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Hematological problems are associated with Coronavirus disease 2019 (COVID-19). Respiratory impairment is the higher point studied, although without experimental studies related to the oxygen transport performed by erythrocytes. Therefore, we decided to investigate if erythrocytes from COVID-19 patients have their functionality changed. The case-control study included hospitalized patients with a positive real-time polymerase chain reaction (RT-PCR) result admitted to University Hospital. Volunteers (negative RT-PCR results) were recruited as a control group. Thus, we assessed different erythrocytes parameters, oxidative stress markers, and biophysical studies using whole blood and isolated hemoglobin. We found a decrease of 51% in oxygen uptake and reduced antioxidant enzyme activity in COVID-19 patients compared to controls. Raman spectrometry showed structural changes in the hemoglobin and lipids of the erythrocytes from COVID-19 patients; thus, these results were consolidated with an increase in Young’s modulus in erythrocytes followed by morphology changes. Besides, isolated hemoglobin from COVID-19 patients has a distinct interaction profile using a ligand model compared to the control. COVID-19 leads to structural, functional, and morphological damage to human erythrocytes. Our data showed structural and molecular changes and induction of oxidative stress in erythrocytes by COVID-19, a new perspective on the contribution of erythrocytes to a respiratory commitment in COVID-19.

https://doi.org/10.21577/0103-5053.20230031

How many species of Mollusca are there in Brazil? A collective taxonomic effort to reveal this still unknown diversity
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Machado, Fabrizio M.

; Miranda, Marcel S.

; Salvador, Rodrigo B.

; Pimenta, Alexandre D.

; Côrtes, Mariana O.

; Gomes, Jaime A.J.

; Miyahira, Igor C.

; Agudo-Padrón, Ignacio

; Oliveira, Cléo D.C.

; Caetano, Carlos H.S.

; Coelho, Paulo R.S.

; D’Ávila, Sthefane

; Arruda, Eliane P. de

; Almeida, Sérgio M. de

; Gomes, Suzete R.

; Alvim, Juliana

; Galvão-Filho, Hilton

; L. Ferreira-Júnior, Augusto

; Marques, Rodrigo C.

; Martins, Inês

; Souza, Leonardo S. de

; Arruda, Janine O.

; Cavallari, Daniel C.

; Santos, Sonia B. dos

; Pedro, Natan C.

; Salles, Anna C. de A.

; Dornellas, Ana P.S.

; Lima, Tarcilla C. de

; Amaral, Vanessa S. do

; Silva, Fernanda S.

; Passos, Flávio D.

; Thiengo, Silvana S.

; Leite, Tatiana S.

; Simone, Luiz R.L.

Zoologia (Curitiba)

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2023, Volume 40 elocation e23026

Abstract: En | Text: En | PDF: En

ABSTRACT The expression ‘you need to know to conserve’ is a well-known cliche among biologists. Documenting the richness of a group of organisms is the first step towards understanding biodiversity and preparing efficient conservation plans. In this context, many efforts have been made to quantify the number of species on Earth and estimate the number of species still unknown to science. A few countries have complete and integrated databases estimating the approximate number of species recorded for their territory, particularly in the Global South. In Brazil, a country of continental dimensions, revealing the richness of the second most diverse clade of invertebrates (=Mollusca) has been a goal of taxonomists. Recently, in an unprecedented, collective, and integrated effort among Brazilian malacologists, it was possible to estimate how many valid species of molluscs are there in Brazil. In this effort, more than 30 mollusc experts joined together to update the Taxonomic Catalogue of the Brazilian Fauna (TCBF), a governmental website that allows a quick and real-time updating of all Metazoan. So far, more than 5,000 updates have been made in TCBF, indicating the presence of 3,552 valid species of molluscs in Brazil, distributed among the main clades as follows: Caudofoveata (10 spp.), Solenogastres (6 spp.), Polyplacophora (35 spp.), Scaphopoda (43 spp.), Cephalopoda (92 spp.), Bivalvia (629 spp.) and Gastropoda (2,737 spp.). The present study, in addition to demonstrating for the first time the richness of Brazilian molluscs, also presents the state of the art of this important phylum of invertebrates highlighting its most representative and neglected groups.

https://doi.org/10.1590/s1984-4689.v40.e23026

Phenotypic plasticity in Copaifera langsdorffii Desf. in different forest fragments in São Paulo state, Brazil
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SIQUEIRA, MARCOS VINICIUS B.M.

; SILVÉRIO, GIOVANA HENRIQUE

; CARLOS, JULIANA S.

; TOLEDO, JAYÇA A.M.

