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Arthropod-borne viruses (arboviruses) are a severe public health problem worldwide, consisting of a significant part of all the emerging infectious diseases. It is estimated that arboviruses infect hundreds of millions of people globally each year, resulting in several thousand deaths. Despite their clear health threat, there are no prophylactic or pharmacological therapies available for most of them. Control of arbovirus infections is beyond pharmacological options; handling the larvae of mosquitos is an important and successful strategy, although currently available insecticides and larvicides are already associated with resistance. Therefore, searching for new strategies to prevent arbovirus infection is urgent and necessary. Marine organisms are an excellent source for structurally novel compounds due to their unique secondary metabolism, with outstanding antiviral and larvicidal activities. In the present review, we explored the ability of various marine natural products (MNPs) such as indole derivatives, diketopiperazines, scequinadoline A, cyclohexadepsipeptides, and others, to act as both antiviral and larvicidal, in an attempt to highlight their structure activity potential against the most relevant arboviruses affecting the human health. Arthropodborne Arthropod borne (arboviruses worldwide diseases year deaths threat them options strategy resistance Therefore necessary metabolism activities review MNPs (MNPs derivatives diketopiperazines A cyclohexadepsipeptides others

https://doi.org/10.21577/0103-5053.20230012

Production of mycelial biomass, proteases and protease inhibitors by Ganoderma lucidum under different submerged fermentation conditions
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Pessoa, V. A.

; Soares, L. B. N.

; Silva, G. L.

; Vasconcelos, A. S.

; Silva, J. F.

; Fariña, J. I.

; Oliveira-Junior, S. D.

; Sales-Campos, C.

; Chevreuil, L. R.

Brazilian Journal of Biology

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2023, Volumen 83 elocation e270316

Resumen: En Pt | Texto: En Pt | PDF: En | PDF: Pt

Abstract Ganoderma lucidum is a medicinal mushroom widely recognized as a source of biomolecules with pharmacological properties, however, little is known about the factors that influence the synthesis of bioactive proteins by this fungus when cultivated under submerged fermentation. The objective of this work was to evaluate the production of mycelial biomass and intracellular proteases and protease inhibitors by G. lucidum cultivated under different submerged fermentation conditions. The cultivation was carried out in a medium composed of glucose (10 or 20 g.L-1), soy peptone (2.5 or 5 g.L-1) and yeast extract (5 g.L-1), with incubation under agitation (120 rpm) and non-agitation, totaling 8 experimental conditions. Biomass production was determined from the dry weight, while glucose consumption was estimated by quantification of reducing sugars. The proteins were extracted in NaCl (0.15 M), and the protein extracts were submitted to protein quantification by the Bradford method, total proteolytic activity using azocasein, caseinolytic and fibrinolytic activity in Petri dishes, activity of serine (trypsin and chymotrypsin) and cysteine (papain) protease inhibitors. Cultivation in agitated condition showed higher biomass production with a maximum value of 7 g.L-1, in addition to higher activities of trypsin, chymotrypsin and papain inhibitors, with 154 IU.mg-1, 153 IU.mg-1 e 343 IU.mg-1 of protein, respectively. The non-agitated condition showed a greater potential for obtaining proteins, total proteases, caseinolytic and fibrinolytic enzymes, with maximum values of 433 mg.g-1 of extract, 71 U.mL-1 of extract, 63.62 mm2 and 50.27 mm2, respectively. Thus, a medium composed of soy peptone, yest extract and glucose in a 1:2:4 proportion is recommended, under agitation to produce protease inhibitors, and the non-agitated condition when the target is, mainly caseinolytic and fibrinolytic enzymes.

