Background: Attenuation coefficient (μ) plays an important role in calculations of treatment planning systems, as well as determination of dose distributions in external beam therapy, dosimetry, protection, phantom materials and industry. So, its exact measurement or calculation is very important. The aim of this study was to evaluate the μ in different points in the water phantom anal...

BACKGROUND Measurements of parameters from electrocardiograms (ECGs) are still largely performed from paper ECG records. Recent guidelines from regulatory agencies and, in particular, the requirement of the Food and Drug Administration to enforce the digital submission of annotated ECGs have triggered significant efforts in the pharmaceutical industry, which, to comply with the new guidelines, ...

Chromatic discrimination thresholds were measured under conditions which yielded fine and degraded discrimination steps. Discrimination was assessed by identification of the location of one of four homogeneous equiluminant stimuli arranged in a square or with pseudoisochromatic (PIC) figures using the stimulus design of Regan, Reffin and Mollon (Vis Res 1994; 34: 1279-1299). Stimuli were presen...

Introduction: Nowadays,  considerable developments  in  the field  of  radiotherapy have  been  achieved.  They  include  the  advances  made  in  the  equipments  and  treatment  planning  techniques  which  require  highly complex calculations. Such achievements have made it possible to treat cancer patients not only  with  higher  radiation  dose  but  also  with  higher  precision  and  con...

A two-dimensional photonic-crystal engineered to possess a refractive index equal to minus one at a certain frequency is used as a flat superlens. Subwavelength imaging (image size below half a wavelength) is observed both in the near-field and far-field regimes when the interface with air is properly terminated to support surface states with even

—Several studies have reported that some grassland birds are area sensitive; they exhibit a nonrandom avoidance of small fields. The methods used to test for area sensitivity, however, differed among studies. Some investigators sampled fields with sampling effort proportional to field size, whereas others used equal sampling effort in all fields. We created a simulation model with the same numb...

We consider a particular case of the two dimensional BlumeEmery-Griffiths model to study the finite-size scaling for a field driven first-order phase transition with two coexisting phases not related by a symmetry. For low temperatures we verify the asymptotic (large volume) predictions of the rigorous theory of Borgs and Kotecký, including the predictions concerning the so-called equal-weight ...