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Freitas L.D.S.,UFS | Dariva C.,Institute Tecnologia e Pesquisa ITP | Jacques R.A.,Federal University of Rio Grande do Sul | Caramao E.B.,Federal University of Rio Grande do Sul
Separation and Purification Technology | Year: 2013

Pressurized liquid extraction (PLE) is a useful technology for performing quick extractions of organic compounds from a variety of matrices. In the presented study, PLE of oil from grape seed was performed, and the effect of varying some experimental parameters, such as solvent, extraction time, flush, amount of sample, number of extraction cycles and temperature, was determined. The yield and the main characteristics of the produced oil were measured. It was found that the solvent choice has an important influence on the mass yield of the grape seed oil when performing PLE. The best yield results were achieved, under all experimental conditions, when using dichloromethane as the extraction solvent. The temperature and the number of extraction cycles also demonstrated an influence on the mass yield of the oil. © 2013 Elsevier B.V. All rights reserved. Source

Barreto F.J.N.,Federal University of Sergipe | Cipolotti R.,UFS
Jornal Brasileiro de Psiquiatria | Year: 2011

objective: Determinate prevalence of depressive symptoms in children and adolescents with sickle cell anemia, characterize and associate then with individuals data. Methods: A transversal study was conducted with people with sickle cell anemia from 7 to 17 years old, followed at a Pediatric Hematology Center, which fulfilled the Children's Depression Inventory (CDI). Results: A total of 76 children and adolescents were selected, considering a cut-of point of 13. Twenty-six patients (34,2%) had suggestive symptoms of depression. "Not able to be as good as others siblings" was the most scored item of CDI, and it prevailed significantly in that with CDI score higher or equal than 13, as the variables: having divorced or widowed parents, and family income lower or equal to R$ 510,00. The item "worries about pain" obtained high score whether depressive symptoms were present or not (p = 0,1). Conclusion: Depression in children and adolescents with sickle cell anemia remains poorly discussed. Data obtained indicates high rates of depressive symptoms in this population. Probably, early experience of parental separation and low family income may contribute to development of these symptoms. Source

Dutra J.D.L.,Pople Computational Chemistry Laboratory | Bispo T.D.,UFS | Freire R.O.,Pople Computational Chemistry Laboratory
Journal of Computational Chemistry | Year: 2014

In this study, we will be presenting LUMPAC (LUMinescence PACkage), which was developed with the objective of making possible the theoretical study of lanthanide-based luminescent systems. This is the first software that allows the study of luminescent properties of lanthanide-based systems. Besides being a computationally efficient software, LUMPAC is user friendly and can be used by researchers who have no previous experience in theoretical chemistry. With this new tool, we hope to enable research groups to use theoretical tools on projects involving systems that contain lanthanide ions. © 2014 Wiley Periodicals, Inc. Source

Souto-Maior F.N.,Federal University of Paraiba | Souto-Maior F.N.,Federal University of Campina Grande | De Carvalho F.L.D.,Federal University of Paraiba | De Morais L.C.S.L.,Federal University of Paraiba | And 3 more authors.
Pharmacology Biochemistry and Behavior | Year: 2011

Linalool oxide is a monoterpene that is found in some species of aromatic plants. The effects of the inhalation of linalool oxide (0.65%, 1.25%, 2.5% and 5.0% w/w) in the elevated plus-maze and light/dark box tests as animal models of anxiety were investigated in adult male mice and compared with the effects of the reference anxiolytic diazepam (0.5 and 2.0 mg/kg), administered intraperitoneally. Additionally, the effects of inhaled linalool oxide were investigated in the rotarod test. Linalool oxide significantly increased the number of visits to the open arms of the elevated plus-maze and the amount of time spent there as well as the total number of entries. In the light/dark box test, inhalation of linalool oxide led to an increase in the time spent by the mice in the brightly-lit chamber and in the number of times the animal crossed from one compartment to another. Performance on the rotarod was unaffected. Thus, inhaled linalool oxide was found to have anxiolytic properties in both animal models, without causing any motor deficit. These results suggest that inhalation of linalool oxide may be a useful means of counteracting anxiety. © 2011 Elsevier Inc. All rights reserved. Source

Rodrigues M.O.,University of Brasilia | Rodrigues M.O.,Federal University of Pernambuco | Dutra J.D.L.,UFS | Nunes L.A.O.,University of Sao Paulo | And 6 more authors.
Journal of Physical Chemistry C | Year: 2012

In this work, we report a theoretical and experimental investigation of the energy transfer mechanism in two isotypical 2D coordination polymers, ∞[(Tb 1-xEu x)(DPA)(HDPA)], where H 2DPA is pyridine 2,6-dicarboxylic acid and x = 0.05 or 0.50. Emission spectra of ∞[(Tb 0.95Eu 0.05)(DPA)(HDPA)] and ∞[(Tb 0.5Eu 0.5)(DPA)(HDPA)], (1) and (2), show that the high quenching effect on Tb 3+ emission caused by Eu 3+ ion indicates an efficient Tb 3+→Eu 3+ energy transfer (ET). The k ET of Tb 3+→ Eu 3+ ET and rise rates (k r) of Eu 3+ as a function of temperature for (1) are on the same order of magnitude, indicating that the sensitization of the Eu 3+5D 0 level is highly fed by ET from the 5D 4 level of Tb 3+ ion. The η ET and R 0 values vary in the 67-79% and 7.15 to 7.93 Å ranges. Hence, Tb 3+ is enabled to transfer efficiently to Eu 3+ that can occupy the possible sites at 6.32 and 6.75 Å. For (2), the ET processes occur on average with η ET and R 0 of 97% and 31 Å, respectively. Consequently, Tb 3+ ion is enabled to transfer energy to Eu 3+ localized at different layers. The theoretical model developed by Malta was implemented aiming to insert more insights about the dominant mechanisms involved in the ET between lanthanides ions. Calculated single Tb 3+→ Eu 3+ ETs are three orders of magnitude inferior to those experimentally; however, it can be explained by the theoretical model that does not consider the role of phonon assistance in the Ln 3+→ Ln 3+ ET processes. In addition, the Tb 3+→ Eu 3+ ET processes are predominantly governed by dipole-dipole (d-d) and dipole-quadrupole (d-q) mechanisms. © 2012 American Chemical Society. Source

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