Resumo Ganoderma lucidum é um cogumelo medicinal amplamente reconhecido como fonte de biomoléculas com propriedades farmacológicas, entretanto, pouco se conhece acerca dos fatores que influenciam a síntese de proteínas bioativas por esse fungo, quando cultivado sob fermentação submersa. O objetivo deste trabalho foi avaliar a produção de biomassa micelial e de proteases e inibidores de proteases intracelulares por G. lucidum cultivado em diferentes condições de fermentação submersa. O cultivo foi realizado em meio contendo glicose (10 ou 20 g.L-1), peptona de soja (2,5 ou 5 g.L-1) e extrato de levedura (5 g.L-1), com incubação sob agitação (120 rpm) ou não-agitado, totalizando 8 condições experimentais. A produção de biomassa foi determinada a partir do peso seco e o consumo de glicose a partir da quantificação de açúcares redutores. As proteínas foram extraídas em NaCl (0,15 M) e os extratos proteicos foram submetidos à quantificação de proteínas pelo método de Bradford, atividade proteolítica total usando azocaseína, atividade caseinolítica e fibrinolítica em placa de Petri, atividade de inibidores de serino-proteases (tripsina e quimotripsina) e cisteíno-protease (papaína). O cultivo em condição agitada apresentou maior produção de biomassa com valor máximo de 7g.L-1, além de maiores atividades de inibidores de tripsina, quimotripsina e papaína, com 154 UI.mg-1, 153 UI.mg-1 e 343 UI.mg-1 de proteína, respectivamente. A condição não-agitada demonstrou maior potencial para a obtenção de proteínas, proteases totais, enzimas caseinolíticas e fibrinolíticas, com valores máximos de 433 mg.g-1 de extrato, 71 U.mL-1 de extrato, 63,62 mm2 e 50,27 mm2, respectivamente. Assim, recomenda-se o meio composto de peptona de soja, extrato de levedura e glicose na proporção 1:2:4, em condição agitada para a produção de inibidores de proteases, e a condição não-agitada para a síntese de proteases, principalmente enzimas caseinolíticas e fibrinolíticas.

https://doi.org/10.1590/1519-6984.270316

Multidisciplinary Scientific Cruises for Environmental Characterization in the Santos Basin – Methods and Sampling Design
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Moreira, Daniel L.

; Dalto, Adriana G.

; Figueiredo JR, Alberto G.

; Valerio, Aline M.

; Detoni, Amalia M. S.

; Bonecker, Ana C. T.

; Signori, Camila N.

; Namiki, Cláudia

; Sasaki, Dalton K.

; Pupo, Daniel V.

; Silva, Danilo A.

; Kutner, Deborah S.

; Duque-Castaño, Diana C.

; Marcon, Eduardo H.

; Gallotta, Fabiana D. C.

; Paula, Fabiana S.

; Gallucci, Fabiane

; Roque, Gabriela C. F.

; Campos, Giulia S.

; Fonseca, Gustavo

; Mattos, Gustavo

; Lavrado, Helena P.

; Silveira, Ilson C. A. da

; Costa, Jessica O.

; Santos Filho, João R. dos

; Carneiro, Juliane C.

; Moreira, Julio C.F.

; Rozo, Laura

; Araujo, Leandro F.M.

; Lazzari, Letícia

; Silva, Letícia O. da

; Michelazzo, Luan S.

; Fernandes, Luciano F.

; Dottori, Marcelo

; Araújo Jr., Marcus A. G. de

; Chuqui, Mateus G.

; Ceccopieri, Milena

; Borges-Silva, Milton

; Kampel, Milton

; Bergo, Natascha M.

; Silva, Paulo V. M.

; Tura, Pedro M.

; Moura, Rafael B. de

; Romano, Renato G.

; Martins, Renato P.

; Carreira, Renato S.

; Toledo, Rodrigo G.A.

; Bonecker, Sérgio L.C.

; Disaró, Sibelle T.

; Rodrigues, Silvana V.

; Corbisier, Thais N.

; Vicente, Thaisa M.

; Paiva, Vitor G. de

; Pellizari, Vivian H.

; Belo, Wellington C.

; Brandini, Frederico P.

; Sousa, Silvia H.M

Ocean and Coastal Research

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2023, Volumen 71 Supl. 3 elocation e23022

Resumen: En | Texto: En | PDF: En

Abstract The Santos Basin (SB) is the main petroliferous basin in the Brazilian continental margin and one of the most studied marine areas in Brazil. However, historical data suggest that new efforts should be carried out to acquire quantitative biological data, especially in the deep sea, to establish the baseline of essential ocean variables in different ecosystems for future monitoring programs. The Brazilian energy company Petrobras planned and executed 24 oceanographic cruises over a period of 2 years to assess the benthic (SANSED cruise) and pelagic (SANAGU cruise) systems of the SB (356 days at sea in 2019 and 2021/2022). These efforts were part of the Santos Project, which comprised a comprehensive environmental study aimed at investigating benthic and pelagic variables to characterize ecology, biogeochemistry, thermohaline properties of water masses, and ocean circulation patterns, geomorphology, and sedimentology, as well as organic and inorganic chemistry. Here we present the detailed sampling designs and the field methods employed on board, during the SB scientific cruises. All sampling protocols were based on standardized approaches. For the benthos analyses, triplicate sediment samples were performed using a GOMEX-type box corer (0.25 m²) or a large modified Van Veen grab (0.75 m²) at 100 stations ranging from 25 to 2400 m depth. At each station, 25 geochemical and physico-chemical parameters were analyzed in addition to micro-, meio-, and macrofauna and living foraminifera samples. For the pelagic system, 60 stations were selected to investigate the plankton community, ranging in size from pico- to macroplankton, through vertical, horizontal, and oblique net hauls (20, 200, and 500 μm mesh size), as well as 25 biogeochemical parameters collected with an aid of a CTD-rosette sampler. Part of this scientific information also serves the Regional Environmental Characterization Project (PCR-BS) in support of Petrobras’ Santos Basin drilling licensing process led by the Brazilian Environmental Agency – IBAMA. This project contributes to the sustainable development of the SB, in line with the guidelines of the United Nations Decade of Ocean Science for Sustainable Development.

