requirements. 展开更多
关键词 Magnet FIELD quality pole shim End CHAMFER MULTIpole FIELD component
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Rugged Resonant Pole and Its Applications in Soft-Switching Converter
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作者 肖岚 严仰光 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期225-232,共8页
The soft switching operation principle and operation performance of rugged resonant pole (RRP) is given. The applications of RRP in soft switching DC DC converter and soft switching inverter are discussed in detail. R... The soft switching operation principle and operation performance of rugged resonant pole (RRP) is given. The applications of RRP in soft switching DC DC converter and soft switching inverter are discussed in detail. RRP can constitute buck boost soft switching DC DC converter and isolated soft switching DC DC converter with the automatic limitation performance of output power. Partial series resonant DC DC converter with RRP can realize the zero voltage/zero current switching of power devices. RR... 展开更多
关键词 rugged resonant pole soft switching DC DC converter INVERTER
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基于South Pole站和McMurdo站的极区电离层闪烁统计特性 被引量:2
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作者 李鹏辉 胡红桥 +2 位作者 方涵先 刘瑞源 杨升高 《极地研究》 CAS CSCD 2016年第1期19-24,共6页
利用South Pole和Mc Murdo两站2013年12月至2014年11月期间的电离层相位闪烁数据,统计分析了两站电离层相位闪烁发生率的周日分布和季节分布。统计结果表明,两站的相位闪烁发生率在季节分布上,春秋季明显大于夏冬季;在周日分布上呈双峰... 利用South Pole和Mc Murdo两站2013年12月至2014年11月期间的电离层相位闪烁数据,统计分析了两站电离层相位闪烁发生率的周日分布和季节分布。统计结果表明,两站的相位闪烁发生率在季节分布上,春秋季明显大于夏冬季;在周日分布上呈双峰结构。在磁中午附近和磁子夜后有较大的闪烁发生率。磁中午附近是因为极隙区的软电子沉降和电离层对流导致的电离层不均匀性,造成较强的无线电波闪烁;磁子夜附近闪烁增强可能是穿越极盖区的等离子体云破碎造成较大密度梯度导致。总体上说,Mc Murdo站的闪烁发生率高于South Pole站,这可能是因为它们所处的磁纬不同所致。 展开更多
关键词 SOUTH pole McMurdo站 极区电离层 相位 闪烁发生率
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Mach-Zehnder Electro-Optic Polymer Modulator with C orona Poled Core Layer 被引量:3
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作者 杨晓红 杜云 +1 位作者 石志文 吴荣汉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第8期971-974,共4页
A Mach-Zehnder(MZ) electro-optic(EO) modulator are real iz ed,with three optical layers as polymer materials.The functional layer is the co rona poled crosslinkable polyurethane.The ridge waveguide is fabricated by us... A Mach-Zehnder(MZ) electro-optic(EO) modulator are real iz ed,with three optical layers as polymer materials.The functional layer is the co rona poled crosslinkable polyurethane.The ridge waveguide is fabricated by using the spin-coating,poling,photolithography and oxygen reactive ion etching(RIE) techniques.The mode and the modulation properties of these devices are demonstra ted in a micron control system,while the light source works at the wavelength of 1 31 or 1 55 micron. 展开更多
关键词 poled polymer M Z waveguide electro-optic modulator
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Silver Swallow in the Air in North Pole——Successfully fly through North Pole of the China Eastern Airline
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《China's Foreign Trade》 2001年第7期26-27,共2页
关键词 Silver Swallow in the Air in North pole Successfully fly through North pole of the China Eastern Airline
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Pole基因在子宫内膜癌中的研究进展 被引量:2
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作者 王蒙蒙 张丽华 《诊断病理学杂志》 2021年第7期582-584,共3页
2013年美国癌症基因组图谱(TCGA)提出依据分子改变将子宫内膜癌分为Pole突变型,MSI(微卫星不稳定)高突变型,高拷贝数型,低拷贝数型。其中,pole基因突变型具有形态学高度恶性,但具有较好预后,对免疫抑制剂反应良好的临床病理特征,同时pol... 2013年美国癌症基因组图谱(TCGA)提出依据分子改变将子宫内膜癌分为Pole突变型,MSI(微卫星不稳定)高突变型,高拷贝数型,低拷贝数型。其中,pole基因突变型具有形态学高度恶性,但具有较好预后,对免疫抑制剂反应良好的临床病理特征,同时pole基因突变可能与合并多个基因突变的子宫内膜癌有关,因此认识和了解pole基因突变与子宫内膜癌的关系非常重要。另外,对于pole突变合并P53,或者错配修复蛋白基因突变以及P53和错配修复蛋白基因同时突变,或者三个基因同时发生突变时,pole基因与其他基因的相互作用本文将复习文献,对pole基因突变的子宫内膜癌中研究进展进行综述。 展开更多
