Pesquisa | SciELO

Research to identify plant bioactive compounds led to the evolution of extraction methods. This study optimized ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) to extract the flavonoids of Croton grewioides Baill. species contributing to characterize the polar extract profile and understand the antioxidant potential of these plant constituents. The use of experimental design and statistical treatments enabled the determination of the ideal conditions for each technique. The extracts of five accessions of C. grewioides were obtained under the optimized extraction conditions and were analyzed using ultra high-resolution mass spectrometry (FT-Orbitrap MS) operating at negative ionization mode for flavonoids detection. The accurate experimental mass obtained to the main compounds was used to attribute the molecular formula. Chemical structures of the main compounds detected were proposed using structure data bases. Chemometric analysis were performed with two FT-Orbitrap MS spectra samples using the identified metabolites and, the antioxidant activity data, showing that for this species the MAE was most effective in extracting the antioxidant compounds. It was possible to propose the structures for forty compounds in the C. grewioides extracts, demonstrating the excellent performance of the FT-Orbitrap MS in providing information on the chemical profile of polar compounds in plant extracts. methods ultrasoundassisted ultrasound assisted UAE (UAE microwaveassisted microwave (MAE Baill constituents technique C highresolution high resolution FTOrbitrap FT Orbitrap detection formula bases

https://doi.org/10.21577/0103-5053.20230004

Resistance determinants of emerging pathogens isolated from an intensive care unit as a parameter of population health conditions of the Legal Amazon microregion
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Deusdará, T. T.

; Felix, M. K. C.

; Brito, H. S.

; Ribeiro, D. R.

; Cangussu, E. W. S.

; Albuquerque, B.

; Santos, G. R.

; Chaves, J. R.

; Carvalho, W. C. R.

; Astolfi-Filho, S.

; Assunção, E. N.

; Mariúba, L. A. M.

; Nogueira, P. A.

; Viana, K. F.

; Brandi, I. V.

; Cangussu, A. S. R.

Brazilian Journal of Biology

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

2023, Volume 83 elocation e269778

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

Abstract Bacteria responsible for causing infections are common in hospital environments, water, soil, and food products. The infection risk is intensified by the absence of public sanitation, poor quality of life, and food scarcity. These external factors promote the dissemination of pathogens by direct contamination or biofilm formation. In this work, we identified bacterial isolates obtained from intensive care units in the southern region of Tocantins, Brazil. We compared matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) techniques and 16S ribosomal ribonucleic acid (rRNA) molecular analysis; we also performed phenotypic characterization. Fifty-six isolates characterized using morphotinctorial tests were classified as gram-positive (80.4%; n = 45) and gram-negative (19.6%; n = 11) and were resistant to several antibiotic classes; notably, we identified the blaOXA-23 resistance gene in the ILH10 isolate. Microbial identification using MALDI-TOF MS resulted in the identification of Sphingomonas paucimobilis and Bacillus circulans. 16S rRNA sequencing revealed four isolates belonging to the genera Bacillus and Acinetobacter. The similarity was superior to 99% for Acinetobacter schindleri in the Basic Local Alignment Search Tool (BLAST), grouped in the clade superior to 90%. Several strains isolated from intensive care units (ICU) were resistant to various antibiotic classes. These techniques allowed for the identification of several microorganisms of importance in public health, enabling improvements in human infection control and proving the quality of inputs, food, and water.

Resumo As bactérias responsáveis por causar infecções são comuns em ambientes hospitalares, água, solo e produtos alimentícios. O risco de infecção é intensificado pela ausência de saneamento público, má qualidade de vida e escassez de alimentos. Esses fatores externos promovem a disseminação de patógenos por contaminação direta ou formação de biofilme. Neste trabalho, identificamos isolados bacterianos obtidos de unidades de terapia intensiva na região sul do Tocantins, Brasil. Comparamos técnicas de espectrometria de massa de tempo de voo com ionização por dessorção a laser assistida por matriz (MALDI-TOF MS) e análise molecular de ácido ribonucleico ribossômico 16S (rRNA); também realizamos caracterização fenotípica. Cinquenta e seis isolados caracterizados por testes morfotintoriais foram classificados como gram-positivos (80,3%; n = 45) e gram-negativos (19,6%; n = 11) e foram resistentes a várias classes de antibióticos; notavelmente, identificamos o gene de resistência blaOXA-23 no isolado de ILH10. A identificação microbiana usando MALDI-TOF MS resultou na identificação de Sphingomonas paucimobilis e Bacillus circulans. O sequenciamento do 16S rRNA revelou quatro isolados pertencentes aos gêneros Bacillus e Acinetobacter. A similaridade foi superior a 99% para Acinetobacter schindleri no BLAST, agrupado no clado superior a 90%. Várias cepas isoladas de ICU foram resistentes a várias classes de antibióticos. Essas técnicas permitiram a identificação de diversos microrganismos de importância em saúde pública, possibilitando melhorias no controle de infecções humanas e comprovando a qualidade dos insumos, alimentos e água.

https://doi.org/10.1590/1519-6984.269778

Does silicon attenuate PEG 6000-induced water deficit in germination and growth initial the seedlings corn
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Sousa, L. I. S.

