Comparison of space analysis performed on plaster vs. digital dental casts applying Tanaka and Johnston's equation

OBJETIVO: comparar medidas de tamanhos dentários, suas reprodutibilidades e a aplicação da equação de regressão de Tanaka e Johnston na predição do tamanho dos caninos e pré-molares em modelos de gesso e digital. MÉTODOS: trinta modelos de gesso foram escaneados para obtenção dos modelos digitais. As medidas do comprimento mesiodistal dos dentes foram obtidas com paquímetro digital nos modelos de gesso e nos modelos digitais utilizando o software O3d (Widialabs). A somatória do tamanho dos incisivos inferiores foi utilizada para obter os valores de predição do tamanho dos pré-molares e caninos utilizando equação de regressão, e esses valores foram comparados ao tamanho real dos dentes. Os dados foram analisados estatisticamente, aplicando-se aos resultados o teste de correlação de Pearson, a fórmula de Dahlberg, o teste t pareado e a análise de variância (p < 0,05). RESULTADOS: excelente concordância intraexaminador foi observada nas medidas realizadas em ambos os modelos. O erro aleatório não esteve presente nas medidas obtidas com paquímetro, e o erro sistemático foi mais frequente no modelo digital. A previsão de espaço obtida pela aplicação da equação de regressão foi maior que a somatória dos pré-molares e caninos presentes nos modelos de gesso e nos modelos digitais. CONCLUSÃO: apesar da boa reprodutibilidade das medidas realizadas em ambos os modelos, a maioria das medidas dos modelos digitais foram superiores às do modelos de gesso. O espaço previsto foi superestimado em ambos os modelos e significativamente maior nos modelos digitais.

A comparison of the allometric growth in Uca leptodactyla (Crustacea : Brachyura : Ocypodidae) from two subtropical estuaries

The allometric growth of Uca leptodacyla from two distinct subtropical estuaries on the Brazilian coast was evaluated concerning its growth pattern and size at onset of sexual maturity. Females attained maturity at similar sizes in both sites (4.1 mm of carapace length in Indaia and 4.2 mm in Ubatumirim), while males differed slightly. They reached the size at sexual maturity of 5.3 mm of carapace length in Indaia and 4.6 mm in Ubatumirim. Growth pattern is Usually similar among crabs from distinct Sites while size at sexual maturity is frequently different. However, in the case of U. leptodacyla it did not occur, probably due to the strong habitat similarity and intrinsic features of this species.

Allometry of the secondary sexual characters of the shore crab Pachygrapsus transversus (Gibbes, 1850) (Brachyura, Grapsidae)

The allometric growth of secondary sexual characters in Pachygrapsus transversus is investigated from the 2(nd) crab stage onward. Clear sexual dimorphism is restricted to abdominal morphology, but ANCOVA analyses showed that chelae become larger in males and the carapace becomes wider in females. Size at the puberty moult in both sexes was estimated using Somerton's computer techniques. Mature II analyses applied to bi-log gonopod length vs, carapace length relationships indicated a puberty moult at 5.0 mm in males.In females, Mature I analyses detected the overlapping growth phase lines in bi-log carapace length vs. abdomen width scatterplots. Fitting the logistic equation provided an estimate of 50% maturity at 5.5 mm. The regression lines separate young and resting individuals from the potentially reproductive females, but they do not separate young from adult crabs. Year-round monthly samples showed that the proportion of small adult-like females is higher during the breeding season. After breeding, females may moult to a young-like morphotype, as observed in controlled laboratory conditions. Moulting to a resting condition splits smaller mature females into different growth phase lines. Therefore, estimates of female size at sexual maturity by means of abdomen allometric growth analyses are inadequate in this species.

A morphometric study of the mud crab, Panopeus austrobesus Williams, 1983 (Decapoda, Brachyura) from a subtropical mangrove in South America

The relative growth of the xanthid crab, Panopeus austrobesus was investigated by means of the allometric method. Crabs were obtained in the mangrove formed by the estuary of the rivers Comprido and Escuro (23degrees29'24S 45degrees10'12W), Ubatuba, São Paulo State, Brazil. All crabs were measured to obtain their carapace width (CW) and length (CL), abdomen width (AW) at the basis of the 5(th) somite, and major cheliped propodus length (PL) and height (PH). Males were also measured for their gonopod length (GL). The size of crabs based on CW ranged from 4.0 to 44.8 mm for males and 3.1 to 34.5 mm for females. The relative growth equation (Y = aX(b)) based on the relationship between GL and CW suggested that males reach their sexual maturity near 14.6 mm CW. Such relationship shows a positive allometry during the juvenile phase and an isometric growth in adult life. In females, the estimated size at 50% maturity is 13.0 mm CW, based on the relationship AW vs. CW. Males reach larger sizes than females, which probably provides them better conditions to protect females during courtship. Concerning cheliped size, approximately 73% of the crabs analysed (N = 209), disregarding sex, have the right PL larger than the left. The PL growth shows that specimens with a left major cheliped (26%) have a higher allometric coefficient, despite being smaller considering their CW. Such a difference may compensate the smaller size of the crab during defense or prey capture.

