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Structural Characteristics of Thunderstorms Associated with Negative Triggered Lightning Flashes
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作者 Xiaojie LIU Dong ZHENG +4 位作者 Yijun ZHANG Yang ZHANG Yanfeng FAN Weitao LYU Hai YU 《Advances in Atmospheric Sciences》 2025年第10期2053-2066,共14页
This study utilizes data from a 3D lightning location system,polarimetric radar,and current measurements from channels of triggered lightning flashes(TLFs)to analyze the structural characteristics of the parent thunde... This study utilizes data from a 3D lightning location system,polarimetric radar,and current measurements from channels of triggered lightning flashes(TLFs)to analyze the structural characteristics of the parent thunderstorms associated with negative TLFs in South China.The triggered-flash region(TFR)displays distinct stratiform cloud characteristics,including lower radar reflectivity heights and a predominance of ice crystals and dry snow above the 0℃ layer.In contrast,the thunderstorm convection core region(CCR)tends to have more graupel particles in the mixed-phase layers and exhibits an ice-water content peak approximately 3.4 times that of the TFR.The charge regions involved in discharges in TFRs exhibit a dipolar charge structure,with the-5℃ layer roughly dividing the upper positive and lower negative charge regions.Conversely,the CCRs feature a typical tripolar charge structure.The dominant dipole charge structure in the TFR results in an increase in the negative charge field below the negative charge region with height,providing a necessary condition for successfully triggering negative TLFs.Furthermore,the horizontal extent of TLFs is positively correlated with their duration and charge transfer.Regions where TLF channels with larger charge transfers propagate tend to have greater maximum radar reflectivity but lower average radar reflectivity compared to regions with TLFs with smaller charge transfer. 展开更多
关键词 thunderstorms structure triggered lightning flash charge region lightning location
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一种动态精准的Flash型FPGA内核电源控制技术
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作者 马金龙 潘乐乐 +2 位作者 韦文勋 江少祥 于宗光 《半导体技术》 北大核心 2026年第3期263-269,共7页
为满足Flash型现场可编程门阵列(FPGA)在多工作模式下内核电源供电的安全性与可靠性需求,设计并实现了一种Flash型FPGA内核电源控制逻辑电路。该电路利用Flash器件的非易失特性集成状态记忆模块,精准识别FPGA的5种工作状态。通过动态控... 为满足Flash型现场可编程门阵列(FPGA)在多工作模式下内核电源供电的安全性与可靠性需求,设计并实现了一种Flash型FPGA内核电源控制逻辑电路。该电路利用Flash器件的非易失特性集成状态记忆模块,精准识别FPGA的5种工作状态。通过动态控制JD7节点电平,实现了内核电源的精准管理与电气隔离:在非用户模式下将JD7置为电源电压V_(CC),以消除信号冲突风险;在用户模式下切换为GND,建立完整的电源回路。电路在一款60万门规模的Flash型FPGA中集成验证,测试结果表明,在55~125℃范围内及±5%电源电压波动条件下,全片擦除后静态电流低至1 mA,用户模式下功能正确。本研究为高可靠Flash型FPGA提供了一种有效的内核电源管理解决方案,显著提升了芯片的鲁棒性。 展开更多
关键词 Flash型现场可编程门阵列(FPGA) 内核电源供电 电源控制电路 非易失存储 高可靠性
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基于FPGA的供弹机构运动参数采集系统设计
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作者 张宝振 戴劲松 +1 位作者 王茂森 李想 《火力与指挥控制》 北大核心 2026年第3期165-173,共9页
针对现有的测量供弹机构运动参数的弹载记录仪数据易丢失和传输速度慢的问题,设计一种基于FPGA的弹载数据采集装置,利用FLASH掉电不丢失的特性保证数据采集的稳定性,通过USB2.0接口将保存的数据高速传输至上位机。经验证,该系统在恶劣... 针对现有的测量供弹机构运动参数的弹载记录仪数据易丢失和传输速度慢的问题,设计一种基于FPGA的弹载数据采集装置,利用FLASH掉电不丢失的特性保证数据采集的稳定性,通过USB2.0接口将保存的数据高速传输至上位机。经验证,该系统在恶劣环境下工作稳定,同时解决了数据易丢失和传输速度慢的问题,多路采样率最高可达100 kHz,可持续采集116 min。 展开更多
关键词 弹载数据采集 FPGA USB2.0 FLASH 供弹机构
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基于锁相环的Flash FPGA时钟网络架构设计
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作者 王雪萍 蔡永涛 +1 位作者 张长胜 马金龙 《电子与封装》 2026年第1期57-61,共5页
设计一种基于锁相环(PLL)的Flash FPGA时钟网络架构,该架构的全局时钟增加至3个,核心输出时钟额外增加2个,在芯片四周设计了1个带PLL的时钟调节电路和5个不带PLL的时钟调节电路,用于实现分频、倍频、相移和延时功能。仿真结果表明该架... 设计一种基于锁相环(PLL)的Flash FPGA时钟网络架构,该架构的全局时钟增加至3个,核心输出时钟额外增加2个,在芯片四周设计了1个带PLL的时钟调节电路和5个不带PLL的时钟调节电路,用于实现分频、倍频、相移和延时功能。仿真结果表明该架构可以满足整个芯片的时序配置需求。流片测试结果表明该架构的最高工作频率可达350 MHz,较原设计的时钟调节电路(180 MHz)有显著提升,达到国外同规模类型产品的水平。 展开更多
关键词 Flash FPGA 锁相环 时钟网络