关键词 pole基因 子宫内膜癌 分子分型
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Improvement of Electrochemical Machining Accuracy by Using Dual Pole Tool 被引量:10
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作者 ZHU Di, XU Hui-yu (Department of Mechanical Engineering, Nanjing University of Aeronaut ics & Astronautics, Nanjing 210016, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期118-,共1页
Electrochemical machining (ECM) is one of the best al ternatives for producing complex shapes in advanced materials used in aircraft a nd aerospace industries. However, the reduction of the stray material removal co n... Electrochemical machining (ECM) is one of the best al ternatives for producing complex shapes in advanced materials used in aircraft a nd aerospace industries. However, the reduction of the stray material removal co ntinues to be major challenges for industries in addressing accuracy improvement . This study presents a method of improving machining accuracy in ECM by using a dual pole tool with a metallic bush outside the insulated coating of a cathode tool. The bush is connected with anode and so the electric field at the side gap area is substantially weakened. The modeling and simulation indicate that the p ositive bush brings down the current density at the side gap area of the machine d hole and hence reduces the stray material removal there. It has been experimen tally observed that the machining accuracy and the process stability are signifi cantly improved. 展开更多
关键词 electrochemical machining dual pole tool accura cy
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Retrograde intrarenal surgery vs miniaturized percutaneous nephrolithotomy to treat lower pole renal stones 1.5-2.5 cm in diameter 被引量:7
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作者 Mao-Mao Li Hou-Meng Yang +2 位作者 Xiao-Ming Liu Hong-Gang Qi Guo-Bin Weng 《World Journal of Clinical Cases》 SCIE 2018年第15期931-935,共5页
AIM To compare the outcomes of retrograde intrarenal surgery(RIRS) and miniaturized percutaneous nephrolithotomy(mini-PCNL) in treating lower pole(LP) renal stones with a diameter of 1.5-2.5 cm.METHODS A total of 216 ... AIM To compare the outcomes of retrograde intrarenal surgery(RIRS) and miniaturized percutaneous nephrolithotomy(mini-PCNL) in treating lower pole(LP) renal stones with a diameter of 1.5-2.5 cm.METHODS A total of 216 patients who underwent mini-PCNL(n = 103) or RIRS n = 113) for LP stones with a diameter of 1.5-2.5 cm were enrolled between December 2015 and April 2017 at the Urology Department of Ningbo Urology and Nephrology Hospital.RESULTS Significant differences were found in the hospital stay(9.39 ± 4.01 vs 14.08 ± 5.26, P < 0.0001) and hospitalization costs(2624.5 ± 513.36 vs 3255.2 ± 976.5, P < 0.0001) between the RIRS and mini-PCNL groups. The mean operation time was not significantly different between the RIRS group(56.48 ± 24.77) and the mini-PCNL group(60.04 ± 30.38, P = 0.345). The stone-free rates at the first postoperative day(RIRS vs mini-PCNL: 90.2% vs 93.2%, P = 0.822) and the second month postoperatively(RIRS vs mini-PCNL: 93.8% vs 95.1%, P = 0.986) were not significantly different.CONCLUSION RIRS and mini-PCNL are both safe and effective methods for treating LP stones with a diameter of 1.5-2.5 cm. RIRS can be considered as an alternative to PCNL for the treatment for LP stones of 1.5-2.5 cm. 展开更多
关键词 RETROGRADE intrarenal surgery PERCUTANEOUS nephrolithotripsy LOWER pole kidney stones MINIATURIZED PERCUTANEOUS NEPHROLITHOTOMY