; SILVA, CLEBER JOSÉ DA

; PAULA-SOUZA, JULIANA DE

; GALASTRI, NATÁLIA A.

Anais da Academia Brasileira de Ciências

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2023, Volume 95 N. 1 elocation e20210541

Abstract: En | Text: En | PDF: En

Abstract Forest fragments are susceptible to environmental shifts and this demands high phenotypic plasticity of the species growing in these areas. In this context, the objective of the present work was to study the phenotypic plasticity of copaíba (Copaifera langsdorffii Desf.) based on morphological and anatomical metrics of the leaflets of plants from six forest fragments. The leaflets of C. langsdorffii individuals of the different fragments did not show qualitative differences, nonetheless, they demonstrated quantitative plasticity. Stomatal density (p = 0.017), specific leaf area (p = 0.009), palisade parenchyma (p = 0.008) and relative water content (p = 0.002), indicated a high luminous, water and nutritional influence on the development of leaflets. Based on the dry mass of the leaflets and the thickness of the palisade parenchyma, the principal component analysis explained 57.43% of the differences found between the variables. The data presented here provides evidence of the phenotypic plasticity of C. langsdorffii which, although occurring in similar soils, showed significant quantitative differences in its morphoanatomical characters.

https://doi.org/10.1590/0001-3765202320210541

Synthesis and Evaluation of the Antileishmanial Activity of Novel Eugenol Analogs Containing 1,2,3-Triazole Fragments against Intracellular Leishmania braziliensis
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Evangelista, Roberta S.

; Pereira, Larissa C.

; Souza, Luciana Â. de

; Costa, Adilson V.

; Silva, Danilo A. da

; Oliveira, Fabrício M. de

; Vaz, Boniek G.

; Bressan, Gustavo C.

; Fietto, Juliana L. R.

; Teixeira, Róbson R.

Journal of the Brazilian Chemical Society

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2023, Volume 34 N. 12 Pages 1810 - 1824

Abstract: En | Text: En | PDF: En

This investigation describes the synthesis of eugenol analogs presenting 1,2,3-triazole fragments and evaluation of their antileishmanial activity. The alkylation of guaiacol (1) with allyl bromide afforded 1-(allyloxy)-2-methoxybenzene (2) (93% yield). The Claisen rearrangement conducted with 1 gave ortho eugenol (3) (82% yield). Alkylation procedures performed with 3 produced 1-allyl-3-methoxy-2-(prop-2-yn-1-yloxy)benzene (4) (73% yield) and 1-allyl-3-methoxy-2-(pent-4-yn-1-yloxy)benzene (6) (53% yield). The copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) reactions involving alkynes 4 and 6 with different benzylic azides afforded twenty-two eugenol analogs with 1,2,3-triazole functionalities (48-93% yield). We screened the compounds at 10 μmol L 1 against Leishmania braziliensis intracellular amastigotes during macrophage infection. The action of these compounds was compared with the known leishmanicidal drug amphotericin B. None of the analogs were toxic to macrophages at 10 μmol L-1. The cytotoxic concentration at 50% (CC50), effective concentration at 50% (EC50), and selectivity index (SI) were determined to the best compounds 4-((2-allyl-6-methoxy)phenoxymethyl)-1-(4-chlorobenzyl)-1 H-1,2,3-triazole (8c) and 4-((2-allyl-6-methoxy)phenoxymethyl)-1-(4-trifluoromethoxybenzyl)-1 H-1,2,3-triazole (8h). They showed a significant leishmanicidal effect, with EC50 of 28.09 µmol L-1 (8c) and 52.03 µmol L-1 (8h). The SIs were 9.7 for 8c and > 5.7 for 8h. These compounds have the potential as new leishmanicidal agents against L. braziliensis and may represent a starting point for the development of alternative treatments for cutaneous leishmaniasis.

https://doi.org/10.21577/0103-5053.20230073

Periodontal diseases and tooth wear in sheep flocks in the State of Goiás, Brazil
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Martins, Andressa S.

; Silva, Tamires A.

; Athayde, Flávia R.F.

; Saraiva, Júlia R.

; Mendes, Juliana G.

; Cardoso, Maria Vitória S.

; Dutra, Iveraldo S.

