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A extensão universitária é definida como um processo educativo, científico e cultural, viabilizando a relação transformadora entre universidade e a sociedade. A Ortodontia é uma área da Odontologia cujos benefícios à saúde estão diretamente ligados à satisfação estética e social do paciente. Objetivou-se, por meio de revisão narrativa da literatura, traçar um panorama acerca da existência de projetos de extensão em Ortodontia, bem como ressaltar sua importância tanto para o ensino quanto para a sociedade. Foi realizada uma busca de estudos que abordassem projetos de extensão em Ortodontia nacionais, utilizando os descritores “Universidade”, “Ortodontia”, “Extensão”, “Saúde Pública”, nas bases de dados Lilacs, SciELO e BVS, dos últimos 20 anos (2000-2020). Foram recuperados 25 trabalhos inicialmente, sendo que após a exclusão dos artigos duplicados, 20 foram selecionados para leitura. Os documentos selecionados passaram por uma triagem final pela leitura completa com o intuito de verificar se atendiam aos critérios de inclusão e exclusão, resultando em 5 artigos. Dentro dessa análise, o que se conclui é que ações que integram extensão e Ortodontia são escassas, predominam nas universidades públicas e apresentam prioritariamente caráter assistencialista à população, embora o aluno participante tenha sua formação diferenciada tanto no quesito clínico quanto no acadêmico.

The vanadium-doped phosphomolybdic acid (H4PMo11VO40) was the most active and selective heteropoly catalyst in one-pot oxidative esterification of benzaldehyde with hydrogen peroxide.

In this work, we report for the first time, the tungstic acid-catalyzed oxidation of terpene alcohols with hydrogen peroxide. This simple, solid, and commercially available catalyst efficiently promoted the conversion of borneol, geraniol and nerol to camphor and epoxide products, respectively. Effects of main reaction parameters, such as catalyst load, the molar ratio of oxidant to the substrate, time, and reaction temperature were investigate. Conversions and selectivity greater than 90% were achieved using 1.0 mol % of H2WO4 after 2 h of reaction at 90°C. The activation energy was equal to 66 kJmol-1. We propose a reaction mechanism based on the experimental results. This solid catalyst was easily recovered and reused without loss of activity. As far as we know, it is the first time that tungstic acid was used as the catalyst in the oxidation reactions of terpene alcohols.

The spread of SARS-CoV-2, the etiological agent of COVID-19, has become a public health problem of international importance. Among the measures to curb its spread is the suspension of classes in educational institutions. Thus, this integrative review aims to provide an overview of the impact of the pandemic on dentistry education in Brazilian institutions. The Medline, LILACS and SciELO databases were searched using descriptors in English and Portuguese. A total of 60 studies were retrieved, with 17 eligible for full reading. Of these, 4 studies met the inclusion and exclusion criteria. It was observed that the emergency remote education (ERE) model through digital tools was the most used remote teaching strategy in Brazilian institutions. ERE allowed the impact of the COVID-19 pandemic to be felt more mildly by the Brazilian academic community, better engaging students and reducing the anxiety of students and teachers. On the other hand, the deficient technological infrastructure in Brazil contributed to difficulty in replacing clinical activities. This fact is further exacerbated by the difficulty of adapting the physical infrastructure of the institutions when planning to return to in-person activities. Despite numerous strategies employed by Brazilian dental education institutions, they were not reflected in the scientific literature in the indexed databases. Thus, there is a need for studies on this topic so that it is possible to disseminate the experiences lived during the pandemic period. A disseminação do Sars-CoV-2, agente etiológico da COVID-19, se tornou um problema de saúde pública de importância internacional. Dentre as medidas para conter seu espraiamento, está a suspensão das aulas em instituições de ensino. Assim, esta revisão integrativa objetiva apresentar um panorama sobre o impacto da pandemia no ensino da Odontologia nas instituições brasileiras. Foram realizadas buscas nas bases de dados Medline, LILACS e SciELO, utilizando-se descritores nas línguas inglesa e portuguesa. Foram recuperados 60 estudos, sendo 17 elegíveis para leitura integral. Destes, 4 estudos atenderam aos critérios de inclusão e exclusão. Observou-se que o modelo de Ensino Remoto Emergencial (ERE) por meio de ferramentas digitais foi a estratégia de ensino não presencial mais utilizada nas instituições brasileiras. O ERE permitiu que o impacto da pandemia de COVID-19 fosse sentido de maneira mais branda pela comunidade acadêmica brasileira, engajando alunos e diminuindo a ansiedade de alunos e professores. Por outro lado, a infraestrutura tecnológica deficiente no Brasil contribuiu para a dificuldade em substituir as atividades clínicas. Fato ainda exacerbado pela dificuldade de adequação da infraestrutura física das instituições durante o planejamento de retorno às atividades presenciais. Apesar de todas as estratégias de superação, desempenhadas pelas instituições brasileiras de ensino odontológico, estas não foram refletidas em literatura científica nas bases de dados indexadas. Assim, enfatiza-se a necessidade de trabalhos sobre esta temática, para que seja possível disseminar as experiências vividas durante o período pandêmico.

