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青少年及成人水痘的流行情况与免疫策略进展

中华预防医学杂志 2025年第1期59卷 116-122页

作者：戚小华郑舒涵苏颖罗锋何寒青浙江省疾病预防控制中心免疫规划所杭州310051 杭州医学院公共卫生学院杭州310053 浙江中医药大学公共卫生学院杭州310053

水痘是由水痘-带状疱疹病毒原发感染引起的一种常见急性传染病,以全身症状和皮肤黏膜出现斑疹、丘疹、疱疹为特征。水痘多见于儿童,但青少年及成年人感染后病情相对较重。随着以疫苗接种为基础的防控措施实施,我国水痘的发病年龄出现向... 详细信息

水痘是由水痘-带状疱疹病毒原发感染引起的一种常见急性传染病,以全身症状和皮肤黏膜出现斑疹、丘疹、疱疹为特征。水痘多见于儿童,但青少年及成年人感染后病情相对较重。随着以疫苗接种为基础的防控措施实施,我国水痘的发病年龄出现向高年龄组转移的现象,导致青少年及成人水痘病例增加。本文对国内外青少年和成人水痘的临床症状、流行病学特征以及免疫策略的研究进展进行综述,旨在深化对青少年和成人水痘防控的认识,为该人群免疫与防控策略制定提供参考,进一步促进水痘疫苗在全生命周期健康管理的重要作用。

关键词：水痘青少年成年人流行特征免疫策略

Spatial Raman mapping investigation of SERS performance related to localized surface plasmons

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Nano Research 2020年第1期13卷 138-144页

作者： Yansheng Liu feng luo IMDEA Nanoscience Faraday 9Ciudad Universitaria de Cantoblanco28049MadridSpain School of Science Universidad Autónoma de MadridCiudad Universitaria de Cantoblanco28049MadridSpain

In this research,it reported a novel three-dimensional(3D)metallic hybrid system by introducing single-layer graphene(SLG)between silver nanoparticles(NPs)and silver nano-discs(NDs)arrays(Ag NPs/SLG/Ag NDs).By combining the plasmonic metallic nanostructures and the unique physical/chemical properties of graphene,Ag NPs/SLG/Ag NDs hybrid substrate was fabricated,and it exhibited extremely high surface-enhanced Raman scattering(SERS)*** tuning the diameter of Ag NDs,the SERS performance of Ag NPs/SLG/Ag NDs hybrid substrate has been systematically *** detection limit for rhodamine 6g(R6G)could reach the concentrations as low as 1×10^−12 mol/L,and the average enhancement factor(EF)of the Ag NPs/SLG/Ag NDs substrate could reach 5.65×10^*** advantages indicated that the Ag NPs/SLG/Ag NDs hybrid substrate could be regarded as a candidate for organic molecules detection under extremely low ***,spatial Raman mapping of Ag NPs/SLG/Ag NDs with 2.5μm diameter NDs showed the larger SERE signal existed around the rim of Ag NDs which was related to the localized surface *** phenomenon was contributed by a larger electromagnetic field which was tuned by Ag NPs and the edge of Ag *** mechanism also has been confirmed by the electromagnetic simulation result.

关键词： surface-enhanced Raman scattering(SERS) graphene high performance plasmon mapping

深埋长大隧道地温预测的机器学习算法对比研究

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安全与环境工程 2025年第1期32卷 137-147页

作者：周权罗锋柴波周爱国中国地质大学(武汉)地质调查研究院湖北武汉430074 中铁第一勘察设计院集团有限公司陕西西安710043

地热对隧道施工、工程结构及运营安全等均有较大的危害,随着我国基础设施建设布局西移,隧道建设的地质条件愈发复杂,隧道埋深和长度不断增加,隧道施工期高温热害问题频发。针对传统地温预测方法中预测精度不高、数据运用不充分,单一机... 详细信息

地热对隧道施工、工程结构及运营安全等均有较大的危害,随着我国基础设施建设布局西移,隧道建设的地质条件愈发复杂,隧道埋深和长度不断增加,隧道施工期高温热害问题频发。针对传统地温预测方法中预测精度不高、数据运用不充分,单一机器学习模型解译性差等问题,以A隧道为研究对象,将决策树(decision tree,DT)、支持向量机(support vector machine,SVM)、随机森林(random forest,RF)进行耦合,提出了基于DT-SVM-RF模型的深埋长大隧道地温预测方法。在分析隧道综合测井、地应力及岩石热物理试验、航空物探数据后,选取深度、声波波速等10个影响因子作为模型的输入,采用随机交叉验证和空间交叉验证对模型的鲁棒性、泛化能力进行检验,构建LASSO回归、随机森林、互信息3种回归模型,分析10个影响因子的特征重要性排序。结果表明:在测试集上多元线性回归、支持向量机、人工神经网络和决策树-支持向量机-随机森林(decision tree-support vector machinerandom forest,DT-SVM-RF)模型决定系数(R^(2))分别为0.76、0.91、0.88、0.93,均方误差MSE分别为17.64、6.25、8.46、5.20,DT-SVM-RF模型具有相对更优的预测性能,深度、岩石导温系数、岩石导热系数、最大水平主应力特征较为重要,说明DT-SVM-RF模型能有效地提高地温预测的准确率。研究结果可为类似隧道地温预测提供一种精度更高的可行新思路。

