Os microplásticos são considerados como um tipo de contaminante emergente que têm despertado grande preocupação dos estudiosos e sociedade em geral, sobretudo quando atingem organismos aquáticos e entram em cadeias alimentares. O objetivo deste trabalho foi estabelecer uma metodologia para identificação da presença de microplásticos em peixes da espécie Astyanax fasciatus. Para o estudo de caso, foi selecionada a represa Bortolan, localizada em Poços de Caldas (MG). A coleta dos indivíduos foi realizada em um ponto localizado na margem esquerda da represa. No ponto de coleta foram medidas as seguintes variáveis da qualidade da água: temperatura (oC), pH, condutividade elétrica (μS/cm), oxigênio dissolvido (mg/L), sólidos totais dissolvidos (mg/L) e turbidez (NTU). As coletas foram realizadas nos dias 02 e 06 de setembro de 2023. Os peixes coletados foram submetidos as seguintes etapas para a identificação dos microplásticos: a) registro das variáveis biométricas; b) retirada e digestão do trato gastrointestinal; c) filtração do material digerido e d) secagem e observação dos filtros em microscópio óptico. Para a digestão da matéria orgânica (trato intestinal) foi utilizada solução de hidróxido de potássio (KOH 10%) em aquecimento a 60 oC. Após a digestão, as amostras foram filtradas e os filtros observados em microscópio óptico. Os resultados das variáveis de qualidade da água atenderam a Resolução CONAMA 357/2005 para corpos hídricos enquadrados como Classe 2. As observações em microscopia óptica evidenciaram a presença de microplásticos nos exemplares de Astyanax fasciatus, sendo encontradas fibras plásticas com colorações variadas. A metodologia empregada demonstrou resultados adequados para a identificação dos microplásticos nas espécies coletadas, o que evidencia sua aplicação e novos estudos em outros ambientes aquáticos.
O presente estudo teve como objetivo analisar e comparar a composição físico-química e centesimal da banana verde e da banana madura e apresentar os principais benefícios nutricionais, terapêuticos e organolépticos dos frutos. Foram determinados a composição centesimal da banana verde e madura, bem como o teor de sólidos solúveis, potencial hidrogeniônico (pH) e acidez titulável. Os dados foram submetidos à análise de comparação de médias pelo t-Student ao nível de 95% de significância. Nos resultados a banana madura apresentou valores mais altos para acidez titulável, sólidos solúveis, carboidratos e proteínas, enquanto a banana verde obteve valores elevados para umidade e lipídio. Deste modo, conclui-se que as bananas no estado verde e maduro apresentaram características diferentes na composição físico-química e centesimal.
This article investigates the influence of adding polyurethane with refined coal to high-strength mortar, evaluating its mechanical and physics. The tests conducted for this study included X-ray diffraction, compressive strength, elastic modulus, and tensile strength. Results showed that the compressive strength of the mortar decreased when refined coal was incorporated into the reference mortar, and the inclusion of polyurethane in this mixture led to a further reduction in compressive strength. Additionally, a decrease in the elastic modulus was observed with the addition of refined coal, and the inclusion of polyurethane in this mixture caused an additional reduction. The porosity of the mortar significantly increased with the addition of polyurethane to the mortar containing refined coal. In summary, adding polyurethane and refined coal to high-strength mortar compromises its mechanical properties, particularly through a re-duction in compressive strength, elastic modulus, tensile strength, and an increase in porosity. Although polyurethane contributes to flexibility and adhesion between particles, its interaction with refined coal creates a more porous structure, potentially impairing the material’s durability and strength.
In this research work, the problems of connection between various harmful substances emitted into the atmosphere and population morbidity indicators were analyzed in Navoi and Zarafshan, two important cities of the Navoi region, located in the industrialized and arid climate region of the Republic of Uzbekistan, located in the Central Asian region. The obtained results show that in the city of Navoi, there is a high correlation between diseases related to the respiratory system, diseases of the blood and blood-forming organs and immune system, diseases of the nervous system, and annual harmful substances released into the atmosphere. In the city of Zarafshan, there is a strong direct connection between the harmful substances released into the atmosphere and diseases related to the digestive organs, that is, the increase or decrease of various harmful substances in a certain amount, as mentioned above It can also increase or decrease the mentioned diseases. In conclusion, there is a direct correlation between the environmental conditions of industrialized and arid climate regions and the issues of public health, and the increase or decrease of one affects the trend of the other directly. It is more important than ever to develop the necessary measures with a proper understanding of this causal effect. Taking into account all the above points, we have developed some suggestions and recommendations.
Heavy metals are metals with high atomic weight and substances with high electrical conductivity that voluntarily lose their electrons to form cations. The heavy metal biomonitoring and entomofauna distribution of enyigba mines in southeast, Nigeria was studied to determine the contamination of heavy metals base and attendant health risks using standard entomological techniques and atomic absorption spectrophotometer (AAS). Insects examined were Reticulitermes flavipes, Zonocerus elegans, Acraea acrita, and Crematogaster sp collected from Royal Salt mining sites. The study revealed the accumulation index of Po4 (683.70±677.50) was high followed by Mn, (11.00 ±10.90) Cu, (7.600 ±6.60) Cd, (0.350±0.145) at p<0.05. This is high compared to the codex standards. ANOVA results declared the concentration of heavy metals above permissible limits with a significant difference between site A (SA) and the control site (CS) at (p<0.0001). Also, there is an important difference observed between site A (SA) and site B (SB) (p<0.0001). The relatively higher concentrations of metals were found in Orthoptera, followed by termite where ants recorded the lowest metal concentration. The study further revealed that remarkable values were recorded in the Control Site (CS) (32944) followed by (SB) (20904) while SA recorded the least value (6644). However, the low species diversity and abundance in different sites is an indication of the impacts of heavy metals accumulation in the sites. However, accumulation of PO4 in the insects, especially at sites A and B, showed the effects of mining on PO4 generation is high and could pose health risks to human life if not mitigated. However, the wet season recorded higher abundance compared to the dry season on Reticulitermes flavipes followed by Crematogaster sp. whereas Acraea acrita recorded the least abundance.
