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RESUMO: O girassol produz aquênios e óleo de qualidade, além de servir para produção de silagem, forragem e biodiesel. A modelagem de crescimento permite conhecer o padrão de crescimento da cultura e otimizar o manejo. O objetivo deste trabalho foi caracterizar o crescimento da cultivar de girassol Rhino por meio dos modelos Logístico e Gompertz e fazer considerações a respeito do manejo com base em pontos críticos. Os dados utilizados são oriundos de três ensaios de uniformidade com a cultivar de girassol confeiteiro Rhino, conduzidos na área experimental da Universidade Federal de Santa Maria, Campus Frederico Westphalen, na safra 2019/2020. Foram realizadas 14, 12 e 10 avaliações semanais de altura em 10 plantas, respectivamente, no primeiro, segundo e terceiro ensaio. Os dados foram ajustados em função da soma térmica acumulada. Os parâmetros foram estimados por meio do método dos mínimos quadrados ordinários, usando o algoritmo de Gauss-Newton. A qualidade de ajuste dos modelos aos dados foi medida pelo coeficiente de determinação ajustado, critério de determinação de Akaike, critério bayesiano de informação, e por meio da não linearidade intrínseca e paramétrica. Foram determinados os pontos de inflexão (IP), máxima aceleração (MAP), máxima desaceleração (MDP) e desaceleração assintótica (ADP). As análises estatísticas foram realizadas com Microsoft Office Excel® e o software R. Os modelos descreveram de forma satisfatória a curva de crescimento da altura do girassol, fornecendo parâmetros com interpretações práticas. O modelo Logístico apresenta melhor qualidade de ajuste, sendo o mais adequado para caracterização da curva de crescimento. Os pontos críticos estimados fornecem informações importantes para o manejo da cultura. As plantas daninhas devem ser controladas até o MAP. As aplicações de fertilizantes em cobertura devem ser realizadas entre MAP e IP. O ADP é um indicador de maturidade, após atingir este ponto, as plantas podem ser colhidas para a produção de silagem sem perda de volume e qualidade.

ABSTRACT: Sunflower produces achenes and oil of good quality, besides serving for production of silage, forage and biodiesel. Growth modeling allows knowing the growth pattern of the crop and optimizing the management. The research characterized the growth of the Rhino sunflower cultivar using the Logistic and Gompertz models and to make considerations regarding management based on critical points. The data used come from three uniformity trials with the Rhino confectionery sunflower cultivar carried out in the experimental area of the Federal University of Santa Maria - Campus Frederico Westphalen in the 2019/2020 agricultural harvest. In the first, second and third trials 14, 12 and 10 weekly height evaluations were performed on 10 plants, respectively. The data were adjusted for the thermal time accumulated. The parameters were estimated by ordinary least square’s method using the Gauss-Newton algorithm. The fitting quality of the models to the data was measured by the adjusted coefficient of determination, Akaike information criterion, Bayesian information criterion, and through intrinsic and parametric nonlinearity. The inflection points (IP), maximum acceleration (MAP), maximum deceleration (MDP) and asymptotic deceleration (ADP) were determined. Statistical analyses were performed with Microsoft Office Excel® and R software. The models satisfactorily described the height growth curve of sunflower, providing parameters with practical interpretations. The Logistics model has the best fitting quality, being the most suitable for characterizing the growth curve. The estimated critical points provide important information for crop management. Weeds must be controlled until the MAP. Covered fertilizer applications must be carried out between the MAP and IP range. ADP is an indicator of maturity, after reaching this point, the plants can be harvested for the production of silage without loss of volume and quality.

https://doi.org/10.1590/0103-8478cr20210213 99 downloads

Artificial neural networks and regression analysis for volume estimation in native species
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Amorim, Lucas M.

; Leite, Elton da S.

; Souza, Deoclides R. de

; Silva, Liniker F. da

; Mello, Carlos R. de

; Lima, José M. de

Revista Brasileira de Engenharia Agrícola e Ambiental

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aug 2021, Volume 25 N. 10 Pages 664 - 669

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

RESUMO O uso de modelos para estimar a produção florestal é uma importante ferramenta em áreas plantadas. Embora esse assunto tenha sido estudado em todo o mundo, ainda falta conhecimento a respeito da medição de volume para locais específicos, como os do Nordeste do Brasil. Desta forma, objetivou-se com este estudo avaliar o potencial de predição de redes neurais artificiais e regressão para a estimativa do volume de madeira em povoamentos homogêneos de Anadantera macrocarpa, Genipa americana e Mimosa caesalpiniflolia. Os métodos de regressão e de redes neurais artificiais (RNAs) mostraram-se aplicáveis para a estimativa do volume individual dos povoamentos em diferentes espaçamentos, aos sete anos de idade. O modelo de regressão de Spurr apresentou melhores resultados estatísticos e dispersão dos erros não tendenciosos para as espécies Anadantera macrocarpa e Genipa americana. Já o modelo de Shumacher-Hall foi mais preciso para a estimativa do volume da espécie Mimosa caesalpinifolia. As RNAs, com dois neurônios na camada intermediária, proporcionaram melhores ajustes para as três espécies, portanto, são recomendadas para estimar os volumes individuais das espécies avaliadas, por mostrar maior precisão, em relação à regressão, na estimativa do volume das espécies nativas avaliadas.

