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Influence of Crystallization Temperature on the Leakage Current and Photovoltaic Response of BiFeO₃ Thin Films
No full textA ferrita de bismuto (BiFeO3) é um material multiferroico com propriedades fotovoltaicas com potencial para desenvolver novos conceitos de dispositivos fotovoltaicos além da tecnologia do silício, apesar da baixa eficiência de conversão de energia fotovoltaica. Neste trabalho, filmes finos de BiFeO3 foram preparados com objetivo de estudar o efeito da temperatura de cristalização sobre as suas propriedades elétricas e fotovoltaicas. O estudo foi conduzido com base em medidas de corrente-voltagem (I-V) e corrente fotovoltaica em função do tempo I(t) obtidas no escuro e sob iluminação com luz monocromática verde (λ = 532 nm) para amostras cristalizadas a 580, 600, 620 e 640 °C por 30 min, e para um diodo semicondutor comercial. As curvas I-V indicaram um comportamento semicondutor típico para o diodo comercial e um mecanismo ôhmico de condução para campos elétricos abaixo de 25 kV/cm para todos os filmes estudados no escuro e sob iluminação. As correntes fotovoltaicas obtidas para os filmes de BiFeO3 cristalizados a 580 e 600 °C foram I(t)>0, enquanto para os filmes cristalizados a 620 e 640 °C foram I(t) 0, while for the films crystallized at 620 and 640 °C they were () < 0, suggesting a p-type and n-type semiconductor behavior, respectively
Analysis of photovoltaic plants and their operation in distributed generation
No full textNeste trabalho são apresentados componentes que compõem uma UFV (Usina Fotovoltaica), sua topologia e seu modo de operação, definição de GD (Geração Distribuída), geração remota, bem como o impacto dessa aplicação na matriz energética no Brasil e no mercado de energia. Neste é analisada uma UFV de 2,7 MWp e seu desempenho em determinado período, bem como os fatores que influenciam na geração, como irradiância, sujidade, umidade, temperatura ambiente, temperatura dos módulos. Por fim, este estudo tem como objetivo detalhar toda a operação de uma UFV, todos seus equipamentos, e sua operação em geração distribuída no Brasil.This work presents components that make up a PVU (Photovoltaic Plant), its topology and mode of operation, definition of DG (Distributed Generation), remote generation, as well as the impact of this application on the energy matrix in Brazil and on the energy market. A 2.7 MWp PVU will be analyzed to see how it performs over a given period, as well as the factors that influence generation, such as irradiance, dirt, humidity, ambient temperature and module temperature. Finally, this study aims to detail the entire operation of a PUV, all its equipment and its operation in distributed generation in Brazil
A Brazilian Empire Police Delegate: Slavery and public security in the trajectory of Francisco Maria de Souza Furtado de Mendonça (1813-1890)
No full textA segurança tornou-se um dever de Estado no Brasil com a outorga da Constituição do Império, em 1824. Diferentemente de outras nações, o surgimento da Polícia e da segurança pública no Brasil se deu numa época em que vigorava a escravidão de africanos e descendentes. Em meio aos momentos que marcaram a formação da Polícia imperial, constaram em diferentes províncias e em muitos documentos as providências tomadas pelas autoridades policiais diante de escravos, libertos e os chamados africanos livres. O objetivo central desta investigação é contribuir com o ensino e a pesquisa da história da polícia e da segurança pública no Brasil Império ao conhecer e dar a conhecer a trajetória do Delegado Francisco Maria de Souza Furtado de Mendonça (1813-1890), nascido em Angola, África. Polícia e segurança pública são temas relativamente novos na historiografia brasileira e o conhecimento sobre o Brasil Império pode ser consideravelmente enriquecido a partir de novos estudos e pesquisas sobre a polícia, o policiamento e os agentes policiais atuantes nesse período. Uma das primeiras atividades do Delegado Furtado foi conduzir interrogatórios a africanos que teriam desembarcado ilegalmente no Brasil. Ele teria sido rigoroso no cumprimento da lei que determinava a “repressão” contra o tráfico e de outras leis que diziam respeito à escravidão em vigor no país, o que lhe rendeu diversas inimizades. As ações desse agente da Polícia imperial, bem como as relações mantidas por ele no período, como a que estabeleceu com Luiz Gama (1830-1882), são desconhecidas tanto do público especializado, quanto do público em geral. Até o momento. Esta pesquisa buscará na biografia dessa autoridade policial elementos, documentos e reflexões para acrescentar ao conhecimento da história da polícia no Brasil imperial
