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Rainbow halos occur less following implantation of extended range of vision one-piece intraocular lenses vs diffractive bifocal intraocular lenses 被引量:3
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作者 Jae-hyung Kim Youngsub Eom +5 位作者 Seo Yeon Park Soo Youn Choi Ho Sik Hwang Jun-Heon Kim Jong Suk Song Hyo Myung Kim 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第6期913-919,共7页
AIM:To evaluate clinical outcomes following implantation of an extended range of vision intraocular lens(IOL),the ZXR00,and a diffractive multifocal IOL with+2.75 diopters(D)add power,the ZKB00.METHODS:Totally 30 pati... AIM:To evaluate clinical outcomes following implantation of an extended range of vision intraocular lens(IOL),the ZXR00,and a diffractive multifocal IOL with+2.75 diopters(D)add power,the ZKB00.METHODS:Totally 30 patients who underwent either bilateral implantation of the ZXR00 IOL with intended emmetropia(ZXR00 emmetropia group:20 eyes)and intended micromonovision(ZXR00 monovision group:20 eyes),or bilateral implantation of the ZKB00 IOL with intended emmetropia(ZKB00 group:20 eyes)were included in this study.Visual acuity at 4 m,80,and 40 cm;and the types of halos(misty,fine,and rainbow)were analyzed at one and three months after surgery.RESULTS:There were no significant differences in distance visual acuity among the three groups.The mean uncorrected intermediate visual acuity was better in the ZXR00 emmetropia and monovision groups(0.02 logMAR and 0.02 logMAR,respectively)than in the ZKB00 group(0.14 logMAR).The mean uncorrected near visual acuity was worse in the ZXR00 emmetropia group(0.26 logMAR)than in the ZXR00 monovision and ZKB00 groups(0.12 logMAR and 0.10 logMAR,respectively).There was an increased incidence of rainbow halos in the ZKB00 group vs in either ZXR00 group(P=0.033).CONCLUSION:Implantation of the ZXR00 IOL with intended micromonovision provide superior visual acuity than implantation of the ZXR00 IOL with intended emmetropia.The ZXR00 IOLs tend to show a lower incidence of rainbow halos than did the ZKB00 IOL. 展开更多
关键词 halos intraocular lens diffractive bifocal MULTIFOCAL rainbow halos
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Detection of a Physical Difference between the CDM Halos in Simulation and in Nature
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作者 肖伟科 彭昌 +1 位作者 叶显锋 郝蘅 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第5期1355-1358,共4页
Numerical simulation is an important tool that is helpful for us to understand the process of structure formation in the universe. However, many simulation results of cold dark matter (CDM) halos on a small scale ar... Numerical simulation is an important tool that is helpful for us to understand the process of structure formation in the universe. However, many simulation results of cold dark matter (CDM) halos on a small scale are inconsistent with observations: the central density profile is too cuspy and there are too many substructures, Here we point out that both the problems may be connected with a hitherto unrecognized bias in the simulated halos. Although CDM halos in nature and in simulation are both virialized systems of collisionless CDM particles, gravitational encounter cannot be neglected