6 documents found, page 1 of 1
Realistic Facial Three-Dimensional Reconstruction from CT Images and 2D Photogr...
Monteiro, Miguel; Vale, Francisco; Ferreira, Nuno C.; Marques, Filipa; Ribeiro, Madalena Prata; Santos, Mariana; Oliveira, Catarina; McEvoy, MarianaOrthognathic surgery is a procedure used to correct intermaxillary discrepancies, thus promoting significant improvements in chewing and breathing. During the surgical planning stage, orthodontists often use two-dimensional imaging techniques. The assessment is based on CBCT images and dental cast models to overcome these limitations; however, the evaluation of soft tissues remains complex. The aim of the prese...
An RPC-PET brain scanner demonstrator: first results
Fonte, Paulo; Lopes, Luís; Alves, Rui; Carolino, Nuno; Crespo, Paulo; Couceiro, Miguel; Cunha, Orlando; Dias, Nuno; Ferreira, Nuno C.; Fetal, SuseteWe present first results from a Positron Emission Tomography (PET) scanner demonstrator based on Resistive Plate Chambers and specialized for brain imaging. The device features a 30 cm wide cubic field-of-view and each detector comprises 40 gas gaps with 3D location of the interaction point of the photon. Besides other imagery, we show that the reconstructed image resolution, as evaluated by a hot-rod phantom, ...
The Warburg effect in mycobacterial granulomas is dependent on the recruitment ...
Appelberg, Rui; Moreira, Diana; Silva, Palmira Conceição Araújo Barreira; Borges, Margarida; Silva, Letícia; Dinis-Oliveira, Ricardo JorgeGranulomas are the hallmark of mycobacterial disease. Here, we demonstrate that both the cell recruitment and the increased glucose consumption in granulomatous infiltrates during Mycobacterium avium infection are highly dependent on interferon-y (IFN-y). Mycobacterium avium-infected mice lacking IFN-y signalling failed to developed significant inflammatory infiltrations and lacked the characteristic uptake of ...
RPC-PET: status and perspectives
Couceiro, M.; Blanco, A.; Ferreira, Nuno C.; Marques, R. Ferreira; Fonte, P.; Lopes, L.The status of the RPC-PET technology for small animals is briefly reviewed and its sensitivity performance for human PET studied through Monte-Carlo simulations. The cost-effectiveness of these detectors and their very good timing characteristics open the possibility to build affordable TOF-PET systems with very large fields of view. Simulations suggest that the sensitivity of such systems for human wholebody s...
Spatial resolution on a small animal RPC-PET prototype operating under magnetic...
Blanco, A.; Carolino, N.; Correia, C. M. B. A.; Fazendeiro, L.; Ferreira, Nuno C.; Marques, M. F. Ferreira; Marques, R. Ferreira; Fonte, P.; Gil, C.It has been demonstrated in previous work that the RPC-PET technology is able to deliver radioisotope image resolutions approaching the physical limits of the PET principle. Here we study, by simulation, the effect of the magnetic field on the positron range to evaluate whether the spatial resolution of the RPC-PET could be improved by using an intense magnetic field. Six positron emitters of interest to small ...
Very high position resolution gamma imaging with resistive plate chambers
Blanco, A.; Carolino, N.; Correia, C. M. B. A.; Fazendeiro, L.; Ferreira, Nuno C.; Marques, M. F. Ferreira; Marques, R. Ferreira; Fonte, P.; Gil, C.In this study we present experimental results from a first prototype of a positron emission tomography system based on the resistive plate chamber (RPC) technology. The system is composed of two counting heads, each one containing 16 single-gap RPC detectors capable of detecting the photon interaction point in the transaxial plane. Uniformity studies were performed for image resolution and sensitivity, yielding...