TY - JOUR. T1 - Integration of new biological and physical retrospective dosimetry methods into EU emergency response plans-joint RENEB and EURADOS inter-laboratory comparisons. AU - Ainsbury, Elizabeth. AU - Badie, Christophe. AU - Barnard, Stephen. AU - Manning, Grainne. AU - Moquet, Jayne. AU - Abend, Michael. AU - Antunes, Ana Catarina. AU - Barrios, Lleonard. AU - Bassinet, Celine. AU - Beinke, Christina. AU - Bortolin, Emanuela. AU - Bossin, Lily. AU - Bricknell, Clare. AU - Brzoska, Kamil. AU - Buraczewska, Iwona. AU - Castaño, Carlos Huertas. AU - Čemusová, Zina. AU - Christiansson, Maria. AU - Cordero, Santiago Mateos. AU - Cosler, Guillaume. AU - Monaca, Sara Della. AU - Desangles, François. AU - Discher, Michael. AU - Dominguez, Inmaculada. AU - Doucha-Senf, Sven. AU - Eakins, Jon. AU - Fattibene, Paola. AU - Filippi, Silvia. AU - Frenzel, Monika. AU - Georgieva, Dimka. AU - Gregoire, Eric. AU - Guogyte, Kamile. AU - Hadjidekova, Valeria. AU - Hadjiiska, Ljubomira. AU - Hristova, ...

There is provided a superconducting radiometry apparatus capable of performing, while sample-measuring, an energy correction in regard to a fluctuation of a peak value of an output signal, which is due to a radiation heat and a magnetic field from an outside. The superconducting radiometry apparatus is constituted by comprising a micro-calorie meter detecting an energy of a radiant ray as a temperature change, a signal detection mechanism for detecting a displacement of an electric current flowing to the micro-calorie meter, a shunt resistance which is connected in parallel to the micro-calorie meter and whose resistance value is smaller than the micro-calorie meter, a bias electric source connected to the micro-calorie meter and the shunt resistance and applying a constant voltage, a heat addition device adding a constant and already-known heat quantity to the micro-calorie meter, a peak value monitor measuring a peak value corresponding to an added heat quantity within an output signal from ...

article{d68a1cfe-bf19-48a0-af9e-709e06d7407b, abstract = {The single-aliquot regenerative-dose (SAR) protocols used in retrospective dosimetry for optically stimulated luminescence measurements have been mainly developed for archaeological and geological dating of quartz and feldspar. The aim in this study is to find a read-out protocol that can generate the most reproducible signal for household salt (NaCl) at absorbed doses below 100 mGy. The relation between the reproducibility of the signal, in terms of the ratio between given absorbed dose and SAR-calculated dose, and parameters such as test-dose pre-heat temperature has been studied. It was found that a temperature of 200°C yielded the best reproducibility in the SAR-calculated dose, which is a somewhat higher pre-heat temperature than what is used for dating of quartz.}, author = {Christiansson, Maria and Bernhardsson, Christian and Mattsson, Sören and Rääf, Christopher}, issn = {1742-3406}, language = {eng}, pages = {584--587}, ...

HUMAN RADIATION STUDIES: REMEMBERING THE EARLY YEARS Oral History of Health Physicist Karl Z. Morgan, Ph.D. Conducted January 7, 1995 By Marisa Caputo and Michael Yuffee United States Department of Energy Office of Human Radiation Experiments June 1995 FOREWORD n December 1993, U.S. Secretary of Energy Hazel R. OLeary announced her Openness Initiative. As part of this initiative, the Department of Energy undertook an effort to identify and catalog historical documents on radiation experiments that had used human subjects. The Office of Human Radiation Experiments coordinated the Departments search for records about these experiments. An enormous volume of historical records has been located. Many of these records were disorganized; often poorly cataloged, if at all; and scattered across the country in holding areas, archives, and records centers. The Department has produced a roadmap to the large universe of pertinent information: Human Radiation Experiments: The Department of Energy Roadmap ...

The harmonization process to set up and maintain an operational biological and physical retrospective dosimetry network : QA QM applied to the RENEB network. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.

HUMAN RADIATION STUDIES: REMEMBERING THE EARLY YEARS Oral History of Biochemist Waldo E. Cohn, Ph.D. Conducted January 18, 1995 By Michael Yuffee and Tom Fisher United States Department of Energy Office of Human Radiation Experiments June 1995 FOREWORD n December 1993, U.S. Secretary of Energy Hazel R. OLeary announced her Openness Initiative. As part of this initiative, the Department of Energy undertook an effort to identify and catalog historical documents on radiation experiments that had used human subjects. The Office of Human Radiation Experiments coordinated the Departments search for records about these experiments. An enormous volume of historical records has been located. Many of these records were disorganized; often poorly cataloged, if at all; and scattered across the country in holding areas, archives, and records centers. The Department has produced a roadmap to the large universe of pertinent information: Human Radiation Experiments: The Department of Energy Roadmap to the ...

MCNP{trademark} and LAHET{trademark} are two of the codes included in the LARAMIE (Los Alamos Radiation Modeling Interactive Environment) code system. Both MCNP and LAHET are three-dimensional continuous-energy Monte Carlo radiation transport codes. The capabilities of MCNP and LAHET are currently being merged into one code for the Accelerator Production of Tritium (APT) program at Los Alamos National Laboratory. Concurrently, a significant effort is underway to improve the accuracy of the physics in the merged code. In particular, full nuclear-data evaluations (in ENDF6 format) for many materials of importance to APT are being produced for incident neutrons and protons up to an energy of 150-MeV. After processing, cross-section tables based on these new evaluations will be available for use fin the merged code. In order to utilize these new cross-section tables, significant enhancements are required for the merged code. Neutron cross-section tables for MCNP currently specify emission data for neutrons

Purpose: To build a Monte Carlo dose verification tool for IMRT Plan by implementing a irradiation source model into DPM code. Extend the ability of DPM to calculate any incident angles and irregular-inhomogeneous fields. Methods: With the virtual source and the energy spectrum which unfolded from the accelerator measurement data,combined with optimized intensity maps to calculate the dose distribution of the irradiation irregular-inhomogeneous field. The irradiation source model of accelerator was substituted by a grid-based surface source. The contour and the intensity distribution of the surface source were optimized by ARTS (Accurate/Advanced Radiotherapy System) optimization module based on the tumor configuration. The weight of the emitter was decided by the grid intensity. The direction of the emitter was decided by the combination of the virtual source and the emitter emitting position. The photon energy spectrum unfolded from the accelerator measurement data was adjusted by compensating ...

The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument is one of four instruments on NASAs TIMED (Thermosphere Ionosphere Mesosphere Energetics Dynamics) satellite. The primary goal of the SABER experiment is to provide the data needed to advance our understanding of the fundamental processes governing the energetics, chemistry, dynamics, and transport in the mesosphere and lower thermosphere. SABER accomplishes this with global measurements of the atmosphere using a 10-channel broadband limb-scanning infrared radiometer covering the spectral range from 1.27 µm to 17 µm. These measurements are used to provide vertical profiles of kinetic temperature, pressure, geopotential height, volume mixing ratios for the trace species O3, CO2, H2O, [O], and [H], volume emission rates for 5.3 µm NO, 2.1 µm OH, 1.6 µm OH, and 1.27 µm O2(1Δ), cooling and heating rates for many CO2, O3, and O2 bands, and chemical heating rates for 7 important reactions ...