; Brito, A. E. A.

; Souza, L. C.

; Teixeira, K. B. S.

; Nascimento, V. R.

; Albuquerque, G. D. P.

; Oliveira Neto, C. F.

; Okumura, R. S.

; Nogueira, G. A. S.

; Freitas, J. M. N.

; Monteiro, G. G. T. N.

Brazilian Journal of Biology

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

2023, Volume 83 elocation e265991

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

Abstract Water stress limits the initial growth and development of maize mass and grain, as well as the physiological process for absorbing the amount of mineral elements. The objective was to evaluate the effect of silicon on germination and growth of corn seedlings submitted to water deficit. The experiment was carried out in the laboratory and the experimental design was completely randomized (factorial 3 × 4), with three concentrations of calcium silicate (0.0; 1.0 and 2.0 mM) and 4 solutions of PEG-6000 to simulate different osmotic potentials (0, 0; -0.3; -0.6; -0.9 MPa). Germination percentage, germination speed index (GSI), mean germination time (MGT), percentage of non-germinated and abnormal germinated, length and dry matter of shoot, root and total seedlings were evaluated. Water deficiency reduced the parameters TG, GSI and MGT. The water deficit reduce the MSPA, MSR and MST with more than 80% reduction in mass from seedlings without deficiency to seedlings with deficiency. For CPA, CR and CT there was a reduction of at least 87%, 70% and 77%, respectively, among seeds without deficiency compared to seeds submitted to deficiency. The use of silicon in corn seeds did not attenuate the stress caused by water deficit simulated by PEG-6000.

Resumo O estresse hídrico limita o crescimento inicial e o desenvolvimento da massa e do grão de milho, assim como no processo fisiológico para a absorção da quantidade de elementos minerais. Objetivou-se avaliar o efeito do silício na germinação e no crescimento de plântulas de milho submetidas a deficiência hídrica. O experimento foi desenvolvido em laboratório e o delineamento experimental foi inteiramente casualizado (DIC) (fatorial 3 × 4), sendo três concentrações de Silicato de cálcio (0,0; 1,0 e 2,0 mM) e 4 soluções de PEG-6000 a simular diferentes potenciais osmóticos (0,0; -0,3; -0,6; -0,9 MPa). Foram avaliados a porcentagem de germinação, o índice de velocidade de germinação (IVG), o tempo médio de germinação (TMG), a porcentagem de não germinadas e de germinadas anormais, o comprimento e matéria seca da parte aérea, raiz e total das plântulas. A deficiência hídrica diminuiu os parâmetros TG, IVG e TMG. O déficit hídrico reduz a MSPA, MSR e MST com mais de 80% de redução da massa das plântulas sem deficiência para as plântulas com deficiência. Para CPA, CR e CT houve redução de, no mínimo, 87%, 70% e 77%, respectivamente entre as sementes sem deficiência em comparação as sementes submetidas a deficiência. A utilização de silício em sementes de milho não atenuou o estresse causado pela deficiência hídrica simulada por PEG-6000.

https://doi.org/10.1590/1519-6984.265991

Impacts of an urban flood control infrastructure on the limnology and ichthyofauna of a basaltic Cuesta stream (southeast Brazil)
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Siva, L. A.

; Kimura, R. S. Y.

; Brambilla, E. M.

; Silva, S. O.

; Nogueira, M. G.

