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Made available in DSpace on 2021-06-25T10:31:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-21 Despite the wide range of possible applications of nanopesticides, the mechanisms involved in their enhanced action remain largely unknown. Understanding the interaction between nanopesticides and plants is crucial for evaluating their potential safety application. Using an experimental and theoretical approach, this study aimed to investigate the target effect of paraquat-loaded chitosan/tripolyphosphate nanoparticles (ca. 200 nm) on photosystem I (PSI). Electrochemical analysis showed distinct electroactivity behaviour between the encapsulated and non-encapsulated herbicide. The amount of lipid peroxidation, photooxidizable P700 reaction centre content, and NADPH/NADP+ ratio levels were significantly decreased in spinach leaf tissue exposed to the nanoherbicide compared to those with the non-encapsulated herbicide. The data also revealed that the nanoformulation might promote oxidative stress based on changes observed in antioxidant enzymes. Also, molecular docking results showed a preferential disposition of the herbicide paraquat and paraquat-tripolyphosphate complex (TPP:PQ) in the ligand domain close to FAD and Glu312. Due to the inhibitor's strategic position in the catalytic pocket, a model of electron-capture is proposed, where the herbicide disturbs the redox process NADP+ ⇌ NADPH by capturing electrons to reduce itself. Finally, our findings provide important insights where the redox behaviour of paraquat may play a key role in the enhanced efficiency of nanoherbicides to the target binding site. Plant Resources Study Group Natural Resources Program Center for Natural Resources Study (CERNA) Mato Grosso Do sul State University (UEMS) São Paulo State University (UNESP) Department of Physics and Chemistry Faculty of Engineering Department of Pharmacology Institute of Biomedical Sciences University of São Paulo (USP) Optics and Photonics Group Institute of Physics Federal University of Mato Grosso Do sul (UFMS) School of Life Science University of Essex Colchester São Paulo State University (UNESP) Department of Physics and Chemistry Faculty of Engineering

A morfometria de sementes possui importância taxonomica, filogenetica e ecologica, sobretudo quando se trata de arvores nativas do Cerrado. Neste estudo, foram discutidas as potencias relacoes entre os caracteres dimensionais das sementes e o ambiente de ocorrencia em populacoes de plantas de Dimorphandra mollis Benth., de um cerrado sensu stricto (Css) e uma floresta estacional semidecidual (FES). Foram determinadas medidas de comprimento, diâmetro e espessura das sementes, calculou-se tambem os diâmetros medios; geometrico (DMG), equivalente (DME), aritmetico (DMA), area superficial (A s ), relacao de aspecto (R a ), e esfericidade (O). As sementes do Css apresentaram menor comprimento (media 10,68 mm) e menor diâmetro (media 5,35 mm), enquanto que, as sementes da FES exibiram maior comprimento (media 12,68 mm) e maior diâmetro (media 7,86 mm), com diferenca significativa de 5% (p

Sewage sludge (SS), a solid residue of effluent treatment, is rich in organic matter and nutrients, while also containing heavy metals and other potential contaminants. The feasibility of employing SS as a substrate component for seedling production depends on its composition and dose, as well as on the tolerance limit of individual plant species. To expand the knowledge base on the use of SS in the production of plants native to the Brazilian Cerrado biome, we evaluated the physiological responses and quality of Alibertia edulis seedlings grown under distinct SS concentrations. Chlorophyll a fluorescence (ChlF), stomatal conductance (gs), leaf temperature (Lt), biomass, growth, and seedling quality were investigated. At 25%, SS improved growth, biomass, and seedling quality, while substrates containing 50% or more SS affected gs, Lt, and ChlF. Seedling quality was strongly worsened by SS at 75% and 100%, as shown by lower biomass and impaired growth, including leaf symmetry loss and leaf deformities possibly related to contaminants, particularly heavy metals. Accordingly, we conclude that SS exhibited potential as a fertilizer at concentrations below 50%, but exerted a toxic effect on seedlings at higher concentrations.

Made available in DSpace on 2022-04-29T08:33:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-20 A new highly sensitive, selective, and inexpensive electrochemical method has been developed for simultaneously detecting diethylstilbestrol (DES) and 17β-estradiol (E2) in environmental samples (groundwater and lake water) using a graphite sensor modified by cerium oxide nanoparticles (CPE-CeO2 NPs). The developed sensor and the materials used in its preparation were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The ab initio simulation was used to evaluate the adsorption energies between both DES and E2 with the surface of the sensor. The peak current of oxidation of both hormones showed two regions of linearity. The region of greatest sensitivity was observed for the linear range of 10 nM–100 nM. The detection and quantification limits for this concentration range were 0.8/2.6 nM and 1.3/4.3 nM for DES and E2, respectively. The analytical performance of the developed method showed high sensitivity, precision, repeatability, reproducibility, and selectivity. The CPE-CeO2 NPs sensor was successfully applied to simultaneously detect DES and E2 in real samples with recovery levels above 98%. Programa de Pós-Graduação em Recursos Naturais Universidade Estadual de Mato Grosso do Sul (UEMS), P.O. Box 351 Instituto de Ciências Biomédicas Universidade de São Paulo (USP), Av. Prof. Lineu Prestes, 1374, Butantã Instituto de Química Universidade Estadual de Campinas (UNICAMP), Rua Josué de Castro, s/n, Cidade Universitária Departamento de Física e Química Faculdade de Engenharia de Ilha Solteira Universidade Estadual Paulista (UNESP), Avenida Brasil, 56, Centro Departamento de Física e Química Faculdade de Engenharia de Ilha Solteira Universidade Estadual Paulista (UNESP), Avenida Brasil, 56, Centro

