Pesquisa | SciELO

Abstract The objective of this study was to evaluate, through changes in the gills and livers of Sciades herzbergii, the environmental contamination to which estuarine organisms are exposed in two areas in São Marcos Bay - MA. Two collection areas located in São Marcos Bay were selected for this study: A1, an area close to the Port Complex, and A2, an area on Caranguejos Island (included in the Environmental Protection Area of Baixada Maranhense). Collections were carried out during rainy and dry periods. Sediments (for trace element analyses), surface water (for physico-chemical analyses), and specimens of S. herzbergii (for biometric measurements and identification of branchial and hepatic histopathology) were collected. Physico-chemical parameters (pH, dissolved oxygen, temperature and salinity) were within limits established by Brazilian legislation. Arsenic (in A1) and nickel (in A1 and A2) were above the legal standards in both periods. The highest percentage of histological alterations in the gills (aneurysms, lamellar fusion and detachment of the epithelium) occurred in the port area, in the rainy (93%) and dry (74%) periods. Liver alterations (melanomacrophage centers and necrosis) occurred only in specimens from the same area, in the rainy (41%) and dry (36%) periods. The highest histological indices of gill and liver changes were recorded in A1. This result was further supported by the total HI value of the lesions, which was higher in the port area compared to A2 (less impacted area), suggesting that the environmental conditions in that location are less favorable for the well-being of these organisms. Permanent environmental monitoring of the area is necessary to control environmental impacts efficiently.

Resumo O objetivo deste estudo foi avaliar, por meio de alterações nas brânquias e fígados de Sciades herzbergii, a contaminação ambiental a que os organismos estuarinos estão expostos em duas áreas da Baía de São Marcos - MA. Para este estudo foram selecionadas duas áreas de coleta localizadas na Baía de São Marcos: A1, área próxima ao Complexo Portuário, e A2, área na Ilha dos Caranguejos (incluída na Área de Proteção Ambiental da Baixada Maranhense). As coletas foram realizadas nos períodos chuvoso e seco. Foram coletados sedimentos (para análises de elementos traço), águas superficiais (para análises físico-químicas) e espécimes de S. herzbergii (para medidas biométricas e identificação de histopatologia branquial e hepática). Os parâmetros físico-químicos (pH, oxigênio dissolvido, temperatura e salinidade) estiveram dentro dos limites estabelecidos pela legislação brasileira. Arsênio (em A1) e níquel (em A1 e A2) estiveram acima dos padrões legais em ambos os períodos. A maior porcentagem de alterações histológicas nas brânquias (aneurismas, fusão lamelar e descolamento do epítélio) ocorreu na área portuária, nos períodos chuvoso (93%) e seco (74%). As alterações hepáticas (centros de melanomacrófagos e necrose) ocorreram apenas nos espécimes dessa mesma área, nos períodos chuvoso (41%) e seco (36%). Os maiores índices histológicos de alterações branquiais e hepáticas foram registrados em A1. Esse resultado foi ainda corroborado pelo valor de IH total das lesões, que foi maior na área portuária em comparação com A2 (área menos impactada), sugerindo que as condições ambientais naquele local são menos favoráveis ao bem-estar desses organismos. O monitoramento ambiental permanente da área é necessário para controlar os impactos ambientais de forma eficiente.

https://doi.org/10.1590/1519-6984.274069

PREDICTION OF THE GEOGRAPHIC DISTRIBUTION AND CONSERVATION OF AMAZONIAN PALM TREES Astrocaryum acaule MART. AND Astrocaryum aculeatum MART.
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Cordeiro, Adriel Lira

; Tomaz, Jennifer Souza

; Bezerra, Caroline de Souza

; Meneses, Carlos Henrique Salvino Gadêlha

; Aguiar, Ananda Virgínia de

; Wrege, Marcos Silveira

; Ramos, Santiago Linorio Ferreyra

; Lopes, Ricardo

; Fraxe, Therezinha de Jesus Pinto

; Lopes, Maria Teresa Gomes

Revista Árvore

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2023, Volume 47 elocation e4719

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

ABSTRACT Astrocaryum aculeatum Mart. Moreover, Astrocaryum acaule Mart. are palm trees with ecological and extractive importance in the Amazon. These are hearty species that have been associated with archaeological sites and thrive in the presence of humans in certain areas. This work aimed to verify the effect of global climate change on the potential geographic distribution of A. acaule and A. aculeatum in the current period and future climate scenarios using ecological niche modeling in Brazilian phytogeographic domains. The modeling was based on 19 bioclimatic variables obtained from the Worldclim website and four algorithms (Climate space model, Envelope Score, Niche Mosaic, and Environmental Distance). Additionally, the Environmental Distance algorithm showed greater similarity regarding species distribution with potential occurrence in the five Brazilian domains (Amazon, Pantanal, Caatinga, Cerrado, and Atlantic Forest). The dispersion patterns were very similar between the two Astrocaryum palms though A. aculeatum was more sensitive to climatic variations. A. acaule may be more resilient to changes, as demonstrated by being able to recolonize in the southern portion of the Amazon in future scenarios in the year 2070. The modeling helped to delimit potential areas for A. aculeatum and A. acaule, indicating the need for the conservation of the species in more sensitive regions.

