WorldWideScience

Sample records for additional dose assessment

  1. Additional dose assessment from the activation of high-energy linear accelerators used in radiation therapy

    Directory of Open Access Journals (Sweden)

    Ateia Embarka

    2008-01-01

    Full Text Available It is well known that medical linear accelerators generate activation products when operated above certain electron (photon energies. The aim of the present work is to assess the activation behavior of a medium-energy radiotherapy linear accelerator by applying in situ gamma-ray spectrometry and dose measurements, and to estimate the additional dose to radiotherapy staff on the basis of these results. Spectral analysis was performed parallel to dose rate measurements in the isocenter of the linear accelerator, immediately after the termination of irradiation. The following radioisotopes were detected by spectral analysis: 28Al, 62Cu, 56Mn, 64Cu, 187W, and 57Ni. The short-lived isotopes such as 28Al and 62Cu are the most important factors of the clinical routine, while the contribution to the radiation dose of medium-lived isotopes such as 56Mn, 57Ni, 64Cu, and 187W increases during the working day. Measured dose rates at the isocenter ranged from 2.2 µSv/h to 10 µSv/h in various measuring points of interest for the members of the radiotherapy staff. Within the period of 10 minutes, the dose rate decreased to values of 0.8 µSv/h. According to actual workloads in radiotherapy departments, a realistic exposure scenario was set, resulting in a maximal additional annual whole body dose to the radiotherapy staff of about 3.5 mSv.

  2. "The Dose Makes the Poison": Informing Consumers About the Scientific Risk Assessment of Food Additives.

    Science.gov (United States)

    Bearth, Angela; Cousin, Marie-Eve; Siegrist, Michael

    2016-01-01

    Intensive risk assessment is required before the approval of food additives. During this process, based on the toxicological principle of "the dose makes the poison,ˮ maximum usage doses are assessed. However, most consumers are not aware of these efforts to ensure the safety of food additives and are therefore sceptical, even though food additives bring certain benefits to consumers. This study investigated the effect of a short video, which explains the scientific risk assessment and regulation of food additives, on consumers' perceptions and acceptance of food additives. The primary goal of this study was to inform consumers and enable them to construct their own risk-benefit assessment and make informed decisions about food additives. The secondary goal was to investigate whether people have different perceptions of food additives of artificial (i.e., aspartame) or natural origin (i.e., steviolglycoside). To attain these research goals, an online experiment was conducted on 185 Swiss consumers. Participants were randomly assigned to either the experimental group, which was shown a video about the scientific risk assessment of food additives, or the control group, which was shown a video about a topic irrelevant to the study. After watching the video, the respondents knew significantly more, expressed more positive thoughts and feelings, had less risk perception, and more acceptance than prior to watching the video. Thus, it appears that informing consumers about complex food safety topics, such as the scientific risk assessment of food additives, is possible, and using a carefully developed information video is a successful strategy for informing consumers.

  3. Assessment of the Annual Additional Effective Doses amongst Minamisoma Children during the Second Year after the Fukushima Daiichi Nuclear Power Plant Disaster.

    Science.gov (United States)

    Tsubokura, Masaharu; Kato, Shigeaki; Morita, Tomohiro; Nomura, Shuhei; Kami, Masahiro; Sakaihara, Kikugoro; Hanai, Tatsuo; Oikawa, Tomoyoshi; Kanazawa, Yukio

    2015-01-01

    An assessment of the external and internal radiation exposure levels, which includes calculation of effective doses from chronic radiation exposure and assessment of long-term radiation-related health risks, has become mandatory for residents living near the nuclear power plant in Fukushima, Japan. Data for all primary and secondary children in Minamisoma who participated in both external and internal screening programs were employed to assess the annual additional effective dose acquired due to the Fukushima Daiichi nuclear power plant disaster. In total, 881 children took part in both internal and external radiation exposure screening programs between 1st April 2012 to 31st March 2013. The level of additional effective doses ranged from 0.025 to 3.49 mSv/year with the median of 0.70 mSv/year. While 99.7% of the children (n = 878) were not detected with internal contamination, 90.3% of the additional effective doses was the result of external radiation exposure. This finding is relatively consistent with the doses estimated by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The present study showed that the level of annual additional effective doses among children in Minamisoma has been low, even after the inter-individual differences were taken into account. The dose from internal radiation exposure was negligible presumably due to the success of contaminated food control.

  4. Utirik Atoll Dose Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W.L.; Conrado, C.L.; Bogen, K.T

    1999-10-06

    On March 1, 1954, radioactive fallout from the nuclear test at Bikini Atoll code-named BRAVO was deposited on Utirik Atoll which lies about 187 km (300 miles) east of Bikini Atoll. The residents of Utirik were evacuated three days after the fallout started and returned to their atoll in May 1954. In this report we provide a final dose assessment for current conditions at the atoll based on extensive data generated from samples collected in 1993 and 1994. The estimated population average maximum annual effective dose using a diet including imported foods is 0.037 mSv y{sup -1} (3.7 mrem y{sup -1}). The 95% confidence limits are within a factor of three of their population average value. The population average integrated effective dose over 30-, 50-, and 70-y is 0.84 mSv (84, mrem), 1.2 mSv (120 mrem), and 1.4 mSv (140 mrem), respectively. The 95% confidence limits on the population-average value post 1998, i.e., the 30-, 50-, and 70-y integral doses, are within a factor of two of the mean value and are independent of time, t, for t > 5 y. Cesium-137 ({sup 137}Cs) is the radionuclide that contributes most of this dose, mostly through the terrestrial food chain and secondarily from external gamma exposure. The dose from weapons-related radionuclides is very low and of no consequence to the health of the population. The annual background doses in the U. S. and Europe are 3.0 mSv (300 mrem), and 2.4 mSv (240 mrem), respectively. The annual background dose in the Marshall Islands is estimated to be 1.4 mSv (140 mrem). The total estimated combined Marshall Islands background dose plus the weapons-related dose is about 1.5 mSv y{sup -1} (150 mrem y{sup -1}) which can be directly compared to the annual background effective dose of 3.0 mSv y{sup -1} (300 mrem y{sup -1}) for the U. S. and 2.4 mSv y{sup -1} (240 mrem y{sup -1}) for Europe. Moreover, the doses listed in this report are based only on the radiological decay of {sup 137}Cs (30.1 y half-life) and other

  5. Assessment of internal doses

    CERN Document Server

    Rahola, T; Falk, R; Isaksson, M; Skuterud, L

    2002-01-01

    There is a definite need for training in dose calculation. Our first course was successful and was followed by a second, both courses were fully booked. An example of new tools for software products for bioassay analysis and internal dose assessment is the Integrated Modules for Bioassay Analysis (IMBA) were demonstrated at the second course. This suite of quality assured code modules have been adopted in the UK as the standard for regulatory assessment purposes. The intercomparison measurements are an important part of the Quality Assurance work. In what is known as the sup O utside workers ' directive it is stated that the internal dose measurements shall be included in the European Unions supervision system for radiation protection. The emergency preparedness regarding internal contamination was much improved by the training with and calibration of handheld instruments from participants' laboratories. More improvement will be gained with the handbook giving practical instructions on what to do in case of e...

  6. Role of sulfite additives in wine induced asthma: single dose and cumulative dose studies

    OpenAIRE

    Vally, H; Thompson, P.

    2001-01-01

    BACKGROUND—Wine appears to be a significant trigger for asthma. Although sulfite additives have been implicated as a major cause of wine induced asthma, direct evidence is limited. Two studies were undertaken to assess sulfite reactivity in wine sensitive asthmatics. The first study assessed sensitivity to sulfites in wine using a single dose sulfited wine challenge protocol followed by a double blind, placebo controlled challenge. In the second study a cumulative dose su...

  7. Dose assessments for SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Avila, Rodolfo; Ekstroem, Per-Anders; Cruz, Idalmis de la (Facilia AB, Bromma (Sweden))

    2008-06-15

    Following a review by the Swedish regulatory authorities of the safety analysis of the SFR 1 disposal facility for low and intermediate level waste, SKB has prepared an updated safety analysis, SAR-08. This report presents estimations of annual doses to the most exposed groups from potential radionuclide releases from the SFR 1 repository for a number of calculation cases, selected using a systematic approach for identifying relevant scenarios for the safety analysis. The dose estimates can be used for demonstrating that the long term safety of the repository is in compliance with the regulatory requirements. In particular, the mean values of the annual doses can be used to estimate the expected risks to the most exposed individuals, which can then be compared with the regulatory risk criteria for human health. The conversion from doses to risks is performed in the main report. For one scenario however, where the effects of an earthquake taking place close to the repository are analysed, risk calculations are presented in this report. In addition, prediction of concentrations of radionuclides in environmental media, such as water and soil, are compared with concentration limits suggested by the Erica-project as a base for estimating potential effects on the environment. The assessment of the impact on non-human biota showed that the potential impact is negligible. Committed collective dose for an integration period of 10,000 years for releases occurring during the first thousand years after closure are also calculated. The collective dose commitment was estimated to be 8 manSv. The dose calculations were carried out for a period of 100,000 years, which was sufficient to observe peak doses in all scenarios considered. Releases to the landscape and to a well were considered. The peaks of the mean annual doses from releases to the landscape are associated with C-14 releases to a future lake around year 5,000 AD. In the case of releases to a well, the peak annual doses

  8. Dose assessments for SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Avila, Rodolfo; Ekstroem, Per-Anders; Cruz, Idalmis de la (Facilia AB, Bromma (Sweden))

    2008-06-15

    Following a review by the Swedish regulatory authorities of the safety analysis of the SFR 1 disposal facility for low and intermediate level waste, SKB has prepared an updated safety analysis, SAR-08. This report presents estimations of annual doses to the most exposed groups from potential radionuclide releases from the SFR 1 repository for a number of calculation cases, selected using a systematic approach for identifying relevant scenarios for the safety analysis. The dose estimates can be used for demonstrating that the long term safety of the repository is in compliance with the regulatory requirements. In particular, the mean values of the annual doses can be used to estimate the expected risks to the most exposed individuals, which can then be compared with the regulatory risk criteria for human health. The conversion from doses to risks is performed in the main report. For one scenario however, where the effects of an earthquake taking place close to the repository are analysed, risk calculations are presented in this report. In addition, prediction of concentrations of radionuclides in environmental media, such as water and soil, are compared with concentration limits suggested by the Erica-project as a base for estimating potential effects on the environment. The assessment of the impact on non-human biota showed that the potential impact is negligible. Committed collective dose for an integration period of 10,000 years for releases occurring during the first thousand years after closure are also calculated. The collective dose commitment was estimated to be 8 manSv. The dose calculations were carried out for a period of 100,000 years, which was sufficient to observe peak doses in all scenarios considered. Releases to the landscape and to a well were considered. The peaks of the mean annual doses from releases to the landscape are associated with C-14 releases to a future lake around year 5,000 AD. In the case of releases to a well, the peak annual doses

  9. Irrigation in dose assessments models

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla; Barkefors, Catarina [Studsvik RadWaste AB, Nykoeping (Sweden)

    2004-05-01

    SKB has carried out several safety analyses for repositories for radioactive waste, one of which was SR 97, a multi-site study concerned with a future deep bedrock repository for high-level waste. In case of future releases due to unforeseen failure of the protective multiple barrier system, radionuclides may be transported with groundwater and may reach the biosphere. Assessments of doses have to be carried out with a long-term perspective. Specific models are therefore employed to estimate consequences to man. It has been determined that the main pathway for nuclides from groundwater or surface water to soil is via irrigation. Irrigation may cause contamination of crops directly by e.g. interception or rain-splash, and indirectly via root-uptake from contaminated soil. The exposed people are in many safety assessments assumed to be self-sufficient, i.e. their food is produced locally where the concentration of radionuclides may be the highest. Irrigation therefore plays an important role when estimating consequences. The present study is therefore concerned with a more extensive analysis of the role of irrigation for possible future doses to people living in the area surrounding a repository. Current irrigation practices in Sweden are summarised, showing that vegetables and potatoes are the most common crops for irrigation. In general, however, irrigation is not so common in Sweden. The irrigation model used in the latest assessments is described. A sensitivity analysis is performed showing that, as expected, interception of irrigation water and retention on vegetation surfaces are important parameters. The parameters used to describe this are discussed. A summary is also given how irrigation is proposed to be handled in the international BIOMASS (BIOsphere Modelling and ASSessment) project and in models like TAME and BIOTRAC. Similarities and differences are pointed out. Some numerical results are presented showing that surface contamination in general gives the

  10. Radiological dose assessment for vault storage concepts

    Energy Technology Data Exchange (ETDEWEB)

    Richard, R.F.