Morphometry of the crab Hexapanopeus schmitti (Decapoda : Xanthoidea) on the northern coast of the state of São Paulo, Brazil

A morphometric study of the xanthoid crab Hexapanopeus schmitti was carried out, using the allometric method. Samples were taken monthly for two years (1998-1999) in the Ubatuba region, northern coast of São Paulo, Brazil. Sex and size were assessed for each specimen, and all crabs were measured to obtain their carapace width (CW) and length (CL), abdomen width (AW) of females, major cheliped propodus length and height (PL and PH), and gonopod length (GL) of males. A total of 301 crabs were analyzed, 209 males and 92 females. The CWs of the crabs ranged from 2.5 to 9.8 mm for males and from 2.8 to 9.4 mm for females. The relative growth equation (y=ax(b)) based on the relationship between GL and CW suggested that males reach their morphological sexual maturity near 6.1 mm CW. In females, the estimated size at 50 % maturity was 4.8 mm CW, based on the relationship of AW vs. CW. Males reach larger sizes than females, which probably favors their ability to guard the females during courtship. In approximately 83 % of the crabs (n= 371), disregarding sex, the right cheliped was larger.

MATHEMATICA notebook for computing tetrahedral finite element shape functions and matrices for the Helmholtz equation

A MATHEMATICA notebook to compute the elements of the matrices which arise in the solution of the Helmholtz equation by the finite element method (nodal approximation) for tetrahedral elements of any approximation order is presented. The results of the notebook enable a fast computational implementation of finite element codes for high order simplex 3D elements reducing the overheads due to implementation and test of the complex mathematical expressions obtained from the analytical integrations. These matrices can be used in a large number of applications related to physical phenomena described by the Poisson, Laplace and Schrodinger equations with anisotropic physical properties.

Edge detection and noise removal by use of a partial differential equation with automatic selection of parameters

This work deals with noise removal by the use of an edge preserving method whose parameters are automatically estimated, for any application, by simply providing information about the standard deviation noise level we wish to eliminate. The desired noiseless image u(x), in a Partial Differential Equation based model, can be viewed as the solution of an evolutionary differential equation u t(x) = F(u xx, u x, u, x, t) which means that the true solution will be reached when t ® ¥. In practical applications we should stop the time ''t'' at some moment during this evolutionary process. This work presents a sufficient condition, related to time t and to the standard deviation s of the noise we desire to remove, which gives a constant T such that u(x, T) is a good approximation of u(x). The approach here focused on edge preservation during the noise elimination process as its main characteristic. The balance between edge points and interior points is carried out by a function g which depends on the initial noisy image u(x, t0), the standard deviation of the noise we want to eliminate and a constant k. The k parameter estimation is also presented in this work therefore making, the proposed model automatic. The model's feasibility and the choice of the optimal time scale is evident through out the various experimental results.

A Decomposition and Noise Removal Method Combining Diffusion Equation and Wave Atoms for Textured Images

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

Solutions of the Fokker-Planck equation for a Morse isospectral potential

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A General Solution of the Fokker-Planck Equation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Particular solution for anomalous diffusion equation with source term

In literature the phenomenon of diffusion has been widely studied, however for nonextensive systems which are governed by a nonlinear stochastic dynamic, there are a few soluble models. The purpose of this study is to present the solution of the nonlinear Fokker-Planck equation for a model of potential with barrier considering a term of absorption. Systems of this nature can be observed in various chemical or biological processes and their solution enriches the studies of existing nonextensive systems.

Discussion on the limit cycles of the Lev Ginzburg equation by M. Bellamy and R.E. Mickens, Journal of Sound and Vibration 308 (2007) 337-342

The authors M. Bellamy and R.E. Mickens in the article "Hopf bifurcation analysis of the Lev Ginzburg equation" published in Journal of Sound and Vibration 308 (2007) 337-342, claimed that this differential equation in the plane can exhibit a limit cycle. Here we prove that the Lev Ginzburg differential equation has no limit cycles. (C) 2012 Elsevier Ltd. All rights reserved.

Global dynamics of stationary solutions of the extended Fisher-Kolmogorov equation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Vortices in nonlocal Gross-Pitaevskii equation

We consider vortices in the nonlocal two-dimensional Gross-Pitaevskii equation with the interaction potential having Lorentz-shaped dependence on the relative momentum. It is shown that in the Fourier series expansion with respect to the polar angle, the unstable modes of the axial n-fold vortex have orbital numbers l satisfying 0 < \l\ < 2\n\, as in the local model. Numerical simulations show that nonlocality slightly decreases the threshold rotation frequency above which the nonvortex state ceases to be the global energy minimum and decreases the frequency of the anomalous mode of the 1-vortex. In the case of higher axial vortices, nonlocality leads to instability against splitting with the creation of antivortices and gives rise to additional anomalous modes with higher orbital numbers. Despite new instability channels with the creation of antivortices, for a stationary solution comprised of vortices and antivortices there always exists another vortex solution, composed solely of vortices, with the same total vorticity but with a lower energy.

Relaxation algorithm to hyperbolic states in Gross-Pitaevskii equation

A new version of the relaxation algorithm is proposed in order to obtain the stationary ground-state solutions of nonlinear Schrodinger-type equations, including the hyperbolic solutions. In a first example, the method is applied to the three-dimensional Gross-Pitaevskii equation, describing a condensed atomic system with attractive two-body interaction in a non-symmetrical trap, to obtain results for the unstable branch. Next, the approach is also shown to be very reliable and easy to be implemented in a non-symmetrical case that we have bifurcation, with nonlinear cubic and quintic terms. (c) 2006 Elsevier B.V. All rights reserved.