Funcionalização de ligas Mg-Zn-Zr por anodização assistida por plasma para aplicação biomédica

Materiais bioabsorvíveis, como ligas de Mg, têm sido estudados com a finalidade de prevenir um novo processo cirúrgico invasivo para retirada de implantes permanentes. A dificuldade em utilizar implantes à base de magnésio e suas ligas é devido a sua alta taxa de corrosão, ocorrendo formação do gás hidrogênio e, consequentemente, uma perda precoce na resistência mecânica do dispositivo. Entretando, para promover o aumento nas propriedades destas ligas, especialmente, quanto a resistência a corrosão e ao desgaste, diferentes técnicas de modificação da superfície têm sido investigadas. A funcionalização de superfícies metálicas pelo processo de anodização assistida por plasma, mais conhecida como PEO, apresentam resultados promissores. Este trabalho tem por objetivo estudar a funcionalização da superfície por anodização assistida por plasma (PEO) visando melhorar a resistência à corrosão e ao desgaste de ligas Mg-Zn-Zr para aplicação como biomaterial. Para isso, duas ligas de Mg-Zn-Zr com teor de 3% e 6% de Zn (ZK30 e ZK60) foram avaliadas quanto a resistência à corrosão, desgaste a seco e tribocorrosão. A liga que apresentou melhores propriedades eletroquímicas e de resistência ao desgaste foi utilizada para a funcionalização da superfície pelo processo PEO. Após, foi realizada a aplicação de um filme híbrido composto de quitosana + GPTMS (Glicidoxipropiltrimetoxisilano) sobre o revestimento obtido por PEO. As amostras funcionalizadas foram avaliadas quanto à resitência ao desgaste e resistência à corrosão e quanto à citotoxicidade. Os resultados obtidos mostraram que a funcionalização por PEO promoveu uma redução significativa na liberação de H2, uma melhora na resistência à corrosão e ao desgaste. Além disso, a atividade celular foi favorecida com a funcionalização por PEO, seguida da aplicação de um filme híbrido composto de quitosana + GPTMS.Bioabsorbable materials, such as Mg alloys, have been studied in order to prevent a new invasive surgical process for removing permanent implants. The difficulty in using implants based on magnesium and its alloys is due to their high rate of corrosion, resulting in the formation of hydrogen gas and, consequently, an early loss in the mechanical strength of the device. However, to promote the increase in the properties of these alloys, especially regarding corrosion and wear resistance, different surface modification techniques have been investigated. The functionalization of metallic surfaces by the plasma-assisted anodizing process, better known as PEO, presents promising results. This work aims to study the surface functionalization by plasma-assisted anodizing (PEO) in order to improve the corrosion and wear resistance of Mg-Zn-Zr alloys for application as a biomaterial. For this, two Mg-Zn-Zr alloys with 3% and 6% Zn content (ZK30 and ZK60) were evaluated for resistance to corrosion, dry wear and tribocorrosion. The alloy that presented the best electrochemical and wear resistance properties was used for the surface functionalization by the PEO process. Afterwards, a hybrid film composed of chitosan + GPTMS (Glycidoxypropyltrimethoxysilane) was applied on the coating obtained by PEO. Functionalized samples were evaluated for wear resistance and corrosion resistance and for cytotoxicity. The results obtained showed that the functionalization by PEO promoted a significant reduction in the release of H2, an improvement in the resistance to corrosion and wear. Furthermore, cellular activity was favored with PEO functionalization, followed by the application of a hybrid film composed of chitosan + GPTMS

Satisfação e lealdade dos visitantes que se deslocam ao município da Póvoa de Lanhoso

