The International Physical Activity Questionnaire-long form overestimates self-reported physical activity of Brazilian adults

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

Physicochemical characterization of collagen fibers and collagen powder for self-composite film production

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

Efficient microwave-assisted hydrothermal synthesis of CuO sea urchin-like architectures via a mesoscale self-assembly

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

Electrochemical and spectroscopic characterization of screen-printed gold-based electrodes modified with self-assembled monolayers and Tc85 protein

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

Self-assembly of cyclometallated Pd(II) compounds directed by C-H center dot center dot center dot pi interactions: A structural evidence for metalloaromaticity in a cyclopalladated ring

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Biochemical characterization of Neurospora crassa glycogenin (GNN), the self-glucosylating initiator of glycogen synthesis

Glycogenin acts in the initiation step of glycogen biosynthesis by catalyzing a self-glucosylation reaction. In a previous work [de Paula et al., Arch. Biochem. Biophys. 435 (2005) 112-124], we described the isolation of the cDNA gnn, which encodes the protein glycogenin (GNN) in Neurospora crassa. This work presents a set of biochemical and functional studies confirming the GNN role in glycogen biosynthesis. Kinetic experiments showed a very low GNN K-m (4.41 mu M) for the substrate UDP-glucose. Recombinant GNN was produced in Escherichia coli and analysis by mass spectroscopy identified a peptide containing an oligosaccharide chain attached to Tyr196 residue. Site-directed mutagenesis and functional complementation of a Saccharomyces cerevisiae mutant strain confirmed the participation of this residue in the GNN self-glucosylation and indicated the Tyr198 residue as an additional, although less active, glucosylation site. The physical interaction between GNN and glycogen synthase (GSN) was analyzed by the two-hybrid assay. While the entire GSN was required for full interaction, the C-terminus in GNN was more important. Furthermore, mutation in the GNN glucosylation sites did not impair the interaction with GSN. (c) 2005 Published by Elsevier B.V. on behalf of the Federation of European Biochemical Societies.

Self-assembly of metallosupramolecules directed by (N-H)(2)center dot center dot center dot SCN-M (M = Co, Ni), C-H center dot center dot center dot pi and pi-pi synthons

This work deals with the synthesis, spectroscopic and structural investigation of pyrazolyl complexes of the type trans-[M(NCS)(2)(HPz)(4)] {M=Co (1), Ni (2); HPz=pyrazole}. Single crystal X-ray studies on 1 and 2 reveal the formation of similar supramolecular arrangements derived from self-assembly of monomers linked together through intermolecular N-H center dot center dot center dot SCN hydrogen bonds, C-H center dot center dot center dot pi interactions and pi-pi stacking. (c) 2005 Elsevier B.V. All rights reserved.

Self-assembly of Pd(II) pyrazolyl complexes to 1-D hydrogen-bonded coordination polymers

This work describes the synthesis and characterization of two novel Pd(II) pyrazolyl complexes of the type [PdX2(HdmPz)(2)](n) {X=SCN- (1), N-3(-) (2); HdmPz=3,5-dimethylpyrazole} that self-assemble through N-H...NCS or N-H...NNN hydrogen bonds to yield infinite one-dimensional chains, as confirmed by single crystal X-ray study on 1. The expected solid state polymeric structure for 2 is slowly broken up in CHCl3 Solution, leading to an equilibrium mixture of cis and trans-[Pd(N-3)(2)(HdmPz)(2)] monomers, as demonstrated by time-dependent IR and NMR studies. (C) 2003 Elsevier B.V. B.V. All rights reserved.

Low-weight coordination polymers derived from the self-assembly reactions of Pd(II) pyrazolyl compounds and azide ion

The low-weight Pd(II) coordination polymers [(N(3))(HL)Pd {Pd(3)(mu-N(3))(mu-L)(5)}10(mu-L)(2)Pd(L)(HL)]{L = Pz(-) (1); mPz(-) (2), IPz(-)(3)} and [(N(3))(HPz)Pd{Pd(6)(mu-N(3))(2)(mu-PZ)(5)(mu-L)(5)}(10)(mu-L)(2)Pd(Pz)(HPz)] {L = mPz(-) (4), dmPz(-) (5); IPz(-) (6)} {L = pyrazolate (Pz(-)), 4-methylpyrazolate(mPz(-)), 4-iodopyrazo late (IPz(-)), 3,5-dimethylpyrazolate (dmPz(-))} have been prepared in this work. IR spectra clearly indicated the exobidentate nature of pyrazolato ligands as well the end-on coordination mode of the azido group. The molecular weight determinations by osmometry indicated that the species have a low degree of polymerization (n = 10). NMR experiments showed two pyrazolate environments in a 2:1 ratio, being assigned to the six-membered ring Pd(mu-L)(2)Pd and the Pd(mu-N(3))(mu-L)Pd metallocycle, respectively. UV-visible spectroscopy gave further evidences for the oligomeric structures of 1-6. Some alternative structures for the isostructural polymers have been suggested. (c) 2005 Elsevier Ltd. All rights reserved.

