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Comparison of 80 W versus 120 W 532 nm Laser Prostatectomy for BPH  [PDF]
Richard K. Lee, Bilal Chughtai, Dean S. Elterman, Lauren Kurlander, Marika Yip-Bannicq, Laura McCormick, Steven A. Kaplan, Alexis E. Te
Open Journal of Urology (OJU) , 2013, DOI: 10.4236/oju.2013.31001
Abstract:

Purpose: Improvements to photoselective vaporization of the prostate (PVP) have been made over time, particularly with the introduction of higher power systems. Few studies however have compared the performance of these systems to their predecessors. The purpose of this study was to compare the clinical and perioperative outcomes of 80 W vs. 120 W PVP. Materials and Methods: A series of 267 and 209 consecutive patients underwent 80 W and 120 W PVP, respectively, from September 2001 to May 2009 at Weill Cornell Medical College (GreenLightTM laser system, American Medical Systems, Inc., Minnetonka, MN). Data were collected on patient demographics, International Prostate Symptom Score (IPSS), prostate-specific antigen (PSA), and perioperative parameters. Maximum flow rate (Qmax), postvoid residual (PVR), and transrectal ultrasound prostate volume were recorded. Statistical analyses were carried out utilizing the Shapiro-Wilk, Mann-Whitney, Wilcoxon and unpaired t tests (SPSS 15.0, SPSS Inc., Chicago, IL, USA). Results: Baseline parameters were similar between the two groups except for greater median age (72.8 vs. 69.2 years, p = 0.01) and lower median PSA (2.0 vs. 3.3, p

Diode Laser (532 nm) Induced Grafting of Polyacrylamide onto Gum Arabic  [PDF]
Nafie A. Almuslet,Elfatih Ahmed Hassan,Al Sayed Abd-El-Magied Al-Sherbini,Mohamed Gusm Alla Muhgoub
Journal of Physical Science , 2012,
Abstract: Initiation of graft copolymerisation of acrylamide (AAm) on Gum Arabic (GA, Acacia senegal) using diode laser (532 nm) was investigated. The results showed that the optimum conditions to achieve efficient graft copolymerisation were: 60 min laser irradiation time and 0.5 gm of GA, 0.142 gm of acrylamide (monomer). The percentage of graft efficiency and percentage of graft yield were 27.40% and 97.40%, respectively. The graft copolymers were characterised using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM) which proved a successful production of GA-g-Acrylamide (GA-g-AAm). The results proved that copolymerisation by laser can be considered as a new, effective and clean method for producing GA-g-AAm.
532nm脉冲激光辐照ccd实验研究  [PDF]
沈洪斌,沈学举,周冰,毛少娟,姜楠,李刚
强激光与粒子束 , 2009,
Abstract: ?采用532nm,10ns的脉冲激光对面阵ccd进行辐照实验,对每一阶段的实验现象和电路层面的破坏机理进行了深入分析,根据实验现象,把脉冲激光对ccd的硬破坏分为3个阶段:第1阶段在低能量密度激光辐照下,被破坏的ccd局部出现无法恢复的白色盲点,但其它部分仍可正常成像;第2阶段ccd探测器受到激光辐照后,在光斑处的时钟线方向出现白色竖直亮线,亮线处无法正常成像且激光辐照撤去后无法恢复;第3阶段受高能量密度激光辐照后,ccd完全失效,无法恢复成像。针对ccd的饱和及恢复阶段,利用matlab编码对分辨力靶板的成像数据进行处理,分析了激光辐照ccd对饱和像元数和对比度的影响。结果表明:当ccd受到激光辐照时,饱和像元数迅速增多,图像对比度迅速下降为零,激光脉冲消失后,整个ccd成像亮度下降,饱和像元数迅速下降为零,经过一段时间后ccd又恢复至线性工作状态,激光的能量密度越高,ccd恢复所需的时间就越长。研究还发现:当恢复时间超过0.6s,ccd出现不可恢复的白色条带,严重影响成像质量。
Measurements of Pulsed 532 nm Laser Breakdown Spectroscopy of Synthesized Magnetite Nanoferrofluid  [PDF]
Mohammad E. Khosroshahi, Maryam Tajabadi
World Journal of Nano Science and Engineering (WJNSE) , 2018, DOI: 10.4236/wjnse.2018.83003