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光电系统中控制器软件一致性设计
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作者 蔡彦博 温思达 《激光与红外》 北大核心 2026年第1期104-109,共6页
光电系统中的伺服控制器软件一般都带有装订参数,同一种设备的不同台次中装订参数会存在区别,若将其作为固定数值写在软件中,需要根据台次对软件进行区分,大批量生产后不便于进行软件版本管理。针对系统中所用TMS320F28335型数字信号处... 光电系统中的伺服控制器软件一般都带有装订参数,同一种设备的不同台次中装订参数会存在区别,若将其作为固定数值写在软件中,需要根据台次对软件进行区分,大批量生产后不便于进行软件版本管理。针对系统中所用TMS320F28335型数字信号处理器未配备片上EEPROM,不便于进行数据存储的情况。本文提出了一种通过对片上Flash进行读写的操作形式,用来对程序中的装订参数进行存储。实现装订参数的实时更新。通过对比传统的扩展片外EEPROM存储器的方案。试验结果表明,使用片上Flash存储和读写装订参数不需外部扩展硬件电路,不需进行外部GPIO及通信端口的配置,相较于外部EEPROM读取方法更为简单,具有较强的通用性和可靠性。 展开更多
关键词 伺服控制器软件 片上Flash 外部EEPROM 装订参数存储
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Review of Flash Joule Heating for the Synthesis of Graphene and Other Functional Carbon Materials
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作者 Zhiwu Tan Faisal Mahmood +8 位作者 Mengzhen Tian Yimeng Li Qingfa Zhang Zhong Ma Mingfeng Wang Weiwei Liu Shihong Zhang Haiping Yang Bin Li 《Carbon Energy》 2026年第1期223-252,共30页
Flash Joule heating(FJH),as a high-efficiency and low-energy consumption technology for advanced materials synthesis,has shown significant potential in the synthesis of graphene and other functional carbon materials.B... Flash Joule heating(FJH),as a high-efficiency and low-energy consumption technology for advanced materials synthesis,has shown significant potential in the synthesis of graphene and other functional carbon materials.Based on the Joule effect,the solid carbon sources can be rapidly heated to ultra-high temperatures(>3000 K)through instantaneous high-energy current pulses during FJH,thus driving the rapid rearrangement and graphitization of carbon atoms.This technology demonstrates numerous advantages,such as solvent-and catalyst-free features,high energy conversion efficiency,and a short process cycle.In this review,we have systematically summarized the technology principle and equipment design for FJH,as well as its raw materials selection and pretreatment strategies.The research progress in the FJH synthesis of flash graphene,carbon nanotubes,graphene fibers,and anode hard carbon,as well as its by-products,is also presented.FJH can precisely optimize the microstructures of carbon materials(e.g.,interlayer spacing of turbostratic graphene,defect concentration,and heteroatom doping)by regulating its operation parameters like flash voltage and flash time,thereby enhancing their performances in various applications,such as composite reinforcement,metal-ion battery electrodes,supercapacitors,and electrocatalysts.However,this technology is still challenged by low process yield,macroscopic material uniformity,and green power supply system construction.More research efforts are also required to promote the transition of FJH from laboratory to industrial-scale applications,thus providing innovative solutions for advanced carbon materials manufacturing and waste management toward carbon neutrality. 展开更多
关键词 APPLICATIONS by products flash graphene flash Joule heating functional carbon materials upscaling
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Spatiotemporal characteristics and onset processes of flash droughts during the growing season in Inner Mongolia,China
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作者 LIU Hongyu XIE Yunhu HAI Quansheng 《Journal of Mountain Science》 2026年第1期139-155,共17页
