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Surgical left atrial appendage occlusion during cardiac surgery： A systematic review and meta-analysis

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World Journal of Cardiology 2018年第11期10卷 242-249页

作者： Varunsiri Atti Mahesh Anantha-Narayanan Mohit K Turagam Scott Koerber Sunil Rao juan fviles-gonzalez Rakesh MSuri Poonam Velagapudi Dhanunjaya Lakkireddy David G Benditt Department of Medicine Michigan State University-Sparrow Hospital East Lansing MI 48912 United States Division of Cardiovascular diseases Department of Medicine University of Minnesota Minneapolis MN 55455 United States Helmsley Electrophysiology Center Icahn School of medicine at Mount Sinai New York City NY 10029 United States Department of Cardiac Electrophysiology Medical University of South Carolina Charleston SC 29425 United States Department of Cardiovascular diseases Genesys Heart Institute Ascension Genesys Hospital Grand Blanc MI. Baptist Health South Florida Professor of Medicine at Wertheim College of Medicine Miami FL 33176. Cleveland Clinic Foundation and Cleveland Clinic Abu Dhabi Department of Thoracic and Cardiovascular Surgery. Cleveland Clinic Cleveland OH 44195 United States Structural Heart and Valve Center Center for Interventional Vascular Therapy Division of Cardiology Columbia University Medical Center New York City NY 10027 United States Kansas City Heart Rhythm Institute and Research Foundation Kansas City MO 64132 United States

AIM To evaluate the safety and efficacy of surgical left atrial appendage occlusion(s-LAAO) during concomitant cardiac *** We performed a comprehensive literature search through May 31 st 2018 for all eligible studies comparing s-LAAO vs no occlusion in patients undergoing cardiac surgery. Clinical outcomes during follow-up included: embolic events, stroke, all-cause mortality, atrial fibrillation(AF), reoperation for bleeding and postoperative complications. We further stratified the analysis based on propensity matched studies and AF *** Twelve studies(n = 40107) met the inclusion criteria.s-LAAO was associated with lower risk of embolic events(OR: 0.63, 95%CI: 0.53-0.76; P < 0.001) and stroke(OR: 0.68, 95%CI: 0.57-0.82; P < 0.0001).Stratified analysis demonstrated this association was more prominent in the AF predominant strata. There was no significant difference in the incidence risk of allcause mortality, AF, and reoperation for bleeding and postoperative *** Concomitant s-LAAO during cardiac surgery was associated with lower risk of follow-up thromboembolic events and stroke, especially in those with AF without significant increase in adverse events. Further randomized trials to evaluate long-term benefits of s-LAAO are warranted.

关键词： Left atrial appendage Left atrial appendageocclusion Embolic events Stroke Adverse events

Effect of Nanostructures Addition and Enhancement of Poly (Vinylidene Difluoride) (PVDF) Energy Harvesting

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Materials Sciences and Applications 2024年第7期15卷 228-244页

作者： Omar Peña-Oliveras Brenda Javier-Boodhan Anthony La Santa juan gonzalez-Sanchez Division of Science Technology and Engineering Universidad Ana G. Mndez Carolina Campus Carolina Puerto Rico Department of Electronics University of Puerto Rico Bayamon Campus Bayamon Puerto Rico

With concerns in energy crisis and global warming, researchers are actively investigating alternative energy renewable solutions. Among the various methods, piezoelectric transduction stands out due to its impressive electromechanical coupling factor and coefficient. As a result, piezoelectric energy harvesting has garnered significant attention from the scientific community. In this study, we explored methods to enhance the piezoelectric properties of polyvinylidene fluoride (PVDF) through two distinct approaches. The first approach involved applying external high voltages at various stages during the mixture reaction. The goal was to determine whether this voltage application could alter or enhance PVDF’s piezoelectric conformation by improving the alignment of polarized dipoles. In the second part of our study, we investigated the effects of incorporating various nanostructures (including Iron Oxide, Magnesium Oxide, and Zinc Oxide) into PVDF. To analyze changes in PVDF’s crystalline structure, we utilized Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) techniques. Additionally, we measured the electric polarization of samples using a Precision LC Meter and examined the morphology of nanofibers through Scanning Electron Microscopy (SEM).