    1997-02-25

    This radiological dose assessment presents neutron and photon dose rates in support of project W-460. Dose rates are provided for a single 3013 container, the ``infloor`` storage vault concept, and the ``cubicle`` storage vault concept.

  11. A four-step approach to evaluate mixtures for consistency with dose addition.

    Science.gov (United States)

    Hertzberg, Richard C; Pan, Yi; Li, Ruosha; Haber, Lynne T; Lyles, Robert H; Herr, David W; Moser, Virginia C; Simmons, Jane Ellen

    2013-11-16

    Mixture risk assessment is often hampered by the lack of dose-response information on the mixture being assessed, forcing reliance on component formulas such as dose addition. We present a four-step approach for evaluating chemical mixture data for consistency with dose addition for use in supporting a component based mixture risk assessment. Following the concepts in the U.S. EPA mixture risk guidance (U.S. EPA, 2000a,b), toxicological interaction for a defined mixture (all components known) is departure from a clearly articulated definition of component additivity. For the common approach of dose additivity, the EPA guidance identifies three desirable characteristics, foremost of which is that the component chemicals are toxicologically similar. The other two characteristics are empirical: the mixture components have toxic potencies that are fixed proportions of each other (throughout the dose range of interest), and the mixture dose term in the dose additive prediction formula, which we call the combined prediction model (CPM), can be represented by a linear combination of the component doses. A consequent property of the proportional toxic potencies is that the component chemicals must share a common dose-response model, where only the dose coefficients depend on the chemical components. A further consequence is that the mixture data must be described by the same mathematical function ("mixture model") as the components, but with a distinct coefficient for the total mixture dose. The mixture response is predicted from the component dose-response curves by using the dose additive CPM and the prediction is then compared with the observed mixture results. The four steps are to evaluate: (1) toxic proportionality by determining how well the CPM matches the single chemical models regarding mean and variance; (2) fit of the mixture model to the mixture data; (3) agreement between the mixture data and the CPM prediction; and (4) consistency between the CPM and the

  12. Calculational Tool for Skin Contamination Dose Assessment

    CERN Document Server

    Hill, R L

    2002-01-01

    Spreadsheet calculational tool was developed to automate the calculations preformed for dose assessment of skin contamination. This document reports on the design and testing of the spreadsheet calculational tool.

  13. An updated dose assessment for Rongelap Island

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W.L.; Conrado, C.L.; Bogen, K.T.

    1994-07-01

    We have updated the radiological dose assessment for Rongelap Island at Rongelap Atoll using data generated from field trips to the atoll during 1986 through 1993. The data base used for this dose assessment is ten fold greater than that available for the 1982 assessment. Details of each data base are presented along with details about the methods used to calculate the dose from each exposure pathway. The doses are calculated for a resettlement date of January 1, 1995. The maximum annual effective dose is 0.26 mSv y{sup {minus}1} (26 mrem y{sup {minus}1}). The estimated 30-, 50-, and 70-y integral effective doses are 0.0059 Sv (0.59 rem), 0.0082 Sv (0.82 rem), and 0.0097 Sv (0.97 rem), respectively. More than 95% of these estimated doses are due to 137-Cesium ({sup 137}Cs). About 1.5% of the estimated dose is contributed by 90-Strontium ({sup 90}Sr), and about the same amount each by 239+240-Plutonium ({sup 239+240}PU), and 241-Americium ({sup 241}Am).

  14. Assessment of the skin dose for aircrew.

    Science.gov (United States)

    Meier, Matthias M; Matthiä, Daniel

    2017-03-02

    Epidemiological studies are a useful instrument for investigating the influence of environmental factors on human health. In this context, the determination and quantification of the corresponding exposure is a demanding challenge. With regard to the investigation of the potential health effects in aircrew due to cosmic radiation, their occupational exposure at aviation altitudes is usually assessed in terms of the radiation protection quantity effective dose, which is stored in and available from official dose registers in many countries. However, when biological effects on a particular organ are investigated, knowledge of the corresponding exposure of that particular organ is necessary. In this study, we investigate the differences between the skin dose and the effective dose for the exposure of aircrew to cosmic radiation using a mathematical model for the radiation field at aviation altitudes. Furthermore, we present a method to deduce skin dose values from the officially registered effective doses.

  15. Assessing dose rate distributions in VMAT plans

    Science.gov (United States)

    Mackeprang, P.-H.; Volken, W.; Terribilini, D.; Frauchiger, D.; Zaugg, K.; Aebersold, D. M.; Fix, M. K.; Manser, P.

    2016-04-01

    Dose rate is an essential factor in radiobiology. As modern radiotherapy delivery techniques such as volumetric modulated arc therapy (VMAT) introduce dynamic modulation of the dose rate, it is important to assess the changes in dose rate. Both the rate of monitor units per minute (MU rate) and collimation are varied over the course of a fraction, leading to different dose rates in every voxel of the calculation volume at any point in time during dose delivery. Given the radiotherapy plan and machine specific limitations, a VMAT treatment plan can be split into arc sectors between Digital Imaging and Communications in Medicine control points (CPs) of constant and known MU rate. By calculating dose distributions in each of these arc sectors independently and multiplying them with the MU rate, the dose rate in every single voxel at every time point during the fraction can be calculated. Independently calculated and then summed dose distributions per arc sector were compared to the whole arc dose calculation for validation. Dose measurements and video analysis were performed to validate the calculated datasets. A clinical head and neck, cranial and liver case were analyzed using the tool developed. Measurement validation of synthetic test cases showed linac agreement to precalculated arc sector times within  ±0.4 s and doses  ±0.1 MU (one standard deviation). Two methods for the visualization of dose rate datasets were developed: the first method plots a two-dimensional (2D) histogram of the number of voxels receiving a given dose rate over the course of the arc treatment delivery. In similarity to treatment planning system display of dose, the second method displays the dose rate as color wash on top of the corresponding computed tomography image, allowing the user to scroll through the variation over time. Examining clinical cases showed dose rates spread over a continuous spectrum, with mean dose rates hardly exceeding 100 cGy min-1 for conventional

  16. Metrics, Dose, and Dose Concept: The Need for a Proper Dose Concept in the Risk Assessment of Nanoparticles

    Directory of Open Access Journals (Sweden)

    Myrtill Simkó

    2014-04-01

    Full Text Available In order to calculate the dose for nanoparticles (NP, (i relevant information about the dose metrics and (ii a proper dose concept are crucial. Since the appropriate metrics for NP toxicity are yet to be elaborated, a general dose calculation model for nanomaterials is not available. Here we propose how to develop a dose assessment model for NP in analogy to the radiation protection dose calculation, introducing the so-called “deposited and the equivalent dose”. As a dose metric we propose the total deposited NP surface area (SA, which has been shown frequently to determine toxicological responses e.g. of lung tissue. The deposited NP dose is proportional to the total surface area of deposited NP per tissue mass, and takes into account primary and agglomerated NP. By using several weighting factors the equivalent dose additionally takes into account various physico-chemical properties of the NP which are influencing the biological responses. These weighting factors consider the specific surface area, the surface textures, the zeta-potential as a measure for surface charge, the particle morphology such as the shape and the length-to-diameter ratio (aspect ratio, the band gap energy levels of metal and metal oxide NP, and the particle dissolution rate. Furthermore, we discuss how these weighting factors influence the equivalent dose of the deposited NP.

  17. ESR dose assessment in irradiated chicken legs

    Energy Technology Data Exchange (ETDEWEB)

    Bordi, F. [II Universita, Rome (Italy). Dipartimento di Medicina Interna; Fattibene, P.; Onori, S.; Pantaloni, M. [Istituto Superiore di Santia, Rome (Italy)]|[Istituto Nazionale di Fisica Nucleare, Rome (Italy). Sezione Sanita

    1994-05-01

    The electron spin resonance technique has received a wide consensus for dose assessment in irradiated chicken bone. Nevertheless, some practical problems are still open like the most suitable mathematical expression to be used for dose evaluation with the re-irradiation method. In the present paper the linear and exponential approximations were analyzed using 40 bone chicken samples and a reproducible readout procedure. The results suggested the use of the exponential dose-effect relationship and gave some indications on the procedure to be practically adopted. (author).

  18. Intraoperative fluoroscopic dose assessment in prostate brachytherapy patients.

    Science.gov (United States)

    Reed, Daniel R; Wallner, Kent E; Narayanan, Sreeram; Sutlief, Steve G; Ford, Eric C; Cho, Paul S

    2005-09-01

    To evaluate a fluoroscopy-based intraoperative dosimetry system to guide placement of additional sources to underdosed areas, and perform computed tomography (CT) verification. Twenty-six patients with prostate carcinoma treated with either I-125 or Pd-103 brachytherapy at the Puget Sound VA using intraoperative postimplant dosimetry were analyzed. Implants were performed by standard techniques. After completion of the initial planned brachytherapy procedure, the initial fluoroscopic intraoperative dose reconstruction analysis (I-FL) was performed with three fluoroscopic images acquired at 0 (AP), +15, and -15 degrees. Automatic seed identification was performed and the three-dimensional (3D) seed coordinates were computed and imported into VariSeed for dose visualization. Based on a 3D assessment of the isodose patterns additional seeds were implanted, and the final fluoroscopic intraoperative dose reconstruction was performed (FL). A postimplant computed tomography (CT) scan was obtained after the procedure and dosimetric parameters and isodose patterns were analyzed and compared. An average of 4.7 additional seeds were implanted after intraoperative analysis of the dose coverage (I-FL), and a median of 5 seeds. After implantation of additional seeds the mean V100 increased from 89% (I-FL) to 92% (FL) (p sources to supplement inadequately dosed areas within the prostate gland. Additionally, guided implantation of additional source, can significantly improve V100s and D90s, without significantly increasing rectal doses.