Brazilian Journal of Biology

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

2023, Volume 83 elocation e276585

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

Abstract Strategies for flood control associated to extreme precipitation events in urban areas are urgent, in order to prevent not only material damages but also to avoid human losses. The construction of flood contention reservoirs (“piscinões”) has become a common engineering intervention in urban and peri-urban areas. However, there is a lack of studies focused on the evaluation of environmental impacts of this type of construction. This study intended to verify the ecological effects of a retention reservoir built directly on the course of the Cascata stream, Botucatu (SP). Three sampling sites were selected, located upstream the reservoir, in the reservoir and downstream. Samplings were carried out in July (winter - dry) and November (late spring - rainy) 2020. In situ measurements were obtained through a multiparameter probe (temperature, pH, electrical conductivity, dissolved oxygen, total dissolved solids, and oxidation-reduction potential) and water samples were collected for laboratory determinations (nitrogen, total phosphorus, thermotolerant coliforms, and chlorophyll-a). For fish sampling, manual trawls, sieves and hand nets were used, with a sampling effort of 10 throws per artefact and site. Despite the small distance between the sampling points (~1,300 m) considerable changes in the limnological conditions and fish community structure were observed. The studied environment is originally a small river surrounded by riparian forest, but this characteristic was abruptly changed in the reservoir stretch, with the direct exposition of a much larger water surface to intense solar radiation and atmosphere exchanges. Consequently, as evidenced by the PCA analysis, there was a considerable (stream-reservoir increase) of temperature, dissolved oxygen and chlorophyll. However, this spatial trend was partially disturbed by an accidental sewage-pipe rupture (posteriorly fixed) adjacent to the first sampling point, due to a previous event of extreme precipitation, which resulted in increased values of nutrients, chlorophyll, conductivity and thermotolerant coliforms. Eleven fish species were collected (two non-native), belonging to seven families and five orders. The upstream reference point (despite not be pristine), was characterized by the predominance of native species, while the reservoir condition favored the development of large populations of the non-native species. Despite the urgency of effective actions to prevent floods in urban areas, construction of contention reservoirs directly on stream courses should be avoided, due to their negative ecological impacts.

Resumo Estratégias de controle de cheias associadas a eventos extremos de precipitação em áreas urbanas são urgentes, a fim de prevenir não apenas danos materiais, mas também perdas humanas. A construção de reservatórios de contenção de cheias (“piscinões”) tornou-se uma intervenção comum da engenharia em áreas urbanas e periurbanas. No entanto, existe uma carência de estudos voltados para a avaliação dos impactos ambientais desse tipo de infraestrutura. Este estudo teve como objetivo verificar os efeitos ecológicos de um reservatório de contenção construído diretamente no leito do córrego Cascata, Botucatu (SP). Foram selecionados três pontos amostrais, localizados a montante do reservatório, no reservatório e a jusante. As amostragens foram realizadas em julho (inverno - seco) e novembro (final da primavera - chuvoso) de 2020. Foram feitas medidas in situ com sonda multiparamêtros (temperatura, pH, condutividade elétrica, oxigênio dissolvido, sólidos totais dissolvidos e potencial oxido-redução) e amostras de água foram coletadas para determinações laboratoriais (nitrogênio, fósforo total, coliformes termotolerantes e clorofila-a). Para a amostragem de peixes, foram utilizadas rede de arrasto manual, peneira e puçá, com um esforço amostral de 10 lances por artefato e local. Apesar da pequena distância entre os pontos de amostragem (~1.300 m), foram observadas mudanças consideráveis nas condições limnológicas e na estrutura da comunidade de peixes. O ambiente de estudo é originalmente um pequeno rio acompanhado por vegetação ripária, mas esta condição foi abruptamente alterada no trecho do reservatório, com a exposição direta de uma superfície de água muito maior à intensa radiação solar e trocas com a atmosfera. Consequentemente, conforme evidenciado pela ACP, houve um considerável aumento (riacho-reservatório) da temperatura, oxigênio dissolvido e clorofila. Contudo, houve um distúrbio desta tendência de variação espacial devido à ruptura de uma tubulação de esgoto (posteriormente reparada), adjacente ao ponto 1, decorrente de um evento extremo de precipitação, que elevou as concentrações de nutrientes, clorofila, condutividade e coliformes termotolerantes. Onze espécies de peixes foram coletadas (duas não nativas), pertencentes a sete famílias e cinco ordens. O ponto de referência a montante (apesar de não ser pristino), caracterizou-se pela predominância de espécies nativas, enquanto que a condição de reservatório favoreceu o desenvolvimento de grandes populações das espécies não-nativas. Apesar da urgência de ações efetivas para prevenir enchentes em áreas urbanas, as construções feitas diretamente no curso dos córregos devem ser evitadas, devido aos seus impactos ecológicos negativos.

https://doi.org/10.1590/1519-6984.276585

Scientific diving in Brazil: history, present and perspectives
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Leite, Tatiana S.

; Pinheiro, Igor E.

; Berchez, Flávio

; Bertoncini, Áthila A.

; Cima, Oswaldo M. Del

; Demetrescu, Irene E.

; Francini-Filho, Ronaldo B.

; Kikuchi, Ruy K.P

; Machado, Arthur A.

; Maia-Nogueira, Rodrigo

; Martins, Flavio L.

; Mendes, Liana F.

; Rambelli, Gilson

; Sampaio, Claudio L.S.

; Segal, Barbara

; Aguiar, Aline A.

; Auler, Augusto S.

; Barroco-Neto, José

; Bonaldo, Roberta M.

; Buchmann, Francisco S.

; Calippo, Flavio

; Cesar, Augusto

; Gama, Matheus A.C.

; Ghilardi-Lopes, Natalia

; Leão, Zelinda M.A.N.

; Lessa, Guilherme C.

; Menegola, Carla

; Pinheiro, Hudson T.

