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1.
Detection of Eyebolt Faults Using a Random Forest Ensemble Model Based on Multiple High-Frequency Electromagnetic Parameters HighFrequency High Frequency
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Silva Filho, H. V. H.
; Santos, R.G. M. dos
; Barbosa, Douglas C. P.
; Melo, M. T. de
; Novo, Lauro R. G. S. Lourenço
.
Journal of Microwaves, Optoelectronics and Electromagnetic Applications
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Abstract This paper presents an eyebolt structural fault detection system, based on the analysis of multiple electromagnetic parameters through a random forest classifier trained by both measurements and high-fidelity simulated signals. The proposed methodology is completely noninvasive and does not require the disassembly of the electrical infrastructure, allowing the live-line working. The obtained results show that the proposed multi-parameter strategy achieves high accuracy and increases the system’s capability of detecting faults, improving the efficiency of the operator’s preventive maintenance routines and, consequently, increasing the reliability of the power supply and energy distribution systems. system highfidelity fidelity signals infrastructure liveline live line working multiparameter multi parameter systems s faults operators operator consequently
2.
Anti-erosion effect of an experimental varnish on eroded dentin
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Monteiro Filho, George
; Barros, Antonia Patricia Oliveira
; Fernandes, Gabriela Carvalho Santos
; Jassé, Fernanda Ferreira de Albuquerque
; Kuga, Milton Carlos
; Alencar, Cristiane de Melo
.
Abstract This in vitro study evaluated the effect of an experimental varnish containing 20% nano-hydroxyapatite (nHAP) associated with 5% stannous chloride (SnCl2) against erosive-abrasive wear on bovine dentin. Samples of bovine cervical dentin were pre-eroded (0.3% citric acid, pH 2.6 for 10 minutes) and randomized into 4 groups (n=10): Control group - experimental varnish without active ingredient (CG); experimental varnish containing 20% nHAP (nHG); experimental varnish containing 5% SnCl2 (24.800 ppm Sn2+) (SnG); experimental varnish containing 20% nHAP associated with 5% SnCl2 (18.300 ppm Sn2+) (nHSnG). After applying the materials, the erosive-abrasive challenges were performed for five days. Erosive dentin loss and analysis of the pattern of dentinal obliteration were performed by 3D confocal laser microscopy. A one-way ANOVA/Bonferroni test was performed to analyze the data (α=0.05). The SnG and nHSnG experimental groups presented more effectiveness in preventing erosive wear when compared to the other groups (p<0.05). There was no statistically significant difference between the SnG and nHSnG groups (p = 0.731) in tooth structure dentin loss. Regarding the amount of open dentinal tubules, the highest amount of obstructed dentinal tubules was demonstrated in SnG and nHSnG (p < 0.05) when compared to the others. Between SnG and nHSnG there was no significant difference (p = 0.952) in the amount of closed dentinal tubules in the dentin. Experimental varnishes containing 5% SnCl2 associated or not with 20% nHAP showed to be a promising strategy in preventing erosive-abrasive wear of dentin. In addition, nHSnG was able to obliterate dentinal tubules.
Resumo Este estudo in vitro avaliou o efeito de um verniz experimental contendo 20% de nano-hidroxiapatita (nHAP) associado a 5% de cloreto estanoso (SnCl2) contra o desgaste erosivo-abrasivo da dentina bovina. As amostras de dentina cervical bovina foram pré-erodificadas (0,3% de ácido cítrico, pH 2,6 durante 10 minutos) e aleatorizadas em 4 grupos (n=10): Grupo controle - verniz experimental sem ingrediente ativo (GC); verniz experimental contendo 20% nHAP (GnH); verniz experimental contendo 5% SnCl2 (24.800 ppm Sn2+) (GSn); verniz experimental contendo 20% nHAP associado a 5% SnCl2 (18.300 ppm Sn2+) (GnHSn). Após a aplicação dos materiais, os desafios erosivo-abrasivos foram realizados durante cinco dias. Perda de dentina erosiva e análise do padrão de obliteração dentinária foram realizadas por microscopia laser confocal 3D. Foi realizado o teste ANOVA/Bonferroni unidireccional para analisar os dados (α=0,05). Os grupos experimentais GSn e GnHSn apresentaram maior eficácia na prevenção do desgaste erosivo quando comparados com os outros grupos (p<0,05). Não houve diferença estatisticamente significativa entre os grupos GSn e GnHSn (p = 0,731) na perda de dentina da estrutura dentária. Relativamente à quantidade de túbulos dentinários abertos, a maior quantidade de túbulos dentinários obstruídos foi demonstrada em GSn e GnHSn (p < 0,05) quando comparada com os outros grupos. Entre GSn e GnHSn, não houve diferença significativa (p = 0,952) na quantidade de túbulos dentinários fechados na dentina. Os vernizes experimentais contendo 5% de SnCl2 associados ou não a 20% de nHAP mostraram ser uma estratégia promissora na prevenção do desgaste erosivo-abrasivo da dentina. Além disso, o GnHSn conseguiu obliterar os túbulos dentinários.
3.
Pre-slaughter management in Northeast Brazil and the effects on thermophysiological indicators in pigs and pH45
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Melo, Kilvia K. de S. V.
; Machado, Nítalo A. F.
; Barbosa Filho, José A. D.
; Peixoto, Maria S. M.
; Andrade, Ana P. C. de
; Costa, Jennifer A. da
; Oliveira, Ana B. A.
; Sales, João J. de M.
.
Revista Brasileira de Engenharia Agrícola e Ambiental
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RESUMO Práticas inadequadas de manejo antes do abate podem comprometer o bem-estar animal e a qualidade da carne suína. Este estudo visou avaliar os efeitos do período de transporte (TT), período de descarga (TD), e período de pré-abate (TE) nos indicadores termofisiológicos animais e no pH da carne suína, utilizando uma abordagem multivariada. Este estudo foi realizado num matadouro localizado em Aquiraz, Ceará, Brasil. Um total de 60 suínos mestiços com 107 ± 5 kg de peso corporal foram distribuídos em três grupos experimentais: grupo A (TT = 180 min, TD ≤ 10 min, e TE = 24 horas), grupo B (TT = 60 min, TD ≤ 15 min, e TE = 18 horas), e grupo C (TT = 45 min, TD ≤ 5 min, e TE = 24 horas). A análise discriminante canônica foi implementada e as diferenças entre tratamentos são representadas graficamente. Os dois primeiros componentes foram responsáveis por 97% dos tratamentos. A análise discriminante mostrou que o grupo C apresentou diferenças multivariadas em relação aos outros, particularmente com temperatura retal elevada antes do abate (38,4 ± 0,23 °C) e frequência respiratória (131 ± 7,0 respirações min-1) e temperatura retal (39,7 ± 0,18 °C) à chegada ao matadouro. O período de transporte (TT), período de descarga (TD) e o stress térmico das instalações influenciaram variáveis fisiológicas, tais como a temperatura retal e a frequência respiratória. Além disso, as variáveis de estresse fisiológico também favoreceram cortes com pH básico, resultando em perda de qualidade.