https://doi.org/10.1590/2675-2824071.22072dlm

Radiation Efficiency of an Electrically Small Dual-band UHF Microstrip Patch Antenna Using Wheeler Cap Method
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da Silva, W. G.

; Campos, A. L. P. S.

; Guerra, J. R. F.

; da Silva, I. B. T.

Journal of Microwaves, Optoelectronics and Electromagnetic Applications

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Mar 2022, Volumen 21 Nº 1 Paginas 1 - 10

Resumen: En | Texto: En | PDF: En

Abstract Determining the radiation efficiency of an antenna is a difficult task that becomes challenging when it is about electrically small antennas. This work investigates the applicability of the Wheeler cap method to measure the radiation efficiency of a UHF dual-band compact microstrip patch antenna. An overview of Wheeler method is presented. An adaptation to the original method is suggested to measure the efficiency of a small slitted microstrip patch antenna operating at two frequencies (400 MHz and 431 MHz). A third-order equivalent RLC circuit has been proposed. The measurements were performed using three metal shields of different sizes and shapes. Measured results agreed with the theoretical model. However, the metallic shield significantly interferes in the fringing fields, reducing the accuracy of the method. Despite the inaccuracy observed in the measurements, the method proved to be attractive due to its low cost and ease of measurement. The contribution of this work is to apply the method to an antenna under test with a high degree of miniaturization, low efficiency, and very narrow band, in addition to using a thick substrate. No previous work with this focus has been found in the literature, up to date.

https://doi.org/10.1590/2179-10742022v21i1253618

Analysis of the Influence of Contaminants on Microhardness Sintered Boron Carbide Samples
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Aguilera, L. S.

; Costa Filho, M. A. F.

; Costa Neto, C. A.

; Campos, J. B. de

Journal of applied research and technology

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2022, Volumen 20 Nº 4 Paginas 448 - 459

Resumen: En | Texto: En | PDF: En

Abstract: This work presents ANOVA and Tukey’s statistic tests that were conducted in Knoop microhardness results of boron carbide sintered samples. Three samples, A, B, and C, of different processing conditions were tested and statistical analysis showed that microhardness results are strongly influenced by porosity and chemical composition, mainly due to the presence of C(2H) and WB2.5 contaminant phases. Those phases promoted higher densification in A and B samples and it was found that A ≈ B > C is the relation between the microhardness results of the samples, while A ≈ B < C is the porosity ratio of the samples. Furthermore, this work aims to apply a statistical tool to evaluate the microhardness results performed on advanced ceramics and, using these results, to control parameters in the sintering process, showing that a deeper statistical analysis is necessary for the interpretation and validation of the results merit.

https://doi.org/10.22201/icat.24486736e.2022.20.4.1327

Intra and inter-monkey transmission of bacteria in wild black capuchins monkeys (Sapajus nigritus): a preliminary study
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Grassotti, T. T.

; Zvoboda, D. A.

; Costa, L. F. X.

; Christiano, F. D. P.

; Mann, M. B.

; Wagner, P. G. C.

; Campos, A. A. S.

; Frazzon, J.

; Frazzon, A. P. G.

Brazilian Journal of Biology

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2022, Volumen 82 elocation e237460

Resumen: En | Texto: En | PDF: En

https://doi.org/10.1590/1519-6984.237460 129 descargas

Poor Sleep quality and health-related quality of life impact in adolescents with and without chronic immunosuppressive conditions during COVID-19 quarantine
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Helito, Alberto C.

; Lindoso, Livia

; Sieczkowska, Sofia M.

; Astley, Camilla

; Queiroz, Ligia B.

; Rose, Natalia

; Santos, Claudia Renata P.

; Bolzan, Thalis

; Peralta, Rita María I.A.

; Franco, Ruth R.

; Cominato, Louise

; Pereira, Rosa Maria R.

; Tannuri, Uenis

; Campos, Lucia Maria A.

; Lourenço, Benito

; Toma, Ricardo K.