; Borsanelli, Ana Carolina

Pesquisa Veterinária Brasileira

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2023, Volume 43 elocation e07367

Abstract: En Pt | Text: En Pt | PDF: En | PDF: Pt

ABSTRACT: Dental and periodontal affections consist of health concerns of great importance in sheep flocks, as they affect the health and welfare of animals and represent one of the main causes of premature slaughter. Studies on the occurrence of these conditions in sheep are scarce in Brazil. The present study aimed to evaluate the prevalence of periodontal diseases and tooth wear in sheep flocks in the State of Goiás. For this, a clinical oral examination was conducted on 325 sheep from seven farms in six municipalities of the State. Periodontal lesions, characterized by gingival recession in at least one incisor tooth, were observed in 48.3% (157/325) of the sheep, while in cheek teeth it occurred in 13.2% (43/325) of the evaluated sheep. Dental wear on cheek teeth was identified in 69.2% (255/325) of the sheep, and 10.7% (35/325) of the ovines showed dental wear on incisor teeth. Sheep older than 36 months had an increase in the frequency of tooth wear. A total of 171 (52.62%) out of the 325 examined sheep had signs of bleeding on probing, which is compatible with gingivitis, and 69 (40.36%) were older than 36 months. Thirty-eight (11.69%) out of the 325 evaluated ovines had gingivitis in all teeth, among which 21 (55.26%) were older than 36 months. Logistic regression analysis allowed the observation that age was associated with the occurrence of gingivitis. Less frequent changes such as periodontal pockets and loss of at least one tooth were also observed in 4.9% (16/325) and 17.8% (58/325) of the sheep, respectively. It indicates that the presence of periodontal diseases and tooth wear is a common occurrence in the evaluated flocks. Therefore, there is a need to include the oral health of sheep in the routine of the farm as an essential preventive measure to improve the quality of life, animal welfare, and zootechnical indices.

RESUMO: As afecções dentárias e periodontais constituem uma preocupação sanitária de grande importância em rebanhos ovinos, uma vez que afetam a saúde e o bem-estar dos animais, e representam uma das principais causas para o abate prematuro. No Brasil, estudos sobre a ocorrência dessas afecções em ovinos são escassos. Assim, o presente estudo teve como objetivo avaliar a prevalência de doenças periodontais e desgaste dentário em rebanhos ovinos no estado de Goiás. Para isso, realizou-se o exame clínico bucal em 325 ovinos em sete propriedades rurais de seis municípios do estado. As lesões periodontais, caracterizadas por recessão gengival em, pelo menos, um dente incisivo, foram observadas em 48,3% (157/325) dos ovinos, enquanto nos mastigatórios ocorreu em 13,2% (43/325) dos ovinos avaliados. O desgaste dentário em dentes mastigatórios foi identificado em 69,2% (255/325) dos ovinos e 10,7% (35/325) dos ovinos apresentaram desgaste dentário em dentes incisivos. Ovinos com idade superior a 36 meses tiveram um aumento na frequência do desgaste dentário. Dos 325 ovinos examinados, 171 (52,62%) apresentaram sinais de sangramento à sondagem, compatíveis com o quadro de gengivite, sendo que 69 (40,36%) apresentaram idade superior a 36 meses. Dos 325 ovinos avaliados, 38 (11,69%) apresentaram gengivite em todos os dentes, dos quais 21 (55,26%) apresentaram idade superior a 36 meses. Pela análise de regressão logística, foi possível observar que a idade mostrou associação com a ocorrência de gengivite. Alterações menos frequentes como a bolsa periodontal e a perda de, pelo menos, um elemento dentário também foram observadas em 4,9% (16/325) e 17,8% (58/325) dos ovinos, respectivamente. Os resultados do presente estudo indicam que a presença doenças periodontais e desgaste dentário é uma ocorrência comum nos rebanhos avaliados. Portanto, enfatiza-se a necessidade de incluir a saúde bucal dos ovinos na rotina da propriedade como uma medida preventiva essencial para melhorar a qualidade de vida e o bem-estar dos animais, bem como os índices zootécnicos.

https://doi.org/10.1590/1678-5150-pvb-7367

Physiological aspects and production of coriander using nutrient solutions prepared in different brackish waters
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Navarro, Franz E. C.

; Santos Júnior, José A.

; Martins, Juliana B.

; Cruz, Ruana I. F.

; Silva, Manassés M. da

; Medeiros, Salomão de S.

Revista Brasileira de Engenharia Agrícola e Ambiental

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nov 2022, Volume 26 N. 11 Pages 831 - 839

