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中国经济增长模型的设定:1952—1998 被引量:133
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作者 舒元 徐现祥 《经济研究》 CSSCI 北大核心 2002年第11期3-11,63,共10页
现代经济增长理论能够刻画我国的经济增长吗 ?如果能 ,那么哪类经济增长理论能比较好地刻画我国的经济增长呢 ?围绕这些问题 ,本文从实证和理论两个方面展开讨论。在实证上 ,本文采用Jones( 1 995)实证检验新增长理论的方法 ,针对各类... 现代经济增长理论能够刻画我国的经济增长吗 ?如果能 ,那么哪类经济增长理论能比较好地刻画我国的经济增长呢 ?围绕这些问题 ,本文从实证和理论两个方面展开讨论。在实证上 ,本文采用Jones( 1 995)实证检验新增长理论的方法 ,针对各类经济增长理论的核心特征 ,实证分析了 1 952— 1 998年间我国经济增长的典型事实 ,结果发现这些典型事实明显地拒绝了新古典增长理论和R&D类型增长理论 ,相对而言 ,比较支持AK类型增长理论。另外 ,我们还发现以综合要素生产率测量的技术进步 ,不是我国1 952—1 998年间经济增长的引擎。在理论上 ,本文从“边干边学”的角度 ,把“探索适合我国国情的经济建设道路”纳入经济增长模型 ,证明了其本身可以作为我国经济增长的引擎 ;同时回答了为什么AK类型增长理论能够刻画我国的经济增长。 展开更多
关键词 经济增长 AK类型增长模型 中国 实证分析 R&D类型增长理论 jones 新古典增长理论
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早孕期产前超声诊断进展 被引量:22
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作者 李胜利 文华轩 《中华妇幼临床医学杂志(电子版)》 CAS 2011年第4期229-232,共4页
近年早孕期产前诊断越来越被临床所重视。随着实践与经验以及超声仪器分辨率的不断提高,使早孕期超声检查胎儿结构、筛查胎儿畸形成为可能。Michailidis等^[1]研究发现,使用二维超声检查,93.7%胎儿的完整解剖学结构能在早孕期得... 近年早孕期产前诊断越来越被临床所重视。随着实践与经验以及超声仪器分辨率的不断提高,使早孕期超声检查胎儿结构、筛查胎儿畸形成为可能。Michailidis等^[1]研究发现,使用二维超声检查,93.7%胎儿的完整解剖学结构能在早孕期得到显示。Jones等^[2]认为,超过80%胎儿畸形在12孕周前已有表现。 展开更多
关键词 产前超声诊断 早孕期 解剖学结构 胎儿畸形 孕期超声检查 二维超声检查 jones 产前诊断
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结膜囊成形术的研究进展 被引量:15
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作者 刘静 廖洪斐 《中国实用眼科杂志》 CSCD 北大核心 2006年第11期1108-1111,共4页
关键词 结膜囊成形术 结膜囊狭窄 结膜囊闭锁 眼窝再造术 手术矫正 正常结膜囊 jones 国内外研究
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蜘蛛香中绿原酸及总酚酸的含量测定 被引量:12
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作者 刘开萍 杨军 +3 位作者 罗喜荣 赵开坤 尹航 刘兴赋 《湖北农业科学》 2017年第2期288-290,共3页
试验建立了蜘蛛香(Valeriana jatamansi Jones)中绿原酸和总酚酸的含量测定方法。利用高效液相色谱法(HPLC)测定蜘蛛香中绿原酸的含量,色谱柱为Dikma C_(18)(4.6 mm×250 mm,5μm),流动相为乙腈-0.4%磷酸水溶液(12∶88),流速1.0 mL/... 试验建立了蜘蛛香(Valeriana jatamansi Jones)中绿原酸和总酚酸的含量测定方法。利用高效液相色谱法(HPLC)测定蜘蛛香中绿原酸的含量,色谱柱为Dikma C_(18)(4.6 mm×250 mm,5μm),流动相为乙腈-0.4%磷酸水溶液(12∶88),流速1.0 mL/min,检测波长327 nm,柱温30℃;以绿原酸为对照品,采用紫外-可见分光光度法(UV)在327 nm波长处测定蜘蛛香中总酚酸的含量。结果表明,绿原酸在2~20μg/mL范围内浓度与峰面积线性关系良好,r=0.999 6,加样回收率为97.95%,RSD为1.37%;总酚酸在5~20μg/mL范围内浓度与吸光度线性关系良好,r=0.999 8,加样回收率为100.31%,RSD为1.34%。该方法简便、快速、准确、重复性好,可用于蜘蛛香中绿原酸和总酚酸的含量测定。 展开更多
关键词 蜘蛛香(Valeriana jatamansi jones) 绿原酸 总酚酸
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重症快速反应小组的构建 被引量:11
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作者 JohnA.Kellum 张继承 《中华内科杂志》 CAS CSCD 北大核心 2012年第8期595-596,共2页
医院里大部分重症或不稳定患者都收在ICU,但大部分意外死亡病例发生在ICU外,也就是普通病房。有研究显示,严重不良事件主要发生在各种原因导致的抢救失败后。Jones等^[1]回顾分析了有关快速反应系统的研究,并评估其效果。结果表明... 医院里大部分重症或不稳定患者都收在ICU,但大部分意外死亡病例发生在ICU外,也就是普通病房。有研究显示,严重不良事件主要发生在各种原因导致的抢救失败后。Jones等^[1]回顾分析了有关快速反应系统的研究,并评估其效果。结果表明,亟须提高运用快速反应系统的能力,将患者快速转入ICU,赢得最佳治疗时间,得到最佳治疗。 展开更多
关键词 快速反应系统 重症 最佳治疗时间 jones ICU 死亡病例 普通病房 不良事件
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Anti-anxiety effect of Valeriana jatamansi Jones extract via regulation of the hypothalamus-pituitary-adrenal axis 被引量:9
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作者 Zhiyong Yan Tian'e Zhang +4 位作者 Ting Xiao Lingzhen Pan Jinzhi Qin Zhanping Zhang Changying Zuo 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第14期1071-1075,共5页
