A diode pumped Kerr-lens mode-locked femtosecond Yb：LSO laser is experimentally demonstrated for the first time. The 54fs laser pulses at central wavelength of 1052nm with a bandwidth of 22.5nm are obtained at the re...A diode pumped Kerr-lens mode-locked femtosecond Yb：LSO laser is experimentally demonstrated for the first time. The 54fs laser pulses at central wavelength of 1052nm with a bandwidth of 22.5nm are obtained at the repetition rate of 113 MHz. To the best of our knowledge, this is the shortest pulse duration ever produced from the Yb-doped orthosilicates lasers family.展开更多
AIM：To assess and compare the morphology of corneal flaps created by the Wavelight FS200 and Intralase FS60 femtosecond lasers in laser in situ keratomileusis（LASIK）.METHODS：Four hundred eyes of 200 patients were ...AIM：To assess and compare the morphology of corneal flaps created by the Wavelight FS200 and Intralase FS60 femtosecond lasers in laser in situ keratomileusis（LASIK）.METHODS：Four hundred eyes of 200 patients were enrolled in this study and divided into Wavelight FS200 groups（200 eyes） and Intralase FS60 groups（200 eyes）.Fourier-domain optical coherence tomography（RTVue OCT） was used to measure the corneal flap thickness of 36 specified measurements on each flap one week after surgery.Results were used to analyze the regularity,uniformity and accuracy of the two types of LASIK flaps.RESULTS：The mean thickness of corneal flap and central flap was 105.71±4.72 μm and 105.39±4.50 μm in Wavelight FS200 group and 109.78±11.42 μm and 109.15±11.59 μm in Intralase FS60 group,respectively.The flaps made with the Wavelight FS200 femtosecond laser were thinner than those created by the Intralase FS60 femtosecond laser（P=0.000）.Corneal flaps in the 2 groups were uniform and regular,showing an almost planar configuration.But the Wavelight FS200 group has more predictability and uniformity of flap creation.The mean deviation between achieved and attempted flap thickness was smaller in the Wavelight FS200 group than that in the Intralase FS60 group,which were 5.18±3.71 μm and 8.68±7.42 μm respectively.The deviation of more than 20 μm was 0.2% measurements in Wavelight FS200 group and 8.29% measurements in Intralase FS60 group.CONCLUSION：The morphologies of flaps created by Wavelight FS200 are more uniform and thinner than those created by Intralase FS60.展开更多
Rapid prototyping methods for the design and fabrication of polymeric labs-on-a-chip are on the rise,as they allow high degrees of precision and flexibility.For example,a microfluidic platform may require an optimizat...Rapid prototyping methods for the design and fabrication of polymeric labs-on-a-chip are on the rise,as they allow high degrees of precision and flexibility.For example,a microfluidic platform may require an optimization phase in which it could be necessary to continuously modify the architecture and geometry;however,this is only possible if easy,controllable fabrication methods and low-cost materials are available.In this paper,we describe the realization process of a microfluidic tool,from the computer-aided design(CAD)to the proof-of-concept application as a capture device for circulating tumor cells(CTCs).The entire platform was realized in polymethyl methacrylate(PMMA),combining femtosecond(fs)laser and micromilling fabrication technologies.The multilayer device was assembled through a facile and low-cost solvent-assisted method.A serpentine microchannel was then directly biofunctionalized by immobilizing capture probes able to distinguish cancer from non-cancer cells without labeling.The low material costs,customizable methods,and biological application of the realized platform make it a suitable model for industrial exploitation and applications at the point of care.展开更多
