Purpoe: To evaluate retinal nerve fiber layer (RNFL) thickness measurements in local normal Chinese subjects of different age groups and analyse the correlation of RNFL thickness with age using scanning laser polarime...Purpoe: To evaluate retinal nerve fiber layer (RNFL) thickness measurements in local normal Chinese subjects of different age groups and analyse the correlation of RNFL thickness with age using scanning laser polarimetry (SLP,GDxVCC). To assess the reproducibility of RNFL thickness measurement with GDxVCC. Methods: The RNFL thickness of 67 normal subjects (123 eyes) were measured by GDxVCC. The average TSNIT parameters were calculated. The differences of RNFL thickness between sex,right and left eyes,superior and inferior were compared. The relationship between RNFL thickness and age was analyzed with correlation analysis and linear regression analysis. The intraclass correlation coefficients (ICC) of three images in every eye were calculated. Results: The average peripapillary RNFL thickness at the superior,inferior and whole ellipse regions in 123 eyes of 67 normal subjects were (70.30±6.76)(?)m,(67.35±6.77)(?)m and (56.87±4.53)(?) m,respectively. The average TNSIT standard deviation was 23.68±4.61 and the average inter-eye symmetric value was 0.86±0.11. There were significant difference of RNFL thickness between superior and inferior (t=4.952,P < 0.001). There were significant difference of inferior RNFL thickness and TNSIT standard deviation between right and left eyes (P=0.005 and 0.002),while not significant difference of superior RNFL thickness and whole mean RNFL thickness between right and left eye (P=0.086 and 0.529). There was no significant difference in TSNIT parameters between different genders. There was a slight negative correlation average RNFL thickness in superior sector with age (decreased approximately 0.15 microns per year,P=0.047) in the subjects aged below 60 years old. The ICC values of RNFL thickness were >0.8 in superior,inferior and global. Conclusions: The RNFL thickness can be measured accurately by GDxVCC and the reproducibility of RNFL thickness measurement by GDxVCC is good. There was a slight negative correlation between average RNFL thickness in superior with age. More researches on the effects of age on RNFL thickness by GDxVCC are needed.展开更多
The fractal curve is proposed as a novel scanning path used in Layered Manufacturing. Aiming at a limitation that the fractal curve can only fill a square region, a method is developed to realize the trimming of frac...The fractal curve is proposed as a novel scanning path used in Layered Manufacturing. Aiming at a limitation that the fractal curve can only fill a square region, a method is developed to realize the trimming of fractal curve in arbitrary boundary layer by means of judging intersection points between parameterized arbitrary boundary and a FASS (space filling, self avoiding, simple and self similar) fractal curve. Accordingly, the related algorithm concerning with determining intersection points has been investigated according to the recursion feature of the fractal curve, and in the process of the fractal curve traversed, the rule of judging intersection points is ascertained as well, so that the laser scanning beam can “walk” along the fractal curve inside the desired boundary, and arbitrary contour components are fabricated.展开更多
The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected sc...The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected scanning transmission electron microscopy(Cs-STEM)techniques.To facility our study,we grow two multiple quantum wells(MQWs)samples,which are almost identical except that in sample B a thin GaAs layer is inserted in each of the InGaAs well and AlGaAs barrier layer comparing to pristine InGaAs/AlGaAs MQWs(sample A).Our study indeed shows the direct evidences that In segregation occurs in the InGaAs/AlGaAs interface,and the effect of the Ga As insertion layer on suppressing the segregation of In atoms is also demonstrated on the atomic-scale.Therefore,the atomic-scale insights are provided to understand the segregation behavior of In atoms and to unravel the underlying mechanism of the effect of GaAs insertion layer on the improvement of crystallinity,interface roughness,and further an enhanced optical performance of InGaAs/AlGaAs QWs.展开更多