Abstract: We describe the results of 532 nm pulse laser-induced breakdown spectroscopy (LIBS) of two samples of magnetite nanoparticles (SPIONs) nanoferrofluid synthesized at room (S1) and elevated temperatures (S2) and at three different laser energy levels and pulse frequency. The size of magnetite nanoparticles, size distribution, magnetic crystalline phase and magnetization were analyzed and measured using transmission electron microscopy (TEM), X-ray diffraction spectroscopy (XRD) and vibrating sample magnetometry (VSM). The SPIONs showed a distribution between 4 - 22 nm with a peak about 12 nm and saturation magnetization of about 65 emu/g. The Saha-Boltzmann analysis of spectra for medium energy level (1050 mJ) yields plasma temperatures of (3881 ± 200) K and (26,047 ± 200) K for Fe I and OV as the lowest and highest temperatures respectively. A range of corresponding electron density (Ne-) of (0.47 - 6.80) × 1020, (0.58 - 8.30) × 1020 and (0.69 - 9.96) × 1020 cm-3
Diagnostic Study of Nickel Plasma Produced by Fundamental (1064 nm) and Second Harmonics (532 nm) of an Nd: YAG Laser  [PDF]
M. Hanif, M. Salik, M. A. Baig
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.330203
Abstract: In the present work, we have studied the spatial evolution of the nickel alloy plasma produced by the fundamental (1064 nm) and second (532 nm) harmonics of a Q-switched Nd: YAG laser by placing the target material in air at atmospheric pressure. The four Ni I lines at 335.10 nm, 394.61 nm, 481.19 nm and 515.57 nm are used for the determination of electron temperature (Te) using Boltzmann plot method. The electron temperature is calculated as a function of distance from the target surface for both modes of Nd: YAG laser. In case of fundamental (1064 nm) mode of laser, the temperature varies from 13700 - 10270 K as the distance is varied from 0 to 2 mm. Whereas, in the case of second (532 nm) mode of laser it varies from 13270 - 9660 K for the same distance variation. The electron temperature has also been determined by varying the energy of the laser from 90 to 116 mJ, for the fundamental (1064 nm) harmonic and from 58 to 79 mJ for the second (532 nm) harmonics of the laser. The temperature increases from 14192 to 15765 K in the first case and from 13170 to 14800 K for the second case. We have also studied the spatial behavior of the electron number density in the plasma plume. The electron number density (Ne) in the case of fundamental (1064 nm) harmonic of the laser having pulse energy 125 mJ varies from 2.81 × 1016 to 9.81 × 1015 cm-3 at distances of 0 mm to 2.0 mm, whereas, in the case of second (532 nm) harmonic, with pulse energy 75 mJ it varies from 3.67 × 1016 to 1.48 × 1016 cm-3 for the same distance variation by taking Ni I line at 227.20 nm in both the cases.
车载式1064nm和532nm双波长米散射激光雷达  [PDF]
毛敏娟,吴永华,戚福弟,范爱嫒,岳古明,周军
强激光与粒子束 , 2005,
Abstract: ?新近研制的车载式双波长米散射激光雷达可用于1064nm和532nm两个波长对白天与夜晚对流层气溶胶消光系数垂直分布进行的探测。该激光雷达由激光发射单元、接收光学和后继光学单元、信号探测和采集单元以及系统运行控制单元组成,后继光路之间采用光纤导光、高低层分层探测等关键技术。该激光雷达使用1064nm和532nm的两个波长,其单发脉冲能量分别为400和300mj,重复频率都为20hz,光束发散角小于0.5mrad;望远镜接收视场为1~3mrad,滤光片的中心波长为1064nm和532nm,带宽1nm。分别使用r3236及h7680的pmt和vt120及phillips777的放大器对两个波长的信号进行探测;对532nm波长用3a/d采集卡、1064nm波长用了光子计数卡。给出了双波长测量对流层气溶胶消光系数垂直分布的结果,该激光雷达可以探测10-5~1之间的消光系数,探测高度可达10km以上。
Weak-signal conversion from 1550nm to 532nm with 84% efficiency  [PDF]
Aiko Samblowski,Christina E. Vollmer,Christoph Baune,Jaromir Fiurasek,Roman Schnabel
Physics , 2013, DOI: 10.1364/OL.39.002979
Abstract: We report on the experimental frequency conversion of a dim, coherent continuous-wave light field from 1550nm to 532nm with an external photon-number conversion efficiency of (84.4 +/- 1.5)%. We used sum-frequency generation, which was realized in a standing-wave cavity built around a periodically poled type I potassium titanyl phosphate (PPKTP) crystal, pumped by an intense field at 810 nm. Our result is in full agreement with a numerical model. For optimized cavity coupler reflectivities it predicts a conversion efficiency of up to 93% using the same PPKTP crystal.
