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Journal of Mountain Science 2024年第1期21卷 271-291页

作者： garcía-arias sergio VELANDIA Francisco ALVAREZ Angélica SANABRIA-GÓMEZ JoséD TARAZONA Yessenia VARGAS María Camila Escuela de Geología Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia Escuela de Física Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia

This work applies stress tensors inversions and quantification of fracture patterns along the Mesa de Los Santos, in the Eastern Cordillera of Colombia, to better understand the potential fluid flow. It thus contributes to the conceptual hydrogeological model. The area was subdivided into three blocks, separated by the NW Potreros and the Los Santos faults, having minor inner faults of different orientations. This separation facilitates the analysis of the fractures measured in the field, which in general show high dip angles and a conjugate geometry in the northern block, tension fractures(Mode I) in the central block, and a random distribution in the southwestern block. WinTensor treatment of slickensides yielded a maximum horizontal stress(SHmax) of 111o, which coincides with the WNW-ESE tensor observed from the conjugate and tension joints. We then used Frac Pa Q to generate interpolation maps of fracture intensity and density. The maps show the highest values in the central block and the lowest in the northern block,where the precipitation is higher, causing intensive rock weathering and homogenization of the fracture planes. Although the highest values of connectivity by line are found to the south of the mesa, we suggest the possibility of greater flow from the recharge zone(NE) along bedding planes and open NW-SE fractures.

关键词： Mesa de Los Santos Colombia Win-Tensor FracPaQ Strike-slip faults Fractured aquifers

Thermo-electro-mechanical microstructural interdependences in conductive thermoplastics

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npj Computational Materials 2023年第1期9卷 955-965页

作者： Javier Crespo-Miguel sergio Lucarini Angel arias Daniel garcia-Gonzalez Department of Continuum Mechanics and Structural Analysis Universidad Carlos III de MadridAvda.de la Universidad 3028911 LeganésMadridSpain Department of Civil and Environmental Engineering Imperial College of LondonSouth Kensington CampusLondon SW72AZUK

Additive manufacturing has enabled the design of thermoplastic components that provide structural support,electrical conductivity and heat generation modulated by mechanical *** mechanisms and interplays that govern the material response at the microstructural level remain,however,***,we develop an experimental method to characterise conductive filaments from a combined mechanical,electrical and thermal *** approach is used to unravel exciting material interplays of conductive polylactic *** overcome experimental limitations that prevent a complete microstructural analysis of the problem,we develop a full-field homogenisation framework and implement it for finite *** framework accounts for viscoplasticity,electrical and thermal conduction,convection and heat generation via Joule effect,as well as for the interdependences between *** experimental validation,the framework is applied to virtually optimise fabrication requirements to obtain desired properties in final products,i.e.,stiffer products,filaments with higher conductivities or with better sensing capabilities.

关键词： conductive electrical overcome

Kinematics ofmandibular advancement devices(MADs):Why do some MADs move the lower jaw backward duringmouth opening?

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Bio-Design and Manufacturing 2024年第5期7卷 637-650页

作者： Juan A.Cabrera Alex Bataller sergio Postigo Marcos garcía Mechanical Engineering Department University of Malaga29071 MalagaSpain

Mandibular advancement devices(MADs)are widely used treatments for obstructive sleep *** function by advancing the lower jaw to open the upper *** increase patient comfort,most patients allow the mouth to be ***,not all systems maintain the lower jaw in a forward position during mouth opening,which results in the production of a retrusion that favors the collapse of the upper ***,the kinematic behavior of the mechanism formed by the mandible-device assembly depends on jaw *** means that,during mouth opening,some devices cause lower jaw protrusion in some patients,but cause its retraction in *** this study,we report the behavior of well-known devices currently on *** do so,we developed a kinematic model of the lower jawdevice *** validated for all devices analyzed using a high-resolution camera *** results show that some of the devices analyzed here did not produce the correct behavior during patient mouth opening.

关键词： Mandibular advancement devices Lower jaw kinematics Sleep apnea

Invasive strategy in elderly patients with acute coronary syndrome in 2018: close to the truth?