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

RESUMO A análise da fluorescência da clorofila é uma das muitas formas de quantificar o dano salino no desempenho fotossintético e na produção agrícola. Assim, o presente estudo teve como objetivo avaliar a eficiência fotoquímica e a produção do coentro, cultivar Verdão em função dos níveis de condutividades elétricas da solução nutritiva e da natureza catiônica. O delineamento experimental foi em blocos ao acaso, em esquema fatorial 4 × 3, com quatro repetições. Os tratamentos consistiram na exposição das plantas a quatro condutividades elétricas das soluções nutritivas (CEsn = 1,6; 3,2; 4,8 e 6,4 dS m-1) e três tipos de águas de diferentes naturezas catiônicas (Na+; Ca2+; Mg2+), preparadas com a solubilização de diferentes sais - NaCl, CaCl2.2H2O e MgCl2.6H2O em água de abastecimento da UFRPE (CEa = 0,12 dS m-1). O estudo foi realizado em casa de vegetação entre novembro e dezembro de 2019 no Laboratório de Fertirrigação e Salinidade do Departamento de Engenharia Agronômica da Universidade Federal Rural de Pernambuco. O aumento da condutividade elétrica da solução nutritiva afetou os centros de reação, a atividade fotoquímica, a eficiência da carboxilação e resultou na redução da condutância estomática, da taxa de assimilação de CO2 e, portanto, na produção de biomassa do coentro. Diferentes prevalências catiônicas na água proporcionam diferenças na intensidade do dano salino, sobretudo com o aumento da concentração.

ABSTRACT The analysis of chlorophyll fluorescence is one of many ways to quantify the salt damage to photosynthetic performance and crop production. Thus, the present study aimed to evaluate the photochemical efficiency and production of coriander, cultivar ‘Verdão’, as a function of the electrical conductivity levels of the nutrient solution and the cationic nature. The experimental design was in randomized blocks, in a 4 × 3 factorial scheme, with four replicates. The treatments consisted of four electrical conductivities of the nutrient solutions (ECns = 1.6, 3.2, 4.8, and 6.4 dS m-1) and three kinds of water of different cationic natures (Na+; Ca2+; Mg2+), which were prepared with the dissolution of different salts - NaCl, CaCl2.2H2O, and MgCl2.6H2O in supply water (ECw = 0.12 dS m-1), that is, three predominant cationic natures. The study was carried out in a greenhouse between November and December 2019 at the Fertigation and Salinity Laboratory of the Agricultural Engineering Department of the Universidade Federal Rural de Pernambuco. It was found that the increase in the electrical conductivity of the nutrient solution affected reaction centers, photochemical activity, and carboxylation efficiency and resulted in reductions in stomatal conductance, CO2 assimilation rate, and therefore, in the biomass production of coriander. Different cationic prevalence in water causes differences in the intensity of salt damage, especially with increasing concentration.

https://doi.org/10.1590/1807-1929/agriambi.v26n11p831-839

Tuning the Photocatalytic Activity of Tin Oxide through Mechanical Surface Activation
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Silva, Fernando B. F.

; Silva, Gelson T. S. T. da

; Torres, Juliana A.

; Ribeiro, Caue

Journal of the Brazilian Chemical Society

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jul 2022, Volume 33 N. 7 Pages 725 - 733

Abstract: En | Text: En | PDF: En

Tin oxide (SnO2) nanoparticles were synthesized by the co-precipitation method and mechanically modified by high-energy ball milling. The experimental results demonstrate that the collision with zirconia balls produces slight changes in the crystalline, electronic, morphological, and surface properties of SnO2, which lead to an increase in the redox potential of the energy level and the formation of the hydroxyl group on the SnO2 surface. Moreover, these changes are intensified over the milling up to 90 min, directly affecting the photocatalytic performance, which was monitored by the rate of rhodamine B (RhB) degradation driven by ultraviolet (UV) irradiation. As a result, all ground samples showed better photocatalytic activity than pristine SnO2 (Sn-cop). The maximum degradation of rhodamine B was ca. 75%, achieved with 90 min-milled SnO2 nanoparticles (Sn-M90), compared to the Sn-cop sample induced a 1.67 times higher degradation rate. The reaction mechanism suggests that its better photocatalytic activity may be associated with the higher increased redox potential of the valence and conduction bands and the formation of hydroxyl active sites on the catalyst surface principal oxidizing agent generated. Therefore, we conclude that the ball milling process is an efficient way to induce stable activation of oxide metal for photocatalytic applications.

https://doi.org/10.21577/0103-5053.20220009

Refractory feline sporotrichosis: a comparative analysis on the clinical, histopathological, and cytopathological aspects
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Silva, Francine S.

; Cunha, Simone C.S.

; Moraes, Vanessa A.

; Leite, Juliana S.

; Ferreira, Ana M.R.