Singularidades de Thom-Boardman y multiplicidad asociada a extensiones jacobianas iteradas
No full textEste trabalho está estruturado em torno de três objetivos fundamentais. O primeiro consiste em definir e caracterizar as singularidades de Thom-Boardman no espaço dos jatos. Essas singularidades estão intrinsecamente ligadas a vetores conhecidos como símbolos de Boardman e a um tipo especial de germes. O segundo objetivo foca na definição da multiplicidade de Hilbert-Samuel de um anel quociente, associada a um germe de aplicação na origem e a um símbolo de Boardman fixado. O ideal que define este quociente é denominado extensão jacobiana iterada do germe inicial associado ao símbolo de Boardman. Este é um número que generaliza o número de Milnor de um germe de função na origem. Por fim, o terceiro objetivo busca caracterizar essa multiplicidade para o tipo especial de germes mencionados anteriormente, particularizando para famílias de germes quase-homogêneos, apresentando fórmulas para essa multiplicidade que dependam apenas dos graus e pesos associados.This work is structured around three fundamental objectives. The first consists of defining and characterizing Thom-Boardman singularities in the space of jets. These singularities are intrinsically linked to vectors known as Boardman symbols and to a special type of germs. The second objective focuses on the definition of the Hilbert-Samuel multiplicity of a quotient ring, associated with an application germ at the origin and a fixed Boardman symbol. The ideal that defines this quotient is called the iterated Jacobian extension of the initial germ associated with the Boardman symbol. This is a number that generalizes the Milnor number of a function germ at the origin. Finally, the third objective seeks to characterize this multiplicity for the special type of germs mentioned above, particularizing for families of quasi-homogeneous germs, presenting formulas for this multiplicity that depend only on the degrees and weights associated.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)CAPES: 00
Secondary metabolite profiling of Aristolochia gigantea seeds extract by GC−EI/MS and NMR analysis
No full textAristolochia gigantea (Aristolochiaceae), commonly known as the Brazilian Dutchman’s pipe, is cultivated globally as an ornamental vine, admired for the unique shape of its large flowers. In our ongoing research into the chemical composition of A. gigantea, the ethanol extract from its seeds was fractionated using chromatographic techniques, resulting in the isolation and identification of allantoin, along with the lignans kobusin, eudesmin, and methylarctigenin. The fractions were further analysed by NMR and GC − EI/MS, employing a molecular networking approach and retention index comparison, which led to the annotation of four sterols, eleven aliphatic alcohols, one saturated fatty acid, two unsaturated fatty acids, ten esters of saturated fatty acids, ten esters of unsaturated fatty acids, and one lactone.Institute of Chemistry São Paulo State University (Unesp)Institute of Chemistry São Paulo State University (Unesp
Mitochondrial injury induced by triclopyr in the rat liver
No full textThe herbicide triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) is already considered an environmental problem due to damage caused by incorrect disposal, leaching, and aerial dispersion, which may pose risks to the environment and human health. Studies have evaluated metabolism, absorption, excretion, and active transport but there is no clear information about its mode of action (MoA) and its cytotoxic action potential remains unknown. In this context, mitochondria have been used to assess the toxicity of xenobiotics, for this reason, to identify the toxic mechanism of triclopyr, hepatic mitochondria from Wistar rats were exposed in vitro to different concentrations of triclopyr (0.5–500 µM). There was neither formation/accumulation of reactive oxygen and nitrogen species, nor lipid peroxidation or changes in the mitochondrial antioxidant system, in addition to proper functioning of oxidative phosphorylation and ATP production. Changes were found in NAD(P)H oxidation, membrane potential dissipation and mitochondrial calcium gradient. These results demonstrate that mitochondria suffer damage related to their bioenergetics