The Effect of Aluminium Surface Treatments on the Bonding Properties of Silica-Modified Epoxy Adhesive Joints: A Statistical Approach

A full factorial design is carried out to investigate the effects of different surface treatments, the inclusion of silica microparticles and the use of wash primer on the apparent shear strength and adherent strength of single-lap aluminium joints. Scanning electron microscopy, surface energy and roughness measurements are performed to characterise the aluminium surface. The results show that the use of wash primer decreases the apparent shear strength of the joints significantly. The cohesive failure of the primer is the main cause of the reduction in strength. On the other hand, the inclusion of 10 wt.% of silica microparticles in the adhesive layers increases the shear strength by 26%. Surfaces treated with NaOH for one minute, without using a wash primer, result in the most resistant joint. In contrast to the apparent shear strength, adherent strength is most effective when only degreasing is considered

NPK fertilization experiments on corn in Minas Gerais state

Ensaios de adubação NPK na cultura do milho foram realizados no Estado de Minas Gerais nos anos agrícolas de 1967/68 a 1969/70, através de convênio celebrado entre o Instituto de Pesquisa Agropecuária do Centro-Oeste/Banco Nacional de Desenvolvimento Econômico/Associação Nacional para Difusão de Adubos. Os experimentos, em número de 23, foram instalados nas localidades de Patos de Minas, Guaranésia, Pains, Passos, Guaxupé, Rosário de Minas e Coronel Pacheco, tendo os solos sidos previamente analisados e identificados. O delineamento experimental adotado foi o fatorial 3x3x3 com confundimento total da interação NPK, grupo W. Os níveis dos nutrientes estudados, em kg/ha, foram 0, 60 e 120 para N e P2O5 e 0, 30 e 60, para K2O tendo sido utilizado em todos os ensaios o milho hibrido duplo Hmd 6999 B. A análise da variância e o método de Mitscherlich foram aplicados na interpretação dos resultados, juntando-se os dados de produção referentes a solos do mesmo grande grupo. Na aplicação do método de Mitscherlich tomaram-se os preços médios do milho e dos adubos relativos a 1970, publicados pelo Boletim do Departamento de Estudos Rurais da Secretaria de Estado da Agricultura de Minas Gerais. Os solos Latossolo Roxo Eutrófico, Laterítico Bruno-avermelhado, Mediterrânico Vermelho-amarelo e Aluvião mostraram efeito significativo para nitrogênio, com doses econômicas estimadas em 150, 75, 73 e 143 kg/ha, respectivamente. O "intergrade" Podzólico Vermelho-amarelo X Laterítico Bruno-avermelhado, o Latossolo Vemelho-escuro fase cerrado e o Latossolo Vermelho-amarelo Podzólico, apesar de terem apresentado efeito significativo para nitrogênio, não mostraram condições para estimular as doses econômicas. Os solos Laterítico Bruno-avermelhado, Mediterrânico Vermelho-amarelo, Latossolo Vermelho-escuro fase cerrado e Aluvião indicaram efeito significativo para fósforo, com doses económicas estimadas em 113, 81, 111 e 11 kg/ha, respectivamente. Para o Latossolo Vermelho-amarelo Podzólico verificou-se efeito significativo para fósforo, não tendo sido possível estimar a dose econômica. O solo Latossolo Vermelho-amarelo Podzólico mostrou efeito significativo para potássio, com a dose econômica estimada em 89 kg/ha. As respostas obtidas para fósforo confirmaram os resultados analíticos de solos.NPK field experiments on corn were carried out in the State of Minas Gerais during 1967/70 under an agreement signed by IPEACO/BNDE/ANDA. The experiments, 23 in total, were conducted at seven different sites in Minas Gerais: Patos de Minas, Guaranésia, Pains, Passos, Guaxupé, Rosário de Minas and Coronel Pacheco. Soils in all experimental areas were chemically analysed and classified. The experimental design used was 3x3x3 factorial with interaction for NPK totally confounded, group W. Fertilizers were applied at rates of 0, 60, 120 kg N/ha; 0, 60, 120 kg P2O5/ha; 0, 30, 60 kg K2O/ha. Hmd 6999 B double cross hybrid corn was used in all experiments. Analysis of variance and the Mitscherlich method of economic analysis were used in interpreting the results. For the analysis, results from the same great soil group were combined. In applying the Mitscherlich method the average prices for corn and fertilizers in 1970, published by "Departamento de Estudos Rurais" of the Secretaria de Estado da Agricultura de Minas Gerais", were used. The experiments on the "Roxo" Eutrofic Latosol, the Reddish-brown Lateritic soil, the Yellow Mediterranian soil and the Aluvial soil show significant effects for nitrogen, with economic returns from 150, 75, 73 and 143 kg N/ha, respectivelly. Even though the experiments on the Yellow-red podzolic intergrade, the Reddish-brown Lateritic soil, the Dark Red Latosol (Cerrado phase) and the Yellow-red Podzolic Latasol showed significant effects for nitrogen, conditions were not provided for estimating economic levels. The experiments on the Reddish-brown Lateritic soil, the Yellow-red Mediterranian soil, the Dark Red Latosol (Cerrado phase), and the alluvial soil responded significantly to phosphorus, economic levels were 113, 81, 111, and 97 kg P2O5/ha, respectively. A significant effect for phosphorus was found for the Yellow Red Podzolic. However, it was impossible to check the economic response level on this soil. The experiment on the Yellow Red Podzolic Latosol responded significantly to potassium and the economic level was 89 kg K2O/ha. Responses obtained with phosphorus fertilization correlate with soil analysis for this element