Dosimetry for targeted radionuclide therapy is necessary for treatment planning and radiation protection. Currently, there are no standard methods either for performing dosimetry or to evaluate the uncertainties inherent in the dosimetric calculations. In this paper, we present an experimental method using polymer gel dosimeters, whereby absorbed-dose distributions resulting from nonuniform distributions of activity may be determined directly from T(2) magnetic resonance imaging (MRI) as well as from scintigraphic images. A phantom containing a nonuniform distribution of I-131 was prepared by mixing 58 MBq of activity within the gel as it was solidifying. The resulting absorbed-dose distribution was determined directly from the MRI and from sequential single-photon emission computed tomography (SPECT) images using the Medical Internal Radiation Dose (MIRD) schema. The MRI data were quantified using 12 calibration vials uniformly irradiated by 0-12 MBq of I-131. The agreement between the two ...

Based on the SPIE bestseller The Art of Radiometry by James M. Palmer and Barbara G. Grant, this Field Guide provides a practical, hands-on approach to the subject that the engineer, scientist, or student can use in real time. Readers of the earlier work will recognize similar topics in condensed form, along with many new figures and a chapter on photometry.. Written from a systems engineering perspective, this book covers topics in optical radiation propagation, material properties, sources, detectors, system components, measurement, calibration, and photometry. Appendices provide material on SI units, conversion factors, source luminance data, and many other subjects. The books organization and extensive collection of diagrams, tables and graphs will enable the reader to efficiently identify and apply relevant information to radiometric problems arising amid the demands of todays fast-paced technical environment. I gratefully acknowledge the contributions to my education and career from ...

Buy or Rent Absolute Radiometry: Electrically Calibrated Thermal Detectors of Optical Radiation as an eTextbook and get instant access.

The purpose with this book is to enable the reader to find solutions to real-world problems. The focus is on the application of radiometry in various analysis and design scenarios. It is essential, however, to build on the foundation of solid theoretical understanding, and gain insight beyond graphs, tables and equations. Therefore, this book does not attempt to provide an extensive set of ready-to-use equations and data, but rather strives to provide insight into hidden subtleties in the field. The atmosphere provides opportunity for a particularly rich set of intriguing observations.. The strict dictionary definition of radiometry is the measurement of optical flux. In this book, the term radiometry is used in its wider context to specifically cover the calculation of flux as well. This wider definition is commonly used by practitioners in the field to cover all forms of manipulation, including creation, measurement, calculation, modeling, and simulation of optical flux. The focus of this ...

Purpose: Positron-emitting isotope distributions can be used for the image fusion of the carbon ion planning CT and online target verification PETCT, after radiation in the same decay period,the relationship between the same target volume and the SUV value of different every single fraction dose can be found,then the range of SUV for the radiation target could be decided.So this online range also can provide reference for the correlation and consistency in planning target dose verification and evaluation for the clinical trial. Methods: The Rando head phantom can be used as real body,the 10cc cube volume target contouring is done,beam ISO Center depth is 7.6cm and the 90 degree fixed carbon ion beams should be delivered in single fraction effective dose of 2.5GyE,5GyE and 8GyE.After irradiation,390 seconds later the 30 minutes PET-CT scanning is performed,parameters are set to 50Kg virtual weight,0.05mCi activity.MIM Maestro is used for the image processing and fusion,five 16mm diameter SUV ...

Health,HOUSTON Dec. 20 2004 Dont let the odd name fool you FLUKA is seri...A course on FLUKA one of the top radiation transport computer codes i...Called a Monte Carlo Radiation Transport Code because of how it uses r... Our environment is constantly being bombarded by radiation billions ...FLUKA works by simulating a particular environment in great detail. F...,International,gathering,at,UH,examines,top,computer,code,medicine,medical news today,latest medical news,medical newsletters,current medical news,latest medicine news

[18F]UCB-H was developed as a novel radiotracer with a high affinity for synaptic vesicle protein 2A, the binding site for the antiepileptic levetiracetam. The objectives of this study were to evaluate the radiation dosimetry of [18F]UCB-H in a preclinical trial and to determine the maximum injectable dose according to guidelines for human biomedical research. The radiation dosimetry was derived by organ harvesting and dynamic micro positron emission tomography (PET) imaging in mice, and the results of both methods were compared. Twenty-four male C57BL-6 mice were injected with 6.96 ± 0.81 MBq of [18F]UCB-H, and the biodistribution was determined by organ harvesting at 2, 5, 10, 30, 60, and 120 min (n = 4 for each time point). Dynamic microPET imaging was performed on five male C57BL-6 mice after the injection of 9.19 ± 3.40 MBq of [18F]UCB-H. A theoretical dynamic bladder model was applied to simulate urinary excretion. Human radiation dose estimates were derived from animal data using the

We propose to determine the response of a newly developed laser heated, vycor glass fiberoptic radiation dosimetry system to ionizing radiation in a clinical radiotherapy environment. Present systems measure only total dose or have limitations, such as instability, non-linearity, excessive size or a decoupled measurement system, making them unsuitable in a variety of clinical applications. This fiberoptic coupled dosimetry system is a new and innovative technology application which allows on-line measurement of instantaneous dose rate and total dose never before achievable. It offers a clear advantage in patient treatment delivery, allowing on-line corrections essential to a new generation of radiotherapy treatment machines with development of beam intensity modulation as an adjunct to 3D conformal therapy. It also has the advantage of submillimeter size and is minimally invasive, making it ideal for brachytherapy.. This system has the potential for stable, accurate, reproducible, clinically ...

PURPOSE The hematopoietically active (or red) bone marrow is the target tissue assigned in skeletal dosimetry models for assessment of stochastic effects (leukemia induction) as well as tissue reactions (marrow toxicity). Active marrow, however, is in reality a surrogate tissue region for specific cell populations, namely the hematopoietic stem and progenitor cells. Present models of active marrow dosimetry implicitly assume that these cells are uniformly localized throughout the marrow spaces of trabecular spongiosa. Data from Watchman et al. and Bourke et al., however, clearly indicate that there is a substantial spatial concentration gradient of these cells with the highest concentrations localized near the bone trabeculae surfaces. The purpose of the present study was thus to explore the dosimetric implications of these spatial gradients on active marrow dosimetry. METHODS Images of several bone sites from a 45-yr female were retagged to group active marrow voxels into 50 μm increments of marrow

Nitric Oxide Synthase Radiometric Assay Kit from Cayman Chemical,The NOS assay kit measures NOS activity by monitoring the conversion of radiolabeled arginine to citrulline. This assay is simple, sensitive, and specific for NOS activity and can be used with both crude and purified enzyme preparations. The kit includes sufficient materials and reagents for 50 tot,biological,biology supply,biology supplies,biology product

Electron paramagnetic resonance (EPR) dosimetry using the well established dosimeter material alanine is a generally accepted dosimetric method for measurements of high absorbed doses. Alanine EPR dosimetry is however not sensitive enough for high precision measurements of low (, 5 Gy) absorbed doses using reasonably measurement times and small dosimeters. It has therefore not been possible to fully exploit the benefits of EPR dosimetry for applications in radiation therapy.. The aim of this thesis was to show that sensitive EPR dosimetry is a competitive method for applications in radiation therapy fulfilling the requirements of measurement precision. Our strategy for reaching this goal was to search for new, more sensitive, EPR dosimeter materials fulfilling the criteria of being tissue equivalent, having a high radical yield and having a narrow EPR spectrum suitable for dosimetry. The best materials were found among formates and dithionates. Doping with small amounts of metal ions and ...