; Medeiros, Karina

; Watanabe, Andréia

; Grangeiro, Patricia Moreno

; Farhat, Sylvia C.

; Casella, Caio B.

; Polanczyk, Guilherme V.

; Gualano, Bruno

; Silva, Clovis A.

; Sallum, Adriana M. E.

; Iraha, Amanda Y.

; Ihara, Bianca P.

; Mazzolani, Bruna C.

; Martinez, Claudia A.

; Strabelli, Claudia A. A.

; Fonseca, Claudia B.

; Lima, Dandara C. C.

; Setoue, Debora N. D.

; Roz, Deborah F. P.

; Smaira, Fabiana I.

; Roschel, Hamilton

; Miyatani, Helena T.

; Marques, Isabela G.

; Oba, Jane

; Ferreira, Juliana C. O.

; Simon, Juliana R.

; Kozu, Katia

; Saccani, Ligia P.

; Martiniano, Lorena V. M.

; Miranda, Luana C. A.

; Silva, Luiz E. V.

; Laurentino, Moisés F.

; Aikawa, Nadia E.

; Sakita, Neusa K.

; Tanigava, Nicolas Y.

; Pereira, Paulo R. A.

; Palmeira, Patrícia

; Angelo, Simone S.

; Lavorato, Sofia S. M.

; Bernardes, Tamires M.

; Franco, Tathiane C.

; Viana, Vivianne S. L.

; Barros, Vera P. M. F. R.

; Zheng, Yingying

Clinics

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2021, Volumen 76 elocation e3501

Resumen: En | Texto: En | PDF: En

OBJECTIVE: To assess the possible factors that influence sleep quality in adolescents with and without chronic immunosuppressive conditions quarantined during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: This cross-sectional study included 305 adolescents with chronic immunocompromised conditions and 82 healthy adolescents. Online surveys were completed, which included questions on socio-demographic data and self-rated healthcare routine during COVID-19 quarantine and the following validated questionnaires: the Pittsburgh Sleep Quality Index (PSQI), Pediatric Quality of Life Inventory 4.0 (PedsQL4.0), and Pediatric Outcome Data Collection Instrument (PODCI). RESULTS: The median current age [14 (10-18) vs. 15 (10-18) years, p=0.847] and frequency of female sex (62% vs. 58%, p=0.571) were similar in adolescents with chronic conditions compared with healthy adolescents. The frequency of poor sleep quality was similar in both groups (38% vs. 48%, p=0.118). Logistic regression analysis, including both healthy adolescents and adolescents with chronic conditions (n=387), demonstrated that self-reported increase in screen time (odds ratio [OR] 3.0; 95% confidence interval [CI] 1.3-6.8; p=0.008) and intrafamilial violence report (OR 2.1; 95% CI 1.2-3.5; p=0.008) were independently associated with poor sleep quality in these adolescents. However, the PODCI global function score was associated with a lower OR for poor sleep quality (OR 0.97; 95% CI 0.94-0.99; p=0.001). Further logistic regression, including only adolescents with chronic conditions (n=305), demonstrated that self-reported increase in screen time (OR 3.1; 95% CI 1.4-6.8; p=0.006) and intrafamilial violence report (OR 2.0; 95% CI 1.2-3.4; p=0.011) remained independently associated with poor quality of sleep, whereas a lower PODCI global function score was associated with a lower OR for sleep quality (OR 0.96; 95% CI 0.94-0.98; p<0.001). CONCLUSION: Self-reported increases in screen time and intrafamilial violence report impacted sleep quality in both healthy adolescents and those with chronic conditions. Decreased health-related quality of life was observed in adolescents with poor sleep quality.

https://doi.org/10.6061/clinics/2021/e3501

Persistent symptoms and decreased health-related quality of life after symptomatic pediatric COVID-19: A prospective study in a Latin American tertiary hospital
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Fink, Thais T.

; Marques, Heloisa H.S.

; Gualano, Bruno

; Lindoso, Livia

; Bain, Vera

; Astley, Camilla

; Martins, Fernanda

; Matheus, Denise

; Matsuo, Olivia M.

; Suguita, Priscila

; Trindade, Vitor

; Paula, Camila S.Y.

; Farhat, Sylvia C.L.

; Palmeira, Patricia

; Leal, Gabriela N.

; Suzuki, Lisa

; Odone Filho, Vicente

; Carneiro-Sampaio, Magda

; Duarte, Alberto José S.

; Antonangelo, Leila

; Batisttella, Linamara R.

; Polanczyk, Guilherme V.

; Pereira, Rosa Maria R.

; Carvalho, Carlos Roberto R.