我国东南沿海尤其是温州地区广泛存在上覆深厚软土下覆不均匀卵石的地层。该区域的钻孔灌注桩常采用后注浆技术改善其承载性能。为了评价后注浆技术对这类地层中灌注桩承载力改善效果,开展了相应的模型试验,对比了不同注浆量对桩承载力...我国东南沿海尤其是温州地区广泛存在上覆深厚软土下覆不均匀卵石的地层。该区域的钻孔灌注桩常采用后注浆技术改善其承载性能。为了评价后注浆技术对这类地层中灌注桩承载力改善效果,开展了相应的模型试验,对比了不同注浆量对桩承载力的影响程度;并结合扫描电镜(scanning electron microscope,简称SEM)试验分析了浆液分布特点,探讨了浆液在卵石层中的扩散范围,研究了浆液扩散范围与桩承载力之间的关系。结果表明:浆液能够有效地填充桩端卵石层,注浆量的增加使得填充范围扩大,填充范围为3~4倍桩径时,桩的承载力改善最显著。在不均匀卵石持力层中存在一个最优注浆量,最优归一化注浆量约为2.8,若超过该最优注浆量归一化值,桩的承载力不再显著提高。单桩模型试验确定的最优注浆量与刘金砺公式[1]的预测结果接近。扫描电镜技术有助于评价桩的后注浆技术在上覆深厚软土下覆不均匀卵石的土层中的效果。展开更多
Summary： This study was aimed to evaluate the effectiveness of solution form of 17% ethylenediaminetetraacetic acid （EDTA） on removing smear layer of root canals at different exposure time periods and to provide sc...Summary： This study was aimed to evaluate the effectiveness of solution form of 17% ethylenediaminetetraacetic acid （EDTA） on removing smear layer of root canals at different exposure time periods and to provide scientific basis for EDTA as a choice of root canal irrigation in clinical practice. Twenty-five single-rooted teeth were randomly divided into 5 groups： control group （group A） was given 2.5% NaOC1, and 4 experimental groups were given 2.5% NaOC1 and 17% EDTA, including groups B, C, D and E with exposure time of 1, 3, 5 and 7 min, respectively. After preparation of the root canals, the teeth were split along their longitudinal axis, and the root sections were examined under scanning elec- tron microscope for evaluation of smear layer removal and erosion on the surface of the root canal walls. The specimens in group B showed presence of smear layer on the walls of the root canal with no statistical difference from that in group A （P〉0.05）. In groups C and D, partial removal of smear layer was obtained, and there was no significant difference between the two groups （P〉0.05）, but there was significant difference in removal of smear layer between group C and group B （P〈0.05）. Root canal walls in group E specimens showed almost complete removal of smear layer, and the removal of smear layer was significantly different from that in group D （P〈0.01）. There was no significant change in the structure of the surface of root canal for each sample. It was concluded that combined irrigation with 17% EDTA and 2.5% NaOC1 could remove the smear layer with no significant alteration in dentinal structure when the chelating agent was applied for 7 min. At 3 and 5 min of application, partial removal of smear layer was observed and at 1 min negligible removal of smear layer was achieved.展开更多
We propose a novel retinal layer segmentation method to accurately segment 10 retinal layers in optical coherence tomography(OCT)images with intraretinal fluid.The method used a fan filter to enhance the linear inform...We propose a novel retinal layer segmentation method to accurately segment 10 retinal layers in optical coherence tomography(OCT)images with intraretinal fluid.The method used a fan filter to enhance the linear information pertaining to retinal boundaries in an OCT image by reducing the effect of vessel shadows and fluid regions.A random forest classifier was employed to predict the location of the boundaries.Two novel methods of boundary redirection(SR)and similarity correction(SC)were combined to carry out boundary tracking and thereby accurately locate retinal layer boundaries.Experiments were performed on healthy controls and subjects with diabetic macular edema(DME).The proposed method required an average of 415 s for healthy controls and of 482 s for subjects with DME and achieved high accuracy for both groups of subjects.The proposed method requires a shorter running time than previous methods and also provides high accuracy.Thus,the proposed method may be a better choice for small training datasets.展开更多
The surface morphology of alloy layer of tinplate was studied by means of scanning electron microscopy. By using the layer on layer debonding technology of glow discharge spectrum, the contents of C and O at the bound...The surface morphology of alloy layer of tinplate was studied by means of scanning electron microscopy. By using the layer on layer debonding technology of glow discharge spectrum, the contents of C and O at the boundary of alloy layer and black plate were analyzed. And the corrosion characteristic of cavity of tinplate alloy layer was studied on-line and in-situ by means of electrochemical atomic force microscope. The corrosion depth of cavity of alloy layer in-situ after different corrosion time was measured. The results show that the cavity of alloy layer is a critical factor causing rapid decline of corrosion resistance of tinplate, and the formation of cavity of alloy layer is due to incorrect pretreatment of black plate before electrotinning. The cavity of alloy layer is the internal factor causing pitting corrosion of tinplate when the tinplate is applied to food packaging material. And the dynamic equation of pitting corrosion generated in the cavity of alloy layer conforms to logarithm law.展开更多
