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Litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon

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Journal of Forestry Research 2024年第3期35卷 131-141页

作者： Ricardo Antonio marenco Saul Alfredo Antezana-Vera Daniela Pereira Dias luiz Antonio Candido Instituto Nacional de Pesquisas da Amazonia Coordenagao de Uso da Terra e Mudanca ClimaticaAv.Andre Araujo 2936ManausAM69067-375Brazil Programa de pos-Graduagao em Agricultura no Tropico Umido Instituto Nacional de Pesquisas da Amazonia-INPAManausAMBrazil Unidade Academica de Ciencias Agrarias Universidade Federal de JataiBR 364km 195JataiGO 75801-615Brazil

Litterfall is the largest source of nutrients to for-est soils of tropical ***,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central *** study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central *** was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates *** area index was also recorded in the dry and rainy *** litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy *** seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality *** phosphorous increased,potassium decreased during the dry *** seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf ***,the five nutrients had similar remobilization rates over the *** absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change.

关键词： Throughfall Nutrient cycling Climatic seasonality Leaf mass per area

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Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the mediterranean Andes

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Ecological Processes 2024年第01期13卷 132-143页

作者： luiz Santini Jr. Dylan Craven Daigard Ricardo Ortega Rodriguez manolo Trindade Quintilhan Stephanie Gibson-Carpintero Cristina Aravena Torres Fidel A.Roig Ariel A.mu?oz Alejandro Venegas-Gonzalez Hémera Centro de Observación de la Tierra Universidad Mayor GEmA Center for Genomics Ecology and Environment Universidad Mayor Data Observatory Foundation ANID Technology Center Depart-ment of Forest Sciences ESALQ-University of Sao Paulo Department of Plant Biology Institute of Biology University of Campinas Instituto de Geografía Universidad Nacional Autónoma de México (UNAM) Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICET ) Institute of Geography Pontificia Universidad Católica de Valparaíso Instituto de Ciencias Agroalimentarias Animales y Ambientales (ICA3) Universidad de O'Higgins

Background Treeline ecotones of mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the phys-iology of woody plants. The mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. Here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought *** We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution(31–35° SL) based on anatomical(vessel structure and distribution) and physiological(intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii) megadrought(2008–2018) and(iii) hyperdrought(2019–2020). The variables were annualized and analyzed by linear mixed-effects *** Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought *** Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may incre

关键词： Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change

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Deforestation in Latin America in the 2000s predominantly occurred outside of typical mature forests

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The Innovation 2024年第3期5卷 88-98页

作者： Zhiyu Zhang Wenjian Ni Shaun Quegan Jingming Chen Peng Gong luiz Carlos Estraviz Rodriguez Huadong Guo Jiancheng Shi Liangyun Liu Zengyuan Li Yating He Qinhuo Liu Yosio Shimabukuro Guoqing Sun Key Laboratory of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Shijingshan DistrictBeijing 100049China Chinal of mathematics and Statistics University of SheffieldSheffield S37RHUK Department of Geography and Program in Planning University of TorontoTorontoON M5S 3G3Canada Department of Earth Sciences and Department of Geography University of Hong KongHong KongChina Forest Science Department Luiz de Queiroz College of AgricultureUniversity of São PauloAv.Pádua Dias11Piracicaba 13418-900Brazil National Space Science Center Chinese Academy of SciencesBeijing 100190China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing 100091China Research Institute of Forest Policy and Information Chinese Academy of ForestryBeijing 100091China Remote Sensing Department National Institute for Space Research(INPE)Av.dos Astronautas 1758São Josédos Campos 12227-010Brazil Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA

The role of tropical forests in the global carbon budget remains controversial,as carbon emissions from deforestation are highly *** high uncertainty arises from the use of either fixed forest carbon stock density or maps generated from satellite-based optical reflectance with limited sensitivity to biomass to generate accurate estimates of emissions from *** space missions aiming to accurately map the carbon stock density rely on direct measurements of the spatial structures of forests using lidar and *** found that lost forests are special cases,and their spatial structures can be directly measured by combining archived data acquired before and after deforestation by space missions principally aimed at measuring ***,using biomass mapping,we obtained new estimates of carbon loss from deforestation ahead of forthcoming space ***,using a high-resolution map of forest loss and the synergy of radar and lidar to estimate the aboveground biomass density of forests,we found that deforestation in the 2000s in Latin America,one of the severely deforested regions,mainly occurred in forests with a significantly lower carbon stock density than typical mature forests.