; Buchpiguel, Carlos A.

; Latronico, Ana Claudia

; Seelaender, Marilia

; Silva, Clovis Artur

; Pereira, Maria Fernanda B.

; Sallum, Adriana M. E.

; Brentani, Alexandra V. M.

; Neto, Álvaro José S.

; Ihara, Amanda

; Santos, Andrea R.

; Canton, Ana Pinheiro M.

; Watanabe, Andreia

; Santos, Angélica C. dos

; Pastorino, Antonio C.

; Franco, Bernadette D. G. M.

; Caruzo, Bruna

; Ceneviva, Carina

; Martins, Carolina C. M. F.

; Prado, Danilo

; Abellan, Deipara M.

; Benatti, Fabiana B.

; Smaria, Fabiana

; Gonçalves, Fernanda T.

; Penteado, Fernando D.

; Castro, Gabriela S. F. de

; Gonçalves, Guilherme S.

; Roschel, Hamilton

; Disi, Ilana R.

; Marques, Isabela G.

; Castro, Inar A.

; Buscatti, Izabel M.

; Faiad, Jaline Z.

; Fiamoncini, Jarlei

; Rodrigues, Joaquim C.

; Carneiro, Jorge D. A.

; Paz, Jose A.

; Ferreira, Juliana C.

; Ferreira, Juliana C. O.

; Silva, Katia R.

; Bastos, Karina L. M.

; Kozu, Katia

; Cristofani, Lilian M.

; Souza, Lucas V. B.

; Campos, Lucia M. A.

; Silva Filho, Luiz Vicente R. F.

; Sapienza, Marcelo T.

; Lima, Marcos S.

; Garanito, Marlene P.

; Santos, Márcia F. A.

; Dorna, Mayra B.

; Aikawa, Nadia E.

; Litvinov, Nadia

; Sakita, Neusa K.

; Gaiolla, Paula V. V.

; Pasqualucci, Paula

; Toma, Ricardo K.

; Correa-Silva, Simone

; Sieczkowska, Sofia M.

; Imamura, Marta

; Forsait, Silvana

; Santos, Vera A.

; Zheng, Yingying

Clinics

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2021, Volumen 76 elocation e3511

Resumen: En | Texto: En | PDF: En

OBJECTIVES: To prospectively evaluate demographic, anthropometric and health-related quality of life (HRQoL) in pediatric patients with laboratory-confirmed coronavirus disease 2019 (COVID-19) METHODS: This was a longitudinal observational study of surviving pediatric post-COVID-19 patients (n=53) and pediatric subjects without laboratory-confirmed COVID-19 included as controls (n=52) was performed. RESULTS: The median duration between COVID-19 diagnosis (n=53) and follow-up was 4.4 months (0.8-10.7). Twenty-three of 53 (43%) patients reported at least one persistent symptom at the longitudinal follow-up visit and 12/53 (23%) had long COVID-19, with at least one symptom lasting for >12 weeks. The most frequently reported symptoms at the longitudinal follow-up visit were headache (19%), severe recurrent headache (9%), tiredness (9%), dyspnea (8%), and concentration difficulty (4%). At the longitudinal follow-up visit, the frequencies of anemia (11% versus 0%, p=0.030), lymphopenia (42% versus 18%, p=0.020), C-reactive protein level of >30 mg/L (35% versus 0%, p=0.0001), and D-dimer level of >1000 ng/mL (43% versus 6%, p=0.0004) significantly reduced compared with baseline values. Chest X-ray abnormalities (11% versus 2%, p=0.178) and cardiac alterations on echocardiogram (33% versus 22%, p=0.462) were similar at both visits. Comparison of characteristic data between patients with COVID-19 at the longitudinal follow-up visit and controls showed similar age (p=0.962), proportion of male sex (p=0.907), ethnicity (p=0.566), family minimum monthly wage (p=0.664), body mass index (p=0.601), and pediatric pre-existing chronic conditions (p=1.000). The Pediatric Quality of Live Inventory 4.0 scores, median physical score (69 [0-100] versus 81 [34-100], p=0.012), and school score (60 [15-100] versus 70 [15-95], p=0.028) were significantly lower in pediatric patients with COVID-19 at the longitudinal follow-up visit than in controls. CONCLUSIONS: Pediatric patients with COVID-19 showed a longitudinal impact on HRQoL parameters, particularly in physical/school domains, reinforcing the need for a prospective multidisciplinary approach for these patients. These data highlight the importance of closer monitoring of children and adolescents by the clinical team after COVID-19.

https://doi.org/10.6061/clinics/2021/e3511

Preparation of low-cost ceramic membranes for microfiltration using sugarcane bagasse ash as a pore-forming agent
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Andrade, R. M.