TY - JOUR. T1 - Impact of PET and MRI threshold-based tumor volume segmentation on patient-specific targeted radionuclide therapy dosimetry using CLR1404. AU - Besemer, Abigail E.. AU - Titz, Benjamin. AU - Grudzinski, Joseph J.. AU - Weichert, Jamey P.. AU - Kuo, John S.. AU - Robins, H. Ian. AU - Hall, Lance T.. AU - Bednarz, Bryan P.. PY - 2017/7/6. Y1 - 2017/7/6. N2 - Variations in tumor volume segmentation methods in targeted radionuclide therapy (TRT) may lead to dosimetric uncertainties. This work investigates the impact of PET and MRI threshold-based tumor segmentation on TRT dosimetry in patients with primary and metastatic brain tumors. In this study, PET/CT images of five brain cancer patients were acquired at 6, 24, and 48 h post-injection of 124I-CLR1404. The tumor volume was segmented using two standardized uptake value (SUV) threshold levels, two tumor-to-background ratio (TBR) threshold levels, and a T1 Gadolinium-enhanced MRI threshold. The dice similarity coefficient (DSC), ...

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Introduction: In radiotherapy treatment planning system (TPS), basic input is the data from computed tomography (CT) scan, which takes into account the effect of inhomogeneities in dose calculations. Measurement of CT numbers may be affected by scanner-specific parameters. Therefore, it is important to verify the effect of different CT scanning protocols on Hounsfield unit (HU) and its impact on dose calculation. This study was carried out to analyse the effect of different tube voltages on HU for various tissue substitutes in phantom and their dosimetric impact on dose calculation in TPS due to variation in HU-relative electron density (RED) calibration curves. Materials and Methods: HU for different density materials was obtained from CT images of the phantom acquired at various tube voltages. HU-RED calibration curves were drawn from CT images with various tissue substitutes acquired at different tube voltages used to quantify the error in dose calculation for different algorithms. Doses were

Definition of free-air ionization chamber in the Legal Dictionary - by Free online English dictionary and encyclopedia. What is free-air ionization chamber? Meaning of free-air ionization chamber as a legal term. What does free-air ionization chamber mean in law?

TY - JOUR. T1 - Dose estimation for repeated phosphorus-32 ingestion in human subjects. AU - Chao, J. H.. AU - Tseng, C. L.. AU - Hsieh, W. A.. AU - Hung, D. Z.. AU - Chang, W. P.. PY - 2001/1/15. Y1 - 2001/1/15. N2 - Dose estimation was conducted for internal phosphorus-32 exposure in one young male subject from repeated oral mis-ingestion for ,1 year. Since disclosure for previous continuous contamination, a series of urine samples were collected from this individual weekly for a period of ,2 months. P-32 radioactivity in urine samples were measured by the acid precipitation method. Estimation for retrospective total effective dose equivalent received by this subject was conducted for cumulative internal dose estimation. A minimum of 9.4 mSv was estimated for an assumed single ingestion. As this was a rare case in radiation protection and internal radiation dosimetry, its implications were of considerable significance. (C) 2000 Elsevier Science Ltd.. AB - Dose estimation was conducted for ...

The overall aim of the Concerted Action RBDATA-EULEP is to provide information to improve the assessments of intakes of radionuclides and of the resulting doses. This involves a review of the behaviour of radionuclides following intake, and the transfer of expertise on methodology by organising small training workshops. The main activity is the development of an electronic database, effectively an annotated bibliography, but the electronic format used facilitates extension, updating, and information retrieval. It consists of linked tables of references and experiments, with details and comments on the materials, procedures and results. By June 2002 it contained information on 524 inhalation, 282 ingestion and 164 injection experiments from 391 references. It will be extended, and Internet access provided. Prospective users include: groups developing standards for internal dosimetry, scientists conducting research on radionuclide biokinetics, and health physicists assessing the consequences of ...

Traceable calibration of a therapy-level dosemeter in terms of absorbed dose to water or air kerma. The service is available for thimble chambers or thin-window chambers, and offered in spring of each year.

July 2013 - First observations of atomic species in the MLT by SABER provide unique dataset for testing climate models and assessing basic understanding of the atmosphere on the edge of space. Earths mesospause region between 80 and 100 km altitude is unique because it is the lowest part of the atmosphere in which atoms are a permanent and significant part of the atmospheres composition. Specifically, atomic oxygen [O] and atomic hydrogen [H] are present in significant amounts, and in the case of [O], comprise up to 1% of the composition. These two species are critically important to the mesopause region because they govern the flow of energy from the Sun to the atmosphere. Ironically, both [O] and [H] are extremely difficult to observe from orbiting satellites because they do not readily emit energy that can be detected by conventional satellite instruments. The [O] and [H] abundances have been derived from measurements of ozone (O3) and hydroxyl (OH) which are directly and chemically related ...

Fig. 4. Detailed views of the deeper-water carbonates (Units A, B, C) and the calcareous marls to marlstones of the Marlstone member from the Kasımlar Formation of the Aşağiyaylabel (AS I, AS IV) and Karapinar (KA I-II & IV) sections. Well-bedded Kasimlarceltites beds at the base of the Kasımlar Formation (Carbonate member, Unit A) at the sections (a) AS I, (b) AS IV, (c) KA I and (d) KA II. Julian/Tuvalian boundary (Lower/Upper Carnian boundary) at the carbonate/marl transitional intervals at the sections (e) AS I and (f) KA IV within the Kasımlar Formations at the top of Unit C, below the Marlstone member. (g) Characteristic marls of the Marlstone member (AS I) within the Kasımlar Formation bearing the abundant Tuvalian ammonoid Paratropites cf. hoetzendorfii. (h) Layer with accumulation of the bivalve Halobia and pyrite cubes within the Marlstone member from AS I. (i) Sandstone layer of the Marlstone member, AS I. (j) Breccia layer with shallow-water components within the Marlstone ...

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Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 3.0 Unported ...

TY - JOUR. T1 - Improving TBI lung dose calculations. T2 - Can the treatment planning system help?. AU - Lamichhane, Narottam. AU - Studenski, Matthew T.. PY - 2020/6/1. Y1 - 2020/6/1. N2 - Lung toxicity is a serious concern during total body irradiation (TBI). Therefore, evaluation of accurate dose calculation when using lung blocks is of utmost importance. Existing clinical treatment planning systems can perform the calculation but there are large inaccuracies when calculating volumetric dose at extended distances in the presence of high atomic number materials. Percent depth dose and absolute dose measurements acquired at 400 cm SSD with a cerrobend block were compared with calculated values from the Eclipse treatment planning system using AAA and Acuros. The block was simulated in 2 ways; (1) manually drawing a contour to mimic the block and (2) creating a virtual block in the accessory tray. Although the relative dose distribution was accurately calculated, larger deviations of around 50% ...

