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A Qualitative Study on Diagnosing Myopia Using the Ratio of Axial Length to Corneal Radius of Curvature
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作者 Lijuan Zeng Ming Yang 《Journal of Clinical and Nursing Research》 2025年第11期87-95,共9页
Objective:To investigate the influence of axial length(AL),corneal curvature(CR),and the ratio of axial length to corneal radius of curvature(AL/CR)on myopia in children,and to evaluate the accuracy and specificity of... Objective:To investigate the influence of axial length(AL),corneal curvature(CR),and the ratio of axial length to corneal radius of curvature(AL/CR)on myopia in children,and to evaluate the accuracy and specificity of AL/CR in diagnosing myopia in children.Methods:A cross-sectional study was conducted.A total of 200 children(400 eyes)aged 6-12 years were recruited from the ophthalmology outpatient clinic of Fuling District People’s Hospital from December 2022 to December 2023.AL,CR,and AL/CR were measured,and comprehensive optometry was performed under cycloplegia,with the results recorded in spherical equivalent(SE)form.Results:A total of 200 subjects(400 eyes)were included in this study,of which 330 eyes(82.50%)were myopic.No significant differences in CR were observed among different refractive groups,while significant differences were noted in SE,AL,and AL/CR.The AL and AL/CR ratios were higher in myopic eyes compared to emmetropic and hyperopic eyes.Using cycloplegia as the gold standard,SE in the myopia group was correlated with AL,AL/CR,and CR,with stronger correlations observed with AL and AL/CR.An AL/CR value>3 demonstrated a sensitivity of 0.918,specificity of 0.786,misdiagnosis rate of 0.214,missed diagnosis rate of 0.082,and accuracy of 89.5%in diagnosing myopia.Conclusion:AL and AL/CR values are highly correlated with SE,with the strongest correlation observed in the myopia group.The AL/CR value exhibits high diagnostic value in determining myopia in children. 展开更多
关键词 Axial length Corneal radius of curvature Ratio of axial length to corneal radius of curvature MYOPIA CHILDREN
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Role of post-operative X-rays in distal-radius fractures among pediatric patients 被引量:1
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作者 Ammar K Alomran Bandar A Alzahrani +4 位作者 Dana S Alamoud Layan S Alsultan Meshail M AlSaud Raneem G Althobaiti Badriah S Alruwaili 《World Journal of Orthopedics》 2025年第5期51-60,共10页
BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appea... BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appears to provide limited additional benefit.AIM To determine the necessary number of follow-up X-rays to use resources efficiently.METHODS Participants included in this study are pediatric age group patients who were treated operatively for distal radius/both bone fractures and were identified from a prospected collected data from the operating room database between the years 2009 and 2017.The data in the study included patients who had distal radius fractures and underwent fixation surgery(n=88).RESULTS When assessing the difference in the odds of conducting 1 or less X-ray compared to 2 or more X-rays in regard to the type of fixation,the only significant difference is the closed reduction fixation method.Patients who underwent closed reduction method procedure have significantly lower odds of having 2 more X-rays compared to those who didn’t have closed reduction method.Open reduction,internal fixation,and other fixation methods(close reduction and internal fixation,debridement,or epiphysiodesis)have higher odds of having two or more X-rays compared to patients who did not receive these methods;however,these odds are not statistically significant.CONCLUSION The findings of this study reveal notable absence of a statistically significant association between the frequency of postoperative X-rays and the outcome of children with distal radius fractures. 展开更多
关键词 X-RAY Distal radius fractures PEDIATRICS ORTHOPEDIC FRACTURES
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THE SPECTRAL RADIUS OF UNIFORM HYPERGRAPH DETERMINED BY THE SIGNLESS LAPLACIAN MATRIX