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Continuous-wave mid-infrared intracavity singly resonant optical parametric oscillator based on periodically poled lithium niobate 被引量:7
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作者 丁欣 张少敏 +3 位作者 马洪梅 庞明 姚建铨 李卓 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第1期211-216,共6页
This paper reports a continuous-wave (CW) mid-infrared intracavity singly resonant optical parametric oscillator based on periodically poled lithium niobate (PPLN) pumped by a diode-end-pumped CW Nd:YVO4 laser. C... This paper reports a continuous-wave (CW) mid-infrared intracavity singly resonant optical parametric oscillator based on periodically poled lithium niobate (PPLN) pumped by a diode-end-pumped CW Nd:YVO4 laser. Considering the thermal lens effects, it adopted an optical ballast lens and the near-concentric cavity for better operation. At the PPLN's grating period of 28.5 μm and the temperature of 140℃, the maximum idler output power of 155 mW at 3.86 μm has been achieved when the 808 nm pump power is 8.5 W, leading to an optical-to-optical conversion efficiency of 1.82%. 展开更多
关键词 CONTINUOUS-WAVE MID-INFRARED intracavity optical parametric oscillator periodically poled lithium niobate crystal
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中国汉族人群DNA聚合酶ε基因POLE1单核苷酸多态性与肺癌易感性的关系
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作者 范祖鹏 彭群新 +3 位作者 高歌 吴文婷 钱吉 陈红岩 《癌变.畸变.突变》 CAS CSCD 2010年第4期265-270,共6页
目的:探讨人类DNA聚合酶ε基因POLE1单核苷酸多态性(SNP)与肺癌易感性间的关系。方法:采用病例对照研究方法,选择经组织学确诊的肺癌患者462例,以及相同地区,性别年龄频数匹配的对照466例,针对经筛选的5个SNP进行基因型检测,通过统计分... 目的:探讨人类DNA聚合酶ε基因POLE1单核苷酸多态性(SNP)与肺癌易感性间的关系。方法:采用病例对照研究方法,选择经组织学确诊的肺癌患者462例,以及相同地区,性别年龄频数匹配的对照466例,针对经筛选的5个SNP进行基因型检测,通过统计分析研究基因频率与肺癌风险的关系,并探讨吸烟在其中的影响。结果:病例组rs5744738基因频率分布高于对照组(P<0.05)。A/A纯合变异携带人群的患肺癌风险显著降低(校正OR=0.47,95%CI:0.25~0.91)。在分层分析中,60岁以上人群患肺癌的风险显著下降(校正OR=0.28,95%CI:0.09~0.91),无患肿瘤家族史人群下降到0.42倍(校正OR=0.42,95%CI:0.19~0.90)。随着吸烟量的增加,G/G或G/A基因型人群肺癌风险显著升高。rs5744962变异位点(T→C)可提高非吸烟人群的患肺癌风险至1.75倍(95%CI:1.02~3.00)。结论:选取的5个人类POLE1基因SNP的多态性可能与中国汉族人群肺癌遗传易感性有关,在携带rs5744738及与之紧密连锁的rs4883545、rs5744873突变纯合基因的人群,患肺癌的风险显著降低,而携带rs5744962、rs5745047突变基因位点的非吸烟人群患肺癌的风险升高。 展开更多
关键词 肺癌 关联研究 单核苷酸多态性 遗传易感性 pole1
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High efficiency continuous-wave tunable signal output of an intracavity singly resonant optical parametric oscillator based on periodically poled lithium niobate 被引量:5
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作者 丁欣 盛泉 +6 位作者 陈娜 禹宣伊 王睿 张衡 温午麒 王鹏 姚建铨 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4314-4318,共5页
In this paper we report on a continuous-wave (CW) intracavity singly resonant optical parametric oscillator (ICSRO) based on periodically poled LiNbO3 (PPLN) pumped by a diode-end-pumped CW Nd:YVO4 laser. Consi... In this paper we report on a continuous-wave (CW) intracavity singly resonant optical parametric oscillator (ICSRO) based on periodically poled LiNbO3 (PPLN) pumped by a diode-end-pumped CW Nd:YVO4 laser. Considering the thermal lens effects and diffraction loss, an optical ballast lens and a near-concentric cavity are adopted for better operation. Through varying the grating period and the temperature, the tunable signal output from 1406 nm to 1513 nm is obtained. At a PPLN grating period of 29 pm and a temperature of 413 K, a maximum signal output power of 820 mW at 1500 nm is achieved when the 808 nm pump power is 10.9 W, leading to an optical-to-optical conversion efficiency of 7.51%. 展开更多
关键词 CONTINUOUS-WAVE intracavity optical parametric oscillator periodically poled lithium niobate crystal tunable eye-safe laser
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