and redox status but not to their structure when exposed to concentrations of triclopyr considered higher than those described as found in the environment so far.Highlights Triclopyr has a low mitochondrial uncoupling potential. The damage caused to the bioenergetics and redox state of the mitochondria is related to concentrations considered higher than those found in the environment. Even at high concentrations, triclopyr was not able to change the structure of the organelle after exposure. Oxidative phosphorylation and ATP production were not impaired after exposure. NAD(P)H oxidation resulted in potential membrane dissipation and mitochondrial calcium gradient dissipation. Triclopyr does not have RONS-forming properties, as well as it does not peroxide membrane lipids, it preserves membrane sulfhydryl groups and maintains the normality of the GSH/GSSG ratio.Medical School São Paulo State University (UNESP)Center for Evaluation of Environmental Impact on Human Health (TOXICAM)School of Agriculture São Paulo State University (UNESP)Medical School São Paulo State University (UNESP)School of Agriculture São Paulo State University (UNESP
Enhancing off-season maize production through tailored nitrogen management and advanced cultivar selection techniques
No full textContext: Climate change can trigger excessive rainfall, making mechanized soybean harvesting unfeasible. The off-season maize cultivation can benefit from soybean-maize rotation system, inoculated with Bradyrhizobium spp. strains, as a potential biological source of nitrogen (N). To meet the nutritional demand of maize crops, N fertilization management is essential. Recent research has sought to understand how maize cultivars respond to mineral N application. Objective: In this work, we used a modern methodology to select maize cultivars with greater response to different application inputs of mineral N fertilizer, including N derived from soybean crop residues. Methods: We used the Manhattan distance to verify the similarity between the responses of four maize cultivars (30F53VYHR, AG8700 PRO3, B2433PWU, and SYN7G17 TL) that were either unfertilized or fertilized with 40, 80, 120, and 160 kg N ha−1. The Technique for Order of Preference by Similarity to the Ideal Solution method was applied to select the most responsive cultivar. Results and conclusions: Among the four maize cultivars, SYN7G17TL and AG8700PRO3 are more responsive to N fertilizer application in medium and high-fertility agricultural soils, respectively. When soil fertility levels are disregarded, the AG8700PRO3 cultivar has greater potential response to N fertilization, agreeing with previous studies. Significance: The proposed approach is easy to use and adapt and provides an appropriate mechanism for selecting maize cultivars sown in areas with soybean residues, thus contributing to more sustainable planting as it adequately assesses nitrogen management.King Saud UniversityPantanal Editora, MTDepartment of Agronomy Federal University of Mato Grosso do Sul, MSDepartment of Agronomy State University of Mato Grosso do Sul, MSDepartment of Botany and Microbiology Faculty of Science King Saud University, P.O. Box 2455Botany and Microbiology Department Faculty of Science Al-Azhar UniversityDepartment of Integrative Agriculture College of Agriculture and Veterinary Medicine United Arab Emirates University, P.O. Box 15551, Abu DhabiDepartment of Plant Protection Rural Engineering and Soils (DEFERS) São Paulo State University (UNESP), SPIntegrated Molecular Plant Physiology Research Department of Biology University of AntwerpNational Intercultural University of QuillabambaDepartment of Agronomy State University of Maranhão, MADepartment of Agronomy Faculty of Agriculture Mansoura UniversityDepartment of Plant Protection Rural Engineering and Soils (DEFERS) São Paulo State University (UNESP), SPKing Saud University: RSPD2024R67
Sustainable Dry Crude Pomegranate Peel Extract as a Bio-input for Medicinal Gels: A Promising Alternative for Wound Healing