关键词： Poly (Vinylidene Fluoride) (PVDF) Energy Harvesting Electrospinning Nanoparticles ZnO MgO Fe3O4

Vertical Displacement Measurement in a Slow-Moving Sinkhole Using BOTDA

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Photonic Sensors 2024年第1期14卷 23-39页

作者： Pascual SEVILLANO Javier PRECIADO-GARBAYO Jorge SEVIL Francisco GUTIERREZ juan JMARTiNEZ Sonia MARTiN-LOPEZ Miguel gonzalez-HERRAEZ Aragon Institute of Engineering Research(I3A) Universidad de ZaragozaZaragoza 50018Spain Electronic Enginering and Communicaton Dpartment EINAUniversidad de ZaragzaZaragza 50018Spain Aragon Photonics Labs. Zaragoza 50009Spain Department of Earth Sciences Universidad de ZaragozaZaragoza 50009Spain Department of Electronics Escuela Politecnica SuperiorUniversidad de AlcalaMadrid 28805Spain

The effectiveness of monitoring and early-warning systems for ground deformation phenomena,such as sinkholes,depends on their ability to accurately resolve the ongoing ground displacement and detect the subtle deformation preceding catastrophic *** sinkholes with a slow subsidence rate and diffuse edges pose a significant challenge for subsidence monitoring due to the low deformation rates and limited lateral strain *** this work,we satisfactorily illustrate the practicality of the Brillouin optical time domain analysis(BOTDA)to measure the spatial-temporal patterns of the vertical displacement in such challenging slow-moving sagging *** assess the performance of the approach,we compare the strain recorded by the distributed optical fiber sensor with the vertical displacement measured by high-precision *** results show a good spatial correlation with the ability to identify the maximum subsidence *** is also a good temporal correlation with the detection of an acceleration phase in the subsidence associated with a flood event.

关键词： Distributed fiber optic sensing(DFOS) vertical displacement measurement slow subsidence rate sinkhole hazard early-warning system

Generation of lossy mode resonances(LMR)using perovskite nanofilms

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Opto-Electronic Advances 2024年第2期7卷 33-40页

作者： Dayron Armas Ignacio R.Matias M.Carmen Lopez-gonzalez Carlos Ruiz Zamarreño Pablo Zubiate Ignacio del Villar Beatriz Romero Electrical Electronic and Communications Engineering DepartmentPublic University of NavarraPamplona 31006Spain Institute of Smart Cities(ISC) Public University of NavarraPamplona 31006Spain Experimental Science and Technology School Rey Juan Carlos UniversityMostoles 28933Spain

The results presented here show for the first time the experimental demonstration of the fabrication of lossy mode resonance(LMR) devices based on perovskite coatings deposited on planar waveguides. Perovskite thin films have been obtained by means of the spin coating technique and their presence was confirmed by ellipsometry, scanning electron microscopy, and X-ray diffraction testing. The LMRs can be generated in a wide wavelength range and the experimental results agree with the theoretical simulations. Overall, this study highlights the potential of perovskite thin films for the development of novel LMR-based devices that can be used for environmental monitoring, industrial sensing, and gas detection, among other applications.

关键词： perovskite thin films slab waveguide lossy mode resonance

Rectal cancer treatment: improving the picture

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World Journal of Gastroenterology 2007年第44期13卷 5805-5812页

作者： juan A Diaz-gonzalez Leire Arbea Javier Aristu Department of Oncology Clinica Universitaria Universtity of Navarra Pamplona 31080 Spain

Multidisciplinary approach for rectal cancer treatment is currently well defined. Nevertheless, new and promising advances are enriching the portrait. Since the US NIH Consensus in the early 90's some new characters have been added. A bird's-eye view along the last decade shows the main milestones in the development of rectal cancer treatment protocols. New drugs, in combination with radiotherapy are being tested to increase response and tumor control outcomes. However, therapeutic intensity is often associated with toxicity. Thus, innovative strategies are needed to create a better-balanced therapeutic ratio. Molecular targeted therapies and improved technology for delivering radiotherapy respond to the need for accuracy and precision in rectal cancer treatment.

