RESUMO A aplicação de materiais álcali-ativados em obras de engenharia ainda é limitada, principalmente, porque alguns precursores necessitam de cura térmica para que ocorra a ativação alcalina. Nessa perspectiva, o objetivo desta pesquisa é avaliar o comportamento no estado fresco e no estado endurecido de argamassas álcali-ativadas à base de cinza volante, curadas em temperatura ambiente. Para a produção das argamassas, utilizou-se um ativador alcalino composto de silicato e hidróxido de sódio, variou-se a relação entre solução ativadora e precursor (s/p) em 0,45, 0,55 e 0,65. Os produtos da reação de álcali-ativação foram identificados por espectroscopia de infravermelho (FTIR) e análises térmicas. No estado fresco foram executados os ensaios Flow Table e Squeeze Flow e no estado endurecido foram realizados ensaios de resistência à compressão e resistência à tração na flexão. Os resultados indicam a formação do gel N-A-S-H (aluminossilicato de sódio hidratado) como principal produto de reação. A trabalhabilidade e a resistência mecânica das argamassas álcali-ativadas foram influenciadas pela quantidade de solução alcalina e água adicional. Os resultados foram satisfatórios, registrou-se resistências à tração entre 5,4 MPa e 11,1 MPa e resistências à compressão entre 11,1 MPa e 33,3 MPa, aos 28 dias.

ABSTRACT Knowledge and technology in alkali-activated materials has grown in recent years. However, the application in engineering works is still limited, mainly because some precursors require thermal curing for alkaline activation to occur. In this perspective, the objective of this research is to evaluate the behavior in the fresh state and in the hardened state of alkali-activated mortars based on fly ash, cured at ambient temperature. For the production of mortars, an alkaline activator composed of silicate and sodium hydroxide was used, the ratio between activator solution and precursor (s/p) was varied in 0.45, 0.55 and 0.65. Additionally, a conventional mortar was produced for comparison. The products of the alkali-activation reaction were identified by infrared spectroscopy (FTIR) and thermal analysis. In the fresh state, the Flow Table and Squeeze Flow tests were carried out and in the hardened state, tests of compressive strength and tensile strength in bending were carried out. The results indicate the formation of N-A-S-H gel (hydrated sodium aluminum silicate) as the main reaction product. The workability and mechanical strength of alkali-activated mortars were influenced by the amount of alkaline solution and additional water. The results were satisfactory, with tensile strengths between 5.4 MPa and 11.1 MPa and compressive strengths between 11.1 MPa and 33.3 MPa, at 28 days. These values increased as the s/p ratio increased and the additional water decreased. The conventional mortar presented flexural tensile strength of 3.3 MPa and compressive strength of 18.5 MPa. Therefore, alkali-activated mortars based on fly ash have characteristics and properties that enable their application in loco in civil construction.

RESUMO Comparou-se o efeito da absorção sistêmica do colírio de diclofenaco de sódio 0,1% (DS) em relação ao de cetorolaco de trometamina 0,5% (CT) em coelhas da raça Nova Zelândia, tratadas nos dois olhos, três vezes ao dia, por 90 dias. As coelhas foram separadas em três grupos de seis animais (n=18): grupo CT, grupo DS e grupo controle (Co), no qual foi instilada solução fisiológica (NaCl 0,9%). Os consumos de água e ração foram mensurados diariamente, os exames clínicos foram realizados semanalmente e o sangue foi coletado a cada 30 dias para realização de exames laboratoriais. O plasma foi analisado para detectar a presença de CT e DS por extração em fase sólida (SPE) associada à espectrometria de massas (MS). A absorção sistêmica desses fármacos foi confirmada por SPE-MS, permitindo sua separação e identificação no plasma. Ao final do tratamento, os animais foram eutanasiados e necropsiados, e não foram encontradas alterações macroscópicas ou microscópicas. Essa observação confirmou os resultados laboratoriais, que estavam dentro dos padrões de referência para a espécie. De acordo com os resultados obtidos, pode-se concluir que o tratamento com colírio contendo KT e DS, por 90 dias, em coelhos saudáveis, não causa efeitos adversos sistêmicos.

ABSTRACT The effect of the systemic absorption of 0.1% diclofenac sodium (DS) eyedrop was compared to that of 0.5% ketorolac tromethamine (KT) in female New Zealand white rabbits treated on both eyes three times a day for 90 days. The rabbits were divided in three groups of six animals (n= 18): KT group, DS group, and control (Co) group, in which saline (0.9% NaCl) solution was instilled. Water and food consumption were measured daily, clinical examination was performed weekly, and blood samples were collected every 30 days for laboratory examination. The plasma was analyzed for the presence of KT and DS by solid-phase extraction (SPE) associated with mass spectrometry (MS). Systemic absorption of these drugs was confirmed by SPE-MS, allowing their separation and identification in the plasma. At the end of the treatment, the animals were euthanized and necropsied, and no macroscopic or microscopic changes were found. This observation confirmed the laboratory results, which were within normal reference standards for the species. According to the results obtained, it can be concluded that treatment with eyedrops containing KT and DS for 90 days in healthy rabbits does not cause adverse systemic effects.