Pesquisa Veterinária Brasileira

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2022, Volume 42 elocation e06923

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

RESUMO: A esporotricose é uma infecção fúngica crônica causada por espécies do gênero Sporothrix. A ocorrência de casos refratários ao tratamento de longo prazo, especialmente na região nasal de gatos, alerta para a importância do estudo de sua patogênese. Este estudo teve como objetivo analisar o processo inflamatório das lesões cutâneas de esporotricose felina refratária ao tratamento, por meio de exames citopatológico e histopalógico, e comparar com aspectos clínicos. Treze gatos com lesões cutâneas refratárias ao tratamento com Itraconazol por mais de um ano foram incluídos no estudo. Amostras de lesões cutâneas foram coletadas para análises citopatológicas, histopatológicas e cultura fúngica. Fragmentos de tecidos foram processados e corados pela hematoxilina-eosina (HE) e Prata Metenamina de Grocott (GMS). Duas apresentações clínicas tiveram maior ocorrência: a forma localizada cutânea em animais com bom estado geral e doença estável (n=9, 69,2%); e a forma disseminada cutânea em gatos com estado geral ruim (n=4, 30,8%). A região nasal (84,6%) foi a localização mais frequente das lesões nos gatos com esporotricose refratária ao tratamento. No estudo citopatológico, felinos com menos de duas lesões, e em bom estado geral, (n=9, 69,2%) revelaram ausência ou leve intensidade de leveduras (até 5 leveduras por campo), menor intensidade de macrófagos e neutrófilos, e maior intensidade de células epitelióides, linfócitos, plasmócitos e eosinófilos. Enquanto, (n=4, 30,8%) dos felinos que apresentavam a forma disseminada da esporotricose associada a um estado geral ruim, revelaram acentuada intensidade de leveduras em sua maioria fagocitadas por acentuado número de macrófagos e neutrófilos. Dos animais com bom estado geral, a maioria (n=6, 66,7%) apresentava maior intensidade de eosinófilos. Na histopatologia, o granuloma supurativo mal formado foi o tipo predominante (n=9, 69,2%) nas lesões de esporotricose felina, e (n=4, 30,8%) foram de granulomas bem formados. Granulomas mal formados apresentaram leve a moderada intensidade fúngica (55,6%) nos animais com bom estado geral e lesões localizadas, e acentuada intensidade fúngica (44,4%) nos gatos com a forma disseminada da doença e estado geral ruim. Granulomas bem formados (n=4, 30,7%) apresentaram leve a moderada intensidade de carga fúngica, sendo 75% dos animais com esse tipo de granuloma com apenas uma lesão e bom estadogeral. O tratamento de longo prazo com itraconazol, nesses gatos com esporotricose refratária, pode manter a infecção controlada e lesões localizadas estáveis de forma temporária, contudo a reativação do fungo pode ocorrer levando a uma resposta imunológica exuberante e ineficiente.

ABSTRACT: Sporotrichosis is a chronic fungal infection caused by Sporothrix species. The occurrence of cases that are resistant to long-term treatment, especially in the nasal planum of cats, emphasizes the importance of studying its pathogenesis. The purpose of this study was to analyze and compare the inflammatory process of cutaneous lesions of feline refractory sporotrichosis to clinical aspects through cytopathological and histopathological examination. Moreover, the study included 13 cats with cutaneous lesions that had been resistant to itraconazole treatment for more than a year. Cutaneous lesions samples were collected for cytopathological, histopathological, and fungal culture analyses. Tissue fragments were processed and stained with hematoxylin-eosin (HE) and Grocott methenamine silver (GMS). Further, two clinical presentations had the highest occurrence: the localized cutaneous form in animals with good general condition and stable disease (n=9, 69.2%) and the disseminated cutaneous form in cats with poor general condition (n=4, 30.8%). In cats with refractory sporotrichosis, the nasal planum (84.6%) was the most common location of lesions. In the cytopathological study, cats with fewer than two lesions and in good general condition (n=9, 69.2%) showed absence or mild yeast intensity (up to 5 yeasts per field), lower intensity of macrophages and neutrophils, and higher intensity of epithelioid cells, lymphocytes, plasma cells, and eosinophils. On the other hand, (n=4, 30.8%) of the cats with disseminated sporotrichosis and a poor general condition had a marked intensity of yeasts, which were mostly phagocytosed by an increased number of macrophages and neutrophils. Of those animals with good general condition, the majority (n=6, 66.7%) had higher eosinophil intensity. In histopathology, malformed suppurative granuloma was the predominant type (n=9, 69.2%) in feline sporotrichosis lesions, followed by well-formed granulomas (n=4, 30.8%). Malformed granulomas showed mild to moderate fungal intensity (55.6%) in animals with good general condition and localized lesions while marked fungal intensity (44.4%) in cats with the disseminated form of the disease and poor general condition. Well-formed granulomas (n=4, 30.7%) had mild to moderate intensity of fungal load, and 75% of the animals with this type of granuloma had only one lesion and were in good general condition. Long-term itraconazole treatment in these cats with refractory sporotrichosis can keep the infection under control and localized lesions stable; however, fungus reactivation can occur, resulting in an exuberant and inefficient immune response.

https://doi.org/10.1590/1678-5150-pvb-6923

Evaluation of Flow Accelerated Corrosion in Typical Recovery Boiler Environments of Energy Production Industries
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Moreira, Rogaciano M.

