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Temporal and phenological profiles of open and dense Caatinga using remote sensing:response to precipitation and its irregularities

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Journal of Forestry Research 2021年第3期32卷 1067-1076页

作者： Janisson Batista de Jesus Tatiana Mora Kuplich íkaro daniel de carvalho barreto Cristiano Niederauer da Rosa Fernando Luis Hillebrand Postgraduate Program in Remote Sensing Federal University of Rio Grande Do SulAv.Bento GoncalvesCEP 91501-970Porto AlegreRio Grande do Sul 9500Brazil National Institute for Space Research(INPE)Southern Regional Centre(CRS) CEP 97105-970Santa MariaRio Grande do SulBrazil Postgraduate Program in Applied Biometrics and Statistics Rural Federal University of PernambucoDom Manuel de Medeiross/nDois IrmaosCEP 52171-900RecifePernambucoBrazil

Caatinga is a typical biome of Brazil's semiarid regions and subject to climate *** is needed on the relation of its features to climate *** study analyzed the infl uence of rainfall and its irregularities in open and dense woody Caatinga *** curves were generated by means of Normalized Difference Vegetation Index(NDVI)time profiles in the Grota do Angico Conservation Unit study area in Sergipe *** data from 2000 to 2018 were collected and phenological curves generated using various estimate methods that produced the following variables:[start of season,end of season,peak of season position,length of season,mean growing season and maximum seasonal].Rainfall showed a standard intra-annual behavior,with inter-annual variations related to irregularities infl uencing Caatinga *** Caatinga vegetation had higher values of NDVI in all periods,even in anomalous years compared to open Caatinga,in addition to having longer leaf coverage over the year,with an anticipated start and a more extended seasonal *** analysis of the rainfall regime made it possible to assess its infl uence on the Caatinga and phenological profiles proved to be fundamental to understand periods of physiological change of open and dense *** results indicate that dense Caatinga maintains physiological activity longer,which may be associated with greater moisture maintenance in a semiarid *** addition,because it has a greater leaf cover for longer periods,the soil may be preserved and maintain its characteristics longer,reducing the effects of *** results may be associated with the type of forest management and conservation in this *** total or partial suppression of individual remnants of Caatinga should be avoided,since the most open areas have lower photosynthetic capacity,affected to a considerable extent from the effects of adverse climatic ***,open Caatinga has a reduced cap

关键词： Semiarid Tropical dry forest NDVI MODIS Phenopix

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Duration and intensity of rainfall events with the same erosivity change sediment yield and runoff rates

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International Soil and Water Conservation Research 2021年第1期9卷 69-75页

作者： Wilk Sampaio de Almeida Steffen Seitz Luiz Fernando Coutinho de Oliveira daniel Fonseca de carvalho Agronomy department Federal Institute of EducationScience and Technology of RondôniaCampus AriquemesRO 257km 13AriquemesRO76870-000Brazil department of Geosciences University of TübingenTübingenGermany Federal University of Lavras Department of Water Resources and Sanitation37200-000LavrasMGBrazil Federal Rural University of Rio de Janeiro Engineering DepartmentBR 465km 723897-000SeropédicaRJBrazil

The effect of different rainfall patterns on surface runoff,infiltration and thus soil losses and sediment concentrations are still in the focus of current *** most simulated rainfall experiments,pre-cipitation is applied at a fixed intensity for a fixed ***,the impact of rainfall patterns on soil erosion processes may be different varying the rainfall duration and intensity that produces an event with similar rainfall erosivity ***-five rainfall events were applied on micro-scale runoff plots in a soil covered with corn straw to evaluate the sediment yield and runoff *** different rainfall types were composed by association of duration(Dur)and intensity(IP)with the same erosivity *** Dur varied from 38 to 106 min and the IP varied from 75.0 to 44.6 mm h^(-1).The sediment yield varied from 1.89±1.26 g m^(-2) to 4.02±2.66 g m^(-2) and runoff ranged from 16.9±8.74 mm to 32.63±10.67 mm with highest rates occurring with high intensity and low *** highest rainfall intensity provides the maximum sediment yield(0.138 g m^(-2) min^(-1))and runoff rates(0.87 mm min^(-1)).The time to start surface runoff varied from 14 to 19.2 min and it was longer in treatments with longer durations and low precipitation *** difference was found in the amount of sediments applying rain with the same erosivity and different associations of duration and ***,the intensity and duration of the rain,with the same erosivity,altered the amount and time of *** rainfall experiments with con-stant intensity and fixed time,the erosion rates depend on the duration of the applied ***,the results of this study can contribute to the development of new perspectives in the design of water erosion experiments with simulated rain considering the duration,intensity and also the association of these variables to produce rainfall that delivery the same soil erosion capacity.