Purpose: Size, shape, and the position of paired organs are different in abdomen. However, the counterpart organs are conventionally treated jointly together in internal dosimetry. This study was performed to quantify the difference of specific absor

For over 65 years, PerkinElmer has been a leading provider and partner for radiometric detection solutions ranging from instruments and radiochemicals, to liquid scintillation cocktails, vials, and microplates.

Today, dosimeters are used generally for dosimetry of the diagnostic X-ray beam. Ionization chambers are appropriate instruments for monitoring and also the dosimetry of X-ray beam in medical diagnostic equipment. The present work introduces design and investigation of a new ring-shaped monitor chamber with a PMMA body, graphite-coated PMMA windows (0.5 mm thick), a special graphite-foil central electrode (0.1 mm thick, 0.7 g/cm3 dense) that creating two sensitive volumes and a central hole for crossing the radiation beam with less attenuation. The results of performance tests conducted at the Nuclear Science and Technology Research Institute, AEOI in Karaj- Iran proved the high short and long-term stability, the very low leakage current, the low directional dependence and very high ion collection efficiency through the special design of the collecting electrode. Moreover, the FLUKA Monte Carlo simulations certified the negligible effect of central electrode on this new ring-shaped monitor chamber.

195mPt-cisplatin is regarded as a promising imaging agent for optimizing dosage in patients receiving cisplatin chemotherapy. We investigated the whole-body distribution and radiation dosimetry of 195mPt-cisplatin in humans. Methods: Whole-body scans were obtained up to 144 h after intravenous injection of 112.4 MBq 195mPt-cisplatin in each of five subjects. Blood samples were taken at various times up to 144 h after injection. Urine was collected up to 114 h after injection for calculation of renal clearance and wholebody clearance. Time/activity curves were generated by fitting the organ-specific geometric mean counts, obtained from regions of interest, on the respective images as a function of the time after injection. OLINDA software package was applied to calculate the absorbed radiation dose for various organs. Results: Most of the activity (32 ± 4%) was excreted in the urine during the first 5 h. The effective clearance half-life derived from extrapolation of the whole-body curve was 40 ...

A simple and convenient assay for indoleamine 2,3-dioxygenase has been developed. This depends on the conversion of D-[ring-2-14C]tryptophan to [14C]formate, excess substrate is removed by adsorption onto charcoal. This assay, which is 20-fold more sensitive than previous procedures, is applicable both to crude extracts and to large numbers of samples. Activity in rat tissues is very much lower than in those of the rabbit; measureable activity is found only in the stomach, spleen, intestine and kidney. Enzyme activity in the rat intestine was increased by 50% in rats pretreated with L-tryptophan. ...

Grid size defines the number of grid tiles in x and y for statistics to run on. For example, a grid size of 10 will result in 100 grid tiles (10 in x, 10 in y). Depending on the scene, this can have a big affect. For example, frames with relatively contiguous radiometry can use small grid sizes. Complex scenes, such as a frame containing water, urban, and rural/vegatated areas, usually require a higher grid size/density to prevent one radiometrically contiguous area from affecting another area. For example, consider a patch of dark green vegetation surrounded by say, lighter colored grain crops. If the grid size is significantly larger than the dark green patch, the output (depending on the constraints applied) will wash out the dark green because of the statistical influence of the DN values of the lighter colored grains. However, sometimes the problem outlined in this example can be impossible to avoid! This is why dodging is both an science and an art ...

Cytogenetic dicentric kromosom (DC) analysen kvantifiserer eksponering for ioniserende stråling. Automatisert Dicentric kromosom ID og...

20. Introduction to Cone Beam Computed Tomography. Ernest W. N. Lam. This technology, first described in 1998 for applications in dentistry (Mozzo et al., 1998), employs a cone-shaped X-ray beam emanating from a point source coupled with a planar digital sensor. During image acquisition, both the radiation source and sensor rotate around the patient, who is stationary. There are two classes of cone beam systems currently, ones that employ small fields of view with dimensions of less than 8 cm, and large fields of view with dimensions of greater than 8 cm upward to 30 cm.. Unlike intraoral digital imaging, the anatomy of the area imaged is recreated in three dimensions rather than two. The three-dimensional (3D) elements that recreate the anatomy are referred to as cube-shaped volume elements or voxels. Small field of view systems (Figure 20.1) employ pixel dimensions as low as 0.076 mm while the larger field machines employ pixel dimensions of between 0.20 mm and 0.40 mm.. ...

Electron paramagnetic resonance (EPR) dosimetry using the well established dosimeter material alanine is a generally accepted dosimetric method for measurements of high absorbed doses. Alanine EPR dosimetry is however not sensitive enough for high precision measurements of low (, 5 Gy) absorbed doses using reasonably measurement times and small dosimeters. It has therefore not been possible to fully exploit the benefits of EPR dosimetry for applications in radiation therapy.. The aim of this thesis was to show that sensitive EPR dosimetry is a competitive method for applications in radiation therapy fulfilling the requirements of measurement precision. Our strategy for reaching this goal was to search for new, more sensitive, EPR dosimeter materials fulfilling the criteria of being tissue equivalent, having a high radical yield and having a narrow EPR spectrum suitable for dosimetry. The best materials were found among formates and dithionates. Doping with small amounts of metal ions and ...

Malinen, Eirik; Vestad, Tor Arne; Hult, Elin Agathe; Hole, Eli Olaug & Sagstuen, Einar (2004). Estimation of X-ray beam quality by electron paramagnetic resonance (EPR) spectroscopy. Applied Radiation and Isotopes. ISSN 0969-8043. 60, s 929- 937 Vis sammendrag A novel dosimetry system using EPR spectroscopy to determine X-ray beam quality is proposed. The composite dosimetry system is a mixture of two polycrystalline substances, where the two materials have different X-ray absorption properties. The composite dosimeters, consisting of polycrystalline lithium formate monohydrate and calcium formate, were prepared as pellets, X-irradiated and analyzed with EPR spectroscopy. Taking the ratio between the EPR intensities of the two substances constituting the dosimeter, a measure of the beam quality was obtained in terms of the equivalent photon energy. The intensity ratio was calculated by a simple EPR spectrum reconstruction method. Plotting the logarithm of the EPR intensity ratio against the ...

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2010 AAPM Annual Meeting Allen Li For more information about the American Association of Physicists in Medicine, visit http://www.aapm.org/ The goal of…

v. VEGETATION-2. The time series of extractions covers the years: 2006 to 2009. These data were distributed in a predefined format and constitute what is hereafter called the reference dataset. Each participating team applied its vicarious calibration methodologies and/or sensor-to-sensor radiometric intercomparison methodologies to this reference dataset. MERIS data (2nd reprocessing) were chosen as a radiometric reference to which other sensor radiometry was compared. The comparison was carried out for each methodology and for each site using standardised statistical indicators associated to the time series of radiometric differences between MERIS and other sensors. Reference Dataset is available: You are welcome to download the reference dataset, sensor spectral responses and a ReadMe from: [DOWNLOAD DATASET HERE]. The reference dataset is fully described in the WG4 Final Report. It was generated from three separate data sources; DIMITRI (maintained by ESA and ARGANS), SADE (CNES) and RAL. It ...

