Saúde bucal e cuidado odontológico: representações sociais de mães usuárias de um serviço público de saúde

Objetivo: identificar as representações sociais de mães de crianças da faixa etária de zero a cinco anos de idade do Núcleo de Saúde da Família IV, em Ribeirão Preto-SP, procurando saber o que pensam sobre saúde bucal e tratamento odontológico. Método: trata-se de pesquisa qualitativa, sendo utilizada a entrevista semi-estruturada para a coleta dos dados e a análise de conteúdo. Resultados: constatou-se grande dificuldade das mães em se expressar a respeito do que é, para elas, saúde. Para essas mães a saúde bucal está relacionada com normas de higiene e dietéticas e também com a ida ao dentista, restringindo-se na preocupação com a estética e pouco com a função. Já em relação ao tratamento odontológico, a grande maioria demonstrou apresentar medo, causado pela sua experiência anterior com o tratamento. A assistência particular está associada à pontualidade e ao atendimento da maneira desejada enquanto o tratamento oferecido pelo setor público à demora e à falta de equipamentos e materiais. A humanização no atendimento e competência do profissional emergiram como dois aspectos importantes, e podem estar determinando a decisão de ir ou não ao dentista. Conclusões: A expressão saúde bucal foi associada à assistência odontológica. O atendimento pelo setor privado foi referido como o que mais se aproxima do tipo ideal de assistência odontológica

On quantum integrability of the Landau-Lifshitz model

We investigate the quantum integrability of the Landau-Lifshitz (LL) model and solve the long-standing problem of finding the local quantum Hamiltonian for the arbitrary n-particle sector. The particular difficulty of the LL model quantization, which arises due to the ill-defined operator product, is dealt with by simultaneously regularizing the operator product and constructing the self-adjoint extensions of a very particular structure. The diagonalizibility difficulties of the Hamiltonian of the LL model, due to the highly singular nature of the quantum-mechanical Hamiltonian, are also resolved in our method for the arbitrary n-particle sector. We explicitly demonstrate the consistency of our construction with the quantum inverse scattering method due to Sklyanin [Lett. Math. Phys. 15, 357 (1988)] and give a prescription to systematically construct the general solution, which explains and generalizes the puzzling results of Sklyanin for the particular two-particle sector case. Moreover, we demonstrate the S-matrix factorization and show that it is a consequence of the discontinuity conditions on the functions involved in the construction of the self-adjoint extensions.

A hybrid material assembled by anthocyanins from acai fruit intercalated between niobium lamellar oxide

Organic-inorganic hybrid materials can be prepared dispersing organic species into well-defined inorganic nanoblocks. This paper describes the immobilization of natural dyes from the extract of the Brazilian acai-fruit into two types of layered hexaniobate precursors derived from H(2)K(2)Nb(6)O(17): (i) colloidal dispersion of niobate exfoliated nanoparticles and (ii) niobate pre-intercalated with tetraethylammonium cations (TEA(+)). The restacking of exfoliated particles in the presence of acai anthocyanins promotes their intercalation and produces stacked layers showing large basal spacing (ca. 50 angstrom). The TEA(+) pre-intercalated niobate provides particles with lower content of dye species than the exfoliated precursor but with higher degree of organization and regularity according to X-ray diffraction data and images obtained by electron microscopies. Vibrational (FTIR and Raman) and (13)C NMR spectroscopies indicate the presence of flavylium cations in the hybrid materials and spectral profiles characteristic of glycosylated anthocyanidins. According to thermal analysis results, the purplish hybrids materials are more stable than the free acai-dyes. One hybrid sample was heated under air up to 170 degrees C and maintained at this temperature for 240 min. No weight loss events were observed and the sample retained its original color, indicating that the intercalation of anthocyanin into hexaniobate increases its thermal stability. Considering the structural, chemical, optical and thermal properties of the synthesized hybrid materials, they might be good candidates to be investigated for future specialized applications.