in the simulated halos because they contain many fewer particles. We demonstrate this by two numerical experiments, showing that there is a difference on the microcosmic scale between the natural and simulated halos. The simulated halo is more akin to globular clusters where gravitational encounter is known to lead to such drastic phenomena as core collapse. Such an artificial core collapse process appears to link the two problems together in the bottom-up scenario of structure formation in the ACDM universe. The discovery of this bias also has implications on the applicability of the Jeans theorem in galactic dynamics. 展开更多
关键词 DARK-MATTER halos COSMOLOGICAL SIMULATIONS 2-BODY RELAXATION SUBSTRUCTURE GALAXIES
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An empirical model to form and evolve galaxies in dark matter halos
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作者 Shi-Jie Li You-Cai Zhang +8 位作者 Xiao-Hu Yang Hui-Yuan Wang Dylan Tweed Cheng-Ze Liu Lei Yang Feng Shi Yi Lu Wen-Tao Luo Jian-Wen Wei 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第8期113-126,共14页
Based on the star formation histories of galaxies in halos with different masses, we develop an empirical model to grow galaxies in dark matter halos. This model has very few ingredients, any of which can be associate... Based on the star formation histories of galaxies in halos with different masses, we develop an empirical model to grow galaxies in dark matter halos. This model has very few ingredients, any of which can be associated with observational data and thus be efficiently assessed. By applying this model to a very high resolution cosmological N-body simulation, we predict a number of galaxy properties that are a very good match to relevant observational data. Namely, for both centrals and satellites, the galaxy stellar mass functions up to redshift z=4 and the conditional stellar mass functions in the local universe are in good agreement with observations. In addition, the two point correlation function is well predicted in the different stellar mass ranges explored by our model. Furthermore, after applying stellar population synthesis models to our stellar composition as a function of redshift, we find that the luminosity functions in the 0.1 u,0.19, 0.1r, 0.1i and 0.1z bands agree quite well with the SDSS observational results down to an absolute magnitude at about -17.0. The SDSS conditional luminosity function itself is predicted well. Finally, the cold gas is derived from the star formation rate to predict the HI gas mass within each mock galaxy. We find a remarkably good match to observed HI-to-stellar mass ratios. These features ensure that such galaxy/gas catalogs can be used to generate reliable mock redshift surveys. 展开更多
关键词 COSMOLOGY dark matter -- galaxies: formation -- galaxies halos
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The Effect of Central Baryonic Cores in Dark Halos on the Evaluation of Strong Lensing Probabilities
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作者 JieWang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2004年第1期10-16,共7页
