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Theoretical and Experimental Study of a Numerical Aperture for Multimode PCS Fiber Optics Using an Imaging Technique

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Chinese Physics Letters 2012年第11期29卷 119-122页

作者： saman q.mawlud Nahlah q.Muhamad Department of Physics Education CollageScientific DepartmentSalahaddin UniversityErbilKurdistan RegionIraq

We study theoretically and experimentally the properties of numerical aperture(NA)of multimode graded-index plastic core silica(PCS)fibers by using an image technique.A He-Ne laser at wavelength 632.8 nm and output power 1 mW is used as the transmitter light *** output beam images and intensity profiles of an optical fiber are investigated by using an imaging *** laser beam profiles captured by a sensitive digital Nikon camera are processed and analyzed by using a Gaussian intensity distribution in a 2D graph.A MathCAD 14 program is used for converting the image of the laser output beam into *** theoretical and experimental values of the numerical aperture for the used optical fiber in this study are found to be 0.5 and 0.4924,*** theoretical value of V-number is also calculated to be approximately 2482.

关键词： technique fiber PCS

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Prevalence of retinopathy of prematurity in Iran： asystematic review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2017年第8期10卷 1273-1279页

作者： saman Maroufizadeh Amir A lmasi-Hashiani Reza Omani samani Mahdi Sepidarkish Department of Epidemiology and Reproductive Health Reproductive Epidemiology Research Center Royan Institute for Reproductive Biomedicine ACECR Tehran 16635-148Iran

AIM： To estimate overall prevalence of retinopathy of prematurity （ROP） in Iran using a systematic review and Meta-analysis. METHODS： A systematic review and Meta-analysis was performed of all published studies pertaining to prevalence of ROP using international and national electronic databases （ISI Web of Sciences, PubMed, Scopus, Google Scholar, SlD, Maglran, and IranMedex） from their inception until May 2016 with standard keywords. Begg and Egger tests were used to examine the publication bias and Cochran test and f statistics were used to evaluate the statistical heterogeneity. Pooled estimate of the prevalence of ROP were calculated using random effects Meta- analysis. RESULTS： The publication bias assumption was rejected by Egger tests with P-value equal to 0.024. The results of Cochran test and 12 statistics revealed substantial heterogeneity （q=1099.02, df=25, f=97.7%, P=-0.001）. The overall prevalence of ROP using the random effect model in Iran was 26.1% （95% Ch 20.3%-31.8%）. CONCLUSION： The prevalence of ROP is relatively high in Iran. Low birth weight and gestational age are significant risk factors for the disease. Improved care, including oxygen delivery and monitoring, for preterm babies in all facility settings would reduce the number of babies affected with ROP.

关键词： retinopathy of prematurity preterm birth infant Meta-analysis systematic review Iran

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Prevalence of diabetic retinopathy in Iran： a systematic review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2017年第5期10卷 782-789页

作者： saman Maroufizadeh Amir Almasi-Hashiani Mostafa Hosseini Mahdi Sepidarkish Reza Omani samani Department of Epidemiology and Reproductive Health Reproductive Epidemiology Research Center Royan Institute for Reproductive Biomedicine ACECR Tehran 16635-148Iran Department of Epidemiology and Biostatistics School of Public Health Tehran University of Medical Sciences Tehran 14155-6446 Iran

AIM：To estimate the overall prevalence of diabetic retinopathy（DR） in Iran by a systematic review and ***：We conducted a search of all published literature on diabetic patients for the prevalence of DR using Web of Sciences, Pub Med, Scopus, Google Scholar, and national electronic databases SID, Magiran, and Iranmedex from their inception until September 2016 with standard keywords. Pooled estimates of the DR prevalence and the corresponding 95% confidence intervals（CI） were calculated using random effects ***：Thirty-one studies involving 23 729 patients with type Ⅰ and Ⅱ diabetes were included. The publication bias assumption for prevalence of DR was rejected by Begg and Egger tests（P=0.825, P=0.057, respectively）. The results of Cochran test and I^2 statistics showed considerable heterogeneity for prevalence of DR（q=1278.21, d.f.=30, P〈0.001 and I^2=97.7%）. The prevalence of DR, non-proliferative diabetic retinopathy（NPDR） and proliferative diabetic retinopathy（PDR） in Iranian diabetic patients were 41.9%（95% CI：35.6-48.2）, 32.2%（95% CI：28.7-35.8）, and 13.2%（95% CI：8.3-18.1）, respectively. CONCLUSION：The prevalence of DR in Iran appears a little high. NPDR was more common. This study highlights the necessity for DR screening and management in diabetic patients in Iran.