No full textThe sustainable use of pomegranate peel, a by-product of the food industry, is gaining importance in developing pharmaceutical bio-inputs, aligning with circular economy practices and waste reduction. This study explores the application of dry crude pomegranate peel extract (PPE) as a bio-input for medicinal gels with wound healing properties. PPE was extracted via percolation in ethanol and freeze-dried. High-performance liquid chromatography and mass spectrometry identified key bioactive compounds: gallic acid, punicalagin, punicalin, ellagic acid, and citric acid, recognized for their antioxidant, antimicrobial, and healing properties. In vitro assays revealed low hemolytic activity, non-cytotoxicity, significant fibroblast proliferation, and robust antioxidant activity (95.99% 2,2-diphenyl-1-picrylhydrazyl scavenging at 100 µg/mL). A carbomer gel containing 2.5% w/w of the extract effectively promoted wound healing in rats, with performance comparable to that of silver sulfadiazine ointment, while demonstrating no microbial contamination during the process. These findings position PPE as a promising, sustainable, and effective alternative for wound-care pharmacotherapy, addressing both medical needs and environmental sustainability.Pharmaceutical Product Development Laboratory Center of Exact Natural and Health Sciences Federal University of Espírito Santo (UFES)Department of Drugs and Pharmaceutics School of Pharmaceutical Sciences - São Paulo State University (UNESP)Graduate Program in Veterinary Sciences Center for Agricultural Sciences and Engineering Federal University of Espírito Santo (UFES)Graduate Program in Pharmaceutical Sciences Center of Health Sciences Federal University of Espírito Santo (UFES)Department of Pharmacy and Nutrition Center of Exact Natural and Health Sciences Federal University of Espírito Santo (UFES)Department of Drugs and Pharmaceutics School of Pharmaceutical Sciences - São Paulo State University (UNESP
Exploring the Use of Helminthophagous Fungi in the Control of Helminthoses in Horses: A Review
No full textWith the increase in parasite resistance to anthelmintics in horses, it is becoming essential to look for new approaches to helminth control. Helminths not only cause health problems in horses but also generate economic losses. One promising solution is the use of helminthophagous fungi, which act on the larvae and eggs of parasites. These fungi can be incorporated into horse feed, helping to reduce infestations on pasture. This review explores the potential of these fungi as an effective and sustainable tool for controlling worms in horses, promoting animal health and environmental protection.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Department of Veterinary Medicine Federal University of Viçosa—UFV, MGDepartment of Epidemiology and Public Health Federal Rural University of Rio de Janeiro—UFRRJ, RJLaboratory of Experimental Parasitology and Biological Control Vila Velha University—UVV, ESDepartment of Animal Pathology University of Santiago de Compostela—USC, GalíciaSchool of Agrarian and Technological Sciences Universidade Estadual Paulista—UNESP, SPSchool of Agrarian and Technological Sciences Universidade Estadual Paulista—UNESP, S
Campo+: proposal for a web application for rural properity management
No full textO presente trabalho apresenta o desenvolvimento de um aplicativo web para o gerenciamento da produção em propriedades rurais de pequeno e médio porte, utilizando o framework Ruby on Rails. A proposta é criar uma ferramenta que facilite a gestão do pequeno produtor em diferentes atividades agropecuárias, de forma modular, otimizando a administração de tarefas, mão de obra e controle de estoque. Com uma interface intuitiva e funcionalidades como dashboard integrado e relatórios financeiros, o sistema oferece uma visão abrangente e eficiente das operações da propriedade. Desenvolvido seguindo boas práticas de desenvolvimento web, o aplicativo assegura eficiência e usabilidade. Alinhado à evolução digital do setor agropecuário, o sistema se propõe a ser um aliado da Agricultura 4.0, aumentando a produtividade e tornando as operações mais funcionais para diferentes perfis de usuários.The objective of this project was to develop a web application for managing production on small rural properties, utilizing the Ruby on Rails framework. The application is designed to simplify management for small-scale producers across diverse agricultural activities, while enhancing task coordination, labor management, and inventory control. With an intuitive interface and features such as an integrated dashboard and financial reporting, the system offers a comprehensive and efficient view of farm operations. Built following best practices in web development, the solution ensures both performance and ease of use. In line with the digital transformation in agriculture, the application aims to support Agriculture 4.0 by boosting productivity and streamlining operations for users of all backgrounds