; Rocha, Luiz A.

; Sabino, José

; Seoane, José C.S.

; Sestokas, Julia

; Tiago, Cláudio C.

; Wegner, Ewerton

; Lotufo, Tito

Ocean and Coastal Research

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

2023, Volume 71 elocation e23045

Resumo: En | Texto: En | PDF: En

Abstract Scientific diving (SD) is defined as any diving activity that applies scientific procedures to produce subsidies for studies and technical works in underwater environments. The first report of an underwater scientific study in Brazil dates to the 19th century, in the Abrolhos reefs. Currently, in Brazil, scientific diving has been performed in various areas, from shallow coastal regions to remote and sometimes hard-to-reach places, such as oceanic islands, flooded caves, and icy areas like Antarctica. However, the regulation of SD in Brazil still lacks more concrete actions towards an effective and efficient self-regulation that offers physical safety to practitioners and institutional safeguards for organizations that use it in their research projects. Thus, this article aims to contribute to a better understanding of this critical issue in Brazil and to serve as a reference and incentive for the training of professionals and the development of these activities in the country. It includes: 1) a historical review of SD; 2) a diagnosis of the training and application of SD in Brazil; 3) the evolution of marine sciences in Brazil from the perspective of SD; 4) a review of the use of environmental assessment and underwater conservation techniques in oceans and internal waters; 5) an analysis of the evolution of scientific diver training in Brazil, including a diagnosis on training; 6) the history and updates of the rules, regulations, and safety of SD. Given all the potential of diving combined with specific techniques for research, monitoring, and marine and limnic science in Brazil, we aim to understand the evolution of scientific diving teaching and to outline perspectives in the country, as it is crucial for the training of qualified scientists capable of performing these underwater tasks. Finally, we present future plans for the development of this activity in Brazil from the point of view of research and the labor market.

https://doi.org/10.1590/2675-2824071.23036tsl

Biomarkers in Source Rocks from Barreirinha Formation (Devonian): Distribution and Paleoenvironment Significance
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Silva, Andrenilton F.

; Barros, Artur L. C.

; Sousa, Alek A. C.

; Jarvie, Daniel M.

; Calderón, Sebastian M.

; Brito, Ailton S.

; Nogueira, Afonso C. R.

; Souza, Alexandre A. de

; Lima, Sidney G. de

Journal of the Brazilian Chemical Society

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

Abr 2022, Volume 33 Nº 4 Páginas 369 - 383

Resumo: En | Texto: En | PDF: En

The Barreirinha Formation-Upper Devonian, is the main petroleum source rock of the Amazon Basin, deposited during the great Devonian Transgression, contributing to significant accumulations of organic matter (OM) in anoxic conditions, which allowed its preservation. The present work had the objective of characterizing the molecular composition of biomarkers in outcrops samples of the Barreirinha Formation, aiming to evaluate the paleoenvironment, thermal evolution, and the preservation of OM total organic carbon (TOC) and Rock-Eval pyrolysis indicate considerable amounts of immature OM deposited in a low oxygenation environment. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) data corroborate that the OM was deposited in a suboxic to the oxic environment and low salinity (absence or low relative abundance of β-carotane and gammacerane). 24-N-Propyl-cholestane was detected and identified by synthetic pattern co-injection. High concentrations of tetracyclic polyprenoids (TPPs) in ascending order from base to top, high hopane/sterane ratios, to suggest that the samples had a high molecular weight n-alkanes, C29 steranes, low thermal evolution, and anoxic depositional paleoenvironment.

https://doi.org/10.21577/0103-5053.20210156

Guidelines for the diagnosis and differential diagnosis of snakebite envenoming of ruminants in Brazil
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Graça, Flávio A.S.

; Caldas, Saulo A.

; França, Ticiana N.

; Brust, Luis A.

; Nogueira, Vivian A.

; Cecco, Bianca S.

; Santos, Bartolomeu B.N.

; Peixoto, Paulo V.

Pesquisa Veterinária Brasileira

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

2022, Volume 42 elocation e07105

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

RESUMO: No Brasil, acidentes ofídicos são frequentemente citados como causa de mortalidade em ruminantes, mas existem discrepâncias em relação a sua atual prevalência, seja por falta de diagnóstico ou por erros no diagnóstico diferencial. Entre os fatores que dificultam o diagnóstico estão as inconsistências para distinguir entre os acidentes causados por Bothrops e Crotalus, responsáveis por mais de 90% dos casos. Para o diagnóstico de envenenamentos por Lachesis muta, devem ser considerados os efeitos neurotrópico e proteolítico/hemolíticos concomitantes, a exemplo do que ocorre com algumas cascavéis norte-americanas (Crotalus scutulatus, entre elas). Este artigo descreve os principais achados clinicopatológicos e laboratoriais observados em casos de envenenamento pelas serpentes citadas e sugere um roteiro simplificado para o estabelecimento do diagnóstico e diagnóstico diferencial, a partir de uma sequência lógica, baseada em evidências epidemiológicas e achados clínicos, laboratoriais e patológicos.