; Jaques, N. G.

; Sousa, J.

; Dutra, R. P. S.

; Macedo, D. A.

; Campos, L. F. A.

Cerâmica

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Dic 2019, Volumen 65 Nº 376 Paginas 620 - 625

Resumen: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo Membranas cerâmicas são de grande interesse industrial em processos de separação. Elas são caracterizadas por elevada estabilidade química/térmica e capacidade de filtração em temperaturas acima de 500 °C em uma larga faixa de valores de pH. Entretanto, a grande desvantagem das membranas cerâmicas é o elevado custo de produção envolvendo matérias-primas sintéticas, geralmente alumina e zircônia. Nesse contexto, membranas cerâmicas de baixo custo foram preparadas por sinterização reativa usando uma mistura de argila caulinítica e cinza de bagaço de cana de açúcar. Análises de distribuição de tamanho de partícula, térmica, mineralógica e de composição química foram realizadas para estudar as matérias-primas. As propriedades tecnológicas e de permeabilidade à água foram determinadas em amostras queimadas entre 800 e 1000 °C. A eficiência de filtração foi medida através de análises comparativas entre a água bruta e o filtrado. O tamanho médio dos poros entre 2,5 e 6,0 µm viabiliza o uso das membranas derivadas de cinza de bagaço de cana de açúcar em processos de microfiltração.

Abstract Ceramic membranes are of great industrial interest in separation processes. They are characterized by high chemical and thermal stabilities and filtration capacity at high temperatures (>500 °C) in a wide range of pH values. However, the major disadvantage of ceramic membranes is the high-cost of production involving synthetic raw materials, usually alumina and zirconia. In this work, low-cost ceramic membranes were prepared by solid-state reactive firing using a mixture of kaolinite clay and sugarcane bagasse ash. Particle size distribution, thermal, mineralogical, and chemical composition analyses were carried out to study the raw materials. Technological properties and water permeability were investigated in samples fired between 800 and 1000 °C. The filtration efficiency was measured by comparative analyses between the raw water and the filtrate. The mean pore size ranging from 2.5 to 6.0 μm makes the sugarcane bagasse ash derived ceramic membranes suitable for microfiltration processes.

https://doi.org/10.1590/0366-69132019653762696 871 descargas

10.

Synthesis and Biological Evaluation of New Eugenol-Derived 1,2,3- Triazoles as Antimyco bacterial Agents
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Santos, Thiago dos

; Coelho, Camila M.

; Elias, Thiago C.

; Siqueira, Fallon S.

; Nora, Eloísa S. S. D.

; Campos, Marli M. A. de

; Souza, Gabriel A. P. de

; Coelho, Luiz F. L.

; Carvalho, Diogo T.

Journal of the Brazilian Chemical Society

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Jul 2019, Volumen 30 Nº 7 Paginas 1425 - 1436

Resumen: En | Texto: En | PDF: En

Eugenol has diverse biological properties including antimycobacterial activity, and the triazole ring is an important heterocycle in antimycobacterial compounds. Therefore, this research aimed to synthesize novel eugenol-derived 1,2,3-triazole as antimycobacterial agents with interesting cytotoxic profile and pharmacological assets. Sixteen compounds were obtained and characterized by nuclear magnetic resonance (NMR), infrared (IR), and high-resolution mass spectrometry (HRMS). Among them, the best growth inhibition properties from a microdilution assay were observed for three derivatives: a benzylic ether (minimum inhibitory concentration (MIC) = 48.89 µM) against Mycobacterium abscessus (ATCC 19977), an O-galactosyde (MIC = 31.76 µM) against Mycobacterium massiliense (ATCC 48898) and a sulfonate (MIC = 88.64 µM) against Mycobacterium fortuitum (ATCC 6841). They can form biofilms, and the infection progression is challenging to control due to multi-drug resistance profiles against diverse antibiotics. In conclusion, the above-mentioned compounds represent starting points in the search of bioactive molecules against mycobacteria with low cytotoxicity and better pharmacological profiles.

https://doi.org/10.21577/0103-5053.20190038 484 descargas

11.

Foraging behavior and at-sea distribution of White-Tailed Tropicbirds in tropical ocean
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Campos, L. F. A. S.

; Andrade, A. B.

; Bertrand, S.

; Efe, M. A.

