Resumen: El objetivo de este trabajo es investigar el comportamiento del estado fresco y endurecido de las pastas cementosas activadas con álcali obtenidas de la mezcla de cenizas de fondo/escoria BOF y cenizas volantes/escoria BOF. Para el propósito, se evaluaron las propiedades en el fresco y estado endurecido. Se produjeron diez pastas en dos sistemas separados, cuyas proporciones entre cenizas y escoria BOF fueron 100: 0, 75:25, 50:50, 25:75 y 0: 100 (cenizas volantes o cenizas de fondo: escoria BOF). En general, la adición de escoria de acero BOF actúa acelerando los tiempos de configuración, a temperatura ambiente de curado. Además, las curvas tensión-deformación demostraron que las cenizas pesadas y la escoria de acero BOF favorecen el comportamiento dúctil en tensión axial. Además, la adición de escoria BOF puede influir en las propiedades en estado fresco y endurecido. Por tanto, es factible utilizar escoria de acero combinada con ceniza de carbón en mezclas binarias alcalinas activadas.

Abstract: The focus of this paper is to investigate the behavior of the fresh and hardened state of alkali-activated cementitious pastes obtained from the mixture of bottom ash/BOF slag and fly ash/BOF slag. For this purpose, the properties in the fresh and hardened state were evaluated. Ten pastes were produced in two separate systems, whose proportions between ashes and BOF slag were 100:0, 75:25, 50:50, 25:75, and 0:100 (fly ash or bottom ash: BOF slag). In general, the addition of BOF steel slag works by accelerating the setting times, at room temperature curing. In addition, the stress-strain curves demonstrated that heavy ash and BOF steel slag favor the ductile behavior under axial stress. Furthermore, the addition of BOF slag can influence the properties in the fresh and hardened state. Therefore, it is feasible to use steel slag combined with coal ash in alkaline activated binary mixtures.

Resumo Este trabalho objetivou obter proteases aspárticas de interesse industrial e biotecnológico a partir do estômago do peixe xaréu (Caranx hippos). Para isso, foi obtido um extrato bruto do estômago, o qual foi submetido a uma purificação parcial por salting-out onde se obteve o extrato enzimático (EE). As proteases do EE foram caracterizadas físico-quimicamente e através de zimograma. Além disso, o efeito de agentes químicos sobre sua atividade também foi avaliado. Através de salting-out foi possível obter uma purificação de 1,6 vezes com rendimento de 49,4%. Foram observadas duas proteases ácidas presentes no EE através de zimograma. A temperatura ótima e a estabilidade térmica para as proteases ácidas do EE foram de 55 ºC e 45 °C, respectivamente. O pH ótimo e a estabilidade ao pH encontrados para estas enzimas foram o pH 1,5 e 7,0, respectivamente. Observou-se a inibição total da atividade proteolítica ácida do EE na presença de pepstatina A. O ditiotreitol (DTT) e o Ca2+ não promoveram efeito significativo na atividade enzimática. Na presença de metais pesados, como Al3+, Cd2+ e Hg2+, o EE manteve mais de 70% de atividade enzimática do EE. Os resultados mostram que é possível obter, a partir do estômago de C. hippos, proteases aspárticas com alta atividade proteolítica e características que demonstram potencial para aplicações industriais e biotecnológicas.

Abstract This work aimed to obtain aspartic proteases of industrial and biotechnological interest from the stomach of the crevalle jack fish (Caranx hippos). In order to do so, a crude extract (CE) of the stomach was obtained and subjected to a partial purification by salting-out, which resulted in the enzyme extract (EE) obtainment. EE proteases were characterized physicochemically and by means of zymogram. In addition, the effect of chemical agents on their activity was also assessed. By means of salting-out it was possible to obtain a purification of 1.6 times with a yield of 49.4%. Two acid proteases present in the EE were observed in zymogram. The optimum temperature and thermal stability for EE acidic proteases were 55 ºC and 45 °C, respectively. The optimum pH and pH stability found for these enzymes were pH 1.5 and 7.0, respectively. Total inhibition of EE acid proteolytic activity was observed in the presence of pepstatin A. dithiothreitol (DTT) and Ca2+ did not promote a significant effect on enzyme activity. In the presence of heavy metals, such as Al3+, Cd2+ and Hg2+, EE acidic proteases showed more than 70% of their enzymatic activity. The results show that it is possible to obtain, from the stomach of C. hippos, aspartic proteases with high proteolytic activity and characteristics that demonstrate potential for industrial and biotechnological applications.