BACKGROUND: Hypothalamus-pituitary-adrenal (HPA) axis dysfunction has been closely linked to anxiety. Previous studies have shown that Valeriana jatamansi Jones extract exhibits clear anxiolytic effects, but it is ... BACKGROUND: Hypothalamus-pituitary-adrenal (HPA) axis dysfunction has been closely linked to anxiety. Previous studies have shown that Valeriana jatamansi Jones extract exhibits clear anxiolytic effects, but it is unclear about the mechanism underlying regulation of the HPA axis dysfunction in these anxiolytic effects. OBJECTIVE: To observe the effects of Valeriana jatamansi Jones (Zhizhu Xiang) extract on HPA axis function in a rat model of anxiety, and to compare these effects with positive control estazolam. DESIGN, TIME AND SETTING: Randomized, controlled, animal experiment was performed at Chengdu University of Traditional Chinese Medicine, China, between February and September in 2006. MATERIALS: Estazolam was purchased from Shanghai Jiufu Pharmaceutical, China; Valeriana jatamansiJones was purchased from the Lotus Pond Market for Chinese Herbal Medicine in Chengdu. It consisted of iridoids and flavonoid components. METHODS: A total of 72 Sprague Dawley rats, aged 2 months, were randomly assigned to 6 groups low-, medium-, and high-dose Valerianajatamansi Jones groups intragastrically injected with 0.3, 0.6, and 0.9 g/kg per day Valerianajatamansi Jones extract, respectively; estazolam group intragastrically injected with 1.5 mg/kg per day estazolam; model and normal groups administered 5 mL physiological saline. Anxiety was established in all groups, except the normal group, through the use of elevated plus-maze test at 7 days following drug administration. MAIN OUTCOME MEASURES: Blood β-endorphin and corticosterone levels were determined using enzyme-linked immunosorbent assay following treatment with ValerianajatamansiJones extract. Expressions of HPA axis-related genes were measured by cDNA microarray. RESULTS: Blood β-endorphin and corticosterone levels were significantly greater in the model group than in the normal group. Compared with the model group, levels decreased with Valeriana jatamansi Jones extract or estazolam treatment, particularly in the low-dose Valeriana jataman 展开更多
关键词 ANXIETY Valeriana jatamansi jones hypothalamus-pituitary-adrenal axis RATS
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Geometric and physical configurations of meta-atoms for advanced metasurface holography 被引量:10
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作者 Joohoon Kim Younghwan Yang +3 位作者 Trevon Badloe Inki Kim Gwanho Yoon Junsuk Rho 《InfoMat》 SCIE CAS 2021年第7期739-754,共16页
Metasurfaces consisting of subwavelength structures,so-called meta-atoms,have steadily attracted considerable attention for advanced holography due to their advantages in terms of high-resolution holographic images,la... Metasurfaces consisting of subwavelength structures,so-called meta-atoms,have steadily attracted considerable attention for advanced holography due to their advantages in terms of high-resolution holographic images,large field of view,and compact device volume.In contrast to conventional holographic displays using bulky conventional diffractive optical elements,metasurface holography enables arbitrary complex wavefront shaping with a much smaller footprint.In this review,we classify metasurface