Excessive and indiscriminate use of the herbicide glyphosate (GLY) leaves the environment susceptible to its contamination. This work describes the development of a simple, inexpensive, and efficient electroanalytical method using graphite oxide paste electrode (GrO-PE) for the direct determination of GLY traces in groundwater samples, soybean extracts, and lettuce extracts. Under optimal experimental conditions, the developed sensor exhibited a linear response of the peak current intensity vs. the concentration, in the range of 1.8 × 10−5 to 1.2 × 10−3 mol L−1 for GLY. The limits of detection and quantification are 1.7 × 10−8 mol L−1 and 5.6 × 10−8 mol L−1, respectively. The methodology developed here demonstrated a strong analytical performance, with high reproducibility, repeatability, and precision. Moreover, it successfully avoided interference from other substances, showing high selectivity. The GrO-PE sensor was effectively applied to determine GLY traces in real samples with recovery rates ranging from 98% to 102%. Results showed that the GrO-PE is effective and useful for GLY detection, with the advantage of not involving laborious modifications and complicated handling, making it a promising tool for environmental analysis.

Made available in DSpace on 2020-12-12T02:13:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-11-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Glyphosate (Gly) is the most widely used herbicide in the world and has broad-spectrum and non-selective activity. Its indiscriminate use hence risks contamination of water bodies and can affect living organisms, especially sensitive or resistant non-target plants. Despite this, studies on physiological mechanisms and Gly remediation in Neotropical aquatic plants remain limited. This study aims to evaluate the physiological mechanisms of the aquatic macrophyte Salvinia biloba on exposure to different concentrations of a Gly commercial formulation (Gly-CF) and a Gly analytical standard (Gly-AS). Furthermore, using square-wave voltammetry (SWV), we determined whether the studied plant could remove Gly from water. Our data suggest that Gly-AS and Gly-CF induce similar physiological responses in S. biloba. However, Gly-CF was more phytotoxic. Depending on the concentration, the two forms of Gly affected the plants, decreasing the chlorophyll a and b contents and the photosystem II (PSII) photochemical activity. The data also revealed that Gly promoted oxidative stress and increased the shikimic acid concentration. At the same time, the plants removed Gly from water, with 100% removal for 1 mg L−1 Gly and above 60% removal for the other concentrations studied. Therefore, our results suggest that S. biloba may be a potential phytoremediation agent for low Gly concentrations, since 1 mg L−1 Gly was completely removed and exhibited low phytotoxicity. This study deepens our scientific understanding of the Gly impact on and the phytoremediation potential of S. biloba. Grupo de Estudos em Recursos Vegetais Programa de Pós-Graduação em Recursos Naturais Universidade Estadual de Mato Grosso do Sul CP 350 79804-970 Grupo de Estudos em Eletroquímica Programa de Pós-Graduação em Recursos Naturais Universidade Estadual de Mato Grosso do Sul CP 350 79804-970 Laboratório de Nanoquímica Ambiental Departamento de Física e Química Faculdade de Engenharia de Ilha Solteira Universidade Estadual Paulista (UNESP) Centro, Avenida Brasil, 56 Laboratório de Nanoquímica Ambiental Departamento de Física e Química Faculdade de Engenharia de Ilha Solteira Universidade Estadual Paulista (UNESP) Centro, Avenida Brasil, 56 CAPES: 001

Made available in DSpace on 2020-12-12T01:20:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-05 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) This work has assessed the impact of copper oxide nanoparticles (CuONPs), designed via green route, toward photosynthetic apparatus on aquatic photoautotrophic organisms. In order to filling knowledge gaps, in vitro and in vivo assays were performed, using cyanobacterial phycocyanin (C-PC) from Arthrospira platensis and Lemna valdiviana plants (duckweed), respectively. Impairment in light energy transfer became evident in C-PC exposed to CuONPs, giving rise to an increase of light absorption and a suppression of fluorescence emission. Fourier transform infrared spectroscopy (FTIR) results showed that C-PC structures might be altered by the nanoparticles, also revealed that CuONPs preferably interacts with -NH functional groups. The data also revealed that CuONPs affected the chlorophyll a content in duckweed leaves. In addition, photosystem II (PSII) performance was significantly affected by CuONPs, negatively impacting the PSII photochemical network. In summary, the results point out that, even eco-friendly designed, CuONPs may negatively affect the photosynthetic process when accumulated by aquatic photoautotrophs. Natural Resources Program Center for Natural Resources Studies (CERNA) Mato Grosso do Sul State University (UEMS) Applied Optics Group Faculty of Science and Technology Federal University of Grande Dourados (UFGD) Department of Physics and Chemistry School of Engineering São Paulo State University (UNESP) Optics and Photonics Group Institute of Physics Federal University of Mato Grosso do Sul (UFMS) School of Life Science University of Essex Department of Physics and Chemistry School of Engineering São Paulo State University (UNESP)

