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Linked color imaging vs Lugol chromoendoscopy for esophageal squamous cell cancer and precancerous lesion screening: A noninferiority study
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作者 Zi-Xin Wang Long-Song Li +15 位作者 Song Su Jin-Ping Li Bo Zhang Nan-Jun Wang Sheng-Zhen Liu Sha-Sha Wang Shuai Zhang Ya-Wei Bi Fei Gao Qun Shao Ning Xu Bo-Zong Shao Yi Yao Fang Liu En-Qiang Linghu Ning-Li Chai 《World Journal of Gastroenterology》 SCIE CAS 2023年第12期1899-1910,共12页
BACKGROUND Lugol chromoendoscopy(LCE)has served as a standard screening technique in high-risk patients with esophageal cancer.Nevertheless,LCE is not suitable for general population screening given its side effects.L... BACKGROUND Lugol chromoendoscopy(LCE)has served as a standard screening technique in high-risk patients with esophageal cancer.Nevertheless,LCE is not suitable for general population screening given its side effects.Linked color imaging(LCI)is a novel image-enhanced endoscopic technique that can distinguish subtle differences in mucosal color.AIM To compare the diagnostic performance of LCI with LCE in detecting esophageal squamous cell cancer and precancerous lesions and to evaluate whether LCE can be replaced by LCI in detecting esophageal neoplastic lesions.METHODS In this prospective study,we enrolled 543 patients who underwent white light imaging(WLI),LCI and LCE successively.We compared the sensitivity and specificity of LCI and LCE in the detection of esophageal neoplastic lesions.Clinicopathological features and color analysis of lesions were assessed.RESULTS In total,43 patients(45 neoplastic lesions)were analyzed.Among them,36 patients(38 neoplastic lesions)were diagnosed with LCI,and 39 patients(41 neoplastic lesions)were diagnosed with LCE.The sensitivity of LCI was similar to that of LCE(83.7%vs 90.7%,P=0.520),whereas the specificity of LCI was greater than that of LCE(92.4%vs 87.0%,P=0.007).The LCI procedure time in the esophageal examination was significantly shorter than that of LCE[42(34,50)s vs 160(130,189)s,P<0.001].The color difference between the lesion and surrounding mucosa in LCI was significantly greater than that observed with WLI.However,the color difference in LCI was similar in different pathological types of esophageal squamous cell cancer.CONCLUSION LCI offers greater specificity than LCE in the detection of esophageal squamous cell cancer and precancerous lesions,and LCI represents a promising screening strategy for general populations. 展开更多
关键词 linked color imaging Lugol chromoendoscopy Esophageal squamous cell cancer Precancerous lesions Color difference
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Clinical usefulness of linked color imaging in identifying Helicobacter pylori infection:A systematic review and meta-analysis
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作者 Yu Zhang Jing-Zhai Wang +2 位作者 Xuan Bai Peng-Li Zhang Qiang Guo 《World Journal of Gastrointestinal Endoscopy》 2023年第12期735-744,共10页
BACKGROUND Accurate diagnosis of Helicobacter pylori(H.pylori)infection status is a crucial premise for eradication therapy,as well as evaluation of risk for gastric cancer.Recent progress on imaging enhancement endos... BACKGROUND Accurate diagnosis of Helicobacter pylori(H.pylori)infection status is a crucial premise for eradication therapy,as well as evaluation of risk for gastric cancer.Recent progress on imaging enhancement endoscopy(IEE)made it possible to not only detect precancerous lesions and early gastrointestinal cancers but also to predict H.pylori infection in real time.As a novel IEE modality,linked color imaging(LCI)has exhibited its value on diagnosis of lesions of gastric mucosa through emphasizing minor differences of color tone.AIM To compare the efficacy of LCI for H.pylori active infection vs conventional white light imaging(WLI).METHODS PubMed,Embase,Embase and Cochrane Library were searched up to the end of April 11,2022.The random-effects model was adopted to calculate the diagnostic efficacy of LCI and WLI.The calculation of sensitivity,specificity,and likelihood ratios were performed;symmetric receiver operator characteristic(SROC)curves and the areas under the SROC curves were