Patients with metastatic differentiated thyroid cancer (DTC) may be prepared using either thyroid-stimulating hormone withdrawal (THW) or recombinant human thyroid-stimulating hormone (rhTSH) injections before 131I administration for treatment. The objective of this study was to compare the absorbed dose to the critical organs and tumors determined by 124I PET/CT-based dosimetry for 131I therap...

Background: Annual patient effective dose equivalent can be considered as a quantitative physical parameter describing the activities performed in each nuclear medicine department. Annual staff dose equivalent could be also considered as a parameter describing the amount of radiation risk for performing the activities. We calculated the staff to patient dose equivalent ratio to be used as a phy...

We present synthesis models of the X–ray background where the available X–ray observational constraints are used to derive information on the AGN population properties. We show the need for luminous X–ray absorbed AGNs, the QSO2s, in reproducing the 2–10 keV source counts at relatively bright fluxes. We compare a model where the evolution of absorbed AGNs is faster than that of unabsorbed ones,...

A car-borne survey was carried out in the northwestern, or Tokatsu, area of Chiba Prefecture, Japan, to make a detailed distribution map of absorbed dose rate in air four years after the Fukushima Daiichi Nuclear Power Plant accident. This area was chosen because it was the most heavily radionuclide contaminated part of Chiba Prefecture and it neighbors metropolitan Tokyo. Measurements were per...

Earlier reports have shown that absorbed U4-labeled stearic (l), palmitic (2), and pentadecanoic (3) acids can be recovered, almost quantitatively, in intestinal or thoracic duct lymph. In the case of myristic acid, however, the highest recovery in lymph was about 80, and the lowest about 60 per cent of the absorbed C14. Still lower values (15 to 55 per cent) were observed with lauric acid, and...

One of the most important challenging factors in medical images is nominated as noise. Image denoising refers to the improvement of a digital medical image that has been infected by Additive White Gaussian Noise (AWGN). The digital medical image or video can be affected by different types of noises. They are impulse noise, Poisson noise and AWGN. Computed tomography (CT) images are subjects to ...

Previous studies have demonstrated an association between current hormone replacement therapy (HRT) use and increased mammographic breast density. Many of these studies have also shown that only 20-35% of women initiating HRT respond in this manner. This subgroup of HRT responders may be at an increased risk of breast cancer. We performed a case-control study to investigate how women who experi...

Many studies on biological effects of neutrons involve dose responses of neutrons, which rely on accurately determined absorbed doses in the irradiated cells or living organisms. Absorbed doses are difficult to measure, and are commonly surrogated with doses measured using separate detectors. The present work describes the determination of doses absorbed in the cell layer underneath a medium co...

This work investigated the suitability of passive dosimeters for reference dosimetry in small fields with acceptable accuracy. Absorbed dose to water rate was determined in nine small radiation fields with diameters between 4 and 35 mm in a Leksell Gamma Knife (LGK) and a modified linear accelerator (linac) for stereotactic radiosurgery treatments. Measurements were made using Gafchromic film (...