RESUMO Astrocaryum aculeatum Mart. e Astrocaryum acaule Mart. são palmeiras que apresentam importância ecológica e para o extrativismo na Amazônia. São espécies rústicas e que foram associadas a sítios arqueológicos e à presença de humanos em determinadas áreas. O objetivo deste trabalho foi verificar o efeito das mudanças climáticas globais na distribuição geográfica potencial de A. acaule e A. aculeatum, no período atual e em cenários climáticos futuros, utilizando a modelagem de nicho ecológico nos domínios fitogeográficos brasileiros. As modelagens foram baseadas em 19 variáveis bioclimáticas, obtidas no site do Worldclim, e quatro algoritmos (Climate space model, Envelope Score, Niche Mosaic e Enviromental Distance), dos quais o algoritmo Environmental Distance apresentou maior similaridade quanto à distribuição das espécies com ocorrência potencial nos cinco domínios brasileiros (Amazônia, Pantanal, Caatinga, Cerrado e Mata Atlântica). Os padrões de dispersão foram muito similares entre as duas palmeiras de Astrocaryum, porém A. aculeatum é mais sensível às variações climáticas. A. acaule tem potencial para ser mais resiliente às mudanças, podendo recolonizar a porção sul da Amazônia em cenários futuros, no ano de 2070. A modelagem auxiliou a delimitar as áreas potenciais de A. aculeatum e A. acaule, indicando a necessidade de conservação das espécies em regiões mais sensíveis.

https://doi.org/10.1590/1806-908820230000019

Perception of entrepreneurs regarding public policies in fighting Covid-19
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Bezerra, Claudia M. S.

; Ramos, Heidy R.

; Bezerra, Eudes V.

; Teixeira, Marco A. C.

; Magalhães, Marcos F.

RAM. Revista de Administração Mackenzie

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2023, Volume 24 Nº 6 elocation eRAMD230068

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

Abstract Purpose: The research analyzed the perception of entrepreneurs in the cities of São Paulo and São Luis regarding if the public policies implemented during the pandemic were sufficient to face the Covid-19 crisis and how they contributed to the survival of micro, small and medium-sized enterprises (MSMEs), in adverse situations. Originality/value: Faced with the advance of the Covid-19 contagion curve, governments worldwide have adopted measures to contain the disease. Such efforts negatively impacted organizations, especially MSMEs, which are more susceptible to the effects of the crisis. In these situations, the role of the State in promoting public policies to face the crisis is fundamental. It can represent the difference between survival and recovery versus the closure of business activities. Design/methodology/approach: A qualitative research with an exploratory, descriptive approach was developed through an empirical study carried out in two stages, combining the answers of a questionnaire in Google Forms and interviews with 48 entrepreneurs from MSMEs in the cities of São Paulo and São Luís. Content analysis was supported by Atlas.ti software. Findings: Five categories of public policies were created: 1. financial, 2. tributaries, 3. operational, 4. politicians, and 5. health. In adverse situations, government support is essential for the survival and recovery of MSMEs. It was concluded that although the support policies have been considered insufficient by surveyed entrepreneurs, those who managed to gain access reported that they were essential for maintaining the business.

Resumo Objetivo: A pesquisa analisou a percepção dos empreendedores das cidades de São Paulo e São Luís em relação às políticas públicas implementadas durante a pandemia para o enfrentamento da crise da Covid-19 e como elas contribuíram para a sobrevivência das micro, pequenas e médias empresas (MPME) em situações adversas. Originalidade/valor: Ante o avanço da curva de contágio da Covid-19, os governos de todo o mundo adotaram medidas de contenção da doença. Tais medidas trouxeram impactos negativos para as organizações, em especial para as MPME, que são mais suscetíveis aos efeitos da crise. Nessas situações, o papel do Estado na promoção de políticas públicas de enfrentamento da crise é fundamental e pode representar a diferença entre a sobrevivência e recuperação e o encerramento das atividades do negócio. Design/metodologia/abordagem: Uma pesquisa qualitativa com abordagem exploratória de caráter descritivo foi desenvolvida por meio de um estudo empírico realizado em duas etapas, combinando as respostas de um questionário no Google Forms e entrevistas com 48 empreendedores de MPME nas cidades de São Paulo e São Luís. A análise de conteúdo foi apoiada pelo software Atlas.ti. Resultados: Cinco categorias de políticas públicas foram criadas: 1. financeiras, 2. tributárias, 3. operacionais, 4. políticas e 5. de saúde. Em situações adversas, o apoio governamental é fundamental para a sobrevivência e recuperação das MPME. Concluiu-se que, embora as políticas de apoio tenham sido consideradas insuficientes pelos empreendedores pesquisados, aqueles que conseguiram ter acesso relataram que elas foram fundamentais para a manutenção do negócio.