computed.Quality of the included studies was chosen to assess using the quality assessment of diagnostic accuracy studies-2 tool.RESULTS Seven original studies were included in this study.The pooled sensitivity,specificity,positive likelihood rate,and negative likelihood rate of LCI for the diagnosis of H.pylori infection of gastric mucosa were 0.85[95%confidence interval(CI):0.76-0.92],0.82(95%CI:0.78-0.85),4.71(95%CI:3.7-5.9),and 0.18(95%CI:0.10-0.31)respectively,with diagnostic odds ratio=26(95%CI:13-52),SROC=0.87(95%CI:0.84-0.90),which showed superiority of diagnostic efficacy compared to WLI.CONCLUSION Our results showed LCI can improve efficacy of diagnosis on H.pylori infection,which represents a useful endoscopic evaluation modality for clinical practice. 展开更多
关键词 Helicobacter pylori infection Endoscopic diagnosis linked color imaging Gastric cancer META-ANALYSIS
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Self-Cross-Linked Tannin-Aminated Tannin Surface Coatings for Particleboard
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作者 Bengang Zhang Antonio Pizzi +2 位作者 Mathieu Petrissans Anelie Petrissans Colin Baptiste 《Journal of Renewable Materials》 EI 2023年第12期4097-4121,共25页
Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)partic... Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)particleboard coating was then prepared by reacting raw tannin extract with aminated tannin extract and thus cross-linking the two by substituting tannin’s hydroxyl groups with the–NH_(2)groups on the aminated tannin to form–NH-bridges between the two.The resulting particleboard coating gave encouraging results when pressed at 180℃for 3 min.Conversely,the system in which tannin was reacted/cross-liked with urea(ATU)by a similar amination reaction did not perform as well as the ATT system,and this even when a higher curing temperature and longer hot press time were used.In particular its water repellence was worse probably due to the presence of urea and such a system with lower reactivity.Nonetheless,substituting the tannin–OHs with the urea–NH_(2)groups appeared to also take place.ATT gave better results than ATU as regards water repellence and mechanical resistance as shown by the cross cut test.The ATT system was shown to be between 95%and 98%biosourced.The difference appeared to be due,by TMA analysis,to the much faster formation of the ATT hardened network leading to a better cross-linked polymer coating.The chemical species formed for both the ATT and ATU system were studied by MALDI ToF and CP MAS^(13)C NMR. 展开更多
关键词 Biocoatings PARTICLEBOARD aminated tannin cross-linked tannin-aminated tannin tannin-urea cross links water repellence cross cut test MALDI ToF ^(13)C NMR
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宫颈病变患者病耻感现状及其相关影响因素分析
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作者 刘淳 段苏纯 +2 位作者 郭建玲 孟繁蒴 曹柳茵 《现代中西医结合杂志》 CAS 2024年第10期1430-1434,共5页
目的 调查宫颈病变患者的病耻感现状,探索其影响因素。方法 采用自行设计一般资料调查问卷和Link病耻感量表(8个维度)对2020年12月—2021年12月在河北医科大学第二医院东院区妇科二科门诊及住院治疗的163例宫颈病变患者进行调查,分析影... 目的 调查宫颈病变患者的病耻感现状,探索其影响因素。方法 采用自行设计一般资料调查问卷和Link病耻感量表(8个维度)对2020年12月—2021年12月在河北医科大学第二医院东院区妇科二科门诊及住院治疗的163例宫颈病变患者进行调查,分析影响宫颈病变患者病耻感的相关因素。结果 回收有效问卷150份,宫颈病变患者的Link病耻感量表总分为(118.82±17.64)分,各维度得分分别为贬低-歧视感知(2.78±0.95)分、挑战(2.94±0.83)分、教育(2.90±0.85)分、分离(2.55±0.73)分、保密(2.41±0.79)分、退缩(2.38±0.69)分、误解(2.83±0.80)分、不同/羞耻(1.99±0.61)分,贬低-歧视感知、挑战、教育、误解维度得分均显著高于量表中点2.5分(P均<0.05),保密、退缩、不同/羞耻维度得分均显著低于量表中点2.5分(P均<0.05)。患者年龄、文化程度、病理活检结果、治疗次数是其病耻感的主要影响因素(P均<0.05)。结论 患者普遍因宫颈病变存在病耻感,且其影响因素较多。患者年龄越小、文化水平越高、病理活检结果级别越高、治疗次数越多,病耻感就越高。 展开更多
关键词 宫颈病变 病耻感 Link病耻感量表 影响因素
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面向Link16的QualNet与虚拟机信息交互接口设计与实现
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作者 杨昊伟 龚鹏 +4 位作者 张继豪 王卫东 唐飞喜 周子骄 张广为 《兵工学报》 EI CAS CSCD 北大核心 2024年第4期1186-1195,共10页
Link16是美国国防部采用的高速视距战术数据链,广泛应用于美国海军、联合部队和北约部队,针对其开展测试评估具有重要军事意义。通过硬件在环技术将Link16实物设备接入到仿真测试中,可有效提高测试结果的真实性和准确性。然而当测试场... Link16是美国国防部采用的高速视距战术数据链,广泛应用于美国海军、联合部队和北约部队,针对其开展测试评估具有重要军事意义。通过硬件在环技术将Link16实物设备接入到仿真测试中,可有效提高测试结果的真实性和准确性。然而当测试场景需要进行实物设备组网测试时,仍会带来成本问题。为此,提出一种面向QualNet MAC层的Link16专属模型以及与之匹配的虚拟机信息交互接口。该模型可高逼真模拟Link16通信行为,实现Link16节点竞争接入、时隙划分、NPG分组等功能。并基于数据分布式服务实现了虚拟机交互接口,将运行在虚拟机的Link16设备模型接入QualNet测试场景。实验测试结果表明,所设计模型具有较高真实性和准确性且接口引入延时不超过1 ms,为大规模数据链网络测试提供一种新方法。 展开更多