We present an estimate of the strong lensing probability by dark ha-los, withemphasis on the role of the baryonic matter arising purely from radiative cooling. We treat thecontribution of the cooled baryons optimistic... We present an estimate of the strong lensing probability by dark ha-los, withemphasis on the role of the baryonic matter arising purely from radiative cooling. We treat thecontribution of the cooled baryons optimistically with all the cooled baryons confined within acentral core, and including no feedback process from stellar evolution. Our two-component modelprovides a strong lensing probability that is in good agreement with the observed distribution ofmultiple images of quasars, provided that the cooled baryons are deposited within a spherical regionof radius of 0.1 times the virial radius and follow an isothermal profile. It is pointed out thatstrong lensing may be used as an additional probe of baryon physics in dark halos though this maymeanwhile complicate the test of the inner density profiles of dark matter in halos using theobserved strong lensing probability. 展开更多
关键词 cosmology: theory galaxies: halos gravitational lensing
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Constraints on ultracompact minihalos using neutrino signals from gravitino dark matter decay
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作者 Yun-Long Zheng Yu-Peng Yang +1 位作者 Ming-Zhe Li Hong-Shi Zong 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第10期1215-1220,共6页
Ultracompact dark matter minihalos (UCMHs) would be formed during the early universe if there were large density perturbations. If dark matter can decay into particles described by the standard model, such as neutri... Ultracompact dark matter minihalos (UCMHs) would be formed during the early universe if there were large density perturbations. If dark matter can decay into particles described by the standard model, such as neutrinos, these objects would become potential astrophysical sources of emission which could be detected by in- struments such as IceCube. In this paper, we investigate neutrino signals from nearby UCMHs due to gravitino dark matter decay and compare these signals with the back- ground neutrino flux which is mainly from the atmosphere to obtain constraints on the abundance of UCMHs. 展开更多
关键词 dark matter -- early universe -- dark matter halos
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A Remark on Using Gravitational Lensing Probability as a Probe of the Central Regions of CDM Halos
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作者 YunLiNational Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2002年第5期399-407,共9页
We calculate the gravitational lensing probabilities by cold dark matter (CDM) halos with different density profiles, and compare them with current observations from the Cosmic Lens All-Sky Survey (CLASS) and the Jodr... We calculate the gravitational lensing probabilities by cold dark matter (CDM) halos with different density profiles, and compare them with current observations from the Cosmic Lens All-Sky Survey (CLASS) and the Jodrell-Bank VLA Astrometric Survey (JVAS). We find that the lensing probability is dramatically sensitive to the clumping of the dark matter, or quantitatively, the concentration parameter. We also find that our predicted lensing probabilities in most cases show inconsistency with the observations. It is argued that high lensing probability may not be an effective tool for probing the statistical properties of inner structures of dark matter halos. 展开更多
