Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 669 )

2018 ( 960 )

2017 ( 905 )

2016 ( 1265 )

Custom range...

Search Results: 1 - 10 of 556569 matches for " F. A. Machado "
All listed articles are free for downloading (OA Articles)
Page 1 /556569
Display every page Item
Skin fold: Localization and procedures
A.F. Machado
Motricidade , 2008,
Abstract: The skin fold method, also known as indirect method, utilized regression equations to predict body fat, where it is based on the relation between subcutaneous fat, internal fat and body density. However its use requires a long period of training from the appraisers, so that the results can be trusted. An important limitation on this method utilization is the difficult in standardizing measure points by the appraisers and the proceedings adopted during the process of evaluation. According to this, this study’s objective was to executed a review about the localization points to the skin fold mensuration and also about the adopted proceedings during the evaluation process to minimize the errors. Initially we studied the method trusty and after that the mensuration equipments, the proceedings and the skin fold mensuration localizations. Concluding that one of the requisites to be a good appraiser of skin fold is the knowledge of the repair points and proceedings adopted to get each skin fold are also too important to the measure success.
Charged right-handed currents in the leptoquark-bilepton flavordynamics chiral models
A. A. Machado,F. Pisano
Physics , 1998, DOI: 10.1142/S0217732399002303
Abstract: Flavordynamics chiral models of leptoquark fermions and bilepton gauge bosons with masses up to about 1 TeV, although coincident at low energy with the standard model, address the question of fermion mass hyerarchy and explain the flavor question. The presence of charged right-handed weak currents coupled to bileptons, which we point out herein, is another remarkable feature of these chiral theories.
Interactivity and Information- Communication Technologies in Chemical Engineering Classes  [PDF]
A. J. Santiago, C. E. da Silva, A. F. Machado, M. G. Muniz Washington
Open Journal of Social Sciences (JSS) , 2015, DOI: 10.4236/jss.2015.32002

In this paper, we propose a new contextualization of the so-called scientific method in teaching practices in science and engineering education. We report an objectification in information and communication technologies (ICT) for simulate the reaction rates during an class and its inclusion in the above-mentioned pedagogical purpose, that, in tune with the current realities of schools, rehearses reflections of a future with another horizon for teaching/learning engineering and other sciences.

