Synthesis, characterization and electrochemical study of layered double hydroxides intercalated with 2-thiophenecarboxylate anions

The synthesis, characterization, and electrochemical study of the Zn(II)-Al(III) and Zn(II)-Cr(III) Layered Double Hydroxides (LDHs) containing 2-thiopenecarboxylate as the interlayer anions are described. The LDHs were prepared by the constant pH coprecipitation technique followed by hydrothermal treatment for 72 h. The materials were analyzed by PXRD, FT-IR, C-13 CP-MAS, EDX, TEM, and CV. The presence of the organic heterocyclic anions was confirmed by FT-IR and the related solid-state C-13 NMR data strongly suggested that these were dimerised during coprecipitation. Accordingly, the basal spacing found by the X-ray technique was similar to 15.3 Angstrom, a distance coincident with the formation of bilayers of the intercalated anions. The structural organization of all the new materials was greatly enhanced by hydrothermal treatment, as shown by PXRD. The improved organization of the bilayered structures had a strong influence in the electrochemical behaviour of clay-modified electrodes produced with these materials, such as the diminished resistance to the ionic flow through the LDHs films. (C) 2003 Elsevier Ltd. All rights reserved.

Glasses in the SbPO4-WO3 system

Glasses in the binary system (100 - x)SbPO4-xWO3 (20 <= x <= 60, x in mol%) have been prepared and characterized. Differential thermal analysis (DTA) shows that the glass transition temperature, T-g increases from 412 degrees C, for samples containing 20 mol% of WO3 to 481 degrees C observed for glass containing 60 mol%. Sample containing 40 mol% in WO3 were observed to be the most stable against devitrification. The structural organization of the glasses has been studied by using Fourier transform infra-red (FTIR), Raman, P-31 Magic angle spinning (MAS) and spin echo nuclear magnetic resonance (NMR) spectroscopies. Results suggest two distinct networks comprising the glass structure, one with high SbPO4 content and the other characteristic of the highest WO3 content samples. The glasses present photochromic properties. Colour changes are observed for samples after exposure to ultraviolet or visible laser light. XANES, at L-1 absorption edge of tungsten, suggests partial reduction from W6+ to W5+ species during the laser irradiation. The photochromic effects and the colour changes, promoted by laser excitation, are reversible and easily removed by heat for during 1 h at 150 degrees C. Subsequent 'write/erase' cycles can be done without degradation of the glasses. (C) 2007 Elsevier B.V. All rights reserved.

In2O3 microcrystals obtained from rapid calcination in domestic microwave oven

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Restabelecimento funcional do tendão extensor digital longo submetido a ressecção parcial em equinos: Observação macroscópica, histopatológica e ultra-sonográfica

The objective of this work was to study the macroscopic, ultrasonographic and histopathologic aspects from the newly formed cicatricial tissue at the site of the partial resection of the long digital extensor tendon in 10 equines at the moment of functional restoration of the limb with the animal in walk locomotion. The macroscopic exam was performed every 48 hours, the planimetric mensuration every 10 days, the ultrasonographic exam every 15 days and the histopathologyc exam at the end of the study. The wounds showed granulation tissue in retraction, without total lesion epithelization, and the aspects ultrasonographics revealed wound healing with newly formed tissues with variable density and high neovascularization without tendon structural reorganization. The histopathology showed newly formed vascularized tissue, with leukocytic infiltrate and collagenous deposition without full epithelization. The cicatrization tissue formed in the resection region of the tendon, immature and without the structural organization of the normal tendon, showed to be able to functional restoration of the operated limb.

Orphan nuclear receptor NGFI-B forms dimers with nonclassical interface

The orphan receptor nerve growth factor-induced B (NGFI-B) is a member of the nuclear receptor's subfamily 4A (Nr4a). NGFI-B was shown to be capable of binding both as a monomer to an extended half-site containing a single AAAGGTCA motif and also as a homodimer to a widely separated everted repeat, as opposed to a large number of nuclear receptors that recognize and bind specific DNA sequences predominantly as homo- and/or heterodimers. To unveil the structural organization of NGFI-B in solution, we determined the quaternary structure of the NGFI-B LBD by a combination of ab initio procedures from small-angle X-ray scattering (SAXS) data and hydrogen-deuterium exchange followed by mass spectrometry. Here we report that the protein forms dimers in solution with a radius of gyration of 2.9 nm and maximum dimension of 9.0 nm. We also show that the NGFI-B LBD dimer is V-shaped, with the opening angle significantly larger than that of classical dimer's exemplified by estrogen receptor (ER) or retinoid X receptor (RXR). Surprisingly, NGFI-B dimers formation does not occur via the classical nuclear receptor dimerization interface exemplified by ER and RXR, but instead, involves an extended surface area composed of the loop between helices 3 and 4 and C-terminal fraction of the helix 3. Remarkably, the NGFI-B dimer interface is similar to the dimerization interface earlier revealed for glucocorticoid nuclear receptor (GR), which might be relevant to the recognition of cognate DNA response elements by NGFI-B and to antagonism of NGFI-B-dependent transcription exercised by GR in cells. Published by Cold Spring Harbor Laboratory Press. Copyright © 2007 The Protein Society.

Cultivo de condrócitos equinos e avaliação de sua condrogenicidade mediante implante de células associadas ao hidrogel em subcutâneo de camundongos atímicos

Pós-graduação em Medicina Veterinária - FMVZ

Restabelecimento funcional do tendão extensor digital longo submetido à tenectomia em eqüinos: observação macroscópica, ultra-sonográfica e histopatológica

Pós-graduação em Medicina Veterinária - FMVZ

Estudo de propriedades elétricas em sistemas orgânicos e inorgânicos correlacionados

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo no grau de ordem-desordem no 'SR''BI IND 2''NB IND 2''O IND.9 pela influência do íon 'EU IND.3'/' e tratamento térmico por microondas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito das terras raras nas propriedades óticas do BaM'O.IND.3'(M==Zr, Ti)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Motivações funcionais da gradação entre construções encaixadas nominais e verbais

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análise da influência do calço e do movimento de inclinação lateral da coluna vertebral em indivíduos com escoliose idiopática

Pós-graduação em Ciências da Motricidade - IBRC

Propriedade fotoluminescente dos materiais 'CA''TI''O IND.3' e 'CA IND.1-x''EU IND.x''TI''O IND.3'

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Patrimônio urbano de Londrina

Pós-graduação em Geografia - IGCE

Complexos de lantanídeos contendo ligantes organofosforados como matrizes para materiais luminescentes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)