Brazilian Journal of Biology

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Dic 2018, Volumen 78 Nº 3 Paginas 556 - 563

Resumen: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo Utilizamos aparelhos de GPS miniaturizados e observações de campo para determinar padrões de forrageio e comportamento em ninho da espécie ameaçada Rabos-de-palha-de-bico-laranja Phaethon lepturus em sua colônia reprodutiva do Atlântico Sul. Padrão dual de forrageio foi observado, com alternância entre viagens longas e curtas. Aves responsáveis por cuidado parental efetuaram viagens curtas de forrageio com em média 25 ± 17 km de distância da colônia, distância total percorrida média de 79 ± 65 km e duração média de 4.02 ± 5.28 horas. As aves saíram da colônia entre o amanhecer e o entardecer, enquanto seus parceiros estavam em alto-mar em viagens longas de quatro a 11 dias de duração, com média de distância máxima da colônia de 105 ± 47.48 km. Filhotes foram constantemente deixados sozinhos por várias horas, e predação por Johngartia lagostroma, consumo de ovos por Goniopsis cruentata e competição intra-específica possivelmente foram responsáveis por sua morte.

Abstract We used miniaturized GPS loggers and site observations to access foraging patterns and nest behaviour of the White-tailed Tropicbird Phaethon lepturus (WTTB), an endangered species at its South Atlantic breeding colony. Dual foraging pattern was observed with alternation between long and short foraging trips. Birds responsible for nest attendance engaged in short foraging trips with mean distance from colony of 25 ± 17 km, total distance covered of 79 ± 65 km and mean duration of 4.02 ± 5.28 hours. Birds flew by dawn and returned before dusk while partners were at sea for long foraging trips that ranged from four to 11 days, with mean maximum distance from colony of 105 ± 47.48 km. Chicks were usually left alone for hours and chick predation by Land Crab Johngartia lagostroma, egg consumption by Goniopsis cruentata and intra-specific competition are suspected to be responsible for high chick mortality rates.

https://doi.org/10.1590/1519-6984.173578 1228 descargas

12.

ANALYSIS OF A BRAZILIAN THERMAL PLANT OPERATION APPLYING ENERGETIC AND EXERGETIC BALANCES
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Fraga, M. M. C.

; Campos, B. L. de O.

; Lisboa, M. S.

; Almeida, T. B. de

; Costa, A. O. S. da

; Lins, V. de F. C.

Brazilian Journal of Chemical Engineering

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Dic 2018, Volumen 35 Nº 4 Paginas 1395 - 1403

Resumen: En | Texto: En | PDF: En

ABSTRACT When the level of water reservoirs from Brazilian hydroelectric stations is low, additional thermal plants are turned on to complement the power of the national electric system. The fuels used in these plants are generally natural gas, fuel oil and coal. The objective of this work is to analyze energetically and exergetically a fuel oil thermal plant in operation in Brazil. Real industrial data were used in this analysis. The calculated total work of the turbine is 120.73 MW, which is close to the real value of 120 MW. The cycle energetic efficiency is 36.8% and the exergetic efficiency is 34.4%. The highest exergy destruction was found to be in the boiler (177.11 MW), followed by the high pressure turbine (13.37 MW), due to larger irreversibilities in the processes of these equipment. The exergetic analysis functioned as a complement to the energetic analysis, pointing out where the greatest irreversibilities and improvement potential are: in the boiler.

https://doi.org/10.1590/0104-6632.20180354s20170425 1273 descargas

13.

Estudo da incorporação de pó de concha de marisco em massa de porcelanato
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Fulgêncio, E. B. G. A.

; Medeiros, F. K. de

; Cartaxo, J. M.

; Dutra, R. P. S.

; Macedo, D. A.

; Campos, L. F. A.

Cerâmica

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Sep 2018, Volumen 64 Nº 371 Paginas 381 - 387

Resumen: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo A pesca de mariscos é uma das atividades comerciais mais importantes da comunidade pesqueira do município de Cabedelo (Paraíba, Brasil). O processo de beneficiamento, após a extração do molusco, gera elevada quantidade de conchas, cujo descarte, em volume considerável, provoca assoreamento de áreas extensas e consequente desequilíbrio ambiental. Na busca do aproveitamento desses resíduos (conchas de mariscos) e visando a redução dos problemas ambientais causados, esse trabalho teve como objetivo o estudo da incorporação de pó de conchas de mariscos em massa de porcelanato. Composições cerâmicas foram formuladas a partir de uma massa de porcelanato industrial e pó de concha de marisco ou CaCO3 comercial variando entre 0 e 7% em massa. Corpos de prova preparados por prensagem uniaxial tiveram suas propriedades tecnológicas avaliadas em função da temperatura de sinterização. Os resultados indicaram que o uso de até 7% em massa de pó de concha mantém as propriedades tecnológicas dentro dos padrões exigidos pela ABNT (Brasil) para a classificação como cerâmicas de revestimento do grupo BIa.