Flash droughts(FDs)develop quickly and can rapidly deplete soil moisture,posing significant threats to agriculture and pastoral systems.To investigate the spatiotemporal characteristics and development mechanisms of F... Flash droughts(FDs)develop quickly and can rapidly deplete soil moisture,posing significant threats to agriculture and pastoral systems.To investigate the spatiotemporal characteristics and development mechanisms of FDs in Inner Mongolia,China,and to assess the roles of key meteorological drivers in driving soil moisture variability,FD events were identified using root-zone soil moisture data during the growing seasons from 1982 to 2022.The results indicate the presence of five FD hotspot regions,located in the southern Alxa Plateau,the Hetao Plain in Bayannur,the northwestern Xilingol Plain,the western Liaohe River Plain,and the northern Da Hinggan Ling.Over 41 years,FDs occurred on average 7.44 events across the study area,with a mean duration of 9.17 pentads(1 pentad equals 5 days).The duration exhibited a significant increasing trend of 0.39 pentads/10 years.FD onsets primarily lasted for 2-3 pentads.During the FD development phase,precipitation and evapotranspiration decreased while temperature,potential evapotranspiration,incoming solar radiation,and vapor pressure deficit increased.The dominant meteorological drivers of FD development exhibited notable spatial heterogeneity across hotspot regions,and vapor pressure deficit consistently was the most influential factor.These findings improve the understanding of climate drivers at different stages of FD development and provide scientific support for early warning and prevention of droughts in Inner Mongolia. 展开更多
关键词 Flash drought Meteorological drivers XGBoost Inner Mongolia
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NAND Flash器件焊点可靠性及工艺优化研究
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作者 戴博 郭孟飞 +3 位作者 毛飘 李瑞麟 寇鹏 李媛 《电子产品可靠性与环境试验》 2026年第1期55-60,共6页
NAND Flash器件焊点可靠性是电子装联行业持续关注的重要课题之一。以TSOP封装类型的NAND Flash器件为研究对象,针对其焊点可靠性问题,对器件本体的热膨胀系数(CTE)及表面镀层进行了SEM测试分析。结果表明,该类器件本体与印制板(FR-4)... NAND Flash器件焊点可靠性是电子装联行业持续关注的重要课题之一。以TSOP封装类型的NAND Flash器件为研究对象,针对其焊点可靠性问题,对器件本体的热膨胀系数(CTE)及表面镀层进行了SEM测试分析。结果表明,该类器件本体与印制板(FR-4)之间存在较大的热失配,且引脚材料表面存在较薄的氧化物薄膜。通过采取优化措施进行试验样件对比验证,并对焊点进行加固处理,可使NAND Flash器件焊点的可靠性寿命在传统焊接基础上延长2倍以上。该工艺改进对航空航天及电子产品装联领域提升NAND Flash器件焊点可靠性具有重要参考价值。 展开更多
关键词 NAND Flash 焊点可靠性 电子装联 工艺优化
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基于电磁导航无人驾驶车辆系统的设计
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作者 普邑 赵旭锋 《山西电子技术》 2026年第1期72-74,78,共4页
设计了一款基于STC32F12K54单片机,以Keil5为开发环境,基于电磁导航的无人驾驶车辆。通过高精度ADC模块实时采集赛道上的电磁信号数据,并运用先进的差比和差算法,精确计算并确定车辆在赛道上的位置与姿态信息。随后对有刷电机的PID闭环... 设计了一款基于STC32F12K54单片机,以Keil5为开发环境,基于电磁导航的无人驾驶车辆。通过高精度ADC模块实时采集赛道上的电磁信号数据,并运用先进的差比和差算法,精确计算并确定车辆在赛道上的位置与姿态信息。随后对有刷电机的PID闭环控制等相关技术,结合TOF激光测距模块和陀螺仪等外设完成对赛道元素的识别,通过FLASH闪存技术实现了参数的灵活配置与快速调整,确保车辆能够迅速适应并应对各种赛道条件,最终实现无人驾驶并高速循迹一周。 展开更多
关键词 STC32F12K54 Keil5 ADC 差比和差 PID TOF 陀螺仪 FLASH闪存
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In-situ phosphatization of waterborne acrylic latex coatings for long-term corrosion protection of metal without flash rust
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作者 YUAN Rui TANG Zhi-xing +3 位作者 XIAO Min-di CAI Min-zhao ZHAO Zi-long GU Lin 《Journal of Central South University》 2026年第1期144-159,共16页
Waterborne acrylic coatings are widely utilized due to their cost-effectiveness,high transparency,strong resistance to weather and chemicals,impressive mechanical properties,and excellent adhesion to various substrate... Waterborne acrylic coatings are widely utilized due to their cost-effectiveness,high transparency,strong resistance to weather and chemicals,impressive mechanical properties,and excellent adhesion to various substrates.In these coatings,a reactive emulsifier containing phosphate groups can be integrated into the molecular chain during polymerization,which enhances the coating's compactness and corrosion resistance.This work focuses on the synthesis of styrene-butyl acrylate(St-BA)latex and methyl methacrylate-butyl acrylate(MMA-BA)latex using the reactive phosphate emulsifier ANPEO_(10)-P_(1) through seed emulsion polymerization,achieving a conversion rate of approximately 99%and a solid content close to 50%.The resulting coatings from St-BA and MMA-BA latexes demonstrated long-term corrosion protection for carbon steel and aluminum alloy due