; Almeida, Tatiana C.

; Bandeira, Merlin C. E.

; Assunção, Felipe R. S.

; Carvalho, Juliana F. A.

; Silva, Elaine F.

; Verbicario, João V. T.

; Mattos, Oscar R.

; Oliveira, Jefferson R.

; Bonfim, André L. C.

; Novgorodecev, André R.

Materials Research

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2022, Volume 25 Suppl. 1 elocation e20210520

Abstract: En | Text: En | PDF: En

Abstract Flow accelerated corrosion (FAC) is a steel degradation that occurs in heat recovery steam generators in the power industry. The mechanism of this corrosion comprises an electrochemical dissolution of the semi-protective magnetite layer (Fe3O4) that is formed within the pipes employed in the boilers. The FAC is influenced by different factors such as fluid velocity, pH and dissolved oxygen concentration. In this context, Rotating Cage tests were used to evaluate the influence of pH and dissolved oxygen content on FAC of A210, P11 and P22 steels. General corrosion was lower for P11 and P22 steels, an effect consistent with the presence of chromium in their compositions. General corrosion was most critical at pH 8.5. The corrosion intensity decreased for the three steels when the dissolved oxygen concentration increased, at 2 m/s. This behavior is coherent considering the most effective precipitation of Fe2O3 inside the pores of the Fe3O4 layer in a more oxidizing environment. For 3 m/s, the corrosion intensity increased for both materials when oxygen increased, showing the shear stress effect. These behaviors were more significant at pH 8.5. About pitting corrosion, the analyzes show localized attack in the majority of coupons, however with very low number of pits.

https://doi.org/10.1590/1980-5373-mr-2021-0520

10.

Substantive rationality of impression management: An analysis of corporate reports of JBS
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Cruz, Juliana C. S.

; Rodrigues, Marly D.

; Araújo, Risolene A. M.

; Silva, Adriana R.

RAM. Revista de Administração Mackenzie

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2022, Volume 23 N. 3 elocation eRAMR220239

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

RESUMO Objetivo: O objetivo deste estudo foi investigar a racionalidade substantiva inerente à prática do gerenciamento de impressões (GI). Originalidade/valor: Com base na taxonomia criada por Merkl-Davies e Brennan (2011), analisam-se: 1. a discussão sob o eixo da perspectiva sociológica; e 2. as ações de racionalidade substantiva do GI que podem se manifestar a partir de ações de gestão simbólica. Nesse sentido, este estudo atende ao chamado de Merkl-Davies et al. (2011) ao colocar em prática um modelo pouco convencional de análise a partir da utilização dos relatórios corporativos (anual e de sustentabilidade) da empresa JBS com especial atenção à Operação “Carne Fraca”. Design/metodologia/abordagem: Foi empreendida uma análise de conteúdo das narrativas contábeis dos relatórios corporativos da JBS entre o período de 2015 a 2018, à luz da estrutura conceitual de Merkl-Davies e Brennan. Resultados: As narrativas contábeis sugerem indícios de GI e da racionalidade substantiva. A racionalidade substantiva foi utilizada pelos preparadores dos relatórios corporativos a fim de legitimar as ações da companhia, sendo as manifestações dessa prática mais significativas no relatório de 2017, ano do evento Operação “Carne Fraca”. As implicações desta pesquisa residem em demonstrar evidências que direcionam as empresas quanto ao uso de narrativas contábeis para convencer a sociedade de suas ações condizentes com a estrutura de regras e normas sociais. Ademais, destacamos que as narrativas contábeis devem ser analisadas com cautela, uma vez que podem ser elaboradas sob a égide do comportamento oportunista do gestor.