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作者 HE Fang-guo 《数学杂志》 2025年第1期1-12,共12页
This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh ... This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh principle and the perturbation of the spectral radius under moving the edge operation,and the extremal hypergraphs are characterized for both supertree and unicyclic hypergraphs.The spectral radius of the graph is generalized. 展开更多
关键词 spectral radius uniform hypergraph Signless Laplasian matrix
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The A_(α)-spectral Radius of Block Graphs with Given Dissociation Number
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作者 HUANG Peng LI Jianxi 《数学进展》 北大核心 2025年第4期696-708,共13页
For a simple graph G,let A(G)and D(G)be the adjacency matrix and the diagonal degree matrix of G,respectively.[Appl.Anal.Discrete Math.,2017,11(1):81-107]defined the matrix A_(α)(G)of G as A_(α)(G)=αD(G)(1-α)A(G)... For a simple graph G,let A(G)and D(G)be the adjacency matrix and the diagonal degree matrix of G,respectively.[Appl.Anal.Discrete Math.,2017,11(1):81-107]defined the matrix A_(α)(G)of G as A_(α)(G)=αD(G)(1-α)A(G),α∈[0,1].The Aa-spectral radius is the largest eigenvalue of A_(α)(G).Let G_(n,β) be the set graphs with order n and dissociation numberβ.In this paper,we identify the b with maximal A_(α)-spectral radius among all graphs in G_(n,β). 展开更多
关键词 A_(α)-spectral radius block graph SIZE dissociation number
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The Minimum Spectral Radius of Graphs with Given Pendant Vertices
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作者 LI Hao LIU Chang LI Jianping 《数学进展》 北大核心 2025年第5期973-982,共10页
For a graph G,a vertex is said to be pendant if its neighborhood contains exactly one vertex.In this paper,we determine the extremal graphs among all n-vertex graphs with the minimum spectral radius andβpendant verti... For a graph G,a vertex is said to be pendant if its neighborhood contains exactly one vertex.In this paper,we determine the extremal graphs among all n-vertex graphs with the minimum spectral radius andβpendant vertices,whereβe{1,2,3,4,n-3,n-2,n-1}. 展开更多
关键词 minimum spectral radius pendant vertex extremal graph
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RADIUS在远程接入安全认证中的应用 被引量:8
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作者 曹敬 张敬平 《计算机工程与应用》 CSCD 北大核心 2003年第7期134-136,共3页
该文深入分析了在Linux平台下用FreeRadius软件构建远程用户安全认证服务器的原理和RADIUSClient/Server集成配置的实现方法。这种实现方法在笔者承担的基金项目中得到充分的应用,实践证明该方法安全、高效、可行。
关键词 radius 安全认证 Freeradius软件 网络接人服务器 计算机网络
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Post-operative imaging in pediatric distal radius fractures:When tradition meets evidence
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作者 Amr Elshahhat 《World Journal of Orthopedics》 2025年第8期6-13,共8页
Routine postoperative radiographs after surgical fixation of pediatric distal-radius fractures have long been part of standard care.Yet growing evidence shows that these images rarely change management in stable cases... Routine postoperative radiographs after surgical fixation of pediatric distal-radius fractures have long been part of standard care.Yet growing evidence shows that these images rarely change management in stable cases,adding unnecessary cost,radiation exposure,and clinical burden.A recent study highlights this issue and questions whether routine imaging truly benefits patient outcomes.As orthopedic care shifts toward more patient-centered and value-driven models,there is increasing support for the judicious use of radiographs,reserving imaging for cases where clinical examination or patient symptoms suggest a potential problem.This shift would reflect a broader movement within orthopedic practice:Aligning tradition with necessity,and optimizing care based on evidence rather than habit. 展开更多
关键词 Pediatric distal radius fracture Loss of reduction Follow-up radiographs Cast immobilization K-wire fixation Re-displacement
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Osteosynthesis of the Displaced Fractures of the Distal Radius Treated with New-Clip® Plate: Case Study in the Basse Terre Hospital