holography according to the meta-atom design methodologies,which can further expand hologram functionalities.We describe light-matter interactions,particularly in metasurface systems,using the relevant the Jones matrix to rigorously explain modulations of the amplitude,phase,and polarization of light.Six different types of metaatoms are presented,and the corresponding achievable wavefronts that form the holographic images in the far-field are also provided.Such a simple classification will give a straightforward approach to design and further realize advanced metasurface holographic devices. 展开更多
关键词 jones calculus meta-atom metahologram METAMATERIAL metasurface
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动力髋螺钉内固定与人工股骨头置换术治疗高龄股骨转子间骨折的疗效分析 被引量:10
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作者 夏远军 章莹 +3 位作者 章凯 尹庆水 吴文 谢会斌 《中华创伤骨科杂志》 CAS CSCD 2009年第9期895-896,共2页
股骨转子间骨折是多发于老年人的骨折,因为老年人常伴有骨质疏松,且多合并内科疾病,全身情况较差,所以股骨转子间骨折围手术期的死亡率一直较高,伤后3个月内患者的死亡率约为16.7%。近年来,常用的手术方法有动力髋螺钉(dynamic... 股骨转子间骨折是多发于老年人的骨折,因为老年人常伴有骨质疏松,且多合并内科疾病,全身情况较差,所以股骨转子间骨折围手术期的死亡率一直较高,伤后3个月内患者的死亡率约为16.7%。近年来,常用的手术方法有动力髋螺钉(dynamic hip screw,DHS)内固定和人工股骨头置换术等。回顾我院自2004年1月至2008年8月采用以上两种方法治疗且获得随访的高龄股骨转子间Jones—Evens分型Ⅲ型骨折58例患者的病历资料,报告如下。 展开更多
关键词 动力髋螺钉内固定 股骨转子间骨折 人工股骨头置换术 疗效分析 治疗 jones 骨质疏松 内科疾病
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Conversion between polarization states based on a metasurface 被引量:9
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作者 SHUYUN TENG QI ZHANG +2 位作者 HAN WANG LIXIA LIU HAORAN LV 《Photonics Research》 SCIE EI CSCD 2019年第3期246-250,共5页
Transmission of an anisotropic metasurface is analyzed in a polar base relying on the Jones calculus, and polarization conversion from the spatial uniform polarization to the spatial nonuniform polarization is explore... Transmission of an anisotropic metasurface is analyzed in a polar base relying on the Jones calculus, and polarization conversion from the spatial uniform polarization to the spatial nonuniform polarization is explored.Simple and compact polarization converters based on rectangular holes or cross holes etched in silver film are designed, and polarization conversions from the linear and circular polarization to the radial and azimuthal polarization are realized. Numerical simulations of three designed polarization converters consisting of rectangular holes equivalent to polarizers and quarter-and half-wave plates, exhibit the perfect polarization conversion.The experiment results consistent with the simulations verify theoretic predictions. This study is helpful for designing metasurface polarization converters and expanding the application of a metasurface in polarization manipulations. 展开更多
关键词 BETWEEN polarization STATES ANISOTROPIC metasurface jones CALCULUS
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琼斯百米决赛技术分析 被引量:7
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作者 杜少武 吉娜薇 +1 位作者 徐国根 吉沙丽 《北京体育大学学报》 CSSCI 北大核心 2001年第4期573-574,共2页
第 2 7届奥运会女子 10 0m金牌得主琼斯 ,在跑的技术有着明显的个人特点 ,其跑步技术的“前驱”性和其他技术特征上的合理性 ,向我们提示了短跑教学、训练工作应向多极化方向发展。文章用运动技术分析的方法 ,从琼丝技术特点的角度 ,对... 第 2 7届奥运会女子 10 0m金牌得主琼斯 ,在跑的技术有着明显的个人特点 ,其跑步技术的“前驱”性和其他技术特征上的合理性 ,向我们提示了短跑教学、训练工作应向多极化方向发展。文章用运动技术分析的方法 ,从琼丝技术特点的角度 ,对其跑的技术从某些侧面进行了研究。 展开更多
关键词 女子100 M 琼斯 技术 分析