关键词： diabetic retinopathy Iran prevalence Meta-analysis systematic review

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非饱和粉砂临界状态的试验研究

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岩土工程学报 2018年第S1期40卷 8-15页

作者：蔡国庆 ASREAZAD saman 刘超赵成刚北京交通大学城市地下工程教育部重点实验室北京交通大学土木建筑工程学院天津市市政工程设计研究院桂林理工大学土木与建筑工程学院

非饱和土临界状态给出了土变形过程的终点,对于分析土的基本力学性质和建立相应的本构模型十分重要。以非饱和粉砂为研究对象,利用非饱和土双压力室三轴试验系统(GDS)开展相关试验研究,对不同干密度粉砂在不同净应力和吸力条件下剪切至... 详细信息

非饱和土临界状态给出了土变形过程的终点,对于分析土的基本力学性质和建立相应的本构模型十分重要。以非饱和粉砂为研究对象,利用非饱和土双压力室三轴试验系统(GDS)开展相关试验研究,对不同干密度粉砂在不同净应力和吸力条件下剪切至临界状态过程中,分别测定了强度、体变、含水率及饱和度等相关状态参量的变化规律。结果表明:剪切至临界状态过程中,不同干密度非饱和粉砂的强度和变形特性差异明显;随轴向应变的不断增加,不同初始干密度粉砂试样的偏应力、体应变以及饱和度曲线最终趋于稳定值,试样剪切达到临界状态。基于试验结果,揭示了临界状态条件下非饱和粉砂强度、孔隙比、孔隙水比体积随吸力的变化规律,并建立了q–p?、ν–ln p?、νw–ln p?平面内的临界状态线方程,提出了从强度、变形和孔隙水三个方面对非饱和粉砂临界状态进行综合描述的方法。

关键词：非饱和土粉砂三轴剪切试验临界状态

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圆锥角膜基质环植入手术前后人工晶状体度数的比较（英文）

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国际眼科杂志 2017年第7期17卷 1197-1201页

作者： Khosrow Jadidi saman Mohazzab-Torabi Farhad Nejat Shiva Pirhadi Hossein Aghamollaei Baqiyatallah医科大学眼科伊朗德黑兰19395-5487 Noor眼科学研究中心伊朗德黑兰196865-3111 视力健康研究中心伊朗德黑兰147367-4911 伊斯兰自由大学科学研究分院生物医学工程系伊朗德黑兰193793-4843 伊斯兰自由大学青年学者精英俱乐部北德黑兰分部伊朗德黑兰193793-4843

目的:评估圆锥角膜基质环(keraring 355°)(ICRS)植入术前术后3mo人工晶状体(IOL)度数的计算和生物学特征。方法:队列研究。收集18例(19眼)圆锥角膜接受角膜基质环植入术患者术前及术后3mo数据。分析裸眼视力(UCVA),最佳矫正视力(BCVA)... 详细信息

目的:评估圆锥角膜基质环(keraring 355°)(ICRS)植入术前术后3mo人工晶状体(IOL)度数的计算和生物学特征。方法:队列研究。收集18例(19眼)圆锥角膜接受角膜基质环植入术患者术前及术后3mo数据。分析裸眼视力(UCVA),最佳矫正视力(BCVA),屈光度,人工晶体度数计算公式,眼轴长度(AL)和角膜曲率。结果:患者平均年龄为29.58±0.6y。裸眼视力由0.84(0.35)LogMAR显著提高到0.43(0.31)LogMAR(Pq(P<0.001)and Holladay I(P<0.001)发生显著变化。结论:角膜基质环植入术后,视力,屈光率和角膜曲率均有所提高,此外,人工晶状体计算公式度数明显改变。然而,角膜基质环植入术过程没有过度干预眼轴长,但降低角膜曲率值使得人工晶状体度数计算更加精确,所有公式得出同一晶状体度数。

关键词：人工晶状体角膜基质环圆锥角膜

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Metabolome changes of tea leaf spot pathogen Phoma segeticola *** cultured on PDA with tea liquor

Metabolome changes of tea leaf spot pathogen Phoma segeticol...

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中国植物病理学会2019年学术年会

作者： Ren Yafeng Li Dongxue Wang Xue Yin qiaoxiu Dharmasena Dissanayake-saman-pradeep Jiang Shilong Wu Xian Song Baoan Chen Zhuo Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of EducationGuizhou University College of Agriculture Guizhou University

The fungal pathogen Phoma segeticola *** causes leaf spot on tea(Camellia sinensis) in Guizhou Province,*** study the mechanism of metabolomics during the stage of the pathogen infection,we design the experiment scheme of the pathogen culturing on PDA or PDA with tea liquor(Tea variety:Fudingdabaicha).The samples were detected using Nano-LC-MS-MS(TripleTOF 5600) under the mode of positive ion and negative ion,and then the data of the metabolites was further identified and quantified using the software XCMS and *** MS and MS-MS of the metabolites were annotated using the software metaX and in-house fragment spectrum *** were12 624 features in the positive mode,and 524 could be identified by ***,1 1008 features were detected in the negative mode,and 323 could be identified by *** addition,10850 high quality features were used to quantity following condition:ratio≥2 or ratio≤1/2;q value≤0.05;VIP≥1.122 2 and 1 048 were up-or down-regulated in the positive mode,*** the negative mode,9917 high quality features were used to quantity,and 1 192 and 1 078 features were up-or down-regulated,*** to the partial least-squares discrimination analysis,R value was 1.00,and q2 value was 0.98 in the positive *** R value was 1.00,and q2 value was 0.99 in the negative *** different metabolites were identified in 117 pathways,such as Biosynthesis of secondary metabolites(204),Biosynthesis of antibiotics(128),Microbial metabolism in diverse environments(95) and Arachidonic acid metabolism(45) et *** data would provide important reference for the pathogenesis of tea leaf spot.

关键词： Phoma segeticola var.camelliae Camellia sinensis metabolome

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