Furfural is a platform-molecule of biorefinery highly valuable due to numerous applications in different industries. Furfural acetals are fuel bioadditives, ingredients of fragrances, solvents, paints, and fine chemicals. The condensation of furfural with alcohols requires the presence of an acid catalyst, which should be desirably active, selective, and recyclable. In this work, Keggin heteropolyacids (i.e., HPAs) were converted to solid salts after the partial exchanges of their protons by Cesium ions. This modification makes HPAs insoluble in polar solvents, allowing that they can be easily recycled and reused. The effect of Cesium doping in different HPAs was assessed (i.e., H3PW12O40, H3PMo12O40, H4SiW12O40). Analysis of NH3-TPD (i.e., Ammonia temperature-programmed desorption) allowed to assessment the effect of protons exchange by Cesium on the strength of acidity of catalysts. Among the investigated HPA salts, Cs2.5H0.5PW12O40 was the most active and selective catalyst toward alkyl furfural acetals. An almost total acetalization of furfural with methyl alcohol was achieved after 1 h reaction using 0.0150 mol% of Cs2.5H0.5PW12O40 catalyst. The influences of main reaction parameters were evaluated such as catalyst load, temperature, and sort of alcohol.

Resumo A disfagia tem impactos negativos multidimensionais na vida do paciente disfágico e pode gerar conflitos decisórios relacionados à alimentação. O objetivo deste artigo é revisar a literatura sobre fonoaudiologia, conflitos na tomada de decisão e agentes envolvidos nas deliberações sobre a nutrição desse tipo de paciente. Trata-se de estudo exploratório-descritivo, de revisão integrativa, com análise de conteúdo conforme proposta por Bardin. As bases de dados utilizadas foram: PubMed, Scopus, Web of Science, Cochrane, Embase e Biblioteca Virtual em Saúde. Identificaram-se conflitos envolvendo o fonoaudiólogo, o paciente, a família e a equipe multidisciplinar. Nos artigos selecionados não foi possível identificar uma teoria ou método que fundamentasse a mediação desses conflitos. Não foram encontradas publicações brasileiras que respondessem à pergunta norteadora da revisão. Abstract Dysphagia presents multidimensional negative impacts on the life of dysphagic patients and may generate decision conflicts related to their diet. This is a review of the literature on speech-language therapy, decision conflicts and the agents involved in the decision making process for deliberations related to the nutrition of this type of patient. This is an exploratory and descriptive study, with content analysis as proposed by Bardin. The databases used were PubMed, Scopus, Web of Science, Cochrane, Embase and Virtual Health Library. Conflicts involving the speech-language therapist, the patient, the family and the multidisciplinary team were identified. In the selected articles, no theory or method was identified to support the mediation of these conflicts. No Brazilian publications that answered the guiding question were found. Resumen La disfagia tiene impactos negativos multidimensionales en la vida del paciente disfágico y puede generar conflictos de decisión relacionados con su alimentación. El objetivo de este artículo fue revisar la literatura sobre fonoaudiología, los conflictos de decisión y los agentes involucrados en el proceso de toma de decisiones para las deliberaciones relacionadas con la nutrición de este tipo de pacientes. Se trata de un estudio exploratorio y descriptivo, donde se realizó una revisión integradora con análisis de contenido y categorización por Bardin. Las bases de datos utilizadas fueron: PubMed, Scopus, Web of Science, Cochrane, Embase y Biblioteca Virtual en Salud. Se identificaron los conflictos entre fonoaudiólogo, paciente, familia y equipo multidisciplinario. En los artículos seleccionados no se identificó ninguna teoría o método que sustente la mediación de estos conflictos. No hay publicaciones nacionales que respondan a la pregunta orientadora.