关键词 cosmology: dark matter - gravitational lensing - cosmology:theory - galaxies: halos
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北美最大柑橘包装厂投入运营 Halos桔子欲试水中国市场
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作者 张洪胜 《烟台果树》 2016年第2期47-48,共2页
国际果蔬报道获悉,北美地区最大的柑橘包装厂——Wonderful Citrus公司的Halos包装厂已投入使用,主要用于包装易剥皮的桔子。该包装厂位于加州,毗邻原有的橙子和柠檬包装厂,占地面积65万平方英尺,相当于近11个足球场的大小。这为当地提... 国际果蔬报道获悉,北美地区最大的柑橘包装厂——Wonderful Citrus公司的Halos包装厂已投入使用,主要用于包装易剥皮的桔子。该包装厂位于加州,毗邻原有的橙子和柠檬包装厂,占地面积65万平方英尺,相当于近11个足球场的大小。这为当地提供了近500个工作岗位。它还是美国最大的太阳能屋顶商业工厂,并同时拥有堪称完美的冷链设施。 展开更多
关键词 包装厂 halos CITRUS 太阳能屋顶 中国市场 占地面积 冷链 工作岗位 试水 销售总监
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Halos of Plastic
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作者 Maya Reid 《ChinAfrica》 2012年第4期52-52,共1页
The halos that span South africa’s coastline are anything but angelic. Fanning out around four major urban centers-Cape Town, Port Elizabeth, East London and durban-they are made up of innumerable bits and pieces of ... The halos that span South africa’s coastline are anything but angelic. Fanning out around four major urban centers-Cape Town, Port Elizabeth, East London and durban-they are made up of innumerable bits and pieces of plastic. as a form of pollu 展开更多
关键词 In halos of Plastic
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Geochemical Characteristics and Zonation of Primary Halos of Pulang Porphyry Copper Deposit,Northwestern Yunnan Province,Southwestern China 被引量:11
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作者 陈永清 黄静宁 梁贞 《Journal of China University of Geosciences》 SCIE CSCD 2008年第4期371-377,共7页
The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large c... The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large copper deposit. Compared with the composition of granodiorite in China, the porphyry rocks in this area are enriched in W, Mo, Cu, Au, As, Sb, F, V, and Na2O (K1≥1.2). Compared with the composition of fresh porphyry rocks in this district, the mineralized rocks are enriched in Cu, Au, Ag, Mo, Pb, Zn, W, As, Sb, and K2O (K2≥1.2). Some elements show clear anomalies, such as Zn, Ag, Cu, Au, W, and Mo, and can be regarded as pathfinders for prospecting new ore bodies in depth. It has been inferred from factor analysis that the Pulang porphyry copper deposit may have undergone the multiple stages of alteration and mineralization: (a) Cu-Au mineralization; (b) W-Mo mineralization; and (c) silicification and potassic metasomatism in the whole ore-forming process. A detailed zonation sequence of indicator elements is obtained using the variability index of indicator elements as follows: Zn→Ag→Cu→Au→W→Mo. According to this zonation, an index such as (Ag*Zn)D/(Mo×W)D can be constructed and regarded as a significant criterion for predicting the Cu potential at a particular depth. 展开更多
关键词 Pulang porphyry copper deposit zonation of primary halo assessment of Cu potential at depth Tethys-Himalaya ore-forming domain southwestern China
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Neutron Halos in the Excited States of Spherical Nuclei Near the β-Stable Line 被引量:2
