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Araioses, Brazil

Dos Santos R.C.,Federal University of Piaui | Amorim A.D.G.N.,Federal University of Piaui | Thomasi S.S.,Federal University of Sao Carlos | Figueiredo F.C.,Federal University of Piaui | And 6 more authors.
Fuel | Year: 2015

An electrochemical method was applied in order to obtain a new antioxidant for soy biodiesel conservation, from the technical CNSL (tCNSL). The electrochemical modification occurred in an electrolytic tank under controlled conditions, including the voltage, electrical current and tCNSL flow. Physico-chemical analysis and Fourier Transform Infrared (FTIR) were carried out on tCNSL and eCNSL, while Gas Chromatography coupled to Mass Spectrometry (CG-MS) and Nuclear Magnetic Resonance (NMR) was carried out only on eCNSL to characterize the occured transformations after the electrolysis process. The Rancimat results showed that when eCNSL was added to the soy biodiesel, it was able to increased it is oxidative stability and the Induction Period (IP = 7.31 ± 0.20) values were higher than that required by ANP (Agency of Petroleum, Natural Gas and Biofuels). The electrolytic tests results combined with GC-MS displayed a significant decrease in the cardanol percentage which can promote the formation of dimers or oligomers that may be responsible for the increased antioxidant activity of the eCNSL. Therefore, the electrolysis process resulted in an effective biofuel antioxidant that presents interesting commercial advantages. ©2014 Published by Elsevier Ltd. Source


dos Santos E.P.,University of Brasilia | dos Santos E.P.,Federal Institute of Piaui | Gadelha A.B.,University of Brasilia | Safons M.P.,University of Brasilia | And 3 more authors.
Archives of Gerontology and Geriatrics | Year: 2014

The purpose of this study was to examine the association between sarcopenia and sarcopenic obesity (SO) with cardiometabolic risk factors in postmenopausal women. 149 volunteers (67.17±6.12 years) underwent body composition assessment using dual energy X-ray absorptiometry (DXA) and had analyzed blood samples collected for lipid profile, glucose metabolism and C-reactive protein (CRP). Sarcopenia was defined as an appendicular fat-free mass (AFFM) divided by height squared ≤5.45kg/m2 while SO was classified based on the residuals of a regression. Waist circumference (WC) and arterial blood pressure were also measured. Student's t-tests and correlations were used for analyses. Prevalence of sarcopenia and SO were respectively 16.8 and 21.5%. WC was significantly correlated with all the examined risk factors. AFFM relative to height squared was positively correlated with systolic blood pressure (SBP) and diastolic blood pressure (DBP), CRP, insulinaemia, HOMA score, and those classified as sarcopenic presented lower HOMA score when compared to nonsarcopenic. Regarding SO, although volunteers classified presented significantly higher fat mass (FM) and lower AFFM, it was not observed association with the examined risk factors. These findings support the association between WC and cardiometabolic risk factors in older women. In contrast, the approaches used to define sarcopenia and SO are not associated with cardiometabolic impairments. © 2014 Elsevier Ireland Ltd. Source


Da Ponte D.F.,Federal Institute of Piaui | Da Rocha C.A.F.,Federal University of Santa Catarina | Hizume D.C.,Santa Catarina State University | Moraes R.,Federal University of Santa Catarina
IEEE Transactions on Instrumentation and Measurement | Year: 2014

Lung sounds recorded on the chest are attenuated by the thorax and thorax-microphone interface. In order to recover waveforms similar to the ones generated within the lungs, this paper equalizes crackle sounds recorded on the chest. From an experiment in which eight subjects (seven men) took part, an estimation of the channel (thorax and thorax-microphone interface) attenuation was obtained to design the equalizer. For that, multiple tones between 100 and 1200 Hz were applied to each subjects' mouth where they were acquired by an electret microphone. These tones were also recorded on the chest using another electret microphone housed into an acoustic coupler. The attenuation of each tone was calculated by the power ratio between the one measured on the chest and that measured at the mouth. After obtaining the average attenuation curve from the volunteers, a discrete-time equalizer was designed and applied to crackles acquired from 30 patients with fibrosis, congestive heart failure, and pneumonia. The maximum frequency and two cycle duration indices measured from these crackles were modified by the equalization. The obtained results show that the equalizer improves the extraction of features from the crackles sounds. Equalization of crackles may contribute to better characterize the different diseases. © 2014 IEEE. Source