https://doi.org/10.1590/1678-6971/eramd230068.en

Screening for myeloid mutations in patients with myelodysplastic syndromes and AML with myelodysplasia-related changes
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Bezerra, Matheus F.

; Larrazábal, Bruna R.

; Lima, Aleide S.

; Mello, Mariana R.

; Pimentel, Raphael F.

; Weinhäuser, Isabel

; Costa, Fernando F.

; Fertrin, Kleber Y.

; Araújo, Aderson S.

; Machado, Cíntia G.

; Bezerra, Marcos A.

; Lucena-Araujo, Antonio R.

Hematology, Transfusion and Cell Therapy

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Set 2022, Volume 44 Nº 3 Páginas 328 - 331

Resumo: En | Texto: En | PDF: En

ABSTRACT Introduction: One of the most critical complications in myelodysplastic syndromes (MDS) is the progression to acute myeloid leukemia (AML). The dynamics of clonal evolution in MDS and how acquired mutations can be used as biomarkers to track disease progression remains under investigation. Objective and method: Herein, we investigated the frequency of common myeloid clonal mutations (FLT3, NPM1, JAK2, IDH1 and IDH2) in 88 patients with MDS and 35 AML patients with myelodysplasia-related changes, followed at a single reference center in northeastern Brazil. Results: Overall, 9/88 (10%) ofthe MDSpatients and 9/35 (26%) of the secondary AML patients had at least one mutation. While the JAK2 V617F mutation was the most frequent in the MDS patients, the FLT3, NPM1, IDH1 and IDH2 mutations were more frequently found in the secondary AML group. Furthermore, there was a higher frequency of FLT3, NPM1, IDH1 and IDH2 mutations in MDS patients classified as high-risk subtypes than in those of lower risk. Conclusion: Despite the limited sample size, our data suggest that mutations in FLT3, NPM1, IDH1 and IDH2 genes could be potential biomarkers to detect early disease progression in MDS.

https://doi.org/10.1016/j.htct.2020.10.967

EFFECTS OF ARTIFICIAL SHADING AND IRRIGATION WITH BRACKISH WATER ON THE INITIAL DEVELOPMENT OF Anadenanthera colubrina (Vell.) Brenan PLANTS
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Pinho, Luciana Luzia

; Lacerda, Claudivan Feitosa de

; Sousa, João Alencar de

; Santos, Alisson Moura

; Bezerra, Antônio Marcos Esmeraldo

; Cavalcante, Eduardo Santos

; Sales, Jonnathan Richeds da Silva

Revista Árvore

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2022, Volume 46 elocation e4607

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

RESUMO O uso de estratégias de manejo ou alterações no ambiente de cultivo podem reduzir os impactos da salinidade da água de irrigação sobre o desenvolvimento vegetal. Assim, nessa pesquisa foram avaliadas respostas fisiológicas, crescimento inicial e qualidade de plantas de Anadenanthera colubrina (Vell.) Brenan (Angico Branco) sob diferentes níveis de sombreamento e condutividade elétrica da água de irrigação, buscando-se identificar as condições mais favoráveis para o desenvolvimento dessa espécie utilizando-se águas salobras. O experimento foi realizado em blocos casualizados com parcelas subdivididas e quatro repetições. As parcelas foram formadas por quatro ambientes com diferentes níveis de sombreamento: 0 (pleno sol), 30, 50 e 70%, e as subparcelas, formadas por cinco níveis crescentes de condutividade elétrica da água de irrigação: 0,4, 1,6, 2,8, 4,0 e 5,2 dS.m−1. Foram avaliadas as variáveis: condutividade elétrica do substrato, trocas gasosas foliares, altura de plantas, produção de biomassa e índice de qualidade de Dickson aos 40 dias em viveiro. O uso do sombreamento artificial favoreceu o desenvolvimento das plantas e a taxa de fotossíntese, mesmo quando irrigadas com água de moderada e elevada salinidade. O IQD mostrou que as plantas de A. colubrina apresentaram maior índice de qualidade quando produzidas sob sombreamento intermediário (30% e 50%), com perdas no rendimento inferiores a 20% quando irrigadas com água com condutividade elétrica de até 2,8 dS.m−1.