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作者 Johnny Cizemba Hugues Albini Christian Dumontier 《Open Journal of Orthopedics》 2025年第2期88-101,共14页
Background and Objectives: The distal radius fracture (DRF) is a major public health problem in northern countries. Its frequency is constantly increasing. The locked anterior plate with its well-established biomechan... Background and Objectives: The distal radius fracture (DRF) is a major public health problem in northern countries. Its frequency is constantly increasing. The locked anterior plate with its well-established biomechanical properties, offers a reliable alternative. The aim of this study was to evaluate the radiological, the functional results and to determine the factors of poor postoperative prognosis of DRF treated with Newclip radial plates®. Methodology: This prospective cohort study evaluates the radiological and functional outcames of displaced radius fractures (DRFs) in patients ≥50 years old treated with Newclip® (locked anterior plates) at the Basse-Terre Hospital in Guadeloupe from 2022 to 2024. The patients were categorized into those with epiphyseal involvement (E1 - E4) and without epiphyseal involvement (E0) based on Laulan’s MEU classification. Radiological parameters (distal radio-ulnar index (DRUI), radial inclination frant view (IRF), radial inclination sagittal view (IRS) were assessed pre and post-operatively. Functional recovery was evaluated at 12 months using the QuickDash questionnaire. Results: Falls were the most common cause of fracture. Post-operatively, SRI was the least restored parameter. Poor prognostic factor for SRI improvement included posterior commimution and unstable fractures. Factors associated with higher QuickDash scores included unstable factures, unrestored DRUI, low plate position, metaphyseal features, and ulnar features. Conclusion: The anterior locking plate osteosynthesis is reliable treatment option with excellent functional outcomes. 展开更多
关键词 Fracture Distal radius Surgical Treatment Newclip® Plate Basse Terre
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Minimally invasive plate osteosynthesis for distal radius fractures using a 3-point positioning technique
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作者 You-You Ye Zhao-Qing Shen +1 位作者 Chun-Ling Wu Yan-Bin Lin 《World Journal of Orthopedics》 2025年第7期92-100,共9页
BACKGROUND The volar approach with plate fixation is the gold standard for treating distal radius fractures,often requiring incision of the pronator quadratus(PQ)muscle.Preserving the PQ during surgery may facilitate ... BACKGROUND The volar approach with plate fixation is the gold standard for treating distal radius fractures,often requiring incision of the pronator quadratus(PQ)muscle.Preserving the PQ during surgery may facilitate early postoperative recovery.However,conventional minimally invasive plate osteosynthesis(MIPO)techniques frequently necessitate multiple(3-4)intraoperative fluoroscopic adjustments to achieve optimal plate positioning,which can inadvertently damage the PQ muscle.Based on our clinical observations,we developed a novel 3-point positioning technique to minimize PQ injury while ensuring accurate plate placement.Preliminary results demonstrate promising early clinical outcomes.AIM To retrospectively analyze distal radius fractures treated using the 3-point positioning-assisted MIPO technique with preservation of the PQ.METHODS The 3-point positioning technique was applied:The Kirschner wire was inserted after fluoroscopy and was correctly adjusted the position of the plate above the PQ.With the aid of Kirschner wires positioning the PQ stripping was performed only once,and the plate then placed in a correct and satisfactory position.Operation time,incision length,wrist pain score,upper extremity function disabilities of the arm,shoulder and hand(DASH)score,wrist Gartland-Werley score,wrist grip strength,and range of motion were among the quantitative variables recorded.Qualitative variables including AO fracture classification,intraoperative and postoperative complications