关键词 交互接口 LINK16数据链 虚拟机 QualNet MAC层 网络仿真
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On the apparent line-of-sight alignment of the peak X-ray intensity of the magnetosheath and the tangent to the magnetopause,as viewed by SMILE-SXI 被引量:2
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作者 Andrew Read 《Earth and Planetary Physics》 EI CSCD 2024年第1期155-172,共18页
The Soft X-ray Imager(SXI)on board the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)spacecraft will be able to view the Earth’s magnetosheath in soft X-rays.Simulated images of the X-ray emission visible f... The Soft X-ray Imager(SXI)on board the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)spacecraft will be able to view the Earth’s magnetosheath in soft X-rays.Simulated images of the X-ray emission visible from the position of SMILE are created for a range of solar wind densities by using 3 years of the SMILE mission orbit,together with models of the expected X-ray emissivity from the Earth’s magnetosheath.Results from global magnetohydrodynamic simulations and a simple model for exospheric neutral densities are used to compare the locations of the lines of sight along which integrated soft X-ray intensities peak with the lines of sight lying tangent to surfaces(defined here to be the magnetopause)along which local soft X-ray intensities peak or exhibit their strongest gradients,or both,for strongly southward interplanetary magnetic field conditions when no depletion or low-latitude boundary layers are expected.Where,in the parameter space of the various times and seasons,orbital phases,solar wind conditions,and magnetopause models,the alignment of the X-ray emission peak with the magnetopause tangent is good,or is not,is presented.The main results are as follows.The spacecraft needs to be positioned well outside the magnetopause;low-altitude times near perigee are not good.In addition,there are seasonal aspects:dayside-apogee orbits are generally very good because the spacecraft travels out sunward at high altitude,but nightside-apogee orbits,behind the Earth,are bad because the spacecraft only rarely leaves the magnetopause.Dusk-apogee and dawnapogee orbits are intermediate.Dayside-apogee orbits worsen slightly over the first three mission years,whereas nightside-apogee orbits improve slightly.Additionally,many more times of good agreement with the peak-to-tangent hypothesis occur when the solar wind is in a high-density state,as opposed to a low-density state.In a high-density state,the magnetopause is compressed,and the spacecraft is more often a good distance outside the magnetopause. 展开更多
关键词 X-rays MAGNETOSPHERE MAGNETOSHEATH MAGNETOPAUSE Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) Earth solar wind charge exchange
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基于BIM和Linked Data的建筑业电子商务信息融合框架 被引量:4
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作者 李忠富 何丹丹 姜韶华 《工程管理学报》 2017年第5期7-12,共6页
建筑业电子商务平台信息存在海量、异构和分散等问题,影响了建筑业电子商务的发展。在分析现有电子商务平台信息特征,以及研究BIM和Linked Data技术在信息集成方面应用的基础上,提出一种基于BIM和Linked Data的建筑业电子商务信息融合... 建筑业电子商务平台信息存在海量、异构和分散等问题,影响了建筑业电子商务的发展。在分析现有电子商务平台信息特征,以及研究BIM和Linked Data技术在信息集成方面应用的基础上,提出一种基于BIM和Linked Data的建筑业电子商务信息融合框架。该框架以BIM作为商品信息模型;使用Linked Data将供应商信息、客户信息、配送信息、交易信息、采购合同信息关联到商品信息BIM模型中,形成融合的信息环境,为实现建筑业电子商务信息融合提供了一种有效的解决思路。 展开更多
关键词 建筑业电子商务 BIM linked DATA 信息集成
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Using restored two-dimensional X-ray images to reconstruct the three-dimensional magnetopause 被引量:2
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作者 RongCong Wang JiaQi Wang +3 位作者 DaLin Li TianRan Sun XiaoDong Peng YiHong Guo 《Earth and Planetary Physics》 EI CSCD 2024年第1期133-154,共22页
Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosph... Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)aims to capture two-dimensional(2-D)images of the Earth’s magnetosheath by using soft X-ray imaging.However,the observed 2-D images are affected by many noise factors,destroying the contained information,which is not conducive to the subsequent reconstruction of the three-dimensional(3-D)structure of the magnetopause.The analysis of SXI-simulated observation images shows that such damage cannot be evaluated with traditional restoration models.This makes it difficult to establish the mapping relationship between SXIsimulated observation images and target images by using mathematical models.We propose an image restoration algorithm for SXIsimulated observation images that can recover large-scale structure information on the magnetosphere.The idea is to train a patch estimator by selecting noise–clean patch pairs with the same distribution through the Classification–Expectation Maximization algorithm to achieve the restoration estimation of the SXI-simulated observation image,whose mapping relationship with the target image is established by the patch estimator.The Classification–Expectation Maximization algorithm is used to select multiple patch clusters with the same distribution and then train different patch estimators so as to improve the accuracy of the estimator.Experimental results showed that our image restoration algorithm is superior to other classical image restoration algorithms in the SXI-simulated observation image restoration task,according to the peak signal-to-noise ratio and structural similarity.The restoration results of SXI-simulated observation images are used in the tangent fitting approach and the computed tomography approach toward magnetospheric reconstruction techniques,significantly improving the reconstruction results.Hence,the proposed technology may be feasible for processing SXI-simulated observation images. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) soft X-ray imager MAGNETOPAUSE image restoration
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Influencing Factors on Cardiovascular Health in China 被引量:1
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作者 Sheng-Shou HU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第1期4-33,共30页
The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in China.This is the first section of the report,which dissects influential factors across diverse dom... The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in China.This is the first section of the report,which dissects influential factors across diverse domains.The investigation identifies tobacco use as a paramount concern,portraying China as the global epicenter of tobacco consumption.Cigarette smoking,exacerbated by second-hand smoke exposure,emerges as a critical and preventable risk factor,contributing to a surge in attributable deaths over the past three decades.In the realm of dietary nutrition,the study discerns an overall improvement,yet discerns worrisome deviations,notably an escalating fat intake surpassing recommended guidelines.The shifting dietary structure reveals diminished consumption of cereals and vegetables juxtaposed with an uptick in animal foods,while excessive intake of cooking oil and salt persists,straying substantially from endorsed levels.The exploration of physical activity patterns unfolds a nuanced narrative.Varied trends are observed among students,with concerns arising from sedentary behaviors and inadequate adherence to recommended guidelines.The analysis spans a trajectory of declining physical activity in Chinese adults,coupled with an alarming surge in sedentary leisure time,ultimately linking these factors to heightened risks of cardiovascular diseases and increased adiposity.An examination of overweight and obesity trends uncovers a relentless upward trajectory,projecting substantial prevalence by 2030.Noteworthy prevalence rates underscore the imperative for targeted interventions to curtail this burgeoning health crisis,with the anticipated prevalence extending to nearly two-thirds of the adult population.Psychological factors,notably depression,constitute an integral facet of cardiovascular health.Prevalence rates among patients with coronary artery disease and acute myocardial infarction underscore the intricate interplay between mental health and cardiovascular outcomes.Additionally,persistent depressive symptoms are shown to significantly elevate the risk of cardiovascular diseases and mortality.This first section underscores the multifaceted challenges facing cardiovascular health in China,emphasizing the imperative for tailored interventions across tobacco control,dietary habits,physical activity,obesity management,and psychological well-being to mitigate the escalating burden of cardiovascular diseases in the population. 展开更多