ABSTRACT The use of management strategies or changes in the cultivation environment can reduce the impacts of irrigation water salinity on plant development. Therefore, in this research, physiological responses, initial growth, and plant quality of Anadenanthera colubrina (Vell.) Brenan (Angico Branco) were evaluated under different levels of shading and electrical conductivity of the irrigation water, seeking to identify the most favorable conditions for the development of this species using brackish water. The experiment was carried out in randomized blocks with split plots and four replications. The plots were formed by four environments with different shading levels: 0 (full sun), 30, 50, and 70%, and the subplots, formed by five increasing levels of electrical conductivity of the irrigation water: 0.4, 1.6, 2.8, 4.0, and 5.2 dS.m−1. The following variables were evaluated: substrate electrical conductivity, leaf gas exchange, plant height, biomass production, and Dickson quality index at 40 days in a nursery. The use of artificial shading favored plant development and photosynthesis rate, even when irrigated with moderate and high salinity water. The DQI showed that A. colubrina plants presented higher quality index when produced under intermediate shading (30% and 50%), with yield losses below 20% when irrigated with water with electrical conductivity up to 2.8 dS.m−1.

https://doi.org/10.1590/1806-908820220000007

Diretrizes da Sociedade Brasileira de Cardiologia sobre Angina Instável e Infarto Agudo do Miocárdio sem Supradesnível do Segmento ST – 2021
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Nicolau, José Carlos

; Feitosa Filho, Gilson Soares

; Petriz, João Luiz

; Furtado, Remo Holanda de Mendonça

; Précoma, Dalton Bertolim

; Lemke, Walmor

; Lopes, Renato Delascio

; Timerman, Ari

; Marin Neto, José A.

; Bezerra Neto, Luiz

; Gomes, Bruno Ferraz de Oliveira

; Santos, Eduardo Cavalcanti Lapa

; Piegas, Leopoldo Soares

; Soeiro, Alexandre de Matos

; Negri, Alexandre Jorge de Andrade

; Franci, Andre

; Markman Filho, Brivaldo

; Baccaro, Bruno Mendonça

; Montenegro, Carlos Eduardo Lucena

; Rochitte, Carlos Eduardo

; Barbosa, Carlos José Dornas Gonçalves

; Virgens, Cláudio Marcelo Bittencourt das

; Stefanini, Edson

; Manenti, Euler Roberto Fernandes

; Lima, Felipe Gallego

; Monteiro Júnior, Francisco das Chagas

; Correa Filho, Harry

; Pena, Henrique Patrus Mundim

; Pinto, Ibraim Masciarelli Francisco

; Falcão, João Luiz de Alencar Araripe

; Sena, Joberto Pinheiro

; Peixoto, José Maria

; Souza, Juliana Ascenção de

; Silva, Leonardo Sara da

; Maia, Lilia Nigro

; Ohe, Louis Nakayama

; Baracioli, Luciano Moreira

; Dallan, Luís Alberto de Oliveira

; Dallan, Luis Augusto Palma

; Mattos, Luiz Alberto Piva e

; Bodanese, Luiz Carlos

; Ritt, Luiz Eduardo Fonteles

; Canesin, Manoel Fernandes

; Rivas, Marcelo Bueno da Silva

; Franken, Marcelo

; Magalhães, Marcos José Gomes

; Oliveira Júnior, Múcio Tavares de

; Filgueiras Filho, Nivaldo Menezes

; Dutra, Oscar Pereira

; Coelho, Otávio Rizzi

; Leães, Paulo Ernesto

; Rossi, Paulo Roberto Ferreira

; Soares, Paulo Rogério

; Lemos Neto, Pedro Alves

; Farsky, Pedro Silvio

; Cavalcanti, Rafael Rebêlo C.

; Alves, Renato Jorge

; Kalil, Renato Abdala Karam

; Esporcatte, Roberto

; Marino, Roberto Luiz

; Giraldez, Roberto Rocha Corrêa Veiga

; Meneghelo, Romeu Sérgio

; Lima, Ronaldo de Souza Leão

; Ramos, Rui Fernando

; Falcão, Sandra Nivea dos Reis Saraiva

; Dalçóquio, Talia Falcão

; Lemke, Viviana de Mello Guzzo

; Chalela, William Azem

; Mathias Júnior, Wilson

Arquivos Brasileiros de Cardiologia

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Jul 2021, Volume 117 Nº 1 Páginas 181 - 264

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

https://doi.org/10.36660/abc.20210180 3052 downloads

Development of a Simple and Fast Procedure Based on Acid Dilution for Determination of Macro and Microelements in Guarana-Based Beverages by ICP OES
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Silva, Vinnícius Henrique C. da

; Silva Jr., André Luiz S. da

; Santos, Herick M.