  19. A Novel Approach for Evaluating Carbamate Mixtures for Dose Additivity

    Science.gov (United States)

    Two mathematical approaches were used to test the hypothesis ofdose-addition for a binary and a seven-chemical mixture ofN-methyl carbamates, toxicologically similar chemicals that inhibit cholinesterase (ChE). In the more novel approach, mixture data were not included in the ana...

  20. Additional effective dose by patients undergoing NAI-131 capsules therapy

    Energy Technology Data Exchange (ETDEWEB)

    Orlic, M.; Jovanovic, M.; Spasic Jokic, V.; Cuknic, O.; Ilic, Z.; Vranjes Djuric, S. [VINCA - Institute of Nuclear Sciences, Belgrade, Serbia and Montenegro (Yugoslavia)

    2006-07-01

    Capsules or solutions containing Na{sup 131}I are indicated for the therapy of some thyroid carcinomas such as functioning metastatic papillary or follicular carcinoma of the thyroid; and for the treatment of hyperthyroidism (diffuse toxic goiter and single or multiple toxic nodular goiter). The recommended dosage ranges of Na{sup 131}I capsules or solution for the therapy of the average patient (70 kg) are: (3.7-5.55) GBq for ablation of normal thyroid tissue; (3.7-7.4) GBq for subsequent treatments; a (148-370) MBq for hyperthyroidism. The purpose of this paper is to calculate effective dose as a result of iodine-131 capsules remaining in stomach before absorption starts. This result can determine the disadvantage of capsule versus solution containing sodium iodine-131 (Na{sup 131}I) in radionuclide therapy application from radiation protection point of view. The Monte Carlo code MCNP4b was used to model transport of gamma and beta particles emitted by radionuclide {sup 131}I treated as a point source at the bottom of stomach. Absorbed energy per unit transformation in stomach and surrounding organs has been calculated. (authors)

  1. A mathematical approach to optimal selection of dose values in the additive dose method of ERP dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, R.B.; Haskell, E.H.; Kenner, G.H. [Utah Univ., Salt Lake City, UT (United States)

    1996-01-01

    Additive dose methods commonly used in electron paramagnetic resonance (EPR) dosimetry are time consuming and labor intensive. We have developed a mathematical approach for determining optimal spacing of applied doses and the number of spectra which should be taken at each dose level. Expected uncertainitites in the data points are assumed to be normally distributed with a fixed standard deviation and linearity of dose response is also assumed. The optimum spacing and number of points necessary for the minimal error can be estimated, as can the likely error in the resulting estimate. When low doses are being estimated for tooth enamel samples the optimal spacing is shown to be a concentration of points near the zero dose value with fewer spectra taken at a single high dose value within the range of known linearity. Optimization of the analytical process results in increased accuracy and sample throughput.

  2. Dose estimates for the solid waste performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Rittman, P.D.

    1994-08-30

    The Solid Waste Performance Assessment calculations by PNL in 1990 were redone to incorporate changes in methods and parameters since then. The ten scenarios found in their report were reduced to three, the Post-Drilling Resident, the Post-Excavation Resident, and an All Pathways Irrigator. In addition, estimates of population dose to people along the Columbia River are also included. The attached report describes the methods and parameters used in the calculations, and derives dose factors for each scenario. In addition, waste concentrations, ground water concentrations, and river water concentrations needed to reach the performance objectives of 100 mrem/yr and 500 person-rem/yr are computed. Internal dose factors from DOE-0071 were applied when computing internal dose. External dose rate factors came from the GENII Version 1.485 software package. Dose calculations were carried out on a spreadsheet. The calculations are described in detail in the report for 63 nuclides, including 5 not presently in the GENII libraries. The spreadsheet calculations were checked by comparison with GENII, as described in Appendix D.

  3. Dose assessment of aircrew using passive detectors

    Energy Technology Data Exchange (ETDEWEB)

    Hajek, M.; Berge, T.; Schoener, W.; Summerer, L.; Vana, N

    2002-07-01

    Radiation exposure of aircrew is a serious concern which has been given special emphasis in the European Council directive 96/29/Euratom. The cosmic ray induced neutron component can contribute more than 50% to the biologically relevant dose at aviation altitudes. Various computational approaches to route dose assessment, e.g. CARI, are in use nowadays and are compared with experimental data. Measurements of aircrew exposure usually involve extensive instrumentation in order to cover the whole particle spectrum and energy range present inside aircraft. Due to their small size and easy handling, thermoluminescence dosemeters represent an appropriate alternative. Previous measurements onboard aircraft applying the high-temperature ratio method with LiF:Mg,Ti dosemeters for the determination of an 'averaged' linear energy transfer of mixed radiation fields demonstrate the ability of this method to evaluate the dose equivalent, according to the Q(LET{sub (}) relationship proposed by the ICRP. Measurements with CaF{sub 2}:Tm dosemeters are currently in progress and are discussed here. (author)

  4. Peak Dose Assessment for Proposed DOE-PPPO Authorized Limits

    Energy Technology Data Exchange (ETDEWEB)

    Maldonado, Delis [Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program

    2012-06-01

    The Oak Ridge Institute for Science and Education (ORISE), a U.S. Department of Energy (DOE) prime contractor, was contracted by the DOE Portsmouth/Paducah Project Office (DOE-PPPO) to conduct a peak dose assessment in support of the Authorized Limits Request for Solid Waste Disposal at Landfill C-746-U at the Paducah Gaseous Diffusion Plant (DOE-PPPO 2011a). The peak doses were calculated based on the DOE-PPPO Proposed Single Radionuclides Soil Guidelines and the DOE-PPPO Proposed Authorized Limits (AL) Volumetric Concentrations available in DOE-PPPO 2011a. This work is provided as an appendix to the Dose Modeling Evaluations and Technical Support Document for the Authorized Limits Request for the C-746-U Landfill at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky (ORISE 2012). The receptors evaluated in ORISE 2012 were selected by the DOE-PPPO for the additional peak dose evaluations. These receptors included a Landfill Worker, Trespasser, Resident Farmer (onsite), Resident Gardener, Recreational User, Outdoor Worker and an Offsite Resident Farmer. The RESRAD (Version 6.5) and RESRAD-OFFSITE (Version 2.5) computer codes were used for the peak dose assessments. Deterministic peak dose assessments were performed for all the receptors and a probabilistic dose assessment was performed only for the Offsite Resident Farmer at the request of the DOE-PPPO. In a deterministic analysis, a single input value results in a single output value. In other words, a deterministic analysis uses single parameter values for every variable in the code. By contrast, a probabilistic approach assigns parameter ranges to certain variables, and the code randomly selects the values for each variable from the parameter range each time it calculates the dose (NRC 2006). The receptor scenarios, computer codes and parameter input files were previously used in ORISE 2012. A few modifications were made to the parameter input files as appropriate for this effort. Some of these changes

  5. Changes of radiation dose and image quality due to additional filtration material in computed radiography

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Soon Mu; Cho, Hyung Wook [Dept. of Radiological Science, The Graduate School of Catholic University of Daegu, Daegu (Korea, Republic of); Kang, Yeong Han [Dept. of Radiology, Catholic University Hospital of Daegu School of Medicine, Daegu (Korea, Republic of); Kim, Boo Soon [Dept. of Radiologicic Technology, Daegu Health College, Daegu (Korea, Republic of); Kim, Jung Su [Dept. of Bio-convergence Engineering, Korea University Graduate School, Seoul (Korea, Republic of)

    2014-12-15

    Filter absorbs low-energy X-ray to increase the average energy and reduces patient exposure dose. This study investigates if the materials of Mo and W could be used for the digital imaging device CR by conducting image assessment and dose measurement of SNR, FOM and histogram. In addition, measurement of beam quality was conducted depending on the material of the filter, and at the same time, a proper combination of filters was examined depending on the change in tube voltage (kVp). In regard to entrance skin dose, Mo filter showed the dose reduction by 42∼56%, compared to Cu filter. Moreover, Mo filter showed higher transmission dose by around 1.5 times than that of Cu filter. In image assessment, it was found that W was unsuitable to be used as a filter, whereas Mo could be used as a filter to reduce dose without decline in image quality at the tube voltage of 80 kVp or higher. As tube voltage increased, 2.0 mm Al+0.1 mm Mo almost had a similar histogram width to that of 2.0 mm Al+0.2 mm Cu. Therefore, Mo filter can be used at relatively high tube voltage of 80 kVp, 100 kVp and 120 kVp. The SNR of 2.0 mm Al+0.1 mm Mo did not show any significant difference from those of 2.0 mm Al+0.2 mm Cu and 2.0 mm Al+0.1 mm Cu. As a result, if Mo filter is used to replace Cu filter in general radiography, where 80 kVp or higher is used for digital radiation image, patient exposure dose can be reduced significantly without decline in image quality, compared to Cu filter. Therefore, it is believed that Mo filter can be applied to chest X-ray and high tube voltage X-ray in actual clinical practice.

  6. Preliminary dose assessment of the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Hull, A.P.

    1987-01-01

    From the major accident at Unit 4 of the Chernobyl nuclear power station, a plume of airborne radioactive fission products was initially carried northwesterly toward Poland, thence toward Scandinavia and into Central Europe. Reports of the levels of radioactivity in a variety of media and of external radiation levels were collected in the Department of Energy's Emergency Operations Center and compiled into a data bank. Portions of these and other data which were obtained directly from published and official reports were utilized to make a preliminary assessment of the extent and magnitude of the external dose to individuals downwind from Chernobyl. Radioactive /sup 131/I was the predominant fission product. The time of arrival of the plume and the maximum concentrations of /sup 131/I in air, vegetation and milk and the maximum reported depositions and external radiation levels have been tabulated country by country. A large amount of the total activity in the release was apparently carried to a significant elevation. The data suggest that in areas where rainfall occurred, deposition levels were from ten to one-hundred times those observed in nearby ''dry'' locations. Sufficient spectral data were obtained to establish average release fractions and to establish a reference spectra of the other nuclides in the release. Preliminary calculations indicated that the collective dose equivalent to the population in Scandinavia and Central Europe during the first year after the Chernobyl accident would be about 8 x 10/sup 6/ person-rem. From the Soviet report, it appears that a first year population dose of about 2 x 10/sup 7/ person-rem (2 x 10/sup 5/ Sv) will be received by the population who were downwind of Chernobyl within the U.S.S.R. during the accident and its subsequent releases over the following week. 32 refs., 14 figs., 20 tabs.