Differences in physical and structural characteristics of seeds may indicate variability within and between plant populations. In the present study, we performed a close characterization of dimension, shape, and tegument delayed chlorophyll fluorescence in seeds obtained from three species of the genus Annona (Annonaceae), i.e., Annona coriacea, A. montana, A. squamosa. Results showed that studied seeds may be sorted as scalene ellipsoids expressing low values for the seed sphericity. The morphological estimates suggested differences in seed shape for all species. A high correlation was observed between surface area and volume (r2 > 99%) for all the three species suggesting that in addition to structural shape. In addition, we also observed very high positive correlations (Rho = 1.000, p

A simple, inexpensive, highly sensitive, selective, and novel electrochemical method was developed for determination of the Bisphenol A in samples of tap water, blood serum, and urine using a bentonite-modified carbon paste electrode. The graphite, bentonite and the working electrodes (without and chemically modified) were characterized by scanning electron microscopy, infrared absorption spectroscopy, and X-ray diffraction. The electrodes were electrochemically characterized using cyclic voltammetry, square wave voltammetry, and electrochemical impedance spectroscopy. The studied electrochemical variables were: electrode area, standard heterogeneous rate constant, charge transfer coefficient and double-layer capacitance. The bentonite as a sensor modifier had a strong influence on these variables. For the development of the methodology to quantify Bisphenol A, the instrumental parameters (frequency, amplitude, and step potential) and experimental parameters (pH, bentonite quantity) were optimized. The analytical curve to Bisphenol showed a linear response of the oxidation peak current intensity vs. the concentration in the range of 6.8 × 10−10 to 1.5 × 10−8 mol mL−1, with a limit of detection (LOD) of 2.11 × 10−11 mol mL−1 and limit of quantification (LOQ) of 7.04 × 10−11 mol mL−1. Recovery experiments were performed by adding known amounts of Bisphenol A in tap water, blood serum, and urine samples. Recovery rates using the standard addition method were in the range of 97.8–101.8%. The results demonstrated the method feasibility for quantifying Bisphenol A in these samples.

O estudo da filosofia de manufatura enxuta e o tempo de processamento de uma peça são imprescindíveis na redução de desperdícios em uma empresa, neste trata-se de uma proposta de melhorias em seu processo produtivo e a diminuição do lead time, podendo assim reduzir custos e desperdícios e aumentar a confiabilidade dos clientes e sua vantagem competitiva no mercado. Neste contexto, este trabalho apresenta o mapa de fluxo de valor (atual e futuro) de uma família de produtos e identifica oportunidades de melhoria. Trata-se de uma pesquisa aplicada em que a empresa demonstrou um grande estoque intermediário mantido para evitar setups das máquinas e ociosidade do processo seguinte. Com isso, é realizada uma proposta para que o fluxo flua sem paradas ou filas, fazendo com que a remuneração pelo serviço venha mais rápido, com lead time menor. Por fim, foram utilizadas as ferramentas 5W1H e Kanban para propor um mapa no estado futuro com um processo contínuo, apenas um estoque intermediário, mudanças no layout e houve uma redução do lead time em 73,5%, e em 25,4% no tempo de processamento, uma melhoria muito significativa.

Objetivo:Objetiva-se relatar a experiencia de um teste piloto de utilização de check list de cirurgia segura. METODOLOGIA: Trata-se de uma ação realizada por estudantes e docentes de Enfermagem da Universidade Federal do Recôncavo da Bahia e a equipe de enfermagem do Centro Cirúrgico de um hospital escola. O desenvolvimento do teste piloto envolveu a comunicação setorial, a construção de um impresso, a integração do instrumento à prática e uma reunião de equipe. RESULTADOS E DISCUSSÕES: Foram realizados quatro encontros coma participação da equipe, no total de 35 funcionários. Foram aplicados 30 checklists em procedimentos anestéicos-cirúrgicos. Ao final, discutimos os resultados e consideramos que foi possível reconhecer os desafios de segurança no setor, as dificuldades e potencialidades da ação e do instrumento proposto. CONSIDERAÇÕES FINAIS: Essa experiência agregou ensino-assitência-pesquisa e proporcionou o desenvolvimento de estratégias para a segurança do paciente.