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近视患儿配戴角膜塑形镜后的视网膜周边离焦

眼科新进展 2023年第12期43卷 983-986,991页

作者：帅钰于嘉张晶郭玉娟刘曦周跃华成都中医药大学眼科学院四川省成都市610075 成都中医大银海眼科医院四川省成都市610075 北京茗视光眼科北京市100062 宜宾市第二人民医院四川省宜宾市644002

目的应用多光谱屈光地形图(MRT)分析近视患儿配戴角膜塑形镜(Ok镜)后视网膜周边不同区域的离焦情况。方法回顾性研究。纳入2021年1月至4月在成都中医大银海眼科医院验配Ok镜的近视患儿128例128眼(右眼),于戴Ok镜前采用角膜地形图仪测量... 详细信息

目的应用多光谱屈光地形图(MRT)分析近视患儿配戴角膜塑形镜(Ok镜)后视网膜周边不同区域的离焦情况。方法回顾性研究。纳入2021年1月至4月在成都中医大银海眼科医院验配Ok镜的近视患儿128例128眼(右眼),于戴Ok镜前采用角膜地形图仪测量患儿角膜陡峭曲率、角膜平坦曲率、陡峭子午线方向的角膜偏心率和平坦子午线方向的角膜偏心率,光学生物测量仪测量患儿戴Ok镜前的中央角膜厚度、基线眼轴长度(AL1)及戴Ok镜1年后的眼轴长度(AL2),MRT获取患儿戴Ok镜1年后视网膜离焦量(RDV)。根据戴Ok镜1年后不同眼轴年增长量(CAL)将研究对象分为SAL组(CAL≤0.3 mm)和LAL组(CAL>0.3 mm),比较两组患儿戴Ok镜1年后视网膜周边0°~10°、>10°~20°、>20°~30°、>30°~40°、>40°~53°范围内的平均离焦量(分别记为:RDV 0°~10°、RDV10°~20°、RDV20°~30°、RDV30°~40°、RDV40°~53°)以及视网膜0°~53°范围内总体离焦量的平均值(TRDV),视网膜上方、下方、颞侧、鼻侧四个象限的平均离焦量(分别记为:RDV-S、RDV-I、RDV-T、RDV-N),分析视网膜周边不同区域离焦情况对眼轴增长的影响。结果戴Ok镜1年后,SAL组患儿视网膜周边RDV20°~30°、RDV30°~40°、RDV40°~53°、TRDV、RDV-I、RDV-T均低于LAL组(均为P0.05);视网膜周边RDV10°~20°、RDV20°~30°、RDV30°~40°、RDV40°~53°、TRDV、RDV-I、RDV-T与CAL均呈正相关(均为P<0.05)。结论近视患儿视网膜周边10°~53°范围的离焦状态与眼轴增长密切相关,RDV越低眼轴增长越缓慢。

关键词：多光谱屈光地形图视网膜周边离焦眼轴长度角膜塑形镜近视患儿

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Superconductivity above 70 k observed in lutetium polyhydrides

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Science China(Physics,Mechanics & Astronomy) 2023年第6期66卷 95-100页

作者： Zhiwen Li Xin He Changling Zhang ke Lu Baosen Min Jun Zhang Sijia Zhang Jianfa Zhao Luchuan Shi Yi Peng Shaomin Feng Zheng Deng Jing Song Qingqing Liu Xiancheng Wang Richeng yu Luhong Wang Yingzhe Li Jay D.Bass Vitali Prakapenka Stella Chariton Haozhe Liu Changqing Jin Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100190China Songshan Lake Materials Laboratory Dongguan523808China Shanghai Advanced Research in Physical Sciences Shanghai201203China Department of Geology University of Illinois at Urbana ChampaignUrbana61801USA Center for Advanced Radiations Sources University of ChicagoChicago60637USA Center for High Pressure Science&Technology Advanced Research Beijing100094China

The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be *** lutetium polyhydrides were successfully synthesized at high pressure and high temperature conditions using a diamond anvil cell in combinations with the in-situ high pressure laser heating *** resistance measurements as a function of temperature were performed at the same pressure of synthesis in order to study the transitions of superconductivity(SC).The superconducting transition with a maximum onset temperature(Tc)71 k was observed at pressure of 218 GPa in the *** Tcdecreased to 65 k when pressure was at 181 *** the evolution of SC at applied magnetic fields,the upper critical field at zero temperatureμ0Hc2(0)was obtained to be~36 *** in-situ high pressure X-ray diffraction experiments imply that the high TcSC should arise from the Lu4H23phase with Pm3n symmetry that forms a new type of hydrogen cage framework different from those reported for previous light rare earth polyhydride superconductors.