Bezerra R.D.S.,Federal Institute of Piaui | Silva M.M.F.,Interdisciplinary Laboratory for Advanced Materials LIMAV | Morais A.I.S.,Interdisciplinary Laboratory for Advanced Materials LIMAV | Santos M.R.M.C.,Interdisciplinary Laboratory for Advanced Materials LIMAV | And 2 more authors.
Journal of Environmental Chemical Engineering | Year: 2014

The natural biopolymer cellulose has been successfully used as sorbent due to its biocompatibility, degradability and chemical variability. For this application the pristine biomaterial was characterized through X-ray diffraction, infrared spectroscopy, scanning electron microscopy and carbon nuclear magnetic resonance. These results confirmed the biopolymer crystallinity. Its ability for ranitidine drug removal from aqueous solution was evaluated, investigating the effect of time, concentration, pH and temperature, to give favorable results in alkaline conditions. From the kinetic point of view, the sorptive process followed the pseudo-second-order model. The maximum sorption capacity gave 28.1; 32.1 and 32.9 mg g-1 at 298 ± 1; 308 ± 1 and 318 ± 1 K, respectively, after adjusting the data to the Freundlich model. The experimental data are in agreement that natural cellulose is a promising biopolymer to remove this drug from the environment. © 2013 Elsevier Ltd. Source


Dos S.c.l. Da Silva A.P.,Federal University of Piaui | Lopes J.S.L.,Federal University of Piaui | De S. Vieira P.,Federal University of Piaui | E.a. Pinheiro E.,Federal Institute of Piaui | And 5 more authors.
Pharmacology Biochemistry and Behavior | Year: 2014

Garcinielliptone FC (GFC) isolated from hexanic fraction seed extract of species Platonia insignis Mart. It is widely used in folk medicine to treat skin diseases in both humans and animals as well as the seed decoction has been used to treat diarrheas and inflammatory diseases. However, there is no research on GFC effects in the central nervous system of rodents. The present study aimed to evaluate the GFC effects at doses of 25, 50 or 75 mg/kg on seizure parameters to determine their anticonvulsant activity and its effects on amino acid (γ-aminobutyric acid (GABA), glutamine, aspartate and glutathione) levels as well as on acetylcholinesterase (AChE) activity in mice hippocampus after seizures. GFC produced an increased latency to first seizure, at doses 25 mg/kg (20.12 ± 2.20 min), 50 mg/kg (20.95 ± 2.21 min) or 75 mg/kg (23.43 ± 1.99 min) when compared with seized mice. In addition, GABA content of mice hippocampus treated with GFC75 plus P400 showed an increase of 46.90% when compared with seized mice. In aspartate, glutamine and glutamate levels detected a decrease of 5.21%, 13.55% and 21.80%, respectively in mice hippocampus treated with GFC75 plus P400 when compared with seized mice. Hippocampus mice treated with GFC75 plus P400 showed an increase in AChE activity (63.30%) when compared with seized mice. The results indicate that GFC can exert anticonvulsant activity and reduce the frequency of installation of pilocarpine-induced status epilepticus, as demonstrated by increase in latency to first seizure and decrease in mortality rate of animals. In conclusion, our data suggest that GFC may influence in epileptogenesis and promote anticonvulsant actions in pilocarpine model by modulating the GABA and glutamate contents and of AChE activity in seized mice hippocampus. This compound may be useful to produce neuronal protection and it can be considered as an anticonvulsant agent. © 2014 Elsevier Inc. Source

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