A new structure of the photonic crystal fiber（PCF）based Mach-Zednder interferometer（MZI）is fabricated and presented.The structure has microholes ablated by a femtosecond laser.The fringe visibility can be enhanced...A new structure of the photonic crystal fiber（PCF）based Mach-Zednder interferometer（MZI）is fabricated and presented.The structure has microholes ablated by a femtosecond laser.The fringe visibility can be enhanced more than 10 dB compared with the interferometer without a microhole.The interferometer is characterized by sodium chloride solutions for refractive index（RI）sensing.The RI sensitivities are greatly increased by the hole fabrication since it directly changes the cladding modes of the PCF.For the interferometer sensor with two holes,the RI sensitivity is 157.74 nm/RIU,which is 5 times than that of the sensor without a microhole.Microholes ablation with a femtosecond laser on PCF can increase the sensor＇s sensitivity dramatically.Femtosecond laser has a wide application prospect in the field of performance improvement of the sensors.展开更多
目的:探讨角膜地形图引导的飞秒激光制瓣的准分子激光原位角膜磨镶术(FS-LASIK)与有晶状体眼后房型环曲面人工晶状体(TICL)植入术矫正近视合并中高度散光的临床疗效。方法:选取2019-06/2021-06在河源爱尔眼科医院屈光中心就诊的近视合...目的:探讨角膜地形图引导的飞秒激光制瓣的准分子激光原位角膜磨镶术(FS-LASIK)与有晶状体眼后房型环曲面人工晶状体(TICL)植入术矫正近视合并中高度散光的临床疗效。方法:选取2019-06/2021-06在河源爱尔眼科医院屈光中心就诊的近视合并中高度散光患者60例115眼,按手术方式分组,接受角膜地形图引导的FS-LASIK患者32例62眼纳入A组;接受TICL植入术的患者28例53眼纳入B组。记录术前、术后3mo的裸眼视力(UCVA)、最佳矫正视力(BCVA)、球镜度、残余散光度,评估手术安全性和有效性,并利用Alpins矢量分析方法评估散光的矫正效果。结果:术后3mo,两组患者安全性指数(1.163±0.167 vs 1.136±0.194)和有效性指数(1.145±0.159 vs 1.123±0.196)均无差异(P>0.05),但散光矢量分析显示两组患者成功指数[0.125(0.091,0.200)vs 0.200(0.167,0.250)]、矫正指数[1.000(0.902,1.066)vs 0.834(0.783,0.869)]、变平指数[1.000(0.922,1.079)vs 0.835(0.795,0.870)]均有差异(P<0.01)。结论:角膜地形图引导的FS-LASIK与TICL植入术均能安全、有效地矫正近视散光,角膜地形图引导的FS-LASIK手术矫正散光的效果优于TICL植入术。展开更多
Direct analysis of copper-base alloys using laser ablation techniques is an increasingly common procedure in cultural heritage studies. However, main discussions remain focused on the possibility of using non-matrix m...Direct analysis of copper-base alloys using laser ablation techniques is an increasingly common procedure in cultural heritage studies. However, main discussions remain focused on the possibility of using non-matrix matched external reference materials. To evaluate the occurrence of matrix effects during in situ microanalysis of copper-base materials, using near infrared femtosecond laser ablation techniques (NIR fs-LA-ICP-MS), two bronzes, i.e., (Sn-Zn)-ternary and (Sn)-binary copper-matrix reference materials, as well as a reference synthetic glass (NIST-SRM-610) have been analyzed. The results have been compared to data obtained on a sulfide-matrix reference material. Similar values in relative sensitivity averages of 63Cu, 118Sn and 66Zn, as well as in 118Sn/63Cu and 66Zn/63Cu ratios were obtained, for all analyzed matrix types, i.e., copper-base-, silicate-, and sulfide-reference materials. Consequently, it is possible to determinate major and minor element concentrations in copper alloys, i.e., Cu, Sn and Zn, using silicate and sulfide reference materials as external calibrators, without any matrix effect and over a wide range of concentrations (from wt.% to ppm). Equally, Cu, Sn and Zn concentrations can be precisely determined in sulfides using homogeneous alloys (reference) materials as an external calibrator. Thus, it is possible to determine Cu, Sn and Zn in copper-base materials and their ore minerals, mostly sulfides, in a single analytical session, without requiring specific external calibrators for each matrix type. In contrast, immiscible elements in copper matrix, such as Pb and Fe show notable differences in their relative sensitivity values and ratios for different matrix-materials analyzed, implying that matrix-matched external calibrations remain to be applied for their trace quantification.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2013CB922402the National Key Scientific Instrument and Equipment Development Project under Grant No 2012YQ120047+1 种基金the Fundamental Research Funds for the Central Universities under Grant No JB140502the National Natural Science Foundation of China under Grant Nos 11174361 and61205130
文摘A diode pumped Kerr-lens mode-locked femtosecond Yb：LSO laser is experimentally demonstrated for the first time. The 54fs laser pulses at central wavelength of 1052nm with a bandwidth of 22.5nm are obtained at the repetition rate of 113 MHz. To the best of our knowledge, this is the shortest pulse duration ever produced from the Yb-doped orthosilicates lasers family.
