Electrostatic and Hydrophobic Interactions Involved in CNT Biofunctionalization with Short ss-DNA

This work is aimed at studying the adsorption mechanism of short chain 20-mer pyrimidinic homoss-DNA (oligodeoxyribonucleotide, ODN: polyC(20) and polyT(20)) onto CNT by reflectometry. To analyze the experimental data, the effective-medium theory using the Bruggemann approximation represents a Suitable optical model to account for the surface properties (roughness, thickness, and optical constants) and the size of the adsorbate. Systematic information about the involved interactions is obtained by changing the physicochemical properties of the system. Hydrophobic and electrostatic interactions are evaluated by comparing the adsorption oil hydrophobic CNT and oil hydrophilic silica and by Modulating the ionic Strength With and without Mg(2+). The ODN adsorption process oil CNT is driven by hydrophobic interactions only when the electrostatic repulsion is Suppressed. The adsorption mode results in ODN molecules in a side-on orientation with the bases (nonpolar region) toward the surface. This unfavorable orientation is partially reverse by adding Mg(2+). On the other hand, the adsorption oil silica is dominated by the strong repulsive electrostatic interaction that is screened at high ionic strength or mediated by Mg(2+). The cation-mediated process induces the interaction of the phosphate backbone (polar region) with the surface, leaving the bases free for hybridization. Although the general adsorption behavior of the pyrimidine bases is the same, polyC(20) presents higher affinity for the CNT Surface due to its acid-base properties.

2-Aminopurine non-radiative decay and emission in aqueous solution: A theoretical study

The minimum energy path along the lowest-lying pi pi* excited state of 2-aminopurine was calculated to elucidate the mechanisms of radiationless decay and emission in water. The sequential Monte Carlo quantum mechanics approach with a multiconfigurational and perturbative description of the wave function was employed to compute the minimum, transition state, and conical intersection. It was found that the barrier in the potential energy surface to access the conical intersection funnel increases in aqueous environment, making the system prone to enlarge the emission yield. These results rationalize the observed enhancement of emission in 2-aminopurine upon increasing of the solvent polarity. (c) 2008 Elsevier B.V. All rights reserved.

Spectroscopic and theoretical studies of some 2-ethylsulfinyl-(4 `-substituted)-phenylthioacetates

The analysis of the IR nu(co) bands of the 2-ethylsulfinyl-(4`-substituted)-phenylthioacetates 4`-Y-C(6)H(4)SC(O)CH(2)S(O)Et (Y = NO(2) 1, Cl 2, Br 3, H 4, Me 5, OMe 6) supported by B3LY/6-31G(d,p) calculations along with the NBO analysis for 1.4 and 6 and X-ray analysis for 3, indicated the existence of four gauche (q-g-syn, g(3)-syn. g(1)-atin and q-g(2)-syn) conformers for 1-6 The calculations reproduce quite well the experimental results, i e the computed q-g-syn and g3-syn conformers correspond in the IR spectrum (in solution), to the nu(co) doublet higher frequency component of larger intensity, while the computed grant, conformer correspond to the nu(co) doublet lower frequency component (in solution) NBO analysis showed that the n(s) -> pi(center dot)(c1=o2), no(co) -> sigma(c1-s3), no(co) -> sigma(c1-c4) orbital interactions are the main factors which stabilize the q-g-syn, g(3)-syn, g(1)-anti and q-g(2)-syn conformers for 1, 4 and 6 The no(co) -> sigma(c1-s3) interaction which stabilizes the q-g-syn, g(3)-syn and q-g(2)-syn conformers into a larger extent than the granti conformer, is responsible for the larger tto frequencies of the former conformers relative to the latter one. The q-g-syn, g(3)-syn and q-g(2)-syn conformers are further stabilized sigma(c4-s5) -> pi(co)center dot (strong). pi(co)/sigma(c1-c4,) no(co) -> sigma(c6-H17[Et]) (weak) and pi(co)/sigma(c4-c5) pi(co) (strong) orbital interactions. The q-g-syn conformer is also stabilized by sigma(c4-s5) -> pi(center dot)(co) (strong), pi(co)/sigma(c4-c5).no(co) -> sigma(c6-H17[Et]), pi(C9=C11[ph]) -> sigma(c4-H6x-CH2]) (weak). no((SO)) -> sigma(C11-H23[ph]) (medium) pi(co)/sigma(c4-c5)(strong) orbital interactions. The q-g-syn conformei is further stabilized by the n(S5) O((C))(8-) S((SO))(8+) attractive Coulornbic interaction while the q-g(2)-syn conformer is destabilized by the n55 0,8c-0) repulsive Coulombic interaction. This analysis indicates the following conformer stabilization order. q-g-syn, g(3)-syn > g(1)-anti >> q-g(2)-syn X-ray single crystal analysis of 3 indicates that it assumes in the solid a distorted q-g(2)-syn geometry which is stabilized through almost the same orbital and Coulombic interaction which takes place for the q-g(2)-syn conformer, in the gas, along with dipole moment coupling and a series intermolecular C-HO0 interactions. (C) 2010 Elsevier B V All rights reserved