ABSTRACT Modeling is an important tool to estimate forest production in planted areas. Although this issue has been studied worldwide, knowledge regarding volume measurement in specific locations such as Northeast Brazil is still scarce. The present study aimed to evaluated the effectiveness of artificial neural networks (ANNs) and regression analysis in estimating the timber volume of homogeneous stands of Anadantera macrocarpa, Genipa americana, and Mimosa casalpinifolia, in order to better predict the growth and production of these species. Both methods were suitable for estimating the individual volume in 7-year-old stands with different spacing. The Spurr regression model showed better statistical results and dispersion of unbiased errors for Anadantera macrocarpa and Genipa americana, whereas the Shumacher-Hall model provided more accurate volume estimates for Mimosa caesalpinifolia. The ANNs calibrated with two neurons in the middle layer exhibited the best fit for all three species. As such, artificial neural networks can be recommended to estimate the individual volumes of the species analyzed in the study area.

https://doi.org/10.1590/1807-1929/agriambi.v25n10p664-669 2 downloads

The irrigation effect on nuts’ growth and yield of Carya illinoinensis
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MARCO, RUDINEI DE

; GOLDSCHMIDT, ROBERTO J.Z.

; HERTER, FLÁVIO G.

; MARTINS, CARLOS R.

; MELLO-FARIAS, PAULO C.

; UBERTI, ALISON

Anais da Academia Brasileira de Ciências

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2021, Volume 93 N. 1 elocation e20181351

Abstract: En | Text: En | PDF: En

Abstract Pecan trees require adequate soil moisture conditions to produce nuts with good yield and quality. Irrigation should be an important considered practice in orchards management plan, mainly in regions with water deficit periods. The objective of this research was to evaluate irrigation on pecan nuts growth and yield. This study was conducted in Uruguay, during the fast development phase until the pecan nuts harvest. Three irrigation treatments were used: 0 L (control), 70 L and 140 L plant-1 of water every two days, applied via drip irrigation in seven-year-old pecan trees of the cultivar Success. The number of nuts per cluster and nuts’ diameter and length were evaluated during nut growth. After harvesting, peeled nuts’ width and length were measured, and after peeling, the kernel length, width, height and filling and the kernel and peel percentage were evaluated. According to the results, it was possible to identify that periods of water deficit during pecan nuts development affected the kernel filling stageand size. Irrigation in pecan plants provides greater dimensions and nuts mass. With the use of 140 L plant-1, there was an increase in the nut mass of more than 100% in relation to the nuts from plants without irrigation.

https://doi.org/10.1590/0001-3765202120181351 425 downloads

Meteorological droughts in part of southeastern Brazil: Understanding the last 100 years
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SILVA, VINÍCIUS O.

; MELLO, CARLOS R.

Anais da Academia Brasileira de Ciências

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2021, Volume 93 elocation e20201130

Abstract: En | Text: En | PDF: En

Abstract Droughts have negatively influenced tropical regions on the planet with southeastern Brazil standing out. The objective of this study was to analyze droughts with different magnitudes since the ending of 19th and beginning of the 20th centuries based on the Standard Precipitation Index (SPI) and Standard Precipitation Evapotranspiration Index (SPEI), in the locations of São Paulo city (SP - city), metropolitan regions of Belo Horizonte (MR-BH) and Campinas (MR-Campinas), Lavras (South-MG), and Piracicaba (ME-SP). Two different periods were considered: i) wet period (SPI6 and SPEI6) and; ii) summer period (SPI4 and SPEI4). Considering the SPI indexes, the hydrological year of 2013/2014 was the driest observed for South-MG, ME-SP and MR-Campinas, while for MR-BH and SP-city, 1970/1971 and 1962/1963 were the driest, respectively. MR-BH and SP city showed different variability of 1970/1971 and 1962/1963, respectively. We could detect three periods with several consecutive droughts: 1908/1918; 1968/1981 and 2013/2019. Based on SPEI, the 2013/2014 hydrological year was the driest for all the regions, except for SP city, for which 1998/1999 and 1962/1963 were the driest, and MR-BH for which 1970/1971 and 2000/2001 were the driest. Precipitation might be the main factor to evaluate the occurrence of droughts in the studied locations, which indicates SPI is a satisfactory drought indicator for the region.

https://doi.org/10.1590/0001-3765202120201130 1 downloads

Mesophotic ecosystems at Fernando de Noronha Archipelago, Brazil (South-western Atlantic), reveal unique ichthyofauna and need for conservation
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Pimentel, Caio R.