文摘AIM：To assess and compare the morphology of corneal flaps created by the Wavelight FS200 and Intralase FS60 femtosecond lasers in laser in situ keratomileusis（LASIK）.METHODS：Four hundred eyes of 200 patients were enrolled in this study and divided into Wavelight FS200 groups（200 eyes） and Intralase FS60 groups（200 eyes）.Fourier-domain optical coherence tomography（RTVue OCT） was used to measure the corneal flap thickness of 36 specified measurements on each flap one week after surgery.Results were used to analyze the regularity,uniformity and accuracy of the two types of LASIK flaps.RESULTS：The mean thickness of corneal flap and central flap was 105.71±4.72 μm and 105.39±4.50 μm in Wavelight FS200 group and 109.78±11.42 μm and 109.15±11.59 μm in Intralase FS60 group,respectively.The flaps made with the Wavelight FS200 femtosecond laser were thinner than those created by the Intralase FS60 femtosecond laser（P=0.000）.Corneal flaps in the 2 groups were uniform and regular,showing an almost planar configuration.But the Wavelight FS200 group has more predictability and uniformity of flap creation.The mean deviation between achieved and attempted flap thickness was smaller in the Wavelight FS200 group than that in the Intralase FS60 group,which were 5.18±3.71 μm and 8.68±7.42 μm respectively.The deviation of more than 20 μm was 0.2% measurements in Wavelight FS200 group and 8.29% measurements in Intralase FS60 group.CONCLUSION：The morphologies of flaps created by Wavelight FS200 are more uniform and thinner than those created by Intralase FS60.
基金This work was supported by SMILE(a SAW-MIP Integrated device for oraL cancer Early detection)project,part of the ATTRACT program that has received funding from the European Union’s Horizon 2020 Research and Innovation Program(777222).
文摘Rapid prototyping methods for the design and fabrication of polymeric labs-on-a-chip are on the rise,as they allow high degrees of precision and flexibility.For example,a microfluidic platform may require an optimization phase in which it could be necessary to continuously modify the architecture and geometry;however,this is only possible if easy,controllable fabrication methods and low-cost materials are available.In this paper,we describe the realization process of a microfluidic tool,from the computer-aided design(CAD)to the proof-of-concept application as a capture device for circulating tumor cells(CTCs).The entire platform was realized in polymethyl methacrylate(PMMA),combining femtosecond(fs)laser and micromilling fabrication technologies.The multilayer device was assembled through a facile and low-cost solvent-assisted method.A serpentine microchannel was then directly biofunctionalized by immobilizing capture probes able to distinguish cancer from non-cancer cells without labeling.The low material costs,customizable methods,and biological application of the realized platform make it a suitable model for industrial exploitation and applications at the point of care.
文摘A new structure of the photonic crystal fiber（PCF）based Mach-Zednder interferometer（MZI）is fabricated and presented.The structure has microholes ablated by a femtosecond laser.The fringe visibility can be enhanced more than 10 dB compared with the interferometer without a microhole.The interferometer is characterized by sodium chloride solutions for refractive index（RI）sensing.The RI sensitivities are greatly increased by the hole fabrication since it directly changes the cladding modes of the PCF.For the interferometer sensor with two holes,the RI sensitivity is 157.74 nm/RIU,which is 5 times than that of the sensor without a microhole.Microholes ablation with a femtosecond laser on PCF can increase the sensor＇s sensitivity dramatically.Femtosecond laser has a wide application prospect in the field of performance improvement of the sensors.