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Journal of Geriatric Cardiology 2019年第2期16卷 114-120页

作者： sergio garcía-Blas Clara Bonanad Juan Sanchis Servei de Cardiologia Hospital Clínic Universitari de València INCLIVA Universitat de ValènciaCIBERCV

Elderly population constitutes an increasingly larger proportion of patients admitted for acute coronary syndromes(ACS).The optimal management of ACS in these patients is still a challenge due to their clinical peculiarities and the paucity of specific data,and they have been traditionally managed more conservatively mainly based on subjective *** ST^segment elevation acute myocardial infarction urgent reperfusion is the standard of care and there is no upper age *** non-ST segment elevation acute myocardial infarction evidence is controversial,incomplete and mainly focused on chronological *** a strict conservative strategy should be avoided,routine invasive strategy may reduce the occurrence of myocardial infarction and need for revascularization at follow-up with no established benefit in terms of *** characteristics associated with aging,such as comorbidities and frailty,further discriminate patient's risk beyond *** is scarce,but it suggests that these features may modulate the benefit of invasive strategy in this *** trials should clarify the optimal management of ACS based on these parameters.

关键词： Acute coronary syndromes Comorbidity Frailty Percutaneous coronary intervention The elderly

Robust hybrid bismuth perovskites as potential photocatalysts for overall water splitting

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Nano Research 2024年第5期17卷 4593-4601页

作者： Antonio J.Chacón-garcía Herme G.Baldovi Artem A.Babaryk Antonio Rodríguez-Diéguez sergio Navalón Yolanda Pérez Hermenegildo garcía Patricia Horcajada Advanced Porous Materials Unit IMDEA Energy InstituteAvda.Ramón y Cajal 328935 MóstolesMadridSpain Departamento de Química Universitat Politècnica de València46022 ValènciaSpain Departamento Química Inorgánica Universidad de Granada1807GranadaSpain Departamento de Biología y Geología Física y Química Inorgánica.ESCET.Universidad Rey Juan Carlos28933 MóstolesMadridSpain Instituto de tecnología química CSIC-UPV Universitat Politècnica de València(UPV)46022Spain

Organic-inorganic hybrid perovskites have gained great attention as promising photocatalysts for hydrogen ***,due to their poor stability in water,the use of aqueous hydrohalic acid solutions is specifically required for an efficient hydrogen ***,three novel photoactive lead-free hybrid perovskites based on bismuth and triazolium cations(denoted as IEF-15,IEF-16,and IEF-17(IEF stands for IMDEA energy frameworks))were synthesized and fully characterized(structural,compositional,optical,etc.).Further,these solids were proposed as photocatalysts for the challenging gas phase overall water splitting(OWS)***,IEF-16 thin films exhibited a remarkable photocatalytic activity in both H_(2) and O_(2) evolution,as a consequence of its appropriate bandgap and energy-band alignment,achieving hydrogen evolution rates ofμmol·g_(H_(2))^(-)1846 and 360 after 24 h under ultraviolet-visible(UV-vis)irradiation or simulated solar irradiation,*** study additionally highlights the remarkable structural and photochemical stability of IEF-16 under different operational conditions(*** volume,irradiation and temperature),paving the way for green hydrogen production from OWS using perovskite-based photocatalysts.

关键词： bismuth-based hybrid perovskites thin films photocatalysis overall water splitting green hydrogen

Shade coffee plantations maintain woody plant diversity and structure in a cloud forest landscape of southern Mexico

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Journal of Forestry Research 2021年第2期32卷 637-648页

作者： Edson AAlvarez-Alvarez R.Carlos Almazán-Nunez Fernando González-garcía Marlene Brito-Millán Alfredo Méndez-Bahena sergio garcía-Ibáñez Maestría en Recursos Naturales y Ecología Facultad de Ecología MarinaUniversidad Autónoma de Guerrero39390 AcapulcoGuerreroMexico Laboratorio Integral de Fauna Silvestre Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Red Biología y Conservación de Vertebrados Instituto de EcologíaA.C.CP 91073 XalapaVeracruzMexico University of California Institute for Mexico and the United States(UC MEXUS) Cuerpo Académico Biodiversidad y Gestión Ambiental SustentableFacultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Laboratorio de Biología de la Conservación Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Laboratorio de Ecología Cuantitativa Facultad de Ecología MarinaUniversidad Autónoma de Guerrero39390 AcapulcoGuerreroMexico