  7. Assessment of internal doses in emergency situations

    Energy Technology Data Exchange (ETDEWEB)

    Rahola, T.; Muikku, M. [Radiation and Nuclear Safety Authority - STUK (Finland); Falk, R.; Johansson, J. [Swedish Radiation Protection Authority - SSI (Sweden); Liland, A.; Thorshaug, S. [NRPA (Norway)

    2006-04-15

    The need for assessing internal radiation doses in emergency situations was demonstrated after accidents in Brazil, Ukraine and other countries. Lately more and more concern has been expressed regarding malevolent use of radiation and radioactive materials. The scenarios for such use are more difficult to predict than for nuclear power plant or weapons accidents. Much of the results of the work done in the IRADES project can be adopted for use in various accidental situations involving radionuclides that are not addressed in this report. If an emergency situation occurs in only one or a few of the Nordic countries, experts from the other countries could be called upon to assist in monitoring. A big advantage is then our common platform. In the Nordic countries much work has been put down on quality assurance of measurements and on training of dose assessment calculations. Attention to this was addressed at the internal dosimetry course in October 2005. Nordic emergency preparedness exercises have so far not included training of direct measurements of people in the early phase of an emergency. The aim of the IRADES project was to improve the preparedness especially for thyroid measurements. The modest financial support did not enable the participants to make big efforts but certainly acted as a much appreciated reminder of the importance of being prepared also to handle situations with malevolent use of radioactive materials. It was left to each country to decide to which extent to improve the practical skills. There is still a need for detailed national implementation plans. Measurement strategies need to be developed in each country separately taking into account national regulations, local circumstances and resources. End users of the IRADES report are the radiation protection authorities. (au)

  8. Assessment of internal doses in emergency situations

    Energy Technology Data Exchange (ETDEWEB)

    Rahola, T.; Muikku, M. [Radiation and Nuclear Safety Authority - STUK (Finland); Falk, R.; Johansson, J. [Swedish Radiation Protection Authority - SSI (Sweden); Liland, A.; Thorshaug, S. [NRPA (Norway)

    2006-04-15

    The need for assessing internal radiation doses in emergency situations was demonstrated after accidents in Brazil, Ukraine and other countries. Lately more and more concern has been expressed regarding malevolent use of radiation and radioactive materials. The scenarios for such use are more difficult to predict than for nuclear power plant or weapons accidents. Much of the results of the work done in the IRADES project can be adopted for use in various accidental situations involving radionuclides that are not addressed in this report. If an emergency situation occurs in only one or a few of the Nordic countries, experts from the other countries could be called upon to assist in monitoring. A big advantage is then our common platform. In the Nordic countries much work has been put down on quality assurance of measurements and on training of dose assessment calculations. Attention to this was addressed at the internal dosimetry course in October 2005. Nordic emergency preparedness exercises have so far not included training of direct measurements of people in the early phase of an emergency. The aim of the IRADES project was to improve the preparedness especially for thyroid measurements. The modest financial support did not enable the participants to make big efforts but certainly acted as a much appreciated reminder of the importance of being prepared also to handle situations with malevolent use of radioactive materials. It was left to each country to decide to which extent to improve the practical skills. There is still a need for detailed national implementation plans. Measurement strategies need to be developed in each country separately taking into account national regulations, local circumstances and resources. End users of the IRADES report are the radiation protection authorities. (au)

  9. Comparison of image quality and effective dose by additional filtration on digital chest tomosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kye Sun [Dept. of Dignostic Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Sung Chul [Dept. of Radiological Science, Gachon University, Sungnam (Korea, Republic of)

    2015-12-15

    The purpose of this study is to suggest proper additional filtration by comparisons patient dose and image quality among additional filters in digital chest tomosynthesis (DTS). We measured the effective dose, dose area product (DAP) by changing thickness of Cu, Al and Ni filter to compare image quality by CD curve and SNR, CNR. Cu, Al and Ni exposure dose were similar thickness 0.3 mm, 3 mm and 0.3 mm respectively. The exposure dose using filter was decreased average about 33.1% than non filter. The DAP value of 0.3 mm Ni were decreased 72.9% compared to non filter and the lowest dose among 3 filter. The effective dose of 0.3 mm Ni were decreased 48% compared to 0.102 mSv effective dose of non filter. At the result of comparison of image quality through CD curve there were similar aspect graph among Cu, Al and Ni. SNR was decreased average 19.07%, CNR was average decreased 18.17% using 3 filters. In conclusion, Ni filtration was considered to be most suitable when considered comprehensive thickness, character, sort of filter, dose reduction and image quality evaluation in DTS.

  10. CANISTER HANDLING FACILITY WORKER DOSE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    D.T. Dexheimer

    2004-02-27

    The purpose of this calculation is to estimate radiation doses received by personnel working in the Canister Handling Facility (CHF) performing operations to receive transportation casks, transfer wastes, prepare waste packages, perform associated equipment maintenance. The specific scope of work contained in this calculation covers individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation. The results of this calculation will be used to support the design of the CHF and provide occupational dose estimates for the License Application.

  11. High-dose aspirin in addition to daily low-dose aspirin decreases platelet activation in patients before and after percutaneous coronary intervention.

    Science.gov (United States)

    ten Berg, Jurriën M; Gerritsen, Wim B M; Haas, Fred J L M; Kelder, Hans C; Verheugt, Freek W A; Plokker, H W Thijs

    2002-03-01

    Activated platelets play a major role in acute vessel closure after coronary angioplasty. Although aspirin is the routine therapy during angioplasty, it only incompletely prevents acute closure. This might be due to suboptimal dosing. First, to study the effect of additional high-dose aspirin on platelet activation during coronary angioplasty. Second, to assess the potential of the new PFA-100 analyzer to evaluate the effect of different doses of aspirin in patients undergoing angioplasty. Fifty-one patients on 100 mg aspirin/day for at least 1 month were randomized to continuation of 100 mg aspirin/day only (Group A=24 patients), or to this regime plus a bolus of 1000 mg of aspirin given 1 day before angioplasty (Group B=27 patients). Results were compared with 15 controls. Platelet function was measured before angioplasty by the PFA-100 analyzer; platelet activation was measured by flow cytometry just before and 1 h after angioplasty. At baseline, Group A had significantly more activated platelets than the control group (P<.001). High-dose aspirin in Group B resulted in significantly lower platelet activation as compared with both controls (P<.001) and Group A (P<.001). During angioplasty, the number of activated platelets decreased significantly in Group A (P<.001), while there was no change in Group B (P=.6). The PFA-100 analyzer was unable to detect differences between the two treatment groups. The addition of high-dose aspirin to daily low-dose aspirin, 1 day before coronary angioplasty, significantly reduced the platelet activation state before and after intervention. The PFA-100 analyzer did not detect differences in the effect of low- versus high-dose aspirin on platelet function.

  12. Effect of an additional dose of indacaterol in COPD patients under regular treatment with indacaterol.

    Science.gov (United States)

    Cazzola, Mario; Segreti, Andrea; Stirpe, Emanuele; Puxeddu, Ermanno; Ora, Josuel; Rogliani, Paola; Matera, Maria Gabriella

    2013-01-01

    In this randomized, double-blind, crossover study, we explored the acute effects on respiratory function and safety of an additional dose of indacaterol 150 μg in stable COPD patients regularly treated with a conventional dose of indacaterol 150 μg. On two non-consecutive days, patients inhaled indacaterol 150 μg. After 180 min, they inhaled an additional dose of indacaterol 150 μg or placebo. Lung function, oxygen saturation by pulse oximetry (SpO(2)) and heart rate were measured before the first drug administration and up to 360 min thereafter. In both treatment groups, indacaterol induced a significant (P indacaterol 150 μg with the second dose of 150 μg. Indacaterol 150 μg induced a modest but significant decrease in SpO(2) up to 60 min and a second dose of indacaterol 150 μg significantly decreased the SpO(2) mean value up to 360 min. This study suggests that it is reasonable and safe to increase the dose of indacaterol in those stable COPD patients who are under regular therapy with indacaterol 150 μg from which they do not draw the maximum benefit because they are unable to perceive bronchodilation. However, only a minority of patients seem to benefit from this dose escalation, at least in terms of spirometric improvement. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Interactive Rapid Dose Assessment Model (IRDAM): reactor-accident assessment methods. Vol. 2

    Energy Technology Data Exchange (ETDEWEB)

    Poeton, R.W.; Moeller, M.P.; Laughlin, G.J.; Desrosiers, A.E.

    1983-05-01

    As part of the continuing emphasis on emergency preparedness, the US Nuclear Regulatory Commission (NRC) sponsored the development of a rapid dose assessment system by Pacific Northwest Laboratory (PNL). This system, the Interactive Rapid Dose Assessment Model (IRDAM) is a micro-computer based program for rapidly assessing the radiological impact of accidents at nuclear power plants. This document describes the technical bases for IRDAM including methods, models and assumptions used in calculations. IRDAM calculates whole body (5-cm depth) and infant thyroid doses at six fixed downwind distances between 500 and 20,000 meters. Radionuclides considered primarily consist of noble gases and radioiodines. In order to provide a rapid assessment capability consistent with the capacity of the Osborne-1 computer, certain simplifying approximations and assumptions are made. These are described, along with default values (assumptions used in the absence of specific input) in the text of this document. Two companion volumes to this one provide additional information on IRDAM. The user's Guide (NUREG/CR-3012, Volume 1) describes the setup and operation of equipment necessary to run IRDAM. Scenarios for Comparing Dose Assessment Models (NUREG/CR-3012, Volume 3) provides the results of calculations made by IRDAM and other models for specific accident scenarios.

  14. Assessment of Patient Dose from CT Examinations in Khorasan, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Bahreyni Toossi

    2013-03-01

    Full Text Available Introduction Computed Tomography scans are a very important tool for diagnosis and assessment of response to treatment in the practice of medicine. Ionizing radiation in medical imaging is undoubtedly one of the most powerful diagnostic tools in medicine. Yet, as with all medical interventions, there are potential risks in addition to the clear potential benefits. Materials and Methods Two reference dose quantities have been defined in order to promote the use of good technique in CT. These are weighted CT dose index (CTDIw in (mGy for a single slice in serial scanning or per rotation in helical scanning, and dose–length product (DLP per complete examination (mGy.cm, All measurements were performed using a pencil shaped ionization chamber introduced into polymethyl methacrylate cylindrical brain and body phantoms. This survey was performed on 7 CT scanners in Khorasan Province-Iran. Results DLP for brain, chest, abdomen and pelvic examinations had a range of 255 - 1026, 76-1277, 48-737, 69-854 mGy.cm, respectively. Conclusion The results obtained in this study show that the DLP values obtained in this province are lower than European Commission reference dose levels (EC RDL, in other words performance of all the scanners were satisfactory.

  15. An Internal Dose Assessment Associated with Personal Food Intake

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joeun; Jae, Moosung [Hanyang University, Seoul (Korea, Republic of); Hwang, Wontae [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    ICRP (International Commission on Radiological Protection), Therefore, had recommended the concept of 'Critical Group'. Recently the ICRP has recommended the use of 'Representative Person' on the new basic recommendation 103. On the other hand the U.S. NRC (Nuclear Regulatory Commission) has adopted more conservative concept, 'Maximum Exposed Individuals (MEI)' of critical Group. The dose assessment in Korea is based on MEI. Although dose assessment based on MEI is easy to receive the permission of the regulatory authority, it is not efficient. Meanwhile, the internal dose by food consumption takes an important part. Therefore, in this study, the internal dose assessment was performed in accordance with ICRP's new recommendations. The internal dose assessment was performed in accordance with ICRP's new recommendations. It showed 13.2% decreased of the annual internal dose due to gaseous effluents by replacing MEI to the concept of representative person. Also, this calculation based on new ICRP's recommendation has to be extended to all areas of individual dose assessment. Then, more accurate and efficient values might be obtained for dose assessment.