ABSTRACT Inadequate pre-slaughter handling practices may compromise animal welfare and pork quality. This study aimed to evaluate the effects of transport period (TT), unloading period (UT), and pre-slaughtering period (WT) on animal thermophysiological indicators and pork pH using a multivariate approach. This study was conducted in a slaughterhouse located in Aquiraz, Ceará state, Brazil. A total of 60 mestizo pigs with 107 ± 5 kg body weight were distributed into three experimental groups: group A (TT = 180 min, UT ≤ 10 min, and WT = 24 hours), group B (TT = 60 min, UT ≤ 15 min, and WT = 18 hours), and group C (TT = 45 min, UT ≤ 5 min, and WT = 24 hours). Canonical discriminant analysis was implemented and the differences between treatments are represented graphically. The first two components accounted for 97% treatments. The discriminant analysis showed that group C presented multivariate differences in relation to others, particularly with high rectal temperature before slaughter (38.4 ± 0.23 °C) and respiratory rate (131 ± 7.0 breaths min-1) and rectal temperature (39.7 ± 0.18 °C) upon arrival at the slaughterhouse. Transport period (TT), unloading period (UT), and thermal stress of the facilities influenced physiological variables, such as rectal temperature and respiratory rate. Furthermore, the physiological stress variables also favored cuts with basic pH, resulting in quality loss.
4.
The impact of bariatric and metabolic surgery on the morbidity and mortality of patients infected during the COVID-19 pandemic: a retrospective cohort study
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Costa, Luiz Henrique Sala de Melo
; Costa, Luiz Filipe Sala de Melo
; Kachan, Gabriela Rezende
; Gentile, João Kleber de Almeida
; Mendonça Filho, Raul Andrade
; Costa, Marcela Ralin de Carvalho Deda
; Ribas Filho, Jurandir Marcondes
.
ABSTRACT BACKGROUND: Since the impact of the coronavirus disease 2019 (COVID-19) pandemic in March 2020, several studies have shown a strong relationship between obesity and severe cases of COVID-19. It is imperative to assess whether bariatric surgery exerts a protective effect in such cases. OBJECTIVE: This study aimed to assess the impact of bariatric surgery on the morbidity and mortality in obese patients during the COVID-19 pandemic. A comprehensive search was performed using the PubMed and Cochrane Library databases. DESIGN AND SETTING: Retrospective cohort studies conducted in the Faculdade de Medicina da Universidade Cidade de São Paulo, São Paulo (SP), Brazil. METHODS: The search comprised the following descriptors: “bariatric, surgery, COVID-19”. Current retrospective cohort studies that examined the influence of bariatric surgery on the morbidity and mortality of obese patients during the COVID-19 pandemic were considered eligible. RESULTS: After removing duplicates, 184 studies were obtained from the databases. Of these, 181 were excluded from the analysis as they did not meet the eligibility criteria. Patients undergoing postoperative follow-up of bariatric surgery had a similar probability of SARS-CoV-2 infection compared to the general population, and persistent comorbidities were associated with an increased risk and severity of infection. CONCLUSION: Bariatric surgery has a protective effect against severe COVID-19 in the obese population, bringing the prevalence of severe disease cases to levels equivalent to those of the nonobese general population, with a positive impact on morbidity and mortality.
5.
Systematic review on fecal calprotectin in cystic fibrosis
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Lazzarotto, Eduarda Sampaio
; Vasco, Jannaina Ferreira de Melo
; Führ, Fabiane
; Riedi, Carlos Antônio
; Rosário Filho, Nelson Augusto
.
Abstract Objectives: Fecal calprotectin is an inflammatory marker used for monitoring intestinal diseases. It has been studied as a marker of intestinal inflammation in cystic fibrosis (CF), a multi-systemic genetic disease caused by alterations to the CFTR gene. Manifestations of the disease favor a systemic inflammation not limited to the respiratory tract, therefore, calprotectin is a non-invasive and effective diagnostic method. The aim of the study was to perform a systematic review of the literature with a qualitative synthesis of studies. Sources: The articles were selected from PubMed, Web of Science, Scielo and Lilacs. Summary of the findings: Nine studies were selected for that qualitative synthesis, one was a randomized clinical trial, and eight were case-control or cohort designs. Most studies have indicated that calprotectin is a marker of systemic inflammation in CF and not just intestinal inflammation. Calprotectin is an aid in monitoring inflammatory bowel conditions in patients with cystic fibrosis. Conclusion: Further studies should be conducted to investigate the role of this marker in the systemic inflammation of CF.
6.
Photosynthetic pigments and quantum yield of West Indian cherry under salt stress and NPK combinations
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Silva Filho, A. M.
; Costa, D. S.
; Gheyi, H. R.
; Melo, A. S.
; Silva, A. A. R. da
; Nunes, K. G.
; Bonou, S. I.
; Souza, A. R.
; Ferraz, R. L. S.
; Nascimento, R.
.
Abstract West Indian cherry cultivation has proved to be an important economic activity in northeastern Brazil. However, irrigation with brackish waters limits cultivation, requiring new strategies to minimize the effect of salt stress. In this context, the present study aimed to evaluate the effect of nitrogen (N), phosphorus (P), and potassium (K) combinations on the photosynthetic pigments and quantum yield of West Indian cherry cultivated under salt stress, in the second year of production. The assay was conducted in a protected environment by adopting an experimental design in randomized blocks, with treatments distributed in a 2×10 factorial arrangement referring to two electrical conductivity levels of irrigation water - ECw (0.6 and 4.0 dS m-1) and 10 NPK fertilization combinations - FC (80-100-100; 100-100-100; 120-100-100; 140-100-100; 100-80-100; 100-120-100; 100-140-100; 100-100-80; 100-100-120, and 100-100-140% of the recommendation, in the second year of production), with three replications, each consisting of one plant. Irrigation with the electrical conductivity of 4.0 dS m-1 negatively affected the synthesis of photosynthetic pigments and the photochemical efficiency of the West Indian cherry cv. Flor Branca. The NPK combinations did not attenuate the effects of salt stress on the analyzed variables. However, the combinations referring to 120-100-100%, 140-100-100%, and 100-120-100% of NPK recommendation improved the quantum yield of photosystem II by reducing the initial fluorescence and increasing the maximum fluorescence of the West Indian cherry cv. Flor Branca.