Abstract The fishing of shellfish is one of the most important commercial activities of the fishing community of the municipality of Cabedelo (Paraíba, Brazil). The step of processing, after the extraction of the mollusk, generates a large amount of shells, whose discharge, in considerable volume, causes silting of large areas and consequent environmental imbalance. In the search for the use of these residues (mollusk shells) and aiming at reducing the environmental problems caused, this work had the aim of studying the incorporation of mollusk shell powder in the mass of porcelain tile. Ceramic compositions were formulated from an industrial standard mass and mollusk shell powder or commercial CaCO3 ranging from 0 to 7% by weight. Samples prepared by uniaxial pressing had their technological properties evaluated as a function of the sintering temperature. The results indicated that the use of up to 7 wt% of the mollusk shell powder maintains the technological properties within the standards required by the ABNT (Brazil) for classification as BIa type porcelain tiles.

https://doi.org/10.1590/0366-69132018643712368 1686 descargas

14.

Sharp Rejection and Wide Stopband Microstrip Lowpass Filters using Complementary Split Ring Resonators
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da Costa, I. F.

; Campos, A. L. P. S.

; Gomes Neto, A.

Journal of Microwaves, Optoelectronics and Electromagnetic Applications

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Mar 2018, Volumen 17 Nº 1 Paginas 134 - 143

Resumen: En | Texto: En | PDF: En

Abstract Chebyshev microstrip lowpass filters with improved performance, achieved by means of circular complementary split ring resonators (CSRR), are presented. CSRR particles exhibit frequency rejection bandwidths in the vicinity of their resonant frequencies that can be used to meliorate both selectivity and stopband in microstrip lowpass filters. Two configurations have been used: a stepped-impedance model and a configuration using open-circuited stubs. Microstrip filters having 5, 7 and 9 poles were designed and fabricated. Selectivity values up to 86 dB/GHz and suppression levels reaching 60 dB in the stopband were obtained. The filters have cutoff frequency around 2 GHz and rejection band up to 10 GHz. The insertion of the designed CSRR resonators in the ground plane of the filters removes all the transmission spurious observed in the analyzed frequency band. No considerable variation in the passband group delay is observed in the CSRR-based lowpass filters. A comparison is made among the filters designed in this and other referenced works, considering their number of poles and size. The measured results are in good agreement with the simulated ones. The presented filters can be candidates for applications using the VHF, UHF and L bands, being also very effective in the rejection of the S and C bands. Applications that demand the rejection of the first half of the X band can also use the filters detailed in this paper.

https://doi.org/10.1590/2179-10742018v17i11101 792 descargas

15.

Brazilian Guidelines for Hereditary Angioedema Management - 2017 Update Part 1: Definition, Classification and Diagnosis
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Giavina-Bianchi, Pedro

; Arruda, Luisa Karla

; Aun, Marcelo V.

; Campos, Regis A.

; Chong-Neto, Herberto J.

; Constantino-Silva, Rosemeire N.

; Fernandes, Fátima R.

; Ferraro, Maria F.

; Ferriani, Mariana P.L.

; França, Alfeu T.

; Fusaro, Gustavo

; Garcia, Juliana F.B.

; Komninakis, Shirley

; Maia, Luana S.M.

; Mansour, Eli

; Moreno, Adriana S.

; Motta, Antonio A.

; Pesquero, João B.

; Portilho, Nathalia

; Rosário, Nelson A.

; Serpa, Faradiba S.

; Solé, Dirceu

; Takejima, Priscila

; Toledo, Eliana

; Valle, Solange O.R.

; Veronez, Camila L.

; Grumach, Anete S.

Clinics

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2018, Volumen 73 elocation e310

Resumen: En | Texto: En | PDF: En

Hereditary angioedema is an autosomal dominant disease characterized by recurrent angioedema attacks with the involvement of multiple organs. The disease is unknown to many health professionals and is therefore underdiagnosed. Patients who are not adequately diagnosed and treated have an estimated mortality rate ranging from 25% to 40% due to asphyxiation by laryngeal angioedema. Intestinal angioedema is another important and incapacitating presentation that may be the main or only manifestation during an attack. In this article, a group of experts from the “Associação Brasileira de Alergia e Imunologia (ASBAI)” and the “Grupo de Estudos Brasileiro em Angioedema Hereditário (GEBRAEH)” has updated the Brazilian guidelines for the diagnosis and treatment of hereditary angioedema.

https://doi.org/10.6061/clinics/2018/e310 1717 descargas

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