关键词： forest Latin lidar

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CFD predictions for hazardous area classification

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Chinese Journal of Chemical Engineering 2019年第1期27卷 21-31页

作者： Andrey Oliveira de Souza aurélio m.reira luiz Ant?nio Tavernard Pereira Neto Ant?nio Carlos Brandao de Araujo Heleno Bispo da Silva Sidinei Kebler da Silva Jose Jailson Nicacio Alves Federal Institute of Education Science and Technology of Paraiba Petrobras-Petróleo Brasileiro S.A. Federal University of Campina Grande

This study aimed to describe a Computational Fluid Dynamics(CFD) procedure using the ANSYS CFX software 16.1 and Design of Experiments for the determination of volume and extension of explosive atmospheres due to fugitive emissions of flammable *** multidimensional statistical sampling technique Latin Hypercube was used, which defined 100 simulations of random methane gas leak *** CFD model proved to be robust in predicting the extension and volume of the explosive atmosphere for orifice diameters from 0.1 to2.5 mm, pressure from 0.1 mPa to 12 mPa and temperatures from 0 ℃ to 400 ℃.It was found that the calculation domain must be parameterized 8 m in length for each millimeter of the diameter of the source of release to ensure the *** order not to lose precision for very small diameters, the mesh was parameterized with 50 elements along the orifice *** was proved that gravity does not influence the extension and volume of the explosive atmosphere at sonic *** deviation from the ideal gas behavior in the reservoir,achieved by applying the Soave–Redlich–Kwong equation of state, also has not significantly influenced the extension and volume of the explosive *** results showed that the size of the explosive atmosphere varies directly with the diameter of the source emission and reservoir pressure, and inversely with the temperature of the *** diameter of the source is the parameter that has the major effect on the extension of the explosive atmosphere, followed by the pressure and lastly the temperature of the reservoir.

关键词： Computational Fluid Dynamics Computer simulation Safety Fugitive emissions Classified area Flammable gas cloud

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Increasing pancreatic cancer is not paralleled by pancreaticoduodenectomy volumes in Brazil:A time trend analysis

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Hepatobiliary & Pancreatic Diseases International 2019年第1期18卷 79-86页

作者： Lucila m Perrotta de Souza Jessica PL m.reira Homero S Fogaca José marcus Raso Eulálio Ronir R luiz Heitor SP de Souza Department of Internal medicine School of Medicine Federal University of Rio de Janeiro Institute of Public Health Studies (IESC) Federal University of Rio de Janeiro Department of Surgery School of Medicine Federal University of Rio de Janeiro D’Or Institute for Research and Education

Background: Currently, surgical resection represents the only curative treatment for pancreatic cancer(PC), however, the majority of tumors are no longer resectable by the time of diagnosis. The aim of this study was to describe time trends and distribution of pancreaticoduodenectomies(PDs) performed for treating PC in Brazil in recent years. methods: Data were retrospectively obtained from Brazilian Health Public System(namely DATASUS) regarding hospitalizations for PC and PD in Brazil from January 2008 to December 2015. PC and PD rates and their mortalities were estimated from DATASUS hospitalizations and analyzed for age, gender and demographic characteristics. Results: A total of 2364 PDs were retrieved. Albeit PC incidence more than doubled, the number of PDs increased only 37%. most PDs were performed in men(52.2%) and patients between 50 and 69 years old(59.5%). Patients not surgically treated and those 70 years or older had the highest in-hospital mortality rates. The most developed regions(Southeast and South) as well as large metropolitan integrated municipalities registered 76.2% and 54.8% of the procedures, respectively. LmIm PD mortality fluctuated, ranging from 13.6% in 2008 to 11.8% in 2015. Conclusions: This study suggests a trend towards regionalization and volume-outcome relationships for PD due to PC, as large metropolitan integrated municipalities registered most of the PDs and more stable mortality rates. The substantial differences between PD and PC increasing rates reveals a limiting step on the health system resoluteness. Reduction in the number of hospital beds and late access to hospitalization, despite improvement in diagnostic methods, could at least in part explain these findings.