Objetivo: Verificar o desenvolvimento de competências nos estudantes de Odontologia a partir dos ciclos de 2010-2019 do Exame Nacional de Desempenho dos Estudantes (ENADE). Métodos: Foram utilizados os relatórios síntese do ENADE de cada instituição em cada um dos exames compreendidos no período estudado. As questões objetivas das provas foram classificadas de acordo com as competências que avaliaram e o percentual de acerto de cada IES verificado. Resultados: As diferentes competências foram identificadas nas diversas regiões brasileiras, todavia, as médias, embora tenham se desenvolvido durante o período, ainda apontam a necessidade de melhorias nas instituições. Conclusão: Conclui-se que as instituições de ensino superior em odontologia, embora compreendam a importância do desenvolvimento de competências aos estudantes, ainda não possuem todos os métodos e ferramentas de ensino que possibilitarão pleno enriquecimento profissional. A região Nordeste alcançou as melhores médias na maior parte do período estudado. Regiões Sudeste e Sul também se destacaram nas médias, o que pode ser explicado também pelo investimento e visibilidade que as instituições destas regiões possuem.

A green route to oxidize terpenic alcohols (nerol and geraniol) with H2O2 over a solid catalyst was developed. The Dy-doped ZnWO4 catalyst was synthesized by coprecipitation and microwave-assisted hydrothermal heating, containing different dysprosium loads. All the catalysts were characterized through infrared spectroscopy, powder X-ray diffraction, surface area and porosimetry, transmission electronic microscopy image, and n-butylamine potentiometric titration analyses. The influence of main reaction parameters such as temperature, the stoichiometry of reactants, loads, and catalyst nature was assessed. ZnWO4 2.0 mol% Dy was the most active catalyst achieving the highest conversion (98%) and epoxide selectivity (78%) in nerol oxidation. The reaction scope was extended to other terpenic alcohols (i.e., geraniol, borneol, and α-terpineol). The highest activity of ZnWO4 2.0 mol% Dy was assigned to the lower crystallite size, higher surface area and pore volume, higher acidity strength and the greatest dysprosium load.

The activity of metal nitrate catalysts was investigated in the oxidative esterification reactions of benzaldehyde with hydrogen peroxide. Several types of metal nitrates (alkaline, alkaline earth, and transition metals) were evaluated as catalysts. Among the assessed salts, Fe(NO3)3 was the most efficient catalyst toward the formation of the target product (i.e., benzoic alkyl ester). In methyl alcohol, benzaldehyde was selectively oxidized to benzoic acid and then esterified to methyl benzoate. The efficiency of the catalyst was correlated with its higher Lewis acidity character, which was established through the pH measurements of methanolic solutions of the soluble metal nitrate salts. The influence of main variables of the reaction, such as catalyst load, temperature, and reactant stoichiometry, was investigated. The size of the carbon chain and steric hindrance played an essential role in the reaction selectivity. While methyl and ethyl alcohols selectively provided ester as the main product (ca. 70–75%) and acetal as the subproduct, the other alcohols gave ester, hemiacetal, and benzoic acid, which was formed in the least amount. The use of an inexpensive catalyst, a green oxidant, mild conditions, and short reaction times were the positive aspects of this one-pot process. The high TON (ca. 900) is evidence of the high catalytic activity of Fe(NO3)3. It is noteworthy that this methodology does not rely upon ligands and other additives.