ABSTRACT Objective: To investigate the substantive rationality inherent to the practice of impression management (IM). Originality/value: Based on the taxonomy created by Merkl-Davies and Brennan (2011), it is analyzed: 1. the discussion under the sociological perspective; and 2. the actions of substantive rationality in the management of impressions that can manifest through actions of symbolic management. This study responds to the call of Merkl-Davies et al. (2011) by putting into practice an unconventional analytical model based on the use of the corporate reports (annual and sustainability) of the company JBS with special attention to the “Carne Fraca” [Weak Meat] Operation. Design/methodology/approach: A content analysis of the accounting narratives of JBS’ corporate reports between 2015 and 2018 was carried out. Findings: Accounting narratives suggest evidence of IM and substantive rationality. The preparers of the corporate reports used substantive rationality to legitimize the company’s actions, with the most significant manifestations of this practice in the 2017 report, the year of the “Carne Fraca” operation. The implications of this research lie in demonstrating evidence that guides companies regarding the use of accounting narratives to convince society of their actions as consistent with the structure of social rules and norms. Furthermore, we emphasize that the accounting narratives must be analyzed with caution since they can be elaborated under the influence of the manager’s opportunistic behavior.

https://doi.org/10.1590/1678-6971/eramr220239.en

11.

Seroconversion in asymptomatic COVID-19 pediatric patients with rheumatic diseases of one tertiary referral hospital
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Simon, Juliana R.

; Pereira, Maria F.B.

; Marques, Heloisa H.

; Elias, Adriana M.

; Sakita, Neusa K.

; Ferreira, Juliana C.O.A.

; Precioso, Alexander Roberto

; Grisi, Sandra J.F.E.

; Ferrer, Ana Paula S.

; Bain, Vera

; Silva, Clovis A.

; Campos, Lúcia M.A.

Clinics

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2022, Volume 77 elocation 100110

Abstract: En | Text: En | PDF: En

Abstract Objectives: To evaluate seroconverted asymptomatic COVID-19 in pediatric Autoimmune Rheumatic Diseases (ARDs) patients and to identify the risk factors related to contagion. Methods: A cross-sectional study was conducted in March 2021, before vaccination of children and adolescents in Brazil, including 77 pediatric ARDs patients, followed at a tertiary hospital and 45 healthy controls, all of them without a previous diagnosis of COVID-19. Data was obtained by a questionnaire with demographic data, symptoms compatible with COVID-19 over the previous year, and contact with people with confirmed COVID-19. Patient’s medical records were reviewed to access data regarding disease and current medications. A qualitative immunochromatographic SARS-CoV-2 test was performed on all participants. Results: Patients and controls were similar in terms of female gender (70.1% vs. 57.8%, p = 0.173), age (14 vs. 13 years, p = 0.269) and SARS-CoV-2 positive serology (22% vs. 15.5%, p = 0.481). 80.5% of rheumatic patients were in use of immunosuppressive drugs: 27.3% of them used corticosteroids (33.3% in high doses), and 7.8% on immunobiologicals. No statistical differences were found between positive (n = 17) and negative serology (n = 60) patients regarding demographic/socioeconomic data, contact with people with confirmed COVID-19, use and number of immunosuppressive drugs, use and dose of corticosteroids, use of hydroxychloroquine and immunobiological drugs (p > 0.05). Conclusions: Pediatric rheumatic disease patients were infected at the same rate as healthy ones. Neither the underlying pathology nor its immunosuppressive treatment seemed to interfere with contagion risk.

https://doi.org/10.1016/j.clinsp.2022.100110

12.

Peripheral isolation and demographic stability are reflected in the genetic diversity of the populations of the Helmeted Manakin: a bird endemic to the gallery forests
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SOUZA, THAINARA O.

; LUNA, LEILTON W.

; ARARIPE, JULIANA

; SILVA, WEBER A. DE G. E

; REGO, PÉRICLES S. DO

Anais da Academia Brasileira de Ciências

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2022, Volume 94 Suppl. 4 elocation e20201206

Abstract: En | Text: En | PDF: En

Abstract The Cerrado encompasses a complex network of hydrographic basins, which is responsible for the formation and maintenance of the riparian and gallery forests. Alterations in the vegetation resulting from the paleoclimatic changes that occurred during the Pleistocene influenced the current distribution of these humid forests. To understand of the evolutionary dynamics of this landscape on the population structure of the associated organisms, we studied the population genetics of the Antilophia galeata (Pipridae), a bird endemic to the gallery forests of the Cerrado. For this, we evaluated the variability of the mitochondrial control region of 71 A. galeata specimens from 18 localities distributed throughout the Cerrado. The results indicated the existence of significant substructure among the populations located in the peripheral areas of the Cerrado, in comparison with the populations found in the central portion, reflecting historical changes in the environment. We also found high levels of diversity in all the populations, while the analysis of the demographic history revealed a scenario of stability. Overall, then, these findings indicate that the historical modifications of the gallery forest distribution may have been most accentuated in the peripheral zones, with a greater stability and connectivity persisting in the central portion of the biome.

https://doi.org/10.1590/0001-3765202220201206

13.