关键词： lutetium polyhydrides superconductors at high pressures high pressure synthesis

A new spectral index for the quantitative identification of yellow rust using fungal spore information

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Big Earth Data 2021年第2期5卷 201-216页

作者： yu Ren Huichun Ye Wenjiang Huang Huiqin Ma Anting Guo Chao Ruan Linyi Liu Binxiang Qian key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina Hainan key Laboratory of Earth Observation Hainan Institute of Aerospace InformationChinese Academy of SciencesSanyaChina

Yellow rust(Puccinia striiformis ***)is a frequently occurring fungal disease of winter wheat(Triticum aestivum L.).During yellow rust infestation,fungal spores appear on the surface of the leaves as yellow and narrow stripes parallel to the leaf *** analyzed the effect of the fungal spores on the spectra of the diseased leaves to find a band sensitive to yellow rust and established a new vegetation index called the yellow rust spore index(YRSI).The estimation accuracy and stability were evaluated using two years of leaf spectral data,and the results were compared with eight indices commonly used for yellow rust *** results showed that the use of the YRSI ranked first for estimating the disease ratio for the 2017 spectral data(R^(2)=0.710,RMSE=0.097)and outperformed the published indices(R^(2)=0.587,RMSE=0.120)for the validation using the 2002 spectral *** random forest(RF),k-nearest neighbor(kNN),and support vector machine(SVM)algorithms were used to test the discrimination ability of the YRSI and the eight commonly used indices using a mixed dataset of yellow-rust-infested,healthy,and aphid–infested wheat spectral *** YRSI provided the best performance.

关键词： Yellow rust spectral index fungal spores quantitative identification hyperspectral remote sensing winter wheat

Permanent Magnetic Properties of Melt-Spun YCo5Cx Ribbons

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Chinese Physics Letters 2010年第6期27卷 210-212页

作者： WANG Fei YAN yu yuAN Zhou BAI Xue DU Xiao-Bo WANG Wen-Quan SU Feng JIN Han-Min State key Laboratory for Superhard Materials and Department of Physics Jilin University Changchun 130012

Ribbons of nominal compositions YCo5 Cx （x = 0, 0.2, 0.4, 0.6） are prepared by melt spinning at surface velocities v = 5, 10, 15, 20, 25, 30 and 35 m/s. YCo5 ribbon is crystallized in a single YCo5 phase of hexagonal CaCu5 structure. A small quantity of YCoC2 phase appears in the ribbons with C addition besides the YCo5 phase. With the increase of x the lattice constant c increases and a along with the unit cell volume decreases. The largest values of iHc = 888 kA/m and （BH）max = 58.4 k Jim3 at present for the YCo5 ribbon system were obtained with x = 0.4 and v = 20 m/s. The improvement of the permanent magnetic properties is rooted in the refinement of the microstructure and the appearance of the YCoC2 phase which can act as domain wall pinning centers.

关键词： Lymphocytes Magnetic Properties Ribbons

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甲基胺溴化铅晶体粉末的温度依赖光致发光

强激光与粒子束 2023年第11期35卷 152-156页

作者：于海龙吴文智黑龙江大学电子工程学院哈尔滨150080

采用稳态光致发光(PL)光谱技术,结合光谱学分析方法,对CH_(3)NH_(3)PbBr_(3)(MAPbBr_(3))晶体粉末的功率密度和温度相关的光物理特性进行了研究。在405 nm连续激光激发下,PL发射峰位在560 nm,半高全宽为123 meV。光谱实验结果表明,通过... 详细信息

采用稳态光致发光(PL)光谱技术,结合光谱学分析方法,对CH_(3)NH_(3)PbBr_(3)(MAPbBr_(3))晶体粉末的功率密度和温度相关的光物理特性进行了研究。在405 nm连续激光激发下,PL发射峰位在560 nm,半高全宽为123 meV。光谱实验结果表明,通过对功率密度与PL强度进行拟合,其斜率为1.10,这很好地证明了单光子吸收的存在。在80~310 k温度范围内,MAPbBr_(3)晶体粉末的荧光峰位表现出不同的温度依赖行为。随着温度的升高,激子-声子相互作用的增强,峰宽均匀展宽,积分强度逐渐减小。PL发射峰位在80~145 k出现蓝移。在150 k附近PL发射峰出现跳跃,而当温度超过150 k时,光谱的峰位几乎保持不变。这些温度相关的PL行为主要是由于在150 k左右发生了从正交相到四方相的结构相变。此外,从温度相关的PL实验数据拟合得到激子结合能约为49.8 meV和纵向光学声子能量约为60.4 meV。

关键词：钙钛矿 MAPbBr3 晶体粉末温度依赖光致发光

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Quantum electrodynamics experiments with colliding petawatt laser pulses

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High Power Laser Science and Engineering 2019年第1期7卷 74-81页

作者： I. C. E. Turcu B. Shen D. Neely G. Sarri k. A. Tanaka P. Mckenna S. P. D. Mangles T.-P. yu W. Luo X.-L. Zhu Y. Yin STFC Rutherford Appleton Laboratory Central Laser Facility School of Electronic Science and Engineering Nanjing University ELI-NP Extreme Light Infrastructure – Nuclear Physics National Institute of Physics and Nuclear Engineering (IFIN HH) State key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences School of Physical Science and Technology ShanghaiTech University Shanghai Normal University School of Mathematics and Physics Queen’s University Belfast SUPA Department of Physics University of Strathclyde The John Adams Institute for Accelerator Science Imperial College London Department of Physics National University of Defense Technology School of Nuclear Science and Technology University of South China key Laboratory for Laser Plasmas (MOE) School of Physics and Astronomy Shanghai Jiao Tong University