Resumo As vísceras e outros resíduos do processamento de peixes são geralmente descartados pela indústria pesqueira. Esses resíduos podem ser uma fonte de enzimas digestivas com potencial industrial e biotecnológico. Neste estudo, objetivamos a extração, caracterização e aplicação de proteases aspárticas do estômago de Carangoides bartholomaei (Cuvier, 1833). Um extrato bruto do estômago foi obtido e submetido a um processo de purificação parcial, que obteve um Extrato Purificado (EP) com uma atividade proteolítica específica de 54,0 U⋅mg-1. Foi obtida uma purificação de 1,9 vezes e um rendimento de 41%. O EP apresenta duas isoformas de proteases ácidas e atividade proteolítica máxima a 45 °C e pH 2,0. A atividade proteolítica do EP foi estável na faixa de pH de 1,5 a 7,0 e temperatura de 25 °C a 50 °C. O EP manteve 35% de sua atividade proteolítica na presença de NaCl a 15% (m/v), mas foi totalmente inibida pela pepstatina A. As proteases ácidas do EP apresentaram alta atividade na presença de metais pesados como o Cd2+, Hg2+, Pb2+, Al3+ e Cu2+. A utilização de EP como aditivo enzimático na extração de colágeno a partir de escamas de tilápia do Nilo dobrou o rendimento do processo. Os resultados indicam um potencial dessas proteases para aplicações industriais e biotecnológicas

Abstract The viscera and other residues from fish processing are commonly discarded by the fishing industry. These by-products can be a source of digestive enzymes with industrial and biotechnological potential. In this study, we aimed at the extraction, characterization, and application of acidic proteases from the stomach of Carangoides bartholomaei (Cuvier, 1833). A crude extract from the stomachs was obtained and submitted to a partial purification process by salting-out, which obtained a Purified Extract (PE) with a specific proteolytic activity of 54.0 U⋅mg-1. A purification of 1.9 fold and a yield of 41% were obtained. The PE presents two isoforms of acidic proteases and a maximum proteolytic activity at 45 °C and pH 2.0. The PE acidic proteolytic activity was stable in the pH range of 1.5 to 7.0 and temperature from 25 °C to 50 °C. Purified Extract kept 35% of its proteolytic activity at the presence of NaCl 15% (m/v) but was totally inhibited by pepstatin A. Purified Extract aspartic proteases presented high activity in the presence of heavy metals such as Cd2+, Hg2+, Pb2+, Al3+, and Cu2+. The utilization of PE as an enzymatic addictive in the collagen extraction from Nile tilapia scales has doubled the process yield. The results indicate the potential of these aspartic proteases for industrial and biotechnological applications.

Abstract The capability to recycle waste materials, such as steel slag, has appealed to the construction industry, as the cement industry faces a major challenge to reduce carbon dioxide (CO2) emissions into the atmosphere. This paper investigated the obtainment of cement pastes with Kanbara reactor desulfurization waste slag (KR slag) through alkaline activation using silicate and sodium hydroxide solutions. The mixtures were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), compressive strength, and physical property tests. The FTIR, XRD, and TGA results pointed to chemical activation, forming C-S-H and C-(A)-S-H gels. The formation of these compounds indicated the possibility of using KR slag in cementitious composites for civil construction.

Abstract Composite materials are employed as an alternative of conventional materials due their attractive properties, such as, environmental resistance and high strength-to-weight ratio. However, a limitation to the application of the composites is the low resistance to high temperatures, due their polymeric matrix. Alternatively, geopolymers are inorganic polymers used mainly instead Ordinary Portland Cement (OPC) in civil engineering. They combine good mechanical properties, corrosion resistance and thermal stability, allowing the use as a thermal barrier. This work regards the combined application of composites and geopolymers through adhesive bonding. The main objective is to evaluate the effect of adhesive type and surface treatment on the adhesion between geopolymer and composite pultruded substrates. Pull off tests were carried out in composite-adhesive-geopolymer sandwich specimens. Different surface treatments were examined: unidirectional abrasion and bidirectional abrasion. Specimens were bonded either with an epoxy or a polyurethane adhesive. The influence of the geopolymer manufacturing process on the performance of the structure was also observed.

The use of radiotracers allows the understanding of the bioavailability process, biodistribution, and kinetics of any molecule labelled with an isotope, which does not alter the molecule's biological properties. In this work, technetium-99m and iodine-125 were chosen as radiotracers for biodistribution studies in mice using bee (Apis mellifera) venom and a toxin (PnTX2-6) from the Brazilian "armed" spider (Phoneutria nigriventer) venom. Incorporated radioactivity was measured in the blood, brain, heart, lung, liver, kidney, adrenal gland, spleen, stomach, testicle, intestine, muscle, and thyroid gland. Results provided the blood kinetic parameter, and different organs distribution rates.