were evaluated.RESULTS At a mean follow-up of 6.9±0.8 months,the mean scar length was 25.4±1.5 mm,the pain score was 0.7±0.6,the DASH score for the upper limb was 4.7±1.3,and the Gartland-Werley score for wrist function was 4.1±1.1 at the last follow-up.Mean flexion was 97.3%,extension was 97.0%,pronation was 98.9%,supination was 98.9%,and grip strength was 86.6%compared to contralateral values.No unfavorable intraoperative or postoperative complications occurred.CONCLUSION The 3-point positioning technique may reduce the damage to the PQ muscle and is a safe and effective method for MIPO for distal radius fractures. 展开更多
关键词 Distal radius fractures Minimally invasive plate osteosynthesis Pronator quadratus sparing technique 3-point positioning technology
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The A_(α)-Spectral Radius and k-Extendability in Graphs
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作者 HA Jing WEN Fei 《Wuhan University Journal of Natural Sciences》 2025年第2期118-124,共7页
A graph is called k-extendable if each k-matching can be extended to a perfect matching.In this paper,we provide a sufficient condition in terms of the Aa-spectral radius for the k-extendability of a connected graph a... A graph is called k-extendable if each k-matching can be extended to a perfect matching.In this paper,we provide a sufficient condition in terms of the Aa-spectral radius for the k-extendability of a connected graph and characterize the corresponding extremal graphs.In addition,such an A_(α)-spectral condition of a connected balanced bipartite graph is also considered,and the corresponding extremal graphs are determined. 展开更多
关键词 A_(α)-spectral radius MATCHING k-extendable graph
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Linux环境下对VPN用户认证的Radius服务器的设计与实现 被引量:4
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作者 黄继征 《现代图书情报技术》 CSSCI 北大核心 2005年第7期22-24,10,共4页
文章介绍了Radius协议的原理,并详细描述了用FreeRadius软件构建Radius服务器对VPN用户进入认证的具体实现方法。
关键词 虚拟专用网 VPN 认证 radius FREEradius
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RADIUS服务器性能测试软件的设计与实现 被引量:2
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作者 孟小华 《微型机与应用》 2004年第6期12-14,17,共4页
RADIUS服务器的性能指标及其测试方法,给出了一个RADIUS服务器性能测试软件的设计思想和具体实现技术。
关键词 radius协议 AAA服务器 radius服务器 性能指标 测试方法 通信网络
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New text classification algorithm based on interdependence and equivalent radius
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作者 王洪伟 伊磊 王建会 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期63-69,共7页
To improve the traditional classifying methods, such as vector space model (VSM)-based methods with highly complicated computation and poor scalability, a new classifying method ( called IER) is presented based on... To improve the traditional classifying methods, such as vector space model (VSM)-based methods with highly complicated computation and poor scalability, a new classifying method ( called IER) is presented based on two new concepts: interdependence and equivalent radius. In IER, the attribute is selected according to the value of interdependence, and the classifying rule is based on equivalent radius and center of gravity. The algorithm analysis shows that IER is good at classifying a large number of samples with higher scalability and lower computation complexity. After several experiments in classifying Chinese texts, the conclusion is drawn that IER outperforms k-nearest neighbor (kNN) and classifcation based on the center of classes (CCC) methods, so IER can be used online to automatically classify a large number of samples while keeping higher precision and recall. 展开更多
关键词 CLASSIFICATION equivalent radius vector space INTERDEPENDENCE interdependence and equivalent radius
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Generalized Numerical Radius of Real Quaternion Matrices with Symmetric Function
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作者 夏铁成 张鸿庆 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期34-38,共5页
In the paper the generalized numerical radiuses of real quaternion matrices with symmetric function are defined and theirs inequalities are given.
