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Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual juan guerra-hernández Cristóbal Ordóñez Tiago de Conto Felipe Bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

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Using GEDI lidar data and airborne laser scanning to assess height growth dynamics in fast-growing species:a showcase in Spain

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Forest Ecosystems 2021年第1期8卷 182-198页

作者： juan guerra-hernández Adrián Pascual 3edata Centro de iniciativas empresariaisFundación CEL.O Palomar s/n27004 LugoSpain Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349-017 LisbonPortugal Center for Global Discovery and Conservation Science Arizona State UniversityHiloHA 96720USA

Background:The NASA’s Global Ecosystem Dynamics Investigation(GEDI)satellite mission aims at scanning forest ecosystems on a multi-temporal short-rotation *** GEDI data can validate and update statistics from nationwide airborne laser scanning(ALS).We present a case in the Northwest of Spain using GEDI statistics and nationwide ALS surveys to estimate forest dynamics in three fast-growing forest ecosystems comprising 211,346 *** objectives were:i)to analyze the potential of GEDI to detect disturbances,ii)to investigate uncertainty source regarding non-positive height increments from the 2015–2017 ALS data to the 2019 GEDI laser shots and iii)to estimate height growth using polygons from the Forest Map of Spain(FMS).A set of 258 National Forest Inventory plots were used to validate the observed height ***:The spatio-temporal assessment from ALS surveying to GEDI scanning allowed the large-scale detection of *** mean annual height growths were 0.79(SD=0.63),0.60(SD=0.42)and 0.94(SD=0.75)m for Pinus pinaster,Pinus radiata and Eucalyptus spp.,*** median annual values from the ALS-GEDI positive increments were close to NFI-based growth values computed for Pinus pinaster and Pinus radiata,*** effect of edge border,spatial co-registration of GEDI shots and the influence of forest cover in the observed dynamics were important factors to considering when processing ALS data and GEDI ***:The use of GEDI laser data provides valuable insights for forest industry operations especially when accounting for fast ***,errors derived from positioning,ground finder and canopy structure can introduce uncertainty to understand the detected growth patterns as documented in this *** analysis of forest growth using ALS and GEDI would benefit from the generalization of common rules and data processing schemes as the GEDI mission is increasingly being utilized in the forest remote sensing community.

关键词： Forest inventory Productivity Multi-temporal LiDAR Full-waveform(FW) Satellite mapping

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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

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Latest developments in early diagnosis and specific treatment of severe influenza infection

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Journal of Intensive Medicine 2024年第2期4卷 160-174页

作者： Francisco Valenzuela-Sánchez Blanca Valenzuela-Méndez juan Francisco Rodríguez-Gutiérrez Ángel Estella Intensive Care Unit University Hospital of JerezRonda de Circunvalación s/nJerez de la FronteraSpain Haematology Department University Hospital of JerezRonda de Circunvalación s/nJerez de la FronteraSpain Centro de Investigación Biomédica en Red Enfermedades respiratoriasCIBERESInstituto de Salud Carlos IIIAv.de Monforte de LemosMadridSpain Department of Oncological Surgery Institut du Cancer de Montpellier(ICM)Parc Euromédecine208 Av.des ApothicairesMontpellierFrance Department of Medicine Faculty of MedicineUniversity of CádizCalle Doctor MarañónCádizSpain Instituto de Investigación e Innovación Biomédica de Cádiz(INIBiCA) Avenida Ana de Viya 21CádizSpain