关键词： Pancreatic cancer Pancreaticoduodenectomy Time trend analysis Ecological study Hospitalization rates mortality rates

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Dipole (hyper)polarizabilities of neutral silver clusters

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Chinese Physics B 2016年第12期25卷 217-222页

作者： Francisco E Jorge luiz G m de macedo Departarnento de Fisica Universidade Fedoral do Espirito Santo 29060-900 Vitoria Brazil Unidade Academica de Fisica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Faculdade de Biotecnologia ICB Universidade Federal do Para 66075-110 Belem Brazil

At the Douglas-Kroll-Hess （DKI4） level, the B3PW91 functional along with the all-eleclron relativistic basis sets of valence triple and quadruple zeta qualities are used to determine the structure, stability, and electronic properties of the small silver clusters （Agn, n ≤ 7）. The results presented in this study are in good agreement with the experimental data and theoretical values obtained at a higher level of theory from the literature. Static polarizability and hyperpolarizability are also reported. It is verified that the mean dipole polarizability per atom exhibits an odd-even oscillation and that the polarizability anisotropy is directly related to the cluster shape. In this article, the first study of hyperpolarizabilities of small silver clusters is presented. Except for the monomer, the second hyperpolarizabilities of the silver clusters are significantly larger than those of the copper clusters.

关键词： B3PW91 functional all-electron basis sets non-relativistic and DKH2 calculations silver clusters,dipole (hyper)polarizabilities

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Water availability drives gradients of tree diversity,structure and functional traits in the Atlantic-Cerrado-Caatinga transition,Brazil

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Journal of Plant Ecology 2018年第6期11卷 803-814页

作者： marcela de Castro Nunes Santos Terra Rubens manoel dos Santos Jamir Afonso do Prado Júnior José marcio de mello José Roberto Soares Scolforo marco aurélio Leite Fontes Ivan Schiavini Aliny Aparecida dos Reis Inacio Thomaz Bueno luiz Fernando Silva magnago Hans ter Steege Departamento de Ciências Florestais Universidade Federal de LavrasCampus UniversitárioPO Box 3037LavrasMinas Gerais 37200-000Brazil Instituto de Biologia Universidade Federal de UberlândiaCampus Umuarama-Bloco 2DPO Box 593UberlândiaMinas Gerais 38400-902Brazil Applied Ecology and Conservation Lab Programa de Pós‐graduação Ecologia e Conservação da BiodiversidadeUniversidade Estadual de Santa CruzIlhéusBahia 45662-900Brazil Naturalis Biodiversity Center Vondellaan 55Postbus 95172300 RA LeidenThe Netherlands Coordenação de Botânica Museu Paraense Emílio GoeldiAv.Magalhães Barata 376PO Box 399BelémPara´66040-170Brazil

Aims Climate and soil are among the most important factors determin-ing variation in tree communities,but their effects have not been thoroughly elucidated to date for many vegetation *** this study,we evaluate how climate and soil gradients affect gradients of vegetation composition,species diversity and dominance,structure and functional traits(seed mass and wood density)using over 327000 trees in 158 sites distributed along environmental gradients in the transitions among the Atlantic forest,Cerrado and Caatinga in minas Gerais State(mG),Brazil(nearly 600000 km2).methods Gradients in species,genus and family abundance in addition to basal area,stem density,species diversity(Fisher’s alpha),domin-ance percentage,seed mass and wood density were correlated using multiple regressions with environmental variables,as summarized in four principal component analysis axes(two climatic-precipi-tation seasonality and temperature range-and two edaphic-soil fertility and soil moisture).Additionally,ordinary kriging maps were used to better illustrate the *** Findings multiple regression models indicate that all variables but domin-ance percentage were affected by one or more of the environmental gradients,but the average R2 was low(26.25%).Kriging maps rein-forced the patterns observed in the regression *** seasonality and soil moisture gradients were the most important gra-dients affecting vegetation *** finding suggests that water availability is an important determinant of vegetation features in these vegetation transitions.

关键词： climate environmental gradient soil southeastern Brazil vegetation

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Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients

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Journal of Sport and Health Science 2024年第4期13卷 548-558,F0003页

作者： Hugo de Luca Correa Lysleine Alves Deus Dahan da Cunha Nascimento Nicholas Rolnick Rodrigo Vanerson Passos Neves Andrea Lucena Reis Thais Branquinho de Araujo Carmen Tzanno-martins Fernanda Silveira Tavares luiz Sinesio Silva Neto Claudio Avelino Rodrigues Santos Paolo Lucas Rodrigues-Silva Fernando Honorato Souza Vitoria marra da motta Vilalva mestrinho Rafael Lavarini dos Santos Rosangela Vieira Andrade Jonato Prestes Thiago dos Santos Rosa Post-graduate Program of Physical Education Catholic University of BrasıliaBrasılia 71966-700Brazil The Human Performance mechanic Lehman CollegeNew YorkNY 10011USA Clinical Group Home Dialysis Center and RenalClass Sao Paulo 01239-040Brazil Department of medicine Catholic University of BrasıliaBrasılia 71966-700Brazil Faculty of medicine Federal University of TocantinsTocantins 77001-090Brazil Embrapa Genetic Resources and Biotechnology Brasılia 70770-917Brazil Graduate Program of Genomic Sciences and Biotechnology Brasılia 71966-700Brazil