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作者 REN Zhong-Zhou JIANG Wei-Zhou CAI Xiang-Zhou ZHU Zhi-Yuan SHEN Wen-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第10期470-474,共5页
The newly discovered neutron halos in the excited states of nuclei 12B, 13C, and 209pb are studied by therelativistic mean-field theory. The calculated binding energies are very close to the experimental ones. The exp... The newly discovered neutron halos in the excited states of nuclei 12B, 13C, and 209pb are studied by therelativistic mean-field theory. The calculated binding energies are very close to the experimental ones. The experimentally extracted root-mean-square radii of the last neutron with different occupations in nuclei are well reproduced bycalculations. New candidates for the neutron halos in excited states are predicted and are useful for further search ofneutron halos in the excited states of stable nuclei. 展开更多
关键词 NEUTRON halo EXCITED states RELATIVISTIC MEAN-FIELD theory
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Pairwise Velocity Statistics of Dark Halos
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作者 Hai-YanZhangt Yi-PengJing 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2004年第6期507-517,共11页
We have accurately evaluated the halo pairwise velocity dispersion and the halo mean streaming velocity in the LCDM model (the fiat ω0 = 0.3 model) using a set of high-resolution N-body simulations. Based on the simu... We have accurately evaluated the halo pairwise velocity dispersion and the halo mean streaming velocity in the LCDM model (the fiat ω0 = 0.3 model) using a set of high-resolution N-body simulations. Based on the simulation results, we have developed a model for the pairwise velocity dispersion of halos. Our model agrees with the simulation results over all scales we studied. We have also tested the model of Sheth et al. for the mean streaming motion of halos derived from the pair-conservation equation. We found that their model reproduces the simulation data very well on large scale, but under-predicts the streaming motion on scales r < 10 h-1 Mpc. We have introduced an empirical relation to improve their model. These improved models are useful for predicting the redshift correlation functions and the redshift power spectrum of galaxies if the halo occupation number model, e.g. the cluster weighted model, is given for the galaxies. 展开更多
关键词 cosmology: theory - dark matter halo - large-scale structure of universe
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Searching the Parameters of Dark Matter Halos on the Basis of Dwarf Galaxies’ Dynamics
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作者 L. M. Chechin T. K. Konysbayev 《Journal of Modern Physics》 2016年第9期982-988,共7页
Article devoted to searching the parameters of dark matter halos on the base of dwarf galaxies’ dynamics (Messier 32 and Leo I). For doing this, we propose the new approach founded on construction the coupled ellipti... Article devoted to searching the parameters of dark matter halos on the base of dwarf galaxies’ dynamics (Messier 32 and Leo I). For doing this, we propose the new approach founded on construction the coupled elliptical trajectory for a probe body in the gravitational fields of Newtonian potential and potential of dark matter’s halo. This allows more accuracy estimate its central density for the Navarro-Frenk-White profile and free parameter for the Einasto profile . Our result is in good correlation with results of other authors that are got by different numerical methods. 展开更多
