The present work aims to evaluate the manufacturing processes of free-standing graphene oxide (GO)/reduced graphene oxide(rGO)/carbon nanotube (MWCNT) papers-like and the effect on electrical conductivities after annealing treatment. The pure GO and the hybrid papers were obtained by vacuum filtration and submitted to mild thermal annealing at 400 °C under an argon atmosphere. Analyses comparing the carbon paper-like materials before and after thermal treatment were done by thermogravimetric analysis (TGA), Raman spectroscopy, scanning electron microscopy (SEM), and electrical conductivity measurements. The characterization results show the annealing process effect on the morphology of paper materials. The GO papers and the hybrid (GO/rGO/MWCNT) exhibited good free-standing structure properties. The SEM results suggest the formation of gas void due to the thermal treatment. TGA and Raman results showed the thermal reduction and restoration of the carbon sp2 network of the graphene oxide induced by thermal treatment. The thermal treatment was responsible for changing the almost insulator characteristic of free-standing pure GO paper, achieving an electrical conductivity of 752 S/m, and improving 45% of the free-standing hybrid carbon nanomaterials papers (GO/rGO/MWCNT) electrical conductivity, achieving the value of 1020 S/m.

Abstract In this paper the production and characterization of compacted graphite iron alloys in ten chemical compositions is presented. The specimens were obtained through a foundry process performed by a gating system model developed in order to allow the incorporation of silicon, copper and tin. Hardness and tensile tests were performed, as well as microstructural evaluation. Additionally, the results related to the experimental investigation were compared to those obtained from a finite element method analysis. The results showed a correlation between the addition of silicon and the increase of ferrite and graphite count per mm2. Regarding copper and tin additions, the percentage increase of pearlite was associated with the reduction of graphite average size. Changes in chemical composition led to different values of ultimate tensile strength, yield strength and hardness, whose magnitude was mainly related to the amount of ferrite. Computer simulation was considered efficient in predicting these results.

Resumen: Las enfermedades respiratorias de los terneros son un problema sanitario importante debido a que cursan con altas tasas de morbilidad y mortalidad, originando grandes pérdidas económicas. El objetivo de este estudio fue determinar la presencia de anticuerpos séricos frente a los principales agentes etiológicos virales relacionados con la bronconeumonía en bovinos (virus de la diarrea viral bovina, herpesvirus bovino tipo-1 y virus respiratorio sincitial bovino), evaluando la asociación entre la presencia de anticuerpos y las manifestaciones clínicas. Se estudiaron 63 terneros pertenecientes a dos rebaños del estado de Sao Paulo (Brasil). Los animales fueron divididos en dos grupos: animales sanos y enfermos con sintomatología respiratoria después del examen físico. Se extrajo sangre para la posterior detección de anticuerpos en suero por neutralización viral y se estudió la asociación entre los signos clínicos y los hallazgos serológicos. Los anticuerpos frente al virus de la diarrea viral bovina, herpesvirus bovino tipo-1 y virus respiratorio sincitial bovino se detectaron respectivamente en el 57,10%, el 66,70% y el 93,70% de las muestras. Se observó una mayor frecuencia de anticuerpos contra el virus de la diarrea viral bovina en animales con exudado nasal seroso / mucoso (P = 0,01). Los animales deshidratados (P = 0,008) y aquellos con temperatura rectal por encima de 39,5 ºC (P = 0,03) presentaron con mayor frecuencia anticuerpos frente al virus respiratorio sincitial bovino. El presente trabajo presentó resultados de seropositividad más elevados a los encontrados en otros estudios realizados en granjas con un sistema de manejo extensivo, confirmando la importancia del manejo en la transmisión de estos microorganismos.

