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Influence of the rainfall in the content of nutrients in litter in agroforestry systems managed with burning and without burning in Amazon

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Agricultural Sciences 2013年第11期4卷 26-36页

作者： Rosecélia Moreira Da Silva Castro Maria De Lourdes Pinheiro Ruivo Jorge Luiz Piccinin eraldo ferreira rodrigues Brazilian Company of Agricultural Research Statistical Department Belém Brasil Emilio Goeldi Pará Museum Coordination of Earth Sciences and Ecology Belém Brasil Federal University of Rural Amazonia Institute Sciences Agricultural Belém Brasil

This study evaluated the nutrient content of the litter, testing different treatments with burning and no burning, of the vegetation, to identify which one provides better efficiency in operation and production of nutrients in different seasonal conditions. The study area is located on the property of the family farmer, initially selected by a diagnosis socioeconomic, community Benjamin Constant, in northeastern Para. Litter was collected during two periods: dry season (November) and rainy (March) in 2009. For the collection of litter samples, we used collectors measuring (0.25 × 0.25 m2), which were placed directly on the soil surface. The collected material was stored in paper bags and taken to the laboratory for Chemical Analysis of the Brazilian Agricultural Research Corporation (EMBRAPA), which was determined by analyses of macronutrients (N, P, K, Ca, Mg, Na) and micronutrients (Fe, Cu, Mn, Zn). The highest concentrations of macronutrients were found in N for agroforestry systems with and without burning in two seasons (wet and dry). All macronutrients showed influence of seasonality, which was verified by the wide variation in nutritional behavior. The decreasing concentration of nutrients was presented N > Ca > Mg > Na > K > P in agroforestry system with burning, with maximum values of all nutrients in the rainy season, and N, P, K, Ca, Na in higher concentrations in agroforestry system without burning, and showed only the Mg peak in agroforestry system with burning. The behavior of the concentration of nutrients was opposite to that observed one, for all elements analyzed showed a reduction in the concentrations of nutrients in the dry season. The decreasing concentration of nutrients was presented Fe > Mn > Zn > Cu.

关键词： Forest Management Ecosystem Seasonality Litterfall

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The growth and production modeling of individual trees of Eucalyptus urophylla plantations

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Journal of Forestry Research 2020年第5期31卷 1663-1672页

作者： Joao Victor Nobre Carrijo Ana Beatriz de Freitas ferreira Marcela Costa ferreira Mario Cesar de Aguiar Eder Pereira Miguel eraldo Aparecido Trondoli Matricardi Alba Valeria Rezende Department of Forestry Faculty of TechnologyUniversity of Brası´liaBrası´lia 70910-900Brazil

Individual tree models(ITMs)are classified as growth and production models for projecting current and future forest *** are more complex than other growth and production models,show a higher level of detail and,consequently,produce a better modeling ***,the accuracy and efficiency of ITMs have not been properly assessed to *** this study,we estimated the growth in height,diameter,and individual tree volume of a Eucalyptus urophylla plantation by applying an *** used a continuing forest inventory dataset in which 1554 individual trees within 29 permanent plots were measured in the field over a 6-year period(24 to 72 months).Each individual tree volume was estimated for future tree *** achieve this,we adjusted the model to predict the height and diameter growth,and the probability of mortality as a function of the competition *** ITM accuracy was assessed based on the analysis of variance results and,subsequently,the multiple mean comparison test at the 5%significance *** tree volumes predicted by the ITM for the forest stand aged 72 months,beginning at ages 24,36,48,and 60 months,were compared to the field measured tree volume acquired from the 72-month forest inventory that was used as the reference *** and observed tree volumes were similar when the estimation was based on the 48-month forest *** results might help to reduce financial costs of forest inventory because the ITM produces accurate future predictions of forest stand *** estimated ITM for Eucalyptus plantations using measurement intervals up to 2 years is recommended because it significantly reduced the projected volume discrepancy compared to the field measurements.