Ionizing radiation can change the molecular structure and affect the biological properties of biomolecules. This has been employed to attenuate animal toxins. Crotamine is a strongly basic polypeptide (pI 10.3) from Crotalus durissus terrificus venom composed of 42 amino acid residues. It induces skeletal muscle spasms leading to a spastic paralysis of hind limbs in mice. The objective of the present study was to carry out a biochemical study and a toxic activity assay on native and irradiated crotamine. Crotamine was purified from C.d. terrificus venom by Sephadex G-100 gel filtration followed by ion-exchange chromatography, and irradiated at 2 mg/ml in 0.15 M NaCl with 2.0 kGy gamma radiation emitted by a 60Co source. The native and irradiated toxins were evaluated in terms of structure and toxic activity (LD50). Irradiation did not change the protein concentration, the electrophoretic profile or the primary structure of the protein although differences were shown by spectroscopic techniques. Gamma radiation reduced crotamine toxicity by 48.3%, but did not eliminate it.

The effect of pheromones and their chemical analogues in honeybee alarm behaviors was studied in observation boxes. Defensive behaviors, as follows: a) attraction to scent source, b) elevation of wings in "V", c) abdomen elevation, d) abdomen elevation and pumping and e) first leg pair elevation had been temporarily registered when the following compounds were presented: isoamyl alcohol, octyl alcohol, benzyl alcohol, n-butyl acetate, n-octyl acetate, isopentyl acetate, benzyl acetate and 2-heptanone. The results were as follows: 1. the bees elicited some characteristic behaviors when chemical alarm messages were presented, 2. agression (stinging) was not completed with any compound tested, probably because there was not a target (visual stimulus), 3. in all situations the attraction to scent source was low, 4. all the behaviors were elicited in a temporarily different way, 5. the compounds that elicited stronger responses and a greater number of the investigated behaviors were: isopentyl acetate, 2-heptanone, octyl acetate and n-octyl alcohol. In all situations, the first behavior response (and the most intense one) was the elevation and pumping the abdomen. This suggests that the chemical message was promptly recognized and then transmitted to each worker. So, the results obtained in the present work, suggest that chemical alarm messages may be recognized by different mechanisms of neural integration.

De janeiro a dezembro-1986, nasceram 120 crianças com peso ao nascimento inferior a 1500 gramas. Dessas, 85 foram escolhidas para estudo por apresentarem avaliação ultrassonográfica de crânio e/ou estudo necroscópico. A mortalidade do grupo de estudo foi da 70%, porém a mortalidade geral no período foi de 52,5%. A avaliação ultrassonográfica foi realizada em 41 crianças. A incidência de hemoragia peri-intraventricular (HPIV) foi de 42,3%. Vinte e três crianças (63,8%) apresentaram HPIV grau II ou III; 10 apresentaram HPIV grau I (27,7%) e apenas 3 (8,3%) tinham o grau IV. Treze crianças tinham realizado ultrassonografia de crânio e exame necroscópico. Houve concordância total entre as duas avaliações em 9 (69%), enquanto 2 casos (16%) apresentavam concordância parcial, pois o diagnóstico dos graus de HPIV foram divergentes. Apenas 2 casos apresentavam discordância entre as avaliações de ultrassom e necrópsia. Em ambos a avaliação ultrassonográfica inicial mostrou ausência de hemorragia intracraniana e a necrópsia, HPIV. Entretanto, o óbito ocorreu 20 e 53 dias, respectivamente, após a avaliação sonográfica. Concluimos que a incidência de HPIV foi comparável à referida na literatura e que o exame ultrassonográfico de crânio é bastante confiável para o seu diagnóstico.

From January to December 1986, 120 preterm infants were born with birth-weight under 1500 gm. Eighty-five infants were included in the study group either because they had a cranial sonographic evaluation or a necropsy. The mortality rate was 70% for the study group, but was 52.5% for the whole period. The sonographic examination was performed in 41 infants. The incidence of periventricular-intraventricular hemorrhage (PIVH) was 42.3%. Twenty-three cases had PIVH grade II (63.8%), 10 grade I (27.7%), and 3 (8.3%) grade IV Thirteen infants had sonographic and necroscopic examinations. We observed a total agreement between sonographic and necroscopic diagnosis in 9 cases (69%). Two cases were classified as partial agreement as they differed only in the grading of PIVH, whereas in two cases there was a failse negative diagnosis in the ultrasound examination. The interval between the examinations in these two false negative cases was 53 and 20 days, respectively. We conclude that the incidence of PIVH found in our study is comparable to that of the literature and that cranial ultrasonography is a sensitive neuroimage tecnique for the diagnosis of PIVH in the newborn preterm infant.