The Meaningful Fractal Fuzzy Dimension Applied to the Design of Self Organizing Maps

This paper presents the principal results of a detailed study about the use of the Meaningful Fractal Fuzzy Dimension measure in the problem in determining adequately the topological dimension of output space of a Self-Organizing Map. This fractal measure is conceived by combining the Fractals Theory and Fuzzy Approximate Reasoning. In this work this measure was applied on the dataset in order to obtain a priori knowledge, which is used to support the decision making about the SOM output space design. Several maps were designed with this approach and their evaluations are discussed here.

Quartic fermion self-interactions in two-dimensional gauge theories

In this work we discuss the effect of quartic fermion self-interacting terms on the dynamically generated photon masses in 1+1 dimensions, for vector, chiral, and non-Abelian couplings. In the vector and chiral cases we find exactly the dynamically generated mass modified by the quartic term while in the non-Abelian case we find the dynamically generated mass associated with its Abelian part. We show that in the three cases there is a kind of duality between the gauge and quartic couplings. We perform functional as well as operator treatments allowing for the obtention of both fermion and vector field solutions. The structures of the Abelian models in terms of θ vacua are also addressed.

Polyacids self-dissociation model

This work deals with a model to interpret pH measurements of solutions of weak rodlike polyacids, in the absence of added salts or titrating base. The polyacid is modeled as a series of point charges discretely distributod in a straight line with a distance of closest approach for the protons and an average distance between dissociable monomers, projected in the polymer chain axis. Aside from these two geometrical parameters, the dissociation constant for the isolated monomer that describes the proton dissociated monomer interaction forms the basis of the model. The assumption of cylindrical symmetry and the adoption of the cell model lead to a form written in terms of elementary functions for the mean electrostatic potential. Values of pH (related to the proton concentration in a region beyond the influence of the polyacid) as a function of polymer concentration are displayed graphically for some values of the geometrical parameters and of the dissociation, constant. Theoretical predictions of pH values as a function of polymeric concentration are compared with measured values for poly-L-glutamic and polygalacturonic acids, and a good agreement is found. Theoretical values for the dissociation degree in terms of polymeric concentration are shown for the two experimentally investigated systems. These values are in a range appreciably smaller than what is usually studied as a result of titration.

Two-loop self-energy diagrams worked out with NDIM

In this work we calculate two two-loop massless Feynman integrals pertaining to self-energy diagrams using NDIM (Negative Dimensional Integration Method). We show that the answer we get is 36-fold degenerate. We then consider special cases of exponents for propagators and the outcoming results compared with known ones obtained via traditional methods.

New remarks on the linear constraint self-dual boson and Wess-Zumino terms

In this work we prove in a precise way that the soldering formalism can be applied to the Srivastava chiral boson (SCB), in contradiction with some results appearing in the literature. We promote a canonical transformation that shows directly that the SCB is composed of two Floreanini-Jackiw particles with the same chirality in which the spectrum is a vacuumlike one. As another conflicting result, we prove that a Wess-Zumino (WZ) term used in the literature consists of a scalar field, once again denying the assertion that the WZ term adds a new degree of freedom to the SCB theory in order to modify the physics of the system. © 2001 The American Physical Society.

On numerical simulations of a nonlinear self-excited system with two non-ideal sources

In this work, the dynamic behavior of self-synchronization and synchronization through mechanical interactions between the nonlinear self-excited oscillating system and two non-ideal sources are examined by numerical simulations. The physical model of the system vibrating consists of a non-linear spring of Duffing type and a nonlinear damping described by Rayleigh's term. This system is additional forced by two unbalanced identical direct current motors with limited power (non-ideal excitations). The present work mathematically implements the parametric excitation described by two periodically changing stiffness of Mathieu type that are switched on/off. Copyright © 2005 by ASME.