Resumo Na região Nordeste do Brasil, o cultivo da acerola tem se mostrado uma importante atividade econômica; entretanto, a irrigação com águas salobras limita o cultivo, sendo necessário a busca por estratégias que minimizem o efeito do estresse salino. Neste contexto, objetivou-se avaliar combinações de adubação com nitrogênio (N), fósforo (P) e potássio (K) sobre os teores de pigmentos fotossintéticos e o rendimento quântico do fotossistema II da aceroleira cv. Flor Branca cultivada sob estresse salino, no segundo ano de produção. O ensaio foi conduzido em ambiente protegido sob delineamento experimental em blocos casualizados, com os tratamentos distribuídos em esquema fatorial 2×10, referentes a dois níveis de condutividade elétrica da água de irrigação - CEa (0,6 e 4,0 dS m-1) e 10 combinações de adubação com NPK - CA (80-100-100; 100-100-100; 120-100-100; 140-100-100; 100-80-100; 100-120-100; 100-140-100; 100-100-80; 100-100-120 e 100-100-140% da recomendação referente ao segundo ano de produção), com três repetições cada uma constituída por uma planta. A irrigação com água de 4,0 dS m-1 de condutividade elétrica reduziu os teores de pigmentos fotossintéticos e o rendimento quântico do fotossistema II da aceroleira. As combinações de NPK não atenuaram os efeitos do estresse salino sobre as variáveis analisadas. Entretanto, as combinações de 120-100-100, 140-100-100 e 100-120-100% da recomendação de NPK melhoraram o rendimento quântico do fotossistema II, uma vez que reduziram a fluorescência inicial e aumentaram a fluorescência máxima da aceroleira cv. Flor Branca.
7.
Reconfigurable Filtenna using Varactor Diode for Wireless Applications
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Araujo, J. A. I.
; Oliveira, M. R. T.
; Cavalcanti Filho, P. H. B.
; Silva, C. P. N.
; Coutinho, M. S.
; Melo, M. T. de
; Llamas-Garro, Ignacio
; Barboza, A. G.
.
Journal of Microwaves, Optoelectronics and Electromagnetic Applications
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Abstract This paper presents a compact and planar reconfigurable filtenna for application in Wireless systems. The filtenna is composed of a UWB circular antenna and a filter with two trapezoidal resonators. The filter is integrated on the antenna feed line and has a band-pass frequency response. The filtenna frequency response reconfiguration is achieved by changing the capacitance of a varactor diode, placed between filter resonators; the capacitance varies continuously from 1.32 pF to 4.09 pF according to an applied bias voltage. The varactor capacitance analog variation defines the filtenna frequency of operation, which can be varied from 2.2 GHz to 3.4 GHz with an average bandwidth of 200 MHz, while maintaining the radiation characteristics of the UWB antenna. Simulated and measured filtenna results are shown according to varactor diode bias, demonstrating multiband operation using a compact planar design.
8.
Cardiac Arrhythmias and Covid-19
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Fagundes, Alexsandro Alves
; Melo, Sissy Lara de
; Armaganijan, Luciana
; Kuniyoshi, Ricardo
; Moraes, Luis Gustavo Belo de
; Borges, Vanessa Alves Guimarães
; Scanavacca, Mauricio
; Martinelli Filho, Martino
; Teixeira, Ricardo Alkmim
.
International Journal of Cardiovascular Sciences
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Abstract Cardiovascular manifestations of COVID-19 include cardiac rhythm disturbances, whose mechanisms, incidence, and most common types are not well established in this population. Intense inflammatory response and metabolic activity contribute to recurrence of pre-existing arrhythmias, and other arrhythmias can occur due to myocardial injury, acute coronary insufficiency, and electrolyte disturbances. Brady- and tachyarrhythmias, as well as conduction disorders have been described. QT interval prolongation and fatal ventricular arrhythmias ( Torsades de Pointes ) may result from the pathological process or adverse effect of drugs (antiarrhythmics, chloroquine / hydroxychloroquine, azithromycin and antivirals). Patients with congenital heart disease and hemodynamic repercussions, patients with signs of heart failure, pulmonary hypertension, cyanosis, hypoxemia, and those who underwent heart transplantation and immunosuppression are at greater risk. In patients with implantable cardioverter-defibrillators (ICDs), the risk depends on the presence of structural heart disease. In the course of COVID-19, in-person assessment of these patients should be limited to high-risk situations, including syncope, worsening of heart failure and shock delivery by ICDs. Likewise, cardiac implantable electronic device implantation or replacement surgery should be limited to emergency and urgent cases, including symptomatic high-degree atrioventricular block, ICD for secondary prevention and pulse generator replacement due to battery drain.
9.
Zooplankton associated with phytotelms and treefrogs in a neotropical forest
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Morais Júnior, Cláudio S. de
; Diniz, Leidiane P.
; Nascimento Filho, Silvano L. do
; Brito, Maiara T. da Silva
; Silva, Adilson de O.
; Moura, Geraldo J. B. de
; Melo Júnior, Mauro de
.
RESUMO Hipóteses sobre a distribuição das comunidades de zooplâncton em vários ecossistemas são muitas vezes limitadas pela falta de dados sobre os seus mecanismos de dispersão. Muitas pesquisas sobre a dispersão passiva mediada por anuros têm sido desenvolvidas em bromélias, porém com foco em ostrácodes e anelídeos. Nós investigamos o potencial para a forésia externa do zooplâncton (rotíferos, cladóceros, copépodes) por anuros arbóreos em fitotelmos de bromélias. Nossa hipótese é que (1) a composição do zooplâncton presente na pele dos anuros e nos fitotelmos das bromélias é semelhante, e que (2) anuros com maior tamanho corporal carregam mais propágulos de invertebrados. Filtramos a água presente nos fitotelmos (10 a 150 mL) usando uma rede de plâncton (45 µm) e fixamos os invertebrados em formol a 4%. Os anuros foram coletados ativamente em torno das bromélias (até ~1,5 m de raio) e depois lavados com água destilada. Quatorze espécies de rotíferos e três de crustáceos foram registradas na água dos fitotelmos e no corpo dos anuros. Capturamos 17 anuros variando de 2 a 5 cm de SLV e pertencentes a cinco espécies: Pristimantis ramagii (Boulenger, 1888), Dendropsophus decipiens (A. Lutz, 1925), Scinax auratus (Wied-Neuwied,1821), S. pachycrus (Miranda-Ribeiro, 1937) e S. x-signatus (Spix, 1824). Entre eles, 12 (70,59%) tinham propágulos aderidos ao corpo, dos quais a maioria (dez indivíduos) apresentou formas ativas de zooplâncton, enquanto apenas dois apresentaram ovos dormentes. Dez rotíferos e duas espécies de microcrustáceos foram registrados aderidas aos anuros. A composição zooplanctônica diferiu entre os fitotelmos e a pele de anuros e, o tamanho do corpo do dispersor não explicou o número de propágulos transportados, refutando ambas as hipóteses. No entanto, ressaltamos que evidências de dispersão foram encontradas devido ao alto número de propágulos aderidos aos anuros. Nosso estudo fornece evidências de que os anuros podem ser potenciais dispersores de formas ativas e inativas de zooplâncton em bromélias, através de forésia externa.