The activity of the sodium salts of vanadium-doped phosphomolybdic acid was assessed in the oxidative esterification reaction of benzaldehyde with hydrogen peroxide in alkyl alcohol solutions. The effect of main reaction parameters, such as temperature, catalyst load, vanadium doping level, and reactant stoichiometry, on the conversion and reaction selectivity was investigated. Among the tested heteropoly salts, Na4PMo11VO40 was the most active and selective catalyst, achieving almost complete conversion of benzaldehyde and high ester selectivity regardless of the alcohol investigated. The efficiency of the catalyst was correlated with its vanadium content. The size of the carbon chain of alcohol and the steric hindrance on the hydroxyl group played a key role in the reaction selectivity. While methyl and ethyl alcohols selectively provided the ester as the main product (ca. 90–95%) and benzoic acid as a subproduct, the other alcohols also afforded acetal, a condensation product, and benzaldehyde peroxide, an oxidation reaction intermediate, as secondary products. The use of an inexpensive, environmentally benign, and atom-efficient oxidant, mild conditions, and short reaction times were the positive aspects of this one-pot process.

In this work, the catalytic activity of the transition metal-substituted potassium silicotungstate salts (i.e. K8-nSiMn+W11O39 (Mn+ = Cu2+, Co2+, Ni2+, Zn2+ and Fe3+) was investigated on the oxidation reactions of the terpene alcohols with H2O2 aqueous solution. The metal-substituted silicotungstate salts were easily synthesized in one-pot reactions of the precursor metal solutions (i.e. Na2WO4, Na2SiO3 and MCln) with KCl added in stoichiometric amount; after this precipitation step, the solid heteropoly salts were filtered and dried in an oven. This procedure of synthesis avoids multi-step processes that starts from the pristine heteropolyacid. The substituted metal heteropoly salts were characterized by infrared spectroscopy, measurements of the specific surface area (BET) and porosimetry by isotherms of adsorption/desorption of N2, X-rays diffraction, thermal analyses, dispersive X-rays spectroscopy, scanning electronic microscopy. The acidity strength was estimated by potentiometric titration with n-butylamine. All the salts were evaluated as catalysts in terpenic alcohols oxidation reactions with H2O2. The K5SiFeW11O39 was the most active and selective catalyst toward oxidation products. The impacts of the main reaction variables such as catalyst concentration, temperature, oxidant load, and nature of the terpene substrate were assessed. The highest activity of the K5SiFeW11O39 catalyst was assigned to the highest Lewis acidity.

The activity of the palladium salt catalysts was investigated on the benzaldehyde reactions with H2O2. The PdCl2 salt was the most efficient catalyst for the formation of the goal products. In CH3OH, benzaldehyde was selectively oxidized to benzoic acid and posteriorly esterified to methyl benzoate. In this process, the reaction of the PdCl2 catalyst with aqueous H2O2 provided H+ ions, which also promoted the esterification and acetalization reactions. The oxidant load played a key role in the selectivity controlling; while a large excess (9:1) gave benzoic acid (90%), with a lower ratio (3:1), acid and ester were formed with selectivity of 58 and 35%, respectively. With H2O2 at an equimolar ratio, the Pd(0) reduced the benzaldehyde to benzyl alcohol (30%). In absence of the oxidant, PdCl2 (2.5 mol %) condensated benzaldehyde and alcohol to acetal (90%). Therefore, PdCl2 directly catalyzed the oxidation and reduction reactions, and participated in acid-catalyzed reactions (i.e., condensation and esterification), generating H+ ions, demonstrating to be a highly versatile catalyst. An adequate adjusting of reaction conditions allowed to control the reaction selectivity toward the desired products (i.e., benzoic acid or ester benzyl, acetal, or benzyl alcohol).