Summary: Respiratory diseases are a major health problem due to the high morbidity and mortality rates, with great economic losses. The aim of this study was to determine the frequency of antibodies against the main viral etiological agents related to bronchopneumonia in cattle (bovine viral diarrhea virus, bovine herpesvirus type-1 and bovine respiratory syncytial virus), searching for associations between these agents and the clinical signs observed. We studied 63 calves from two herds from São Paulo, Brazil. After physical examination, the calves were divided into healthy calves and calves with respiratory disease. Serum was obtained for subsequent detection of antibodies by viral neutralization. The association between clinical signs and serological findings was studied. Antibodies against bovine viral diarrhea virus, bovine herpesvirus type-1 and bovine respiratory syncytial virus were detected in 57.10%, 66.70% and 93.70% of the samples. A higher frequency of antibodies against bovine viral diarrhea virus was observed in animals with serous / mucous nasal discharge (P = 0.01). The dehydrated animals (P = 0.008) and those with a rectal temperature above 39.5 ºC (P = 0.03) presented a higher frequency of antibodies against the bovine respiratory syncytial virus. The present work presented results superior to those found in studies in farms with extensive system, confirming the importance of management in the transmission of microorganisms.

Saponins, molecules classified as triterpenic or steroidal glycosides, are metabolites distributed in all the plant kingdom that can be used for the production of foods, cosmetics, and pharmaceuticals, as well as in soil bioremediation. Saponins are normally extracted from natural resources with water, ethanol and/or methanol, and then concentrated by liquid-liquid partitioning with n-butanol. An alternative concentration method is with a foam column, by which the saponins can be concentrated via preferential adsorption at a gas-liquid interface. Therefore, the objective of this work was the use of a foam column for the concentration of saponins from juá and sisal, evaluating parameters such as: initial working volume in the column, saponin concentration in the extracts from juá and sisal, air flow rate, pH, Raschig rings loading and operation time. When a gradient air flow rate and 25 g of Raschig rings were used, 82.6% of the jua saponins loaded onto the system were recovered in a 3.46-fold concentrated solution after 9 h of operation. Regarding sisal saponins, a concentration factor of 1.98 was observed with 90.5% of saponin recovery during 4.5 h of operation.

Conjugated linoleic acid (CLA) refers to a family of polyunsaturated fatty acids, being represented by a group of isomers of linoleic acid called conjugated for having a double bound after a simple bound. Among its isomers, trans-10,cis-12 and cis-9, cis-12 CLA stand out. These isomers can lead to different effects on the body: anticarcinogenic, antidiabetogenic, antiatherogenesis and positive body composition alteration. The objective of this review is to describe their mechanisms of action, effects on body composition, on plasmatic lipoproteins and supplementation. Studies about CLA supplementation show its capacity of reducing fat percentage, body mass and of promoting an improvement in lipid metabolism. One of the adverse effects attributed to one of the isomers is insulin resistance by body fat redistribution. Limitations in the scientific models used in CLA researches make impossible to draw conclusions about the action of this fatty acid on human metabolism.

El ácido linoleico conjugado (CLA) es un ácido graso que pertenece al grupo de los ácidos grasos poliinsaturados, representado por el conjunto de isómeros del ácido linoleico, que son denominados conjugados porque poseen una doble conexión tras una conexión simple. De entre sus isómeros se distinguen el trans-10,cis-12 y cis-9, cis-12 CLA. Estos isómeros son capaces de promover efectos distintos en el organismo: anticarcinogénesis, antidiabetogénesis, antiaterogénesis y cambios de composición corporal. El objetivo de esta revisión es describir sus mecanismos de acción, los efectos en las lipoproteínas plasmáticas, en la composición corporal y la suplementación. Los estudios acerca de la suplementación del CLA demuestran su capacidad de reducir el porcentaje de grasa, el peso corporal, y de mejorar el metabolismo lipídico. Sin embargo, unos de los efectos contrarios relacionados a uno de sus isómeros es la resistencia a la insulina a través de la redistribución de grasa corporal. Las limitaciones en los modelos científicos adoptados en investigaciones acerca del CLA nos quitan la posibilidad de hacer conclusiones cuanto a la acción de este ácido graso en el metabolismo humano.