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

林业研究:英文版 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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Synthesis of advanced ceramics by hydrothermal crystallization and modified related methods

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Journal of Advanced ceramics 2012年第3期1卷 204-220页

作者： JoséORTIZ-LAnDEROS c.rlos GÓMEZ-YÁÑEZ Rigoberto LÓPEZ-JUÁREZ iván DÁVALOS-VELAScO Heriberto PFEIFFER Departamento de Ingeniería Metalúrgica Escuela Superior de Ingeniería Química e Industrias ExtractivasIPNUPALMAv.Instituto Politécnico Nacional s/nCP 07738México DFMéxico. centro de ciencias Aplicadas y Desarrollo Tecnológico Universidad Nacional Autónoma de MéxicoA.P.70-186CoyoacánMéxico D.F.México. Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCircuito exterior s/nCiudad UniversitariaDel.CoyoacánCP 04510México DFMéxico.

The present article aims to give a brief overview about the advantages of the hydrothermal crystallization method for the synthesis of advanced *** is given,not only on the conventional hydrothermal crystallization,but also on some of its variants;such as ultrasound-assisted,electrochemical-assisted,microwave-assisted and surfactant-assisted hydrothermal methods which open up new opportunities for the synthesis of ceramic materials with novel properties demanded for advanced *** the current work the synthesis of barium titanate(BaTiO3),lithium metasilicate(Li2SiO3)and sodium-potassium niobate(na,K)nbO3 powders are reported as cases of study.

关键词： hydrothermal synthesis barium titanate Li_(2)SiO_(3) potassium-sodium niobate

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Fast global kernel fuzzy c-means clustering algorithm for consonant/vowel segmentation of speech signal

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Journal of Zhejiang University-Science c(computers and Electronics) 2014年第7期15卷 551-563页

作者： Xian ZAnG Felipe P. VISTA iv Kil To cHOnG Department of Electronic Engineering Jeonbuk National University Advanced Electronics and Information Research center Jeonbuk National University

We propose a novel clustering algorithm using fast global kernel fuzzy c-means-F(FGKFcM-F), where F refers to kernelized feature space. This algorithm proceeds in an incremental way to derive the near-optimal solution by solving all intermediate problems using kernel-based fuzzy c-means-F(KFcM-F) as a local search procedure. Due to the incremental nature and the nonlinear properties inherited from KFcM-F, this algorithm overcomes the two shortcomings of fuzzy c-means(FcM): sen- sitivity to initialization and inability to use nonlinear separable data. An accelerating scheme is developed to reduce the compu-tational complexity without significantly affecting the solution quality. Experiments are carried out to test the proposed algorithm on a nonlinear artificial dataset and a real-world dataset of speech signals for consonant/vowel segmentation. Simulation results demonstrate the effectiveness of the proposed algorithm in improving clustering performance on both types of datasets.

关键词： Fuzzy c-means clustering Kernel method Global optimization consonant/vowel segmentation

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25-hydroxycholecalciferol reverses heat induced alterations in bone quality in finisher broilers associated with effects on intestinal integrity and inflammation

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Journal of Animal Science and Biotechnology 2022年第2期13卷 499-519页

作者： Huaiyong Zhang Maryam Majdeddin Djoere Gaublomme Bernard Taminiau Matthieu Boone Dirk Elewaut George Daube iván Josipovic Keying Zhang Joris Michiels Laboratory for Animal nutrition and Animal Product Quality Department of Animal Sciences and Aquatic EcologyGhent University9000 GhentBelgium Key laboratory of Animal Disease-resistant nutrition Ministry of EducationInstitute of Animal NutritionSichuan Agricultural UniversityYa’an 611130SichuanChina Unit Molecular Immunology and Inflammation VIB Center for Inflammation ResearchGhent University and Department of RheumatologyGhent University Hospital9000 GhentBelgium Department of Food Sciences-Microbiology University of Liège4000 LiègeBelgium Ghent University centre for X-ray Tomography(UGcT) Ghent University9000 GhentBelgium Department of Physics and Astronomy Radiation Physics Research GroupGhent University9000 GhentBelgium

Background:Alterations in ambient temperature have been associated with multiple detrimental effects on broilers such as intestinal barrier disruption and dysbiosis resulting in systemic *** and 25-hydroxycholecalciferol(25-OH-D_(3))have shown to play a negative and positive role,respectively,in the regulation of bone *** the potential of 25-OH-D_(3)in alleviating heat induced bone alterations and its mechanisms was ***:Heat stress(HS)directly induced a decrease in tibia material properties and bone mass,as demonstrated by lower mineral content,and HS caused a notable increase in intestinal *** with dietary 25-OH-D_(3)reversed the HS-induced bone loss and barrier *** suffering from HS exhibited dysbiosis and increased expression of inflammatory cytokines in the ileum and bone marrow,as well as increased osteoclast number and *** changes were prevented by dietary 25-OH-D_(3)***,dietary 25-OH-D_(3)addition decreased abundance of B-and T-cells in blood,and the expression of inflammatory cytokines,especially TnF-α,in both the ileum and bone marrow,but did not alter the diversity and population or composition of major bacterial *** regard to bone remodeling,dietary 25-OH-D_(3)supplementation was linked to a decrease in serum c-terminal cross-linked telopeptide of type I collagen reflecting bone resorption and a concomitant decrement in osteoclast-specific marker genes expression(*** K),whereas it did not apparently change serum bone formation markers during ***:These data underscore the damage of HS to intestinal integrity and bone health,as well as that dietary 25-OH-D_(3)supplementation was identified as a potential therapy for preventing these adverse effects.