; Lôbo, Ivon P.

; Bezerra, Marcos A.

; Jesus, Raildo M. de

Journal of the Brazilian Chemical Society

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Jul 2021, Volume 32 Nº 7 Páginas 1467 - 1475

Resumo: En | Texto: En | PDF: En

A simple analytical procedure is proposed for the direct analysis of guarana-based beverages in order to determine nutrient elements by inductively coupled plasma optical emission spectrometry (ICP OES). A Box-Behnken design, combined with Derringer’s desirability function, was applied to the simultaneous optimization of the ICP OES radiofrequency (RF), sample volume and nitric acid concentration. Using this approach, optimal conditions were established as RF power of 1.40 kW, and 5.0 mL of sample diluted twice with 0.5 mol L-1 HNO3. The optimized procedure allowed the determination of Cu, Fe, Mn, Zn, K, Ca, S, P and Mg with limits of quantification of 10.0, 2.0, 0.6, 6.0, 66.0, 65.0, 235, 40.0 and 20.0 µg L-1, respectively. Accuracy of the method was evaluated through analysis of water standard reference material (SRM NIST 1643f) and by addition-recovery experiments, in which satisfactory recoveries were obtained. The procedure was applied for the analysis of guarana-based soft and energy drinks. The concentration ranges (mg L-1) were: 0.36-43.3 (Ca), 4.04-192 (K), 0.36-44.8 (Mg), 10.1-1,073 (S), 0.04-92.4 (P), < 0.010-0.0174 (Cu), < 0.002-0.294 (Fe), < 0.006-0.06 (Zn) and < 0.0006-0.168 (Mn).

https://doi.org/10.21577/0103-5053.20210045 74 downloads

Development of a TD-NMR Method to Monitor Brazil Nuts Oil Content: A Green and Low-Cost Based Approach
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Ribeiro, Úrsula A.

; Queiroz, Leonardo C.

; Marassi, Agide G.

; Carvalho, André S.

; Barros, Gabriel A.

; Consalter, Daniel M.

; Bezerra, Jaqueline A.

; Santos, Alan D. C.

; Colnago, Luiz Alberto

; Machado, Marcos B.

Journal of the Brazilian Chemical Society

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Jul 2021, Volume 32 Nº 7 Páginas 1405 - 1412

Resumo: En | Texto: En | PDF: En

Growth in the international popularity of Brazil nuts oil (Bertholletia excelsa, Bonpl.) has demanded a closer look at quality aspects of the nuts. In this context, time-domain 1H nuclear magnetic resonance spectroscopy (TD-NMR) can be a useful tool for assessing the lipid portion of such matrices. In this work, a TD-NMR method was developed and validated to assess the oil content directly from Brazil nuts following the ISO 10565:1998 and DOQ-CGCRE-008. Full validation was addressed covering the working range from 0.67 to 25.00 g (coefficient of determination, R2= 0.9993). Limits of detection (LOD) and quantification (LOQ) were 0.20 and 0.67 g, respectively. The repeatability and intermediate precision assays met the guide requirements. Oil contents obtained in two laboratories (different equipment) were statistically similar (66.93 ± 4.69 and 70.13 ± 4.15%), highlighting the method’s robustness. The developed approach has the potential to be adopted as an industrial reference method for in situ monitoring of Brazil nuts oil contents.

https://doi.org/10.21577/0103-5053.20210039 105 downloads

Development of a Methodology Based on Extraction Induced by Emulsion Breaking for Copper Determination in Gasohol by Graphite Furnace Atomic Absorption Spectrometry
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Souza, Valdinei S. de

; Teixeira, Leonardo S. G.

; Korn, Maria G. A.

; Cerqueira, Uillian M. F. M.

; Bezerra, Marcos A.