Polymer matrix sensitizing effect on photoluminescence properties of Eu(3+)-beta-diketonate complex doped into poly-beta-hydroxybutyrate (PHB) in film form

In this work is reported the sensitization effect by polymer matrices on the photoluminescence properties of diaquatris(thenoyltrifluoroacetonate)europium(III), [Eu(tta)(3)(H(2)O)(2)], doped into poly-beta-hydroxybutyrate (PHB) with doping percentage at 1, 3, 5, 7 and 10% (mass) in film form. TGA results indicated that the Eu(3+) complex precursor was immobilized in the polymer matrix by the interaction between the Eu(3+) complex and the oxygen atoms of the PHB polymer when the rare earth complex was incorporated in the polymeric host. The thermal behaviour of these luminescent systems is similar to that of the undoped polymer, however, the T(onset) temperature of decomposition decreases with increase of the complex doping concentration. The emission spectra of the Eu(3+) complex doped PHB films recorded at 298 K exhibited the five characteristic bands arising from the (5)D(0) -> (7)F(J) intraconfigurational transitions (J = 0-4). The fact that the quantum efficiencies eta of the doped film increased significantly revealed that the polymer matrix acts as an efficient co-sensitizer for Eu(3+) luminescent centres and therefore enhances the quantum efficiency of the emitter (5)D(0) level. The luminescence intensity decreases, however, with increasing precursor concentration in the doped polymer to greater than 5% where a saturation effect is observed at this specific doping percentage, indicating that changes in the polymeric matrix improve the absorption property of the film, consequently quenching the luminescent effect.

Analytical solutions for geometrically nonlinear trusses

This paper presents an analytical method for analyzing trusses with severe geometrically nonlinear behavior. The main objective is to find analytical solutions for trusses with different axial forces in the bars. The methodology is based on truss kinematics, elastic constitutive laws and equilibrium of nodal forces. The proposed formulation can be applied to hyper elastic materials, such as rubber and elastic foams. A Von Mises truss with two bars made by different materials is analyzed to show the accuracy of this methodology.

The use of electrospray ionization tandem mass spectrometry on the structural characterization of novel asymmetric metallo-organic supermolecules, based on pentafluorophenylporphyrins and ruthenium complexes

The novel asymmetric metallo-organic triads cis- and trans-[B(4-py)BPFPH(2){Ru(3)O(Ac)(6)(py)(2)}(Ru(bpy)(2)Cl}](PF(6))(2) (5a,b) for which cis- and trans-B(4-py)BPFPH(2)=5,10-bis(pentafluorophenyl)-15,20-bis(4-pyridyl)porphyrin and 5,15-bis(pentafluorophenyl)-10,20-bis(4-pyridyl)porphyrin, respectively; Ac = acetate; py = pyridine and bpy = 2,2`-bipyridine, as well as their corresponding monosubstituted dyads cis- and trans-[B(4-py)BPFPH(2){Ru(3)O(Ac)(6)(py)(2)}]PF(6) (4a,b) have been structurally characterized via electrospray ionization mass spectrometry (ESI-MS and ESI-MS/MS). The ESI-MS of dyads 4a,b display two characteristic Ru-multicomponent clusters of isotopologue ions corresponding to singly charged ions 4a,b(+) of m/z 1629 and doubly charged ions [4a,b+H](2+) of m/z 815 and the triads 5a,b are detected by ESI-MS as the intact doubly charged cluster of isotopologue ions of m/z 1039 [5a,b](2+). The ESI-MS/MS of 4a,b(+), [4a,b+H](2+) and [5a,b](2+) reveal characteristic dissociation pathways, which confirm the structural assignments providing additional information on the intrinsic binding strengths of the gaseous ions. Although the gas-phase behavior of each pair of isomers was rather similar, the less symmetric dyads 4a,b are distinguished via the (1)H NMR spectral profile of the pyrrolic signals. Exploratory photophysical assays have shown that both modifying motifs alter the porphyrinic core emission profile, opening the possibility to use these asymmetric systems as photophysical devices. (C) 2008 Elsevier Ltd. All rights reserved.