关键词 Dwarf Galaxies Dark Matter Halo Central Density of Dark Matter Profile Parameters of Dark Matter’s Halo
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大气重力波影响中高层sprite halos始发位置和光辐射形态的模拟研究 被引量:1
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作者 张金波 张其林 +2 位作者 郭秀峰 侯文豪 郜海阳 《中国科学:地球科学》 CSCD 北大核心 2019年第6期1024-1036,共13页
目前关于重力波和中高层大气放电现象之间的相关性问题,在同步观测和数值模拟研究方面都较少,为了研究大气重力波对TLEs的调制效应,建立了三维对流层-中高层大气准静电场耦合效应模式,模拟分析了重力波导致的中高层大气密度(包括中性空... 目前关于重力波和中高层大气放电现象之间的相关性问题,在同步观测和数值模拟研究方面都较少,为了研究大气重力波对TLEs的调制效应,建立了三维对流层-中高层大气准静电场耦合效应模式,模拟分析了重力波导致的中高层大气密度(包括中性空气密度和电子密度)不均匀对中高层sprite halos(闪晕)始发位置和光辐射形态的影响.结果表明,重力波扰动导致低电离层大气密度分布不均匀,在重力波波谷位置的空气更易被击穿,使得sprite halos在重力波波谷位置更容易始发.同时,重力波扰动会导致sprite halos光辐射形态产生变形,强发光区主要沿波谷位置分布,波峰位置的光强相对较弱,重力波扰动幅值越大,对sprite halos光辐射形态的影响越大;而对流层闪电强度越大,光辐射空间分布受重力波的影响越小;此外,观测到的sprite halos光辐射的强度和形态特征还会受到观测方位的影响. 展开更多
关键词 三维准静电场模型 SPRITE halos 光辐射 重力波
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地月周期轨道对地月L1与L2附近Halo轨道的可见性分析
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作者 李星明 果琳丽 +3 位作者 伏瑞敏 郑国宪 王培培 董联庆 《航天返回与遥感》 CSCD 北大核心 2024年第2期53-65,共13页
随着去往月球航天器的增多,现有的近地空间光学卫星与地基光学望远镜的探测能力已无法满足要求,急需增强地月空间观测能力,通过使用地月周期轨道来填补地月空间观测能力的不足被认为是一种有效手段。针对地月周期轨道的特性,文章基于微... 随着去往月球航天器的增多,现有的近地空间光学卫星与地基光学望远镜的探测能力已无法满足要求,急需增强地月空间观测能力,通过使用地月周期轨道来填补地月空间观测能力的不足被认为是一种有效手段。针对地月周期轨道的特性,文章基于微分校正原理对三体轨道建模,并完成了算法的设计,提出了地月周期轨道的选择原则,并优选了3条轨道。在地月周期轨道对地月拉格朗日点L1、L2附近Halo轨道的可见性分析中,为方便评估,采用类球体的物体星等评估模型来定义可见性的评估标准;基于卫星工具包提供模型计算中涉及的自然天体、物体和观测卫星三者的时空关系,给出了可见性分析过程及结果,研究表明地月周期轨道对地月拉格朗日点L1、L2附近Halo轨道均有不错的观测效果,其中轨道1对地月周期轨道的可见性综合最高,均大于95%。 展开更多
关键词 地月周期轨道 微分校正 HALO轨道 星等模型 可见性 空间探测
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微流星体碰撞对日地L_(2)点Halo轨道的影响
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作者 李庆军 吴雨亭 +3 位作者 王博 霍卓玺 刘冀林 刘慧根 《动力学与控制学报》 2024年第6期16-23,共8页
空间中存在大量高速运动的微流星体,与在轨运行的航天器发生碰撞后将导致轨道偏离、性能下降、结构破坏甚至航天器失效.由于Halo轨道具有不稳定的特性,本文主要探究微流星体碰撞对日地L_(2)点Halo轨道动力学演化规律的影响.首先,建立日... 空间中存在大量高速运动的微流星体,与在轨运行的航天器发生碰撞后将导致轨道偏离、性能下降、结构破坏甚至航天器失效.由于Halo轨道具有不稳定的特性,本文主要探究微流星体碰撞对日地L_(2)点Halo轨道动力学演化规律的影响.首先,建立日地L_(2)点附近轨道的动力学模型,通过微分修正法构造Halo轨道的初始条件,基于Grün微流星体通量模型计算微流星体与航天器碰撞的数量和碰撞引起的速度改变量.然后,采用Runge-Kutta算法求解Halo轨道的动力学方程,研究碰撞速度改变量引起的轨道偏差随时间的演化规律.此外,采用状态转移矩阵方法分析初始状态偏差的演化规律,并与数值积分方法对比.最后基于状态转移矩阵方法分析了不同碰撞速度改变量的大小和方向引起的动力学响应.研究发现,状态转移矩阵在短时间内得到的结果与数值积分方法基本一致,而且只需一次矩阵乘法即可通过初始状态偏差计算得到末时刻状态偏差,具有非常高的效率.研究结果表明,由于Halo轨道固有的不稳定特性,所以初始时刻微流星体碰撞引起的微小状态偏差会快速增长,导致消耗更多控制燃料,最终将影响航天器的寿命.此外,微流星体碰撞的速度改变量的方向对偏差传递的规律有重要的影响. 展开更多
关键词 微流星体碰撞 HALO轨道 状态转移矩阵 太空望远镜
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Simulated impacts of atmospheric gravity waves on the initiation and optical emissions of sprite halos in the mesosphere 被引量:1
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作者 Jinbo ZHANG Qilin ZHANG +2 位作者 Xiufeng GUO Wenhao HOU Haiyang GAO 《Science China Earth Sciences》 SCIE EI CAS CSCD 2019年第4期631-642,共12页