A Greens function based methodology has been developed and implemented with the view to optimize the focusing properties and thus the performance of a Microwave Radiometry Imaging System (MiRaIS). The system consists of an ellipsoidal conductive wall cavity and a sensitive radiometric receiver and its operation principal is based on the convergence of the radiation from one focal point, where the subject or phantom is placed, on the other, where the receiver antenna is positioned. A two-layered cylinder is used to model the human head with the semi-analytical Greens function technique. The imaging configuration is enhanced by different matching structures of various materials which are placed on the surface of both the human head model and the antenna inside the ellipsoidal. Numerical code executions have been realized and the results for the electric field distribution inside the head are presented for materials of various dielectric properties and for left handed materials at two different ...

PhD Project - Magnetic Resonance Imaging (MRI) and Microwave Radiometry (MR) Based Measurement of the Efficacy of Hot and Cold Treatments at University of Edinburgh, listed on FindAPhD.com

Two well-known examples of global environmental problems are the ozone depletion and the enhanced greenhouse effect. The importance and the complexity of these questions generate a demand for improved atmospheric observations, and microwave radiometry is an approach which is increasingly important for measurements of the middle atmosphere (10-100 km). This technique is suitable for the detection of e.g. O|sub>3|/sub>, H|sub>2|/sub>O, ClO, HCl, N|sub>2|/sub>O and HNO|sub>3|/sub>, all of which are species with key roles for ozone chemistry and/or the greenhouse effect. An important step in the development of microwave radiometry will be taken by the Odin satellite, as it will carry the first sub-mm instrument for atmospheric observations from space.|p /> Microwave radiometry needs an inversion process to convert measured emission spectra to vertical distributions of the gases studied. The inversion forms an ill-posed problem, and requires that atmospheric radiative transfer and sensor characteristics can

Read MEASUREMENT OF INTERNAL RADIATION DOSE DISTRIBUTION IN CT EXAMINATIONS USING POLYETHYLENE TEREPHTHALATE RESIN, Radiation Protection Dosimetry on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.

Computational anthropomorphic phantoms are computer models of human anatomy used in the calculation of radiation dose distribution in the human body upon exposure to a radiation source. Depending on the manner to represent human anatomy, they are categorized into two classes: stylized and tomographic phantoms. Stylized phantoms, which have mainly been developed at the Oak Ridge National Laboratory (ORNL), describe human anatomy by using simple mathematical equations of analytical geometry. Several improved stylized phantoms such as male and female adults, pediatric series, and enhanced organ models have been developed following the first hermaphrodite adult stylized phantom, Medical Internal Radiation Dose (MIRD)-5 phantom. Although stylized phantoms have significantly contributed to dosimetry calculation, they provide only approximations of the true anatomical features of the human body and the resulting organ dose distribution. An alternative class of computational phantom, the tomographic ...

The internal dosimetry program conducts analyses and consultation for the study and management of internal radiation exposure. The analyses include collection of information on work and residence history, past and current radiation exposure, bioassays to measure the presence of radionuclides within body tissues (in vivo) or body fluids and excretions (in vitro), and calculation of dose associated with observed uptakes. Consultation includes interpretation of bioassay results and can extend to collaboration with health care professionals and workplace supervisors. The internal dosimetry program includes a documented quality assurance program for in vivo bioassays and a comprehensive technical basis for the assessment of internal exposure. The program meets the requirements and recommendations of the DOE Implementation Guide for Internal Dosimetry Programs (10 CFR 835) and the American National Standards Institute Performance Criteria for Radiobioassay (N13.30). The Center is also involved in the ...

TY - JOUR. T1 - Three-dimensional polymer gel dosimetry using an onboard 0.35 T magnetic resonance imaging scanner. T2 - A simulation study. AU - Zhang, Lei. AU - Hu, Yanle. AU - Du, Dongsu. AU - Green, Olga L.. AU - Wooten, H. Omar. AU - Li, H. Harold. PY - 2015/7/1. Y1 - 2015/7/1. UR - http://www.scopus.com/inward/record.url?scp=84941623891&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=84941623891&partnerID=8YFLogxK. U2 - 10.4103/0971-6203.165081. DO - 10.4103/0971-6203.165081. M3 - Letter. AN - SCOPUS:84941623891. VL - 40. SP - 176. EP - 180. JO - Journal of Medical Physics. JF - Journal of Medical Physics. SN - 0971-6203. IS - 3. ER - ...

In connection with clinical 131I-MIBG studies of patients with suspected pheochromocytoma and adrenomedullary hyperplasia quantitative biokinetic data have been collected in order to improve the present estimations of absorbed dose to various organs and tissues. Whole-body profiles as a function of time were measured with a whole-body counter. The retention in the total body and in the thyroid gland could be derived from the measured whole-body profiles by summing up the corresponding values. The retention of 131I-MIBG could not be exactly measured for further organs from the whole-body profiles in man. For this reason animal studies were performed with mice. The biokinetic animal data were transferred to man in form of the cumulative activity for the various organs. The mean absorbed dose for selected organs per injected activity unit was calculated using the concept of absorbed fractions (MIRD method) taking into account the radioactivity within the remaining body. Except for both the adrenal medulla

Clinical studies of hypothermal neural rescue therapy for newborn infants who have suffered hypoxia-ischaemia are currently hindered by the difficulty in measuring deep brain temperature. This paper addresses: the specific requirements for this measurement problem, the design of a proposed radiometer system, a method for retrieving the temperature profile within the cooled head, and an estimation of the precision of the measurement of deep brain temperature using the technique. A five-frequency-band radiometer with a contact-type antenna operating within the range 1-4 GHz is proposed to obtain brightness temperatures corresponding to temperature profiles predicted by a realistic thermal model of the cooled baby head. The problems of retrieving the temperature profile from this set of brightness temperatures, and the estimation of its precision, are solved using a combination of model fitting and Monte Carlo techniques. The results of this paper show that the proposed technique is feasible, that ...

BioAssay record AID 1070521 submitted by ChEMBL: Antimicrobial activity against Mycobacterium tuberculosis H37Rv by BACTEC radiometric assay.

The Helical Tomotherapy treatment planning system uses a relatively accurate collapsed cone convolution/superposition algorithm for dose calculation and, as with other non -Monte Carlo algorithms, charged particle equilibrium is assumed in the dose calculation. For this reason we can expect inaccuracy in predicting dose distribution in the presence of significant inhomogeneities in patient geometry where this assumption is not satisfied. The dose distribution accuracy of the HT TPS was then tested in case of low density lung lesions.. Before the validation of the dose calculation algorithm in inhomogeneous media, the agreement between measured and calculated dose distributions for lung treatments was verified in a homogeneous phantom. Excellent agreement was found for point dose measurements with most of the data within ± 2%; an average percentage discrepancy equal to 0.85% (1SD = 0.5%) was estimated by considering all the points, both in PTV and in OAR regions. Good agreement (3%- 3 mm ...