Journal of the Brazilian Chemical Society

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Fev 2021, Volume 32 Nº 2 Páginas 329 - 336

Resumo: En | Texto: En | PDF: En

The development of a method based on extraction induced by emulsion breaking (EIEB) aiming copper determination in gasohol using graphite furnace atomic absorption spectrometry (GF AAS) is reported. Emulsification of the gasohol samples was carried out using nitric acid solution, (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol surfactant (Triton X-114), and ultrasound energy. The variables related to the extraction efficiency were optimized by multivariate approaches (two-level factorial fractional design and Doehlert design). The best results were obtained when the emulsion was formed with 5.0 mL of the sample, 0.200 mL of 2.4 mol L-1 HNO3, 0.100 mL of 10% Triton X-114 and 10 min of sonication. A fast and efficient emulsion breaking was performed at 90 ºC. A volume of 6.65 mL of the copper-rich hydroalcoholic phase was extracted, separated from the organic phase and analyzed. Under these conditions, the following analytical characteristics were obtained: 0.61 and 2.0 µg L-1 for limits of detection and quantification, respectively; precision (percentage of relative standard deviation, 10 µg L-1) of 2.8%; and analytical sensitivity of 0.011 L µg -1. Accuracy was assessed by spike tests, and values in the range of 95-110% were achieved. The method was applied in the determination of copper in Brazilian gasoline samples (gasohol with 27% ethanol).

https://doi.org/10.21577/0103-5053.20200183 219 downloads

10.

Mineral Nutrients and Plant-Fungal Interaction in Cocoa Trees (Theobroma cacao L.)
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Sousa Filho, Hélio R.

; Jesus, Raildo M. de

; Bezerra, Marcos A.

; Silva, Vinnícius H. C. da

; Silva Jr., André L. S. da

; Alves, Juscelia P. S.

; Santana, Gregório M.

; Souza Jr., José O. de

Journal of the Brazilian Chemical Society

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Fev 2021, Volume 32 Nº 2 Páginas 337 - 346

Resumo: En | Texto: En | PDF: En

An infection of the fungus Moniliophthora perniciosa in cocoa trees reduces productivity of the plant. In this study, the concentrations of mineral nutrients in healthy leaves and in leaves of vegetative broom of the cocoa plant were determined, and the relationship between the disease and the nutritional composition of the leaves was assessed. The samples were analyzed using the wet digestion method and the concentrations were determined by inductively coupled plasma optical emission spectrometry and the Kjeldahl method. Results indicate that leaves of vegetative broom have lower concentrations of Ca, Mg, S, Fe, Mn, and Ni than healthy leaves. Concentrations of P and Cu were lower in healthy leaves and higher in leaves of vegetative broom. In contrast, concentrations of K, N, and Zn were the same for both types of leaves. In short, plant-fungal interaction was reflected in the nutritional composition of the leaves, demonstrated by the differences in nutrient concentrations between healthy and infected leaf tissue.

https://doi.org/10.21577/0103-5053.20200184 351 downloads

11.

Digestive disorders associated with the consumption of palm fiber (Elaeis guineensis) in feedlot cattle
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Sarmento, Natalia Maxine F.P.

; Moura, Márcio Alan O.

; Cardoso, Rosekelly J.

; Lima, Adrielli Heloise A.

; Bezerra Junior, Pedro S.

; Duarte, Marcos D.

; Cerqueira, Valíria D.

; Riet-Correa, Gabriela

Pesquisa Veterinária Brasileira

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2021, Volume 41 elocation e06744

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

RESUMO: Alguns distúrbios digestivos em bovinos podem estar associados ao sistema de criação e alimentação dos animais. Entre estes estão à compactação de abomaso e a obstrução intestinal por fitobezoários, ambas relacionadas principalmente com a ingestão de alimentos com altos níveis de lignina e, consequentemente, de difícil digestibilidade. Neste trabalho são descritos os aspectos clínicos e patológicos de um surto de distúrbios digestivos em bovinos associados ao consumo de fibra de dendê (Elaeis guineensis). O surto acometeu um rebanho de 499 bovinos, criados em sistema de confinamento, após uma mudança na dieta que incluiu o aumento na quantidade de fibra de dendê. Após a mudança 40 animais (8,01%) apresentaram diarreia, distensão abdominal e regurgitação durante a ruminação e 21 animais (4,2%) morreram. Os bovinos examinados clinicamente apresentavam sinais de apatia, emagrecimento, desidratação, abdômen distendido, movimentos ruminais incompletos e ausentes, além de mucosas congestas. Três animais foram submetidos à necropsia e observou-se rúmen e reticulo distendidos e com grande quantidade de líquido acastanhado, fibras vegetais longas e emaranhadas e presença de areia e pedras. Em dois animais o omaso continha grande número de estruturas arredondadas medindo aproximadamente 5cm de diâmetro, constituídas de fibras vegetais (fitobezoários). No abomaso dos animais havia material semelhante ao do rúmen, sendo que um animal apresentou conteúdo compactado e um deles também tinha fitobezoários. Em dois animais foram observadas dilatação e obstrução total do lúmen do intestino delgado por fitobezoários. Durante o acompanhamento do abate de 76 bovinos, 15 (19,7%) apresentavam fitobezoários de diferentes tamanhos no abomaso e omaso. O aumento da quantidade de fibra de dendê na alimentação dos animais favoreceu a ocorrência de casos de compactação de abomaso e obstrução intestinal por fitobezoários, ocasionando perdas econômicas significativas.