; Rocha, Luiz A.

; Shepherd, Bart

; Phelps, Tyler A. Y.

; Joyeux, Jean-Christophe

; Martins, Agnaldo S.

; Stein, Carlos Eduardo

; Teixeira, João B.

; Gasparini, João Luiz

; Reis-Filho, José Amorim

; Garla, Ricardo C.

; Francini-Filho, Ronaldo B.

; Delfino, Stephanie D. T.

; Mello, Thayná J.

; Giarrizzo, Tommaso

; Pinheiro, Hudson T.

Neotropical Ichthyology

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2020, Volume 18 N. 4 elocation e200050

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

Resumo Apesar de muitos estudos sobre a ictiofauna do Arquipélago de Fernando de Noronha terem sido realizados, sua diversidade de peixes mesofóticos nunca foi estudada antes. Neste estudo utilizamos mergulho autônomo e mergulho técnico, vídeos subaquáticos remotos com isca e veículo operado remotamente para registrar peixes de ecossistemas rasos (≤ 30 m de profundidade) e mesofóticos (31 a 150 m de profundidade). Dezenove espécies de peixes pertencentes a 14 famílias são apresentadas aqui como novos registros, representando um aumento de 8,2% na riqueza de peixes marinhos da região, que agora possui um total de 250 espécies e 77 famílias. Esses novos registros incluem quatro prováveis novas espécies e reforçam a importância de estudos em ecossistemas mesofóticos. Nossos resultados também enfatizam a necessidade de proteção e atenção à essa ictiofauna única encontrada nesses ecossistemas profundos.

Abstract Although several studies on the ichthyofauna of the Fernando de Noronha Archipelago have been carried out, its mesophotic fish diversity has never been surveyed before. Here we used SCUBA and technical rebreather diving, baited remote underwater videos and remotely operated vehicle to record shallow (≤ 30 m depth) and mesophotic (31 to 150 m depth) fishes. Nineteen fish species belonging to 14 families are reported here as new records, representing an increase of 8.2% in marine fish richness for the region, which now has a total of 250 species and 77 families. These new records include four potential new species and highlight the importance of surveying mesophotic ecosystems, even in well studied sites. Our results also emphasize the need for protection and attention to the unique ichthyofauna found at mesophotic depths.

https://doi.org/10.1590/1982-0224-2020-0050 1657 downloads

Channel Characteristics for Fixed and Portable DTV Reception in a Single Frequency Network
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Guerra, Maurício V.

; Filho, Jair L. de A.

; Ron, Carlos V. Rodriguez

; Mello, Luiz A. R. da Silva

; Castellanos, Pedro V. G.

Journal of Microwaves, Optoelectronics and Electromagnetic Applications

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jul 2019, Volume 18 N. 3 Pages 439 - 451

Abstract: En | Text: En | PDF: En

Abstract This paper presents the propagation channel characteristics of a digital TV single-frequency network (SFN) obtained by carrying out field measurements using two synchronized transmitters. The measurements are performed at 31 reception points using both a directive reception antenna, which is typical of fixed reception scenarios, and an omnidirectional antenna, which is used to receive mobile signals. The characteristic parameters of the channel are obtained, including the average delay, the root mean square (RMS) delay spread, and the Rician K-factor, which are important for the design of SFN systems. An empirical expression is obtained for the prediction of the RMS delay spread as a function of the K factor and the distances to the transmission antennas.

https://doi.org/10.1590/2179-10742019v18i31778 760 downloads

Characterization and in silico Mutagenic Assessment of a New Betahistine Degradation Impurity
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Mello, Murilo B. M. de

; Oliveira, Antonio A. F. de

; Oliveira, Caroline L. de

; Ultramari, Mariah A.

; Gama, Fernando H. S.

; Mascarello, Alessandra

; Guimarães, Cristiano R. W.

; Freitas, Miller N. de

; Cunha, Carlos E.

; Lourenço, Tiago C.

; Ferreira, Fernanda P.

; Lopes, João L. C.

; Clososki, Giuliano C.