关键词： Rectal cancer Chemoradiotherapy Intensitymodulated radiation therapy Molecular targeted therapy

Assessing a novel modelling approach with high resolution UAV imagery for monitoring health status in priority riparian forests

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Forest Ecosystems 2021年第4期8卷 810-830页

作者： juan Guerra-Hernandez Ramon A.Diaz-Varela juan Gabriel Avarez-gonzalez Patricia Maria Rodriguez-gonzalez edata Centro de iniciativas empresariaisFundacion CEL.O Palomar s/n27004 LugoSpain Forest Research Centre School of AgricultureUniversity of LisbonInstituto Superior de Agronomia(ISA)Tapada da Ajuda1349-017 LisbonPortugal Biodiversity and Applied Botany Unit(GI BIOAPLIC 1809) Department of BotanyEscuela Politecnica SuperiorR/Benigno LedoUniversity of Santiago de CompostelaCampus Universitario27002 LugoSpain Sustainable Forest Management Unit(UXFS) Department of Agroforestry EngineeringEscuela Politecnica SuperiorR/Benigno LedoUniversity of Santiago de CompostelaCampus UniversitarioE-27002 LugoSpain

Background:Black alder(Alnus glutinosa)forests are in severe decline across their area of distribution due to a disease caused by the soil-borne pathogenic Phytophthora alni species complex(class Oomycetes),“alder Phytopththora”.Mapping of the different types of damages caused by the disease is challenging in high density ecosystems in which spectral variability is high due to canopy *** obtained by unmanned aerial vehicles(UAVs)may be particularly useful for such tasks due to the high resolution,flexibility of acquisition and cost efficiency of this type of *** this study,*** decline was assessed by considering four categories of tree health status in the field:asymptomatic,dead and defoliation above and below a 50% threshold.A combination of multispectral Parrot Sequoia and UAV unmanned aerial vehicles-red green blue(RGB)data were analysed using classical random forest(RF)and a simple and robust three-step logistic modelling approaches to identify the most important forest health indicators while adhering to the principle of parsimony.A total of 34 remote sensing variables were considered,including a set of vegetation indices,texture features from the normalized difference vegetation index(NDVI)and a digital surface model(DSM),topographic and digital aerial photogrammetry-derived structural data from the DSM at crown ***:The four categories identified by the RF yielded an overall accuracy of 67%,while aggregation of the legend to three classes(asymptomatic,defoliated,dead)and to two classes(alive,dead)improved the overall accuracy to 72% and 91% *** the other hand,the confusion matrix,computed from the three logistic models by using the leave-out cross-validation method yielded overall accuracies of 75%,80% and 94% for four-,three-and two-level classifications,***:The study findings provide forest managers with an alternative robust classification method for the rapid,effective assessment of area

关键词： Alder RPAS Multi-spectral Defoliation Texture variables 3D point cloud Tree health monitoring

Alliance Free and Alliance Cover Sets

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Acta Mathematica Sinica,English Series 2011年第3期27卷 497-504页

作者： juan Alberto RODRIGUEZ-VELAZQUEZ Jose Maria SIGARRETA Ismael gonzalez YERO Sergio BERMUDO Departament d'Enginyeria Informdtica i Matematiques Universitat Rovira i Virgili Av. Paisos Catalans 26 43007 Tarragona Spain Faculty of Mathematics Autonomous University of Guerrero Carlos E. Adame 5 Col. La Garita Acapuleo Guerrero Mexico Departament d'Enginyeria Informatica i Matematiques Universitat Rovira i Virgili Av. Pai'sos Catalans 26 43007 Tarragona Spain Department of Economy Quantitative Methods and Economic History Pablo de Olavide University Carretera de Utrera Kin. 1 41013 Sevilla Spain

A defensive （offensive） k-alliance in F = （V, E） is a set S C V such that every v in S （in the boundary of S） has at least k more neighbors in S than it has in V ／ S. A set X C_ V is defensive （offensive） k-alliance free, if for all defensive （offensive） k-alliance S, S／ X ≠ 0, i.e., X does not contain any defensive （offensive） k-alliance as a subset. A set Y C V is a defensive （offensive） k-alliance cover, if for all defensive （offensive） k-alliance S, S ∩ Y ≠ 0, i.e., Y contains at least one vertex from each defensive （offensive） k-alliance of F. In this paper we show several mathematical properties of defensive （offensive） k-alliance free sets and defensive （offensive） k-alliance cover sets, including tight bounds on their cardinality.