Cloud forest ecosystems of the Latin American tropics are highly threatened by changes in land-use such as expanding croplands and livestock pastures that promote shifts in the structure and composition of plant communities in these ***,shade coffee plantations represent a forest management alternative that has been shown to maintain biodiversity in these *** this study,we evaluated changes in the composition,diversity,and structure of Mexican cloud-forest woody species for three land use categories:cattle pastures,shade coffee plantations and advanced succession *** each category,fifteen 0.28-ha plots were established and the composition and diversity of vegetation was *** of species was analyzed using ordination methods,and alpha diversity was compared using Hill ***-seven woody species belonging to 40 families were *** richness and diversity was high in both the advanced successional forest and coffee plantations compared to cattle *** composition and structure was similar between late succession forests and coffee plantations with both land uses also being more structurally complex than cattle *** results show how shade coffee cultivation is a land-use activity that maintains woody plant communities in a manner that aligns with biodiversity conservation.

关键词： Land uses Late succession Plant diversity Shade coffee Vegetation structure

Science Letters:Visual odometry for road vehicles—feasibility analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 2017-2020页

作者： SOTELO Miguel-angel garcíA Roberto PARRA Ignacio FERNNDEZ David GAVILN Miguel LVAREZ sergio NARANJO José-eugenio Department of Electronics University of Alcalá Alcalá de Henares 28871 Spain Department of Informatics Industrial Automation Institute CSIC Madrid Spain

Estimating the global position of a road vehicle without using GPS is a challenge that many scientists look forward to solving in the near future. Normally, inertial and odometry sensors are used to complement GPS measures in an attempt to provide a means for maintaining vehicle odometry during GPS outage. Nonetheless, recent experiments have demonstrated that computer vision can also be used as a valuable source to provide what can be denoted as visual odometry. For this purpose, vehicle motion can be estimated using a non-linear, photogrametric approach based on RAndom SAmple Consensus (RANSAC). The results prove that the detection and selection of relevant feature points is a crucial factor in the global performance of the visual odometry algorithm. The key issues for further improvement are discussed in this letter.

关键词： 3D visual odometry Ego-motion estimation RAndom SAmple Consensus (RANSAC) Photogrametric approach

Multi-temporal NDVI analysis using UAV images of tree crowns in a northern Mexican pine-oak forest

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Journal of Forestry Research 2023年第6期34卷 1855-1867页

作者： JoséLuis Gallardo-Salazar Marcela Rosas-Chavoya Marín Pompa-garcía Pablito Marcelo López-Serrano Emily garcía-Montiel Arnulfo Meléndez-Soto sergio Iván Jiménez-Jiménez Instituto de Investigaciones Agropecuarias y Forestales Universidad Michoacana de San Nicolás de Hidalgo(UMSNH)58330 MoreliaMichoacánMexico Programa Institucional de Doctorado en Ciencias Agropecuarias y Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Instituto de Silvicultura e Industria de la Madera Universidad Juárez del Estado de DurangoBoulevard del Guadiana 501Ciudad UniversitariaTorre de Investigación34120 DurangoMéxico INIFAP-CENID RASPA Centro Nacional de Investigación Disciplinaria en Relación Agua-Suelo-Planta-Atmósfera Margen derecha canal Sacramento km 6.5Zona industrial35140 Gómez PalacioDurangoMexico