关键词： Simulated rainfall Rainfall pattern Water erosion Soil loss

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Improving wood volume predictions in dry tropical forest in the semi-arid Brazil

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Journal of Arid Land 2020年第6期12卷 1046-1055页

作者： Robson B de LIMA Patrícia A B barreto-GARCIA Alessandro de PAULA Jhuly E S PEREIRA Flávia F de carvalho Silvio H M GOMES department of Forest Engineering State University of AmapáMacapá68900070Brazil department of Forest Science State University of Southwest BahiaVitória da Conquista 45083900Brazil Universidade Federal de Lavras Lavras 37200900Brazil Universidade de São Paulo Piracicaba 13418900Brazil

The volumetric variability of dry tropical forests in Brazil and the scarcity of studies on the subject show the need for the development of techniques that make it possible to obtain adequate and accurate wood volume *** this study,we analyzed a database of thinning trees from a forest management plan in the Contendas de SincoráNational Forest,southwestern Bahia State,*** data set included a total of 300 trees with a trunk diameter ranging from 5 to 52 ***,validation and statistical selection of four volumetric models were *** to the difference in height values for the same diameter and the low correlation between both variables,we do not suggest models which only use the diameter at breast height(DBH)variable as a predictor because they accommodate the largest estimation *** comparing the best single entry model(Hohenald-Krenn)with the Spurr model(best fit model),it is noted that the exclusion of height as a predictor causes the values of 136.44 and 0.93 for Akaike information criterion(AIC)and adjusted determination coefficient(R2 adj),which are poorer than the second best model(Schumacher-Hall).Regarding the minimum sample size,errors in estimation(root mean square error(RMSE)and bias)of the best model decrease as the sample size increases,especially when a larger number of trees with DBH≥15.0 cm are randomly *** sampling by diameter class produces smaller volume prediction errors than random sampling,especially when considering all *** summary,the Spurr and Schumacher-Hall models perform *** models suggest that the total variance explained in the estimates is not less than 95%,producing reliable forecasts of the total volume with *** estimates indicate that the bias around the average is not greater than 7%.Our results support the decision to use regression methods to build models and estimate their parameters,seeking stratification strategies in diameter classes for the sample trees.

关键词： volume modeling minimal sample size Caatinga Spurr model forest management

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Soil loss and runoff obtained with customized precipitation patterns simulated by InfiAsper

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International Soil and Water Conservation Research 2022年第3期10卷 407-413页

作者： daniel Fonseca de carvalho Pietro Menezes Sanchez Macedo Marinaldo Ferreira Pinto Wilk Sampaio de Almeida Nivaldo Schultz department of Engineering Institute of TechnologyFederal Rural University of Rio de JaneiroSeropedicaRio de JaneiroBrazil Postgraduate Program in Agronomy-Soil Sciences Federal Rural University of Rio de JaneiroSeropedicaRio de JaneiroBrazil Agronomy department Federal Institute of EducationScience and Technology of RondoniaCampus AriquemesRO 257Km 13AriquemesRO76870-000Brazil department of Soil Science Institute of AgronomyFederal Rural University of Rio de JaneiroSeropedicaRJBrazil