关键词： Defensive alliance offensive alliance alliance free set alliance cover set

A coupled fluid FEM-DEM technique for predicting blasting operations in tunnels

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Underground Space 2018年第4期3卷 310-316页

作者： Francisco Zarate Jose M.gonzalez juan Miquel Rainald Lohner Eugenio Onate Centre Internacional de Metodes Numerics en Enginyeria(CIMNE) Spain Universitat Politecnica de Catalunya(UPC) Gran Capitan s/nCampus Nord08034 BarcelonaSpain George Mason University USA1

We present recent developments in the coupling of the finite element method(FEM)and the discrete element method(DEM)for the analysis of rock blasting operations in *** coupled FEM-DEM technique has been proven to be an efficient procedure for pre-dicting the multiple fractures of rock induced by the loads generated in *** coupled FEM-DEM procedure is applied in tunnel construction,as well as to gas pressure blasting pyrotechnics to break rocks for the excavation of the tunnel *** the latter case,the effect of gas explosion is modeled by solving the equations of gas dynamics in the analysis domain using *** effect of gas forces in the underlying rock mass is modeled via an embedded fluid-structure interaction *** efficiency of the coupled FEM-DEM tech-nique is demonstrated in several examples of fracture tests and rock blasting problems related to tunnel *** examples pre-sented indicate that the combination of the DEM with simple three-node linear triangular elements(for two-dimensional problems)captures the onset of fractures and their evolution accurately,accounting for the penetration of gas in the failure domain(Zarate&Onate,2015;Zarate,Cornejo,&Onate,2018).

关键词： Discrete elements Finite elements Fracture mechanics FEM-DEM Gas dynamics

HEART RATE VARIABILITY DURING HIGH-INTENSITY EXERCISE

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Journal of Systems Science & Complexity 2013年第1期26卷 104-116页

作者： SARMIENTO Samuel GARCIA-MANSO juan Manuel MARTIN-gonzalez juan Manuel VA-AMONDE Diana CALDERóN Javier DA SILVA-GRIGOLETTO Marzo Edir Department of Physical Education University of Las Palmas de Gran Canaria Spain. Physics Department University of Las Palmas de Gran Canaria Spain. Department of Morphological Sciences School of Medicine University of Cdrdoba Spain. Physical Activity Sciences Faculty Polytechnic University of Madrid Spain. Andalusian Centre of Sports Medicine Cdrdoba Spain.

The aim of this paper is to describe and analyse the behaviour of heart rate variability(HRV)during constant-load,high-intensity exercise using a time frequency analysis(Wavelet Transform).Eleven elite cyclists took part in the study(age:18.6±3.0 years;VO_(2max):4.88±0.61 litres·min^(-1)).Initially,all subjects performed an incremental cycloergometer test to determine load power in a constant load-test(379.55±36.02 W;89.0%).HRV declined dramatically from the start of testing(p<0.05).The behaviour of power spectral density within the LF band mirrored that of total energy,recording a significant decrease from the outset LF peaks fell rapidly thereafter,remaining stable until the end of the ***-VHF fell sharply in the first 20 to 30 *** relative weighting(%) of HF-VHF was inverted with the onset of fatigue,[1.6%at the start,7.1(p<0.05) at the end of the first phase,and 43.1%(p<0.05) at the end of the test].HF-VHF_(peak) displayed three phases:a moderate initial increase,followed by a slight fall,thereafter increasing to the end of the *** LF/HF-VHF ratio increased at the start,later falling progressively until the end of the first phase and remaining around minimal values until the end of the test.

关键词： Cycling heart rate variability wavelet.