... Accession Number : AD0672563. Title : A CALORIMETER WITH INTERCHANGEABLE ABSORBERS FOR ABSORBED DOSE ...
DTIC Science & Technology
... Title : MODELS FOR ESTIMATING THE ABSORBED DOSE FROM ASSIMILATION OF RADIONUCLIDES IN BODY ORGANS OF HUMANS,. ...
According to published data, the absorbed dose used for a CBCT image acquisition with Varian OBI v1.3 can be as high as 100 mGy. In 2008 Varian released a new OBI version (v1.4), which promised to reduce the imaging dose. In this study, absorbed doses used for CBCT image acquisitions with the ...
PubMed
Absorbed-dose images and depth-dose profiles have been measured in a tissue-equivalent phantom exposed to an epithermal neutron beam designed for neutron capture therapy. The spatial distribution of absorbed dose has been measured by means of gel dosimeters, imaged with optical analysis. From ...
Energy Citations Database
NASA Astrophysics Data System (ADS)
The absorbed dose primary standard of the BEV is a graphite calorimeter. Two methods are employed for the conversion of absorbed dose to graphite into absorbed dose to water: calculation on the one hand and the use of an ionization chamber in combination ...
National Technical Information Service (NTIS)
The threshold values of total absorbed dose for causing changes in tensile properties of a polyetherimide film and the limitations of the absorbed dose rate for accelerated-exposure evaluation of the effects of electron radiation in geosynchronous orbit w...
Absorbed dose and dose equivalent from negatively and positively charged pions in energy range 10 to
NASA Technical Reports Server (NTRS)
... Title : A FORTRAN PROGRAM TO DETERMINE ABSORBED ORGAN DOSE DUE TO INHALATION OF RADIONUCLIDES,. ...
... of absorbed dose; rem relates the absorbed dose in human tissue to the ... effort to increase the nation's preparedness for potential attacks against ...
... Title : Computational Determination of Absorbed Dose Distributions From Multiple Volumetric Gamma Ray Sources,. Corporate Author : ...
The concepts of radiation exposure dose, absorbed dose, and biological dose resulting from ionizing particles are reviewed. The units used in radiation measurements are defined, and the concept of electronic equilibrium is discussed. The Bragg-Gray cavity relation ls used to calculate the ...
Using a semi-empirical electron transport model and the solution of the one-group S>2 transport equation for a multilayered system, we have developed a fast algorithm for calculating X-ray dose enhancement in device structures. The program MULTILAYER, written in BASIC for an IBM-PC compatible microcomputer, calculates (1) the dose ...
... MINUTE INVESTIGATION OF ABSORBED DOSES IN COMPLEX ... DESCRIBED OF SUCH A DETERMINATION. ... CASE OF DOSE DISTRIBUTION AT ...
The feasibility of this calorimeter is mainly the result of the low thermal diffusivity of water that retards a temperature change at a point along a temperature profile. The temperature change is sensed by two calibrated thermistors sandwiched between two polyethylene films that electrically insulate the thermistors from water. The product of the temperature rise and the ...
Based on the determination of protons fluence at the phantom's surface, a 3D dose distribution is calculated inside a water phantom using a fast method. The dose contribution of secondary particles, originating from inelastic nuclear interactions, is also taken into account. This is achieved by assuming that 60% of the energy transferred to secondary ...
Medical Internal Radiation Dose(MIRD) schema was developed for calculating the absorbed dose from the administrated radiopharmaceuticals. With the biological distribution data and physical properties of the radionuclide, we can estimated the absorbed dose...
... Abstract : The effects of electron radiation on Ultem, a ... were studied for total absorbed doses from 1.0 kGy to 100 MGy at absorbed dose rates from ...
... Abstract : ;Contents: Interaction between radiation and tissue; Radiation quantities and units; Radiation quality and dose equivalent; History of dose ...
... EQUIVALENTS OF GALACTIC RADIATION EXPOSURE IN SPACE,. ... In assessing the astronaut's exposure from galactic ... of absorbed doses to dose ...
... AS INDICATORS OF ABSORBED RADIATION DOSE IN RATS. ... of doses of mixed gamma-neutron radiations or 14 ... was a function of dose over the ...
From the beginning of the neutron therapy program at the University of Washington Medical Center, the neutron dose distribution in tissue has been calculated using an in-house treatment planning system called PRISM. In order to increase the accuracy of the absorbed dose calculations, two main improvements were made to the PRISM ...
ObjectiveThe objectives of the study were to determine the absolute bioavailability of fentanyl from fentanyl buccal soluble film, estimate the percentage of a fentanyl dose absorbed through the buccal mucosa, and compare the bioavailability of equivalent doses administered either as single or multiple dose ...
PubMed Central
The absorbed dose in BNCT (boron neutron capture therapy) consists of several radiation components with different physical properties and biological effectiveness. In order to assess the clinical efficacy of the beams, determining the dose profiles in tissues, Monte Carlo (MC) simulations are used. This paper ...
... Title : Radiation Energy Absorbed by Human Phantoms ... DOSIMETERS, INSTRUMENTATION, IONIZATION CHAMBERS, DOSE RATE, RADIATION ...
This report describes methods and computer programs for calculating absorbed-dose distribution in a water target irradiated by proton beams. The spatial pattern of absorbed dose from monoenergetic pencil beams is calculated as a function of the depth in t...