Applying constant precipitation intensity,which does not occur in natural events,is one of the main limitations concerning rainfall simulators in soil erosion *** present work evaluated the InfiAsper rainfall simulator operating with a new control panel to program rainfalls with different precipitation intensities(PI).Infiltration rates and soil and water losses were evaluated in a Distrophic Acrisol(clay loam texture)with simulated rainfalls of 30 mm and duration of 40 min,considering advanced(AD),intermediate(IN),delayed(de),and inverted intermediate(II)patterns,all with PI peaks of 110 mm h^(-1),and a constant(CT)*** experimental design was in randomized blocks with five treatments(rainfall patterns)and experimental units measuring 2.5×2.5 *** simulator worked satisfactorily,applying the rainfall according to the preconfigured *** simulated rainfall with the CT and II patterns did not promote runoff nor soil *** and runoff rates varied according to the applied rainfall pattern,reaching 97.8 and 27.3 mm h^(-1)(AD),82.1 and 39.5 mm h^(-1)(IN),and 76.2 and 49.7 mm h^(-1)(de),*** loss and surface runoff totaled each 4.77 g m^(-2)and 3.9 mm(AD),6.70 g m^(-2)and 6.8 mm(IN),and 6.03 g m^(-2)and 7.0 mm(de).The InfiAsper simulator modified enables varying precipitation intensity besides obtaining satisfactory results in the field and information consistent with the expected characteristics of natural rainfall *** the intermediate and delayed rainfall patterns,soil and water losses are higher than in the advanced.

关键词： Water erosion Rainfall simulator Precipitation intensity

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Simulated rainfall in Brazil:An alternative for assesment of soil surface processes and an opportunity for technological development

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International Soil and Water Conservation Research 2024年第1期12卷 29-42页

作者： Camila Calazans da Silva Luz Wilk Sampaio de Almeida Adilson Pacheco de Souza Nivaldo Schultz Jamil Alexandre Ayach Anache daniel Fonseca de carvalho Postgraduate Program in Agronomy-Soil Sciences Federal Rural University of Rio de JaneiroSeropédicaRJBrazil Agronomy department Federal Institute of EducationScience and Technology of RondôniaAriquemesROBrazil Federal University of Mato Grosso SinopMTBrazil Federal Rural University of Rio de Janeiro SeropédicaRJBrazil Federal University of Mato Grosso do Sul Campo GrandeMSBrazil

Rainfall simulators(RS)have been used,above all,to evaluate hydrological processes related to soil water infiltration,surface runoff and soil *** allow repeatability of rain application with different precipitation intensities in field and/or laboratory conditions and should produce events with physical characteristics similar to natural *** this manuscript,we carried out a bibliometric and scientometric analysis of studies with simulated rainfall in Brazil to assess the temporal evolution of publications,the main topics addressed and the degree of technological development of the *** searched for the terms“rainfall simulator”OR“simulated rainfall”AND“Brazil”in the Scopus,Web of Science,SciELO and Google Scholar *** found 143 articles published in the last 37 years(1985-2022).Our findings indicate that the main research areas covered in papers are soil erosion(57.34%),soil water infiltration(24.47%),nutrient losses(9.8%)and RS development and calibration/assessment(8.39%).In recent years,the number of published papers in international high-impact factor journals has *** of the papers(49.65%)refer to studies carried out by institutions located in the south and southeast regions of ***,there is a large gap of studies on simulated rainfall in other regions of Brazil,where important biomes such as the Cerrado,Amazon,Caatinga,and their transitions are *** study informs research priorities on soil erosion under simulated rainfall and provides a bibliographic database that can assist in more detailed future analyses.

关键词： Rainfall simulator Soil and water losses Soil water infiltration Bibliometrics Scientific review

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Encephalic hemodynamic phases in subarachnoid hemorrhage:how to improve the protective effect in patient prognoses

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Neural Regeneration Research 2015年第5期10卷 748-752页

作者： Marcelo de Lima Oliveira daniel Silva de Azevedo Milena Krajnyk de Azevedo Ricardo de carvalho Nogueira Manoel Jacobsen Teixeira Edson Bor-Seng-Shu Division of Neurological Surgery Hospital das ClinicasSchool of MedicineUniversity of Sao Paulo

Subarachnoid hemorrhage is frequently associated with poor prognoses. Three different hemo- dynamic phases were identified during subarachnoid hemorrhage： oligemia, hyperemia, and vasospasm. Each phase is associated with brain metabolic changes. In this review, we correlated the hemodynamic phases with brain metabolism and potential treatment options in the hopes of improving patient prognoses.