ABSTRACT: In Brazil, snakebites are often cited as a cause of mortality in ruminants, but there are discrepancies in the literature regarding its actual prevalence, either by lack of diagnosis or by mistakes in the differential diagnosis. Among the factors that hinder the diagnosis are included the inconsistencies to distinguish between accidents caused by Bothrops and Crotalus, responsible for over 90% of the cases. For the diagnosis of accidents involving Lachesis muta, both the neurotropic and the proteolytic/hemolytic effects must be considered, similar to what is described in Crotalus scutulatus. This article describes the main clinical, pathological, and laboratory findings observed in envenoming by the aforementioned snakes and suggests procedures for establishing the diagnosis and differential diagnosis starting from a logical sequence, based on epidemiological evidence, clinical, laboratory, and pathological findings.

https://doi.org/10.1590/1678-5150-pvb-7105

Mitigation of the effects of salt stress in cowpea bean through the exogenous aplication of brassinosteroid
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Sousa, D. J. P.

; Nogueira, G. A. S.

; Teixeira, K. B. S.

; Monteiro, G. G. T. N.

; Brito, A. E. A.

; Nascimento, V. R.

; Albuquerque, G. D. P.

; Oliveira, T. J. M.

; Souza, L. C.

; Freitas, J. M. N.

; Oliveira Neto, C. F.

; Okumura, R. S.

Brazilian Journal of Biology

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

2022, Volume 82 elocation e260818

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

Resumo O feijão-caupi (Vigna unguiculata (L.) Walp.) é uma leguminosa amplamente cultivada por pequenos, médios e grandes produtores em diversas regiões brasileiras. No entanto, uma das preocupações para a produção de feijão-caupi no Brasil nos últimos anos é a baixa atividade pluviométrica nessas regiões, o que gera o acúmulo de sais na superfície. O objetivo deste trabalho foi avaliar os efeitos do estresse salino nos parâmetros de crescimento e atividade enzimática em plantas de feijão-caupi em diferentes concentrações de brassinosteróides. O experimento foi desenvolvido em casa de vegetação com delineamento experimental inteiramente casualizado em esquema fatorial 3 x 3. Os tratamentos consistiram de três níveis de brassinosteróides (0, 3 e 6 µM EBL) e três níveis de estresse salino (0, 50 e 100 mM NaCl). Os fatores de crescimento (altura, diâmetro e número de folhas) diminuíram na condição salina. Com a presença do brassinosteroide a altura não aumentou, mas o número de folhas sim, principalmente na dosagem salina de 100 mM NaCl. Na variável integridade de membrana, o brassinosteróide foi eficiente em ambas as dosagens de salinidade, o mesmo não ocorrendo com o teor relativo de água, onde a condição salina não afetou a quantidade de água na hortaliça, com a aplicação de brassino manteve-se elevada, diminuindo apenas na dosagem de NaCl 100 mM. A enzima nitrato redutase foi bastante afetada no sistema radicular mesmo com a aplicação de doses crescentes de brassino. Portanto, o uso de brassinosteroides como promotor de tolerância salina em plântulas de feijão-caupi foi positivo. A concentração de 3µM de EBL proporcionou o efeito mais satisfatório em tolerar os efeitos deletérios da condição salina. O mesmo não pode ser concluído para a concentração de 6µM de EBL que não promoveu tolerância a algumas variáveis.

Abstract Cowpea (Vigna unguiculata (L.) Walp.) is a legume widely cultivated by small, medium and large producers in several Brazilian regions. However, one of the concerns for the production of cowpea in Brazil in recent years is the low rainfall activity in these regions, which generates the accumulation of salts on the surface. The objective of this work was to evaluate the effects of salt stress on growth parameters and enzyme activity in cowpea plants at different concentrations of brassinosteroids. Experiment was developed in a greenhouse using a completely randomized experimental design in a 3 x 3 factorial scheme. The treatments consisted of three levels of brassinosteroids (0, 3 and 6 µM EBL) and three levels of salt stress (0, 50 and 100 mM NaCl). Growth factors (height, diameter and number of leaves) decreased in the saline condition. With the presence of brassinosteroid the height did not increase, but the number of leaves did, mainly in the saline dosage of 100 mM NaCl. In the variable membrane integrity, brassinosteroid was efficient in both salinity dosages, the same not happening with the relative water content, where the saline condition did not affect the amount of water in the vegetable, with the application of brassino it remained high, decreasing only at dosage 100 mM NaCl. The nitrate reductase enzyme was greatly affected in the root system even with the application of increasing doses of brassino. Therefore, brassinosteroids as a promoter of saline tolerance in cowpea seedlings was positive. The concentration of 3µM of EBL provided the most satisfactory effect in tolerating the deleterious effects of the saline condition. The same cannot be concluded for the concentration of 6µM of EBL that did not promote tolerance to some variables.

https://doi.org/10.1590/1519-6984.260818

Hydric and saline stress on Phaseolus lunatus L. seeds
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Sá, F. V. S.