Journal of the Brazilian Chemical Society

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jul 2019, Volume 30 N. 7 Pages 1415 - 1424

Abstract: En | Text: En | PDF: En

Currently, the pharmaceutical industry devotes great attention to drug degradation products because these compounds can offer risks to patients. A previous degradation study of betahistine (N-α-methyl-2-pyridylethylamine) conducted under different stress conditions detected three main impurities named A, B and C. Degradation products were analyzed by high-resolution mass spectrometry in electrospray source and time of flight analyzer (ESI-TOF) and nuclear magnetic resonance (NMR). Impurity mutagenicity was evaluated by Derek Nexus and Sarah Nexus softwares. Liquid chromatography hyphenate with tandem mass spectrometry (LC-MS/MS) analysis of the betahistine forced degradation sample indicated the presence of a new impurity, which was named impurity C1. 2D NMR experiments allowed the complete structural characterization of the new entity. The active pharmaceutical ingredient and degradation impurities were classified as inactive in the in silico mutagenic studies. Systematic investigation of a forced degradation sample led to the characterization of a new betahistine impurity. The in silico mutagenicity study of the betahistine degradation impurities may be useful in the risk assessment of the drug products.

https://doi.org/10.21577/0103-5053.20190037 853 downloads

SPATIALIZATION OF THE ANNUAL MAXIMUM DAILY RAINFALL IN SOUTHEASTERN BRAZIL
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Batista, Marcelo L.

; Coelho, Gilberto

; Mello, Carlos R. de

; Oliveira, Marcelo S. de

Engenharia Agrícola

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feb 2019, Volume 39 N. 1 Pages 97 - 109

Abstract: En | Text: En | PDF: En

ABSTRACT Extreme rainfall can lead to heavy damage and losses, such as landslides, floods and agricultural productivity as well as the loss of human and animal lives. To mitigate these losses, water resources management policies are needed, among other goals, to study and predict the frequency of such events in a given region to minimize their harmful effects. The present study investigated the Generalized Extreme Value (GEV) probability distribution applied to the annual maximum daily precipitation data from rainfall stations in the southeastern Brazil. A total of 1,921 rainfall stations were considered, among which the stations with at least 15 years of uninterrupted observations were selected. Subsequently, the stationarity and adherence were tested. GEV probability distribution parameters were then estimated. The results enabled satisfactory spatial interpolation by ordinary kriging and the generation of maps of the distribution parameters. The semivariogram model with the best fit to the three GEV distribution parameters was the exponential model.

https://doi.org/10.1590/1809-4430-eng.agric.v39n1p97-109/2019 825 downloads

Prevalence, treatment, and control of dyslipidemia in diabetic participants of two brazilian cohorts: a place far from heaven
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Martins, Nestor S.

; Mello, Daniel S.S.

; Barreto, Joaquim

; Soares, Alexandre A.S.

; Breder, Ikaro

; Cunha, Jessica

; Nadruz, Wilson

; Coelho Filho, Otavio R.

; Matos-Souza, José Roberto

; Coelho, Otavio R.

; Munhoz, Daniel B.

; Silva, José Carlos Quinaglia e

; Sposito, Andrei C.

; Carvalho, Luiz Sergio F

Revista da Associação Médica Brasileira

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jan 2019, Volume 65 N. 1 Pages 3 - 8

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

RESUMO OBJETIVO O diabetes é importante causa de mortalidade cardiovascular. Nos últimos anos, a mortalidade diminuiu substancialmente, mais em diabéticos do que em não diabéticos, em grande parte devido ao controle de outros fatores de risco cardiovasculares. Nosso estudo tem como objetivo analisar o controle de dislipidemia em duas coortes de diabéticos. MÉTODOS Foram estudados pacientes de duas coortes distintas, sendo 173 pacientes do BHS (Brasília Heart Study) e 222 pacientes do BDS (Brazilian Diabetes Study). Os dados sobre controle de dislipidemia foram estudados nas duas populações diferentes. Todos os pacientes eram diabéticos. RESULTADOS Há diferenças significativas em relação às comorbidades entre os grupos de LDL-C no BDS. A média de hemoglobina glicada é de 8,2 no grupo com LDL-C > 100, comparado com 7,7 e 7,5 nos grupos 70-100 e < 70, respectivamente (p = 0,024). Há maior porcentagem de pacientes hipertensos com LDL entre 70-100 (63,9%), quando comparado aos grupos < 70 e > 100 (54,3% e 54,9%, respectivamente; p = 0,005). A pressão diastólica é mais elevada no grupo com LDL > 100, com média de 87 mmHg, comparado com 82,6 mmHg e 81,9 mmHg nos grupos 70-100 e < 70, respectivamente (p = 0,019). O grupo com LDL > 100 tem maior porcentagem de tabagistas (8,7%) quando comparado aos grupos com LDL entre 70-100 e < 70 (5,6% e 4,3%, respectivamente; p = 0,015). Há, também, diferença na incidência prévia de coronariopatia. No grupo com LDL < 70, 28,3% dos pacientes já apresentaram infarto prévio, comparados com 11,1% e 10,6% nos grupos 70-100 e > 100, respectivamente (p < 0,001). CONCLUSÃO Os dados do nosso estudo mostram que o controle de dislipidemia em diabéticos é inadequado, e há uma tendência de associação direta entre descontrole glicêmico e descontrole de dislipidemia, além de associação com outros fatores de risco cardiovascular, como hipertensão diastólica e tabagismo. Esse pior controle pode estar relacionado ao platô no descenso da curva de mortalidade, e o investimento nesse quesito pode melhorar a saúde cardiovascular dos diabéticos.