Influenza pandemics are unpredictable recurrent events with global health,economic,and social *** objective of this review is to provide an update on the latest developments in early diagnosis and specific treatment of the disease and its complications,particularly with regard to respiratory organ *** advances in treatment,the rate of mortality in the intensive care unit remains approximately 30%.Therefore,early identification of potentially severe viral pneumonia is extremely important to optimize treatment in these *** pathogenesis of influenza virus infection depends on viral virulence and host ***,in some patients,it is associated with an excessive systemic response mediated by an authentic cytokine *** process leads to severe primary pneumonia and acute respiratory distress *** prognostication in the emergency department based on comorbidities,vital signs,and biomarkers(e.g.,procalcitonin,ferritin,human leukocyte antigen-DR,mid-regional proadrenomedullin,and lactate)is *** of these biomarkers on admission may facilitate clinical decision-making to determine early admission to the hospital or the intensive care *** decisions are reached considering pathophysiological circumstances that are associated with a poor prognosis(e.g.,bacterial co-infection,hyperinflammation,immune paralysis,severe endothelial damage,organ dysfunction,and septic shock).Moreover,early implementation is important to increase treatment *** on a limited level of evidence,all current guidelines recommend using oseltamivir in this *** possibility of drug resistance should also be *** options include other antiviral drugs and combination therapies with monoclonal ***,it is not recommended to use corticosteroids in the initial treatment of these ***,the implementation of supportive measures for respiratory failure is ***

关键词： Influenza Pandemic Respiratory failure Acute respiratory distress syndrome Intensive care unit admission

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Rainfall Sensitivity to Microphysics and Planetary Boundary Layer Parameterizations in Convection-Permitting Simulations over Northwestern South America

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Journal of Meteorological Research 2024年第4期38卷 805-825页

作者： K.Santiago hernAndez Sebastian GOMEZ-RIOS juan J.HENAO Vanessa ROBLEDO Alvaro RAMiREZ-CARDONA Angela M.RENDON Geolimna Escuela AmbientalFacultad de IngenieriaUniversidad de AntioquiaMedellin 050010Colombia Grupo de Ingenieria y Gestion Ambiental(GIGA) Escuela AmbientalFacultad de IngenieriaUniversidad de AntioquiaMedellin 050010Colombia Division of Atmospheric Sciences Desert Research InstituteRenoNV 89512USA

Convection-permitting modeling allows us to understand mechanisms that influence rainfall in specific ***,microphysics parameterization(MP) and planetary boundary layer(PBL) schemes remain an important source of uncertainty,affecting rainfall intensity,occurrence,duration,and ***,we study the sensitivity of rainfall to three MP [Weather Research and Forecasting(WRF) Single-Moment 6-class(WSM6),Thompson,and Morrison] and two PBL [the Yonsei University(YSU) and Mellor–Yamada Nakanishi Niino(MYNN)] schemes with a convection-permitting resolution(4 km) over northwestern South America(NWSA).Simulations were performed by using the WRF model and the results were evaluated against soundings,rain gauges,and satellite data,considering the spatio-temporal variability of rainfall over diverse regions prone to deep convection in *** and PBL schemes largely influenced simulated rainfall,with better results for the less computationally expensive WSM6 MP and YSU PBL *** rain gauges and satellite estimates,simulations with Morrison MP overestimated rainfall,especially westward of the Andes,whereas the MYNN PBL underestimated precipitation in the Amazon–Savannas *** found that the uncertainty in the rainfall representation is highly dependent on the region,with a higher influence of MP in the Colombian Pacific and PBL in the Amazon–Savannas *** analyzing rainfall-related processes,the selection of both MP and PBL parameterizations exerted a large influence on the simulated lower tropospheric moisture flux and moisture *** schemes significantly influenced the downward shortwave radiation,with MYNN simulating a greater amount of low clouds,which decreased the radiation ***,latent heat fluxes were greater for YSU,favoring moist convection and *** schemes had a marked impact on vertical ***,Morrison MP showed stronger convection and higher precipitation rates,which is assoc

关键词： sensitivity microphysics planetary boundary layer(PBL) Weather Research and Forecasting(WRF) processes

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Portal vein arterialization in 25 liver transplant recipients:A Latin American single-center experience

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World Journal of Transplantation 2024年第2期14卷 135-147页

作者： Nicolas Andres Cortes-Mejia Diana Fernanda Bejarano-Ramirez juan Jose guerra-Londono Diego Rymel Trivino-Alvarez Raquel Tabares-Mesa Alonso Vera-Torres Division of Anesthesiology Critical Care Medicineand Pain MedicineThe University of Texas MD Anderson Cancer CenterHoustonTX 77030United States Transplant and Hepatobiliary Surgery Department Fundacion Santa Fe de BogotaBogota 110111Colombia General Surgery Department Fundacion Santa Fe de BogotaBogota 110111Colombia