Special attention has emerged towards biomass smoke-induced chronic obstructive pulmonary disease (COPD), providing new knowledge for prevention and therapeutic approach of non-smoker COPD patients. However, the understanding of biomass smoke COPD is still limited and somewhat controversial. The aim of the present study was to compare COPD exclusively caused by tobacco smoking with COPD exclusively caused by environmental or occupational exposures. For this cross-sectional study, COPD patients were recruited from outpatient clinics and formed two groups: non-smoker COPD group (n=16) with exposure to biomass smoke who did not smoke cigarette and tobacco smoker COPD group (n=15) with people who did not report biomass smoke exposure. Subjects underwent pulmonary function tests, thoracic high-resolution computed tomography, 6-min walk test, and sputum induction. The non-smoker COPD group had biomass smoke exposure of 133.3±86 hour-years. The tobacco COPD group smoked 48.5±27.4 pack-years. Women were 62.5 and 66.7%, respectively, of non-smokers and smokers. The non-smoker COPD group showed higher prevalence of dyspnea, lower arterial oxygen tension (PaO2), and lower arterial oxygen saturation (SaO2%) with similar spirometry results, lung volumes, and diffusion capacity. Regarding inflammatory biomarkers, differences were detected in sputum number of lymphomononuclear cells and in sputum concentrations of interleukin (IL)-6 and IL-8 with higher values in the smoker group. Emphysema was more prevalent in the tobacco smoker group, which also showed higher relative bronchial wall thickness and lower lung density by quantitative analysis. Biomass smoke induced more hypoxemia compared to tobacco in COPD patients with similar severity.

Additives have been used to improve quality diet and animal development. The objective was to assess the effects of probiotic or phytase supplementation on apparent digestibility of nutrients in 24 Mangalarga Marchador foals (16 males, 8 females), aged 241.6 ± 23.2 days (mean ± SD/SEM), and weighing 216.7 ± 27.8 kg. The study lasted 28 days, the first 23 for diet and handling adaptation, and the last five days for fecal collection. The basal diet consisted of Cynodon pasture and pelleted concentrate (1.2 kg/100 kg body weight), as well as water and mineral salt ad libitum. There were four treatments: basal diet (T1); basal diet + 5 g/day of 10(9) CFU/g of s. cerevisiae (T2); basal diet + 2 g/day of 10(8)CFU/g of bacteria B. bifidum, E. faecium, L. acidophilus, L. plantarum and 10(5) CFU/g of s. cerevisiae (T3); and basal diet + 1250 FTU/day of phytase (T4). The DM intake was estimated with an external marker (LIPE©) associated with cecal in situ digestibility of DM. All foals were randomized by replicate using a 4 x 2 factorial, and results were compared using student's t-test (p<0.05). Group T3 showed better digestibility of crude protein, total minerals, calcium and phosphorus; whereas T2 had better digestibility of hemicellulose and calcium. Group T4 had better digestibility of neutral detergent fiber and intermediary values of minerals digestibility. Probiotics can be used as a nutritional strategy to improve the digestibility of a foal's diet, particularly when live bacteria and yeast culture are used. A phytase dose of 205 FTU/kg DM in the basal diet improved fiber digestibility, indicating its potential in equine nutrition.

El uso de aditivos se ha desarrollado mucho actualmente, con el fin de mejorar el aprovechamiento de la dieta. El presente trabajo se realizó con el objetivo de evaluar los efectos de la suplementación con probióticos o fitasa sobre la digestibilidad aparente (DA) de los nutrientes en 24 potros (16 machos y 8 hembras) Mangalarga Marchador con 241,6 ± 23,2 días de edad y 216,7 ± 27,8 kg de peso vivo (PV). El experimento tuvo duración de 28 días (23 para la adaptación y cinco para la recogida de muestras de heces) y la dieta basal se compuso de pasto de Cynodon y pienso comercial (1,2 kg /100 kg PV), además de agua y sal mineralizada ad libitum. Los tratamientos fueron: dieta basal (T1); dieta basal + 5 g/día de 10(9)UFC/g de levadura S. cerevisiae (T2); dieta basal + 2 g/día de 10(8) UFC/g de bacterias B. bifidum, E. faecium, L. acidophilus, L. plantarum y 10(5) UFC/ g de levadura S. cerevisiae (T3); y dieta basal + 1250 FTU (unidades de fitasa)/dia (T4). La estimación del consumo se realizó utilizando el indicador externo LIPE® y la técnica de digestibilidad in situ. El diseño estadístico fue enteramente al azar, en esquema factorial 4 x 2, y las medias fueron comparadas por el test t de student (p<0,05). El grupo T3 tuvo mejor DA de la proteína bruta, cenizas, calcio y fósforo. El grupo T2 tuvo mejor DA de la hemicelulosa y calcio. El grupo T4 tuvo mejor DA de la fibra neutrodetergente y fue intermedio en DA de los minerales. Los resultados indicaron que los probióticos pueden ser una estrategia para la mejora del aprovechamiento de la dieta de potros, sobre todo cuando están compuestos por bacterias y levaduras vivas. La fitasa mejoró el aprovechamiento de la fibra cuando se administró en dosis de 205 FTU/kg de la dieta total, demostrando su potencial para la utilización en la nutrición equina.