SUMMARY OBJECTIVE Diabetes is one of the leading causes of cardiovascular mortality. Over the last years, mortality has decreased significantly, more in individuals with diabetes than in healthy ones. That is mostly due to the control of other cardiovascular risk factors. The objective of our study was to analyze the dyslipidemia control in two diabetes cohorts. METHODS Patients from two distinct cohorts were studied, 173 patients from the BHS (Brasília Heart Study) and 222 patients from the BDS (Brazilian Diabetes Study). The data on dyslipidemia control were studied in both different populations. All patients had diabetes. RESULTS There are significant differences concerning comorbidities between the LDL-C and BDS groups. The average glycated hemoglobin is of 8.2 in the LDL-C > 100 group in comparison with 7.7 and 7.5 in the 70-100 and < 70 groups, respectively (p = 0.024). There is a higher percentage of hypertensive patients with LDL between 70-100 (63.9%), when comparing the < 70 and > 100 groups (54.3% and 54.9%, respectively; p = 0.005). Diastolic pressure is higher in the group with LDL > 100, with an average of 87 mmHg, in comparison with 82.6 mmHg and 81.9 mmHg in the 70-100 and < 70 groups, respectively (p = 0.019). The group with LDL > 100 has the greatest percentage of smokers (8.7%) in comparison with the groups with LDL between 70-100 and < 70 (5.6% and 4.3%, respectively; p = 0.015). There is also a difference in the previous incidence of coronaropathy. In the group with LDL < 70, 28.3% of patients had already experienced a previous infarction, compared with 11.1% and 10.6% in the 70-100 and > 100 groups, respectively (p < 0.001). CONCLUSIONS The data in our study have shown that the dyslipidemia control in diabetic patients is inadequate and there is a tendency of direct association between lack of blood glucose control and lack of dyslipidemia control, in addition to the association with other cardiovascular risk factors, such as diastolic hypertension and smoking. This worsened control might be related to the plateau in the descending curve of mortality, and investments in this regard can improve the cardiovascular health in diabetic patients.

https://doi.org/10.1590/1806-9282.65.1.3 1478 downloads

10.

Spatial distribution of wood volume in Brazilian savannas
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SILVEIRA, EDUARDA M.O.

; REIS, ALINY A. DOS

; TERRA, MARCELA C.N.S.

; WITHEY, KIERAN D.

; MELLO, JOSÉ M. DE

; ACERBI-JÚNIOR, FAUSTO W.

; FERRAZ FILHO, ANTONIO CARLOS

; MELLO, CARLOS R.

Anais da Academia Brasileira de Ciências

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2019, Volume 91 N. 4 elocation e20180666

Abstract: En | Text: En | PDF: En

Abstract: Here we model and describe the wood volume of Cerrado Sensu Stricto, a highly heterogeneous vegetation type in the Savanna biome, in the state of Minas Gerais, Brazil, integrating forest inventory data with spatial-environmental variables, multivariate regression, and regression kriging. Our study contributes to a better understanding of the factors that affect the spatial distribution of the wood volume of this vegetation type as well as allowing better representation of the spatial heterogeneity of this biome. Wood volume estimates were obtained through regression models using different environmental variables as independent variables. Using the best fitted model, spatial analysis of the residuals was carried out by selecting a semivariogram model for generating an ordinary kriging map, which in turn was used with the fitted regression model in the regression kriging technique. Seasonality of both temperature and precipitation, along with the density of deforestation, explained the variations of wood volume throughout Minas Gerais. The spatial distribution of predicted wood volume of Cerrado Sensu Stricto in Minas Gerais revealed the high variability of this variable (15.32 to 98.38 m3 ha-1) and the decreasing gradient in the southeast-northwest direction.

https://doi.org/10.1590/0001-3765201920180666 1279 downloads

11.

1º Posicionamento Brasileiro sobre o Impacto dos Distúrbios de Sono nas Doenças Cardiovasculares da Sociedade Brasileira de Cardiologia
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Drager, Luciano F.