关键词： Competition index Forest production Forest site Simulation models Tree mortality

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Fine-scale habitat differentiation shapes the composition, structure and aboveground biomass but not species richness of a tropical Atlantic forest

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Journal of Forestry Research 2020年第5期31卷 1599-1611页

作者： Alice Cristina rodrigues Pedro Manuel Villa Arshad Ali Walnir ferreira-Junior Andreza Viana Neri Laboratorio de Ecologia e Evoluc¸ao de Plantas–LEEP Departamento de Biologia VegetalUniversidade Federal de Vic¸osaVic¸osaMinas Gerais CEP 36570-900Brazil Fundacion para la Conservacion de la Biodiversidad Merida 7101MeridaVenezuela College of Forestry Nanjing Forestry UniversityNanjing 210037JiangsuPeople’s Republic of China Setor de Biologia e Meio Ambiente Instituto Federal do Sul de Minas Gerais-IFSULDEMINAS-Campus MachadoHighway Machado-Paraguac¸ukm 3MachadoMG CEP 37750000Brazil

Evaluating the influences of fine-scale habitat heterogeneity on the composition,diversity,structure and functioning of forests is critical to understand how tropical forests will respond to climate change and devise forest management strategies that will enhance biodiversity conservation and aboveground biomass ***,we hypothesized that topographic and soil factors determine fine-scale habitat differentiation,which in turn shape community composition,species richness,structure and aboveground biomass at the local scale in tropical *** test this hypothesis,we selected two areas(each 100×100 m)with contrasting fine-scale topographic conditions where all trees,palms and lianas with a diameter at breast height ≥ 10 cm were tagged and identified to *** each selected area,100 subplots of 10×10 m were *** mainly found that higher topographic variability caused higher habitat differentiation with changes in species composition and community structure,but did not change species *** habitat-scale analyses indicated that,in the less heterogeneous area,the distribution of species was more uniform along a fine-scale topographical gradient with no variation in convexity,which induced changes in structure and aboveground biomass,but not in species *** nonsignificant relationship between species richness and aboveground biomass may be attributable to species redundancy or functional *** study suggests that environmental filtering is a fundamental process for shaping community assembly and forest functioning along a local topographical gradient in tropical forests.

关键词： Community–habitat associations Convexity Rarefaction Topographic variability

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Epigenetic marks are modulated by gender and time of the day in the hippocampi of adolescent rats:a preliminary study

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Neural Regeneration Research 2018年第12期13卷 2160-2163页

作者： Viviane Rostirola Elsner Laura Reck Cechinel Louisiana Carolina ferreira de Meireles Karine Bertoldi Ionara rodrigues Siqueira Programa de Pós-Graduacao em Ciências Biológicas:Fisiologia Instituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do Sul Programa de Pós-Graduacao em Biociências e Reabilitacao Centro Universitário Metodista-IPA Curso de Fisioterapia Centro Universitário Metodista-IPA

Although the involvement of gender in epigenetic machinery in peripheral tissues during the neonatal period has been suggested, the gender-related epigenetic profile of brain areas during the adolescent period is rarely exploited. Furthermore, the influence of time of day on hippocampal acetylation marks has been demonstrated in young adult and aged rats; however, there are no studies reporting epigenetic changes in the adolescent period. Therefore, this study aimed to investigate the effects of gender on hippocampal DNA methyltransferase 1 content and histone deacetylase（HDAC） activity of adolescent rats at different time points, specifically early morning and afternoon. Both epigenetic markers increased significantly in the hippocampi of female rats compared to the male group, an indicator of reduced transcriptional activity. In addition, HDAC activity during the early morning was higher compared to afternoon groups in both male and female rats, while DNA methyltransferase 1 content was not altered by the time of day. Our findings demonstrate that hippocampal DNA methylation and histone acetylation status can be influenced by gender during the adolescent period, while the time of the day impacts HDAC activity.