to in-situ phosphatization,effectively preventing flash rust.Notably,the MMA-BA coating exhibited remarkable durability,enduring immersion for up to 1224 h(51 d)on Q 235 carbon steel before reaching the failure threshold(|Z|0.01 Hz£106Ω·cm^(2))on Q 235 carbon steel.On 5052 aluminum alloy,the St-BA coating maintained|Z|0.01 Hz>10^(8)Ω·cm^(2) for 480 h(20 d).Furthermore,the corrosion resistance of St-BA and MMA BA coatings on Q 235 steel sheet and 5052 aluminum alloy surpassed that of commercially available MMA-BA and St BA coatings after immersion in a 3.5 wt%NaCl aqueous solution.This work also delves into the anticorrosion mechanism of MMA-BA and St-BA coatings. 展开更多
关键词 waterborne acrylic coating in-situ phosphatization emulsifier ANPEO_(10)-P_(1) flash rust long-term corrosion protection
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FLASH模式结合能谱纯化技术在腹部急危重症患者自由呼吸下全腹部双源CT扫描中的应用价值
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作者 陈德成 彭正峰 +8 位作者 王瑜 董永德 磨顶醒 汪时雨 江世健 黄丽花 赵家辉 朱刚明 陶燕英 《医学影像学杂志》 2026年第3期149-153,共5页
目的探讨FLASH模式结合能谱纯化技术在腹部急危重症患者自由呼吸下全腹部CT双源扫描中的应用价值。方法选取腹部急危重症患者80例,随机分为观察组和对照组各40例。两组均行双源CT扫描,观察组采用FLASH模式结合能谱纯化技术在自由呼吸下... 目的探讨FLASH模式结合能谱纯化技术在腹部急危重症患者自由呼吸下全腹部CT双源扫描中的应用价值。方法选取腹部急危重症患者80例,随机分为观察组和对照组各40例。两组均行双源CT扫描,观察组采用FLASH模式结合能谱纯化技术在自由呼吸下扫描,对照组采用常规方法屏气扫描。记录两组扫描时间、扫描长度、扫描剂量[包括容积CT剂量指数(CTDLVOL)、剂量长度乘积(DLP)、辐射有效剂量(ED)]。测量门静脉、腹主动脉、肝实质、脾脏、肾脏、腰大肌部位的CT值及噪声标准差(SD),根据公式计算信噪比(SNR),对两组图像质量进行客观评价;采用Likert 5分法评价图像运动伪影和诊断可置信度,对两组图像质量进行主观评价。SNR≥5.0、诊断可置信度评分≥3分为满足诊断需求。结果观察组扫描时间、CTDLVOL、DLP、ED均较对照组减少(P均<0.01),两组扫描长度比较差异无统计学意义(P>0.05)。两组各部位的SD和SNR比较差异均无统计学意义(P均>0.05)。两组图像运动伪影评分比较差异有统计学意义(P<0.05),诊断可置信度评分比较差异无统计学意义(P>0.05)。两组图像质量均满足诊断需求。结论腹部急危重症患者采用FLASH模式结合能谱纯化技术在自由呼吸状态下进行全腹部CT双源扫描,能够获得满足诊断需求的图像,并显著降低辐射剂量。 展开更多
关键词 体层摄影术 X线计算机 FLASH模式 能谱纯化 腹部急危重症
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Long-Term Chinese Herbs Decoction Administration for Management of Hot Flashes Associated with Endocrine Therapy in Breast Cancer Patients 被引量:2
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作者 Dong Xue Hong Sun Ping-ping Li 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2011年第1期74-78,共5页
Objective:To evaluate the effect of Chinese herbs decoction Shu-Gan-Liang-Xue on endocrine therapy-associated hot flashes symptom in breast cancer patients.Methods:Sixty-six patients with breast cancer receiving adj... Objective:To evaluate the effect of Chinese herbs decoction Shu-Gan-Liang-Xue on endocrine therapy-associated hot flashes symptom in breast cancer patients.Methods:Sixty-six patients with breast cancer receiving adjuvant endocrine therapy were categorized to two groups,the control group received endocrine therapy alone,the other group is administered with Chinese herbs decoction Shu-Gan-Liang-Xue besides the endocrine therapy:Shu-Gan-Liang-Xue decoction was administered above 6 months per year for more than 2 years.Frequency of hot flashes per day was recorded,and the effect of Shu-Gan-Liang-Xue decoction on hot flashes symptom being assessed with Kupperman Scoring Index.Results:Sixty cases were analyzed,32 cases in endocrine therapy combining Chinese herbs decoction group,28 cases in mere endocrine therapy group.For hot flashes symptom,in Chinese herbs decoction administration group,7 cases(21.9%) reported symptom disappeared,22 cases(68.7%) reported symptom alleviated,3 cases(9.4%) reported symptom not changed;in endocrine therapy alone group,5 cases(17.9%) reported symptom disappeared,13 cases(46.4%) reported symptom alleviated,10 cases(10/28,35.7%) reported symptom not changed.The difference between two groups was statistically significant(P=0.013).For sleeping disorder,in Chinese herbs decoction administration group,27 cases(84.4%) reported symptom improved,5 cases(15.6%) reported no change;in endocrine therapy alone group,16 cases(57.1%) symptom improved,12 cases(42.9%) reported no change in sleeping disorder(P=0.019),the difference was also of significance statistically.Conclusion:Long-term Chinese herbs decoction administration remarkably improved hot flashes symptom and sleeping disorder associated with endocrine therapy,meanwhile without definite toxicity and influence on the risk of recurrence of tumor. 展开更多
