Reduced calibration curve for proton computed tomography

The pCT deals with relatively thick targets like the human head or trunk. Thus, the fidelity of pCT as a tool for proton therapy planning depends on the accuracy of physical formulas used for proton interaction with thick absorbers. Although the actual overall accuracy of the proton stopping power in the Bethe-Bloch domain is about 1%, the analytical calculations and the Monte Carlo simulations with codes like TRIM/SRIM, MCNPX and GEANT4 do not agreed with each other. A tentative to validate the codes against experimental data for thick absorbers bring some difficulties: only a few data is available and the existing data sets have been acquired at different initial proton energies, and for different absorber materials. In this work we compare the results of our Monte Carlo simulations with existing experimental data in terms of reduced calibration curve, i.e. the range - energy dependence normalized on the range scale by the full projected CSDA range for given initial proton energy in a given material, taken from the NIST PSTAR database, and on the final proton energy scale - by the given initial energy of protons. This approach is almost energy and material independent. The results of our analysis are important for pCT development because the contradictions observed at arbitrary low initial proton energies could be easily scaled now to typical pCT energies. © 2010 American Institute of Physics.

Comparison of the GEANT4 releases 8.2 and 9.2 in terms of a pCT reduced calibration curve

The GEANT4 simulations are essential for the development of medical tomography with proton beams pCT. In the case of thin absorbers the latest releases of GEANT4 generate very similar final spectra which agree well with the results of other popular Monte Carlo codes like TRIM/SRIM, or MCNPX. For thick absorbers, however, the disagreements became evident. In a part, these disagreements are due to the known contradictions in the NIST PSTAR and SRIM reference data. Therefore, it is interesting to compare the GEANT4 results with each other, with experiment, and with diverse code results in a reduced form, which is free from this kind of doubts. In this work such comparison is done within the Reduced Calibration Curve concept elaborated for the proton beam tomography. © 2010 IEEE.

De platon à candido: la littérature en question

Cette étude propose, à partir de quelques conceptions de littérature qui circulent dans le domaine de la critique littéraire, une approche théorico-critique. Pour ce faire, on partira de la vision platonicienne et aristotélicienne, pour ensuite discuter les contradictions observables dans les concepts mêmes de littérature. A la fin, on se décidera pour une conception spécifique, en raison de sa flexibilité.

Recidiva Neural em hanseníase multibacilar após 6 anos de tratamento

This article presents a case of relapse, with isolated neural manifestation, in a multibacillary patient previously treated with multidrug therapy for multibacillary leprosy (24 doses). The patient returned to the service six years after the end of treatment, with pain in hands and legs. He was investigated, and the serological monitoring showed an important increase in anti-phenolic glycolipid serum levels. A neural recurrence was suspected, since the patient had no new skin lesions. A new biopsy in the right ulnar nerve showed a bacilloscopy of 2 +, compatible with relapse. This is a literature review of the etiological, clinical, propedeutical and diagnostic aspects of this situation so poorly understood. © 2012 by Anais Brasileiros de Dermatologia.

Arte pública: fundamentos do discurso público da Arte

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência do treinamento físico de alta intensidade sobre o metabolismo de ratos espontaneamente hipertensos (SHR)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Sistemática molecular de Atta laevigata (Smith 1858) e Acromyrmex balzani (Emery 1890)

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

Estudo de cepas de Staphylococcus aureus isoladas de amostras nasais e linguais de portadores voluntários adultos saudáveis

Pós-graduação em Biociências e Biotecnologia Aplicadas à Farmácia - FCFAR

Acúmulo de saberes e experiência formativa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Suco de laranja reduz colesterol e insulina no sangue de indivíduos saudáveis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O Estado no sistema sociometabólico do capital: uma relação de complementaridade na base material

Pós-graduação em Ciências Sociais - FFC

Luta de classes na cidade neoliberal: uma análise sobre o Movimento dos Trabalhadores Sem Teto

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Os descaminhos da estrada: a organização do trabalho dos caminhoneiros no porto de Santos

Pós-graduação em Ciências Sociais - FFC

Para além dos muros e das grades: atitudes e valores em relação às instituições carcerárias do município de Valparaíso/SP

Pós-graduação em Ciências Sociais - FFC

A questão da reforma agrária e do agronegócio, sob o aspecto da produtividade -: o caso da região de Ribeirão Preto-SP

Pós-graduação em Ciências Sociais - FCLAR