A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt(PW)and even 100 PW, capable of reaching intensities of 1023 W/cm^2 in the laser focus. These ultra-high intensities are nevertheless lower than the Schwinger intensity IS= 2.3×1029 W/cm^2 at which the theory of quantum electrodynamics(QED) predicts that a large part of the energy of the laser photons will be transformed to hard Gamma-ray photons and even to matter, via electron–positron pair production. To enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding PW laser pulses is being adopted. Theoretical simulations predict strong QED effects with colliding laser pulses of 10 PW focused to intensities 10^(22) W/cm^2.

关键词： colliding petawatt laser pulses electron-positron pairs creation nonlinear Breit-Wheeler process petawatt laser facilities quantum electrodynamics

将简单序列重复标记结合到菜豆的一个分子连锁图中

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国外作物育种 2001年第4期20卷 91-92页

作者：向平 k.yu 等

Deubiquitination of BES1 by UBP12/UBP13 promotes brassinosteroid signaling and plant growth

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Plant Communications 2022年第5期3卷 171-185页

作者： Su-Hyun Park Jin Seo Jeong yu Zhou Nur Fatimah Binte Mustafa Nam-Hai Chua Temasek Life Sciences Laboratory National University of Singapore1 Research LinkSingapore 117604Singapore Present address:Wilmar International Limited 28 Biopolis RoadSingapore 138568Singapore

As a key transcription factor in the brassinosteroid (BR) signaling pathway, the activity and expression ofBES1 (BRI1-EMS-SUPPRESSOR 1) are stringently regulated. BES1 degradation is mediated by ubiquitinrelated 26S proteasomal and autophagy pathways, which attenuate and terminate BR signaling;however,the opposing deubiquitinases (DUBs) are still unknown. Here, we showed that the ubp12-2w/13-3 doublemutant phenocopies the BR-deficient dwarf mutant, suggesting that the two DUBs UBP12/UBP13 antagonize ubiquitin-mediated degradation to stabilize BES1. These two DUBs can trim tetraubiquitin with k46 and k63 linkages in vitro. UBP12/BES1 and UBP13/BES1 complexes are localized in bothcytosol and nuclei. UBP12/13 can deubiquitinate polyubiquitinated BES1 in vitro and in planta, andUBP12 interacts with and deubiquitinates both inactive, phosphorylated BES1 and active, dephosphorylated BES1 in vivo. UBP12 overexpression in BES1OE plants significantly enhances cell elongation in hypocotyls and petioles and increases the ratio of leaf length to width compared with BES1OE or UBP12OE *** elongation and etiolation result from elevated BES1 levels because BES1 degradation is retardedby UBP12 in darkness or in light with BR. Protein degradation inhibitor experiments show that the majorityof BES1 can be degraded by either the proteasomal or the autophagy pathway, but a minor BES1 fractionremains pathway specific. In conclusion, UBP12/UBP13 deubiquitinate BES1 to stabilize the latter as a positive regulator for BR responses.

关键词： UBP12 UBP13 BES1 deubiquitination brassinosteroid signaling

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最轻超核的实验测量进展和前景

Science Bulletin 2023年第24期68卷 3252-3260,M0006页

作者：陈金辉董昕马余刚许长补 key Laboratory of Nuclear Physics and Ion-beam Application(Ministry of Education) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics National Natural Science Foundation of ChinaFudan UniversityShanghai 200438China Lawrence Berkeley National Laboratory Berkeley CA 94720USA Brookhaven National Laboratory Upton NY 11973USA

中子星的性质研究是物质科学的一个重要的前沿课题,可通过天文观测、重离子碰撞等不同的方式进行研究.理论物理学家预测了超子可能存在于中子星中,所以超子-核子的相互作用对描述高密度区核物质状态方程非常重要.作为超子-核子团簇的超... 详细信息

中子星的性质研究是物质科学的一个重要的前沿课题,可通过天文观测、重离子碰撞等不同的方式进行研究.理论物理学家预测了超子可能存在于中子星中,所以超子-核子的相互作用对描述高密度区核物质状态方程非常重要.作为超子-核子团簇的超核自然而然就构成了理解超子-核子相互作用的基石.实验上,近10余年来在重离子碰撞中对已知最轻超核,超氚核及反超氚核的寿命、质量和结合能的测量引起了人们对于这个主题的兴趣.在重离子碰撞中,研究人员还测量了超氚核的截面和集体流参数,这些新的测量结果也揭示了其产生机制的新特征.本文总结了超氚核的新测量结果,着重点评了重离子碰撞领域的新实验数据,并讨论这些测量结果在描述超氚核性质以及约束超子-核子相互作用理论模型的作用.

关键词： Heavy-ion collisions Hyperon-nucleon interaction Hypernuclei