关键词：隧道热害隧道安全多元线性回归支持向量机(SVM) 随机森林(RF) 人工神经网络(ANN) 特征选择

Large-scale highly ordered periodic Au nano-discs/graphene and graphene/Au nanoholes plasmonic substrates for surface-enhanced Raman scattering

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Nano Research 2019年第11期12卷 2788-2795页

作者： Yansheng Liu feng luo IMDEA Nanoscience Faraday 9Ciudad Unriversitaria de CantoblancoMadrid 28049Spain

In this paper,the study of using masks to directly generate large area,highly ordered and periodical nanostructure has been *** Au nano-discs(NDs)arrays have been fabricated on top of graphene by using holey SigN4 mask which is directly fixed on top of graphene and Au metal is deposited through the holes in mask by thermal evaporation method under vacuum *** fabrication method provides an easy,fast and cost efficiency way to generate periodical ***,Au nanoholes(NHs)structure has been studied by using holey SigN4 as a *** surface-enhanced Raman scattering(SERS)sensitvities of periodical Au NDs/graphene and graphene/Au NHs hybrid structures have been systematically *** internal mechanisms could be explained by chemical mechanism effect of graphene and electromagnetic mechanism effect of metallic *** enhancement factors have been systematically investigated by varying the diameter and the thickness of Au discs and Au *** mappings of Au NDs with 2.5 um diameter ilustrate that the larger SERS enhancements exist in the rim of NDs which has good agreement with the electric field simulation *** SERE enhancement factors of fluorescein obtained from Au NDs/graphene substrates shows an improvement factor of 500%in comparison of graphene *** calculated SERS enhancement factors of graphene/Au NHs achieve 1,200%in comparison of graphene/planar Au film substrate.

关键词： graphene surface-enhanced Raman scattring(SERS) Au nano-discs(NDs) Au nanoholes(NHs) periodic

Coopetition between B2C E-commerce Companies:Price Competition and Logistics Service Cooperation

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Journal of Systems Science and Systems Engineering 2020年第6期29卷 730-752页

作者： Weixiang Huang Wenhui Zhou feng luo School of Business Administration South China University of TechnologyGuangzhou 510640China School of E-commerce and Logistics Beijing Technology and Business UniversityBeijing 100048China

This paper studies the impact of logistics cooperation in two competing companies,one of which is equipped with a self-run logistics system while the other is *** latter outsources logistics services to a third-party logistics company before logistics cooperation,or to its competitor after logistics cooperation with the client's service quality being in proportion to and no greater than the service provider's service *** find that when the service provider is a price taker,logistics cooperation is beneficial to both firms only when the service quality after logistics cooperation is ***,under some circumstances,the client's profit increases even when its service quality decreases after logistics cooperation because logistics cooperation eases the price *** also find that all-win situations in which logistics cooperation increases the firms7 profit,consumer surplus and social welfare can be ***,when the service price can be chosen by the service provider,we propose a negotiation process in which agreement on logistics cooperation can be reached;when the firm can invest in service quality,logistics cooperation may lower the equilibrium investment level.

关键词： E-commerce B2C coopetition logistics cooperation hotelling model

Design,synthesis and characterization of novel poly(urethane-urea) based on a macrodiol from poly(lactic acid) and poly(p-dioxanone)

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Chinese Chemical Letters 2011年第2期22卷 237-240页

作者： Yan feng luo Key Lab of Biorheological Science and Technology (Chongqing University) Ministry of Education College of Bioengineering Chongqing University Chongqing 400030 China Research Center of Bioinspired Material Science and Engineering College of Bioengineering Chongqing University Chongqing 400030 China Department of Biology Chongqing University of Science and Technology Chongqing 401331 China Received 29 June 2010

A series of novel poly（urethane-urea）（PUU） was synthesized from poly（lactide-co-p-dioxanone） macrodiol（HO-P（LA-co-PDO）-OH）, hexamethylene diisocyanate（HDI） and butanediamine（BDA）.The obtained PUU,which is recorded as P（LA-co-PDO）-PUU here,may demonstrate enhanced phase separation and thus improved shape memory *** was employed to characterize the copolymers,and the effects of NCO/OH molar ratios on Tg of PUU was investigated by means of differential scanning calorimetry （DSC）.The results revealed the successful synthesis of P（LA-co-PDO）-*** addition,the Tg of P（LA-co-PDO）-PUU increased from 37.9℃to 44.2℃with the increase NCO/OH ratios from 1.1 to *** P（LA-co-PDO）-PUU with Tg close to body temperature will have potential applications as shape memory polymers in biomedical fields,especially in minimally invasive surgery.