关键词： Bone remodeling HS Inflammation Intestinal barrier Tibial mass

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Dragon Tails:convergent caudal Morphology in Winged Archosaurs

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Acta Geologica Sinica(English Edition) 2012年第6期86卷 1402-1412页

作者： W.Scott PERSOnS iv Philip J.cURRIE Department of Biological Sciences University of Alberta Department of Biological Sciences CW 405 Biological Sciences Bldg.University of Alberta

In the tails of dromaeosaurid dinosaurs and rhamphorhynchid pterosaurs, elongate osteological rods extend anteriorly from the chevrons and the prezygapophyses. These caudal rods are positioned in parallel and are stacked dorsoventrally. The fully articulated and three-dimensionally preserved caudal series of some dromaeosaurid specimens show that individually these caudal rods were flexible, not rigid as previously thought. However, examination of the arrangement of the caudal rods in cross-section indicates that the combined effect of multiple caudal rods did provide substantial rigidity in the dorsoventral, but not in the lateral, plane. The results of digital muscle reconstructions confirm that dromaeosaurids and rhamphorhynchids also shared greatly reduced caudofemoral muscles in the anterior tail region. The striking similarities between the tails of dromaeosaurids and rhamphorhynchids suggest that both evolved under similar behavioral and biomechanical pressures. combined with recent discoveries of primitive deinonychosaurs that phylogenetically bracket the evolution of dromaeosaurid caudal rods between two arboreal gliding/flying forms, these results are evidence that the unique caudal morphologies of dromaeosaurids and rhamphorhynchids were both adaptations for an aerial lifestyle.

关键词： caudal musculature convergent evolution dinosaurs dromaeosaurids functionalmorphology pterosaurs rhamphorhynchids

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Fagus sylvatica and Quercus pyrenaica:Two neighbors with few things in common

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Forest Ecosystems 2023年第2期10卷 162-175页

作者： Sergio de Tomás Marín Jesús Rodríguez-calcerrada Salvador Arenas-castro iván Prieto Guillermo González Luis Gil Enrique G.de la Riva Department of Ecology Brandenburgische Technische Universität Cottbus-SenftenbergKonrad-Wachsmann-Allee 603046CottbusGermany Forest Genetics and Ecophysiology Research Group School of Forestry EngineeringUniversidad Politécnica de MadridMadridSpain Area of Ecology Botany DepartmentEcology and Plant PhysiologyFaculty of SciencesUniversidad de CórdobaCórdobaSpain Ecology Department Faculty of Biology and Environmental SciencesUniversidad de LeónLeónSpain

Background:The Iberian Peninsula comprises one of the largest boundaries between Mediterranean and Eurosiberian vegetation,known as sub-Mediterranean *** ecotone hosts many unique plant species and communities and constitutes the low-latitude(warm)margin of numerous central European species which co-occur with Mediterranean *** of the main species found in this region are the Eurosiberian European beech(Fagus sylvatica L.)and the Mediterranean Pyrenean oak(Quercus pyrenaica Willd.).It remains unclear how the different physiological and adaptive strategies of these two species reflect their niche partitioning within a subMediterranean community and to what extent phenotypic variation(intraspecific variability)is driving niche partitioning across Eurosiberian and Mediterranean ***:We quantified functional niche partitioning,based on the n-dimensional hypervolume to nine traits related to resource acquisition strategies(leaf,stem and root)plus relative growth rate as an additional wholeplant trait,and the environmental niche similarity between Pyrenean oak and European ***,we analyzed the degree of phenotypic variation of both target species and its relationship with relative growth rates(RGR)and environmental *** recruitment was measured for both target species as a proxy for the average ***:Species’functional space was highly segregated(13.09%overlap),mainly due to differences in niche breadth(59.7%)rather than niche replacement(25.6%),and beech showed higher trait variability,i.e.,had larger functional ***,both species shared the environmental space,i.e.,environmental niches were *** plant traits were not related to abiotic variables or RGR,neither did RGR to plant ***:Both target species share similar environmental space,however,show notably different functional resource-use strategies,promoting a high complementarity that contributes to maintaining a high functiona

关键词： Environmental niche European beech Forest dynamics Functional niche Hypervolume Pyrenean oak Species coexistence Sub-Mediterranean community