; Oliveira, F. S.

; Torres, S. B.

; Paiva, E. P.

; Nogueira, N. W.

; Sarmento, E. C. S.

; Melo, A. S.

Brazilian Journal of Biology

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

2022, Volume 82 elocation e233550

Resumo: En | Texto: En | PDF: En

https://doi.org/10.1590/1519-6984.233550 151 downloads

10.

Agronomic traits and chemical composition of forage sorghum plants fertilized with poultry litter and fermentative profile of silages
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics

Lucena, Nagnaldo T.

; Santos, Edson M.

; Oliveira, Juliana S.

; Perazzo, Alexandre F.

; Cruz, Gabriel F.L.

; Pereira, Danillo M.

; Pereira, Gildênia A.

; Macêdo, Alberto J.S.

; Ramos, Rosângela C.S.

; Nogueira, Messias S.

Chilean journal of agricultural research

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

Dez 2021, Volume 81 Nº 4 Páginas 575 - 584

Resumo: En | Texto: En | PDF: En

ABSTRACT It is essential to determine the productive potential and quality of forage sorghum (Sorghum bicolor (L.) Moench) silages using alternative and organic inputs, such as poultry litter (PL), intending to higher efficiency, and sustainable development of animal production systems in the world. Poultry litter fertilization has been widely used in crops for silage production, where it is believed that fertilization with PL can influence the fermentation profile and composition of forage sorghum silages. The objective of this study was to evaluate different levels of fertilization with PL on the agronomic and quality characteristics of forage sorghum silage ‘BRS Ponta Negra’. For determination of agronomic and productive characteristics, randomized blocks design was adopted, the treatments were different PL levels: 5, 10, and 15 Mg ha-1. While for the evaluation of silage characteristics, the design was completely randomized. With fertilizer doses, a linear increase was observed for plant height, stem diameter, leaf length, and consequently for fresh and DM productions. Linear reduction was observed for neutral detergent fiber, while crude protein and pH contents of silages increased linearly with PL levels. Quadratic effect occurred for gas and effluent losses. Poultry litter may be an alternative source to supply the N needs in the production of sorghum for silage under experimental similar conditions. Associating productivity with cultivation efficiency, the PL level 13.46 Mg ha-1 is recommended for presenting the highest N agronomic efficiency and good nutritional quality of the silage.

101 downloads

11.

REDUçãO DE CO2 EM HIDROCARBONETOS E OXIGENADOS: FUNDAMENTOS, ESTRATéGIAS E DESAFIOS
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Silva, Gelson T. S. T. da

; Lopes, Osmando F.

; Dias, Eduardo H.

; Torres, Juliana A.

; Nogueira, André E.

; Faustino, Leandro A.

; Prado, Fernando S.

; Patrocínio, Antônio O. T.

; Ribeiro, Caue

Química Nova

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

Ago 2021, Volume 44 Nº 8 Páginas 963 - 981

Resumo: Pt | Texto: Pt | PDF: Pt

CO2 REDUCTION TO HYDROCARBONS AND OXYGENATES: FUNDAMENTALS, STRATEGIES AND CHALLENGES. The development of renewable energy sources (e.g., solar and wind) moves foward, the tendance for replacing fossil fuels increases. However, these technologies have as primary barriers to industrial processes’ efficiency and especially storage. Thus, CO2 reduction routes using these energy sources could chemically store part of the energy as fuels or chemicals, offering alternatives to current oil and gas industry. This process is inspired by photosynthesis, e.g., photochemical or electrochemical processes, using homogeneous or heterogeneous catalysts. Nevertheless, this reaction is thermodynamically unfavorable and has very slow kinetics, given the high stability of the CO2 molecule and the complexity of the redox reactions involved. Therefore, this review addresses this process’s kinetic and thermodynamic challenges, and the fundamental concepts of the photo(electro)chemical processes for CO2 reduction, besides presenting and discussing the materials with the potential to act as catalysts. The main reaction mechanisms and advances in the understanding of such processes are discussed, as well as future perspectives

https://doi.org/10.21577/0100-4042.20170745 107 downloads

12.

Solventes eutéticos naturais profundos (NADES) no preparo de amostras de rocha fosfática e suplemento mineral para determinação elementar por técnicas de plasma
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Santana, Ana P. R.

; Andrade, Daniel F.

; Guimarães, Taciana G. S.

; Amaral, Clarice D. B.