关键词 Breast cancer Endocrine therapy TAMOXIFEN Hot flashes Chinese herbs decoction
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Effect of Traditional Chinese Medicine inImproving Hot Flashes Symptom ofBreast Cancer 被引量:2
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作者 李萍萍 《Chinese Journal of Integrated Traditional and Western Medicine》 2004年第3期166-167,共2页
Breast cancer (BC) is the most common malignant tumor in women. Around 50% of BC receptor-positive patients are hormone-dependent cases, and it is necessary for them to use endocrine after operation. Through inhibitio... Breast cancer (BC) is the most common malignant tumor in women. Around 50% of BC receptor-positive patients are hormone-dependent cases, and it is necessary for them to use endocrine after operation. Through inhibition of estrogen level 展开更多
关键词 BC Effect of Traditional Chinese Medicine inImproving Hot flashes Symptom ofBreast Cancer TAM QOL
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The Characteristics of Ground Flashes in Beijing and Lanzhou Regions 被引量:5
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作者 郄秀书 郭昌明 刘欣生 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第4期471-478,共8页
Over twenty thousand lightning location data obtained by using Lightning Location System(LLS) from Lanzhou and Beijing regions have been analysed to ascertain the characteristics of ground flashes in both regions. The... Over twenty thousand lightning location data obtained by using Lightning Location System(LLS) from Lanzhou and Beijing regions have been analysed to ascertain the characteristics of ground flashes in both regions. The strength of positive flashes is 5 times higher in Lanzhou than in Beijing. The strength of positive flashes is 3 times and 2.2 times as large as negative flashes in Beijing and in Lanzhou respectively. It has been found that the strength of positive and negative flashes is submitted to the normal distribution, and is independent of the characteristics of thunderstorm. So the lightning strength obtained by DF may be used to forecast the coming of thunderstorm. Although the stroke number in both regions decreases as exponent regulation, the maximum number of return stroke for one lightning in Beijing is more than that in Lanzhou. The peak flash rate occurs in late afternoon for both regions, but the maximum and minimum flash rate appeared an hour earlier in Beijing than in Lanzhou.The relationship between DF display and lightning radiation electric field, discharge current is obtained. 展开更多
关键词 The Characteristics of Ground flashes in Beijing and Lanzhou Regions
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Acupuncture for the Treatment of Hot Flashes in Men with Advanced Prostate Cancer 被引量:1
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作者 Jillian L. Capodice Philippa Cheetham +2 位作者 Mitchell C. Benson James M. McKiernan Aaron E. Katz 《International Journal of Clinical Medicine》 2011年第1期51-55,共5页
PURPOSE: To test the safety and efficacy of acupuncture in reducing hot flashes in men with advanced prostate cancer (CaP) undergoing androgen deprivation therapy. METHODS: A single-arm, pilot study was undertaken to ... PURPOSE: To test the safety and efficacy of acupuncture in reducing hot flashes in men with advanced prostate cancer (CaP) undergoing androgen deprivation therapy. METHODS: A single-arm, pilot study was undertaken to evaluate acupuncture treatment for hot flashes experienced by CaP patients undergoing hormonal therapy. Sixteen advanced CaP patients undergoing androgen deprivation therapy (ADT) received standardized full body and auricular acupunc-ture 1x/week for 14 weeks. Patients were evaluated at 0, 7, 14, and an additional 14-wk follow-up (F/U) (28-wks). Safety was measured by monitoring for adverse events over the treatment period. Serum testosterone was measured at 0 and 14-wks. Quality of life (QOL) was measured by the hormone domain of the Expanded Prostate Index Composite (EPIC), at the 0, 7, 14, and 28-wks and patient reported hot flash frequency was assessed weekly. Safety endpoints were serum testosterone and analysis of adverse events. Efficacy endpoints were scores on the EPIC and the number of pa-tient reported hot flashes. RESULTS: 17 patients were enrolled and 15 completed the trial. Of 15 evaluable patients the median age was 68 ± 8.19. Serum analysis demonstrated no change in testosterone at baseline 9.5 ng/ml ± 8.9 vs. end-point 14 ± 8.78 (p = 0.101). No adverse events were reported. Data analysis of the EPIC demonstrated a trend toward improvement after 7 wks and a significant improvement following 14 wks of acupuncture (p = 0.01). Analysis of patient reported frequency showed a significant reduction in the number of hot flashes at 7-wk (6, p = 0.04), 14-wk (2.6, p = 0.001), and 28-wk F/U (3.2, p = 0.01) as compared to baseline 9.57 ± 3.98. CONCLUSIONS: The administration of acupuncture in men with advanced CaP appears to significantly decrease the frequency of hot flashes. No serious ad-verse events were noted and serum testosterone levels were unchanged from baseline suggesting that the mechanism of action of acupuncture for hot flash amelioration is not via increase in testosterone. 展开更多
关键词 PROSTATE CANCER ACUPUNCTURE HOT flashes
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Characteristics of thunderstorms and lightning flashes in the Chinese inland plateau 被引量:1
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作者 TingLong Zhang Tong Zhang Yang Zhao XiangZhen Kong YanHui Wang 《Research in Cold and Arid Regions》 2010年第3期271-277,共7页
The electrical characteristics of thunderstorms in three different altitude regions of the Chinese inland plateau have been analyzed in this paper. The results show, according to the polarity of the surface electric ... The electrical characteristics of thunderstorms in three different altitude regions of the Chinese inland plateau have been analyzed in this paper. The results show, according to the polarity of the surface electric (E) field, that the thunderstorms can be divided into two categories in the study regions: one showing the normal tripole electrical charge structure (normal-type), and the other showing the special tripole charge structure with a larger-than-usual lower positive charge center (LPCC) at the base of thunderstorm (special-type), where the induced surface E field is controlled by the LPCC when a thunderstorm is overhead. We find that the two types of thunderstorms have different occurrences in different regions, and the percentage of special-type thunderstorms increases with the altitude. On the whole, the flash rate of thunderstorms is quite low, and the mean value is about 1-3 fl/min, while the flash rate of special-type is slightly greater than that of the normal-type thunderstorm. The statistical results of cloud-to-ground flash (CG) numbers indicate that the ratio of +CG flash increases with the altitude, with the value about 14.7 percent through 25.4 percent. 展开更多
关键词 thunderstorm flash rate cloud-to-ground flash
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Effect of acupuncture on menopausal hot flashes:Study protocol for a randomized controlled clinical trial
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作者 Kun XU Anna Bogachko(Sweden) +5 位作者 Shan-shan LI Xuan YIN Hong-yu YUE Tian LI Li-xing LAO Shi-fen XU 《World Journal of Acupuncture-Moxibustion》 CSCD 2021年第4期324-329,共6页