Pitfalls of artificial grouping and stratification of scientific journals based on their Impact Factor: a case study in Brazilian Zoology
Machado, Fábio A.;Zaher, Hussam;
Zoologia (Curitiba) , 2010, DOI: 10.1590/S1984-46702010000400002
Abstract: the present contribution explores the impact of the qualis metric system for academic evaluation implemented by capes (coordination for the development of personnel in higher education) upon brazilian zoological research. the qualis system is based on the grouping and ranking of scientific journals according to their impact factor (if). we examined two main points implied by this system, namely: 1) its reliability as a guideline for authors; 2) if zoology possesses the same publication profile as botany and oceanography, three fields of knowledge grouped by capes under the subarea "boz" for purposes of evaluation. additionally, we tested capes' recent suggestion that the area of ecology would represent a fourth field of research compatible with the former three. our results indicate that this system of classification is inappropriate as a guideline for publication improvement, with approximately one third of the journals changing their strata between years. we also demonstrate that the citation profile of zoology is distinct from those of botany and oceanography. finally, we show that ecology shows an if that is significantly different from those of botany, oceanography, and zoology, and that grouping these fields together would be particularly detrimental to zoology. we conclude that the use of only one parameter of analysis for the stratification of journals, i.e., the impact factor calculated for a comparatively small number of journals, fails to evaluate with accuracy the pattern of publication present in zoology, botany, and oceanography. while such simplified procedure might appeals to our sense of objectivity, it dismisses any real attempt to evaluate with clarity the merit embedded in at least three very distinct aspects of scientific practice, namely: productivity, quality, and specificity.
Shape instabilities in vesicles: a phase-field model
F. Campelo,A. Hernandez-Machado
Quantitative Biology , 2007, DOI: 10.1140/epjst/e2007-00077-y
Abstract: A phase field model for dealing with shape instabilities in fluid membrane vesicles is presented. This model takes into account the Canham-Helfrich bending energy with spontaneous curvature. A dynamic equation for the phase-field is also derived. With this model it is possible to see the vesicle shape deformation dynamically, when some external agent instabilizes the membrane, for instance, inducing an inhomogeneous spontaneous curvature. The numerical scheme used is detailed and some stationary shapes are shown together with a shape diagram for vesicles of spherical topology and no spontaneous curvature, in agreement with known results.
Dynamic model and stationary shapes of fluid vesicles
F. Campelo,A. Hernandez-Machado
Quantitative Biology , 2006, DOI: 10.1140/epje/i2005-10079-5
Abstract: A phase-field model that takes into account the bending energy of fluid vesicles is presented. The Canham-Helfrich model is derived in the sharp-interface limit. A dynamic equation for the phase-field has been solved numerically to find stationary shapes of vesicles with different topologies and the dynamic evolution towards them. The results are in agreement with those found by minimization of the Canham-Helfrich free energy. This fact shows that our phase-field model could be applied to more complex problems of instabilities.
Polymer-induced tubulation in lipid vesicles
F. Campelo,A. Hernandez-Machado
Quantitative Biology , 2008, DOI: 10.1103/PhysRevLett.100.158103
Abstract: A mechanism of extraction of tubular membranes from a lipid vesicle is presented. A concentration gradient of anchoring amphiphilic polymers generates tubes from bud-like vesicle protrusions. We explain this mechanism in the framework of the Canham-Helfrich model. The energy profile is analytically calculated and a tube with a fixed length, corresponding to an energy minimum, is obtained in a certain regime of parameters. Further, using a phase-field model, we corroborate these results numerically. We obtain the growth of tubes when a polymer source is added, and the bud-like shape after removal of the polymer source, in accordance with recent experimental results.
Model for curvature-driven pearling instability in membranes
F. Campelo,A. Hernandez-Machado
Quantitative Biology , 2007, DOI: 10.1103/PhysRevLett.99.088101
Abstract: A phase-field model for dealing with dynamic instabilities in membranes is presented. We use it to study curvature-driven pearling instability in vesicles induced by the anchorage of amphiphilic polymers on the membrane. Within this model, we obtain the morphological changes reported in recent experiments. The formation of a homogeneous pearled structure is achieved by consequent pearling of an initial cylindrical tube from the tip. For high enough concentration of anchors, we show theoretically that the homogeneous pearled shape is energetically less favorable than an inhomogeneous one, with a large sphere connected to an array of smaller spheres.
Improvements in the score matrix calculation method using parallel score estimating algorithm  [PDF]
Geraldo F. D. Zafalon, Evandro A. Marucci, Julio C. Momente, José R. A. Amazonas, Liria M. Sato, José M. Machado
Journal of Biophysical Chemistry (JBPC) , 2013, DOI: 10.4236/jbpc.2013.42006

The increasing amount of sequences stored in genomic databases has become unfeasible to the sequential analysis. Then, the parallel computing brought its power to the Bioinformatics through parallel algorithms to align and analyze the sequences, providing improvements mainly in the running time of these algorithms. In many situations, the parallel strategy contributes to reducing the computational complexity of the big problems. This work shows some results obtained by an implementation of a parallel score estimating technique for the score matrix calculation stage, which is the first stage of a progressive multiple sequence alignment. The performance and quality of the parallel score estimating are compared with the results of a dynamic programming approach also implemented in parallel. This comparison shows a significant reduction of running time. Moreover, the quality of the final alignment, using the new strategy, is analyzed and compared with the quality of the approach with dynamic programming.

Numerical-computational analysis of reinforced concrete structures considering the damage, fracture and failure criterion
Souza, L. A. F. de;Machado, R. D.;
Revista IBRACON de Estruturas e Materiais , 2013, DOI: 10.1590/S1983-41952013000100006
Abstract: the experimental results of testing structures or structural parts are limited and, sometimes, difficult to interpret. thus, the development of mathematical-numerical models is needed to complement the experimental analysis and allow the generalization of results for different structures and types of loading. this article makes two computational studies of reinforced concrete structures problems found in the literature, using the finite element method. in these analyses, the concrete is simulated with the damage classical model proposed by mazars and the steel by a bilinear elastoplastic constitutive model. numerical results show the validity of the application of constitutive models which consider the coupling of theories with the technique of finite element discretization in the simulation of linear and two-dimensional reinforced concrete structures.
Page 1 /556569
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.