关键词： hemodynamic phases cerebral subarachnoid hemorrhage metabolic crises

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Apparent soil electrical conductivity in the delineation of management zones for cocoa cultivation

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Information Processing in Agriculture 2022年第3期9卷 443-455页

作者： Samuel de Assis Silva Railton Oliveira dos Santos daniel Marcal de Queiroz Juliao Soares de Souza Lima Levi Fraga Pajehua Caique carvalho Medauar Center for Agricultural Sciences and Engineering Federal University of Espirito SantoAlegre CampusEspirito Santo 29500-000Brazil department of Agricultural Sciences Santa Cruz State UniversityIlheusBahia 45662-900Brazil department of Agricultural Engineering Federal University of Vic¸osaVic¸osaMinas Gerais 36570-900Brazil

Apparent electrical conductivity is an important parameter for describing the spatial vari-ability of physical and chemical attributes of the soil and for the delineation of manage-ment *** objective of this work is to outline management zones for the cocoa cultivation based on the spatial variability of the productivity and the apparent electrical conductivity(ECa)of the *** collection was performed in a regular sample grid con-taining 120 points in an area cultivated with cocoa trees,located in the municipality of Ilhe´us,state of Bahia,*** each sampling point(cocoa tree),soil samples were col-lected to determine chemical *** was measured for one year,counting,monthly,the number of fruits,which were classified into off-season cocoa,harvest and annual *** of the apparent electrical conductivity of the soil were performed at different times of the year using a portable conductivity *** data were analyzed using classical statistics and *** management zones were delin-eated using the fuzzy k-means *** ideal number of class was defined using the fuzziness performance index(FPI)and the entropy of the modified partition(MPE)*** Kappa coefficient was used to validate the management zones,assessing their agreement with the chemical attributes of the *** ECa of the soil values pre-sented moderate temporal variation,with maximum amplitude of 19.37 mS m1 and min-imum of 0.82 mS m1 between measurement periods;higher averages of the ECa coincided with the highest levels of water in the *** measurements of the ECa of the soil carried out in April and October showed greater correlation with the chemical attributes of the soil,with significant values for 11 and 8 of the 17 attributes evaluated,*** man-agement zones from the ECa measured in April showed:a)reduced number of classes;b)spatial continuity between classes,and;c)agreement from reasonable(kappa between

关键词： Theobroma cacao Precision agriculture Spatial variability Fuzzy k-means

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New approach for obtaining the C-factor of RUSLE considering the seasonal effect of rainfalls on vegetation cover

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International Soil and Water Conservation Research 2021年第2期9卷 207-216页

作者： Pietro Menezes Sanchez Macedo Paulo Tarso Sanches Oliveira Mauro Antonio Homem Antunes Valdemir Lucio Durigon Elaine Cristina Cardoso Fidalgo daniel Fonseca de carvalho Agronomy-Soil Science Post Graduate Program Federal Rural University of Rio de JaneiroBR 465km 723897-000SeropedicaRJBrazil Federal University of Mato Grosso do Sul CxP.549Campo GrandeMS79070-900Brazil Federal Rural University of Rio de Janeiro Engineering DepartmentBR 465km 723897-000SeropedicaRJBrazil Technical College of the Federal Rural University of Rio de Janeiro BR 465km 723897-000SeropedicaRJBrazil National Center for Soil Research Brazilian Agricultural Research CorporationRio de JaneiroBrazil