BACKGROUND Portal vein arterialization(PVA)has been used in liver transplantation(LT)to maximize oxygen delivery when arterial circulation is compromised or has been used as an alternative reperfusion technique for complex portal vein thrombosis(PVT).The effect of PVA on portal perfusion and primary graft dysfunction(PGD)has not been *** patients receiving PVA and LT at the Fundacion Santa Fe de Bogota between 2011 and 2022 were *** account for the time-sensitive effects of graft perfusion,patients were classified into two groups:prereperfusion(pre-PVA),if the arterioportal anastomosis was performed before graft revascularization,and postreperfusion(post-PVA),if PVA was performed *** pre-PVA rationale contemplated poor portal hemodynamics,severe vascular steal,or ***-PVA was considered if graft hypoperfusion became *** interventions were attempted before PVA.

关键词： Liver transplantation Portal vein arterialization Arteriovenous anastomoses Portal hypertension Portal vein thrombosis Spontaneous portosystemic shunts Vascular steal phenomenon Primary graft dysfunction Early allograft dysfunction

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Prognostic Factors for Mortality in Severe Traumatic Brain Injury at HGZ 46, Villahermosa, Tabasco, Period from March 1, 2021 to December 31, 2022

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Open Journal of Emergency Medicine 2024年第1期12卷 1-9页

作者： América del Carmen Flores Jiménez Eduardo Guillermo Aguilar López Rafael Blanco De La Vega Pérez juan Manuel hernández Vázquez Emergency Room at General Zone Hospital #46 (HGZ46) “Dr. Bartolomé Reynés Berezaluce” from Mexican Institute of Social Security Tabasco Mexico Intensive Care Unit at General Zone Hospital #46 (HGZ46) “Dr. Bartolomé Reynés Berezaluce” from Mexican Institute of Social Security Tabasco Mexico

Introduction: A traumatic brain injury (TBI) is caused by a forceful bump, blow, or jolt to the head or body, or by an object that pierces the skull and interrupts the normal function of the brain. Severe TBI is estimated at 73 cases per 100,000 people. The mortality of severe TBI can be reduced if a timely diagnosis and treatment of the injuries are made through prognostic factors. Objective: To determine the prognostic factors related to mortality in severe traumatic brain injury at the Hospital General de Zona No. 46. Material and Methods: Retrospective, cross-sectional and descriptive study in beneficiaries admitted to the Hospital General de Zona (HGZ) No. 46 of the Mexican Institute of Social Security (IMSS by its acronym in Spanish), with a diagnosis of severe TBI;the possible prognostic factors related to mortality of severe TBI were obtained from their records. Measures of central tendency and chi square were used for data analysis. Results: The study sample consisted of 60 subjects diagnosed with severe traumatic brain injury, of which 5 (8%) were women and 55 (92%) were men, and all 60 (100%) patients died. The average age of the sample was 26 with a standard deviation of 9 years. The variables that had a p value less than or equal to 0.05 were: Mydriasis, seizures, Hyperglycemia, Normoglycemia, Hypothermia and Hypotension. This means that these variables were associated with mortality. Conclusion: Statistical significance is demonstrated in prognostic factors of mortality in severe traumatic brain injury with p < 0.05 in the case of mydriasis, seizures, hyperglycemia, normoglycemia, hypothermia and hypotension.

关键词： Traumatic Brain Injury Prognostic Factors Mortality Severity

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Quality assessment of the Topo-Iberia CGPS stations and data quality's effects on postfit ionosphere-free phase residuals

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Geodesy and Geodynamics 2024年第2期15卷 189-199页

作者： juan A.García-Armenteros Center for Advanced Studies in Earth Sciences Energy and Environment(CEACTEMA)University of Jaén23071 JaenSpain