The correlation between atmospheric gravity waves(GWs) and Transient Luminous Events(TLEs) has been poorly studied using both synchronous observations and numerical simulations. To investigate the modulation effects o... The correlation between atmospheric gravity waves(GWs) and Transient Luminous Events(TLEs) has been poorly studied using both synchronous observations and numerical simulations. To investigate the modulation effects of GWs on TLEs,a troposphere-mesosphere quasi-electrostatic field model is developed in three-dimensional Cartesian coordinates, and the effects of GW perturbations on the initiation and optical emissions of sprite halos are simulated using the model. Simulation results indicate that the atmospheric density at lower ionosphere altitudes becomes inhomogeneous due to GW perturbations, and sprite halos tend to initiate in the GW troughs due to the lower electric breakdown threshold. GW perturbations cause the deformation of sprite halos, strong luminous regions distribute mainly along the GW troughs while optical intensities along the GW peaks is relatively weak. Larger GW perturbations lead to more pronounced deformation of sprite halos, however, stronger lightning discharges in the troposphere result in less optical perturbations of sprite halos. The observed luminous intensities and optical morphology of sprite halos are also affected by the observing orientations and the lightning polarities. 展开更多
关键词 Three-dimensional quasi-electrostatic field model SPRITE halos Optical emission GRAVITY waves
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最佳Halo重力牵引治疗Lenke3型脊柱侧凸的生物力学分析
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作者 富荣昌 杨骁峥 李现政 《中国组织工程研究》 CAS 北大核心 2024年第18期2901-2905,共5页
背景:Halo重力牵引是许多学者认可的术前牵引方法,但大部分为临床观察,缺乏有限元的相关分析。目的:运用有限元法探究Halo重力牵引对Lenke3型脊柱侧凸的最佳牵引力,从生物力学角度为临床提供理论依据。方法:对脊柱侧凸患者扫描的CT图像... 背景:Halo重力牵引是许多学者认可的术前牵引方法,但大部分为临床观察,缺乏有限元的相关分析。目的:运用有限元法探究Halo重力牵引对Lenke3型脊柱侧凸的最佳牵引力,从生物力学角度为临床提供理论依据。方法:对脊柱侧凸患者扫描的CT图像进行逆向建模处理并建立有限元模型,并取正常节段(T1-T4椎体)对模型的有效性进行验证。对腰胸椎侧凸模型设置5组不同的受力条件,模拟患者在不同牵引力作用下的矫正情况。5组皆将L5下表面完全约束,在T1上表面施加沿Z轴正方向(重力的反方向)不同大小的牵引力,分别为50,100,150,200,250 N。对比不同牵引力下侧凸脊柱的位移、主弯曲的Cobb角变化情况、脊柱的伸长量以及Von Mises应力。结果与结论:①当Halo重力牵引力为150-200 N时,主弯曲的Cobb角缩小量为最大缩小量的69.4%-88.9%,Z轴的伸长量是最大伸长量69.4%-85.9%,受到的应力为最大应力的63.6%-82.9%;②牵引力大于200 N,Cobb角的减少量和Z轴的伸长量变化不明显,但应力值急剧增长,且此时的T6、T7、T8椎体质心到L5中垂线的减小距离最为明显;③当Halo重力牵引力为150-200 N时,对此类型患者的矫正效果最佳——Cobb角缩小量与Z轴伸长量效果较佳的同时不会有应力的急剧增长。上述结果可为临床矫正提供一定的理论支持,可在较大程度矫正侧凸时保证患者安全。 展开更多
关键词 脊椎侧凸 Halo重力牵引 COBB角 有限元
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改良Halo骨盆牵引对重度脊柱畸形伴呼吸功能障碍患者的干预效果
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作者 杨云飞 黄立军 +5 位作者 夏庆福 张玉双 赵国峰 夏纪元 田新奇 刘畅 《河北医药》 CAS 2024年第11期1642-1646,共5页
目的探讨一期改良Halo骨盆牵引(halo-pelvic traction,HPT)联合二期手术对重度脊柱畸形伴呼吸功能障碍患者的应用效果。方法选取2019年1月至2022年1月北京大望路急诊抢救医院收治的120例重度脊柱畸形伴呼吸功能障碍患者作为研究对象。... 目的探讨一期改良Halo骨盆牵引(halo-pelvic traction,HPT)联合二期手术对重度脊柱畸形伴呼吸功能障碍患者的应用效果。方法选取2019年1月至2022年1月北京大望路急诊抢救医院收治的120例重度脊柱畸形伴呼吸功能障碍患者作为研究对象。所有患者均行一期HPT牵引治疗和二期脊柱畸形矫形术。牵引前、牵引末次复查、内固定术后、末次随访,比较患者影像学指标和呼吸功能指标的变化情况。结果牵引前,患者主弯侧凸Cobb角、颈7铅垂线至骶骨正中线的距离(C7PL-CSVL)、顶椎偏距(AVT)、T1倾斜角、影像学肩高度、矢状面偏移(SVA)、腰胸椎后凸角(TK)为(119.17±15.39)°、(33.33±7.2)mm、(103.55±16.56)mm、(20.13±5.94)°、(26.78±6.32)mm、(38.29±5.54)mm、(87.66±11.63)°,高于牵引末次复查[(74.62±15.15)°、(13.23±4.27)mm、(57.70±17.56)mm、(9.29±1.73)°、(10.18±2.00)mm、(14.41±3.24)mm、(52.96±12.11)°]、内固定术后[(60.78±14.40)°、(12.42±3.58)mm、(44.31±13.77)mm、(8.89±2.66)°、(9.38±2.39)mm、(17.11±3.24)mm、(51.28±11.20)°]和末次随访[(64.21±14.86)°、(12.69±3.26)mm、(45.17±11.65)mm、(6.51±1.77)°、(9.53±2.36)mm、(17.50±3.07)mm、(51.82±12.20)°],差异有统计学意义(P<0.01)。牵引前,患者FVC、FVC%、FEV1、FEV1%为(1.13±0.19)L、(31.61±4.64)%、(1.08±0.22)L、(29.68±11.56)%,低于牵引末次复查[(1.36±0.28)L、(36.19±4.95)%、(1.17±0.19)L、(33.45±5.97)%]、内固定术后[(1.49±0.28)L、(38.08±7.46)%、(1.26±0.22)L、(35.91±7.81)%]和末次随访[(1.53±0.26)L、(38.61±6.91)%、(1.28±0.24)L、(36.88±7.85)%],差异有统计学意义(P<0.01)。结论改良HPT牵引能有效矫正重度脊柱畸形伴呼吸功能障碍患脊柱畸形,改善呼吸功能,是一种安全、有效地辅助治疗措施。 展开更多