REDUçãO DE CO2 EM HIDROCARBONETOS E OXIGENADOS: FUNDAMENTOS, ESTRATéGIAS E DESAFIOS
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Silva, Gelson T. S. T. da

; Lopes, Osmando F.

; Dias, Eduardo H.

; Torres, Juliana A.

; Nogueira, André E.

; Faustino, Leandro A.

; Prado, Fernando S.

; Patrocínio, Antônio O. T.

; Ribeiro, Caue

Química Nova

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aug 2021, Volume 44 N. 8 Pages 963 - 981

Abstract: Pt | Text: Pt | PDF: Pt

CO2 REDUCTION TO HYDROCARBONS AND OXYGENATES: FUNDAMENTALS, STRATEGIES AND CHALLENGES. The development of renewable energy sources (e.g., solar and wind) moves foward, the tendance for replacing fossil fuels increases. However, these technologies have as primary barriers to industrial processes’ efficiency and especially storage. Thus, CO2 reduction routes using these energy sources could chemically store part of the energy as fuels or chemicals, offering alternatives to current oil and gas industry. This process is inspired by photosynthesis, e.g., photochemical or electrochemical processes, using homogeneous or heterogeneous catalysts. Nevertheless, this reaction is thermodynamically unfavorable and has very slow kinetics, given the high stability of the CO2 molecule and the complexity of the redox reactions involved. Therefore, this review addresses this process’s kinetic and thermodynamic challenges, and the fundamental concepts of the photo(electro)chemical processes for CO2 reduction, besides presenting and discussing the materials with the potential to act as catalysts. The main reaction mechanisms and advances in the understanding of such processes are discussed, as well as future perspectives

https://doi.org/10.21577/0100-4042.20170745 107 downloads

14.

Synthesis, in silico Study and Antileishmanial Evaluation of New Selenides Derived from 7-Chloro-quinoline and N-Phenylacetamides
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Huang, Min-Fu N.

; Luis, José A. S.

; Silva, Alison P. da

; Rocha, Juliana C.

; Lima, Tatjana K. S.

; Scotti, Marcus T.

; Scotti, Luciana

; Oliveira, Rafael F. de

; Souza, Helivaldo D. S.

; Athayde-Filho, Petrônio F. de

; Barbosa-Filho, José M.

Journal of the Brazilian Chemical Society

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apr 2021, Volume 32 N. 4 Pages 712 - 721

Abstract: En | Text: En | PDF: En

This study describes a virtual screening performed for two series of selenides (28 compounds), derived from N-phenylacetamides chlorides and 7-chloro-quinoline, to determine their potential for leishmanicidal activity against Leishmania amazonensis and Leishmania donovani. Seven compounds were predicted as potential leishmanicides; therefore, they were synthesized from elemental selenium, as a precursor for the production of NaHSe, and subsequent reactions with 4,7-dichloro-quinoline and N-phenylacetamides chlorides were performed. The compounds were characterized by infrared (IR), 1H and 13C nuclear magnetic resonance (NMR), and sent for in vitro cytotoxicity tests against L. amazonensis and were found to be active and selective, and two compounds presented half-maximal inhibitory concentrations (IC50) of 5.67 and 10.81 µg mL-1. They also presented good interaction energies in the docking study, suggesting that may exert their effects by inhibiting the N-myristoyltransferase and O-acetylserine sulfhydrylase enzymes in parasites.

https://doi.org/10.21577/0103-5053.20200223 183 downloads

15.

CURCUMINA COMO INDICADOR NATURAL DE PH: UMA ABORDAGEM TEÓRICA-EXPERIMENTAL PARA O ENSINO DE QUÍMICA
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Oliveira, Drielly E. T. B. de

; Bezerra, Leonardo A. B.

; Oliveira, Romário J.

; Moraes, Vitocley B. de

; Silva, Juliana Angeiras Batista da

; Freitas Filho, João R. de

; Freitas, Juliano C. Rufino

; Ramos, Clécio S.

Química Nova

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feb 2021, Volume 44 N. 2 Pages 217 - 223

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

This paper proposes the development of a simple experiment with easily accessible and low cost materials, enabling its practice with or without laboratory infrastructure, with feasibility for computational theoretical study. On the other hand, the objective of the work is to develop a chemical experiment that demonstrates that the chromophore curcumin (natural indicator) is responsible for indicating the acidity or basicity of a given solution. The experiment has different applicability, being useful in the approach of different chemical contents, showing potential for multi and interdisciplinary approaches. Subjects such as tautomeric equilibrium, chromophoric compounds, hydrogen potential, UV-Vis electron absorption spectra analysis and molecular modeling are explored.

https://doi.org/10.21577/0100-4042.20170625 287 downloads

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