Evaluation of in vitro Antifungal Activity of Xylosma prockia (Turcz.) Turcz. (Salicaceae) Leaves Against Cryptococcus spp.

Cryptococcus species are responsible for important systemic mycosis and are estimated to cause millions of new cases annually. The available therapy is limited due to the high toxicity and the increasing rates of yeast resistance to antifungal drugs. Popularly known as “sucará,” Xylosma prockia (Turcz.) Turcz. (Salicaceae) is a native plant from Brazil with little information on its pharmacological potential. In this work, we evaluated in vitro anticryptococcal effects of the leaf ethanolic extract of X. prockia and its fractions against Cryptococcus gattii and Cryptococcus neoformans. We also evaluated phenotypic alterations caused by ethyl acetate fraction (EAF) (chosen according to its biological results). The liquid chromatography–mass spectrometry (LC-MS) analysis of EAF demonstrated the presence of phenolic metabolites that belong to three structurally related groups as majority compounds: caffeoylquinic acid, coumaroyl-glucoside, and caffeoyl-glucoside/deoxyhexosyl-caffeoyl glucoside derivatives. The minimum inhibitory concentration (MIC) values against C. gattii and C. neoformans ranged from 8 to 64 mg/L and from 0.5 to 8 mg/L, for ethanolic extract and EAF, respectively. The EAF triggered an oxidative burst and promoted lipid peroxidation. EAF also induced a reduction of ergosterol content in the pathogen cell membrane. These effects were not associated with alterations in the cell surface charge or in the thermodynamic fingerprint of the molecular interaction between EAF and the yeasts evaluated. Cytotoxic experiments with peripheral blood mononuclear cells (PBMCs) demonstrated that EAF was more selective for yeasts than was PBMCs. The results may provide evidence that X. prockia leaf extract might indeed be a potential source of antifungal agents.Fil: Folly, Mariany L. C.. Universidade Federal de Juiz de Fora; BrasilFil: Ferreira, Gabriella F.. Universidade Federal de Juiz de Fora; BrasilFil: Salvador, Maiara R.. Universidade Federal de Juiz de Fora; BrasilFil: Sathler, Ana A.. Universidade Federal de Juiz de Fora; BrasilFil: da Silva, Guilherme F.. Universidade Federal de Juiz de Fora; BrasilFil: Santos, Joice Castelo Branco. Ceuma University; BrasilFil: Santos, Julliana R. A. dos. Ceuma University; BrasilFil: Nunes Neto, Wallace Ribeiro. Ceuma University; BrasilFil: Rodrigues, João Francisco Silva. Ceuma University; BrasilFil: Fernandes, Elizabeth Soares. Ceuma University; BrasilFil: da Silva, Luís Cláudio Nascimento. Ceuma University; BrasilFil: de Freitas, Gustavo José Cota. Universidade Federal de Minas Gerais; BrasilFil: Denadai, Ângelo M.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: Rodrigues, Ivanildes V.. Universidade Federal de Juiz de Fora; BrasilFil: Mendonça, Leonardo M.. Universidade Federal de Juiz de Fora; BrasilFil: Monteiro, Andrea Souza. Ceuma University; BrasilFil: Santos, Daniel Assis. Universidade Federal de Minas Gerais; BrasilFil: Cabrera, Gabriela Myriam. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad de Microanálisis y Métodos Físicos en Química Orgánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Unidad de Microanálisis y Métodos Físicos en Química Orgánica; ArgentinaFil: Siless, Gastón Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad de Microanálisis y Métodos Físicos en Química Orgánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Unidad de Microanálisis y Métodos Físicos en Química Orgánica; ArgentinaFil: Lang, Karen L.. Universidade Federal de Juiz de Fora; Brasi