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超临界CO_2萃取蜘蛛香中缬草素工艺优化 被引量:7
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作者 罗喜荣 苑天红 +1 位作者 杨军 莫彬彬 《湖北农业科学》 北大核心 2013年第8期1901-1902,1912,共3页
探讨超临界CO2萃取蜘蛛香(Valeriana jatamansi Jones.)中缬草素工艺条件的优化,采用响应曲面法考察萃取压力、萃取温度、萃取时间对缬草素收率的影响。结果表明,优化的萃取条件为萃取压力28MPa、萃取温度44℃、萃取时间49 min,此条件... 探讨超临界CO2萃取蜘蛛香(Valeriana jatamansi Jones.)中缬草素工艺条件的优化,采用响应曲面法考察萃取压力、萃取温度、萃取时间对缬草素收率的影响。结果表明,优化的萃取条件为萃取压力28MPa、萃取温度44℃、萃取时间49 min,此条件下缬草素收率为1.88%。 展开更多
关键词 蜘蛛香(Valeriana jatamansi jones ) 缬草素 超临界CO2萃取 响应曲面法
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Assessing the readability of online information about jones fracture
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作者 Khaled Farid Khaled Al-Kharouf Faisal Idrees Khan Greg AJ Robertson 《World Journal of Methodology》 2023年第5期439-445,共7页
BACKGROUND Hand in hand with technological advancements,treatment modalities continue to grow.With the turn of the century,the internet has become the number one source of information for almost every topic.Thus,many ... BACKGROUND Hand in hand with technological advancements,treatment modalities continue to grow.With the turn of the century,the internet has become the number one source of information for almost every topic.Thus,many patients look toward the internet as their primary source of information to learn about their respective medical conditions.The American Medical Association and National Institute of Health strongly recommend that online medical information be written at the 6th to 8th-grade level to aid comprehension by patients of all literacy backgrounds.AIM To assess the readability of online information regarding Jones fracture.Our hypothesis is that the reading level of medical information published on websites far exceeds the recommended reading level of 6th-8th grade as proposed by the American Medical Associate and National Institute of Health.The result of this study can help us formulate improved recommendations for publishing more comprehensible material and,thus,eventually improve patient compliance and clinical outcomes.METHODS The exact phrase“Jones fracture”was queried on the three most common search engines,Google,Yahoo!,and Bing,on December 28,2022.As of December 2022,Google held 84%,Bing held 9%,and Yahoo!held 2%of the worldwide search engine market share.Web pages uniform resource locator from the first three pages of search results were recorded from each search engine.These web pages were classified according to academic,physician-sponsored,governmental and non-government organizations(NGO),commercial,and unspecified as per formally defined categories.Websites associated with an educational institution or medical organization were classified as academic.Websites with products for sale,corporate sponsorship,or advertisements were classified as commercial.Governmental websites or NGOs comprised those that received government subsidies or grants.Webpages that were independently owned by physicians or physician groups were respectively classed as physician sponsored.The remainder of websites tha 展开更多
关键词 jones fracture jones fracture treatment jones fracture management jones fracture prevention jones fracture types jones fracture location
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下鼻甲肥厚的手术治疗 被引量:8
