Physical factors affecting plasmid DNA compaction in stearylamine-containing nanoemulsions intended for gene delivery

Cationic lipids have been used in the development of non-viral gene delivery systems as lipoplexes. Stearylamine, a cationic lipid that presents a primary amine group when in solution, is able to compact genetic material by electrostatic interactions. In dispersed systems such as nanoemulsions this lipid anchors on the oil/water interface confering a positive charge to them. The aim of this work was to evaluate factors that influence DNA compaction in cationic nanoemulsions containing stearylamine. The influence of the stearylamine incorporation phase (water or oil), time of complexation, and different incubation temperatures were studied. The complexation rate was assessed by electrophoresis migration on agarose gel 0.7%, and nanoemulsion and lipoplex characterization was done by Dynamic Light Scattering (DLS). The results demonstrate that the best DNA compaction process occurs after 120 min of complexation, at low temperature (4 ± 1 °C), and after incorporation of the cationic lipid into the aqueous phase. Although the zeta potential of lipoplexes was lower than the results found for basic nanoemulsions, the granulometry did not change. Moreover, it was demonstrated that lipoplexes are suitable vehicles for gene delivery. © 2012 by the authors; licensee MDPI, Basel, Switzerland.

Automated determination of the orientation of dust devil tracks in mars orbiter images

The paper presents and evaluates three methods for automatically estimating the main orientation of Martian dust devil tracks in MOC and HiRISE images. Inferring such information about dust devils from their tracks is important to better understand the near surface wind. The methods considered were based on gradient direction, directional openings and morphological granulometry. The accuracy of the methods was asserted by comparing the results to a set of directions estimated visually and assumed to be the ground truth. The higher accuracy was reached using directional openings. Besides, the directions inferred by this method were compared to those predicted by the GCM and the results agreed. © 2013 COSPAR.

Biosorption of cadmium (II) and lead (II) from aqueous solution using exopolysaccharide and biomass produced by Colletotrichum sp.

The biosorption of Cd(II) and Pb(II) ions on biomass and exopolysaccharide (EPS) produced by Colletotrichum sp. fungus has been investigated as a function of contact time, initial pH, initial metal ion concentration, and initial adsorbent concentration in a batch system. Adsorption equilibrium was described by Freundlich and Langmuir isotherms. Adsorption was characterized through granulometry, SEM and EDX analysis. Then, studies were performed to regenerate the adsorbent. Biosorption of metals by biomass and EPS were best described by the Langmuir and Freundlich isotherm, respectively. Results of thermodynamic investigations showed that adsorption reactions were spontaneous (ΔG° < 0), exothermal, and mainly physical. The EPS was able to remove 79 and 98% of cadmium and lead, respectively, and the biomass removed 85 and 84% of cadmium and lead, respectively, in a solution with initial concentration 100 mg L-1, and the four adsorption-desorption cycles of all adsorbents showed up with great regenerative capacity and relative stability after these four cycles, the high potential of these biological materials in sorption has been shown. © 2013 Copyright Balaban Desalination Publications.

Caracterização química da farinha de vísceras de avestruz e seu valor nutritivo para tilápia-do-Nilo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Aproveitamento de rejeitos oriundos da extração de minério de ferro na fabricação de cerâmicas vermelhas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Culturas de cobertura, doses e tipos de calcário em superfície na implantação do sistema plantio direto com a cultura da soja irrigada

Pós-graduação em Agronomia - FEIS

Reconstrução paleolimnológica da eutrofização na represa Guarapiranga com base em multitraçadores biogeoquímicos

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Caracterização pedométrica de atributos de argissolos coesos do leste Maranhense

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Influência do grau de moagem de ingredientes amiláceos utilizados em rações extrusadas sobre os aspectos digestivos e respostas metabólicas em cães

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo geoquímico de solos em áreas degradadas no município de Sobral (CE) com vistas à sua recuperação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caracterização dos diamantes da província kimberlítica de Juína (MT), e distritos diamantíferos de Espigão D'Oeste (RO), Cacoal (RO) e Diamantina (MG)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Características dos substratos no desenvolvimento, nutrição e produção de gérbera (Gerbera jamesonii) em vaso

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variação granulométrica de casca de pinus no desenvolvimento e produção de gérbera (Gerbera jamesonii L.)

Pós-graduação em Agronomia (Horticultura) - FCA

Mapeamento de atributos do solo para o planejamento da irrigação sob pivô central

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resistência mecânica da madeira de eucalyptus saligna unidas por adesivo poliuretano para diferentes acabamentos de superfície

Pós-graduação em Engenharia Mecânica - FEG