TY - JOUR. T1 - Investigation of 90Y-avidin for prostate cancer brachytherapy. T2 - A dosimetric model for a phase I-II clinical study. AU - Botta, Francesca. AU - Cremonesi, Marta. AU - Ferrari, Mahila E.. AU - Amato, Ernesto. AU - Guerriero, Francesco. AU - Vavassori, Andrea. AU - Sarnelli, Anna. AU - Severi, Stefano. AU - Pedroli, Guido. AU - Paganelli, Giovanni. PY - 2013/7. Y1 - 2013/7. N2 - Purpose: A novel method for prostate irradiation is investigated. Similarly to 125I or 103Pd seed brachytherapy, 90Y- avidin could be injected via the perineum under ultrasound image guidance. This study inspects the theoretical feasibility with a dosimetric model based on Monte Carlo simulation. Methods: A geometrical model of the prostate, urethra and rectum was designed. The linear-quadratic model was applied to convert 125I absorbed dose prescription/constraints into 90Y dose through biological effective dose (BED) calculation. The optimal 90Y-avidin injection strategy for the present model was ...

The performance of microwave radiometers can be seriously degraded by the presence of radio-frequency interference (RFI). Spurious signals and harmonics from lower frequency bands, spread-spectrum signals overlapping the protected band of operation, or out-of-band emissions not properly rejected by the pre-detection filters due to the finite rejection modify the detected power and the estimated antenna temperature from which the geophysical parameters will be retrieved. In recent years, techniques to detect the presence of RFI have been developed. They include time- and/or frequency domain analyses, or statistical analysis of the received signal which, in the absence of RFI, must be a zero-mean Gaussian process. Current mitigation techniques are mostly based on blanking in the time and/or frequency domains where RFI has been detected. However, in some geographical areas, RFI is so persistent in time that is not possible to acquire RFI-free radiometric data. In other applications such as sea ...

Two different testicular tissues have to be distinguished in regard to radiation damage: first the seminiferous tubules, corresponding to the sites of spermatogenesis, which are extremely radiosensitive. Second the testosterone secreting Leydig cells, which are considered to be less radiosensitive. This study aims to estimate testicular dose and the associated risks for infertility and hereditary effects from Abdominal and pelvic irradiation. Radiotherapy was simulated on a humanoid phantom using a 15 MV photon beam. Testicular dose was measured for various field sizes and tissue thicknesses along beam axis using an ionization chamber and TLD. For transmission Factor Also common method of measuring the absorbed dose distribution and electron contamination in the build-up region of high-energy beams for radiation therapy is by means of parallel-plate Ionisation chambers. Gonadal dose was reduced by placing lead cups around the testes supplemented by a field edge block. For a tumor dose of 100 cGy,

APPENDIX 1 RESULTS OF DOD HUMAN RADIATION EXPERIMENT RECORDS SEARCH On 15 January 1994, Executive Order (EO) identified human radiation experiments (HRE) in the following manner: (1) Experiments

A prototype of a new dose-verification system has been developed to facilitate prevention and identification of dose delivery errors in remotely afterloaded brachytherapy. The system allows for automatic online in vivo dosimetry directly in the tumor region using small passive detector probes that f …

TY - BOOK AU - Mitrović, Marko PY - 2018 UR - http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=50768655 UR - http://nardus.mpn.gov.rs/123456789/10352 UR - http://vet-erinar.vet.bg.ac.rs/handle/123456789/46 AB - Usage of computed tomography (CT) is very frequent, both in human and veterinary medicine. Bearing in mind that the radiation dose, that patient receive during CT examination, is several times higher than during conventional radiography, much attention is devoted to evaluate necessity of this diagnostic procedure and its optimization, along with the minimal exposure of patients to the radiation load. According to this, the main goal of these investigations was to explore a correlation between absorbed radiation doses and the degree of activity of antioxidant enzymes in rabbit organs following CT examination performed by different tube voltage and amperage values. Experiment was conducted on 66 mature male New Zealand rabbits divided in 11 groups, consisting of six animals ...

British Committee on Radiation Units and Measurements, (1997) Advice on the implications of the conversion coefficients for external radiations published in ICRP publication 74 and by ICRU publication 57. J. Radiol. Prot., 17. pp. 201-204. Full text not available from this repository ...

AFTER a radiation accident in July 1969 we had the opportunity of comparing radiation dose estimates made by biological and physical methods. The biological method involved counting chromosome aberrations in cultured peripheral blood lymphocytes, and the physical method was based on a reconstruction of the accident. For the conditions of this accident a reasonable agreement was obtained between the two methods, which adds to the growing confidence in the use of chromosome aberration counting for dose assessment in radiation accidents.

Abstract: Purpose: Radiation therapy treatment planning is a trial-and-error, often time-consuming process. An optimal dose distribution based on a specific anatomy can be predicted by pre-trained deep learning (DL) models. However, dose distributions are often optimized based on not only patient-specific anatomy but also physician preferred trade-offs between planning target volume (PTV) coverage and organ at risk (OAR) sparing. Therefore, it is desirable to allow physicians to fine-tune the dose distribution predicted based on patient anatomy. In this work, we developed a DL model to predict the individualized 3D dose distributions by using not only the anatomy but also the desired PTV/OAR trade-offs, as represented by a dose volume histogram (DVH), as inputs. Methods: The desired DVH, fine-tuned by physicians from the initially predicted DVH, is first projected onto the Pareto surface, then converted into a vector, and then concatenated with mask feature maps. The network output for training ...

Man-made Radio Frequency Interference (RFI) is an increasingly threatening problem for passive microwave radiometry from space. The problem is presently very evident in L-band data from SMOS, but it is realized that it is already now a problem at other traditional radiometer bands at C, X, and Ku bands. Studies of data from existing radiometer systems have revealed this, and clearly indicates increasing RFI intensity over time. Thus, future missions have to take this into consideration, and dedicated hardware and algorithms to safely detect and mitigate RFI must be included. The design of such an RFI processor is discussed, and resource demands on the spacecraft are indicated ...

An integral equation relating the lateral absorbed dose profile of a photon beam to the resultant absorbed dose distribution during single-turn rotating-beam therapy has been set up and solved for the case of a cylindrical phantom with the axis of rotation coinciding with the axis of symmetry of the cylinder. In the first approximation the results obtained are also valid when the axis of rotation is somewhat off-centred, even in a phantom that deviates from circular symmetry, provided the rotation is performed in both clockwise and counter clockwise directions. The calculated dose profiles indicate that improved dose uniformity can be achieved using a new type of non-linear wedge-shaped filter, which can easily be designed using the derived general analytic solution to the integral equation.. ...

If you have a question about this talk, please contact David Titterington.. ALMA is now being commissioned at its 5000m-high, extremely dry, site. Currently there are nine antennas at the high site routinely making tests and observing science verifications targets. In this talk we will describe the initial results of water vapour radiometric phase correction which is a crucial component in the ALMA calibration plan. We will discuss the hardware, the algorithms developed here in Cambridge and, using the first year of test data from the site, the effectiveness of the overall system. We will also show results of measurement of the properties of atmospheric turbulence based on the water vapour radiometer data.. This talk is part of the Cavendish Astrophysics Seminars series.. ...