ABSTRACT Assumptions about the distribution of zooplankton communities in various ecosystems are often limited by lack of data on dispersal mechanisms. Many studies on frog-mediated passive dispersal have been developed in bromeliads, but they usually focus on ostracods and annelids. We investigated the potential for external phoresy of zooplankton (rotifers, cladocerans, copepods) by treefrogs in bromeliad phytotelms. Our hypotheses are that (1) zooplankton composition on frogs’ skin and in phytotelm tanks is similar, and (2) frogs with larger body size carry more propagules of these invertebrates. We filtered phytotelm water (10 to 150 mL) using plankton net (45 µm), and fixed invertebrates with 4% formalin. Frogs were actively collected in and around bromeliads (up to ~1.5 m radius) and then washed with distilled water. Fourteen species of rotifers and three of crustaceans were registered in phytotelm water and frog bodies. We captured 17 frogs with a snout-vent length (SVL) ranging from 2 to 5 cm and belonging to five species: Pristimantis ramagii (Boulenger, 1888), Dendropsophus decipiens (A. Lutz, 1925), Scinax auratus (Wied-Neuwied,1821), S. pachycrus (Miranda-Ribeiro, 1937) and S. x-signatus (Spix, 1824). Among them, 12 (70.59%) had propagules adhered to their bodies, of which the majority (ten individuals) had active zooplankton forms, while only two had dormant eggs. Ten rotifer and two microcrustacean species were recorded adhered to frogs. The zooplankton composition differed between phytotelms and anuran skin, and frog body size does not explain the number of propagules carried, refuting both hypotheses. However, evidence of dispersal was found due to the high number of propagules adhered to anurans. Our study provides evidence that frogs may be potential dispersers of dormant and active forms of zooplankton in bromeliads, through external phoresy.
https://doi.org/10.1590/1678-4766e2019020
1550 downloads
10.
Proposta de uma cerâmica obtida por meio de geopolimerização de lodo de ETA calcinado
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Resumo Neste estudo, pelo método de geopolimerização, produziu-se uma cerâmica alternativa utilizando como matéria-prima lodo de estação de tratamento de água (ETA). Primeiramente, esse resíduo foi seco, moído, peneirado e calcinado, sendo caracterizado antes e após tais procedimentos. Com o lodo de ETA devidamente calcinado, a 750 °C por 4 h, produziu-se um geopolímero. Esse material, em estado endurecido, é semelhante a certos tipos de cerâmicas. Os corpos de prova geopoliméricos produzidos foram curados à temperatura ambiente durante 1, 7 e 28 dias. Após a cura, foram caracterizados por meio de difração de raios X, fluorescência de raios X, microscopia eletrônica de varredura e resistência à compressão axial. Curado à temperatura ambiente, o geopolímero atingiu, em média, 20 MPa em apenas 1 dia de idade e 60 MPa aos 28 dias. Constatou-se, portanto, que lodos de ETA podem ser utilizados no desenvolvimento de materiais cerâmicos de elevada resistência mecânica. Com base nos resultados obtidos, sugere-se que o geopolímero produzido possa ser aprimorado e incorporado pelas indústrias de cerâmicas estruturais. O processo adotado, além do baixo consumo energético, mostrou-se uma excelente opção para a destinação de lodos de ETA.
Abstract In this study, by the geopolymerization method, an alternative ceramic was produced using as raw material sludge from water treatment plant (WTP). First, the WTP sludge was dried, milled, sieved and calcined, being characterized before and after such procedures. With the WTP sludge properly calcined, at 750 ° C for 4 h, a geopolymer was produced. The geopolymeric specimens produced was cured at room temperature for 1, 7 and 28 days. After curing, it was characterized by means of X-ray diffraction, X-ray fluorescence, scanning electron microscopy and axial compression strength. Cured at room temperature, the geopolymer reached, on average, 20 MPa in only 1 day of age and 60 MPa at 28 days. It was verified, therefore, that WTP sludge can be used in the development of ceramic materials of high mechanical resistance. Based on the results obtained, it is suggested that the geopolymer produced can be improved and incorporated by the ceramics industries. The process adopted, besides the low energy consumption, proved to be an excellent option for the destination of WTP sludge.
https://doi.org/10.1590/0366-69132018643702353
2394 downloads
11.
Meniscal allograft transplantation in rabbit
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VILELA, LIANA M.
; CARLO, RICARDO J. DEL
; Melo FILHO, EDSON V.
; FAVARATO, LUKIYA S.C.
; DUARTE, TATIANA S.
; PONTES, KELLY C.S.
; CUNHA, DAISE N.Q.
.
Este estudo avaliou a técnica do alotransplante de menisco utilizando enxertos preservados em glicerina a 98%, em coelhos. A eutanásia foi realizada depois de 70 dias para comparar os meniscos transplantados (TM1 a TM16) versus os contralaterais (OM1 a OM16). Dezesseis meniscos, 8 TM transplantados e 8 OM contralaterais foram submetidos à análise macro e histomorfométrica para identificação e quantificação do tipo celular, e para a quantificação e distribuição das fibras colágenas. Um estudo de revascularização foi feito em todas as outras amostras. O comprimento dos OM variou de 0,9 1,0 cm e, em dois TM, foi menor. Todos os TM estavam completamente fixados à membrana sinovial,exceto por um caso que apresentou fixação parcial. Em ambos, TM e OM foi encontrada a mesma quantidade de condrócitos, fibroblastos e fibrócitos, mas os condrócitos estavam predominantes no corno. Em TM, as fibras de colágeno estavam distribuídas de forma organizada em todo o corpo, e desorganizada nos cornos. Em OM, estas fibras estavam bem organizadas. A quantidade de colágeno tipo I e III, e a vascularização do tecido perimeniscal e da borda foram semelhantes em OM e TM. As avaliações mostraram a incorporação do enxerto e recomendam esta técnica de transplante e o método de preservação.