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作者 张兴友 单春光 《中国中西医结合耳鼻咽喉科杂志》 2008年第4期315-318,共4页
1895年Jones TC和Jones M首次报道了下鼻甲切除术,主要是为了治疗因下鼻甲肥厚而导致的鼻阻塞,以及由此引起的耳聋、耳鸣,取得了较好疗效,但此后也出现了一些不容忽视的并发症,如出血、干燥、结痂,甚或是所谓的空鼻综合征。为了... 1895年Jones TC和Jones M首次报道了下鼻甲切除术,主要是为了治疗因下鼻甲肥厚而导致的鼻阻塞,以及由此引起的耳聋、耳鸣,取得了较好疗效,但此后也出现了一些不容忽视的并发症,如出血、干燥、结痂,甚或是所谓的空鼻综合征。为了规避这些风险,一百多年来,耳鼻咽喉科医师做了不懈的努力,推出了多种下鼻甲手术方法,这正说明没有哪一种手术方法是完美的。 展开更多
关键词 下鼻甲肥厚 手术治疗 耳鼻咽喉科医师 jones 下鼻甲切除术 手术方法 空鼻综合征 鼻阻塞
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Molecular Dynamics, Physical Properties, Diffusion Coefficients and Activation Energy of the Lithium Oxide (Li-O) and Sodium Oxide (Na-O) Electrolyte (Cathode)
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作者 Alain Second Dzabana Honguelet Abel Dominique Eboungabeka Timothée Nsongo 《Advances in Materials Physics and Chemistry》 CAS 2024年第9期213-234,共22页
This work is a simulation model with the LAMMPS calculation code of an electrode based on alkali metal oxides (lithium, sodium and potassium) using the Lennard Jones potential. For a multiplicity of 8*8*8, we studied ... This work is a simulation model with the LAMMPS calculation code of an electrode based on alkali metal oxides (lithium, sodium and potassium) using the Lennard Jones potential. For a multiplicity of 8*8*8, we studied a gap-free model using molecular dynamics. Physical quantities such as volume and pressure of the Na-O and Li-O systems exhibit similar behaviors around the thermodynamic ensembles NPT and NVE. However, for the Na2O system, at a minimum temperature value, we observe a range of total energy values;in contrast, for the Li2O system, a minimum energy corresponds to a range of temperatures. Finally, for physicochemical properties, we studied the diffusion coefficient and activation energy of lithium and potassium oxides around their melting temperatures. The order of magnitude of the diffusion coefficients is given by the relation Dli-O >DNa-O for the multiplicity 8*8*8, while for the activation energy, the order is well reversed EaNa-O > EaLi-O. 展开更多
关键词 Molecular Dynamics Diffusion Coefficients Activation Energy Lithium Oxide Sodium Oxide Lennard jones Potential Data File Atomic and Charge Models CATHODE LAMMPS
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腱膜性上睑下垂 被引量:7
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作者 林茂昌 《中华医学美学美容杂志》 2008年第2期143-144,共2页
临床实践过程中,许多学者发现在后天性上睑下垂中有一种特殊类型,其发病与上睑提肌腱膜有着直接密切的关系,而且临床表现也大致相似。以往对此类型上睑下垂并没引起广泛重视,也缺乏理论上的认识和指导。1975年Jones等首先提出了腱... 临床实践过程中,许多学者发现在后天性上睑下垂中有一种特殊类型,其发病与上睑提肌腱膜有着直接密切的关系,而且临床表现也大致相似。以往对此类型上睑下垂并没引起广泛重视,也缺乏理论上的认识和指导。1975年Jones等首先提出了腱膜性上睑下垂的概念及相应的手术方法,尔后随着诸多学者的研究和认识的深入,逐渐得到认同和推广,其手术方式和重点已从上睑提肌术式逐步转移到了腱膜术式,为治疗这一类型上睑下垂开创了新的途径,提高了治疗效果。本文将对腱膜性上睑下垂相关问题做一简要介绍。 展开更多
关键词 腱膜性上睑下垂 上睑提肌腱膜 治疗效果 jones 临床实践 临床表现 手术方法 手术方式
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TC治疗在我国戒毒领域的应用现状及前景 被引量:7
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作者 龚国如 邹晓敏 +1 位作者 宋娟 江红 《中国药物依赖性杂志》 CAS CSCD 2006年第1期70-72,共3页
关键词 治疗社区 TC 戒毒 药物成瘾者 jones 治疗模式 社会化 精神病 居住
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盘状半月板的研究进展 被引量:6
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作者 王彬 程飚 《中国临床医学》 2014年第2期234-236,共3页