Ralph A. Sawyer was a University of Michigan physicist, distinguished for his research in spectroscopy, radiometry, and various forms of spectrographic analysis, and later in atomic energy research. While at the University of Michigan, and in different administrative positions, Sawyer was responsible for the growth of the Universitys research program in the 1950s and 1960s.. Sawyer was born in 1895 in Atkinson, New Hampshire. After graduating from Dartmouth in 1915, Sawyer enrolled at the University of Chicago, becoming an assistant in physics in 1917. In 1918 he entered the Navy and designed optical instruments for the Bureau of Ordnance. After leaving the Navy in 1919, he received is Ph.D. degree from Chicago and joined the physics department of the University of Michigan. Sawyer rose to the rank of full professor by 1930. During his career he became a specialist in the fields of spectroscopy, radiometry, extreme ultraviolet spectra, series analysis of line spectra, hyperfind structure of ...

This popular guidebook answers questions such as: What is radiometry and why would I need it? What about emissivity, reflectivity and atmospheric effects? How does resolution impact radiometry?

4-[18F] fluorobenzyl dexetimide (F-DEX) is the first non-subtype selective fluorine-18 labelled tracer for muscarinic receptors (mAChR) used in humans. A recent first-in-human study found high regional brain uptake with low variation in normal subjects. Disturbance of mAChR has been reported in Alzheimers and Parkinsons disease, schizophrenia and depression and various cardiac diseases. The following work assesses the biodistribution, organ tracer kinetics and radiation dose associated with F-DEX. Dose calculations were based on activity uptake derived from multiple time point whole body PET CT imaging and the organ-specific dosimetric S-factors derived from the ICRP 133 standard man and woman mathematical phantoms. Effective doses were calculated using the latest ICRP tissue weighting factors. Serial images and time activity curves demonstrate high brain and left ventricular myocardial uptake (5% and 0.65% of injected activity, respectively) with greater retention in brain than myocardium. The mean

CHIAVASSA S, AUBINEAU-LANIECE I, BITAR A, FERRER L, LISBONA A, BARBET J, FRANCK D, JOURDAIN JR, BARDIES M (2006). Validation of a personalised dosimetric evaluation tool (OEDIPE) for targeted radiotherapy based on the Monte Carlo MCNPX code. Phys. Med. Biol, 51 :601-616.. CHIAVASSA S, BARDIES M, GUIRAUD-VITAUX F, BRUEL D, JOURDAIN JR, FRANCK D, AUBINEAU-LANIECE I (2005). OEDIPE: A personalised dosimetric tool associating voxel-based models with MCNPX. Cancer Biotherapy and Radiopharmaceutical, 20(3):325-332. PIERRAT N, DE CARLAN L, CAVADORE D, FRANCK D (2005). Application of Monte Carlo calculation for the virtual calibration of a low-energy in vivo counting system. IEEE TNS, 52(5):1353-1358.. **BORISSOV N, FRANCK D, DE CARLAN L, LAVAL L (2002). A new graphical user interface for fast construction of computation phantoms and MCNP calculations: Application to calibration of in vivo measurement system. Health Phys, 83(2):272-279. ...

phdthesis{ddfe7edf-3e52-4cfc-9c2b-5ec21021bbea, abstract = {Cancer is one of the main causes of death in the world, particularly in developing countries and is considered as a major public health problem. Radiation therapy has been an important modality for treatment of cancer for many decades. It can be used as a sole treatment modality or in combination with for example surgery, chemotherapy, hormone therapy and/or immune therapy. It has been calculated that 52% of all cancer patients, at least once during their illness, would benefit from external beam radiation therapy. The purpose of radiation therapy is to deliver an accurate and homogenous absorbed dose of radiation to the tumour sufficient to either cure the patient or to shrink the tumour for pain relief. To reduce the probability of complications the absorbed dose to surrounding normal tissue should be minimized. For a successful outcome of the treatment it is therefore crucial to deliver geometrically and dosimetrically precise ...

The issue of radiation dosage is confusing to many clinicians. Part of this confusion is related to the terminology, especially given that radiation-related quantities and effects can be expressed in many different ways and competing terms have been used inconsistently in the past. Radiation dose or absorbed radiation dose refers to the amount of energy deposited by ionizing radiation per unit mass in a patients body as a result of exposure. The units of absorbed dose are rads or millirads in conventional units or gray in SI units. A pertinent concept is that of the effective dose, expressed in units of rem or millirem or the SI unit of sievert or millisievert. Effective dose takes into account the different risks of absorbed dose to various organs and is a useful method of comparing risk among different diagnostic tests. The effective dose equivalent is the sum of the products of the effective dose to the organ or tissue and weighting factors specific to each of the body organs or tissues. The ...

Using an amorphous silicon (a-Si) EPID for transit dosimetry requires detailed characterization of its dosimetric response in a variety of conditions. In this study, a measurement-based model was developed to calibrate an a-Si EPID response to dose for transit dosimetry by comparison with a reference ionization chamber. The ionization chamber reference depth and the required additional buildup thickness for electronic portal imaging devices (EPID) transit dosimetry were determined. The combined effects of changes in radiation field size, phantom thickness, and the off-axis distance on EPID transit dosimetry were characterized. The effect of scattered radiation on out-of-field response was investigated for different field sizes and phantom thicknesses by evaluation of the differences in image profiles and in-water measured profiles. An algorithm was developed to automatically apply these corrections to EPID images based on the user-specified field size and phantom thickness. The average phantom ...

Introduction. Absorbed dose is the most important physical quantity for evaluating potential biological response as a result of exposure to ionizing radiation (IR). Physical dosimetry is commonly performed by instruments that are sensitive to the physical effects of IR. However, in most cases involving real or suspected accidental exposure, people are not wearing a dosimeter and, as a result, physical dosimetry is not straightforward. For such situations, the study of early biological effects induced by an exposure to IR has been proposed as either a complementary or an alternative method for dose assessment (Downing, 2000; Amaral, 2002; Bonassi and Au, 2002; Ramalho and Nascimento, 1991; Ramalho et al., 1995; Voisin et al., 2001).. Biological dosimetry (biodosimetry) is based on the investigation of radioinduced biological effects (bioindicators) in order to correlate them with the radiation dose. Among the bioindicators employed in biodosimetry, the scoring of chromosome aberrations (CA) is ...

FFF beams have lower mean energy (tissue-phantom ratio at the depths of 20 and 10 cm (TPR 20/10): X6, 0.667; X6FFF, 0.631; X10, 0.738; X10FFF, 0.692); maximum dose is located closer to the surface; and surface dose increases by 10%. FFF profiles have sharper but faster diverging penumbra. For small fields and shallow depths, dose outside a field is lower for FFF beams; however, the advantage fades with increasing phantom scatter. Output increases 2.26 times for X6FFF and 4.03 times for X10FFF and is less variable with field size; collimator exchange effect is reduced. A good agreement between modeled and measured data is observed. Criteria of 2% depth-dose and 2-mm distance-to-agreement are always met ...