Doped Semiconductor Nanocrystals: Development and Applications

This chapter aims to show significant progress that our group has been developing and the applications of several doped semiconductor nanocrystals (NCs), as nanopowders or embedded in glass systems. Depending on the type of dopant incorporated in the nanocrystals, the physical, chemical, and biological properties can be intensified. However, it can also generate undesired toxic effects that can potentially compromise its use. Here we present the potential of zinc oxide NCs doped with silver (Ag), gold (Au), and magnesium (Mg) ions to control bacterial diseases in agriculture. We have also performed biocompatibility analysis of the pure and Ag-doped sodium titanate (Na2Ti3O7) NCs in Drosophila. The doped nanocrystals embedded in glassy systems are chrome (Cr) or copper (Cu) in ZnTe and Bi2Te3 NCs for spintronic development nanodevices. Therefore, we will show several advantages that doped nanocrystals may present in the technological and biotechnological areas

Red Propolis Antifungal Action on Species of Candida of the Oral Cavity

Introduction: propolis is a substance that has aroused the interest of many researchers because of its numerous therapeutic properties, antibacterial and antifungal.Objectives: identifying the species of Candida and evaluate the antifungal effect of red propolis yeast oral cavity.Method: this is a clinical in vitro study with saliva samples collected from 152 patients treated at the dental office of the Family Health Strategy in the city of São Bento-PB. The identification of Candida species was made through the Chrom Ãgar Candida. The antifungal activity of the propolis extract was analyzed in four different concentrations: 100%, 75%, 50% and 25%, through the agar diffusion test.Results: The most prevalent species was C. albicans; antifungal action as to the concentration of 25% of the propolis extract was that apparently demonstrated greater efficacy, compared to the highest concentration.Conclusion: The inhibitory effect of propolis against Candida may have been influenced by the concentration of alcohol present in the extract. To test this hypothesis suggests that search is performed with extracts of propolis and at the same time with the alcohol, in both concentrations and different environmental conditions. This study offers subsidies for other professionals employ different methodologies and propolis concentrations with other substances in order to test the antimicrobial action of these

Data standardization of plant–pollinator interactions

Background: Animal pollination is an important ecosystem function and service, ensuring both the integrity of natural systems and human well-being. Although many knowledge shortfalls remain, some high-quality data sets on biological interactions are now available. The development and adoption of standards for biodiversity data and metadata has promoted great advances in biological data sharing and aggregation, supporting large-scale studies and science-based public policies. However, these standards are currently not suitable to fully support interaction data sharing. Results: Here we present a vocabulary of terms and a data model for sharing plant–pollinator interactions data based on the Darwin Core standard. The vocabulary introduces 48 new terms targeting several aspects of plant–pollinator interactions and can be used to capture information from different approaches and scales. Additionally, we provide solutions for data serialization using RDF, XML, and DwC-Archives and recommendations of existing controlled vocabularies for some of the terms. Our contribution supports open access to standardized data on plant–pollinator interactions. Conclusions: The adoption of the vocabulary would facilitate data sharing to support studies ranging from the spatial and temporal distribution of interactions to the taxonomic, phenological, functional, and phylogenetic aspects of plant–pollinator interactions. We expect to fill data and knowledge gaps, thus further enabling scientific research on the ecology and evolution of plant–pollinator communities, biodiversity conservation, ecosystem services, and the development of public policies. The proposed data model is flexible and can be adapted for sharing other types of interactions data by developing discipline-specific vocabularies of termsinfo:eu-repo/semantics/publishedVersio