Microbial diversity associated with algae, ascidians and sponges from the north coast of Sao Paulo state, Brazil

Little is known about the microbial diversity associated with marine macroorganisms, despite the vital role microorganisms may play in marine ecosystems. The aim of the present study was to investigate the diversity of bacteria and fungi isolated from eight marine invertebrate and one algae samples. Data derived from ARDRA and sequencing analyses allowed the identification of marine-derived microorganisms isolated from those samples. Microbial strains identified up to the genus level revealed 144 distinct ribotypes out of 256 fungal strains and 158 distinct ribotypes out of 181 bacterial strains. Filamentous fungi were distributed among 24 different genera belonging to Ascomycota, Zygomycota and Basidiomycota, some of which had never been reported in the literature as marine invertebrate-inhabiting fungi (Pestalotiopsis, Xylaria, Botrysphaeria and Cunnninghamella). Bacterial isolates were affiliated to 41 different genera, being Bacillus, Ruegeria, Micrococcus, Pseudovibrio and Staphylococcus the most abundant ones. Results revealed an unexpected high microbial diversity associated to the macroorganisms which have been collected and suggested the selection of certain microbial taxonomic groups according to the host. The combined data gathered from this investigation contribute to broaden the knowledge of microbial diversity associated to marine macroorganisms, including as a promising source for the discovery of new natural products. (C) 2009 Elsevier GmbH. All rights reserved.

Un estudio de La Sombra del Viento de Carlos RuizZafón desde una perspectiva de género

Esta tesina tiene el propósito de analizar las características de algunos de lospersonajes principales de La Sombra del Viento de Carlos Ruiz Zafón desde un punto de vistade género. El estudio se basa en diferentes teorías de género que pretenden funcionar comoherramientas para poder destacar las diferencias entre las descripciones femeninas y lasmasculinas que aparecen en la obra. Primero, definimos y concretamos el término género conla ayuda de las teorías de Yvonne Hirdman. En segundo lugar, presentamos la teoría deldualismo, de acuerdo con la cual Lena Gemzöe hace una división entre las cualidadesmasculinas y femeninas. El objetivo de nuestro estudio ha sido hacer un análisis de lascaracterísticas de algunos de los personajes principales de para demostrar si existenconstrucciones de identidad de género desde una perspectiva dualista. Como resultado denuestro estudio podemos afirmar que Zafón refuerza la división entre las cualidadesmasculinas y femeninas. Los personajes masculinos son descritos como fuertes, valientes,lógicos, intelectuales e independientes. Paralelamente, las mujeres son descritas como débiles,cobardes, intuitivas y dependientes. Además, consideramos que Zafón da a todos lospersonajes masculinos mayor espacio, estatus y protagonismo en el desarrollo de la historia.En todo momento, queda claro que Zafón crea de forma inconsciente el orden de género yrefuerza así las diferencias sexuales.

Marketing Político e Redes Sociais: reflexos nas eleições 2010 à presidência da República

E-book disponível na íntegra em: http://politicom.com.br/wp-content/uploads/2012/02/ebookpoliticomunisal.pdf#page=64

Princípios da ONU para a educação ambiental: estudo de caso nas instituições de ensino superior brasileiras

Dissertação apresentada ao Programa de Pós-graduação em Administração da Universidade Municipal de São Caetano do Sul como requisito para a obtenção do título de Mestre em Administração

Conflitos e obstáculos operacionais em gestão de projetos inovadores: um estudo empírico

Este artigo objetiva descrever o modo como conflitos e obstáculos operacionais se manifestam em gestão de projetos inovadores em um banco de desenvolvimento (BD). A pesquisa possui uma abordagem qualitativa e exploratória; a coleta de dados foi realizada por meio de entrevistas com consultores e gerentes de projetos e de documentos do Banco de Desenvolvimento sobre gestão de projetos; as entrevistas foram submetidas à análise de conteúdo com uso do software Atlas.ti. Este estudo revelou que a gestão de projetos, em seu novo modelo implantado, depara-se com dificuldades semelhantes àquelas presentes nas hierarquias tradicionais. Observou-se que conflitos relacionados a interesses, valores, aspectos psicológicos e obstáculos operacionais são intrínsecos ao ciclo de vida de projetos inovadores, cuja implantação, para ser eficaz, requer muita capacidade política de seus líderes.