; Lorenzi-Filho, Geraldo

; Cintra, Fatima Dumas

; Pedrosa, Rodrigo P.

; Bittencourt, Lia R. A.

; Poyares, Dalva

; Carvalho, Carolina Gonzaga

; Moura, Sonia Maria Guimarães Pereira Togeiro

; Santos-Silva, Rogerio

; Bruin, Pedro F. C. de

; Geovanini, Glaucylara R.

; Albuquerque, Felipe N.

; Oliveira, Wercules Antonio Alves de

; Moreira, Gustavo A.

; Ueno, Linda Massako

; Nerbass, Flávia Baggio

; Rondon, Maria Urbana Pinto Brandão

; Barbosa, Eline Rozária Ferreira

; Bertolami, Adriana

; Paola, Angelo Amato Vincenzo de

; Marques, Betânia Braga Silva

; Rizzi, Camila Futado

; Negrão, Carlos Eduardo

; Uchôa, Carlos Henrique Gomes

; Maki-Nunes, Cristiane

; Martinez, Denis

; Fernández, Edmundo Arteaga

; Maroja, Fabrizio U.

; Almeida, Fernanda R.

; Trombetta, Ivani C.

; Storti, Luciana J.

; Bortolotto, Luiz Aparecido

; Mello, Marco Túlio de

; Borges, Melania Aparecida

; Andersen, Monica Levy

; Portilho, Natanael de Paula

; Macedo, Paula

; Alves, Rosana

; Tufik, Sergio

; Fagondes, Simone C.

; Risso, Thaís Telles

Arquivos Brasileiros de Cardiologia

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aug 2018, Volume 111 N. 2 Pages 290 - 340

Abstract: Pt | Text: Pt | PDF: Pt

https://doi.org/10.5935/abc.20180154 8719 downloads

12.

Geomorphology-based unit hydrograph models for flood risk management: case study in Brazilian watersheds with contrasting physiographic characteristics
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BESKOW, SAMUEL

; NUNES, GABRIELA S.

; MELLO, CARLOS R. DE

; CALDEIRA, TAMARA L.

; NORTON, LLOYD D.

; STEINMETZ, ALICE A.

; VARGAS, MARCELLE M.

; ÁVILA, LÉO F.

Anais da Academia Brasileira de Ciências

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apr 2018, Volume 90 N. 2 Pages 1873 - 1890

Abstract: En | Text: En | PDF: En

ABSTRACT Heavy rainfall in conjunction with an increase in population and intensification of agricultural activities have resulted in countless problems related to flooding in watersheds. Among the techniques available for direct surface runoff (DSR) modeling and flood risk management are the Unit Hydrograph (UH) and Instantaneous Unit Hydrograph (IUH). This study focuses on the evaluation of predictive capability of two conceptual IUH models (Nash and Clark), considering their original (NIUH and CIUH) and geomorphological approaches (NIUHGEO and CIUHGEO), and their advantages over two traditional synthetics UH models - Triangular (TUH) and Dimensionless (DUH), to estimate DSR hydrographs taking as reference two Brazilian watersheds with contrasting geomorphological and climatic characteristics. The main results and conclusions were: i) there was an impact of the differences in physiographical characteristics between watersheds, especially those parameters associated with soil; the dominant rainfall patterns in each watershed had an influence on flood modeling; and ii) CIUH was the most satisfactory model for both watersheds, followed by NIUH, and both models had substantial superiority over synthetic models traditionally employed; iii) although geomorphological approaches for IUH had performances slightly better than TUH and DUH, they should not be considered as standard tools for flood modeling in these watersheds.

https://doi.org/10.1590/0001-3765201820170430 2057 downloads

13.

Human-modified landscape acts as refuge for mammals in Atlantic Forest
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Bovo, Alex Augusto de Abreu

; Magioli, Marcelo

; Percequillo, Alexandre Reis

; Kruszynski, Cecilia

; Alberici, Vinicius

; Mello, Marco A. R.

; Correa, Lidiani Silva

; Gebin, João Carlos Zecchini

; Ribeiro, Yuri Geraldo Gomes

; Costa, Francisco Borges

; Ramos, Vanessa Nascimento

; Benatti, Hector Ribeiro

; Lopes, Beatriz

; Martins, Maísa Z. A.

