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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.

Pleistocene history of Iberomys,an endangered endemic rodent from southwestern Europe

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Integrative Zoology 2014年第4期9卷 481-497页

作者： Gloria CUENCA-BESCÓS juan manuel LÓPEZ-garcÍA María Angeles GALINDO-PELLICENA Rosa garcÍA-PEREA Julio GISBERT juan ROFES Jacint VENTURA Research Group Aragosaurus-IUCA PaleontologyEarth Sciences DepartmentUniversity of ZaragozaZaragozaSpain Research Group of Paleobiology and Prehistory Human Studies DepartmentUniversity of FerraraFerraraItaly Research Institute of Evolution and Human Behavior UCM-ISCIIIMadridSpain GALEMIA Conservation and Study of Forgotten VertebratesMadridSpain Department of Stratigraphy and Paleontology Faculty of Sciences and TechnologyUniversity of the Basque CountryGipuzkoaGuipúzcoaSpain Department of Animal Biology Plant Biology and EcologyFaculty of BiosciencesUniversity Autonoma de BarcelonaBarcelonaSpain

The extant Cabrera’s vole,Microtus cabrerae,differs in morphology and evolutionary history from the other species of *** arvicoline has unique derived features in the cranium,mandible and ***bly its most conspicuous features are its large size,the high skull in lateral view,the long and distally broad nasals,and the triangle shape of the anteroconid complex,with a marked labio-lingual asymmetry of the occlusal surface of the first lower *** this study,we propose a phylogenetic lineage that includes Cabrera’s vole in what until now has been the Microtus subgenus *** information and several life history traits support the elevation of Iberomys to the rank of *** Iberomys comprises species that have appeared in succession during the Quaternary:in the Early Pleistocene,the extinct *** in the Middle Pleistocene,the extinct *** and in the Late Pleistocene,the extant ***,the extant species shows several biological singularities,such as multiple polymorphic copies of the SRY male-specific gene in both males and females,and the lowest basal metabolic rate in relation to weight among arvicoline ***,its habitat requirement is unique among the Iberian ***,the biological and paleontological data that we present in this work support the elevation of its taxonomic rank to that of ge*** study also suggests a modification of nomenclature:Microtus(Iberomys)brecciensis is replaced with *** and the common name of the extant M.(I.)cabrerae changed from‘topillo’to‘iberon’to improve conservation and protection actions.

关键词： Cabrera’s vole conservation Iberoccitanian endemism Iberomys origin

Models and observations of sunspot penumbrae

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1670-1677页

作者： BORRERO juan manuel Max Planck Institut fr Sonnensystemforschung Max Planck Strasse 2 D 37191 Katlenburg-Lindau Germany

The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the ever-increasing array of observational constraints. In this contribution I will review two of the present models, emphasizing their contributions to this field, but also pinpointing some of their inadequacies to explain a number of recent observations at very high spatial resolution (0.32 ). To help explaining these new observations I propose some modifications to each of those models. These modifications bring those two seemingly opposite models closer together into a general picture that agrees well with recent 3D magneto-hydrodynamic simulations.

关键词： sunspots magnetic fields spectropolarimetry magnetohydrodynamics

All roads go to Salubrinal:endoplasmic reticulum stress,neuroprotection and glial scar formation

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Neural Regeneration Research 2015年第12期10卷 1926-1927页

作者： Lorenzo Romero-Ramírez manuel Nieto-Sampedro M.Asunción Barreda-manso Hospital Nacional de Parapléjicos SESCAM Instituto Cajal CSIC

Central nervous system（CNS）injuries caused by cerebrovascular pathologies（e.g.,stroke）or mechanical contusions（e.g.,traumatic brain injury）disrupt the blood-brain barrier（BBB）that protects the CNS microenviron... 详细信息

关键词： ER CNS TGF

Home range variability and philopatry in Cinereous vultures(Aegypius monachus)breeding in Iberia

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Avian Research 2023年第4期14卷 586-592页

作者： Jorge garcía-Mací Ernesto Alvarez manuel Galan juan Jose Iglesias-Lebrija Marc Galvez Gerard Plana Núria Vallverdú Vicente Urios Grupo de Investigacion Zoología de Vertebrados Universidad de AlicanteApdo.99E-03080AlicanteSpain GREFA(Grupo de Rehabilitacion de la Fauna Autoctonay su Habitat) C/Monte del Pilar S/NE-28220MajadahondaSpain Cos d’Agents Rurals de la Generalitat de Catalunya Spain Associacio Trenca LleidaSpain