In this work, the protons of the Keggin heteropolyacids were exchanged by Lewis acid metal cations generating salts that were evaluated as catalysts on the β-pinene etherification with alkyl alcohols. The Fe(III) phosphotungstate salt (i.e. FePW12O40) was the most active and selective catalyst toward the formation of α-terpinyl methyl ether, the main reaction product. The activity of FePW12O40 catalyst was higher than their precursors of synthesis (i.e. H3PW12O40, Fe(NO3)3), other Fe(III) heteropoly salts (i.e. FePMo12O40 and Fe4/3SiW12O40), and heteropoly salts of different Lewis acids (i.e. AlPW12O40, Cu3(PW12O40)2). The effects of the main variables of reaction such as temperature, catalyst load, and alcohol nature were assessed. The Fe(III) cation, as well as the phosphotungstate anion, showed to be essential to the formation of the goal-product (α-terpinyl alkyl ether).

In this work, we describe the use of iron (III) silicotungstate as a catalyst for the synthesis of solketal, a fuel bioadditive, from glycerol and acetone. A high yield of solketal was achieved in ...

In this work, cesium partially exchanged Keggin heteropolyacid (HPA) salts were prepared, characterized, and evaluated as solid catalysts in monoterpenes etherification reactions with alkyl alcohols. A comparison of the activity of soluble HPAs and their insoluble cesium salts showed that among three different Keggin anions the phosphotungstate was the most efficient catalyst. Assessments on the effects of the level of the protons exchange by cesium cations demonstrated that Cs2.5H0.5PW12O40 solid salt was the most active and selective phosphotungstate catalyst, converting β-pinene to α-terpinyl methyl ether. The influences of the main reaction parameters such as reaction temperature, time, catalyst load, substrate nature (i.e., alcohols and monoterpenes) were investigated. We have demonstrated that the simultaneous presence of the cesium ions and protons in the catalyst plays an essential role, being the 2.5–0.5 the optimum molar ratio. The Cs2.5H0.5PW12O40 salt was efficiently recovered and reused without loss of catalytic activity.

In this work, efficient solid acid catalysts were obtained from the stoichiometric reactions of Keggin heteropolyacids with SnSO4 and evaluated in the etherification reactions of glycerol with tert...

In this work, we describe a new one-pot synthesis route of valuable linalool oxidation derivatives (i.e., 2-(5-methyl-5-vinyltetrahydrofuran-2-yl propan-2-ol) (1a)), 2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol (1b) and diepoxide (1c), using a green oxidant (i.e., hydrogen peroxide) under mild conditions (i.e., room temperature). Lacunar Keggin heteropolyacid salts were the catalysts investigated in this reaction. Among them, Na7PW11O39 was the most active and selective toward oxidation products. All the catalysts were characterized by FT-IR, TG/DSC, BET, XRD analyses and potentiometric titration. The main reaction parameters were assessed. Special attention was dedicated to correlating the composition and properties of the catalysts and their activity.

In this work, we have assessed the activity of various Keggin heteropolyacid (HPA) salts in a new one-pot synthesis route of valuable products, which were obtained from the oxidation of terpenic alcohols (i.e., aldehyde, epoxide, and diepoxide), using a green oxidant (i.e., hydrogen peroxide) at mild conditions (i.e., room temperature). Lacunar Keggin HPA sodium salts were the goal catalysts investigated in this reaction. Starting from the HPAs (H3PW12O40, H3PMo12O40, and H4SiW12O40), we synthesized lacunar sodium salts (Na7PW11O39, Na7PW11O39 and Na8SiW11O39) and a saturated salt (Na3PW12O40). All of them were investigated in oxidation reactions in a homogeneous phase with nerol as a model molecule. Na7PW11O39 was the most active and selective towards the oxidation products. All the catalysts were characterized by FT-IR, TG/DSC, BET, XRD, and SEM-EDS analyses and potentiometric titration. The main reaction parameters were assessed. Geraniol, α-terpineol, β-citronellol and borneol were also successfully oxidized. Special attention was dedicated to correlating the composition and properties of the catalysts with their activity.