  16. Dose assessment in the criticality accident at Tokai-mura

    Energy Technology Data Exchange (ETDEWEB)

    Endo, Akira, E-mail: endo.akira3@jaea.go.j [Japan Atomic Energy Agency, Tokai-mura, Ibaraki, 319-1195 (Japan)

    2010-12-15

    The present paper reviews a dose assessment carried out after the criticality accident that occurred on September 30, 1999 at JCO in Tokai-mura, Japan. In the accident, almost all doses were caused by external exposure to neutrons and {gamma}-rays emitted upon the fission of uranium. By a joint effort of Japanese experts in radiation dosimetry, a dose assessment was performed for neighboring residents, JCO employees including 3 workers who were at the accident spot, and emergency response personnel. The dose assessment was carried out using records of dosimeters, radiation monitoring data in and around the site, analysis of biological specimens, and computer simulation techniques. It was concluded from the results of the dose assessment that deterministic effects are not expected, except for the 3 heavily exposed workers, and that the probability of stochastic effects is very small and will be undetectable.

  17. Low dose radiation risks for women surviving the a-bombs in Japan: generalized additive model.

    Science.gov (United States)

    Dropkin, Greg

    2016-11-24

    Analyses of cancer mortality and incidence in Japanese A-bomb survivors have been used to estimate radiation risks, which are generally higher for women. Relative Risk (RR) is usually modelled as a linear function of dose. Extrapolation from data including high doses predicts small risks at low doses. Generalized Additive Models (GAMs) are flexible methods for modelling non-linear behaviour. GAMs are applied to cancer incidence in female low dose subcohorts, using anonymous public data for the 1958 - 1998 Life Span Study, to test for linearity, explore interactions, adjust for the skewed dose distribution, examine significance below 100 mGy, and estimate risks at 10 mGy. For all solid cancer incidence, RR estimated from 0 - 100 mGy and 0 - 20 mGy subcohorts is significantly raised. The response tapers above 150 mGy. At low doses, RR increases with age-at-exposure and decreases with time-since-exposure, the preferred covariate. Using the empirical cumulative distribution of dose improves model fit, and capacity to detect non-linear responses. RR is elevated over wide ranges of covariate values. Results are stable under simulation, or when removing exceptional data cells, or adjusting neutron RBE. Estimates of Excess RR at 10 mGy using the cumulative dose distribution are 10 - 45 times higher than extrapolations from a linear model fitted to the full cohort. Below 100 mGy, quasipoisson models find significant effects for all solid, squamous, uterus, corpus, and thyroid cancers, and for respiratory cancers when age-at-exposure > 35 yrs. Results for the thyroid are compatible with studies of children treated for tinea capitis, and Chernobyl survivors. Results for the uterus are compatible with studies of UK nuclear workers and the Techa River cohort. Non-linear models find large, significant cancer risks for Japanese women exposed to low dose radiation from the atomic bombings. The risks should be reflected in protection standards.

  18. Development of Landscape Dose Factors for dose assessments in SR-Can

    Energy Technology Data Exchange (ETDEWEB)

    Avila, Rodolfo; Ekstroem, Per-Anders [Facilia AB, Bromma (Sweden); Kautsky, Ulrik [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    2006-08-15

    discrete events, by substituting one model by another. All radionuclides of relevance for safety assessments, except for C-14, are included in the study. Predictions of the long-term distribution in the landscape resulting from unit continuous release rates with groundwater discharges are presented for each studied radionuclide. In the main calculation variant, the releases are assumed to start at the beginning of the simulation period; and distributed between the landscape objects according to release fractions obtained from analyses of the results of the hydrological modelling. Additionally, to study the effect of the start time and location of the releases, a series of complementary simulation variants are carried out in different environmental media, comprising soils, waters and sediments. The predictions of the distribution of the radionuclides in the landscape per unit release rates are used to derive time-dependent dose conversion factors for each landscape object and for the whole landscape. To ensure that the dose to a representative member of the public in the population is identified, calculations of the dose rate are made for population groups taken to occupying a single landscape object and obtain all their resources from that object. The number of individuals that can be sustained by a landscape object is calculated for each time period by dividing the potential food production by the yearly food demand of a reference adult person. The average Dose Conversion Factors, i.e. the LDFs, for different groups in the landscape, including the most exposed group are derived, which take into account the distribution of radionuclides in the whole landscape. For each radionuclide derived maximum LDF values are given for the two studied sites, Forsmark and Laxemar. The derived maximum LDF values estimate effective dose rates to the most exposed population group per unit release of activity from a repository. By multiplying these factors by estimates of the release rates

  19. Slope of the dose-response curve: usefulness in assessing bronchial responses to inhaled histamine.

    OpenAIRE

    Cockcroft, D. W.; Berscheid, B A

    1983-01-01

    The value of determining the slope of the histamine dose-response curve, in addition to the histamine provocation concentration producing a 20% reduction in FEV1 (PC20-FEV1), was assessed by analysis of histamine dose-response curves in 40 patients selected as having a wide range of increased non-specific bronchial responsiveness to inhaled histamine. The histamine dose-response curves were found to be fit the linear curve (dose v response, mean r2 = 0.97) better than the logarithmic curve (l...

  20. Epidemiological methods for assessing dose-response and dose-effect relationships

    DEFF Research Database (Denmark)

    Kjellström, Tord; Grandjean, Philippe

    2007-01-01

    of the Toxic Effects of Metals Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Chromium Cobalt Copper Gallium and Semiconductor Compounds Germanium Indium Iron Lead Manganese Mercury Molybdenum Nickel Palladium Platinum Selenium Silver Tellurium Thallium Tin Titanium Tungsten Uranium Vanadium Zinc...... and their compounds. An entirely new structure and illustrations represent the vast array of advancements made since the last edition. Special emphasis has been placed on the toxic effects in humans with chapters on the diagnosis, treatment and prevention of metal poisoning. This up-to-date reference provides easy...... Selected Molecular Mechanisms of Metal Toxicity and Carcinogenicity General Considerations of Dose-Effect and Dose-Response Relationships Interactions in Metal Toxicology Epidemiological Methods for Assessing Dose-Response and Dose-Effect Relationships Essential Metals: Assessing Risks from Deficiency...

  1. Estradiol valerate and alcohol intake: dose-response assessments

    Science.gov (United States)

    Quirarte, Gina L; Reid, Larry D; de la Teja, I Sofía Ledesma; Reid, Meta L; Sánchez, Marco A; Díaz-Trujillo, Arnulfo; Aguilar-Vazquez, Azucena; Prado-Alcalá, Roberto A

    2007-01-01

    Background An injection of estradiol valerate (EV) provides estradiol for a prolonged period. Recent research indicates that a single 2.0 mg injection of EV modifies a female rat's appetite for alcoholic beverages. This research extends the initial research by assessing 8 doses of EV (from .001 to 2.0 mg/female rat), as well assessing the effects of 2.0 mg EV in females with ovariectomies. Results With the administration of EV, there was a dose-related loss of bodyweight reaching the maximum loss, when it occurred, at about 4 days after injections. Subsequently, rats returned to gaining weight regularly. Of the doses tested, only the 2.0 mg dose produced a consistent increase in intake of ethanol during the time previous research indicated that the rats would show enhanced intakes. There was, however, a dose-related trend for smaller doses to enhance intakes. Rats with ovariectomies showed a similar pattern of effects, to intact rats, with the 2 mg dose. After extensive histories of intake of alcohol, both placebo and EV-treated females had estradiol levels below the average measured in females without a history of alcohol-intake. Conclusion The data support the conclusion that pharmacological doses of estradiol can produce enduring changes that are manifest as an enhanced appetite for alcoholic beverages. The effect can occur among females without ovaries. PMID:17335585

  2. Development of a real-time radiological dose assessment system

    Energy Technology Data Exchange (ETDEWEB)

    Han, Moon Hee; Lee, Young Bok; Kim, Eun Han; Suh, Kyung Suk; Hwang, Won Tae; Choi, Young Gil

    1997-07-01

    A radiological dose assessment system named FADAS has been developed. This system is necessary to estimated the radiological consequences against a nuclear accident. Mass-consistent wind field module was adopted for the generation of wind field over the whole domain using the several measured wind data. Random-walk dispersion module is used for the calculation of the distribution of radionuclides in the atmosphere. And volume-equivalent numerical integration method has been developed for the assessment of external gamma exposure given from a randomly distributed radioactive materials and a dose data library has been made for rapid calculation. Field tracer experiments have been carried out for the purpose of analyzing the site-specific meteorological characteristics and increasing the accuracy of wind field generation and atmospheric dispersion module of FADAS. At first, field tracer experiment was carried out over flat terrain covered with rice fields using the gas samplers which were designed and manufactured by the staffs of KAERI. The sampled gas was analyzed using gas chromatograph. SODAR and airsonde were used to measure the upper wind. Korean emergency preparedness system CARE was integrated at Kori 4 nuclear power plants in 1995. One of the main functions of CARE is to estimate the radiological dose. The developed real-time dose assessment system FADAS was adopted in CARE as a tool for the radiological dose assessment. (author). 79 refs., 52 tabs., 94 figs.

  3. Additional benefit of higher dose green tea in lowering postprandial blood glucose

    Directory of Open Access Journals (Sweden)

    Rita Lahirin

    2015-07-01

    Full Text Available Background: Green tea contains catechins that have inhibitory effects on amylase, sucrase, and sodium-dependent glucose transporter (SGLT which result in lowering of postprandial blood glucose (PBG. This beneficial effect has been widely demonstrated using the usual dose (UD of green tea preparation. Our study was aimed to explore futher lowering of PBG using high dose (HD of green tea in healthy adolescents.Methods: 24 subjects received 100 mL infusion of either 0.67 or 3.33 grams of green tea with test meal. Fasting, PBG at 30, 60, 120 minutes were measured. Subjects were cross-overed after wash out. PBG and its incremental area under the curve (IAUC difference between groups were analyzed with paired T-test. Cathecin contents of tea were measured using high-performance liquid chromatography (HPLC.Results: The PBG of HD group was lower compared to UD (at 60 minutes =113.70 ± 13.20 vs 124.16 ± 8.17 mg/dL, p = 0.005; at 120 minutes = 88.95 ± 6.13 vs 105.25 ± 13.85 mg/dL, p < 0.001. The IAUC of HD was also found to be lower compared to UD (2055.0 vs 3411.9 min.mg/dL, p < 0.001.Conclusion: Additional benefit of lowering PBG can be achieved by using higher dose of green tea. This study recommends preparing higher dose of green tea drinks for better control of PBG.

  4. Maternal and neonatal outcomes following additional doses of vaginal prostaglandin E2 for induction of labour: a retrospective cohort study.