文摘Purpoe: To evaluate retinal nerve fiber layer (RNFL) thickness measurements in local normal Chinese subjects of different age groups and analyse the correlation of RNFL thickness with age using scanning laser polarimetry (SLP,GDxVCC). To assess the reproducibility of RNFL thickness measurement with GDxVCC. Methods: The RNFL thickness of 67 normal subjects (123 eyes) were measured by GDxVCC. The average TSNIT parameters were calculated. The differences of RNFL thickness between sex,right and left eyes,superior and inferior were compared. The relationship between RNFL thickness and age was analyzed with correlation analysis and linear regression analysis. The intraclass correlation coefficients (ICC) of three images in every eye were calculated. Results: The average peripapillary RNFL thickness at the superior,inferior and whole ellipse regions in 123 eyes of 67 normal subjects were (70.30±6.76)(?)m,(67.35±6.77)(?)m and (56.87±4.53)(?) m,respectively. The average TNSIT standard deviation was 23.68±4.61 and the average inter-eye symmetric value was 0.86±0.11. There were significant difference of RNFL thickness between superior and inferior (t=4.952,P < 0.001). There were significant difference of inferior RNFL thickness and TNSIT standard deviation between right and left eyes (P=0.005 and 0.002),while not significant difference of superior RNFL thickness and whole mean RNFL thickness between right and left eye (P=0.086 and 0.529). There was no significant difference in TSNIT parameters between different genders. There was a slight negative correlation average RNFL thickness in superior sector with age (decreased approximately 0.15 microns per year,P=0.047) in the subjects aged below 60 years old. The ICC values of RNFL thickness were >0.8 in superior,inferior and global. Conclusions: The RNFL thickness can be measured accurately by GDxVCC and the reproducibility of RNFL thickness measurement by GDxVCC is good. There was a slight negative correlation between average RNFL thickness in superior with age. More researches on the effects of age on RNFL thickness by GDxVCC are needed.
文摘The fractal curve is proposed as a novel scanning path used in Layered Manufacturing. Aiming at a limitation that the fractal curve can only fill a square region, a method is developed to realize the trimming of fractal curve in arbitrary boundary layer by means of judging intersection points between parameterized arbitrary boundary and a FASS (space filling, self avoiding, simple and self similar) fractal curve. Accordingly, the related algorithm concerning with determining intersection points has been investigated according to the recursion feature of the fractal curve, and in the process of the fractal curve traversed, the rule of judging intersection points is ascertained as well, so that the laser scanning beam can “walk” along the fractal curve inside the desired boundary, and arbitrary contour components are fabricated.
基金X.H.gratefully acknowledges the financial support from the National Natural Science Foundation of China(Grant No.21902096)the Scientific Research Foundation of Shaanxi University of Science and Technology(Grant No.126061803)+1 种基金S.M.and B.X.thank the National Natural Science Foundation of China(Grant No.21972103)the Shanxi Provincial Key Innovative Research Team in Science and Technology(Grant No.201703D111026).
文摘The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected scanning transmission electron microscopy(Cs-STEM)techniques.To facility our study,we grow two multiple quantum wells(MQWs)samples,which are almost identical except that in sample B a thin GaAs layer is inserted in each of the InGaAs well and AlGaAs barrier layer comparing to pristine InGaAs/AlGaAs MQWs(sample A).Our study indeed shows the direct evidences that In segregation occurs in the InGaAs/AlGaAs interface,and the effect of the Ga As insertion layer on suppressing the segregation of In atoms is also demonstrated on the atomic-scale.Therefore,the atomic-scale insights are provided to understand the segregation behavior of In atoms and to unravel the underlying mechanism of the effect of GaAs insertion layer on the improvement of crystallinity,interface roughness,and further an enhanced optical performance of InGaAs/AlGaAs QWs.