关键词 numerical radius generalized numerical radius symmetric function
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应用TekRADIUS零成本构建网络设备统一认证系统 被引量:2
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作者 巫俊峰 《电信技术》 2012年第8期25-29,共5页
从宽带运营商IP城域网接入层设备的运维现状出发,对统一认证系统进行需求分析,利用TekRADIUS免费软件构建出基于RADIUS协议的AAA认证服务器,实现了对思科、华为、H3C等厂商的网络设备进行集中认证和权限分级管理。
关键词 Tekradius 统一认证 AAA认证 radius扩展属性
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在Linux下的Radius服务器的组建及维护
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作者 林建树 《中国电子商务》 2012年第10期57-57,共1页
在我国互联网飞速发展的今天,我们的网民数持续增长,根据中国互联网信息统计中心统计,至2011年11月,我国的网民总数约为5.05亿,手机网民数达3.4亿。因此对互联网接入服务有着巨大需求,目前在全世界范围,提供互联网接入服务的... 在我国互联网飞速发展的今天,我们的网民数持续增长,根据中国互联网信息统计中心统计,至2011年11月,我国的网民总数约为5.05亿,手机网民数达3.4亿。因此对互联网接入服务有着巨大需求,目前在全世界范围,提供互联网接入服务的运营商大部分都使用免费开源的FreeRadius做二次开发并使用。因此学习FreeRadius在Linux系统上的组建和维护显得十分有用。 展开更多
关键词 FREEradius radius服务器组建 radius服务器维护 AAA服务器
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RADIUS在802.1x中的应用 被引量:18
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作者 黄永锋 王滨 许晓东 《计算机工程与设计》 CSCD 北大核心 2006年第5期798-801,共4页
在802.1x中使用RADIUS认证,可以为宽带网络提供一种安全的认证、授权、计费方案,而用户的统一认证、上网时限控制和同一账户的多人使用问题并没有被RADIUS本身所解决,使用目录树统一存储用户信息,并通过Schema扩展RadiusSi-multaneous和... 在802.1x中使用RADIUS认证,可以为宽带网络提供一种安全的认证、授权、计费方案,而用户的统一认证、上网时限控制和同一账户的多人使用问题并没有被RADIUS本身所解决,使用目录树统一存储用户信息,并通过Schema扩展RadiusSi-multaneous和RadiusLoginTime属性以及改进认证流程可以解决上述问题。 展开更多
关键词 802.1x NAS radius EAP 轻量级目录访问协议 单点登录
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RADIUS服务器安全性分析及其改进 被引量:8
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作者 张琪 喻占武 李锐 《计算机工程》 CAS CSCD 北大核心 2007年第5期146-148,共3页
对RADIUS协议所采用的通过共享密钥、认证码等实现的安全措施进行分析,指出其仍然存在的多方面的安全漏洞。在实现中针对RADIUS协议的安全漏洞采取可能的改进措施,在一定程度上弥补了RADIUS协议安全性上的不足,使实现的RADIUS服务器端... 对RADIUS协议所采用的通过共享密钥、认证码等实现的安全措施进行分析,指出其仍然存在的多方面的安全漏洞。在实现中针对RADIUS协议的安全漏洞采取可能的改进措施,在一定程度上弥补了RADIUS协议安全性上的不足,使实现的RADIUS服务器端更好地满足了实际应用的需要。 展开更多
关键词 radius 共享密钥 认证码 安全性
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一种基于Linux的Radius客户端的设计与实现 被引量:6
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作者 赵宇 刘刚 杨宗凯 《计算机工程》 CAS CSCD 北大核心 2003年第15期112-114,共3页
提出了一种基于Linux操作系统的Radius客户端的设计,具有良好的可扩展性并通过并行处理解决了现有的客户端数目增加导致阻塞的问题。基于Red Hat Linux6.2系统加以实现并通过测试达到了良好的效果。
关键词 radius 验证 授权 计费 网络接入服务器
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802.1x标准和Radius协议的扩展应用研究 被引量:15
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作者 蒋海锋 苗放 《计算机应用》 CSCD 北大核心 2003年第11期88-90,共3页
首先介绍了802.1x标准和RADIUS协议的基本概念和原理,并对802.1x标准和RADIUS协议在宽带网络和无线网络中的应用做了分析,结合实际应用的需求,指出了802.1x标准和RADIUS协议在实际应用中的不足与缺陷,分析其难以推广的原因,提出了实现... 首先介绍了802.1x标准和RADIUS协议的基本概念和原理,并对802.1x标准和RADIUS协议在宽带网络和无线网络中的应用做了分析,结合实际应用的需求,指出了802.1x标准和RADIUS协议在实际应用中的不足与缺陷,分析其难以推广的原因,提出了实现扩展应用的设计方案和具体实现方法,以符合宽带环境下认证和计费的实际应用需求。 展开更多
关键词 802.1x radius 认证 计费 宽带网络
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