The use of unmanned aerial vehicles(UAV)for forest monitoring has grown significantly in recent years,providing information with high spatial resolution and temporal *** with multispectral sensors allow the use of indexes such as the normalized difference vegetation index(NDVI),which determines the vigor,physiological stress and photo synthetic activity of *** study aimed to analyze the spectral responses and variations of NDVI in tree crowns,as well as their correlation with climatic factors over the course of one *** study area encompassed a 1.6-ha site in Durango,Mexico,where Pinus cembroides,Pinus engelmannii,and Quercus grisea *** images were acquired with UAV and information on meteorological variables was obtained from NASA/POWER *** ANOVA explored possible differences in NDVI among the three *** correlation was performed to identify the linear relationship between NDVI and meteorological *** differences in NDVI values were found at the genus level(Pinus and Quercus),possibly related to the physiological features of the species and their *** grisea had the lowest NDVI values throughout the year which may be attributed to its sensitivity to relative humidity and *** the use of UAV with a multispectral sensor for NDVI monitoring allowed genera differentiation,in more complex forest analyses hyperspectral and LiDAR sensors should be integrated,as well other vegetation indexes be considered.

关键词： Multispectral images Normalized diff erence Vegetation index Phenology Unmanned aerial vehicles Multitemporal analysis

Bats and their vital ecosystem services:a global review

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Integrative Zoology 2022年第1期17卷 2-23页

作者： Leidy Azucena RAMÍREZ-FRÁNCEL Leidy Viviana garcÍA-HERRERA sergio LOSADA-PRADO Gladys REINOSO-FLÓREZ Alfonso SÁNCHEZ-HERNÁNDEZ sergio ESTRADA-VILLEGAS Burton KLIM Giovany GUEVARA Programa de Doctorado en Ciencias Biológicas&Grupo de Investigación en Zoología(GIZ) Facultad de CienciasUniversidad del TolimaIbaguéColombia Programa para la Conservación de los Murciélagos de Colombia BogotáD.C.Colombia Departamento de Biología&Grupo de Investigación en Zoología(GIZ) Facultad de CienciasUniversidad del TolimaIbaguéColombia Departamento de Matemáticas y Estadística Facultad de CienciasUniversidad del TolimaIbaguéColombia Yale School of the Environment Yale UniversityNew HavenConnecticutUSA Smithsonian Tropical Research Institute BalboaRepublic of Panama Department of Natural History Royal Ontario MuseumTorontoOntarioCanada

Bats play crucial ecosystem services as seed dispersers,pollinators,controllers of insects,and nutrient ***,there has not been a thorough global review evaluating these roles in bats across all biogeographical regions of the *** reviewed the literature published during the last two decades and identified 283 relevant studies:78 dealt with the control of potential insect pests by bats,80 related to the suppression of other arthropods,60 on the dispersal of native or endemic seeds,11 dealt with the dispersal of seeds of introduced plants,29 on the pollination of native or endemic plants,1 study on pollination of introduced plants,and 24 on the use of guano as *** literature search showed that queries combining the terms“seed dispersal,”“insectivorous bats,”“nectarivorous bats,”“use of guano,”and“ecosystem services”returned 577 studies,but half were experimental in *** found that the evaluation of ecosystem services by bats has been mostly conducted in the Neotropical and Palearctic *** detect differences across relevant studies,and to explain trends in the study of ecosystem services provided by bats,we performed generalized linear mixed models(GLMM)fitted with a Poisson distribution to analyze potential differences among sampling *** identified 409 bat species that provide ecosystem services,752 insect species consumed by bats and 549 plant species either dispersed or pollinated by *** review summarizes the importance of conserving bat populations and the ecological services they provide,which is especially important during the current pandemic.

关键词： chiroptera ecosystem services frugivory,guano,insectivory nectarivory pest control pollination seed dispersal

An Optimal Design Method Based on Small Amplitude Homogenization

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 843-854页

作者： sergio GUTIERREZ Department of Structural and Geotechnical Engineering Pontificia Universidad Catolica de Chile

An optimal design method for two materials based on small amplitude homogenization is presented. The method allows to use quite general objective functions at the price that the two materials should have small contrasts in their relevant physical parameters. The following two applications are shown: Stress constrained compliance minimization and defect location in elastic bodies.

关键词： Homogenization Inverse problems Relaxation Stress concentration