关键词： adolescent rats DNA methyltransferase 1 histone deacetylase hippocampus time of the day gender epigenetic marks

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The CASTOR-K Code,Recent Developments and Applications

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Plasma Science and Technology 2015年第2期17卷 89-96页

作者： F.NABAIS D.BORBA R.COELHO A.FIGUEIREDO J.ferreira N.LOUREIRO P.rodrigues Associao EURATOM/IST Instituto de Plasmas e Fuso Nuclear-Instituto Superior TcnicoUniversidade de Lisboa

The CASTOR-K code is a hybrid magnetohydrodynamic （MHD）-drift kinetic code developed for the study of MHD modes in the presence of energetic ion populations. It allows a fast assessment of the linear stability of the modes, as well as an accurate calculation of damping due to thermal species （Landau damping）. These capabilities make the code an invaluable tool for parametric studies and data analysis. In recent years, CASTOR-K has been mostly used to analyze JET data, including the identification of mechanisms involved in the expulsion of energetic ions from the plasma. However, in order to prepare the code to be used for a wider range of tokamaks including ITER, the code is being subject to a series of important improvements. These improvements aim not only to introduce new physics in the code but also to make it capable of exchanging data with other codes through its integration in modelling infrastructures. In this paper a description of the CASTOR-K code is presented, as well as a summary of the most important results obtained with this code and a description of the new improvements being implemented.

关键词： controlled fusion tokamaks plasma instabilities magnetohydrodynamics(MHD) Alfven waves energetic particles

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Neutrino masses,cosmological inflation and dark matter in a variant U(1)B-L model with type II seesaw mechanism

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Chinese Physics C 2021年第2期45卷 621-630页

作者： J.G.rodrigues A.C.O.Santos J.G.ferreira Jr C.A.de S.Pires Departamento de Física Universidade Federal da ParaíbaCaixa Postal 500858051-970João PessoaPBBrasil Departamento de Física Universidade Federal do Rio Grande do Norte59078-970NatalRNBrasil

In this study,we implemented the type Ⅱ seesaw mechanism into the framework of the U(l)B-L gauge *** achieve this,we added a scalar triplet,A,to the canonical particle content of the U(l)B-Lgauge *** imposing that the U(l)B-L gauge symmetry be spontaneously broken at TeV scale,we show that the type Ⅱ seesaw mechanism is realized at an intermediate energy scale,more precisely,at approximately 109 *** prevent heavy right-handed neutrinos from disturbing the mechanism,we evoke a Z2 discrete ***,as a result,we have standard neutrinos with mass around eV scale and right-handed neutrinos with mass in TeV scale,with the lightest one fulfilling the condition of dark *** developed all of these in this *** addition,we show that the neutral component of Δ may perform unproblematic non-minimal inflation with loss of unitarity.

关键词： models beyond the standard model particle-theory and field-theory models of the early universe neutrino mass and mixing

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Gravitational and Quantum Effects in Neuron Function

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Journal of Life Sciences 2016年第6期10卷 273-278页

作者： Gustavo rodrigues ferreira Gomes International Center of Condensed Matter Physics University of Brasilia (UnB) Brasilia 70297-400 Distrito Federal Brazil

The relation between microtubules architecture in the cytoskeletal structure inside the dendrites and soma and the emergence of neuron function and firing action potential crosses the tiny line between physics and biology. As decoherence is a fundamental mechanism in some biological process such as photosynthesis and others examples, the gravitational quantum approach may contribute to elucidate if neuron function really emerges from quantum coherence in neuronal microtubules. The Einstein equation correlates the stress-energy tensor Tμv to a specific divergence-free combination Ricci tensor Rμv and the metric. In the semiclassical formulation, we have Gμv = Rμv -1/2gμvR=8πG/C^4〈ψ｜μvψ〉 which describes the quantum field in curved space-time geometry. But for a more precise equation in relation to the stress-energy tensor, we know that in a non-zero temperature, the wave-function is not enough to describe the physical reality. A more precise equation demands a formulation in the density-matrix form but for now there is no Diosi-Penrose model with density-matrix formulation. Such a density-matrix description can be viewed as a probability mixture of different wave-functions. Using some algebra and rules related to the mathematical manipulation of the density-matrix applied to operators, such the stress energy tensor, we found the von Neumann-Einstein equation for the general relativity equation in the density matrix operator form, Gμv = 8πG/C^4Tr[pTμv]. Thus density-matrix operator--instead of just a wave function of pure states--applied to the stress-energy tensor gives the curvature of space time, given by Einstein tensor, Gμv. The quantum fluctuation in the gravitational space-time field might feed back to decohere the quantum density-matrix. As long as decoherence can be viewed as the loss of information from a system to the environment, the density-matrix p is also related to that process and considering the measurement problem, density-matrix /garter is a more

关键词： Semiclassical equation quantum gravity decoherence microtubulin neuron function.