For 99mTc sestamibi rest-stress imaging, good agreement exists between E1 from ICRP (11.3 mSv) and PI (14.6 mSv for 4.8-hour urinary void, 13.5 mSv for 2-hour void) dose coefficients. The higher E1 with the longer void time is primarily due to the higher equivalent dose to the bladder wall (41 versus 21 mSv) and demonstrates the potential dose-reduction benefit of hydration and early micturition after radiopharmaceutical administration. Much of the difference between ICRP- and PI-derived E1 is due to an idiosyncrasy in the methodology of ICRP Publication 60 for determining dose to remainder organs, which was later amended.22 For 99mTc tetrofosmin, even closer agreement exists between ICRP- and PI-derived E1 values, which are 9.3 and 9.7 mSv, respectively.. 201Tl dosimetry varies markedly between manufacturers PIs. E1 for a 3.5-mCi injection determined with dose coefficients from ICRP Publication 53 Addendum 5 and PIs 1, 2, and 3 are 22.0, 28.7, 9.3, and 28.4 mSv, respectively. When we examine ...

A general purpose high accuracy dosimeter reader, 80, for determination of a treatment condition, based on comparison of an image of treated dosimeter, 111, with a series of images of pre-treated dosimeter, 114, is disclosed. A dosimeter undergoes noticeable changes, such as a color change upon treatment with certain materials, such as toxic gases and processes, such as ionizing radiation and sterilization is pre-treated. The dosimeter is imaged with an imaging device, 115, such as charge-coupled device camera and images of the dosimeter or the changes, e.g., color change, are stored in an information storage device, 118. In order to determine the treatment condition, the treatment dosimeter is imaged and the image is compared with the series of pre-treated images of the dosimeter using software. The closest match of the treated dosimeter with the pre-treated and pre-imaged dosimeter would indicate the treatment conditions. The process and device can be used for almost any indicating device, process and

More and more advanced radiotherapy techniques have been adopted for post-mastectomy radiotherapies (PMRT). Patient dose reconstruction is challenging for these advanced techniques because they increase the low out-of-field dose area while the accuracy of out-of-field dose calculations by current commercial treatment planning systems (TPSs) is poor. We aim to measure and model the out-of-field radiation doses from various advanced PMRT techniques. PMRT treatment plans for an anthropomorphic phantom were generated, including volumetric modulated arc therapy (VMAT) with standard and flattening-filter-free (FFF) photon beams, mixed beam therapy, 4-field intensity modulated radiation therapy (IMRT), and Tomotherapy ...

In radiation therapy it is very important to accurately measure the amount of radiation delivered. The effectiveness of the treatment depends on delivering the dose with an accuracy of 5% or better. The dosimetry in different clinics must also be consistent. For these reasons national and international calibration protocols have been developed. In the US, the American Association of Physicists in Medicine (AAPM) has published several national dosimetry protocols for the calibration of high-energy photon and electron beams. In this study the absorbed dose-to-water determined according to TG-21 and TG-51 protocols, developed by Task Group 21 and Task Group 51 of the Radiation Therapy of AAPM, are compared. The older protocol, TG-21, is based on exposure calibrated ionization chambers using a ⁶⁰Co beam. Many standards laboratories have started to replace exposure standards with those involving absorbed dose-to-water. The new protocol, TG-51, is based on absorbed dose-to-water calibrated ...

Purpose : To review major radiation accidents that have occurred over a 50 year period. To identify common factors, since feedback may prevent recurrence. Methods : Accidents are classified according to the difficulties involved in their management and to the delay between their occurrence and their recognition. Results : The rate of severe...

Conversion chart for rad (Absorbed radiation dose, radiation units conversion). Instant units and measurements conversion, metric conversion and other systems. Many units supported from common to very exotic ones.

TY - JOUR. T1 - Murine S factors for liver, spleen, and kidney. AU - Kolbert, Katherine S.. AU - Watson, Timotheus. AU - Matei, Cornelia. AU - Xu, Su. AU - Koutcher, Jason A.. AU - Sgouros, George. N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.. PY - 2003/5. Y1 - 2003/5. N2 - Preclinical evaluation of new radiopharmaceuticals is performed in animal systems before testing is started in humans. These studies, often performed in murine or other rodent models, are important in understanding the relationship between absorbed dose and response, which can be translated to preclinical results for humans. In performing such calculations, either electrons are assumed to deposit all of their energy locally or idealized models of mouse anatomy are used to determine absorbed fractions. Photon contributions are generally considered negligible. To improve the accuracy of such absorbed dose calculations, mouse-specific S factors for 131I, 153Sm, 32P, 188Re, and 90Y have been generated, and ...

Title: PRWeb- Medical Internal Medicine, Description: Latest news releases for Health- Internal Medicine from PRWeb, By: Feedage Forager, ID: 241530, Grade: 87, Type: RSS20

Sarcasm by the teaspoon, tablespoon, and shotglass. Social Engineering through words, tainted truth, sarcasm, chaos and cacophony. A pandemonium of pandering, pondering and parading of thoughts and ideas. A soapbox pulpit. Pull up a chair and stare at the orange glare. literary review, books, Rants, cooking, stupid dead people, child raising, bad product rants-- Stay tuned for more. ...

Absorbed dose to active bone marrow is a predictor of hematological toxicity in molecular radiotherapy. Due to the complex composition of bone marrow tissue, the necessity to improve the personalized dosimetry has led to the application of non-conventional imaging methods in nuclear medicine. The aim of this study is to apply magnetic resonance imaging (MRI) for quantification of the fat fraction in lumbar vertebrae and to analyze its implications for bone marrow dosimetry. Methods First, a highly accelerated two-point Dixon MRI sequence for fat-water separation was validated in a 3T system against the magnetic resonance spectroscopy (MRS) gold standard ...

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IMRT Homogeneous Phantom - Complete QA from CT imaging to dose verification. CIRS is the leading manufacturer of medical imaging phantoms and simulators for radiation therapy QA, dosimetry, diagnostic imaging QA as well as training and demonstration phantom

Science & Technology, Life Sciences & Biomedicine, Radiology, Nuclear Medicine & Medical Imaging, RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING, electronic portal imaging (EPI), radiation therapy, dose verification, PORTAL DOSE IMAGES, VERIFICATION, ENERGY, SETUP ...

Radiation Research publishes work dealing with radiation effects and related subjects in the areas of physics, chemistry, biology and medicine.

TY - JOUR. T1 - Uptake, depuration, and radiation dose estimation in zebrafish exposed to radionuclides via aqueous or dietary routes. AU - Reinardy, Helena C.. AU - Teyssie, Jean-Louis. AU - Jeffree, Ross A.. AU - Copplestone, David. AU - Henry, Theodore B.. AU - Jha, Awadhesh N.. PY - 2011/9/1. Y1 - 2011/9/1. N2 - Understanding uptake and deputation of radionuclides in organisms is necessary to relate exposure to radiation dose and ultimately to biological effects. We investigated uptake and depuration of a mixture of radionuclides to link bioaccumulation with radiation dose in zebrafish, Danio rerio. Adult zebrafish were exposed to radionuclides ((54)Mn, (60)Co, (65)Zn, (75)Se, (109)Cd, (110m)Ag, (134)Cs and (241)Am) at tracer levels ((65)Zn,(109)Cd,(110m)Ag,(54)Mn,(60)Co,(241)Am,(134)Cs (range: 175-8 Bq g(1)). After dietary exposure the order of radionuclide activity concentration in tissues (Bq g(-1)) was: (65)Zn,(60)Co,(75)Se,(109)Cd,(110m)Ag,(241)Am,(54)Mn,(134)Cs (range: 91-1 Bq g(-1)). ...

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