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Antibacterial approaches in tissue engineering using metal ions and nanoparticles:From mechanisms to applications

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Bioactive Materials 2021年第12期6卷 4470-4490页

作者： Maria Godoy-Gallardo Ulrich Eckhard luis M.Delgado Yolanda J.D.de Roo puente Mireia Hoyos-Nogués F.Javier Gil Roman A.Perez Bioengineering Institute of Technology Universitat Internacional de CatalunyaCarrer de Josep Trueta08195del VallèsSant CugatBarcelonaSpain Proteolysis Lab Department of Structural BiologyMolecular Biology Institute of BarcelonaCSICBarcelona Science ParkBaldiri Reixac 15-2108028BarcelonaSpain

Bacterial infection of implanted scaffolds may have fatal consequences and,in combination with the emergence of multidrug bacterial resistance,the development of advanced antibacterial biomaterials and constructs is of great interest.Since decades ago,metals and their ions had been used to minimize bacterial infection risk and,more recently,metal-based nanomaterials,with improved antimicrobial properties,have been advocated as a novel and tunable alternative.A comprehensive review is provided on how metal ions and ion nanoparticles have the potential to decrease or eliminate unwanted bacteria.Antibacterial mechanisms such as oxidative stress induction,ion release and disruption of biomolecules are currently well accepted.However,the exact antimicrobial mechanisms of the discussed metal compounds remain poorly understood.The combination of different metal ions and surface decorations of nanoparticles will lead to synergistic effects and improved microbial killing,and allow to mitigate potential side effects to the host.Starting with a general overview of antibacterial mechanisms,we subsequently focus on specific metal ions such as silver,zinc,copper,iron and gold,and outline their distinct modes of action.Finally,we discuss the use of these metal ions and nanoparticles in tissue engineering to prevent implant failure.

关键词： Metal ions Metal nanoparticles Mechanism of action Antibacterial activity Tissue engineering Biomaterials applications

基于面跳跃方法的半导体纳米材料从头算非绝热分子动力学研究

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Chinese Journal of Chemical Physics 2022年第1期35卷 16-37,I0062页

作者：雷玉立马海波 luis Vasquez 南京大学化学化工学院南京210023

在光电子学应用中,器件性能主要取决于半导体纳米材料中的光生载流子动力学过程.但是,受反应速率、材料表面积、材料组成等多种因素影响,描述其中的动力学过程非常具有挑战性.模拟光生载流子动力学过程可以通过绝热分子动力学方法实现,... 详细信息

在光电子学应用中,器件性能主要取决于半导体纳米材料中的光生载流子动力学过程.但是,受反应速率、材料表面积、材料组成等多种因素影响,描述其中的动力学过程非常具有挑战性.模拟光生载流子动力学过程可以通过绝热分子动力学方法实现,即求解包含非绝热耦合项的含时薛定谔方程.在众多绝热分子动力学方法中,面跳跃方法出色地平衡了计算精度和计算成本,因而成为描述半导体纳米材料中不同非绝热过程间竞争的有力工具,已被用来模拟材料中的超快动力学过程和其他复杂效应,如Janus过渡金属二硫族化合物范德华异质结中的电荷分离.本综述通过介绍该领域代表性的理论及实验工作,阐述了光生载流子对半导体纳米材料性能的重要影响,以及面跳跃方法在描述其动力学行为中的重要作用.山于日趋复杂的材料体系对理论工作提出了巨大的挑战,本综述重点介绍了最近用于模拟这些复杂材料的一些创性的新方法,包括高精度的电子结构方法和与之相结合的绝热分子动力学方法.

关键词：面跳跃非绝热动力学半导体纳米材料凝聚相系统经典路径近似

All-optical nonlinear chiral ultrafast magnetization dynamics driven by circularly polarized magnetic fields

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High Power Laser Science and Engineering 2023年第6期11卷 154-161页

作者： luis Sánchez-Tejerina Rodrigo Martín-Hernández Rocío Yanes luis Plaja luis López-Díaz Carlos Hernández-García Grupo de Investigación en Aplicaciones del Láser y Fotónica Departamento de Física AplicadaUniversidad de SalamancaSalamancaSpain Present address:Departamento de Electricidad y Electrónica Universidad de ValladolidValladolidSpain Departamento de Física Aplicada Universidad de SalamancaSalamancaSpain Unidad de Excelencia en Luz y Materia Estructuradas(LUMES) Universidad de SalamancaSalamancaSpain