文摘我国东南沿海尤其是温州地区广泛存在上覆深厚软土下覆不均匀卵石的地层。该区域的钻孔灌注桩常采用后注浆技术改善其承载性能。为了评价后注浆技术对这类地层中灌注桩承载力改善效果,开展了相应的模型试验,对比了不同注浆量对桩承载力的影响程度;并结合扫描电镜(scanning electron microscope,简称SEM)试验分析了浆液分布特点,探讨了浆液在卵石层中的扩散范围,研究了浆液扩散范围与桩承载力之间的关系。结果表明:浆液能够有效地填充桩端卵石层,注浆量的增加使得填充范围扩大,填充范围为3~4倍桩径时,桩的承载力改善最显著。在不均匀卵石持力层中存在一个最优注浆量,最优归一化注浆量约为2.8,若超过该最优注浆量归一化值,桩的承载力不再显著提高。单桩模型试验确定的最优注浆量与刘金砺公式[1]的预测结果接近。扫描电镜技术有助于评价桩的后注浆技术在上覆深厚软土下覆不均匀卵石的土层中的效果。
基金supported by the Fundamental Research Funds for the Central Universities,China(No.2010JC030)
文摘Summary： This study was aimed to evaluate the effectiveness of solution form of 17% ethylenediaminetetraacetic acid （EDTA） on removing smear layer of root canals at different exposure time periods and to provide scientific basis for EDTA as a choice of root canal irrigation in clinical practice. Twenty-five single-rooted teeth were randomly divided into 5 groups： control group （group A） was given 2.5% NaOC1, and 4 experimental groups were given 2.5% NaOC1 and 17% EDTA, including groups B, C, D and E with exposure time of 1, 3, 5 and 7 min, respectively. After preparation of the root canals, the teeth were split along their longitudinal axis, and the root sections were examined under scanning elec- tron microscope for evaluation of smear layer removal and erosion on the surface of the root canal walls. The specimens in group B showed presence of smear layer on the walls of the root canal with no statistical difference from that in group A （P〉0.05）. In groups C and D, partial removal of smear layer was obtained, and there was no significant difference between the two groups （P〉0.05）, but there was significant difference in removal of smear layer between group C and group B （P〈0.05）. Root canal walls in group E specimens showed almost complete removal of smear layer, and the removal of smear layer was significantly different from that in group D （P〈0.01）. There was no significant change in the structure of the surface of root canal for each sample. It was concluded that combined irrigation with 17% EDTA and 2.5% NaOC1 could remove the smear layer with no significant alteration in dentinal structure when the chelating agent was applied for 7 min. At 3 and 5 min of application, partial removal of smear layer was observed and at 1 min negligible removal of smear layer was achieved.
基金supported by Grants from the Research and Development Projects in Key Areas of Guangdong Province(2020B1111040001)the National Natural Science Foundation of China(NSFC)(81601534,62075042,61805038)Guangdong-Hong Kong-Macao Intelligent Micro-Nano Optoelectronic Technology Joint Laboratory(2020B1212030010).
文摘We propose a novel retinal layer segmentation method to accurately segment 10 retinal layers in optical coherence tomography(OCT)images with intraretinal fluid.The method used a fan filter to enhance the linear information pertaining to retinal boundaries in an OCT image by reducing the effect of vessel shadows and fluid regions.A random forest classifier was employed to predict the location of the boundaries.Two novel methods of boundary redirection(SR)and similarity correction(SC)were combined to carry out boundary tracking and thereby accurately locate retinal layer boundaries.Experiments were performed on healthy controls and subjects with diabetic macular edema(DME).The proposed method required an average of 415 s for healthy controls and of 482 s for subjects with DME and achieved high accuracy for both groups of subjects.The proposed method requires a shorter running time than previous methods and also provides high accuracy.Thus,the proposed method may be a better choice for small training datasets.
文摘The surface morphology of alloy layer of tinplate was studied by means of scanning electron microscopy. By using the layer on layer debonding technology of glow discharge spectrum, the contents of C and O at the boundary of alloy layer and black plate were analyzed. And the corrosion characteristic of cavity of tinplate alloy layer was studied on-line and in-situ by means of electrochemical atomic force microscope. The corrosion depth of cavity of alloy layer in-situ after different corrosion time was measured. The results show that the cavity of alloy layer is a critical factor causing rapid decline of corrosion resistance of tinplate, and the formation of cavity of alloy layer is due to incorrect pretreatment of black plate before electrotinning. The cavity of alloy layer is the internal factor causing pitting corrosion of tinplate when the tinplate is applied to food packaging material. And the dynamic equation of pitting corrosion generated in the cavity of alloy layer conforms to logarithm law.