关键词 Influencing SMOKE LINKING
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Coherent optical frequency transfer via 972-km fiber link 被引量:1
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作者 邓雪 张翔 +8 位作者 臧琦 焦东东 王丹 刘杰 高静 许冠军 董瑞芳 刘涛 张首刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期277-282,共6页
We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase lockin... We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase locking loop in the conventional active phase control scheme,the passive phase noise cancellation is realized by feeding double-trip beat-note frequency to the driver of the acoustic optical modulator at the local site.This passive scheme exhibits fine robustness and reliability,making it suitable for long-distance and noisy fiber links.An optical regeneration station is used in the link for signal amplification and cascaded transmission.The phase noise cancellation and transfer instability of the 972-km link is investigated,and transfer instability of 1.1×10^(-19)at 10^(4)s is achieved.This work provides a promising method for realizing optical frequency distribution over thousands of kilometers by using fiber links. 展开更多
关键词 optical frequency transfer fiber link phase noise cancellation
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WiFense:从衍射模型到边界监控
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作者 刘兆鹏 李晟洁 +2 位作者 张越 曾有为 张大庆 《软件学报》 EI CSCD 北大核心 2024年第3期1515-1533,共19页
近年来,随着普适计算概念的深入人心,智能感知技术已成为研究者们关注的焦点,且基于WiFi的非接触式感知因其优秀的普适性、低廉的部署成本以及良好的用户体验越来越受到学术界和工业界的青睐.典型的WiFi非接触式感知工作有手势识别、呼... 近年来,随着普适计算概念的深入人心,智能感知技术已成为研究者们关注的焦点,且基于WiFi的非接触式感知因其优秀的普适性、低廉的部署成本以及良好的用户体验越来越受到学术界和工业界的青睐.典型的WiFi非接触式感知工作有手势识别、呼吸检测、入侵检测、行为识别等,这些工作若实际部署,需首先避免其他无关区域中无关行为的干扰,因此需要判断目标是否进入到特定的感知区域中.这意味着系统应具备精准判断目标在界线哪一侧的能力,然而现有工作未能找到一个可以对某个自由设定的边界进行精确监控的方法,这阻碍了WiFi感知应用的实际落地.基于这一关键问题,从电磁波衍射的物理本质出发,结合菲涅尔衍射模型(Fresnel diffraction model),找到一种目标穿越link(收发设备天线的连线)时的信号特征(Rayleigh distribution in Fresnel diffraction model,RFD),并揭示该信号特征与人体活动之间的数学关系;之后以link作为边界,结合天线间距带来的波形时延以及AGC(automatic gain control)在link被遮挡时的特征,通过越线检测实现对边界的监控.在此基础上,还实现了两个实际应用,即入侵检测系统和居家状态监测系统,前者的精确率超过89%、召回率超过91%,后者的准确率超过89%.在验证所提边界监控算法的可用性和鲁棒性的同时,也展示了所提方法与其他WiFi感知技术相结合的巨大潜力,为WiFi感知技术的实际部署提供了思考方向. 展开更多
关键词 非接触式感知 WIFI 信道状态信息(CSI) link穿越检测 边界监控
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Corneal collagen cross-linking in patients with keratoconus from the Dresden protocol to customized solutions:theoretical basis 被引量:1
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作者 Ciro Caruso Luca D’Andrea +4 位作者 Mario Troisi Michele Rinaldi Raffaele Piscopo Salvatore Troisi Ciro Costagliola 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期951-962,共12页
Keratoconus is an ectatic condition characterized by gradual corneal thinning,corneal protrusion,progressive irregular astigmatism,corneal fibrosis,and visual impairment.The therapeutic options regarding improvement o... Keratoconus is an ectatic condition characterized by gradual corneal thinning,corneal protrusion,progressive irregular astigmatism,corneal fibrosis,and visual impairment.The therapeutic options regarding improvement of visual function include glasses or soft contact lenses correction for initial stages,gas-permeable rigid contact lenses,scleral lenses,implantation of intrastromal corneal ring or corneal transplants for most advanced stages.In keratoconus cases showing disease progression corneal collagen crosslinking(CXL)has been proven to be an effective,minimally invasive and safe procedure.CXL consists of a photochemical reaction of corneal collagen by riboflavin stimulation with ultraviolet A radiation,resulting in stromal crosslinks formation.The aim of this review is to carry out an examination of CXL methods based on theoretical basis and mathematical models,from the original Dresden protocol to the most recent developments in the technique,reporting the changes proposed in the last 15y and examining the advantages and disadvantages of the various treatment protocols.Finally,the limits of non-standardized methods and the perspectives offered by a customization of the treatment are highlighted. 展开更多