关键词： Poly(urethane-urea) Polylactic acid p-Dioxanone Butanediamine Shape memory polymer

Short-time maritime target detection based on polarization scattering characteristics

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Journal of Systems Engineering and Electronics 2024年第1期35卷 55-64页

作者： CHEN Shichao luo feng TIAN Min LYU Wanghan College of Computer and Information Engineering(College of Artificial Intelligence) Nanjing Tech UniversityNanjing 211816China Hangzhou Institute of Technology Xidian UniversityHangzhou 311200China

In this paper,a detection method combining Cameron decomposition based on polarization scattering characteristics in sea clutter background is ***,the Cameron decomposition is exploited to fuse the radar echoes of full polarization channels at the data *** to the artificial material structure on the surface of the target,it can be shown that the non-reciprocity of the target cell is stronger than that of the clutter ***,based on the analysis of the decomposition results,a new feature with scattering geometry characteristics in polarization domain,denoted as Cameron polarization decomposition scattering weight(CPD-SW),is extracted as the test statistic,which can achieve more detailed descriptions of the clutter scattering characteristics utilizing the difference between their scattering ***,the superiority of the proposed CPD-SW detector over traditional detectors in improving detection performance is verified by the IPIX measured dataset,which has strong stability under short-time observation in threshold detection and can also improve the separability of feature space zin anomaly detection.

关键词： sea clutter small target radar detection Cameron decomposition characteristics analysis

Rational tuning of thorium-organic frameworks by reticular chemistry for boosting radionuclide sequestration

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Nano Research 2022年第2期15卷 1472-1478页

作者： Han feng Xiaohong Xiong Lele Gong Huiping Zhang Ying Xu Xuefeng feng feng luo School of Chemistry Biology and Materials ScienceEast China University of TechnologyNanchang 330013China

The reticular chemistry strategy presents a powerful molecule-design tool to tailor the physical and chemical properties of metal-organic framework(MOF).In this work,we for the first time investigated the effect of organic ligands on the radionuclide sequestration(TcO_(4)^(-))of thorium-organic *** a coordination modulation technique,two novel isoreticular thorium-organic frameworks,namely Th-MOF-67 and Th-MOF-68,were *** to the antetype MOF of Th-MOF-66 that shows extremely low uptake of ReO_(4)^(-)(a chemical surrogate of radioactive TcO_(4)^(-)),the isoreticular MOFs of Th-MOF-67 and Th-MOF-68 enable ultrahigh uptake of ReO_(4)^(-),giving an impressively 36.8-fold or 56-fold enhancement,*** adsorption capacity of Th-MOF-68 is as high as 560 mg/g,exceeding most reported adsorbents for such *** mechanism for such exceptional outstanding performance,as unveiled by both the single crystal X-ray diffraction and theoretical calculation,is due to coordination interaction for Th-MOF-67,when a tetrazolate ligand was used,or a combined effect from both coordination interaction and anion-exchange for Th-MOF-68,if using a triazolate ligand.

关键词： thorium-organic framework ligand effect defect site anion exchange radionuclide sequestration

A critical transition rule for broadening exponent of fluctuation and its effect on dissipation in chemical reaction-heat conduction coupling systems

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Science China Chemistry 2011年第5期54卷 774-781页

作者： LIN feng ZHAO NanRong luo JiuLi Institute of Chemical Physics College of ChemistrySichuan UniversityChengdu 610064China

A stochastic model of chemical reaction-heat conduction-diffusion for a one-dimensional gaseous system under Dirichlet or zero-fluxes boundary conditions is proposed in this paper. Based on this model,we extend the theory of the broadening exponent of critical fluctuations to cover the chemical reaction-heat conduction coupling systems as an asymptotic property of the corresponding Markovian master equation (ME),and establish a valid stochastic thermodynamics for such systems. As an illustration,the non-isothermal and inhomogeneous Schl-gl model is explicitly studied. Through an order analysis of the contributions from both the drift and diffusion to the evolution of the probability distribution in the corresponding Fokker-Planck equation(FPE) in the approach to bifurcation,we have identified the critical transition rule for the broadening exponent of the fluctuations due to the coupling between chemical reaction and heat conduction. It turns out that the dissipation induced by the critical fluctuations reaches a deterministic level,leading to a thermodynamic effect on the nonequilibrium physico-chemical processes.

关键词： stochastic model of chemical reaction–heat conduction–diffusion systems stochastic thermodynamics of chemical reaction–heat conduction coupling processes broadening exponent of critical fluctuation entropy production of fluctuations fluctuation–dissipation effect