; Oliveira, Andrea

; Nogueira, Ana R. A.

; Gonzalez, Mario H.

Química Nova

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

Jun 2021, Volume 44 Nº 6 Páginas 689 - 695

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

Natural deep eutectic solvents (NADES) based on xylitol, citric acid, and malic acid were synthesized and used in ultrasound-assisted extraction (UAE) and heating-bath extraction of phosphate rock and mineral supplement samples. Arsenic, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, P and Zn were determined by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP OES). The results showed the NADES as promising solvents for extraction of inorganic matrices compared to reference values and concentrations obtained using microwave-assisted acid digestion (MW-AD). Significant differences were observed for some elements, suggesting different chemical interactions between the synthesized NADES and each monitored element. For analytes extraction of phosphate rock, UAE presented the best results for As, Cr and P. Zinc was extracted with UAE and heating bath. Concerning mineral supplement, no significant differences were observed for Ca (UAE), Cd (UAE and heating bath), K (UAE and heating bath), Mn (UAE and heating bath), Na (UAE and heating bath), and P (UAE and heating bath). The NADES is a greener and a potentially alternative for the sample preparation compared to the official methods of analysis, can being used as selective extractor solvent in conventional sample preparation methods.

https://doi.org/10.21577/0100-4042.20170723 130 downloads

13.

Influence of migration on the thought process of individuals at ultra-high risk for psychosis
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Nogueira, Arthur S.

; Andrade, Julio C.

; Serpa, Mauricio H.

; Alves, Tania M.

; Freitas, Elder L.

; Hortêncio, Lucas

; van de Bilt, Martinus T.

; Rössler, Wulf

; Gattaz, Wagner F.

; Loch, Alexandre A.

Brazilian Journal of Psychiatry

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

Jun 2021, Volume 43 Nº 3 Páginas 285 - 288

Resumo: En | Texto: En | PDF: En

Objective: To assess the influence of migration on the psychopathological presentation of individuals at ultra-high risk for psychosis (UHR) in São Paulo, Brazil. Methods: This study is part of the Subclinical Symptoms and Prodromal Psychosis (SSAPP) project, a cohort study in São Paulo, Brazil, designed to follow individuals at UHR. After screening with the Prodromal Questionnaire (PQ) and a clinical interview, the Global Assessment of Functioning (GAF) was administered, a neuropsychological assessment was performed, sociodemographic and migration data were obtained. We then analyzed UHR individuals who had migration data to see if migration had any effect on their cognition and psychopathology. Chi-square tests were used for categorical variables, and Student’s t test or analysis of variance (ANOVA) were used for nonparametric and parametric distributions, respectively. Results: The sample was composed of 42 at-risk subjects, of whom 5 had a migration history in the past two generations. Those with migration history showed significantly more formal thought disturbances (p = 0.012) and sleeping problems (p = 0.033) compared to those without. Conclusions: Our data reinforce migration as a risk factor for psychosis in developing countries as well, and highlights the importance of studying the specific effect of this factor in UHR psychopathology.

https://doi.org/10.1590/1516-4446-2019-0685 127 downloads

14.

Alternative Approaches Applied to Inductively Coupled Plasma Techniques: Multi-Flow and Two-Flow Calibration
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Machado, Raquel C.

; Silva, Ana Beatriz S.

; Andrade, Daniel F.

; Pinheiro, Fernanda C.

; Williams, Charles B.

; Donati, George L

; Nogueira, Ana Rita A.

; Pereira-Filho, Edenir R.

Journal of the Brazilian Chemical Society

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

Abr 2021, Volume 32 Nº 4 Páginas 842 - 851

Resumo: En | Texto: En | PDF: En

Multi-flow calibration (MFC) is based on monitoring the analytical signal from a single calibration standard solution at several different nebulization gas flow rates (Q), which normalizes plasma conditions and minimizes matrix effects. In the present study, MFC was evaluated, for the first time, applied to inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) to analyze different and complex-matrix samples. Al, As, Cd, Cr, Cu, Mn, Pb, and Zn were determined by ICP OES, while As, Cd, Co, Cu, Hg, Mo, Mn, Ni, Se, Sb, Pb, and V were determined by ICP-MS. MFC results were compared with those obtained using external standard calibration (EC) for both techniques and in all cases, MFC showed equal or superior accuracy (recoveries between 80-120%) compared to EC, and lower relative standard deviation (RSDs ≤ 10%). Several tests were also performed using only two nebulization gas flows to build linear models for calibration (called two-flow calibration, TFC) and the accurate results (recoveries ranged from 80 to 110% for ICP OES and from 81 to 102% for ICP-MS) suggests that this strategy can be also applied, resulting in a method with high sample throughput.

https://doi.org/10.21577/0103-5053.20200235 156 downloads

15.