关键词 corneal collagen cross linking KERATOCONUS custom fast protocol Dresden protocol lambert-beer law Bunsen-roscoe law
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Analysis of the joint detection capability of the SMILE satellite and EISCAT-3D radar 被引量:2
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作者 JiaoJiao Zhang TianRan Sun +7 位作者 XiZheng Yu DaLin Li Hang Li JiaQi Guo ZongHua Ding Tao Chen Jian Wu Chi Wang 《Earth and Planetary Physics》 EI CSCD 2024年第1期299-306,共8页
The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology... The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology to perform large-scale imaging of the Earth’s magnetosheath and polar cusp regions.It uses a high-precision ultraviolet imager to image the overall configuration of the aurora and monitor changes in the source of solar wind in real time,using in situ detection instruments to improve human understanding of the relationship between solar activity and changes in the Earth’s magnetic field.The SMILE satellite is scheduled to launch in 2025.The European Incoherent Scatter Sciences Association(EISCAT)-3D radar is a new generation of European incoherent scatter radar constructed by EISCAT and is the most advanced ground-based ionospheric experimental device in the high-latitude polar region.It has multibeam and multidirectional quasi-real-time three-dimensional(3D)imaging capabilities,continuous monitoring and operation capabilities,and multiple-baseline interferometry capabilities.Joint detection by the SMILE satellite and the EISCAT-3D radar is of great significance for revealing the coupling process of the solar wind–magnetosphere–ionosphere.Therefore,we performed an analysis of the joint detection capability of the SMILE satellite and EISCAT-3D,analyzed the period during which the two can perform joint detection,and defined the key scientific problems that can be solved by joint detection.In addition,we developed Web-based software to search for and visualize the joint detection period of the SMILE satellite and EISCAT-3D radar,which lays the foundation for subsequent joint detection experiments and scientific research. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite European Incoherent Scatter Sciences Association(EISCAT)-3D radar joint detection
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一种改进的Link16信号检测方法
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作者 薛燕 高春芳 杨欣 《现代雷达》 CSCD 北大核心 2024年第1期39-44,共6页
直接序列扩频、高速跳频与跳时相结合的技术,造成了对Link16信号的检测具有相当的难度。文中针对突发Link16信号脉冲宽度强规律性,借鉴双滑动窗算法在突发信号检测上的应用,提出了改进后基于相关处理的双滑动窗Link16信号检测方法,该方... 直接序列扩频、高速跳频与跳时相结合的技术,造成了对Link16信号的检测具有相当的难度。文中针对突发Link16信号脉冲宽度强规律性,借鉴双滑动窗算法在突发信号检测上的应用,提出了改进后基于相关处理的双滑动窗Link16信号检测方法,该方法可实现复杂电磁环境下对Link16信号的高灵敏度、高概率检测,同时正确估算出脉宽、码速率等参数信息。仿真实验数据验证了理论分析的正确性和所述方法的有效性,相较于其他Link16信号检测方法,改进后的基于相关处理的双滑动窗检测算法明显提高了在低信噪比下对Link16信号的检测能力。 展开更多
关键词 Link16信号 双窗滑动相关 突发信号检测
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Simulation of the SMILE Soft X-ray Imager response to a southward interplanetary magnetic field turning 被引量:1
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作者 Andrey Samsonov Graziella Branduardi-Raymont +3 位作者 Steven Sembay Andrew Read David Sibeck Lutz Rastaetter 《Earth and Planetary Physics》 EI CSCD 2024年第1期39-46,共8页
The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)Soft X-ray Imager(SXI)will shine a spotlight on magnetopause dynamics during magnetic reconnection.We simulate an event with a southward interplanetary magne... The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)Soft X-ray Imager(SXI)will shine a spotlight on magnetopause dynamics during magnetic reconnection.We simulate an event with a southward interplanetary magnetic field turning and produce SXI count maps with a 5-minute integration time.By making assumptions about the magnetopause shape,we find the magnetopause standoff distance from the count maps and compare it with the one obtained directly from the magnetohydrodynamic(MHD)simulation.The root mean square deviations between the reconstructed and MHD standoff distances do not exceed 0.2 RE(Earth radius)and the maximal difference equals 0.24 RE during the 25-minute interval around the southward turning. 展开更多