    Science.gov (United States)

    Ayaz, Huma; Black, Mairead; Madhuvrata, Priya; Shetty, Ashalatha

    2013-10-01

    To assess maternal and neonatal outcomes following the use of additional doses of vaginal prostaglandins (PGE2) above the recommended dose for induction of labour in post-dates pregnancies. Retrospective cohort study set in Aberdeen Maternity Hospital, Aberdeen, UK. A total of 3514 nulliparous women with labour induced with vaginal PGE2 (3mg tablet or 2mg gel) for a post-dates singleton pregnancy from January 1994 to December 2009 were included. Women receiving≤2 doses of PGE2 were compared with those receiving>2 doses (maximum 5 doses). Binary logistic regression was used to calculate odds ratios (OR) with 95% confidence intervals (CI). Primary outcomes included mode of delivery, terbutaline use, indication for CS, postpartum haemorrhage, neonatal unit admission, and Apgar scorelabour (11.4% vs. 1.9%, OR 4.1, 95% CI 1.3-13.2) or lack of progress in labour (37% vs. 17%, OR 2.8, 95% CI 2.3-3.4), but not for fetal concerns (8.2% vs. 8.8% OR 0.9, 95% CI 0.7-1.3). Terbutaline use and postpartum haemorrhage was no more likely (0.7% vs. 0.9% OR 0.6 95% CI 0.3-1.5 and 19.8% vs. 18.9% OR1.01, 95% CI 0.97-1.06 respectively). Apgar scorelabour was not associated with increased maternal or neonatal morbidity and almost half of these women achieved a vaginal delivery. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  5. Assessment of dose measurement uncertainty using RisøScan

    DEFF Research Database (Denmark)

    Helt-Hansen, J.; Miller, A.

    2006-01-01

    The dose measurement uncertainty of the dosimeter system RisoScan, office scanner and Riso B3 dosimeters has been assessed by comparison with spectrophotometer measurements of the same dosimeters. The reproducibility and the combined uncertainty were found to be approximately 2% and 4%, respectiv...

  6. Radiological assessment. A textbook on environmental dose analysis

    Energy Technology Data Exchange (ETDEWEB)

    Till, J.E.; Meyer, H.R. (eds.)

    1983-09-01

    Radiological assessment is the quantitative process of estimating the consequences to humans resulting from the release of radionuclides to the biosphere. It is a multidisciplinary subject requiring the expertise of a number of individuals in order to predict source terms, describe environmental transport, calculate internal and external dose, and extrapolate dose to health effects. Up to this time there has been available no comprehensive book describing, on a uniform and comprehensive level, the techniques and models used in radiological assessment. Radiological Assessment is based on material presented at the 1980 Health Physics Society Summer School held in Seattle, Washington. The material has been expanded and edited to make it comprehensive in scope and useful as a text. Topics covered include (1) source terms for nuclear facilities and Medical and Industrial sites; (2) transport of radionuclides in the atmosphere; (3) transport of radionuclides in surface waters; (4) transport of radionuclides in groundwater; (5) terrestrial and aquatic food chain pathways; (6) reference man; a system for internal dose calculations; (7) internal dosimetry; (8) external dosimetry; (9) models for special-case radionuclides; (10) calculation of health effects in irradiated populations; (11) evaluation of uncertainties in environmental radiological assessment models; (12) regulatory standards for environmental releases of radionuclides; (13) development of computer codes for radiological assessment; and (14) assessment of accidental releases of radionuclides.

  7. Models for dose assessments. Modules for various biosphere types

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, U.; Nordlinder, S.; Aggeryd, I. [Studsvik Eco and Safety AB, Nykoeping (Sweden)

    1999-12-01

    The main objective of this study was to provide a basis for illustrations of yearly dose rates to the most exposed individual from hypothetical leakages of radionuclides from a deep bedrock repository for spent nuclear fuel and other radioactive waste. The results of this study will be used in the safety assessment SR 97 and in a study on the design and long-term safety for a repository planned to contain long-lived low and intermediate level waste. The repositories will be designed to isolate the radionuclides for several hundred thousands of years. In the SR 97 study, however, hypothetical scenarios for leakage are postulated. Radionuclides are hence assumed to be transported in the geosphere by groundwater, and probably discharge into the biosphere. This may occur in several types of ecosystems. A number of categories of such ecosystems were identified, and turnover of radionuclides was modelled separately for each ecosystem. Previous studies had focused on generic models for wells, lakes and coastal areas. These models were, in this study, developed further to use site-specific data. In addition, flows of groundwater, containing radionuclides, to agricultural land and peat bogs were considered. All these categories are referred to as modules in this report. The forest ecosystems were not included, due to a general lack of knowledge of biospheric processes in connection with discharge of groundwater in forested areas. Examples of each type of module were run with the assumption of a continuous annual release into the biosphere of 1 Bq for each radionuclide during 10 000 years. The results are presented as ecosystem specific dose conversion factors (EDFs) for each nuclide at the year 10 000, assuming stationary ecosystems and prevailing living conditions and habits. All calculations were performed with uncertainty analyses included. Simplifications and assumptions in the modelling of biospheric processes are discussed. The use of modules may be seen as a step

  8. TSD-DOSE: A radiological dose assessment model for treatment, storage, and disposal facilities

    Energy Technology Data Exchange (ETDEWEB)

    Pfingston, M.; Arnish, J.; LePoire, D.; Chen, S.-Y.

    1998-10-14

    Past practices at US Department of Energy (DOE) field facilities resulted in the presence of trace amounts of radioactive materials in some hazardous chemical wastes shipped from these facilities. In May 1991, the DOE Office of Waste Operations issued a nationwide moratorium on shipping all hazardous waste until procedures could be established to ensure that only nonradioactive hazardous waste would be shipped from DOE facilities to commercial treatment, storage, and disposal (TSD) facilities. To aid in assessing the potential impacts of shipments of mixed radioactive and chemically hazardous wastes, a radiological assessment computer model (or code) was developed on the basis of detailed assessments of potential radiological exposures and doses for eight commercial hazardous waste TSD facilities. The model, called TSD-DOSE, is designed to incorporate waste-specific and site-specific data to estimate potential radiological doses to on-site workers and the off-site public from waste-handling operations at a TSD facility. The code is intended to provide both DOE and commercial TSD facilities with a rapid and cost-effective method for assessing potential human radiation exposures from the processing of chemical wastes contaminated with trace amounts of radionuclides.

  9. Life cycle assessment and additives: state of knowledge

    DEFF Research Database (Denmark)

    Concerns about possible toxic effects from additives/impurities accumulated in globally recycled waste/resources like paper and plastics was one of the main reasons for starting up the EU FP7 Coordination Action project RiskCycle (www.wadef.com/projects/riskcycle). A key aim of the project...... is to identify research needs within this area focusing on both risk assessment (RA) and life cycle assessment (LCA). Besides the sectors on paper and plastics also lubricants, textiles, electronics and leather are included in RiskCycle. On plastics a literature review regarding the state of knowledge...... on additives/impurities in LCA has been performed within RiskCycle. Several inventory databases (LCI data) have been investigated and the result shows that most LCI databases use PlasticsEurope data for plastics production. Most of these data are aggregated and do not include additives. Regarding...

  10. Identification and dose assessment of irradiated cardamom and cloves by EPR spectrometry

    Science.gov (United States)

    Beshir, W. B.

    2014-03-01

    The use of electron paramagnetic resonance spectroscopy to accurately distinguish irradiated from unirradiated cardamom and cloves and assesses the absorbed dose to radiation processed cardamom and cloves are examined. The results were successful for identifying both irradiated and unirradiated cardamom and cloves. Additive reirradiation of cardamom and cloves produces reproducible dose-response functions, which can be used to assess the initial dose by back-extrapolation. Third degree polynomial function was used to fit the EPR signal/dose curves. It was found that this 3rd degree polynomial function provides satisfactory results without correction of decay for free radicals. The stability of the radiation induced EPR signal of irradiated cardamom and cloves were studied over a storage period of almost 8 months.

  11. The additional value of first pass myocardial perfusion imaging during peak dose of dobutamine stress cardiac MRI for the detection of myocardial ischemia

    NARCIS (Netherlands)

    Lubbers, Daniel D.; Janssen, Caroline H. C.; Kuijpers, Dirkjan; Van Dijkman, Paul R. M.; Overbosch, Jelle; Willems, Tineke P.; Oudkerk, Matthijs

    2008-01-01

    Purpose of this study was to assess the additional value of first pass myocardial perfusion imaging during peak dose of dobutamine stress Cardiac-MR (CMR). Dobutamine Stress CMR was performed in 115 patients with an inconclusive diagnosis of myocardial ischemia on a 1.5 T system (Magnetom Avanto, Si

  12. Improvement of the following accident dose assessment system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Enn Han; Han, Moon Hee; Suh, Kyung Suk; Hwang, Won Tae; Choi, Young Gil [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1999-12-15

    The FADAS has been updates for calculating the real-time wind fields continuously at the nuclear sites in Korea. The system has been constructed to compute the wind fields using its own process for the dummy meteorological data, and dose not effect on the overall wind field module. If the radioactive materials are released into the atmosphere in real situation, the calculations of wind fields and exposure dose in the previous FADAS are performed in the case of the recognition of the above situation in the source term evaluation module. The current version of FADAS includes the program for evaluating the effect of the predicted accident and the assumed scenario together. The dose assessment module is separated into the real-time and the supposed accident respectively.

  13. ASSESSMENT OF COLLECTIVE DOSE FOR TRAVELLERS BY WATERS

    Institute of Scientific and Technical Information of China (English)

    岳清宇; 姜萍; 等

    1995-01-01

    People travelling by air will receive more exposure dose and by water will receive less one.According to statistic data from the Ministry of Communications in 1988,the turnover in that year was about 2×1010 man.km.The total number of fishermen for inshore fishing was nearly two million reported by Ministry of Agriculture,Animal Husbandry and Fishery.Based on measured data on 212 points in six typical shipping lines of inshore lines and inland rivers,and the total voyage is 5625km,the average natural radiation dose rate received by travellers was calculated.From that assessment of collective effective dose for passengers by water and fishermen was derived.The value is 32.7man.Sv for passengers and 265.3man.Sv for fishermen.