关键词 Halo骨盆牵引 改良 呼吸功能障碍 重度脊柱畸形
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Halo-骨盆牵引治疗重度脊柱侧弯畸形的效果及其对肺功能的影响
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作者 夏纪元 杨云飞 +2 位作者 黄立军 夏庆福 张玉双 《武警医学》 CAS 2024年第3期230-234,共5页
目的探讨Halo-骨盆牵引(HPT)治疗重度脊柱侧弯畸形的效果及其对肺功能的影响。方法回顾性分析2021-01至2023-10北京大望路急诊抢救医院收治的100例脊柱侧弯合并肺功能不全患者的临床资料作为研究对象,所有患者均行一期HPT牵引治疗和二... 目的探讨Halo-骨盆牵引(HPT)治疗重度脊柱侧弯畸形的效果及其对肺功能的影响。方法回顾性分析2021-01至2023-10北京大望路急诊抢救医院收治的100例脊柱侧弯合并肺功能不全患者的临床资料作为研究对象,所有患者均行一期HPT牵引治疗和二期脊柱侧弯矫形术。牵引前、牵引末次复查、内固定术后,比较患者影像学指标和肺功能指标的变化情况。采用Pearson统计学相关性分析主弯Cobb角对肺功能指标的影响。结果纳入患者肺功能结果显示,牵引前、牵引末次复查、内固定术后比较,限制性通气功能参数均存在不同程度增高(P<0.05)。相关分析表明,随着主弯Cobb角减小,肺限制性通气功能参数呈显著负相关性(P<0.05)。结论HPT牵引能有效矫正重度脊柱侧弯畸形,改善呼吸功能,是一种安全、有效的辅助治疗措施。 展开更多
关键词 Halo骨盆牵引 肺功能不全 重度脊柱畸形
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Statistical Study of the Geoeffectivity of Halo Coronal Mass Ejections Associated with X-Class Flares during Solar Cycles 23 and 24
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作者 Younoussa Diakite Christian Zoundi +1 位作者 M’Bi Kabore Jean Louis Zerbo 《Open Journal of Applied Sciences》 2024年第4期950-960,共11页
By analysing a long series of data (1996-2019), we show that solar cycle 23 was more marked by violent solar flares and coronal mass ejections (CMEs) compared to solar cycle 24. In particular, the halo coronal mass ej... By analysing a long series of data (1996-2019), we show that solar cycle 23 was more marked by violent solar flares and coronal mass ejections (CMEs) compared to solar cycle 24. In particular, the halo coronal mass ejections associated with X-class flares appear to be among the most energetic events in solar activity given the size of the flares, the speed of the CMEs and the intense geomagnetic storms they produce. Out of eighty-six (86) X-class halo CMEs, thirty-seven (37) or 43% are highly geoeffective;twenty-four (24) or approximately 28% are moderately geoeffective and twenty-five (25) or 29% are not geoeffective. Over the two solar cycles (1996 to 2019), 71% of storms were geoeffective and 29% were not. For solar cycle 23, about 78% of storms were geoeffective, while for solar cycle 24, about 56% were geoeffective. For the statistical study based on speed, 85 halo CMEs associated with X-class flares were selected because the CME of 6 December 2006 has no recorded speed value. For both solar cycles, 75.29% of the halo CMEs associated with X-class flares have a speed greater than 1000 km/s. The study showed that 42.18% of halo (X) CMEs with speeds above 1000 km/s could cause intense geomagnetic disturbances. These results show the contribution (in terms of speed) of each class of halo (X) CMEs to the perturbation of the Earth’s magnetic field. Coronal mass ejections then become one of the key indicators of solar activity, especially as they affect the Earth. 展开更多
关键词 CME Halo (X) Geoeffectivity Geomagnetic Storm Solar Flare Solar Cycle
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