关键词 MAGNETOPAUSE magnetic reconnection solar wind charge exchange southward interplanetary magnetic field numerical modeling Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) Soft X-ray Imager
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基于电机数据图像化的多时序变量间接卡车误吊起检测
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作者 刘嘉杰 刘国平 胡文山 《计算机工程》 CAS CSCD 北大核心 2024年第10期370-380,共11页
自动化集装箱码头的装卸作业中经常发生集装箱与卡车同时被吊起的安全事故,导致人员伤亡及货品、车辆的损坏。为解决该问题,提出一种基于电机数据图像化处理的多时序变量间接卡车误吊起检测方法(MEIN)。该方法通过神经网络分析异步电机... 自动化集装箱码头的装卸作业中经常发生集装箱与卡车同时被吊起的安全事故,导致人员伤亡及货品、车辆的损坏。为解决该问题,提出一种基于电机数据图像化处理的多时序变量间接卡车误吊起检测方法(MEIN)。该方法通过神经网络分析异步电机在吊起集装箱和卡车的过程中产生的电流和电压异常,从而判断是否发生了误吊起事故。采集吊机的三相电流和电压数据,并基于物理公式进行特征工程计算出多个相关时序物理量,采用滑动窗口、SMOTE-Tomek综合采样的方式扩大样本总数并平衡类别数量,最后将多时序变量转换为图像的形式以EfficientNet进行分类。实验结果表明,该方法能在复杂的环境下(例如雨雾天气或轮胎被遮挡)保持稳定的检测性能,各测试地区的AUC均在0.997以上。相较于传统的基于激光雷达和计算机视觉的检测方法,MEIN方法具有成本低、精度高、计算量小并且抗环境干扰能力强等优点。该方法已在武汉、青岛、钦州、梅山等多地部署,为提高自动化集装箱码头的作业安全提供一种有效的解决方案。 展开更多
关键词 时间序列分类 卷积神经网络 合成少数类样本的过采样技术 Tomek Links欠采样技术 卡车误吊起检测
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Biodiversity metrics on ecological networks: Demonstrated with animal gastrointestinal microbiomes 被引量:1
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作者 Zhanshan(Sam)Ma Lianwei Li 《Zoological Research(Diversity and Conservation)》 2024年第1期51-65,共15页
Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity... Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity should be similar with measuring national wealth.Indeed,there have been many parallels between ecology and economics,actually beyond analogies.For example,arguably the second most widely used biodiversity metric,Simpson(1949)’s diversity index,is a function of familiar Gini-index in economics.One of the biggest challenges has been the high“diversity”of diversity indexes due to their excessive“speciation”-there are so many indexes,similar to each country’s sovereign currency-leaving confused diversity practitioners in dilemma.In 1973,Hill introduced the concept of“numbers equivalent”,which is based on Renyi entropy and originated in economics,but possibly due to his abstruse interpretation of the concept,his message was not widely received by ecologists until nearly four decades later.What Hill suggested was similar to link the US dollar to gold at the rate of$35 per ounce under the Bretton Woods system.The Hill numbers now are considered most appropriate biodiversity metrics system,unifying Shannon,Simpson and other diversity indexes.Here,we approach to another paradigmatic shift-measuring biodiversity on ecological networks-demonstrated with animal gastrointestinal microbiomes representing four major invertebrate classes and all six vertebrate classes.The network diversity can reveal the diversity of species interactions,which is a necessary step for understanding the spatial and temporal structures and dynamics of biodiversity across environmental gradients. 展开更多
关键词 Biodiversity on network Hill numbers Animal gut microbiome Network link diversity Network species diversity Network abundance-weighted link diversity
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Concerns arise: wheat allergy risk in pre-packaged food products from China
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作者 Wenfeng Liu Jian Wang +5 位作者 Zhongliang Wang Fangfang Min Yong Wu Juanli Yuan Jinyan Gao Hongbing Chen 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3139-3149,共11页
Understanding and monitoring the cross-contamination of food allergens is crucial for safeguarding public health and ensuring food safety.Food allergen risk assessment,derived from classical toxicological principles,c... Understanding and monitoring the cross-contamination of food allergens is crucial for safeguarding public health and ensuring food safety.Food allergen risk assessment,derived from classical toxicological principles,can identify and quantify the risk of allergies.This study aimed to investigate the risk of wheat allergic reactions to prepackaged foods from China through the utilization of food allergen risk assessment.A total of 575 products have been surveyed,wheat/gluten,milk and egg were major allergens labelled on products.According to voluntary incidental trace allergen labelling 3.0(VITAL®3.0)program,the number of products belonged to Action Level 2 were 