Ultrafast laser pulses provide unique tools to manipulate magnetization dynamics at femtosecond timescales,where the interaction of the electric field usually dominates over the magnetic field.Recent proposals using structured laser beams have demonstrated the possibility to produce regions where intense oscillating magnetic fields are isolated from the electric field.In these conditions,we show that technologically feasible tesla-scale circularly polarized high-frequency magnetic fields induce purely precessional nonlinear magnetization dynamics.This fundamental result not only opens an avenue in the study of laser-induced ultrafast magnetization dynamics,but also sustains technological implications as a route to promote all-optical non-thermal magnetization dynamics both at shorter timescales-towards the subfemtosecond regime-and at THz frequencies.

关键词： chiral behavior nonlinear dynamics ultrafast dynamics

Singular Integrals with Variable Kernels in Dyadic Settings

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Acta Mathematica Sinica,English Series 2023年第8期39卷 1565-1579页

作者： Hugo AIMAR Raquel CRESCIMBENI luis NOWAK IMAL-CONICET and UNL Santa FeArgentina Departamento de Matemática FaEAUNCo.and IITCI-CONICETNeuquenArgentina

In this paper we explore conditions on variable symbols with respect to Haar systems,defining Calderón–Zygmund type operators with respect to the dyadic metrics associated to the Haar bases. We show that Petermichl’s dyadic kernel can be seen as a variable kernel singular integral and we extend it to dyadic systems built on spaces of homogeneous type.

关键词： Singular integrals spaces of homogeneous type Petermichl’s operator Haar basis

A renewal theory based performance and configuration framework of the IEEE 802.11ah RAW mechanism

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Digital Communications and Networks 2023年第1期9卷 236-251页

作者： Hamid Taramit luis Orozco-Barbosa Abdelkrim Haqiq Hassan First University of Settat Faculty of Sciences and TechniquesComputerNetworksMobility and Modeling Laboratory:IR2M26000 SettatMorocco Albacete Research Institute of Informatics Universidad de Castilla-La Mancha02006 AlbaceteSpain

IEEE 802.11ah is a new Wi-Fi standard for sub-1Ghz communications,aiming to address the challenges of the Internet of Things(IoT).Significant changes in the legacy 802.11 standards have been proposed to improve the network performance in high contention scenarios,the most important of which is the Restricted Access Window(RAW)mechanism.This mechanism promises to increase the throughput and energy efficiency by dividing stations into different groups.Under this scheme,only the stations belonging to the same group may access the channel,which reduces the collision probability in dense scenarios.However,the standard does not define the RAW grouping strategy.In this paper,we develop a new mathematical model based on the renewal theory,which allows for tracking the number of transmissions within the limited RAW slot contention period defined by the standard.We then analyze and evaluate the performance of RAW mechanism.We also introduce a grouping scheme to organize the stations and channel access time into different groups within the RAW.Furthermore,we propose an algorithm to derive the RAW configuration parameters of a throughput maximizing grouping scheme.We additionally explore the impact of channel errors on the contention within the time-limited RAW slot and the overall RAW optimal configuration.The presented analytical framework can be applied to many other Wi-Fi standards that integrate periodic channel reservations.Extensive simulations using the MATLAB software validate the analytical model and prove the effectiveness of the proposed RAW configuration scheme.

关键词： IEEE 802.11ah Performance evaluation Renewal theory RAW mechanism Internet of things

胃食管反流病在智利南部的患病率:一项基于人群的横断面研究

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Gastroenterology Report 2020年第4期8卷 286-292,I0001,I0002页

作者： Carlos Manterola luis Grande luis Bustos Tamara Otzen Center of Morphological and Surgical Studies Universidad de La FronteraTemucoChile Department of Surgery Universidad de La FronteraTemucoChile Department of Surgery Hospital del MarUniversitat Auto`noma de BarcelonaBarcelonaSpain Department of Public Health Universidad de La FronteraTemucoChile

背景:本研究旨在评估智利南部Temuco地区成人胃食管反流病(GERD)患病率,并分析与GERD相关的人口统计学因素。方法:本研究开展于2017年,采用一种已被证明有效的GERD问卷,对智利南部Temuco地区的普通人群进行横断面调查。Temuco城区有245,... 详细信息