In this paper, we have described a novel route to produce 5-hydroxymethylfurfural (HMF), a valuable platform-molecule obtained from biomass, using transition metal-exchanged Keggin heteropolyacid salts as catalysts, in microwave-assisted reactions carried out in a water-ethyl acetate biphasic system. To avoid the use of homogenous Brønsted acid catalysts, which are corrosive and difficult to be reused, we have exchanged the protons of the Keggin heteropolyacids by transition metal cations. These salts were evaluated in the fructose dehydration, being the Cu3/2PW12O40 the most active and selective catalyst, achieving 81 % of HMF yield, after 15 min reaction at 413 K under microwave irradiation (MWI). The effects of metal cation, anion, and heteropolyanion present in the catalyst were evaluated. The greatest efficiency of Cu3/2PW12O40 was attributed to its high Lewis acidity strength, which allows that it coordinate with water molecules, consequently generating H3O+ ions in the reaction medium. Even though the catalyst has been water-soluble, it was easily reused removing the extracting phase, and adding a new load of the substrate to the remaining aqueous phase. This way, it was successfully reused without loss activity.

The activity of the sodium salts of vanadium-doped phosphomolybdic acid was assessed in the oxidative esterification reaction of benzaldehyde with hydrogen peroxide in alkyl alcohol solutions. The effect of main reaction parameters, such as temperature, catalyst load, vanadium doping level, and reactant stoichiometry, on the conversion and reaction selectivity was investigated. Among the tested heteropoly salts, Na

A popularização do uso de redes sociais online como plataformas para o debate político trouxe novos desafios como a propagação indevida de propagandas eleitorais. Por um lado, os eleitores usam as redes sociais para interagir, buscar informações e conhecer seus candidatos. Por outro lado, surgiram verdadeiros palanques digitais para candidatos difundirem suas ideias, atacar adversários e pedir votos. Dessa forma, pré-candidatos podem usar as plataformas para pedir voto fora do período eleitoral, prática conhecida como propaganda eleitoral antecipada. Apesar de existir legislação sobre isso, a falta de ferramentas digitais e métodos de detecção dessa prática pode ser explorada. Neste contexto, este trabalho apresenta uma metodologia para auxiliar a detecção desse tipo de propaganda. Nós coletamos e caracterizamos dados do Twitter e Facebook durante três períodos eleitorais brasileiros (2016, 2018 e 2020), e apresentamos desafios e descobertas importantes sobre o uso das redes sociais para realização dessas propagandas.

Biomass is an attractive source of carbohydrates that can be converted to fuels and fine chemicals. Acid-catalyzed alcoholysis of biomass derivatives provides alkyl levulinates, which are fuel bioadditives, intermediates in the synthesis of drugs and agrochemicals. In this work, we developed a one-pot route to obtain alkyl levulinates using Sn(II) exchanged Keggin heteropolyacids (i.e., H3PW12O40, H3PMo12O40, and H4SiW12O40) as catalysts, in alcoholysis reactions of various carbohydrates. All the catalysts were characterized by FT-IR, XRD, EDS/SEM, TG/DSC, and BET analysis. The tin(II) silicotungstate was the most active and selective catalyst. After 2 h of reaction carried out at 423 K, an almost complete conversion was achieved on the ethanolysis of the fructose, sucrose and inulin, which gave high yields of ethyl levulinate (ca. 78, 71 and 61 mol%, respectively). In all reactions, 5-ethoxymethylfurfural was always the secondary product. Maltose, galactose, and glucose were almost unreactive. The effects of main parameters of reaction, such as temperature, catalyst load, and type of alcohols were assessed. The Sn2SiW12O40 catalyst was easily recovered and successfully reused for 7 cycles, without loss activity.