盘状半月板即盘状软骨,是半月板因异常增大、增厚而形成的近似盘状的结构,盘状半月板多发生于双膝,绝大多数见于外侧半月板。Young在1889年首次报告了外侧盘状半月板,Jones在1930年首次报告了内侧盘状半月板。
关键词 盘状半月板 jones 盘状软骨 外侧
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Inverse-designed Jones matrix metasurfaces for high-performance meta-polarizers
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作者 王志强 李枫竣 +3 位作者 邓倩媚 万舟 李向平 邓子岚 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第2期192-199,共8页
Polarizers have always been an important optical component for optical engineering and have played an indispensable part of polarization imaging systems.Metasurface polarizers provide an excellent platform to achieve ... Polarizers have always been an important optical component for optical engineering and have played an indispensable part of polarization imaging systems.Metasurface polarizers provide an excellent platform to achieve miniaturization,high resolution,and low cost of polarization imaging systems.Here,we proposed freeform metasurface polarizers derived by adjoint-based inverse design of a full-Jones matrix with gradient-descent optimization.We designed multiple freeform polarizers with different filtered states of polarization(SOPs),including circular polarizers,elliptical polarizers,and linear polarizers that could cover the full Poincarésphere.Note that near-unitary polarization dichroism and the ultrahigh polarization extinction ratio(ER)reaching 50 d B were achieved for optimized circular polarizers.The multiple freeform polarizers with filtered polarization state locating at four vertices of an inscribed regular tetrahedron of the Poincarésphere are designed to form a full-Stokes parameters micropolarizer array.Our work provides a novel approach,we believe,for the design of meta-polarizers that may have potential applications in polarization imaging,polarization detection,and communication. 展开更多
关键词 metasurface inverse design jones matrix polarization imaging
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Fifth metatarsal fractures and current treatment 被引量:4
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作者 Julia Bowes Richard Buckley 《World Journal of Orthopedics》 2016年第12期793-800,共8页
Metatarsal fractures are one of the most common injuries of the foot. There has been conflicting literatureon management of fifth metatarsal fractures due to inconsistency with respect to classification of these fract... Metatarsal fractures are one of the most common injuries of the foot. There has been conflicting literatureon management of fifth metatarsal fractures due to inconsistency with respect to classification of these fractures. This article provides a thorough review of fifth metatarsal fractures with examination of relevant literature to describe the management of fifth metatarsal fractures especially the proximal fracture. A description of nonoperative and operative management for fifth metatarsal fractures according to anatomical region is provided. 展开更多
关键词 METATARSAL FRACTURES FIFTH METATARSAL jones fracture OPERATIVE care ATHLETE
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嗜酸性细胞在蠕虫感染免疫中的作用 被引量:5
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作者 马济宏 段利国 《医学动物防制》 2006年第5期327-330,共4页
关键词 嗜酸性细胞增多 感染免疫 蠕虫 jones 寄生虫感染 过敏性疾病 PAUL 酸性染料 亲和力 粗颗粒
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