303.Integration of precautionary allergen labeling(PAL)analysis indicated that 9.57%products would pose a potential risk to wheat allergic individuals.The probabilistic risk assessment results suggest that 7984 allergic reactions may arise among wheat-allergic consumers during 10000 eating occasions due to the consumption of pre-packaged food products with incorrect wheat-related allergen labelling.This study demonstrated that a risk assessment-based approach can support the guidance of allergen labelling and management of food allergen for pre-packaged food products,providing protection for allergic individuals in food consumption and for food manufacturers in food production and trade. 展开更多
关键词 Food allergens Allergen labelling Pre-packaged food Enzyme linked immunosorbent assay(ELISA) Voluntary incidental trace allergen labelling (VITAL) Quantitative risk assessment
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From London buses to activity trackers:A reflection of 70 years of physical activity research
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作者 Ding Ding Ulf Ekelund 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期736-738,共3页
In 1953,Morris et al.^(1)published their ground-breaking findings among London bus drivers and conductors,linking physical activity to a major chronic disease for the first time.This seminal paper marked the birth of ... In 1953,Morris et al.^(1)published their ground-breaking findings among London bus drivers and conductors,linking physical activity to a major chronic disease for the first time.This seminal paper marked the birth of a new field—physical activity epidemiology.^(1)Since then,the field has flourished,evidenced by mounting scientific publications.^(2)Our knowledge about the role of physical activity in disease prevention has expanded from coronary heart disease in Morris et al.’s^(1)initial study to dozens of additional diseases and conditions,such as diabetes,cancers,and dementia.^(3)More than 7 decades and thousands of publications later,we critically reflect on several aspects of the progress in physical activity epidemiology. 展开更多
关键词 EPIDEMIOLOGY PREVENTION LINKING
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A tensile wearable SHF antenna with efficient communication in defense beacon technology
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作者 Pooja Naresh Bhatt Rashmi Pandhare 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期198-210,共13页
The study projects a flexible and compact wearable pear-shaped Super High Frequency(SHF)antenna that can provide detailed location recognition and tracking applicable to defense beacon technology.This mini aperture wi... The study projects a flexible and compact wearable pear-shaped Super High Frequency(SHF)antenna that can provide detailed location recognition and tracking applicable to defense beacon technology.This mini aperture with electrical dimensions of 0.12λ_(0)×0.22λ_(0)×0.01λ_(0)attains a vast bandwidth over 3.1-34.5 GHz Super High Frequency(SHF)frequency band at S_(11)≤-10 dB,peak gain of 7.14 dBi and proportionately homogeneous radiation pattern.The fractional bandwidth(%BW)acquired is 168%that envelopes diversified frequency spectrum inclusive of X band specifically targeted to all kinds of defense and military operations.The proposed antenna can be worn on a soldier's uniform and hence the Specific Absorption Rate simulation is accomplished.The Peak SAR Value over 1 g of tissue is 1.48 W/kg and for 10 g of tissue is 0.27 W/kg well under the safety standards.The flexibility is proven by analyzing the full electromagnetic simulations for various bending conditions.Time response analysis is attained with its Fidelity Factor and Group Delay.Communication excellence is determined using Link Budget Analysis and it is seen that margin at 100 Mbps is 62 m and at 200 Mbps is 59 m.Prototype is fabricated along with experimental validation.All the results show harmony in shaping the antenna to provide critical situational awareness and data sharing capabilities required in defense beacon technology for location identification. 展开更多
关键词 COMPACT Defense beacon technology Link budget SAR Time domain WEARABLE
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