; Diniz-Reis, Thais Rovere

; Camargo, Plínio Barbosa de

; Labruna, Marcelo Bahia

; Ferraz, Katia Maria Paschoaletto Micchi de Barros

Biota Neotropica

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2018, Volume 18 N. 2 elocation e20170395

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

Resumo: Paisagens antropicamente modificadas (HMLs) são compostas por fragmentos florestais pequenos, isolados e defaunados, imersos em áreas agrícolas e/ou urbanas. Informações sobre as espécies que habitam essas paisagens são importantes para o direcionamento de estratégias de conservação em escalas local e regional. Uma vez que as HMLs são as paisagens dominantes na Mata Atlântica, o objetivo deste trabalho foi avaliar a diversidade de mamíferos em uma HML do sudeste do Brasil e propor estratégias para sua conservação. Foram coletados dados de mamíferos terrestres (pequenos, médios e grandes) e voadores em três fragmentos florestais (10, 14 e 26 ha) e áreas adjacentes, entre 2003 e 2016, usando métodos complementares: busca ativa, armadilhamento fotográfico, armadilhas de captura e redes de neblina. Adicionalmente, foram utilizados dados de literatura para complementar a lista de espécies. Foram registradas 35 espécies de mamíferos nativos (6 de pequenos, 16 de médios e grandes e 13 de morcegos) e sete espécies exóticas. A assembleia de mamíferos registrada (terrestres e voadores), embora composta por espécies generalistas, apresentou três espécies de médio e grande porte ameaçadas de extinção nacionalmente (Leopardus guttulus, Puma concolor and Puma yagouaroundi) e duas deficientes em dados (Galictis cuja and Histiotus velatus), destacando a importância dessa HML para conservação e manutenção das populações de mamíferos. Embora inserida em uma paisagem extremamente modificada, a área de estudo abriga uma riqueza significativa de mamíferos de médio e grande porte, sendo um importante refúgio para a biodiversidade na região. Entretanto, essa biodiversidade está ameaçada pela baixa qualidade dos habitats, por atropelamentos e por abundantes populações de cães e gatos domésticos. Portanto, enfatizamos a necessidade de estratégias de conservação focadas nos mamíferos de médio e grande porte como grupo "guarda-chuva", o que pode beneficiar as demais espécies na paisagem. Recomendamos ações de conservação visando a restauração biológica, para melhorar a composição estrutural e conectividade dos fragmentos florestais, reduzir o número de atropelamentos e controlar as populações de cães e gatos domésticos, afim de manter e aumentar a diversidade local de mamíferos em longo prazo.

Abstract: Human-modified landscapes (HMLs) are composed by small, isolated and defaunated forest fragments, which are surrounded by agricultural and urban areas. Information on species that thrives in these HMLs is essential to direct conservation strategies in local and regional scales. Since HMLs are dominant in the Atlantic Forest, we aimed to assess the mammalian diversity in a HML in southeastern Brazil and to propose conservation strategies. We collected data of terrestrial (small-, medium- and large-sized) and volant mammals in three small forest fragments (10, 14 and 26 ha) and adjacent areas, between 2003 and 2016, using complementary methods: active search, camera trapping, live-traps, mist nets and occasional records (i.e., roadkills). In addition, we used secondary data to complement our species list. We recorded 35 native mammal species (6 small-sized, 16 medium- and large-sized, and 13 bats) and seven exotic species in the HML. The recorded mammal assemblage (non-volant and volant), although mainly composed of common and generalist species, includes three medium- and large-sized species nationally threatened (Leopardus guttulus, Puma concolor and Puma yagouaroundi) and two data deficient species (Galictis cuja and Histiotus velatus), highlighting the importance of this HML for the maintenance and conservation of mammal populations. Despite highly impacted by anthropogenic disturbances, the study area harbors a significant richness of medium- and large-sized mammals, being an important biodiversity refuge in the region. However, this biodiversity is threatened by the low quality of the habitats, roadkills and abundant populations of domestic cats and dogs. Therefore, we stress the need of conservation strategies focusing on the medium- and large-sized mammals as an umbrella group, which could benefit all biodiversity in the landscape. We recommend actions that promotes biological restoration, aiming to increase structural composition and connectivity of the forest fragments, reducing roadkills and controlling the domestic cats and dogs' populations, in order to maintain and improve the diversity of mammals in long-term.

https://doi.org/10.1590/1676-0611-bn-2017-0395 3596 downloads

14.

Eventos extremos de precipitação no Alto Rio Grande, MG: Análise probabilística
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Junqueira Júnior, José A.

; Mello, Carlos R. de

; Alves, Geovane J.