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Ammonium Improves Corn Phosphorus Acquisition Through Changes in the Rhizosphere Processes and Root Morphology

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Pedosphere 2019年第4期29卷 534-539页

作者： Elialdo Alves DE SOUZA Natália rodrigues ferreira-ELOY Camila da Silva GRASSMANN Ciro Antonio ROSOLEM Philip J.WHITE School of Agronomic Sciences Sao Paulo State University The James Hutton Institute

Dear Editor, Phosphorus (P) deficiency is the most limiting factor in tropical agriculture since most soils in this region are predominantly acids with high-energy P-binding compounds. Therefore, up to 90% of the P applied becomes fixed in soils, which raises environmental concerns and production costs (Syers et al., 2008). Thus, developing strategies to imptove P use efficiency (PUE) is essential to mitigate environmental problems and improve profits. These strategies should consider the soil-root-rhizosphere system because it is the most biochemical active site where nutrient uptake occurs (Hinsinger, 2011).

关键词： Root Morphology Rhizosphere Processes Dear Editor

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Enhancement of seed germination in Macaranga peltata for use in tropical forest restoration

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Journal of Forestry Research 2014年第4期25卷 897-901页

作者： Cassie R.rodrigues Bernard F.rodrigues Department of Botany Goa University Goa 403206 India

We used pre-sowing treatments v/z., soaking seeds in concen- trated sulphudc acid （CSA）, gibberellic acid （GA）, combined treatment of CSA ＋ GA and mechanical scarification to overcome seed dormancy and enhance synchronous germination of Macaranga peltata seeds. We analysed percent seed germination data by logistic regression and con- finned that except in GA treatment, time and acid concentration together were crucial for enhancing germination. The combination treatment of CSA and GA resulted in higher percent germination （up to 74%） than either treatment used separately, but produced defective seedlings （26%）. Mechanical scarification of seed coat had the greatest impact in enhanc- ing germination （78%） and reducing imbibition time （6 days） against the control （0%）. Germination studies and SEM analysis confirmed that seed germination in M. peltata was inhibited by seed coat dormancy.

关键词： dormancy gibberellic acid (GA) mechanical scarification restoration seed coat

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Autoimmune hepatitis in childhood: The role of genetic and immune factors

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World Journal of Gastroenterology 2013年第28期19卷 4455-4463页

作者： Priscila Menezes Ferri Liu Débora Marques de Miranda Eleonora Druve Tavares Fagundes Alexandre rodrigues ferreira Ana Cristina Simoes e Silva Department of Pediatrics Interdisciplinary Laboratory of Medical Investigation Federal University of Minas Gerais Belo Horizonte Minas Gerais 30130-100 Brazil National Institute of Science and Technology of Molecular Medicine (INCT-MM) CNPq-FAPEMIG Federal University of Minas Gerais Belo Horizonte Minas Gerais 30130-100 Brazil

Autoimmune hepatitis (AIH) is a rare chronic inflammatory disease of the liver, which affects a group of patients who lost their immunological tolerance to antigens of the liver. It is clinically characterized by hypergammaglobulinemia, elevated liver enzymes, presence of autoantibodies and histological changes. Although being rare in children, it represents a serious cause of chronic hepatic disease that can lead to cirrhosis and hepatic failure. Clinical findings, exclusion of more common liver disorders and the detection of antibodies antinuclear antibodies, smooth muscle antibodies and anti-LKM1 are usually enough for diagnosis on clinical practice. The pathogenic mechanisms that lead to AIH remain obscure, but some research findings suggest the participation of immunologic and genetic factors. It is not yet knew the triggering factor or factors that stimulate inflammatory response. Several mechanisms proposed partially explain the immunologic findings of AIH. The knowledge of immune factors evolved might result in better markers of prognosis and response to treatment. In this review, we aim to evaluate the findings of research about genetic and immune markers and their perspectives of application in clinical practice especially in pediatric population.

关键词： Autoimmune hepatitis Genetics Clinical practice Immunophenotype

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