文摘目的:探讨角膜地形图引导的飞秒激光制瓣的准分子激光原位角膜磨镶术(FS-LASIK)与有晶状体眼后房型环曲面人工晶状体(TICL)植入术矫正近视合并中高度散光的临床疗效。方法:选取2019-06/2021-06在河源爱尔眼科医院屈光中心就诊的近视合并中高度散光患者60例115眼,按手术方式分组,接受角膜地形图引导的FS-LASIK患者32例62眼纳入A组;接受TICL植入术的患者28例53眼纳入B组。记录术前、术后3mo的裸眼视力(UCVA)、最佳矫正视力(BCVA)、球镜度、残余散光度,评估手术安全性和有效性,并利用Alpins矢量分析方法评估散光的矫正效果。结果:术后3mo,两组患者安全性指数(1.163±0.167 vs 1.136±0.194)和有效性指数(1.145±0.159 vs 1.123±0.196)均无差异(P>0.05),但散光矢量分析显示两组患者成功指数[0.125(0.091,0.200)vs 0.200(0.167,0.250)]、矫正指数[1.000(0.902,1.066)vs 0.834(0.783,0.869)]、变平指数[1.000(0.922,1.079)vs 0.835(0.795,0.870)]均有差异(P<0.01)。结论:角膜地形图引导的FS-LASIK与TICL植入术均能安全、有效地矫正近视散光,角膜地形图引导的FS-LASIK手术矫正散光的效果优于TICL植入术。
文摘目的比较小切口飞秒激光角膜基质透镜取出术(Small incision lenticule extraction,SMILE)与飞秒激光辅助的 LASIK(Femtosecond laser-assisted laser in situ keratomileusis,FS-LASIK)矫正近视及近视散光术后24 h内疗效。方法行SMILE的近视患者18例(36眼),同期行FS-LASIK者15例(30眼),记录术前以及术后2、4、6、24 h的裸眼视力(Uncorrected visual acuity,UCVA)、等效球镜(Spherical equivalent,SE)、角膜光密度(Corneal densitometry,CD)、中央角膜厚度(Central corneal thickness,CCT)等。结果 SMILE组术后2 h 36眼中有17%≤0.1 logMAR UCVA,术后4、6、24 h 分别有22%、47%、92%≤0.1 logMAR UCVA;FS-LASIK组术后2 h 30眼中有10%≤0.1 logMAR UCVA,术后4、6、24 h 分别有30%、57%、90%≤0.1 logMAR UCVA。两组差异无统计学意义( P >0.05);两组术后24 h内屈光残留均在(±1.00D),两组比较术后各时间点SE无统计学差异( P >0.05)。两组术后平均角膜光密度均较术前显著增加( P <0.05),均在术后2h平均角膜光密度最大,术后4、6、24 h逐渐减小,两组比较无统计学意义( P >0.05);两组术后中央角膜厚度均随时间推移逐渐变薄,组内各时间点比较差异有统计学意义( P <0.05),组间比较无统计学差异( P >0.05)。结论 SMILE与FS-LASIK治疗近视和散光在术后最初24 h内视力和角膜状态均能快速恢复。该结果对于SMILE和FS-LASIK术后早期疗效的评估,尤其是对于具有迫切体检需求的患者,具有一定的参考意义。
文摘Direct analysis of copper-base alloys using laser ablation techniques is an increasingly common procedure in cultural heritage studies. However, main discussions remain focused on the possibility of using non-matrix matched external reference materials. To evaluate the occurrence of matrix effects during in situ microanalysis of copper-base materials, using near infrared femtosecond laser ablation techniques (NIR fs-LA-ICP-MS), two bronzes, i.e., (Sn-Zn)-ternary and (Sn)-binary copper-matrix reference materials, as well as a reference synthetic glass (NIST-SRM-610) have been analyzed. The results have been compared to data obtained on a sulfide-matrix reference material. Similar values in relative sensitivity averages of 63Cu, 118Sn and 66Zn, as well as in 118Sn/63Cu and 66Zn/63Cu ratios were obtained, for all analyzed matrix types, i.e., copper-base-, silicate-, and sulfide-reference materials. Consequently, it is possible to determinate major and minor element concentrations in copper alloys, i.e., Cu, Sn and Zn, using silicate and sulfide reference materials as external calibrators, without any matrix effect and over a wide range of concentrations (from wt.% to ppm). Equally, Cu, Sn and Zn concentrations can be precisely determined in sulfides using homogeneous alloys (reference) materials as an external calibrator. Thus, it is possible to determine Cu, Sn and Zn in copper-base materials and their ore minerals, mostly sulfides, in a single analytical session, without requiring specific external calibrators for each matrix type. In contrast, immiscible elements in copper matrix, such as Pb and Fe show notable differences in their relative sensitivity values and ratios for different matrix-materials analyzed, implying that matrix-matched external calibrations remain to be applied for their trace quantification.