ABSTRACT: Digestive disorders in cattle are associated with the breeding system and feed provided to the animals. Abomasal compaction is primarily related to the ingestion of forage with elevated levels of lignin, low quality, and difficult digestibility. In addition, the excess of fibrous food in the diet can lead to phytobezoars that may be responsible for intestinal obstruction disorders. This study aimed to describe pathological and clinical aspects of an outbreak of digestive disorders associated with the consumption of palm fiber (Elaeis guineensis). The outbreak struck a herd of 499 animals raised in a feedlot system after a change in diet that included an increase in the amount of palm fiber. Forty (8.01%) animals showed clinical signs such as fattening and regurgitation during rumination, and 21 (4.2%) animals died later. The cattle affected presented with apathy, emaciation, dehydration, distended abdomen, incomplete or absent ruminal movements, and congestive mucosa. Three animals were submitted to necropsy, and distended rumen and reticulum has a large amount of brownish liquid, long and tangled vegetable fibers with sand and stones. In two animals, the omasum had many rounded structures measuring approximately 5cm in diameter, made of vegetable fiber (phytobezoars). Abomasum of animals had similar material to the rumen, and one animal had compressed content. In two animals, dilatation was observed in the small intestine, and in the opening, the total obstruction of the lumen by phytobezoar was observed. During the follow-up of the slaughter of 76 cattle, 15 (19.7%) had phytobezoars of different sizes in the omasum and abomasum. The increased amount of oil palm fiber in animal feeding favored the occurrence of compression abomasum and intestinal obstruction phytobezoa, causing significant economic losses.

https://doi.org/10.1590/1678-5150-pvb-6744 61 downloads

12.

Concentration of Metals in Plant Litter Produced in Regions of Caatinga in Southwest Bahia, Brazil
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Lima, Joaly S. S. O.

; Gomes, Ivaldo S.

; Cerqueira, Uillian M. F. M.

; Carneiro, Paulo L. S.

; Sousa Filho, Hélio R.

; Jesus, Raildo M. de

; Bezerra, Marcos A.

Journal of the Brazilian Chemical Society

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Jul 2020, Volume 31 Nº 7 Páginas 1445 - 1452

Resumo: En | Texto: En | PDF: En

Plant litter has several functions in a forest ecosystem. Studies about plant litter are of great importance to better understand and conserve ecological environments. The objective of this study was to investigate the concentration of metals (Fe, Co, Ca, Cu, Ni, Mg, Mn and Zn) in Caatinga plant litter in the southwest region of Bahia. Plant litter was collected in summer (January/2017) and winter (August/2017). Concentrations were determined by flame atomic absorption spectrometry (FAAS). The results were submitted to multivariate analysis, principal component analysis (PCA), and hierarchical cluster analysis (HCA). The average amount of plant litter found in January and August was 1190 and 1329 kg ha-1, respectively. The twigs fraction provided the largest amount of biomass to the plant litter since this deposition occurred in greater quantity in August, a period of drought. Metal concentrations (g kg-1) in the analyzed samples ranged from 1.39-257 (Fe), < limit of quantification (LOQ)-0.269 (Co), 0.0036-0.61 (Cu), 1.39-8.76 (Ca), 0.0022-0.56 (Ni), 0.137-1.52 (Mg), 0.033-1.91 (Mn) and 0.0022-0.8 (Zn). The multivariate analysis showed that the composition of plant litter is altered seasonally.

https://doi.org/10.21577/0103-5053.20200029 206 downloads

13.

Determination of Copper and Cadmium in Petroleum Produced Formation Water by Electrothermal Atomic Absorption Spectrometry after Cloud Point Extraction
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Souza, Valdinei S.

; Teixeira, Leonardo S. G.

; Santos, Queila O.

; Gomes, Ivaldo S.

; Bezerra, Marcos A.