Mestrado em IPB-ESTG e ASSOCIAÇÃO DE POLITÉCNICOS DO NORTE (APNOR): Instituto Politécnico do Cávado e do Ave, P. Porto, Instituto Politécnico de Viana do CasteloNos últimos anos, o turismo tornou-se um dos principais impulsionadores da economia global, movimentando milhares de pessoas em todo o mundo. Os turistas procuram cada vez mais experiências agradáveis, o que torna essencial compreender suas necessidades e desejos. A Póvoa de Lanhoso, localizada no coração de Portugal, é conhecida pelo seu rico património histórico, cultural e natural, atraindo visitantes de todo o país e do estrangeiro. O turismo desempenha um papel crucial na governação local, impulsionando o desenvolvimento socioeconómico da região. Desta forma, a presente dissertação surge com o intuito de avaliar o grau de satisfação e de lealdade dos visitantes que se deslocam ao município da Póvoa de Lanhoso. O concelho da Póvoa de Lanhoso destaca-se como destino turístico de excelência, sendo procurado pelas suas paisagens, história, monumentos e gastronomia. Consciente da relevância que as políticas de promoção turística têm para o desenvolvimento do concelho, o Município da Póvoa de Lanhoso, apostou num segmento turístico em forte expansão: o turismo itinerante, cuja adesão vai ganhando expressão entre turistas nacionais e estrangeiros, sobretudo na modalidade do autocaravanismo, tido como um segmento turístico caracterizado por circular todo o ano e não apenas na época estival, com reflexos importantes no comércio e restauração dos locais visitados. Pelos resultados obtidos observou-se que os turistas encontram-se satisfeitos com a experiência de visitar a Póvoa de Lanhoso, ainda que existam vários aspetos a serem melhorados para potencializar de forma mais evidente o turismo na vila.Over the last few years, tourism has become one of the main drivers of the global economy, moving thousands of people around the world. Tourists are increasingly looking for pleasant experiences, which makes it essential to understand their needs and desires. Póvoa de Lanhoso, located in the heart of Portugal, is known for its rich historical, cultural and natural heritage, attracting visitors from all over the country and abroad. Tourism plays a crucial role in local governance, driving the socio-economic development of the region. This dissertation therefore aims to assess the level of satisfaction and loyalty of visitors to the municipality of Póvoa de Lanhoso. The municipality of Póvoa de Lanhoso stands out as a tourist destination of excellence, sought after for its landscapes, history, monuments and gastronomy. Aware of the importance of tourism promotion policies for the development of the municipality, the Municipality of Póvoa de Lanhoso has invested in a booming tourist segment: itinerant tourism, which is gaining popularity among domestic and foreign tourists, especially in the form of motorhome tourism, which is a tourist segment characterized by circulation throughout the year and not just during the summer season, with important repercussions on the commerce and restaurants of the places visited. From the results obtained, it was observed that tourists are satisfied with the experience of visiting Póvoa de Lanhoso, although there are several aspects to be improved to enhance tourism in the town

Public perception of the accounting professional through the movie “The Accountant”

Com o intuito de compreender como a imagem do contador é propagada pela mídia, analisou-se elementos de legitimidade propostos por Suchman (1995) e estereótipos ligados à imagem do contador presentes no filme “O Contador” (2016). A pesquisa caracterizou-se como documental, descritiva e qualitativa. Para a análise e interpretação dos dados, utilizou-se a Análise de Conteúdo categorial proposta por Bardin (2010), sendo que as categorias foram formadas a priori. Evidenciou-se que os elementos de legitimidade estiveram presentes, quanto à legitimidade pragmática, na forma como o contador se veste; no envolvimento em trabalhos criminosos; na demonstração de sua capacidade técnica. Na legitimidade moral, existem dilemas éticos conflitantes nas ações do contador, especialista em dinheiro sujo. Quanto à legitimidade cognitiva, ele é visto como alguém que agrada seus clientes e nem sempre escolhe a profissão por afinidade. Em relação aos estereótipos, observou-se discrepância entre gêneros; dificuldade de relacionamento; falta de senso de humor e que o profissional contábil apresenta raciocínio lógico e matemático apurado e competência em suas funções. Destaca-se, portanto, como contribuições da pesquisa, a elucidação das distorções encontradas sobre a imagem dos contadores em estudos empíricos, em relação ao que é veiculado na mídia, por meio do filme analisado, buscando assim, combater imagens negativas da profissão, ao identificar como elas surgem. Com isso, a área contábil beneficia-se com uma possível mudança na percepção popular da importância dos contadores para as empresas, ao entender que o profissional criminoso, exposto nas mídias atuais, diverge daquele que é exigido pelo mercado de trabalho.With the goal of understanding how the image of accountants is portrayed by the media, we analyzed elements of legitimacy proposed by Suchman (1995) and stereotypes linked to the image of the accountant found in the movie “The Accountant” (2016). The research is documentary, descriptive and qualitative. To analyze and interpret data, we used the Categorical Content Analysis proposed by Bardin (2010), and the categories were determined beforehand. It was found that the elements of legitimacy were present regarding pragmatic legitimacy in the way the accountant dresses, his involvement in criminal activities, the demonstrating of his technical capacity. Regarding moral legitimacy, there are conflicting ethical dilemmas in the actions of the accountant, a specialist in dirty money. Regarding cognitive legitimacy, he is seen as someone who pleases his clients and does not always choose the profession by affinity. Regarding stereotypes, there was a discrepancy between genders, relationship difficulty, lack of sense of humor and that the accounting professional presents accurate logical and mathematical reasoning and competence in their functions. As research contributions, therefore, we can highlight the elucidation of distortions found involving the image of accountants in empirical studies, in relation to what is portrayed by the media, by the movie under analysis, seeking to combat negative images of the profession by identifying how they arise. The accounting field benefits from this with a possible shift in the popular perception of the importance of accountants for companies, by understanding that the criminal professional, exposed in the current media, are different from the professional required by the job market