Large scavengers are strongly dependent on environmental conditions and carrion distribution and abundance,so season and breeding-related factors may influence the spatial ecology of species such as the Cinereous Vulture(Aegypius monachus),the largest European *** holds one of the biggest populations worldwide,but some aspects of the spatial ecology of the species in this region remain *** this study,17 adult Cinereous Vultures were GPS-tracked in order to study their spatial ecology during the adult *** average monthly home ranges(95%Kernel Density Estimation,KDE)and core areas(50%KDE)were 6543±19,935 km^(2)and 1174±4004 km^(2),*** average monthly home range fidelity ranged between 50 and 73%.Differences in movement-related variables between the seasonal periods(incubation,chick-rearing and non-breeding)were *** the chick-rearing period,the monthly accumulated distance was higher than during the other periods:3316±1108(chick-rearing)vs.1621±622(incubation)vs.1726±1159 km per month(nonbreeding).Additionally,large home range sizes were more frequent during the chick-rearing *** are two likely causes for these seasonal ***,chick-rearing entails a higher energetic expenditure by the parental individuals in foraging activities,so larger movements and foraging areas are expected during this ***,the flight is favoured during spring and summer due to environmental *** chick-rearing and warm months is a great evolutionary advantage for soaring-gliding raptors,as it allows them to cover larger areas with low energy ***,six individuals tagged as nestlings highlight the philopatric behaviour of the species:vultures settle their breeding areas 54±51 km from their natal nest(range=9–138 km).

关键词： Bird of prey Movement ecology Philopatry Raptor Scavenger

Pre-fire aboveground biomass, estimated from LiDAR, spectral and field inventory data, as a major driver of burn severity in maritime pine (Pinus pinaster) ecosystems

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Forest Ecosystems 2022年第2期9卷 234-246页

作者： Jose manuel Fernandez-Guisuraga Susana Suarez-Seoane Paulo MFernandes Victor Fernandez-garcia Alfonso Fernandez-manso Carmen Quintano Leonor Calvo Area of Ecology Department of Biodiversity and Environmental ManagementFaculty of Biological and Environmental SciencesUniversity of Leon24071LeonSpain Centro de Investigacao e de Tecnologias Agroambientais e Biologicas Universidade de Tras-os-Montes e Alto Douro5000-801Vila RealPortugal Department of Organisms and Systems Biology(Ecology Unit)and Research Unit of Biodiversity(IMIB UO-CSIC-PA)University of OviedoOviedoMieresSpain Agrarian Science and Engineering Department School of Agricultural and Forestry EngineeringUniversity of Leon24400PonferradaSpain Electronic Technology Department School of Industrial EngineeringUniversity of Valladolid47011ValladolidSpain Sustainable Forest Management Research Institute University of Valladolid-Spanish National Institute for Agriculture and Food Research and Technology(INIA)34004PalenciaSpain

Background:The characterization of surface and canopy fuel loadings in fire-prone pine ecosystems is critical for understanding fire behavior and anticipating the most harmful ecological effects of ***,the joint consideration of both overstory and understory strata in burn severity assessments is often *** aim of this work was to assess the role of total,overstory and understory pre-fire aboveground biomass(AGB),estimated by means of airborne Light Detection and Ranging(LiDAR)and Landsat data,as drivers of burn severity in a megafire occurred in a pine ecosystem dominated by Pinus pinaster *** the western Mediterranean ***:Total and overstory AGB were more accurately estimated(R^(2) equal to 0.72 and 0.68,respectively)from LiDAR and spectral data than understory AGB(R^(2)=0.26).Density and height percentile LiDAR metrics for several strata were found to be important predictors of *** severity responded markedly and non-linearly to total(R^(2)=0.60)and overstory(R ^(2)=0.53)AGB,whereas the relationship with understory AGB was weaker(R ^(2)=0.21).Nevertheless,the overstory plus understory AGB contribution led to the highest ability to predict burn severity(RMSE=122.46 in dNBR scale),instead of the joint consideration as total AGB(RMSE=158.41).Conclusions:This study novelty evaluated the potential of pre-fire AGB,as a vegetation biophysical property derived from LiDAR,spectral and field plot inventory data,for predicting burn severity,separating the contri-bution of the fuel loads in the understory and overstory strata in Pinus pinaster *** evidenced relationships between burn severity and pre-fire AGB distribution in Pinus pinaster stands would allow the implementation of threshold criteria to support decision making in fuel treatments designed to minimize crown fire hazard.