Journal of the Brazilian Chemical Society

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Jun 2020, Volume 31 Nº 6 Páginas 1186 - 1193

Resumo: En | Texto: En | PDF: En

Cloud point extraction (CPE) in association with graphite furnace atomic absorption spectrometry (GF AAS) was proposed for preconcentration and quantification of trace amounts of copper and cadmium in samples of saline produced formation water from petroleum exploration. The procedure was based on the formation of hydrophobic complexes of the analytes with 1,5-diphenylthiocarbazone (dithizone) in a micellar media of the surfactant (1,1,3,3-tetramethyl butyl) phenyl-polyethylene glycol (Triton X-114). Constrained mixture design was performed for the optimization of the proportions of the three solutions employed in the CPE: Triton X-114, dithizone, and buffer solution. Under the recommended conditions, the CPE GF AAS procedure allowed to obtain enrichment factors of 18 and 11 times, limits of quantification of 0.030 and 0.12 µg L-1 and precision, expressed as relative standard deviation (RSD, n = 8, 2.0 µg L-1), of 1.1 and 4.3% for copper and cadmium, respectively. The CPE GF AAS method was applied to the determination of copper and cadmium in samples of saline produced formation water from petroleum exploration, and its accuracy was accessed by analyzing certified reference material CASS-5 (Nearshore Seawater Reference Material for Trace Metals) from National Research Council (Canada).

https://doi.org/10.21577/0103-5053.20200004 242 downloads

14.

Use of Arduino in the Development of a New and Fast Automated Online Preconcentration System Based on Double-Knotted Reactor for the Mn Determination in Tea Samples by Flame Atomic Absorption Spectrometry (F AAS)
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Barreto, Jeferson A.

; Lemos, Valfredo A.

; Oliveira, Djalma M. de

; Cerqueira, Uillian Mozart F. M.

; Meira, Lucília A.

; Bezerra, Marcos A.

Journal of the Brazilian Chemical Society

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Jan 2020, Volume 31 Nº 1 Páginas 15 - 24

Resumo: En | Texto: En | PDF: En

In the present paper, an automated online preconcentration system based on the use of two knotted reactors (KR) was developed for Mn determination in tea samples by flame atomic absorption spectrometry (F AAS). The system automation was performed by using four solenoid valves to switch sample streams and reagents. Valves were driven electronically by an integrated Darlington transistor circuit and controlled by an open-source Arduino hardware platform written in C language. The preconcentration was based on the precipitation process of metal ions complexed with 2-(5-bromo-2-pyridylazo)-5-(diethylamino)phenol (5-Br-PADAP) on the inner walls of the reactor, followed by elution with a solution of hydrochloric acid. The optimized system allowed the Mn determination with limit of detection (LOD) of 2.1 mg L-1, precision (relative standard deviation (RSD), 50.0 mg L-1) of 2.6% and enrichment factors of 8. The system presented a sampling frequency of 60 h-1. The method accuracy was evaluated by analysis of the certified reference material (CRM) apple leaves (NIST 1515) and by addition/recovery tests obtaining recoveries between 95.2 to 119%. This method was applied in the Mn determination in commercial tea samples purchased from local trade. Manganese levels were found in a concentration range of 2.95 to 123 µg g-1.

https://doi.org/10.21577/0103-5053.20190118 541 downloads

15.

Characterization, fractionation and mobility of trace elements in surface sediments of the Jequiezinho River, Bahia, Brazil
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SILVA, DARCI S.

; CERQUEIRA, UILLIAM M.F.M.

; AGUIAR, ROSANE M.

; CARNEIRO, PAULO LUIS S.

; BEZERRA, MARCOS A.

Anais da Academia Brasileira de Ciências

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2020, Volume 92 Nº 3 elocation e20190558

Resumo: En | Texto: En | PDF: En

Abstract The Jequiezinho River is a temporary river. In the urban stretch it is impacted, with perennial flow coming from domestic sewage and rainwater. This study evaluated the geochemical distribution and potential mobility of some metals (Pb, Co, Ca, Cr, Mg, Cu, Fe, Mn, Ni and Zn) in sediments of the Jequiezinho River. Sediment samples were collected at ten different sites along the river. The silt/clay fraction was submitted to acid digestion and sequential extraction with analysis by FAAS. The results indicated that, in the more densely populated region, there was an increase in concentrations of Cr, Ni, Cu, Co, Pb, and Zn. The contents found were compared with the guideline values of TEL (Threshold Effect Levels) and PEL (Probable Effect Levels), not exceeding the maximum reference limits. The results indicated that Ca, Mg, Mn and Fe presented greater susceptibility to mobility and bioavailability suggesting the geochemical origin responsible for these high concentrations. The multivariate analysis showed that Cr, Ni, Cu, Co, Pb, and Zn presented a similar behavior, especially in locations with higher population density and the discharge of non-discriminated effluents, reflecting the anthropogenic contributions as responsible for the concentration increase.

https://doi.org/10.1590/0001-3765202020190558 460 downloads

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