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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

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Temporal Variation of the Pelagic Copepod Community in Acapulco Bay, México

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Open Journal of Marine Science 2016年第1期6卷 40-48页

作者： Agustín A. Rojas-Herrera Juan Violante-González sergio garcía-ibáñez Salvador Villerías-Salinas Giovanni Moreno-Díaz Unidad Académica de Ecología Marina Universidad Autónoma de Guerrero Acapulco México Centro de Investigación y Posgrado en Estudios Socioterritoriales Universidad Autónoma de Guerrero Chilpancingo México

Between September 2009 and April 2010, superficial samples of plankton were collected in Acapulco Bay, using 150-μm mesh net, with the objective of studying the temporal variation in the abundance, species composition of the copepod community, and their relationship with some environmental parameters. Twenty-nine species of four orders were identified: 11 of Calanoida, 4 of Cyclopoida, 3 of Harpacticoida and 11 of Poecilostomatoida. A multivariate analysis (PCA) used to detect association between the abundance of copepod populations, and the environmental conditions through time, indicates a marked effect of the temperature and salinity parameters, on the abundance of the four copepod groups. The calanoids dominated numerically during most of the sampling months. The more important copepods genus were Corycaeus (7 species), andOithona (4 species). Nevertheless that the abundance of all copepod groups was affected temporarily by variations in the environmental conditions, the species composition inside the copepods community remained very stable.

关键词： Copepod Community Temporal Variation Acapulco Bay Mexico

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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

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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

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Quality of public space and sustainable development goals:analysis of nine urban projects in Spanish cities

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Frontiers of Architectural Research 2023年第3期12卷 477-495页

作者： Raimundo BambóNaya Pablo de la Cal Nicolás Carmen Díez Medina Isabel ezquerra sergio garcía-Pérez Javier Monclús Departamento de Arquitectura Universidad de ZaragozaZaragoza 50018Spain Instituto Universitario de Investigación en Patrimonio y Humanidades(IPH) Universidad de ZaragozaZaragoza 50018Spain

The starting point of this research is the urban model promoted by the United Nations through the Sustainable Development Goals(SDGs).The importance of public spaces is especially highlighted in Goal 11.7:“provide universal access to safe,inclusive,and accessible,green,and public spaces.”The quality of public spaces can be properly assessed by reconsidering the quality indicators and investigating their development potential,which is the main focus of our *** study is based on a theoretical and methodological reflection on the quality of public space,considering the contributions of some contemporary urban traditions and a few recent *** this perspective,a variety of public space projects developed in the European sphere have been selected and *** quality parameters identified in this initial analysis were then applied to the analysis of nine representative case studies in three Spanish cities(Madrid,Barcelona,and Zaragoza).The main goal is to propose a methodology that helps to evaluate the quality of those public spaces and determine its relationship with the safety,accessibility,and inclusiveness conditions they offer.

关键词： Safety Inclusiveness Accessibility Design strategy Urban project

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A Numerical Study on Hydraulic Fracturing Problems via the Proper Generalized Decomposition Method

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Computer Modeling in Engineering & Sciences 2020年第2期122卷 703-720页

作者： Daobing Wang sergio Zlotnik Pedro Díez Hongkui Ge Fujian Zhou Bo Yu School of Mechanical Engineering Beijing Key Laboratory of Pipeline Critical Technology and Equipment for Deepwater Oil&Gas DevelopmentBeijing Institute of Petrochemical TechnologyBeijing102617China. Laboratori de Càlcul Numèric(LaCàN) ETS de Ingeniero de CaminosCanales y PuertosUniversitat Politècnica de CatalunyaBarcelonaE-08034Spain. Research Institute of Unconventional Oil and Gas Science and Technology China University of PetroleumBeijing102249China. Department of Oil&Gas Transportation and Engineering Beijing Institute of Petrochemical TechnologyBeijing102617China.

The hydraulic fracturing is a nonlinear,fluid-solid coupling and transient problem,in most cases it is always time-consuming to simulate this process *** recent years,although many numerical methods were proposed to settle this problem,most of them still require a large amount of computer *** it is a high demand to develop more efficient numerical approaches to achieve the real-time monitoring of the fracture geometry during the hydraulic fracturing *** this study,a reduced order modeling technique namely Proper Generalized Decomposition(PGD),is applied to accelerate the simulations of the transient,non-linear coupled system of hydraulic fracturing problem,to match this extremely tight response time *** separability of the solution in space and time dimensions is studied for a simplified model *** solid and fluid equations are coupled explicitly by inverting the solid discrete problem,and a simple iterative procedure to handle the non-linear characteristic of the hydraulic fracturing problem is proposed in this *** validation illustrates that the results of PGD match well with these of standard finite element method in terms o f fracture opening and fluid pressure in the ***,after the off-line calculations,the numerical results can be obtained in real time.

关键词： Hydraulic fracturing proper generalized decomposition reduced order modeling numerical simulation.

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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

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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

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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

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Stress tensors and quantification of fracture patterns to analyze connectivity and potential fluid flow in a mesa landform of the Northern Andes

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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

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