PRODUCTION OF Colubrina glandulosa SEEDLINGS WITH DIFFERENT MYCORRHIZAL INOCULA

Colubrina glandulosa has potential for reforestation of disturbed areas. Seedlings inoculated with arbuscular mycorrhizal fungi (AMF) can be produced with biosolids from Sewage Treatment Plants. This study aimed to evaluate the response of Colubrina glandulosa seedlings to isolated or mixed inoculation of different AMF species on a biosolid-based substrate under greenhouse conditions. The experimental design was completely randomized, with 32 replicates (seedlings)/treatment and five treatments: (1) control or absence of inoculation (CT); (2) inoculation with Dentiscutata heterogama (DH); (3) inoculation with Gigaspora margarita (GM); (4) inoculation with Rhizophagus clarus (RC); (5) inoculation with the mixture of the three AMF species (MT). We evaluated height and collar diameter of the seedlings at 30, 60, 90, 120, and 140 days after the experiment installation. We evaluated shoot dry biomass (SDM), root dry biomass (RDM), and total dry biomass; SDM / RDM ratio; Dickson Quality Index; relative increments in height, collar diameter, and shoot biomass; nutrient content (N, P, K) in the shoots and roots; efficiency of absorption and utilization of nutrients; rate of root mycorrhizal colonization, at 140 days. In general, the highest values of growth and nutrition variables occurred in the MT treatment, which was recommended, in comparison with CT, DH, GM, and RC. Colonization rates were low (≤ 20 %), regardless of the mycorrhizal inoculum, due to the high levels of phosphorus in the biosolid

Corrosion resistance and tribological behavior of ZK30 magnesium alloy coated by plasma electrolytic oxidation

The rapid bio-corrosion of magnesium-based alloys, the formation of hydrogen gas and, consequently, the premature loss of biomechanical functions hinder their applications as biodegradable implant materials. The corrosion becomes even accelerated, when fretting wear occurs at implant junctions, as a result of repeated disruptions of the magnesium (hydr)oxide layer formed on implant surfaces. To improve the overall performance of these materials in a bio-relevant environment, especially corrosion resistance and wear resistance, in this research, plasma electrolytic oxidation (PEO) was applied to create a coating on a magnesium alloy, ZK30. The resulting gains in corrosion resistance and wear resistance were evaluated. In vitro immersion tests in Hank’s solution at 37 ◦C showed a reduction in hydrogen release from the PEO-treated alloy. The results obtained from applying the scanning vibrating electrode technique (SVET) indicated a decreased susceptibility of the PEO- treated alloy to localized corrosion, accounting for the improved corrosion resistance. In addition, PEO was found to change the surface topography and roughness, in addition to surface chemistry, which contributed to an increased but stable coefficient of friction and a decreased material removal rate, as revealed by the tribological tests with a ball-on-plate configuration. The results indicate an enlarged opportunity of magnesium-based ma-terials for orthopedic applications, where friction and wear are involved, by applying PEO

