Universidade Federal de Santa Maria

About: Universidade Federal de Santa Maria is a education organization based out in Santa Maria, Brazil. It is known for research contribution in the topics: Population & Context (language use). The organization has 21178 authors who have published 35632 publications receiving 371665 citations.

Single and binary adsorption of sulfonamide antibiotics onto iron-modified clay: linear and nonlinear isotherms, kinetics, thermodynamics, and mechanistic studies

Abstract: Iron-modified raw kaolinite clay (Fe-MC) was synthesized by co-precipitation method, characterized, and then applied as a low-cost adsorbent to sequester sulfachloropyridazine (SCP) and sulfadimethoxine (SDM), emergent water contaminants, from aqueous media by batch equilibration at circumneutral pH. The adsorption rate was kinetically described by the pseudo-second-order model. Equilibrium monocomponent sorption data were fitted to three two-parameter linear and nonlinear isotherm models. The data were best described by Temkin and Langmuir nonlinear equations. Linearization of adsorption isotherms is demonstrated to be an unsuitable analytical tool for predicting adsorption isotherms. The Langmuir monolayer maximum adsorption capacities were 4.561 and 1.789 mg/g for SCP and SDM, respectively. The binary adsorption study showed an antagonistic adsorption process of SCP (Rq, SCP= 0.625) in the presence of SDM (Rq, SDM = 1.032). The thermodynamic parameters, namely enthalpy (ΔH), Gibbs free energy (ΔG), entropy (ΔS), Arrhenius activation energy (ΔEa), and sticking probability (S*), indicated that the processes are spontaneous, exothermic, and physical in nature. The adsorption process was attributed to hydrogen bonding and negative charge-assisted H-bonding (CAHB). Using the Langmuir isotherm, the amount of Fe-MC required for a given volume of effluent of known contaminant concentration could be predicted.

Piscicultura continental no Rio Grande do Sul: situação atual, problemas e perspectivas para o futuro

Abstract: This review deals with freshwater fish culture in Rio Grande do Sul State, southern Brazil, and analyzes production and problems of this activity in the last years. This State contributes with a good percentage of Brazilian freshwater fish culture, but its production has been stagnated in the last years. Production is based essentially on exotics fish species (mainly carps). Fish sales are concentrated in the Easter period, and sanitary inspection is still reduced. Fish farmers are making cooperatives in the central region of Rio Grande do Sul. The publishing of books of native species and the freshwater fisheries stagnation in the last years may stimulate the raise of native species, and some are suggested in this review. The culture of native species to be sold as ornamental fishes is still a future option for fish farmers of this State.

Swimming training induces liver mitochondrial adaptations to oxidative stress in rats submitted to repeated exhaustive swimming bouts.

Abstract: Background and Aims Although acute exhaustive exercise is known to increase liver reactive oxygen species (ROS) production and aerobic training has shown to improve the antioxidant status in the liver, little is known about mitochondria adaptations to aerobic training. The main objective of this study was to investigate the effects of the aerobic training on oxidative stress markers and antioxidant defense in liver mitochondria both after training and in response to three repeated exhaustive swimming bouts.

Antigenic relationships between Bovine viral diarrhea virus 1 and 2 and HoBi virus: possible impacts on diagnosis and control

Abstract: The emergence of a newly recognized group of pestiviruses in cattle, the HoBi-like viruses, requires an evaluation of the available diagnostic tools and vaccines. The present study compared antigenic characteristics of Bovine viral diarrhea virus 1 and 2 (BVDV-1, -2) strains and HoBi virus. This comparison was based on detection of HoBi virus and antibodies against it by commercial enzyme-linked immunosorbent assays (ELISAs) and the level of cross-neutralizing antibodies present in sera from animals vaccinated with BVDV. Reactivity with a panel of monoclonal antibodies (mAbs) revealed greater cross-reactivity between BVDV species (BVDV-1, -2) and HoBi epitopes within E(rns) and NS2/3 proteins than between epitopes located in the E2 glycoprotein. The results suggest that a diagnostic test designed to detect both BVDV species and HoBi could be based on E(rns) or NS2/3 epitopes, while variation among E2 epitopes could be exploited in tests for differentiation of pestivirus species. The threshold of detection of HoBi virus by an antigen-capture ELISA kit based on detection of E(rns) was statistically similar to that for BVDV. In contrast, 2 commercial ELISA kits designed to detect antibodies against BVDV missed 22.2% and 77.7%, respectively, of serum samples harboring HoBi virus-neutralizing antibodies. In addition, sera of calves vaccinated with BVDV-1 and -2 presented low neutralizing activity against HoBi virus. The results demonstrate that in spite of antigenic similarities, HoBi virus is antigenically distinct from both BVDV species. Detection and control of HoBi virus infections in cattle would thus require the development of new diagnostic reagents and reformulation of current vaccines.