  14. Enhancement of neutron radiation dose by the addition of sulphur-33 atoms

    Energy Technology Data Exchange (ETDEWEB)

    Porras, I [Departamento de Fisica Atomica, Molecular y Nuclear (formerly Fisica Moderna), Facultad de Ciencias, Universidad de Granada, E-18071 Granada (Spain)], E-mail: porras@ugr.es

    2008-04-07

    The use of neutrons in radiotherapy allows the possibility of producing nuclear reactions in a specific target inserted in the medium. {sup 10}B is being used to induce reactions (n, {alpha}), a technique called boron neutron capture therapy. I have studied the possibility of inducing a similar reaction using the nucleus of {sup 33}S, for which the reaction cross section presents resonances for keV neutrons, the highest peak occurring at 13.5 keV. Here shown, by means of Monte Carlo simulation of point-like sources of neutrons in this energy range, is an enhancement effect on the absorbed dose in water by the addition of {sup 33}S atoms. In addition to this, as the range of the alpha particle is of the order of a mammalian cell size, the energy deposition via this reaction results mainly inside the cells adjacent to the interaction site. The main conclusion of the present work is that the insertion of these sulphur atoms in tumoral cells would enhance the effect of neutron irradiation in the keV range. (letter to the editor)

  15. Methods of assessing total doses integrated across pathways

    Energy Technology Data Exchange (ETDEWEB)

    Grzechnik, M.; Camplin, W.; Clyne, F. [Centre for Environment, Fisheries and Aquaculture Science, Lowestoft (United Kingdom); Allott, R. [Environment Agency, London (United Kingdom); Webbe-Wood, D. [Food Standards Agency, London (United Kingdom)

    2006-07-01

    Calculated doses for comparison with limits resulting from discharges into the environment should be summed across all relevant pathways and food groups to ensure adequate protection. Current methodology for assessments used in the radioactivity in Food and the Environment (R.I.F.E.) reports separate doses from pathways related to liquid discharges of radioactivity to the environment from those due to gaseous releases. Surveys of local inhabitant food consumption and occupancy rates are conducted in the vicinity of nuclear sites. Information has been recorded in an integrated way, such that the data for eachividual is recorded for all pathways of interest. These can include consumption of foods, such as fish, crustaceans, molluscs, fruit and vegetables, milk and meats. Occupancy times over beach sediments and time spent in close proximity to the site is also recorded for inclusion of external and inhalation radiation dose pathways. The integrated habits survey data may be combined with monitored environmental radionuclide concentrations to calculate total dose. The criteria for successful adoption of a method for this calculation were: Reproducibility can others easily use the approach and reassess doses? Rigour and realism how good is the match with reality?Transparency a measure of the ease with which others can understand how the calculations are performed and what they mean. Homogeneity is the group receiving the dose relatively homogeneous with respect to age, diet and those aspects that affect the dose received? Five methods of total dose calculation were compared and ranked according to their suitability. Each method was labelled (A to E) and given a short, relevant name for identification. The methods are described below; A) Individual doses to individuals are calculated and critical group selection is dependent on dose received. B) Individual Plus As in A, but consumption and occupancy rates for high dose is used to derive rates for application in future

  16. Dose assessment according to changes in algorithm in cardiac CT

    Science.gov (United States)

    Jang, H. C.; Cho, J. H.; Lee, H. K.; Hong, I. S.; Cho, M. S.; Park, C. S.; Lee, S. Y.; Dong, K. R.; Goo, E. H.; Chung, W. K.; Ryu, Y. H.; Lim, C. S.

    2012-06-01

    The principal objective of this study was to determine the effects of the application of the adaptive statistical iterative reconstruction (ASIR) technique in combination with another two factors (body mass index (BMI) and tube potential) on radiation dose in cardiac computed tomography (CT). For quantitative analysis, regions of interest were positioned on the central region of the great coronary artery, the right coronary artery, and the left anterior descending artery, after which the means and standard deviations of measured CT numbers were obtained. For qualitative analysis, images taken from the major coronary arteries (right coronary, left anterior descending, and left circumflex) were graded on a scale of 1-5, with 5 indicating the best image quality. Effective dose, which was calculated by multiplying the value of the dose length product by a standard conversion factor of 0.017 for the chest, was employed as a measure of radiation exposure dose. In cardiac CT in patients with BMI of less than 25 kg/m2, the use of 40% ASIR in combination with a low tube potential of 100 kVp resulted in a significant reduction in the radiation dose without compromising diagnostic quality. Additionally, the combination of the 120 kVp protocol and the application of 40% ASIR application for patients with BMI higher than 25 kg/m2 yielded similar results.

  17. Venous thromboembolism: Additional diagnostic value and radiation dose of pelvic CT venography in patients with suspected pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, Miriam, E-mail: Miriam.Reichert@umm.de [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Henzler, Thomas; Krissak, Radko; Apfaltrer, Paul [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Huck, Kurt [1st Department of Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim (Germany); Buesing, Karen [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Sueselbeck, Tim [1st Department of Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim (Germany); Schoenberg, Stefan O.; Fink, Christian [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany)

    2011-10-15

    Purpose: To assess the additional diagnostic value of indirect CT venography (CTV) of the pelvis and upper thighs performed after pulmonary CT angiography (CTA) for the diagnosis of venous thromboembolism (VTE). Materials and methods: In a retrospective analysis, the radiology information system entries between January 2003 and December 2007 were searched for patients who received pulmonary CTA and additional CTV of the pelvis and upper thighs. Of those patients, the radiology reports were reviewed for the diagnosis of pulmonary embolism (PE) and deep venous thrombosis (DVT) in the pelvic veins and veins of the upper thighs. In cases with an isolated pelvic thrombosis at CTV (i.e. which only had a thrombosis in the pelvic veins but not in the veins of the upper thigh) ultrasound reports were reviewed for the presence of DVT of the legs. The estimated radiation dose was calculated for pulmonary CTA and for CTV of the pelvis. Results: In the defined period 3670 patients were referred to our institution for exclusion of PE. Of those, 642 patients (353 men, 289 women; mean age, 65 {+-} 15 years, age range 18-98 years) underwent combined pulmonary CTA and CTV. Among them, PE was found in 227 patients (35.4%). In patients without PE CTV was negative in all cases. In patients with PE, CTV demonstrated pelvic thrombosis in 24 patients (3.7%) and thrombosis of the upper thighs in 43 patients (6.6%). Of those patients 14 (2.1%) had DVT in the pelvis and upper thighs. In 10 patients (1.5%) CTV showed an isolated pelvic thrombosis. Of those patients ultrasound reports were available in 7 patients, which revealed DVT of the leg veins in 5 cases (1%). Thus, the estimated prevalence of isolated pelvic thrombosis detected only by pelvic CTV ranges between 1-5/642 patients (0.1-0.7%). Radiation dose ranges between 4.8 and 9.7 mSv for additional CTV of the pelvis. Conclusion: CTV of the pelvis performed after pulmonary CTA is of neglectable additional diagnostic value for the

  18. Addition of phenylephrine to high-dose insulin in dihydropyridine overdose does not improve outcome.

    Science.gov (United States)

    Engebretsen, Kristin M; Morgan, Matthew W; Stellpflug, Samuel J; Cole, Jon B; Anderson, Christopher P; Holger, Joel S

    2010-10-01

    Vasopressors are commonly used for calcium channel blocker (CCB)-induced cardiogenic shock after calcium and high-dose insulin (HDI). Vasopressor therapy is frequently used in combination with HDI to increase blood pressure and improve outcome. However, no studies have compared the efficacy of HDI to the combination of a vasopressor and HDI in dihydropyridine overdose. We conducted a study to compare the efficacy of HDI to phenylephrine (PE) plus HDI in a porcine model of dihydropyridine toxicity. Cardiogenic shock was induced by administering a nifedipine (NP) infusion of 0.0125 mcg/kg/min until a point of toxicity, defined as a 25% decrease in the baseline product of mean arterial pressure (MAP) × cardiac output (CO). Each arm was resuscitated with 20 mL/kg of saline (NS). The nifedipine infusion continued throughout a 4-h resuscitation protocol. The HDI group was titrated up to 10 units/kg/h of insulin and the HDI/PE group was titrated up to a dose of HDI 10 units/kg/h plus PE 3.6 mcg/kg/min. No baseline differences were found among groups including time to toxicity. Survival was not different between the HDI and HDI/PE arms. When comparing the HDI to the HDI/PE arm no differences were found for cardiac index (CI) (p = 0.06), systemic vascular resistance (p = 0.34), heart rate (HR) (p = 0.95), mean arterial pressure (p = 0.99), pulmonary vascular resistance (PVR) (p = 0.07), or base excess (p = 0.36). In this model of nifedipine-induced cardiogenic shock, the addition of PE to HDI therapy did not improve mortality, cardiac output, blood pressure, systemic vascular resistance (SVR), or base excess.

  19. Assessment of patient dose in medical processes by in-vivo dose measuring devices: A review

    Science.gov (United States)

    Tuncel, Nina

    2016-11-01

    In-vivo dosimetry (IVD) in medicine especially in radiation therapy is a well-established and recommended procedure for the estimation of the dose delivered to a patient during the radiation treatment. It became even more important with the emerging use of new and more complex radiotherapy techniques such as intensity-modulated or image-guided radiation therapy. While IVD has been used in brachytherapy for decades and the initial motivation for performing was mainly to assess doses to organs at risk by direct measurements, it is now possible to calculate 3D for detection of deviations or errors. In-vivo dosimeters can be divided into real-time and passive detectors that need some finite time following irradiation for their analysis. They require a calibration against a calibrated ionization chamber in a known radiation field. Most of these detectors have a response that is energy and/or dose rate dependent and consequently require adjustments of the response to account for changes in the actual radiation conditions compared to the calibration situation. Correction factors are therefore necessary to take. Today, the most common dosimeters for patients' dose verification through in-vivo measurements are semiconductor diodes, thermo-luminescent dosimeters, optically stimulated luminescence dosimeters, metal-oxide-semiconductor field-effect transistors and plastic scintillator detectors with small outer diameters.

  20. Radiological environmental dose assessment methods and compliance dose results for 2015 operations at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Jannik, G. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, K. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-09-01

    This report presents the environmental dose assessment methods and the estimated potential doses to the offsite public from 2015 Savannah River Site (SRS) atmospheric and liquid radioactive releases. Also documented are potential doses from special-case exposure scenarios - such as the consumption of deer meat, fish, and goat milk.

  1. Radiological environmental dose assessment methods and compliance dose results for 2015 operations at the savannah river site

    Energy Technology Data Exchange (ETDEWEB)

    Jannik, G. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, K. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-09-01

    This report presents the environmental dose assessment methods and the estimated potential doses to the offsite public from 2015 Savannah River Site (SRS) atmospheric and liquid radioactive releases. Also documented are potential doses from special-case exposure scenarios - such as the consumption of deer meat, fish, and goat milk.

  2. Cone beam computed tomography radiation dose and image quality assessments.

    Science.gov (United States)

    Lofthag-Hansen, Sara

    2010-01-01

    Diagnostic radiology has undergone profound changes in the last 30 years. New technologies are available to the dental field, cone beam computed tomography (CBCT) as one of the most important. CBCT is a catch-all term for a technology comprising a variety of machines differing in many respects: patient positioning, volume size (FOV), radiation quality, image capturing and reconstruction, image resolution and radiation dose. When new technology is introduced one must make sure that diagnostic accuracy is better or at least as good as the one it can be expected to replace. The CBCT brand tested was two versions of Accuitomo (Morita, Japan): 3D Accuitomo with an image intensifier as detector, FOV 3 cm x 4 cm and 3D Accuitomo FPD with a flat panel detector, FOVs 4 cm x 4 cm and 6 cm x 6 cm. The 3D Accuitomo was compared with intra-oral radiography for endodontic diagnosis in 35 patients with 46 teeth analyzed, of which 41 were endodontically treated. Three observers assessed the images by consensus. The result showed that CBCT imaging was superior with a higher number of teeth diagnosed with periapical lesions (42 vs 32 teeth). When evaluating 3D Accuitomo examinations in the posterior mandible in 30 patients, visibility of marginal bone crest and mandibular canal, important anatomic structures for implant planning, was high with good observer agreement among seven observers. Radiographic techniques have to be evaluated concerning radiation dose, which requires well-defined and easy-to-use methods. Two methods: CT dose index (CTDI), prevailing method for CT units, and dose-area product (DAP) were evaluated for calculating effective dose (E) for both units. An asymmetric dose distribution was revealed when a clinical situation was simulated. Hence, the CTDI method was not applicable for these units with small FOVs. Based on DAP values from 90 patient examinations effective dose was estimated for three diagnostic tasks: implant planning in posterior mandible and

  3. An assessment of bias and uncertainty in recorded dose from external sources of radiation for workers at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Fix, J.J.; Gilbert, E.S.; Baumgartner, W.V.