Values of the fast neutron absorbed dose rate in an ethylene absorber are given as a function of penetration distance in hydrogen. The dose rates were obtained by numerical integration of the product of the differential number spectrum and the ethylene conversion factors. (auth)
The conversion of absorbed doses in graphite to absorbed doses in water was studied. A method employing a thin walled ionization chamber as a transfer device was developed. A commercial secondary standard therapy level exposure meter was used in one of th...
At present, absorbed dose calculations for radionuclides in the human circulatory system used relatively simple models and are restricted in their applications. To determine absorbed doses to the blood and to the surface of the blood vessel wall, EGS4 Mon...
The measurement of absorbed dose as well as dose distributions (profiles and isodose curves) for small radiation fields (as encountered in stereotactic surgery) has been difficult due to the usual large detector size or densitometer aperture (> 1 mm) relative to the radiation field (as small as 4 mm). The ...
A technique is presented for calculating the dose or energy absorbed in a material from a knowledge of the ..gamma.. radiation field and the composition of the material. The absorbed dose per unit exposure for various elements and the absorbed dose as a function of material ...
The treatment of uveal melanoma with proton radiotherapy has provided excellent clinical outcomes. However, contemporary treatment planning systems use simplistic dose algorithms that limit the accuracy of relative dose distributions. Further, absolute predictions of absorbed dose per monitor unit are not yet ...
The fate of selected polychlorobiphenyls (PCBs) was investigated following single dermal administration (0.4 mg/kg) to determine the effects of chlorine content and position on the disposition of PCBs following dermal absorption. Single dermal doses of {sup 14}C-labeled mono-, di-, tetra- and hexachlorobiphenyls were administered to 1 cm{sup 2} areas on the backs of F-344 male ...
... dose, Q is the quality factor, and N is the product of any other modifying factors such as those accounting for effects due to dose rate, dose ...
Apr 21, 2011 ... Data Set Name, Crew Absorbed Doses from Passive Dosimeters ... This table shows a comparison of absorbed doses from TLD passive dosimeters. ...
NASA Website
... dosimeters for X rays in the 1�50 MeV range be calibrated in terms of absorbed dose to ... ...
NBII National Biological Information Infrastructure
Read out the absorbance of a dosimetric foil is accomplished by two beam spectrophotometer. Such a solution makes possible the compensation of light source instabilities and ensures higher stability of the dose reader. The error of absorbance measurement ...
... In dosimetry, the absorbed dose is defined as the amount of energy absorbed per unit mass of the material. ... 10 Protons 10 Alpha particles 10 ...
... on a cellular level using tissue-equivalent scintillation techniques ... first phase of the development of a Cellular Absorbed Dose Spectrometer (CADS ...
Four tables designed to permit rapid conversion from one to another of the units for absorbed dose, absorbed dose rate, energy, and power are given. (M.C.G.)
... Accession Number : ADD344981. Title : Computational Determination of Absorbed Dose Distribution From Gamma Ray Sources,. Corporate Author ...
The objective of this paper is to critically evaluate the interrelationship of the radiopharmaceuticals, radionuclides and organ visualization instrumentation on the resultant absorbed dose to a patient having a bone scan versus the clinical information o...
Administration of x-ray contrast agents during heart catheterization examination increases the absorbed radiation dose in tissue. To estimate the dose absorbed by the blood of children undergoing diagnostic heart catheterization and angiocardiography, a number of measurements and calculations were conducted ...
The dose from a semi-infinite cloud of a photon-emitting radionuclide is an idealization of an exposure situation, but it is a useful one, particularly for noble gases of long radioactive decay haif-times, e.g. /sup 85/Kr. An analysis is presented of absorbed dose to body organs for monoenergetic photons emitted in an ...
... necessary for absorbed radiation dose estimates, as ... SUBSTANCES, *RADIOACTIVE ISOTOPES, *RADIATION DOSAGE, *DIAGNOSTIC AGENTS ...
... Additional work is required relating resistance change for these materials to absorbed ribbon dose, and determination of the maximum dose for ...
nonuniform dose distributions resulting from flare proton spectra leads to the assignment of the absorbed dose at 4- ...
Our study was performed in the context of an in vitro primary hepatic cell culture as an alternative for the in vivo cancerogenic bioassay. The 29 substances which are to be used in the in vitro primary hepatic cell culture have been tested in 2-year bioassays and a 14-day short term study. The aim of this modelling study was to simulate the concentration--time profile of the ...
The introduction of a biophysical quantity, the biological dose, is proposed, which is defined in terms of the absorbed dose and the relative biological effectiveness. The unit of the biological dose is the rem, while the unit of the absorbed dose is the rad. The ...
Cellular, animal, and human radiobiology studies are in progress at the Los Alamos Meson Physics Facility as part of a joint University of New Mexico and Los Alamos Scientific Laboratory pion therapy project. To support these activities, dosimetry has been performed on many different pion beam configurations. The effect of both static and dynamic momentum spreaders and of collimators on beam ...
The threshold values of total absorbed dose for causing changes in tensile properties of a polyetherimide film and the limitations of the absorbed dose rate for accelerated-exposure evaluation of the effects of electron radiation in geosynchronous orbit were studied. Total absorbed ...
The absorbed dose in a material near a boundary with a dissimilar material may differ considerably from the dose in the bulk material. The peak dose near the interface can be more than a factor of ten greater than the bulk dose. The dose distribution is d...
Concrete examples are used to show the easy way of calculating the integral absorbed dose in radiotherapy, radiography, and also in curietherapy. The knowledge of this integral absorbed dose enables the less dangerous to be chosen for the patient among two irradiation techniques. The integral ...