We present a new approach for calculating the C-factor of RUSLE considering the effect of low-reflectance vegetation cover areas on the reduction of the effects on erosion caused by rainfall *** this,we propose the coefficients Cr2(rescaled 2)and C-PC(Precipitation Correction),which represent the Cfactor,and an adaptation in NDVI calculation,according to the seasonality of precipitation(NDVI-PC).The Cr2 factor is used when there is no seasonal effect of rainfall on vegetation,while the C-PC factor is calculated for localities under the influence of seasonality,from *** proposed approaches were tested using different satellites images in the Palmares-Ribeir~ao do Saco watershed,Rio de Janeiro,*** values of Cr2 and C-PC factors were compared to the Cr factor(rescaled)and to mean values from the literature for different land *** results indicated that the Cr2 factor represents an improvement in accuracy in relation to Cr by considering specific values of the studied area to normalize the data without ***,the C-PC factor is able to simulate the effect of seasonality,providing more realistics values of soil loss by the RUSLE as a function of the proportion of area affected by the rainfall seasonality obtained from *** conclude that both Cr2 and C-PC factors generate values similar of the C-factor observed in the literature,and therefore are able to provide better soil loss estimation than that using the Cr factor.

关键词： Soil erosion Land cover Soil use and management factor Vegetation seasonality NDVI

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Burn injury induces histopathological changes and cellproliferation in liver of rats

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World Journal of Hepatology 2016年第6期8卷 322-330页

作者： Jeferson Andre Bortolin Hananiah Tardivo Quintana Tabata de carvalho Tome Flavia Andressa Pidone Ribeiro daniel Araki Ribeiro Flavia de Oliveira department of Biosciences Federal University of São Paulo(UNIFESP)SantosSP 11060-001Brazil

AIM: To investigate effects of severe burn injury(BI) in rat liver through the histopathological and inflammatory markers analysis. METHODS: Forty-two male Wistar rats were distributed into two groups, control(C) and subjected to scald BI(SBI). The animals were euthanized one, four and 14 d post sham or 45% of the total body surface BI. Liver fragments were submitted to histopathological, morphoquantitative(hepatocyte area and cell density), ciclooxigenase-2(COX-2) immunoexpression, and gene expression [real-time polymerase chain reaction for tumor necrosis factor(TNF)-α, inducible nitric oxide synthase(i NOS) and caspase-3] methods. RESULTS: Histopathological findings showed inflammatory process in all periods investigated and hepatocyte degeneration added to increased amount of connective tissue 14 d post injury. Hepatocyte area, the density of binucleated hepatocytes and density of sinusoidal cells of SBI groups were increased when compared with control. COX-2 immunoexpression was stronger in SBI groups. No differences were found in TNF-α, i NOS and caspase-3 gene expression. CONCLUSION: BI induces histopathological changes, upregulation of COX-2 immunoexpression, and cell proliferation in liver of rats.

关键词： Burn injury Morphology Histophatology Liver Ciclooxigenase-2

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Special Issue on 15th Brazilian Polymer Conference:Biopolymers,Eco-Friendly and Biodegradable Polymers and Other Topics Related to Polymeric Materials derived from Renewable Materials

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Journal of Renewable Materials 2021年第4期9卷 599-600页

作者： Antonio Aprigio da Silva Curvelo Antonio José Felix carvalho daniel Pasquini São Carlos Institute of Chemistry University of São PauloSão Carlos13566-590-SPBrazil São Carlos School of Engineering University of São PauloSão Carlos13563-120-SPBrazil Institute of Chemistry Federal University of UberlândiaUberlândia38400-902MGBrazil

This issue of Journal of Renewable Materials is a special issue dedicated to the 15th Brazilian Polymer Conference(15th CBPol)which was held in Bento Gonçalves,Rio Grande do Sul State,Brazil,from 27 to 31 October,2019[1].CBPol is the main scientific forum in the field of polymer science and technology in *** conference has been held biannually since 1991 and in this event had almost 900 participants mainly from Brazil,but also from Argentina,Chile,Peru,USA,Canada,Belgium,France,Great Britain,Portugal and Spain,with 60%students and 40%professionals.A total of 1,100 papers from 2725 authors were presented,from which 25%(280 papers)was in the field of Biomaterials showing the importance of these materials which are in general based on renewable *** 280 works were developed mainly by researchers from Brazilian institutions(universities and research institutes),mainly from the south and southeast regions of the *** subject of more than 70%of the works was dedicated on vegetal raw materials,medicinal applications,packaging and composite materials.

关键词： materials showing annually

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