This study evaluated the technique for meniscal allograft transplantation using allografts preserved in glycerin 98% in rabbits. Euthanasia was performed at 70 days to compare the transplanted (TM1 to TM16) versus the contralateral meniscus (OM1 to OM16). Sixteen menisci, 8 transplanted and 8 contralateral, were submitted to gross examination, histomorphometric analysis for identification and quantification of cellular type, and for quantification and distribution of collagen fibers. A revascularization study was conducted in all of the other samples. Lengths of the OM varied from 0.9 to 1.0 cm and two TM were smaller. All TM were completely attached to the synovial membrane, except for one case that presented partial fixation. Both, TM and OM had similar amounts of chondrocytes, fibroblasts and fibrocytes, and at the horns, chondrocytes were predominant. The collagen fibers in TM were well organized throughout the body, and disorganized at the horns. These fibers in OM were organized. The amounts of collagen type I and III, and the vascularization of the perimeniscal tissue and of the edge were similar in OM and TM. These results demonstrated graft integration and thus this transplantation technique and preservation method may be recommended.
https://doi.org/10.1590/0001-3765201520140417
1998 downloads
12.
Growing knowledge: an overview of Seed Plant diversity in Brazil
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Zappi, Daniela C.
; Filardi, Fabiana L. Ranzato
; Leitman, Paula
; Souza, Vinícius C.
; Walter, Bruno M.T.
; Pirani, José R.
; Morim, Marli P.
; Queiroz, Luciano P.
; Cavalcanti, Taciana B.
; Mansano, Vidal F.
; Forzza, Rafaela C.
; Abreu, Maria C.
; Acevedo-Rodríguez, Pedro
; Agra, Maria F.
; Almeida Jr., Eduardo B.
; Almeida, Gracineide S.S.
; Almeida, Rafael F.
; Alves, Flávio M.
; Alves, Marccus
; Alves-Araujo, Anderson
; Amaral, Maria C.E.
; Amorim, André M.
; Amorim, Bruno
; Andrade, Ivanilza M.
; Andreata, Regina H.P.
; Andrino, Caroline O.
; Anunciação, Elisete A.
; Aona, Lidyanne Y.S.
; Aranguren, Yani
; Aranha Filho, João L.M.
; Araújo, Andrea O.
; Araújo, Ariclenes A.M.
; Araújo, Diogo
; Arbo, María M.
; Assis, Leandro
; Assis, Marta C.
; Assunção, Vivian A.
; Athiê-Souza, Sarah M.
; Azevedo, Cecilia O.
; Baitello, João B.
; Barberena, Felipe F.V.A.
; Barbosa, Maria R.V.
; Barros, Fábio
; Barros, Lucas A.V.
; Barros, Michel J.F.
; Baumgratz, José F.A.
; Bernacci, Luis C.
; Berry, Paul E.
; Bigio, Narcísio C.
; Biral, Leonardo
; Bittrich, Volker
; Borges, Rafael A.X.
; Bortoluzzi, Roseli L.C.
; Bove, Cláudia P.
; Bovini, Massimo G.
; Braga, João M.A.
; Braz, Denise M.
; Bringel Jr., João B.A.
; Bruniera, Carla P.
; Buturi, Camila V.
; Cabral, Elza
; Cabral, Fernanda N.
; Caddah, Mayara K.
; Caires, Claudenir S.
; Calazans, Luana S.B.
; Calió, Maria F.
; Camargo, Rodrigo A.
; Campbell, Lisa
; Canto-Dorow, Thais S.
; Carauta, Jorge P.P.
; Cardiel, José M.
; Cardoso, Domingos B.O.S.
; Cardoso, Leandro J.T.
; Carneiro, Camila R.
; Carneiro, Cláudia E.
; Carneiro-Torres, Daniela S.
; Carrijo, Tatiana T.
; Caruzo, Maria B.R.
; Carvalho, Maria L.S.
; Carvalho-Silva, Micheline
; Castello, Ana C.D.
; Cavalheiro, Larissa
; Cervi, Armando C.
; Chacon, Roberta G.
; Chautems, Alain
; Chiavegatto, Berenice
; Chukr, Nádia S.
; Coelho, Alexa A.O.P.
; Coelho, Marcus A.N.
; Coelho, Rubens L.G.
; Cordeiro, Inês
; Cordula, Elizabeth
; Cornejo, Xavier
; Côrtes, Ana L.A.
; Costa, Andrea F.
; Costa, Fabiane N.
; Costa, Jorge A.S.
; Costa, Leila C.
; Costa-e-Silva, Maria B.
; Costa-Lima, James L.
; Cota, Maria R.C.
; Couto, Ricardo S.
; Daly, Douglas C.
; De Stefano, Rodrigo D.
; De Toni, Karen
; Dematteis, Massimiliano
; Dettke, Greta A.
; Di Maio, Fernando R.
; Dórea, Marcos C.
; Duarte, Marília C.
; Dutilh, Julie H.A.
; Dutra, Valquíria F.
; Echternacht, Lívia
; Eggers, Lilian
; Esteves, Gerleni
; Ezcurra, Cecilia
; Falcão Junior, Marcus J.A.
; Feres, Fabíola
; Fernandes, José M.
; Ferreira, D.M.C.
; Ferreira, Fabrício M.
; Ferreira, Gabriel E.
; Ferreira, Priscila P.A.
; Ferreira, Silvana C.
; Ferrucci, Maria S.
; Fiaschi, Pedro
; Filgueiras, Tarciso S.
; Firens, Marcela
; Flores, Andreia S.
; Forero, Enrique
; Forster, Wellington
; Fortuna-Perez, Ana P.
; Fortunato, Reneé H.
; Fraga, Cléudio N.
; França, Flávio
; Francener, Augusto
; Freitas, Joelcio
; Freitas, Maria F.
; Fritsch, Peter W.
; Furtado, Samyra G.
; Gaglioti, André L.
; Garcia, Flávia C.P.
; Germano Filho, Pedro
; Giacomin, Leandro
; Gil, André S.B.
; Giulietti, Ana M.
; A.P.Godoy, Silvana
; Goldenberg, Renato
; Gomes da Costa, Géssica A.