Revista Brasileira de Engenharia Agrícola e Ambiental

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apr 2015, Volume 19 N. 4 Pages 301 - 308

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

As distribuições de probabilidades de valores extremos desempenham importante papel na modelagem de eventos extremos. Elas têm sido amplamente aplicadas em estudos hidrológicos a fim de predizer, para um nível de confiança, valores esperados num dado tempo de retorno. Várias distribuições têm sido empregadas com diferentes métodos de ajuste. Objetivou-se neste trabalho verificar a aderência das distribuições GEV e Gumbel aos dados de precipitação diária máxima anual de doze estações pluviométricas no Alto Rio Grande, MG. Foram consideradas três sub-regiões com características fisiográficas peculiares, cada uma com quatro estações pluviométricas em seus domínios, Planalto Campos das Vertentes (PCV), Serra da Mantiqueira (SM) e uma sub-região de Transição (TR) entre as duas. Para a estimação dos parâmetros utilizou-se o método dos momentos, máxima verossimilhança e momentos-L. A aderência dos ajustes foi avaliada pelos testes de Filliben e Qui-quadrado (χ2). A metodologia dos momentos-L mostrou-se como a melhor opção, independente da sub-região sendo que se recomenda, para as sub-regiões SM e TR, a distribuição Gumbel, enquanto para o PCV a melhor opção de ajuste é a GEV.

Probabilistic models have played an important role for stochastic modeling of the extreme events. They have been widely used in hydrological studies to predict, for a confidence level, expected values in a given return period. Several probabilistic models have been applied based on different adjustment methods which estimate the statistical moments of them. The aim of this study was to verify the adherence of Generalized Extreme Values (GEV) and Gumbel probabilistic models at two frequency of occurrence of heavy rainfall events in the Upper Rio Grande region (UGR), Southern Minas Gerais. UGR region was divided into three sub-regions with similar physiographic features in which four rain-gauging stations were studied: Plateau of Campos das Vertentes (PCV), Mantiqueira Range (SM) and a transition sub-region (TR). For estimating the distribution parameters, the Moment Method, Maximum Likelihood and L-moments were tested. The adherence of probabilistic models was evaluated by both Filiben and Chi-square tests. L-moments method showed to be the best method for all sub-regions and models. In addition, for the SM and TR sub-regions Gumbel model produced better results while for the PCV, GEV model was more appropriate.

https://doi.org/10.1590/1807-1929/agriambi.v19n4p301-308 1381 downloads

15.

Modelagem probabilística de eventos de precipitação extrema no estado do Rio Grande do Sul
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Caldeira, Tamara L.

; Beskow, Samuel

; Mello, Carlos R. de

; Faria, Lessandro C.

; Souza, Mayara R. de

; Guedes, Hugo A. S.

Revista Brasileira de Engenharia Agrícola e Ambiental

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mar 2015, Volume 19 N. 3 Pages 197 - 203

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

A gestão de cheias em bacias hidrográficas brasileiras deve ser discutida e priorizada, porém o cenário atual indica lacunas quanto às informações hidrológicas com variabilidade espacial e temporal condizentes. A modelagem probabilística de eventos extremos de precipitação, buscando a extrapolação para uma frequência e duração, pode servir como excelente ferramenta de análise e tomada de decisões. O objetivo principal deste trabalho foi analisar o ajuste de diferentes modelos probabilísticos a séries de precipitação máxima diária anual no Rio Grande do Sul. Séries pluviométricas de 342 estações foram ajustadas às distribuições Log-Normal a 2 e 3 parâmetros e Gumbel e a adequação foi realizada pelos testes de Kolmogorov-Smirnov e Qui-Quadrado. Todas as distribuições de probabilidade consideradas foram adequadas; entretanto, a distribuição Log-Normal a 3 parâmetros apresentou os melhores ajustes segundo os resultados do teste Qui-Quadrado. Os parâmetros das distribuições de probabilidades apresentaram variabilidade ao longo do estado e forte relação com a localização, sugerindo que a regionalização de chuvas intensas pode ser empregada no Rio Grande do Sul como excelente ferramenta de gestão.

Flood management in Brazilian watersheds must be discussed and prioritized, however, the current scenario indicates that there are gaps in hydrological information with respect to its spatial and temporal variability. The probabilistic modelling of extreme rainfall events, having as goal to extrapolate values for a given frequency and duration, can be used as an excellent tool for analysis and decision-making. The main objective of this study was to analyse the adjustment of different probabilistic models for series of annual maximum daily rainfall in Rio Grande do Sul. Series of 342 rain gauges were adjusted to 2-parameter Log-Normal, 3-parameter Log-Normal and Gumbel probability distributions and goodness-of-fit tests were based on the Kolmogorov-Smirnov and Chi-Square procedures. It was found that all the distributions presented adequate results, however, 3-parameter Log-Normal distribution had the best performance in accordance with the Chi-Square test. The parameters of probability distribution presented variability over the state and a pronounced relationship with the location of rain gauges. This suggests that regionalization of high-intensity rainfall can be employed in Rio Grande do Sul as an excellent management tool.

https://doi.org/10.1590/1807-1929/agriambi.v19n3p197-203 2503 downloads

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