Background:Hemodialysis(HD) per se is a risk factor for *** the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training *** aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE) with BFR on this ***:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of mL/min/1.73 m2).The RE+BFR session consisted of 50% arterial occlusion pressure during 50 min sessions of HD(intradialytic exercise).RE repetitions included concentric and eccentric lifting phases(each lasting 2 s) and were supervised by a strength and conditioning ***:Several variables were associated with elevated levels of D-dimer,including higher blood glucose,citrate use,recent cardiovascular events,recent intercurrents,higher inflammatory status,catheter as vascular access,older patients(>70 years old),and HD ***,RE+BFR significantly increases D-dimer after 4 *** with borderline baseline D-dimer levels(400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range(≥500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR.

关键词： Blood-flow restriction Chronic kidney disease Coagulation Hemodialysis Vascular occlusion exercises

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Hyperonic neutron stars: reconciliation between nuclear properties and NICER and LIGO/VIRGO results

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Communications in Theoretical Physics 2022年第1期74卷 57-63页

作者： luiz L Lopes Centro Federal de Educagao Tecnologica de minas Gerais Campus VIII CEP 37.022-560Varginha-MG-Brasil

Using an extended version of quantum hadrodynamics,I propose a new microscopic equation of state(EoS)that is able to correctly reproduce the main properties of symmetric nuclear matter at the saturation density,as well as produce massive neutron stars and satisfactory results for the radius and the tidal parameter.I show that this EoS can reproduce at least a 2.00 solar mass neutron star,even when hyperons are *** constraints about the radius of a 2.00 m_(⊙) and the minimum mass that enables a direct Urea effect are also checked.

关键词： neutron star nuclear matter tidal deformability DU process hyperons

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Evaluation of the mechanisms Acting on the Atlantic meridional Overturning Circulation in CESm2 for the 1pctCO_(2) Experiment

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Journal of Atmospheric Science Research 2024年第1期7卷 40-58页

作者： Lívia Sancho Elisa Passos marcio Cataldi luiz Paulo de Freitas Assad luiz Landau Laboratory of Computational methods in Engineering Civil Engineering ProgramAlberto Luiz Coimbra Institute for Graduate Studies and Research in EngineeringFederal University of Rio de JaneiroRio de Janeiro21941-617Brazil Civil Engineering Program Alberto Luiz Coimbra Institute for Graduate Studies and Engineering ResearchFederal University of Rio de JaneiroRio de Janeiro21941-617Brazil Physical Oceanography Laboratory Department of Physical OceanographyFaculty of OceanographyRio de Janeiro State UniversityRio de Janeiro20559-900Brazil Climate System monitoring and modeling Laboratory Water Resources and Environmental EngineeringFluminense Federal University24020-140Brazil Regional Atmospheric modeling Group(mAR) Physics of the EarthDepartment of PhysicsRegional Campus of International Excellence(CEIR)“Campus Mare Nostrum”University of MurciaMurcia30100Spain Department of meteorology Institute of GeosciencesFederal University of Rio de JaneiroRio de Janeiro21941-617Brazil

The Atlantic meridional Overturning Circulation(AmOC)is a crucial component of the Earth’s climate system due to its fundamental role in heat distribution,carbon and oxygen transport,and the *** climate components,such as the atmosphere and sea ice,influence the *** the physical mechanisms of those interactions is paramount to increasing knowledge about AmOC’s *** this study,the authors used outputs from the Community Earth System model version 2 and observational data to investigate changes in theAmOC and the associated physical *** DECK experiments were evaluated:piControl and 1pctCO_(2),with an annual increase of 1%of atmospheric CO_(2).The analysis revealed a significant decrease in the AmOC,associated with changes in mixed layer depth and buoyancy in high latitudes of the North Atlantic,resulting in the shutdown of deep convection and potentially affecting the formation of North Atlantic Deep Water and Antarctic Bottom Water.A vital aspect observed in this study is the association between increased runoff and reduced water evaporation,giving rise to a positive feedback ***,the rates of freshwater spreading have intensified during this period,which could lead to an accelerated disruption of the AmOC beyond the projections of existing models.

关键词： AmOC meridional cell Climate change Deep circulation CESm2 results CmIP6

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