Search

Your search keyword '"Marcelo Gomes Almeida"' showing total 5 results
Start Over Author "Marcelo Gomes Almeida"
5 results on '"Marcelo Gomes Almeida"'

1. Mercury biomagnification in an ichthyic food chain of an amazon floodplain lake (Puruzinho Lake): Influence of seasonality and food chain modeling

Author

Lucas Silva Azevedo, Inácio Abreu Pestana, Marcelo Gomes Almeida, Adriely Ferreira da Costa Nery, Wanderley Rodrigues Bastos, and Cristina Maria Magalhães Souza

Subjects
Mercury, Food chain modeling, Amazon, Biomagnification, Seasons, Floodplain, Environmental pollution, TD172-193.5, Environmental sciences, GE1-350
Abstract

Mercury (Hg) biomagnification in fish food chains is a relevant subject due to the high fish consumption of the Amazonian population and the high toxicity of this metal. In the Amazon, floodplain lake hydrodynamics change considerably along the four seasons of the hydrological cycle (rising water, high water, falling water and low water), which can influence Hg bioaccumulation in fish. The main aim of this study was to evaluate if Hg biomagnification is influenced by seasonality in a floodplain lake (Puruzinho Lake) in the Brazilian Amazon. Additionally, the influence of food chain modeling on measurement of Hg biomagnification was tested. Hg concentrations and stable isotope signatures (carbon and nitrogen) were estimated in four species, Mylossoma duriventre (herbivorous), Prochilodus nigricans (detritivorous), Cichla pleiozona (piscivorous) and Serrasalmus rhombeus (piscivorous). The “trophic magnification slope” (TMS) of the food chain composed by the four species was calculated and compared among the four seasons. There was no significant seasonal variation in TMS among rising water, high water, falling water and low water seasons (p = 0.08), suggesting that Hg biomagnification does not change seasonally. However, there was significant variation in TMS among different food chain models. Lower TMS was observed in a food chain composed of detritivorous and piscivorous fish (0.20) in comparison with a food chain composed of the four species (0.26). The results indicate food chain modeling influences TMS results.

Published
2021
Full Text
View/download PDF

2. CONTROLE DO BIOFILME SUPRAGENGIVAL E O USO DO FLUORETO ESTANHOSO COMO ADJUVANTE NO TRATAMENTO DA GENGIVITE: REVISÃO DE LITERATURA

Author

Marcelo Gomes Almeida, Luciana Dondonis Daudt, and R Braum

Subjects
Plaque index, business.industry, Gingival bleeding index, Clinical performance, Dentistry, chemistry.chemical_compound, Gingivitis, chemistry, Chemical agents, Dentifrice, General Earth and Planetary Sciences, Medicine, medicine.symptom, business, Fluoride, General Environmental Science
Abstract

Agentes químicos com capacidade de ação no biofilme dental e com propriedades anti-inflamatórias têm sido amplamente inseridos em produtos para uso caseiro na Odontologia. Esses podem representar um recurso adjuvante no tratamento da gengivite, de maneira a otimizar resultados clínicos de pacientes em tratamento. Diante da diversidade dos produtos disponíveis no mercado, faz-se necessário que o cirurgião-dentista conheça o desempenho clínico desses agentes a fim de prescrever, com propriedade, os mais adequados para cada paciente. O objetivo deste trabalho foi abordar o uso de dentifrícios contendo fluoreto estanhoso como alternativa terapêutica no tratamento da gengivite através de uma revisão de literatura. Para esse fim, foi realizada pesquisa nas bases de dados PubMed, Scielo e Google Acadêmico em busca de artigos que utilizaram os seguintes descritores: "stannous fluoride", "gingivitis control" e “antimicrobial dentifrices”, sem filtros para restringir período de tempo. De acordo com os artigos incluídos nesta revisão, pode-se afirmar que o uso de dentifrícios com fluoreto estanhoso possibilita uma redução significativa tanto nos índices de placa visível, quanto nos índices de sangramento gengival. Através da revisão de literatura realizada, pode-se afirmar que a indicação de dentifrícios contendo fluoreto estanhoso é segura e representa um bom recurso como controle coadjuvante do biofilme supragengival e no tratamento da gengivite.

Published
2020
Full Text
View/download PDF

3. Spatial-temporal dynamics of Cr in fish from Puruzinho Lake (Western Amazon) and dietary risk assessment

Author

Luiza Silva do Nascimento, Layra de Oliveira Silva, Sophia Menezes de Azevedo, Ronaldo de Almeida, Marcelo Gomes Almeida, Lucas Silva Azevedo, Wanderley Rodrigues Bastos, Cristina Maria Magalhães de Souza, and Inácio Abreu Pestana

Subjects
Environmental Engineering, Health, Toxicology and Mutagenesis, Public Health, Environmental and Occupational Health, Fishes, General Medicine, General Chemistry, Mercury, Pollution, Risk Assessment, Lakes, Environmental Chemistry, Animals, Cattle, Water Pollutants, Chemical, Environmental Monitoring
Abstract

Cr contamination is a growing concern in the Amazon. Along with the rise of cattle farming in the region, tanneries are becoming more common and threatening environmental quality, since the effluents from this activity are rich in Cr. The objective of this study was to evaluate the seasonal and spatial dynamics of Cr in fish with different feeding habits from Puruzinho Lake, located in the Madeira River basin, also determining the daily intake of Cr associated with the consumption of these fish by the population that lives around the lake. Seasonality and feeding habits directly affected Cr dynamics in fish (p 0.0001), with medians of Cr concentration ranging between 0.07 mg kg

Published
2022

Catalog

Books, media, physical & digital resources
See catalog results