Evaluation of the Seasonality and Extraction Method on the Polar Extracts of Croton grewioides Baill. by Chromatogram Fingerprinting and Isolation of a New Triglycosylated Flavonoid
Facebook Twitter

Outras redes sociais
Google+
LinkedIn
Reddit
StambleUpon
CiteULike
Mendeley
Outras redes

Métricas
- SciELO Analytics
- Dimensions
- PlumX
- Altmetric

Prado, Vilma M. J.

; Jesus, Raphael A. de

; Oliveira, Julio M. A.

; Pereira, Camila S. A.

; Blank, Arie F.

; Pereira-Filho, Edenir R.

; Cass, Quezia B.

; Lima, Juliana M. de

; Ferreira, Antonio G.

; Nogueira, Paulo C. L.

; Moraes, Valéria R. S.

Journal of the Brazilian Chemical Society

Métricas do periódico
- Sobre o periódico
- SciELO Analytics

Fev 2021, Volume 32 Nº 2 Páginas 385 - 394

Resumo: En | Texto: En | PDF: En

Croton grewioides Baill. popularly known as “canelinha” or “canelinha-de-cheiro” has been used for the treatment of influenza, antitussive, febrifuge and headache; however, the study of its phytochemical composition is limited. The aim of this study was to investigate the effect of the extraction method and seasonality through leaf extracts of four accessions of Croton grewioides by fingerprint chromatograms aided by principal component analysis to analyze the differences and similarities among the samples. We aimed also to provide chemical characterization of isolated secondary metabolites using semi-preparative liquid chromatography. The results showed that only the chemical profile of the methanolic extracts of accessions 101 and 113 were influenced by the seasonality. For the first time, four flavonoids were isolated through semi-preparative chromatography in this species, characterized as quercetin 3-O-β-D-galactopyranosyl-(1→2)-α-L-rhamnopyranoside-(1→6)-α-L-rhamnopyranoside (1), quercetin 3-O-β-D-galactopyranosyl-(1→2)-α-apiopyranoside-(1→6)-α-L-rhamnopyranoside (2), quercetin 3-O-glucopyranoside (3) and 3-O-methyl-quercetin (4), the flavonoid (2) has been recognized as a new triglycosylated derivative.

https://doi.org/10.21577/0103-5053.20200190 249 downloads

Exibindo

itens por página

Página de 10 Próxima

Selecione um ou mais resultados

Todos Ordem alfabética

Resultados

Gráfico comparativo Download CSV

Visualizar estatísticas de

Enviar resultado

E-mail do(s) destinatários*

Utilize ; (ponto e vírgula) para mais de um e-mail.

Enviar por e-mail

Esta página

Registros selecionados

Todos os registros (max. 300)

Alterar remetente, assunto e comentários

Seu email

Assunto

Comentários

Alterar remetente, assunto e comentários

Exportar resultados

Formato de exportação:

RIS (para EndNote, ProCite, Reference Manager, RefWorks, Citavi, etc.)

BibTeX

Citação

CSV (para Excel, etc)

Exportar:

Esta página

Itens selecionados

Todos os registros (max. 2000)

Mostrar mais

Sem resultados

Não foram encontrados documentos para sua pesquisa

Glossário e ajuda para busca

Você pode enriquecer sua busca de uma forma muito simples. Use os índices de pesquisa combinados com os conectores (AND ou OR) e especifique cada vez mais sua busca.

Por exemplo, se você deseja buscar artigos sobre
casos de dengue no Brasil em 2015, use:
ti:dengue and publication_year:2015 and aff_country:Brasil

Veja abaixo a lista completa de índices de pesquisa que podem ser usados:

Cód. do Índice	Elemento
ti	título do artigo
au	autor
kw	palavras-chave do artigo
subject	assunto (palavras do título, resumo e palavras-chave)
ab	resumo
ta	título abreviado da revista (ex. Cad. Saúde Pública)
journal_title	título completo da revista (ex. Cadernos de Saúde Pública)
la	código do idioma da publicação (ex. pt - Português, es - Espanhol)
type	tipo do documento
pid	identificador da publicação
publication_year	ano de publicação do artigo
sponsor	financiador
aff_country	código do país de afiliação do autor
aff_institution	instituição de afiliação do autor
volume	volume do artigo
issue	número do artigo
elocation	elocation
doi	número DOI
issn	ISSN da revista
in	código da coleção SciELO (ex. scl - Brasil, col - Colômbia)
use_license	código da licença de uso do artigo

SciELO - Scientific Electronic Library Online
Rua Dr. Diogo de Faria, 1087 – 9º andar – Vila Clementino 04037-003 São Paulo/SP - Brasil
Email: scielo@scielo.org

Todo o conteúdo de www.scielo.org, exceto onde está identificado, está licenciado sob uma Licença Creative Commons.
saiba mais »