Background:Hot flashes are one of the most common symptoms in menopause and significantly affect the quality of life of 67% of menopausal women.Acupuncture is found to be a low risk treatment in treating hot flashes b... Background:Hot flashes are one of the most common symptoms in menopause and significantly affect the quality of life of 67% of menopausal women.Acupuncture is found to be a low risk treatment in treating hot flashes but the evidence for its effectiveness is inconclusive.We developed an optimized acupuncture treatment protocol and designed a randomized controlled trial(RCT) to assess the efficacy of acupuncture for reducing hot flashes in menopausal women.Methods:This is a single-site,single-blind,randomized sham-controlled trial with two parallel arms.A total of 60 eligible patients will be recruited and randomly assigned to either the acupuncture group(n=30) or the sham acupuncture group(n=30).Treatment will be given twice a week,for 30 min,for six consecutive weeks.The primary outcome is the hot flashes scores,assessed using the validated hot flashes diary at baseline,week 3,week 6 and week 10.The secondary outcome will be measured by menopause-specific quality of life(MENQOL) at baseline,week 6,and week 10.Meanwhile,any adverse events will be recorded.Discussion:If the outcome of this study confirms acupuncture to be an effective therapy to reduce hot flashes in menopausal women,we expect this study to inspire further investigations and provide useful information in forming an optimal acupuncture treatment protocol for clinic.Trial registration:Chinese Clinical Trial Registry identifier:ChiCTR1800018638,Date of registration:30 th September 2018.URL:http://www.chictr.org.cn/showproj.aspx?proj=31462. 展开更多
关键词 Hot flashes MENOPAUSE ACUPUNCTURE Randamized controlled trial(RCT)
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Comparative research between acupuncture and Climen in treatment of menopausal hot flashes:A randomized controlled trial
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作者 Hai-tao TU Xin ZHOU +2 位作者 Xun ZHUANG Jun HE Zhong-hao XIONG 《World Journal of Acupuncture-Moxibustion》 CSCD 2021年第4期285-290,共6页
Objective:To compare the therapeutic effect on menopausal hot flashes between acupuncture and Climen so as to provide a new approach to the treatment of this disease.Methods:A total of 80 cases in line with inclusion ... Objective:To compare the therapeutic effect on menopausal hot flashes between acupuncture and Climen so as to provide a new approach to the treatment of this disease.Methods:A total of 80 cases in line with inclusion criteria were randomized into a treatment group(treated with acupuncture) and a control group(oral administration with climen),40 cases in each one.The treatment for 1 month was as 1 course and lasted consecutively for 2 courses.Before and after treatment,the contents of serum estrogen(estradiol,E_(2)) and 5-hydroxytryptamine(HT) and the scores of the attack frequency and severity scale of hot flashes and sweating,domestic modified Kupperman scale and traditional Chinese medicine(TCM) symptom scale were observed,and the clinical therapeutic effect was evaluated in the two groups separately.Results:Before treatment,there was no difference in the content of E_(2) and 5-HT,the score of hot flashes and sweating,Kupperman score and TCM symptom score in the patients between two groups,indicating the comparability(all P>0.05).Compared with the data before treatment,the contents of serum E_(2)(treatment group vs control group:22.24±11.02 vs 33.12±1.01;22.11±10.19 vs 25.29±2.23) and5-HT(treatment group vs control group:96.12±8.21 vs 131.21±30.21;96.98±7.99 vs 108.29±22.08),the score of hot flashes and sweating(treatment group vs control group:8.24±1.02 vs 3.12±1.01;8.11±1.19 vs 5.29±2.23),Kupperman score(treatment group vs control group:26.12±2.21 vs11.21±0.21;26.98±1.99 vs 18.29±2.08) and TCM