关键词： Aboveground biomass Burn severity Landsat LiDAR Pinus pinaster

Preparation and Characterization of Flexible, Transparent and Thermally Stable Aromatic Co-polyamides

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Chinese Journal of Polymer Science 2019年第2期37卷 136-141页

作者： José Antonio Tec-Sánchez Andrés Iván Oliva Arias manuel Aguilar-Vega juan Valerio Cauich-Rodríguez José Luis Santiago-garcía Unidad de Materiales Centro de Investigación Científica de Yucatán A. C. Centro de Investigación y de Estudios Avanzados del IPN Unidad Mérida Departamento de Física Aplicada

Two aromatic co-polyamides were synthesized combining two diacid monomers containing bulky pendant groups, 5-(9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)isophthalic acid(DEAIA) and 5-tert-butylisophthalic acid(TERT), with 4,4′-(hexafluoroisopropylidene)dianiline(HFA) or 2,3,5,6-tetramethyl-1,4-phenylenediamine(Durene) by direct polycondensation. The structures of the obtained aromatic co-polyamides were confirmed by FTIR, Raman and 1 H-NMR. The co-copolyamide films, DHTH and DDTD, exhibited rms-roughness values between 0.94 and 1.60 nm, respectively. Moreover, they presented good thermal stability up to300 °C. Young's moduli of the co-polyamide films were between 4.1 and 4.3 GPa. X-ray diffraction results showed that the co-polyamide films were amorphous due to the incorporation of both bulky pendant groups, tert-butyl and dibenzobarrelene. The combination of bulky pendant groups provided intrinsically transparent co-polyamide films with a transmittance higher than 88% in the range of 400-780 *** to these outstanding film and optical properties, they are suggested to be flexible substrates in applications for solar cell and other portable electronic devices.

关键词： Co-polyamides Flexible films Transmittance Thermal stability Polycondensation

Virtual Conductance Based Cascade Voltage Controller for VSCs in Islanded Operation Mode

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1704-1713页

作者： Francisco Jesús Matas-Díaz manuel Barragán-Villarejo juan Carlos Olives-Camps juan manuel Mauricio JoséMaría Maza-Ortega Department of Elec‐trical Engineering Universidad de SevillaSeville 41092Spain

Voltage source converters have become the main enabler for the integration of distributed energy resources in *** the case of islanded operation,these devices normally set the amplitude and frequency of the network voltage by means of a cascade controller composed of an outer voltage control loop and an inner current control *** strategies to compute the gains of both control loops have been proposed in the literature in order to obtain a fast and decoupled response of the voltages at the point of common *** paper proposes an alternative and simple methodology based on the introduction of a virtual conductance in the classic cascade *** strategy allows to design each control loop independently,obtaining a closed-loop response of a first-order *** this way,the gains of each control loop are easily derived from the parameters of the LC coupling filter and the desired closed-loop time ***,a state observer is included in the controller to estimate the inductor current of the LC filter in order to reduce the number of required measurements.A laboratory testbed is used to validate and compare the proposed *** experimental results demonstrate the effectiveness of the proposal both in steady-state and transient regimes.

关键词： Voltage source converter microgrid cascade controller virtual conductance

Hot corrosion mechanism of yttria-stabilized zirconia powder in the presence of molten Na_(2)SO_(4)+V_(2)O_(5) salts

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Rare Metals 2021年第5期40卷 1307-1316页

作者： Jhonattan De la Roche juan manuel Alvarado-Orozco Alejandro Toro Tribology and Surfaces Group Universidad Nacional de ColombiaMedellin 050041Colombia Centro de Ingeniena y Desarrollo Industrial-CIDESI Queretaro 76125Mexico Consorcio de Manufactura Aditiva-CONMAD Queretaro 76125Mexico

The hot corrosion behavior of yttria-stabilized zirconia(YSZ)powder specimens exposed to Na_(2)SO_(4)/V_(2)O_(5) salts mixtures at high temperature was *** tests were carried out at 1000℃ for 10 h,the salt concentrations varied from 0.1 wt%to 1.00 wt%,and the Na_(2)SO_(4)/V_(2)O_(5) mass ratios were between 0.20 and 0.44 following a factorial design 22.X-ray diffraction(XRD)analyses of the tested samples showed with a confidence of95%that the mixture composed of 32 wt%Na_(2)SO_(4)+68 wt%V_(2)O_(5),and 1.00 wt% salt concentration led to high destabilization of the t’-YSZ phase and formation of YVO_(4) products.A second set of experiments were conducted to assess the influence of temperature on the hot corrosion response of the YSZ in the range between 490 and 1100℃.Thermogravimetric analysis(TGA)experiments and Rietveld adjustments of XRD patterns showed that the mass loss of the samples varied with testing temperature and also that the major destabilization of tetragonal phase occurred at 900℃.

关键词： Hot corrosion Molten salts Yttria-stabilized zirconia Thermal barrier coatings