This paper analyzed GPS data from the Topo-Iberia network spanning almost 12 years(2008-2020).The data quality information for all 26 Topo-Iberia stations is provided for the first time,complementing the Spanish Geological Survey’s storage *** analyses based on quality indicators obtained using TEQC have been carried *** guidelines and data quality information from the IGS stations have been considered as the quality references,with the stations ALJI,EPCU,and TIOU standing out as the worst stations,while on the contrary,FUEN,PALM,PILA,and TRIA meet the quality requirements to become an IGS *** relationship between the GPS data quality and their GAMIT-and Gipsy X-derived postfit ionosphere-free phase residuals has also been investigated,and the results reveal an inversely proportional *** has been found that the stations showing an increase in elevation of the horizon line,also show an increase in cycle slips and multipath,are among the poorest quality stations,and among those with the highest postfit RMS of phase ***,the evolution of the vegetation around the antenna should be considered as it could cause a progressive loss of quality,which is not complying with the IGS *** quality assessment shows that the Topo-Iberia stations are appropriate for geodetic purposes,but permanent monitoring would be necessary to avoid the least possible loss of data and *** addition,a method to characterize the GNSS data quality is proposed.

关键词： GPS dataquality's effects IGS quality standard Postfit LC phase residual Qualityassessment Topo-Iberia CGPS network

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Thermodynamic property of sandwich cylindrical shell structure with metallic wire mesh:Numerical modeling and experimental analysis

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Chinese Journal of Aeronautics 2024年第1期37卷 138-152页

作者： Xin XUE Guojian SHEN juan LIAO Institute of Metal Rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China Fujian Shuikou Power Generation Group Co. LTDFuzhou 350000China

As a new addition to lightweight composite structures,the sandwich cylindrical shell with a metallic wire mesh core has emerged as a promising solution for thermodynamic performance analysis at elevated *** intricate interwoven cellular formations within the metallic wire mesh pose difficulties for thermo-mechanical modeling and property ***,the constitutive models employed to characterize hysteresis phenomena were presented,comprising isotropic elasticity,Bergstrom-Boyce model,Ogden hyper-elasticity,and parameter identification through mechanical examinations at varying ***,the finite element modeling of cylindrical shell structures was determined for modal and steady-state dynamic ***,the experimental procedures were carried out,including the preparation of the sandwich cylindrical shell and the dynamic testing *** first-order natural frequency of the cylindrical shell structure is close to the resonance frequency of the dynamic test results,with a maximum error of 6.5%,demonstrating the accuracy of the simulation *** compared to the solid-core cylindrical shell,the average insertion loss of the sandwich cylindrical shell structure within the frequency range of 10–1000 Hz at room temperature is up to 11.09 ***,at elevated temperatures,the average insertion loss of the sandwich cylindrical shell decreases but fluctuates as the temperature changes.

关键词： Energy dissipation Metallic matrix composites Numerical analysis Sandwich structure Thermodynamic properties

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Interface property of dissimilar Ti-6Al-4V/AA1050 composite laminate made by non-equal channel lateral co-extrusion and heat treatment

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Defence Technology（防务技术） 2024年第3期33卷 197-208页

作者： juan Liao Mengmeng Tian Xin Xue School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China

The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel lateral co-extrusion *** microstructural evolution and growth mechanism in the diffusion layer were discussed further to optimize the bonding quality by appropriately adjusting process *** electron microscopes(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)were used to characterize interfacial diffusion *** shear test was used to determine the mechanical properties of the interfacial diffusion *** experimental results indicate that it is possible to co-extrusion Ti-6Al-4V/AA1050 compound profiles using non-equal channel lateral *** heat treatment processes affect the thickness of the diffusion *** the temperature and time of heat treatment increase,the thickness of the reaction layers increases ***,the shear strength of the Ti-6Al-4V/AA1050 composite interface is proportional to the diffusion layer *** is observed that a medium interface thickness results in superior mechanical performance when compared to neither a greater nor a lesser interface *** characterization of all heat treatments reveals that the only intermetallic compound observed in the diffusion layers is TiAl_(3).Due to the inter-diffusion of Ti and Al atoms,the TiAl_(3) layer grows primarily at AA1050/TiAl_(3) interfaces.

关键词： Shear strength Co-extrusion Heat treatment Microstructure Intermetallic compounds

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