Programação linear no planejamento do tratamento de câncer por radiocirurgia

Medical Physics has been reaching an important role among several lines in Science, providing means for the improvement of several theories and procedures. Currently, its main application is related with the use of ionizing radiations, specially, in treatment procedures such as Radiotherapy. Radiosurgery is a Radiotherapy technique which consists in administering a single tumoricidal dose of radiation exclusively to the tumorous lesion. It becomes then an interesting alternative to surgical treatment, mainly in cerebral metastases, which are the most frequent cerebral tumors in the central nervous system. The radio neurosurgical team works out a planning for the Radiosurgery treatment, aiming for obtaining an appropriate ideal treatment for each case. For the working out of this treatment planning, Computed Tomography images of the region to be treated are obtained, digitalized and later, fused with nuclear magnetic resonance images. Through these images, critical structures, organs at risk and lesions are localized. After this, calculations are made to determine three-dimensional positions of isocenters, isodose curves, prescribed dose, collimators sizes, position, numbers and respective weight of isocentric conformal fields, and others. The treatment planning is commonly based in desired levels of dose for specific types of tumors and organs at risk concerning the irradiated region. Theses levels of dose are chosen in a way that a high probability of cure may be achieved and meanwhile, that the probability of complications, in whichever organ at risk, may be minimal. Thus, many researches have been carried out, showing that mathematical techniques may help to obtain an optimal planning for the treatment of cerebral metastases. Among the methods of optimization in the study...(Complete abstract click electronic access below)

Estudo para correção dos sensores da rede de monitoramento do campo elétrico em função do campo elétrico de tempo bom

A monitoring network of atmospheric electric field covering the Vale do Paraiba region was implemented. The sensors were located on different sites with different altitude and geographic topology. The present work reports the study carried on those sensors in order to verify the necessity of using some correction factor to the measured local electric field intensity due to effects of local environment. The measurements were done in continuous 24 hours per day with the data recorded on registers in each device accumulating information during a period of four months. The relation between the electric field values by each sensor was compared to the reference located on Sao Jose dos Campos city using the same period. In a graphical analysis using the local field intensity and the reference, the data were fitted to a straight line obtained by minimum square method. Variation up to 95% was observed between the field values in some sensors. Another method was proposed, comparing the mean values of the electric field in a function of time. The variation in some sensors reached up to 133%. We conclude that the variations are due to local atmospheric conditions and no correction factor is required on the electric field sensors

Análise de Tópicos Relevantes em Programação Linear e Aplicações no Ensino de Engenharia

Pós-graduação em Engenharia Elétrica - FEIS

Equação de Schrödinger não linear com coeficientes modulados

Pós-graduação em Física - FEG

Influência dos polimorfismos Taql e Bsml do gene do receptor de vitamina D no surgimento de infecção, tempo de internação e mortalidade em pacientes queimados

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Fibra para cães: efeitos sobre o processo de extrusão, digestibilidade, fermentação microbiana, tempo de retenção intestinal e palatabilidade de rações para cães

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação da qualidade térmica de espaços de transição do tipo linear externo

Pós-graduação em Arquitetura e Urbanismo - FAAC