symptom score(treatment group vs control group:18.97±3.87 vs 10.12±0.16;19.01±2.29 vs 15.61±2.89) were statistically different after treatment in the two groups(all P<0.05).After treatment,the contents of serum E_(2) and 5-HT,the score of hot flashes and sweating,Kupperman score and TCM symptom score in the treatment group were all different statistically compared with the control group(all P<0.05).There was statistical difference in clinical therapeutic effect in the patients between two group,in which,the therapeutic effect in the treatment group was better than that in the control group(90% vs 77.5%,P<0.05).Conclusion:Acupuncture effectively reduces Kupperman score and TCM symptom score in the patients and its therapeutic effect is better than climen.Regarding relieving hot flashes symptoms in menopausal patients of kidney yin deficiency and improving in attack frequency and severity of hot flashes and sweating,the effects of acupuncture are superior to Climen.Acupuncture obviously increases the contents of serum E_(2) and 5-HT. 展开更多
关键词 Menopausal hot flashes Kidney yin deficiency ACUPUNCTURE CLIMEN Randomized controlled trial(RCT)
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Flashes formation and evaluation during linear friction welding of TC4 alloy
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作者 姬书得 刘建光 +3 位作者 高双胜 刘伟 岳玉梅 陶军 《China Welding》 EI CAS 2013年第2期18-23,共6页
By the 3D coupled thermo-mechanical finite element model of linear friction welding of TC4 titanium alloy, the relation between the temperature and the flashes is researched. The numerical simulation results show that... By the 3D coupled thermo-mechanical finite element model of linear friction welding of TC4 titanium alloy, the relation between the temperature and the flashes is researched. The numerical simulation results show that the flashes with the wrinkles appear only when the temperature of material in the friction surface is high enough. The flashes, which are made up of material with high temperature, are squeezed out of the component. The appearance of flashes makes the temperature of material in the friction susface slowly increase or even decrease. Compared with the oscillation frequency and the oscillation amplitude, the friction pressure' s increase can mare easily attain the flashes with the bigger dimensionz. 展开更多
关键词 linear friction welding TEMPERATURE flashes numerical simulation
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Effect of temperature field on flashes formation of continuous drive friction welding
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作者 姬书得 刘建光 +3 位作者 高双胜 岳玉梅 陶军 吕赞 《China Welding》 EI CAS 2013年第3期46-50,共5页
On basis of the finite element software DEFORM, the 2D coupled thermo-mechanical model of continuous drive friction welding of ring parts is established. The temperature and the flashes during the welding process are ... On basis of the finite element software DEFORM, the 2D coupled thermo-mechanical model of continuous drive friction welding of ring parts is established. The temperature and the flashes during the welding process are investigated. The results of numerical simulation show that the temperature of friction surface is higher than that of other region and the peak temperature increases with the increase of welding time. During the process of friction stage, no flash appears because of the low temperature and the small axial friction pressure. At the forging stage, the flashes appear, whose dimensions and bending degree increase with the increase of welding temperature. Moreover, with the increase of rotational velocity and axial forging pressure, the dimensions and the bending degree of flashes of continuous drive friction welding increase. 展开更多
关键词 continuous drive friction welding temperature flashes numerical simulation
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