背景:本研究旨在评估智利南部Temuco地区成人胃食管反流病(GERD)患病率,并分析与GERD相关的人口统计学因素。方法:本研究开展于2017年,采用一种已被证明有效的GERD问卷,对智利南部Temuco地区的普通人群进行横断面调查。Temuco城区有245,317名居民,城区分为四个区域,代表着不同的社会经济水平。按52.8%的GERD患病率、3.0%的准确率、95.0%的可信区间及1.15的设计效应估算所需样本量。通过地区抽样建立组群,计算GERD患病率,并通过两变量及多因素分析评估其影响因素。结果:从四个区域共计纳入了1,069名研究对象(女性占47.9%,中位年龄40岁)进行问卷调查。GERD患病率为44.8%。最常诉及的症状是反流。1/3的研究对象采用了药物来控制症状,按照问卷评估,这些人均被认为患有GERD,尽管其中68%的人从未就医。GERD的发生与年龄(P<0.001)和性别显著相关(P=0.001)。结论:在本项基于人群的研究中,GERD患病率高达44.8%,其发生与年龄和性别有关。

关键词： gastroesophageal reflux disease prevalence cross-sectional studies evidence-based medicine clinical epidemiology

Linear viscoelastic behavior of asphalt binders and mixtures containing very high percentages of reclaimed asphalt pavement

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Frontiers of Structural and Civil Engineering 2023年第8期17卷 1211-1227页

作者： Reza IMANINASAB luis LORIA-SALAZAR Alan CARTER Construction Engineering Department École de Technologie Supérieure(ÉTS)University of QuebecMontreal H3C 1K3Canada Civil Engineering Department Universidad Isaac NewtonSan José10108Costa Rica

The primary aim of this study is to correlate the impact of aggregates,if any,on the viscoelastic behavior of rejuvenated asphalt mixtures containing very high amounts of reclaimed asphalt pavement(RAP)(>50%).First,gradation of 100%RAP was rectified,using a modified Bailey method by adding virgin aggregates to achieve two coarse dense-graded and one fine dense-graded blends.Complex modulus test was then performed from−35 to+35℃and 0.01–10 Hz.In addition to performance grade(PG)testing,extracted and recovered binders from different asphalt mixtures underwent shear complex modulus test within−8℃to high temperature PG and frequencies from 0.001 to 30 Hz.Cole−Cole,Black space,complex modulus and phase angle master curves were constructed and ShiftHomothety-Shift in time-Shift(SHStS)transformation was used to compare the linear viscoelastic behavior of asphalt binders and mixtures.The influence of aggregates on the viscoelastic behavior of asphalt mixtures depends on temperature and/or frequency.The role of asphalt binders in the behavior of asphalt mixtures is more pronounced at high temperatures and the effect of the aggregate structure increases as the temperature falls.The maximum difference(60%to 70%)in the viscoelastic behavior of the binder and mixture based on SHStS transformed Cole−Cole curves is within the phase angle of 15°–20°.

关键词： RAP complex modulus SHStS transformation rejuvenation behavior of asphalt binder and mixture

What Isat Stake in Comparing the Literatures?

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外国语言与文化(英文) 2023年第1期7卷 53-64页

作者： Jose luis Jobim Fluminense Federal University

This paper will present and discuss a few questions raised in David Damrosch's Comparing the Literatures:Literary Studies in a Global Age,a book that,divided into chapters based on some selected keywords,develops rele... 详细信息

关键词： comparative literature translation world literature trasnational literary experience linguistic imperialism

New frontiers on open standards for geo-spatial science

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Geo-Spatial Information Science 2017年第2期20卷 126-133页

作者： luis Bermudez Open Geospatial Consortium WaylandMAUSA

The process of sharing of data has become easier than ever with the advancement of cloud computing and software tools.However,big challenges remain such as efficient handling of big geospatial data,supporting and sharing of crowd sourced/citizen science data,integration with semantic heterogeneity,and inclusion of agile processes for continuous improvement of geospatial technology.This paper discusses the new frontiers regarding these challenges and the related work performed by the Open Geospatial Consortium,the world leading organization focused on developing open geospatial standards that“geo-enable”the Web,wireless,and location-based services and mainstream IT.

关键词： Open Geospatial Consortium(OGC) big data cloud computing open standards semantics linked data