; Gomes, Mário
; Gomes-Klein, Vera L.
; Gonçalves, Eduardo Gomes
; Graham, Shirley
; Groppo, Milton
; Guedes, Juliana S.
; Guimarães, Leonardo R.S.
; Guimarães, Paulo J.F.
; Guimarães, Elsie F.
; Gutierrez, Raul
; Harley, Raymond
; Hassemer, Gustavo
; Hattori, Eric K.O.
; Hefler, Sonia M.
; Heiden, Gustavo
; Henderson, Andrew
; Hensold, Nancy
; Hiepko, Paul
; Holanda, Ana S.S.
; Iganci, João R.V.
; Imig, Daniela C.
; Indriunas, Alexandre
; Jacques, Eliane L.
; Jardim, Jomar G.
; Kamer, Hiltje M.
; Kameyama, Cíntia
; Kinoshita, Luiza S.
; Kirizawa, Mizué
; Klitgaard, Bente B.
; Koch, Ingrid
; Koschnitzke, Cristiana
; Krauss, Nathália P.
; Kriebel, Ricardo
; Kuntz, Juliana
; Larocca, João
; Leal, Eduardo S.
; Lewis, Gwilym P.
; Lima, Carla T.
; Lima, Haroldo C.
; Lima, Itamar B.
; Lima, Laíce F.G.
; Lima, Laura C.P.
; Lima, Leticia R.
; Lima, Luís F.P.
; Lima, Rita B.
; Lírio, Elton J.
; Liro, Renata M.
; Lleras, Eduardo
; Lobão, Adriana
; Loeuille, Benoit
; Lohmann, Lúcia G.
; Loiola, Maria I.B.
; Lombardi, Julio A.
; Longhi-Wagner, Hilda M.
; Lopes, Rosana C.
; Lorencini, Tiago S.
; Louzada, Rafael B.
; Lovo, Juliana
; Lozano, Eduardo D.
; Lucas, Eve
; Ludtke, Raquel
; Luz, Christian L.
; Maas, Paul
; Machado, Anderson F.P.
; Macias, Leila
; Maciel, Jefferson R.
; Magenta, Mara A.G.
; Mamede, Maria C.H.
; Manoel, Evelin A.
; Marchioretto, Maria S.
; Marques, Juliana S.
; Marquete, Nilda
; Marquete, Ronaldo
; Martinelli, Gustavo
; Martins da Silva, Regina C.V.
; Martins, Ângela B.
; Martins, Erika R.
; Martins, Márcio L.L.
; Martins, Milena V.
; Martins, Renata C.
; Matias, Ligia Q.
; Maya-L., Carlos A.
; Mayo, Simon
; Mazine, Fiorella
; Medeiros, Debora
; Medeiros, Erika S.
; Medeiros, Herison
; Medeiros, João D.
; Meireles, José E.
; Mello-Silva, Renato
; Melo, Aline
; Melo, André L.
; Melo, Efigênia
; Melo, José I.M.
; Menezes, Cristine G.
; Menini Neto, Luiz
; Mentz, Lilian A.
; Mezzonato, A.C.
; Michelangeli, Fabián A.
; Milward-de-Azevedo, Michaele A.
; Miotto, Silvia T.S.
; Miranda, Vitor F.O.
; Mondin, Cláudio A.
; Monge, Marcelo
; Monteiro, Daniele
; Monteiro, Raquel F.
; Moraes, Marta D.
; Moraes, Pedro L.R.
; Mori, Scott A.
; Mota, Aline C.
; Mota, Nara F.O.
; Moura, Tania M.
; Mulgura, Maria
; Nakajima, Jimi N.
; Nardy, Camila
; Nascimento Júnior, José E.
; Noblick, Larry
; Nunes, Teonildes S.
; O'Leary, Nataly
; Oliveira, Arline S.
; Oliveira, Caetano T.
; Oliveira, Juliana A.
; Oliveira, Luciana S.D.
; Oliveira, Maria L.A.A.
; Oliveira, Regina C.
; Oliveira, Renata S.
; Oliveira, Reyjane P.
; Paixão-Souza, Bruno
; Parra, Lara R.
; Pasini, Eduardo
; Pastore, José F.B.
; Pastore, Mayara
; Paula-Souza, Juliana
; Pederneiras, Leandro C.
; Peixoto, Ariane L.
; Pelissari, Gisela
; Pellegrini, Marco O.O.
; Pennington, Toby
; Perdiz, Ricardo O.
; Pereira, Anna C.M.
; Pereira, Maria S.
; Pereira, Rodrigo A.S.
; Pessoa, Clenia
; Pessoa, Edlley M.
; Pessoa, Maria C.R.
; Pinto, Luiz J.S.
; Pinto, Rafael B.
; Pontes, Tiago A.
; Prance, Ghillean T.
; Proença, Carolyn
; Profice, Sheila R.
; Pscheidt, Allan C.
; Queiroz, George A.
; Queiroz, Rubens T.
; Quinet, Alexandre
; Rainer, Heimo
; Ramos, Eliana
; Rando, Juliana G.
; Rapini, Alessandro
; Reginato, Marcelo
; Reis, Ilka P.
; Reis, Priscila A.
; Ribeiro, André R.O.
; Ribeiro, José E.L.S.
; Riina, Ricarda
; Ritter, Mara R.
; Rivadavia, Fernando
; Rocha, Antônio E.S.
; Rocha, Maria J.R.
; Rodrigues, Izabella M.C.
; Rodrigues, Karina F.
; Rodrigues, Rodrigo S.
; Rodrigues, Rodrigo S.
; Rodrigues, Vinícius T.
; Rodrigues, William
; Romaniuc Neto, Sérgio
; Romão, Gerson O.
; Romero, Rosana
; Roque, Nádia
; Rosa, Patrícia
; Rossi, Lúcia
; Sá, Cyl F.C.
; Saavedra, Mariana M.
; Saka, Mariana
; Sakuragui, Cássia M.
; Salas, Roberto M.
; Sales, Margareth F.
; Salimena, Fatima R.G.
; Sampaio, Daniela
; Sancho, Gisela
; Sano, Paulo T.
; Santos, Alessandra
; Santos, Élide P.
; Santos, Juliana S.
; Santos, Marianna R.
; Santos-Gonçalves, Ana P.
; Santos-Silva, Fernanda
; São-Mateus, Wallace
; Saraiva, Deisy P.
; Saridakis, Dennis P.
; Sartori, Ângela L.B.
; Scalon, Viviane R.