EFFECT OF MYCORRHIZAL INOCULATION AND SUBSTRATE COMPOSITION ON SEEDLING GROWTH OF TWO ATLANTIC FOREST TREE SPECIES

The search for more efficient biotechnological tools for forest regeneration has increased over the past decades. Mycorrhizal inoculation is a valuable strategy to promote seedling growth, but its efficiency depends on the substrate used. This study aimed to investigate the effects of arbuscular mycorrhizal fungal inoculation and different types of substrates on the growth of Pseudobombax grandiflorum and Apuleia leiocarpa seedlings. Experiments were carried out under greenhouse conditions in a completely randomized 6 × 2 factorial design (six substrates and two inoculation levels) with six replications of 12 treatments. Both species showed similar growth patterns. Plants grown in inoculated substrates composed of 70% Cambisol and 30% bovine manure or 80% Cambisol and 20% Biomix showed improved nutritional status. These substrates had good physical and chemical characteristics (pH and P and N levels), which favored plant development and mycorrhizal symbiosis. P. grandiflorum seedlings showed enhanced growth in inoculated substrate composed of 80% Cambisol and 20% Biomix and in inoculated Cambisol fertilized with P. For A. leiocarpa, the best results were observed for seedlings grown in inoculated substratescomposed of 80% Cambisol and 20% Biomix, 70% Cambisol and 30% bovine manure, or Cambisol fertilized with P

Gas exchange in umbu tree accessions

The objective of this work was to evaluate gas exchanges in umbu tree accessions. A 5 × 7 × 2 split-split plot experiment was carried out in a completely randomized design (five accessions – BRS-68, EPAMIG-05, BGU-61, BGU-75, and BGU-50 × seven evaluation dates × two reading times – 8 a.m. and 2 p.m.) with three repetitions. The lower leaf temperatures recorded in BRS-68 and EPAMIG 05 accessions favor higher net photosynthetic rates, water use efficiency and instantaneous carboxylation efficiency compared to BGU 61 accession. Umbu tree regulates transpiration by reducing stomatal conductance under high vapor pressure deficit, although the tree increases transpiration as a defense strategy against heat stress, even with a reduction in stomatal conductance. High temperatures limit instantaneous carboxylation efficiency, photosynthetic rate, and the ratio of photosynthesis to radiation incident on the leaf. Transpiration varies directly with stomatal conductance, while intrinsic water use efficiency varies inversely with internal CO2 concentration.The objective of this work was to evaluate gas exchanges in umbu tree accessions. A 5 × 7 × 2 split-split plot experiment was carried out in a completely randomized design (five accessions – BRS-68, EPAMIG-05, BGU-61, BGU-75, and BGU-50 × seven evaluation dates × two reading times – 8 a.m. and 2 p.m.) with three repetitions. The lower leaf temperatures recorded in BRS-68 and EPAMIG 05 accessions favor higher net photosynthetic rates, water use efficiency and instantaneous carboxylation efficiency compared to BGU 61 accession. Umbu tree regulates transpiration by reducing stomatal conductance under high vapor pressure deficit, although the tree increases transpiration as a defense strategy against heat stress, even with a reduction in stomatal conductance. High temperatures limit instantaneous carboxylation efficiency, photosynthetic rate, and the ratio of photosynthesis to radiation incident on the leaf. Transpiration varies directly with stomatal conductance, while intrinsic water use efficiency varies inversely with internal CO2 concentration

O Profissional Contábil perante os impactos da internacionalização da Contabilidade / The Accounting Professional in the face of the impacts of the internationalization of Accounting

A internacionalização da contabilidade foi um processo essencial para o bom funcionamento das relações e negociações internacionais, devido tanto à globalização quanto aos avanços tecnológicos.  Esse processo proporcionou muitas melhorias, sobretudo na qualidade e clareza das informações contábeis em um cenário internacional, proporcionando reduções de custos e maior facilidade nas tomadas de decisões. A convergência da contabilidade causou significativas mudanças na estrutura da área contábil, e consequentemente mudaram a forma de atuação do contador, o mercado passou a exigir maior capacitação e sintonia com as mudanças geradas. Dessa forma o objetivo do presente artigo é analisar a posição e perfil do contador para atuar em meio a esse cenário globalizado, bem como evidenciar a importância desse profissional a partir desse cenário. Para isso foi realizado levantamento bibliográfico com as principais mudanças advindas das convergências às normas internacionais de contabilidade, proporcionando embasamento teórico suficiente para etapa de pesquisa junto aos profissionais da área, utilizando o questionário como meio de coleta dos dados. Com base na pesquisa foi possível analisar as percepções dos profissionais que estão atuando na área contábil sobre o impacto da internacionalização da contabilidade em sua atuação

SARS-CoV-2 infection with bilateral intralabyrinthine hemorrhage

A 47-year-old woman presented with the complaint of sudden hearing loss associated with vertigo. Serological testing was positive for IgM and negative for IgG COVID-19 antibodies, with no other associated factors. Magnetic resonance imaging of the brain showed bilateral intralabyrinthine hemorrhage