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Distribution of algae and cyanobacteria of biological soil crusts along the elevation gradient in mountain plant communities at the northern Urals(Russian European northeast)

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Journal of Mountain Science 2022年第3期19卷 637-646页

作者： iv nOVAKOVSKAYA En PATOVA YA DUBROVSKIY AB nOVAKOVSKIY EE KULYUGInA Institute of Biology Komi Scientific CentreUral BranchRussian Academy of SciencesKommunisticheskaya st.28SyktyvkarKomi Republic167982Russia

This paper describes the biodiversity of cyanobacteria and microalgae of biological soil crusts(BSc)on bare substrates in different mountain vegetation types at the northern *** total,we identified 99 algal species from six divisions in all sampled *** species diversity and structure of BSc algal communities show a relationship with environmental factors(altitude,soil p H and humidity,and illumination).Taxonomic diversity of algae decreases along the altitude gradient from mountain meadow to mountain *** and cyanobacteria species from six divisions were identified in meadow communities,five in mountain forests and four in mountain *** observed a positive correlation between species diversity of phototrophic microorganisms and altitude in the forest communities,but a negative correlation in the *** dominant complex of cyanobacterial and algal species in BSc was specific for each type of plant community and was reflective of the habitat *** species diversity and morphological organization of the BSc algae thalli can be used as a criterion for the ongoing assessment of climatic changes in high latitudes and mountain regions.

关键词： Biological soil crusts cyanobacteria and microalgae Altitude gradient northern Urals

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The Difficult Airway: A new Simplified Approach to an Old complex Problem

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Open Journal of Anesthesiology 2017年第8期7卷 210-233页

作者： iván Mauricio Alvarado Arteaga Department of Anesthesiology Hospital de San Jose Bogotá Colombia

Difficult airway situations are a major cause of morbidity, mortality and malpractice claims in anesthetic practice and other critical care settings. Although infrequent, they are serious and complex situations where many variables interact. Among these variables, quick and accurate rescuer decision-making is a major outcome determinant. Emerging evidence, recent advances in technology and development of new devices have provided new tools to deal with the problem, but still, basic underlying principles of management remain. Based on the available evidence and expert consensus, multiple guidelines and algorithms have been published, but they may have limited applicability, contain confusing and ambiguous recommendations or address very specific clinical situations. This narrative review attempts to summarize, organize and consolidate current trends and supported recommendations of the updated guidelines in one practical, concise and unified guide, proposing a simple, intuitive and novel algorithm.

关键词： Anesthesia Airway Management Airway Obstruction Intubation-Intratracheal Pulmonary Ventilation Guideline Algorithms

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Glial cells in the center of future ischemic stroke treatments

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neural Regeneration Research 2022年第12期17卷 2659-2660页

作者： ivóH.Hernández Maria JoséPérez-Álvarez Genomic Instability Group Spanish National Cancer Research Centre(CNIO)MadridSpain Departamento de Biología(Fisiología Animal)Facultad de ciencias Universidad Autónoma de Madridand Instituto de Biología Molecular-CBMSOUAM/CSICMadridSpain

In the last century,increasing knowledge about glial cells has revealed their importance in brain physiology and disease and an exciting potential target for new therapeutic interventions(Hernández et al.,2021).Ischemic stroke is the most common of all types of *** the second leading cause of disability and mortality,ischemic stroke is a serious socio-economic burden *** it has been strongly associated with aging,during 2020 cOVID-19 emerged as a new risk factor for ischemic stroke in younger patients(cagnazzo et al.,2021).The only therapy or intervention currently available for humans is early reperfusion after the onset of the first ***,due to the high risk of brain hemorrhage,these treatments are suitable for only a small percentage of ***,reperfusion does not prevent post-injury neurodegeneration,hence the importance of finding new therapeutic alternatives to ameliorate ischemic damage and improve post-stroke quality of life.

关键词： mortality treatment younger

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coherent OnU based on 850 μm-long cavity-RSOA for next-generation ultra-dense access network

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chinese Optics Letters 2016年第5期14卷 19-23页

作者： Guang Yong chu Adolfo Lerín iván n.cano Victor Polo Josep Prat Department of Signal Theory and communications Universitat Politècnica de Catalunya

In this Letter, an efficient bidirectional differential phase-shift keying （DPSK）--DPSK transmission for a ultra- dense wavelength division-multiplexed passive optical network is proposed. A single distributed feedback laser at the optical network unit （OnU） is used both as the local laser for downlink coherent detection and the optical carrier for uplink. Phase-shift keying is generated using a low-cost reflective semiconductor optical amplifier （RSOA） at the OnU. The RSOA chip has the bandwidth of 4.7 GHz at the maximum input power and bias current. For uplink transmission, the sensitivity of the RSOA chip reaches -48.2 dBm at the level of bit error rate = 10^-3 for back-to-back, and the penalty for 50 km transmission is less than 1 dB when using polarization diversity.

关键词： OnU RSOA coherent OnU based on 850 m-long cavity-RSOA for next-generation ultra-dense access network

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