; Schneider, Ângelo
; Sebastiani, Renata
; Secco, Ricardo S.
; Senna, Luisa
; Senna-Valle, Luci
; Shirasuna, Regina T.
; Silva Filho, Pedro J.S.
; Silva, Anádria S.
; Silva, Christian
; Silva, Genilson A.R.
; Silva, Gisele O.
; Silva, Márcia C.R.
; Silva, Marcos J.
; Silva, Marcos J.
; Silva, Otávio L.M.
; Silva, Rafaela A.P.
; Silva, Saura R.
; Silva, Tania R.S.
; Silva-Gonçalves, Kelly C.
; Silva-Luz, Cíntia L.
; Simão-Bianchini, Rosângela
; Simões, André O.
; Simpson, Beryl
; Siniscalchi, Carolina M.
; Siqueira Filho, José A.
; Siqueira, Carlos E.
; Siqueira, Josafá C.
; Smith, Nathan P.
; Snak, Cristiane
; Soares Neto, Raimundo L.
; Soares, Kelen P.
; Soares, Marcos V.B.
; Soares, Maria L.
; Soares, Polyana N.
; Sobral, Marcos
; Sodré, Rodolfo C.
; Somner, Genise V.
; Sothers, Cynthia A.
; Sousa, Danilo J.L.
; Souza, Elnatan B.
; Souza, Élvia R.
; Souza, Marcelo
; Souza, Maria L.D.R.
; Souza-Buturi, Fátima O.
; Spina, Andréa P.
; Stapf, María N.S.
; Stefano, Marina V.
; Stehmann, João R.
; Steinmann, Victor
; Takeuchi, Cátia
; Taylor, Charlotte M.
; Taylor, Nigel P.
; Teles, Aristônio M.
; Temponi, Lívia G.
; Terra-Araujo, Mário H.
; Thode, Veronica
; Thomas, W.Wayt
; Tissot-Squalli, Mara L.
; Torke, Benjamin M.
; Torres, Roseli B.
; Tozzi, Ana M.G.A.
; Trad, Rafaela J.
; Trevisan, Rafael
; Trovó, Marcelo
; Valls, José F.M.
; Vaz, Angela M.S.F.
; Versieux, Leonardo
; Viana, Pedro L.
; Vianna Filho, Marcelo D.M.
; Vieira, Ana O.S.
; Vieira, Diego D.
; Vignoli-Silva, Márcia
; Vilar, Thaisa
; Vinhos, Franklin
; Wallnöfer, Bruno
; Wanderley, Maria G.L.
; Wasshausen, Dieter
; Watanabe, Maurício T.C.
; Weigend, Maximilian
; Welker, Cassiano A.D.
; Woodgyer, Elizabeth
; Xifreda, Cecilia C.
; Yamamoto, Kikyo
; Zanin, Ana
; Zenni, Rafael D.
; Zickel, Carmem S
.
Resumo Um levantamento atualizado das plantas com sementes e análises relevantes acerca desta biodiversidade são apresentados. Este trabalho se iniciou em 2010 com a publicação do Catálogo de Plantas e Fungos e, desde então vem sendo atualizado por mais de 430 especialistas trabalhando online. O Brasil abriga atualmente 32.086 espécies nativas de Angiospermas e 23 espécies nativas de Gimnospermas e estes novos dados mostram um aumento de 3% da riqueza em relação a 2010. A Amazônia é o Domínio Fitogeográfico com o maior número de espécies de Gimnospermas, enquanto que a Floresta Atlântica possui a maior riqueza de Angiospermas. Houve um crescimento considerável no número de espécies e nas taxas de endemismo para a maioria dos Domínios (Caatinga, Cerrado, Floresta Atlântica, Pampa e Pantanal), com exceção da Amazônia que apresentou uma diminuição de 2,5% de endemicidade. Entretanto, a maior parte das plantas com sementes que ocorrem no Brasil (57,4%) é endêmica deste território. A proporção de formas de vida varia de acordo com os diferentes Domínios: árvores são mais expressivas na Amazônia e Floresta Atlântica do que nos outros biomas, ervas são dominantes no Pampa e as lianas apresentam riqueza expressiva na Amazônia, Floresta Atlântica e Pantanal. Este trabalho não só quantifica a biodiversidade brasileira, mas também indica as lacunas de conhecimento e o desafio a ser enfrentado para a conservação desta flora.
Abstract An updated inventory of Brazilian seed plants is presented and offers important insights into the country's biodiversity. This work started in 2010, with the publication of the Plants and Fungi Catalogue, and has been updated since by more than 430 specialists working online. Brazil is home to 32,086 native Angiosperms and 23 native Gymnosperms, showing an increase of 3% in its species richness in relation to 2010. The Amazon Rainforest is the richest Brazilian biome for Gymnosperms, while the Atlantic Rainforest is the richest one for Angiosperms. There was a considerable increment in the number of species and endemism rates for biomes, except for the Amazon that showed a decrease of 2.5% of recorded endemics. However, well over half of Brazillian seed plant species (57.4%) is endemic to this territory. The proportion of life-forms varies among different biomes: trees are more expressive in the Amazon and Atlantic Rainforest biomes while herbs predominate in the Pampa, and lianas are more expressive in the Amazon, Atlantic Rainforest, and Pantanal. This compilation serves not only to quantify Brazilian biodiversity, but also to highlight areas where there information is lacking and to provide a framework for the challenge faced in conserving Brazil's unique and diverse flora.
https://doi.org/10.1590/2175-7860201566411
33340 downloads
13.
