How do selective and constructive visual mechanisms interact to determine the outcome of conscious perception? Binocular rivalry involves selective perception of one of two competing monocular images, whereas visual phantoms involve perceptual filling-in between two low-contrast collinear gratings. Recently, we showed that visual phantoms lead to neural filling-in of activity in V1 and V2, whic...

This paper deals with the CT scanner images quality control, which is an important part of the quality control process of the CT scanner, which consists of making measurement in images of dedicated phantoms. Standard methods consist of scan explorations of phantoms that contain different specific patterns . These methods rely on manual measurements with graphics tools in corresponding images (d...

Optical devices for measuring protoporphryin IX (PpIX) fluorescence in tissue are routinely validated by measurements in optical phantoms. Yet there exists limited data to form a consensus on the recipe for phantoms that both mimic the optical properties found in tissue and yield a reliable and stable relationship between PpIX concentration and the fluorescence remission intensity. This study c...

Various models of anthropomorphic phantoms have been developed in the past decades for usage in Monte Carlo simulation for radiation protection and other medical physics applications; they adopt two alternative approaches, either modelling the body components through analytical geometrical representations or through voxelized geometries. An original system has been developed associated with the...

introduction the purpose of the current study was to determine optical sensitivity of n-isopropyl acrylamide nipam and polyacrylamide gelatin and tetrakis hydroxymethyl phosphoniun chloride (pagat) polymer gels for different wavelength of visible light spectrum applied in optical computed tomography method. materials and methods nipam and pagat polymer gels with conventional formulations used f...

Tissue simulating phantoms can provide a valuable platform for quantitative evaluation of the performance of diffuse optical devices. While solid phantoms have been developed for applications related to characterizing exogenous fluorescence and intrinsic chromophores such as hemoglobin and melanin, we report the development of a poly(dimethylsiloxane) (PDMS) tissue phantom that mimics the spect...

Introduction Based on Task Group No. 43 (TG-43U1) recommendations, water phantom is proposed as a reference phantom for the dosimetry of brachytherapy sources. The experimental determination of TG-43 parameters is usually performed in water-equivalent solid phantoms. The purpose of this study was to determine the conversion factors for equalizing solid phantoms to water. Materials and Methods T...

We report on a non-contact method to quantitatively determine blood volume fractions in turbid media by reflectance spectroscopy in the VIS/NIR spectral wavelength range. This method will be used for spectral analysis of tissue with large absorption coefficients and assist in age determination of bruises and bloodstains. First, a phantom set was constructed to determine the effective photon pat...

Background and Objectives: Making stacking gels for polyacrylamide gels in the laboratory by conventional methods is laborious and time consuming. Considering the role of temperature in polyacrylamide gels with respect to electrical resistance and viscosity, we assumed that decreasing the temperature would cause an increase in electrical resistance and viscosity.  Ultimately, a downward tempera...