The Effect of Q-Switched Nd:YAG 1064?nm/532?nm Laser in the Treatment of Onychomycosis In Vivo  [PDF]
Kostas Kalokasidis,Meltem Onder,Myrto-Georgia Trakatelli,Bertrand Richert,Klaus Fritz
Dermatology Research and Practice , 2013, DOI: 10.1155/2013/379725
Abstract: In this prospective clinical study, the Q-Switched Nd:YAG 1064?nm/532?nm laser (Light Age, Inc., Somerset, NJ, USA) was used on 131 onychomycosis subjects (94 females, 37 males; ages 18 to 68 years). Mycotic cultures were taken and fungus types were detected. The laser protocol included two sessions with a one-month interval. Treatment duration was approximately 15 minutes per session and patients were observed over a 3-month time period. Laser fluencies of 14?J/cm2 were applied at 9 billionths of a second pulse duration and at 5?Hz frequency. Follow-up was performed at 3 months with mycological cultures. Before and after digital photographs were taken. Adverse effects were recorded and all participants completed “self-evaluation questionnaires” rating their level of satisfaction. All subjects were well satisfied with the treatments, there were no noticeable side effects, and no significant differences were found treating men versus women. At the 3-month follow-up 95.42% of the patients were laboratory mycologically cured of fungal infection. This clinical study demonstrates that fungal nail infections can be effectively and safely treated with Q-Switched Nd:YAG 1064?nm/532?nm laser. It can also be combined with systemic oral antifungals providing more limited treatment time. 1. Introduction Onychomycosis is defined as a fungal infection of the nail that expands slowly and if left untreated leads to complete destruction of the nail plate. Onychomycosis can be dermatophytic (99%) and/or nondermatophytic (1%) (including yeasts) infections of the nail plate. The dermatophytes Trichophyton rubrum and Trichophyton mentagrophytes are the most common causative pathogens responsible for up to 90% of all cases [1]. Onychomycosis represents about 30% of all dermatophyte infections and accounts for 18%–40% of all nail disorders. The prevalence of onychomycosis ranges between 2% and 28% of the general population and it is estimated to be significantly higher in specific populations such as in diabetes mellitus, the immunosuppressed, and elderly [2, 3]. Among the nondermatophytes, the yeast Candida albicans, Candida tropicalis, aspergillus, and other molds may be responsible. It usually represents contamination and is an emerging problem in HIV patients. Toenails are far more likely to be involved than fingernails. Initially solitary nails are involved; later, many may be infected, but often one or more can stay disease-free. Onychomycosis has no tendency for spontaneous remission and should be considered as a problem with serious medical, social, and emotional
DESIGN OF A 532nm Nd:YVO4/KTP SINGLE-FREQUENCY LASER

Xu Chun-lin,Shen Nai-cheng,Zang Er-jun,Sun Yi-min,Lu Hai-ning,Zhao Kun,Zhang Xue-bin,

中国物理 B , 2001,
Abstract: A model of the laser-diode pumped solid-state laser is developed to deduce the minimum average radii of the pump beam in the solid medium, since the smaller the cavity waist, the higher the laser output power is expected to be. With an appropriate coupling system consisting of the collimating lens, prism pair and focusing lens, a diode-pumped single-frequency Nd:YVO4/KTP intracavity frequency-doubling cw laser has been demonstrated through the precise temperature control of the Nd:YVO4 crystal, the KTP crystal and the diode laser. The 532nm single-frequency output power of 40.4mW (in fact 55mW if the reflection loss of the triangular prism is taken into account) is obtained for an incident power of 515mW. It is derived theoretically and is verified in experiment that the frequency drift of the free-running laser can be reduced by increasing the cavity length.
1064nm、532nm、355nm波长脉冲激光辐照多晶硅损伤特性研究  [PDF]
冯爱新,庄绪华,薛伟,韩振春,孙铁囤,陈风国,钟国旗,印成,何叶
红外与激光工程 , 2015,
Abstract: 为系统研究不同波长激光与多晶硅材料的相互作用,采用1064nm、532nm、355nm波长单脉冲激光对多晶硅进行辐照实验,研究多晶硅在这三种波长激光下的损伤形态。实验结果表明:在其他参数不变的情况下,损伤阈值随激光波长的减小而变小,且与波长呈线性关系;在低能量密度水平下,355nm激光与物质作用主要是以光化学模型为主的光化学-光热共同作用方式,其他波长为光热模型;在激光能量密度处于低水平时,辐照区域出现相互连接的规则六边形微结构,并且六边形中心呈现圆形凸起状态,其产生是由液体横向流动的波动本质造成的,并与多晶硅表面的粗糙度有关。
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