Assessment of heavy metal residues in Brazilian poultry and swine tissue
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Arquivo Brasileiro de Medicina Veterinária e Zootecnia
- Journal Metrics
Objetivou-se investigar a presença de resíduos de arsênico, chumbo e cádmio em amostras de fígado, rins e músculo de aves e suínos, durante os anos de 2002 a 2008. Um total de 1.978 amostras foi analisado: 1031 de aves e 947 de suínos provenientes de matadouros brasileiros. As amostras foram analisadas no Laboratório Nacional Agropecuário (Lanagro), sendo utilizada a técnica de espectrometria de absorção atômica. Em aves, os resíduos de arsênico foram detectados em 53,6% das amostras de fígado, embora sem exceder o LMR. Nos rins, 39,7% das amostras mostraram resíduos mensuráveis e não houve violação dos limites. Em relação ao chumbo, cinco amostras de fígado e 24 de amostras de rins estavam contaminadas (1,5 e 3,6%, respectivamente). No tecido muscular, houve apenas uma amostra com resíduos. Para o cádmio, 3,8% das amostras apresentavam valores abaixo do LMR. Resíduos de cádmio foram encontrados em 110 amostras de rins (16,3% testados), mas apenas uma ultrapassou o limite máximo permitido pela legislação nacional. Em suínos, resíduos de arsênico foram detectados em 15,3% das amostras de fígado, sem exceder o LMR. Nos rins, 14,2% das amostras apresentaram resíduos mensuráveis, sem, no entanto, haver violação dos limites. No que diz respeito aos níveis de chumbo, sete amostras de fígado e 18 amostras de rins estavam contaminadas (2,6 e 2,7%, respectivamente). O cádmio foi encontrado abaixo do LMR em 14,9% das amostras analisadas. Nos rins, 448 amostras (67,8% do total analisado) tinham resíduos de cádmio e quatro amostras excederam o LMR. Durante os sete anos de estudo (2002-2008), apenas cinco (0,25%) das 1.978 amostras analisadas (de aves e suínos) violaram a lei brasileira. Entretanto, mesmo com baixos níveis de violação, o controle é essencial, uma vez que o número de amostras com resíduos foi muitas vezes maior do que o número de violações e, em alguns casos, como o cádmio nos rins, a maioria das amostras continha resíduos quantificáveis e com níveis, muitas vezes, perto do LMR.
The aim of this study was to investigate the presence of arsenic, lead and cadmium residues in samples of liver, kidney and muscle of poultry and swine during the years from 2002 to 2008. A total of 1978 samples were analyzed: 1031 of poultry and 947 of swine from Brazilian slaughterhouses. The samples were analyzed at the National Agricultural Laboratory using the atomic absorption spectrometry technique. In poultry, the arsenic residues were detected in 53.6% of liver samples, although no results have exceeded the MRL. In kidneys, 39.7% of the samples showed measurable residues and there was no violation of the limits. Regarding lead, there were 5 contaminated liver samples and 24 contaminated kidney samples (1.5 and 3.6% respectively). In muscle tissue there was only one sample with residues. For cadmium, 3.8% of the samples were found below MRL. Cadmium residues were found in 110 kidney samples (16.3% of tested), but only one exceeded the legislation limits. In swine, arsenic residues were detected in 15.3% of liver samples, although no results exceeded the MRL. In kidneys, 14.2% of samples showed measurable residues. However, there was no violation of limits. Regarding lead levels, 7 liver samples and 18 kidney samples were contaminated (2.6 and 2.7% respectively). Cadmium was found below MRL in 14.9% of the analyzed samples. In kidneys, 448 samples (67.8% of the total tested) had cadmium residues and 4 samples exceeded the legislation limits. During the seven years of study (2002-2008), only 5 (0.25%) out of 1978 tested samples violated the Brazilian law. However, even with low levels of violation, monitoring is essential, since the number of samples with residues was often greater than the number of violations, and in some cases, such as cadmium in the kidneys, the majority of samples contained quantifiable residues and with levels often near the limits.
https://doi.org/10.1590/1678-41626990
2540 downloads
14.
High performance maleated lignocellulose epicarp fibers for copper ion removal
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Vieira, A. P.
; Santana, S. A. A.
; Bezerra, C. W. B.
; Silva, H. A. S.
; Santos, K. C. A.
; Melo, J. C. P.
; Silva Filho, E. C.
; Airoldi, C.
.
Natural lignocellulosic fiber epicarp extracted from the babassu coconut (Orbignya speciosa) was chemically modified through reaction with molten maleic anhydride without solvent, with incorporation of 189.34 mg g-1 of carboxylic acid groups into the biopolymer structure. The success of this reaction was also confirmed by the presence of carboxylic acid bands at 1741 and 1164 cm-1 in the infrared spectrum. Identically, the same group is observed through 13C NMR CP/MAS in the solid state, via high field signals in the 167 pm region. Both the precursor and the immobilized maleated biopolymers presented nearly the same thermal stability and similar crystallinity to cellulose. However, the pendant carboxylic groups have the ability to remove copper with maximum sorption through a batchwise process at pH 6.0, as expected from the point of zero charge, determined to be 6.45. The sorption kinetic data were fitted to pseudo-first order, pseudo-second order, Elovich-chemisorption and intra-particle diffusion models and the equilibrium data were fitted to the Langmuir, the Freundlich and Tenkim isotherm models. Taking into account a statistical error function and determination coefficients, the data were fit to the pseudo-first and pseudo-second order kinetic and Langmuir isotherm models, with a maximum sorption capacity of copper ions of 55.09 mg g-1. This value suggests the application of this biopolymer with incorporated carboxylate groups as a favorable agent for copper removal from appropriate systems.
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Cited 3 times in SciELO
15.
Punching resistance of internal slab-column connections with double-headed shear studs
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Oliveira, M. H.
; Pereira Filho, M. J. M.
; Oliveira, D. R. C.
; Ferreira, M. P.
; Melo, G. S. S. A.
.
A punção é uma forma de ruptura por cisalhamento que pode ocorrer em ligações laje-pilar que pode ser evitada utilizando-se armaduras de cisalhamento na ligação. Este artigo apresenta comparações entre resultados experimentais de 36 ensaios realizados em ligações laje-pilar interno, armadas com conectores de cisalhamento do tipo pino de duas cabeças, populares na América do Norte, Europa e Ásia, com resultados teóricos utilizando as recomendações do ACI 318, NBR 6118, Eurocode 2, além da Teoria da Fissura Crítica de Cisalhamento (TFCC). Para o banco de dados utilizado, o ACI 318 mostrou tendências conservadoras, enquanto que a NBR 6118 mostrou baixo coeficiente de variação, mas um grande número de resultados contra a segurança. Tanto o Eurocode 2, quanto a TFCC apresentaram resultados satisfatórios, com o Eurocode 2 apresentando desempenho ligeiramente superior.
Punching shear is a brittle failure mode that may occur in slab-column connections, which may be prevented by using shear reinforcement in the slab-column connection. This paper presents comparisons between experimental results of 36 tests in internal slab-column connections with double- headed shear studs, which are largely used in North America, Europe and Asia, with theoretical results using recommendations presented by ACI 318, NBR6118, Eurocode 2 and also the Critical Shear Crack Theory (CSCT).Considering the database used it is possible to observe that ACI 318 presents conservative trends, whereas NBR 6118 showed a low coefficient of variation, but with a large number of unsafe results. Both Eurocode 2 and CSCT showed satisfactory results with Eurocode 2 presenting slightly higher performance.
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