DE SITTER TRANSITIVITY, CONFORMAL TRANSFORMATIONS AND CONSERVATION LAWS

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

Teorema de Pitágoras: algumas extensões/generalizações e atividades com o Software GeoGebra

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo de órbitas periódicas em equações diferenciais não autônomas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Involutive constrained systems and Hamilton-Jacobi formalism

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

C-l-contact and C-l-right equivalences of real semi-quasihomogeneous C-l function germs

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

SPECT (Single photon emission tomography): Gama câmara, reconstrução tomográfica e características funcional

The SPECT (Single Photon Emission Computed Tomography) systems are part of a medical image acquisition technology which has been outstanding, because the resultant images are functional images complementary to those that give anatomic information, such as X-Ray CT, presenting a high diagnostic value. These equipments acquire, in a non-invasive way, images from the interior of the human body through tomographic mapping of radioactive material administered to the patient. The SPECT systems are based on the Gamma Camera detection system, and one of them being set on a rotational gantry is enough to obtain the necessary data for a tomographic image. The images obtained from the SPECT system consist in a group of flat images that describe the radioactive distribution on the patient. The trans-axial cuts are obtained from the tomographic reconstruction techniques. There are analytic and iterative methods to obtain the tomographic reconstruction. The analytic methods are based on the Fourier Cut Theorem (FCT), while the iterative methods search for numeric solutions to solve the equations from the projections. Within the analytic methods, the filtered backprojection (FBP) method maybe is the simplest of all the tomographic reconstruction techniques. This paper's goal is to present the operation of the SPECT system, the Gamma Camera detection system, some tomographic reconstruction techniques and the requisites for the implementation of this system in a Nuclear Medicine service

Sobre o teorema de fibração de Milnor

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Teorema de Riemann-Roch, morfismos de Frobenius e a hipótese de Riemann

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

Existência de soluções para equações integrodiferenciais em epaços de Banach

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Algumas generalizações do teorema clássico de Borsuk-Ulam

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Área e volume: a transição da noção de medida à de área e de volume

Pós-graduação em Matemática em Rede Nacional - IBILCE

O Teorema de Pitágoras: alternativas de demonstrações

Pós-graduação em Matemática em Rede Nacional - IBILCE

Fields of two power conductor

The goal of this work is find a description for fields of two power conductor. By the Kronecker-Weber theorem, these amounts to find the subfields of cyclotomic field $\mathbb{Q}(\xi_{2^r})$, where $\xi_{2^r}$ is a $2^r$-th primitive root of unit and $r$ a positive integer. In this case, the cyclotomic extension isn't cyclic, however its Galois group is generated by two elements and the subfield can be expressed by $\mathbb{Q}(\theta)$ for a $\theta\in\mathbb{Q}(\xi_{2^r})$ convenient.

A simple observation concerning contraction mappings

In this short note we show that the results obtained by Walter in [4] remain valid if we change the metric by another metric. Furthermore, if we use the norm jjT; given in [3], Theorem B in[4] remains valid.

Some Results in Stability Analysis of Hybrid Dynamical Systems

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)