    1994-08-01

    Worker dose estimates are used in epidemiologic studies of nuclear workers. A major objective of these studies is to provide a direct assessment of the carcinogenic risk of exposure to ionizing radiation at low doses and dose rates. If dose estimates used in analyses of worker data are biased, then risk estimates expressed per unit of dose will also be biased. In addition, random error in dose estimates may lead to underestimation of risk coefficients and can also distort dose-response analyses. Analyses of data from nuclear worker studies, including Hanford, have typically not been adjusted for biases and uncertainties in dose estimates in part because of the lack of adequate information on the nature and magnitude of these biases and uncertainties. This report describes an approach used to assess bias and uncertainty in radiation dose for Hanford dosimetry systems. The approach can be considered as an elaboration of work conducted by a technical committee appointed by the National Academy of Sciences (NAS) used to quantify the bias and uncertainty in estimated doses for personnel exposed to radiation as a result of atmospheric testing of nuclear weapons between 1945 and 1962. In addition, laboratory studies were conducted to measure bias for selected sources of photon radiation resulting from angular response characteristics of Hanford dosimeter systems. An overall assessment is presented of bias and uncertainty for photon radiation greater than 100 keV. This radiation is expected to have caused the vast majority of recorded dose for Hanford workers.

  4. Dose assessment associated with granite use in residential property

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Andre Luiz do Carmo, E-mail: andre.leal@ifrj.edu.br [Instituto Federal do Rio de Janeiro (IFRJ), Sao Goncalo, RJ (Brazil); Lauria, Dejanira da Costa, E-mail: dejanira@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The radioactivity levels in materials used as building materials have been reported in many countries and relatively high levels of radioactivity have been identified in some materials build (Beretka and Mathew, 1985; Pavlidou et al., 2006; Tzortzis et al., 2003 ; Al-Selah and Al-Berzan, 2007; Kitto et al.,2009 ; Myatt et al., 2010 ). Although is reported in the literature some studies on the levels of radionuclides in granites and the associated doses (Salas, 2003; Ahmed et al., 2006; Bonotto et al, 2009 ; Turhan, 2012; Anjos et al., 2005, 2012), most of assessed dose are related with external exposure data (Anjos et al., 2011, Llope, 2011 ). From the radionuclide concentrations in 10 samples of granite rock, this study evaluated the dose by inhalation of radon from the use of national granites as floor covering, according to the refresh rate of air, porosity, and radon emanation rate of diffusion coefficient by sensitivity analyzes, using the RESRAD-BUILD 3.5 code. As a result, it was found that the higher dose by radon inhalation was 0.058 mSv / year and the Rn-220 isotope is the largest contributor to this route of exposure. (author)

  5. A A field test for extremity dose assessment during outages at Korean nuclear power plants.

    Science.gov (United States)

    Kim, Hee Geun; Kong, Tae Young

    2013-05-01

    During maintenance on the water chamber of a steam generator, the pressuriser heater and the pressure tube feeder in nuclear power plants, workers are likely to receive high radiation doses due to the severe workplace conditions. In particular, it is expected that workers' hands would receive the highest radiation doses because of their contact with the radioactive materials. In this study, field tests for extremity dose assessments in radiation workers undertaking contact tasks with high radiation doses were conducted during outages at pressurised water reactors and pressurised heavy water reactors in Korea. In the test, the radiation workers were required to wear additional thermoluminescent dosemeters (TLDs) on their backs and wrists and an extremity dosemeter on the finger, as well as a main TLD on the chest while performing the maintenance tasks.

  6. Characteristics of the graded wildlife dose assessment code K-BIOTA and its application

    Energy Technology Data Exchange (ETDEWEB)

    Keum, Dong Kwon; Jun, In; Lim, Kwang Muk; Kim, Byeong Ho; Choi, Yong Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-12-15

    This paper describes the technical background for the Korean wildlife radiation dose assessment code, K-BIOTA, and the summary of its application. The K-BIOTA applies the graded approaches of 3 levels including the screening assessment (Level 1 and 2), and the detailed assessment based on the site specific data (Level 3). The screening level assessment is a preliminary step to determine whether the detailed assessment is needed, and calculates the dose rate for the grouped organisms, rather than an individual biota. In the Level 1 assessment, the risk quotient (RQ) is calculated by comparing the actual media concentration with the environmental media concentration limit (EMCL) derived from a bench-mark screening reference dose rate. If RQ for the Level 1 assessment is less than 1, it can be determined that the ecosystem would maintain its integrity, and the assessment is terminated. If the RQ is greater than 1, the Level 2 assessment, which calculates RQ using the average value of the concentration ratio (CR) and equilibrium distribution coefficient (Kd) for the grouped organisms, is carried out for the more realistic assessment. Thus, the Level 2 assessment is less conservative than the Level 1 assessment. If RQ for the Level 2 assessment is less than 1, it can be determined that the ecosystem would maintain its integrity, and the assessment is terminated. If the RQ is greater than 1, the Level 3 assessment is performed for the detailed assessment. In the Level 3 assessment, the radiation dose for the representative organism of a site is calculated by using the site specific data of occupancy factor, CR and Kd. In addition, the K-BIOTA allows the uncertainty analysis of the dose rate on CR, Kd and environmental medium concentration among input parameters optionally in the Level 3 assessment. The four probability density functions of normal, lognormal, uniform and exponential distribution can be applied. The applicability of the code was tested through the

  7. Improvement of the following accident dose assessment system (II)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Enn Han; Han, Moon Hee; Suh, Kyung Suk; Hwang, Won Tae; Choi, Young Gil [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-12-01

    The FADAS and its database have been updates for calculating the real-time wind fields continuously at the nuclear sites in Korea. The system has been constructed to compute the wind fields using its own process for the dummy meteorological data, and does not effect on the overall wind field module. If the radioactive materials are released into the atmosphere in real situation, the calculations of wind fields and exposure dose in the previous FADAS are performed in the case of the recognition of the above situation in the source term evaluation module. The current version of FADAS includes the program for evaluating the effect of the predicted accident and the assumed scenario together. The dose assessment module is separated into the real-time and the supposed accident respectively. 7 refs., 8 figs., 6 tabs. (Author)

  8. Smartphone apps for calculating insulin dose: a systematic assessment.

    Science.gov (United States)

    Huckvale, Kit; Adomaviciute, Samanta; Prieto, José Tomás; Leow, Melvin Khee-Shing; Car, Josip

    2015-05-06

    Medical apps are widely available, increasingly used by patients and clinicians, and are being actively promoted for use in routine care. However, there is little systematic evidence exploring possible risks associated with apps intended for patient use. Because self-medication errors are a recognized source of avoidable harm, apps that affect medication use, such as dose calculators, deserve particular scrutiny. We explored the accuracy and clinical suitability of apps for calculating medication doses, focusing on insulin calculators for patients with diabetes as a representative use for a prevalent long-term condition. We performed a systematic assessment of all English-language rapid/short-acting insulin dose calculators available for iOS and Android. Searches identified 46 calculators that performed simple mathematical operations using planned carbohydrate intake and measured blood glucose. While 59% (n = 27/46) of apps included a clinical disclaimer, only 30% (n = 14/46) documented the calculation formula. 91% (n = 42/46) lacked numeric input validation, 59% (n = 27/46) allowed calculation when one or more values were missing, 48% (n = 22/46) used ambiguous terminology, 9% (n = 4/46) did not use adequate numeric precision and 4% (n = 2/46) did not store parameters faithfully. 67% (n = 31/46) of apps carried a risk of inappropriate output dose recommendation that either violated basic clinical assumptions (48%, n = 22/46) or did not match a stated formula (14%, n = 3/21) or correctly update in response to changing user inputs (37%, n = 17/46). Only one app, for iOS, was issue-free according to our criteria. No significant differences were observed in issue prevalence by payment model or platform. The majority of insulin dose calculator apps provide no protection against, and may actively contribute to, incorrect or inappropriate dose recommendations that put current users at risk of both catastrophic overdose and more

  9. High-dose aspirin in addition to daily low-dose aspirin decreases platelet activation in patients before and after percutaneous coronary intervention.

    NARCIS (Netherlands)

    Berg, J.M. ten; Gerritsen, W.B.M.; Haas, F.J.L.M.; Kelder, J.C.; Verheugt, F.W.A.; Plokker, H.W.M.

    2002-01-01

    BACKGROUND: Activated platelets play a major role in acute vessel closure after coronary angioplasty. Although aspirin is the routine therapy during angioplasty, it only incompletely prevents acute closure. This might be due to suboptimal dosing. OBJECTIVE: First, to study the effect of additional

  10. Landscape dose conversion factors used in the safety assessment SR-Site

    Energy Technology Data Exchange (ETDEWEB)

    Avila, Rodolfo; Ekstroem, Per-Anders; Aastrand, Per-Gustav (Facilia AB (Sweden))

    2010-12-15

    In this report two types of Dose Conversion Factors have been derived: i) a Landscape Dose Conversion Factor (LDF) that is applicable to continuous long-term releases to the biosphere at a constant rate, and ii) a Landscape Dose Conversion Factor for pulse releases (LDF pulse) that is applicable to a radionuclide release that reaches the biosphere in a pulse within years to hundreds of years. In SR-Site these Dose Factors are multiplied with modelled release rates or pulse releases from the geosphere to obtain dose estimates used in assessment of compliance with the regulatory risk criterion. The LDFs were calculated for three different periods of the reference glacial cycle; a period of submerged conditions following the deglaciation, the temperate period, and a prolonged period of periglacial conditions. Additionally, LDFs were calculated for the global warming climate case. The LDF pulse was calculated only for temperate climate conditions. The LDF and LDF pulse can be considered as Best Estimate values, which can be used in calculations of Best Estimate values of doses to a representative individual of the most exposed group from potential releases from a future repository. A systematic analysis of the effects of system, model and parameter uncertainties on the LDFs has been carried out. This analysis has shown that the use of the derived LDF would lead to cautious or realistic dose estimates. The models and methods that were used for derivation of the LDFs and LDF pulse are also described in this report

  11. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico

    Science.gov (United States)

    Luevano-Gurrola, Sergio; Perez-Tapia, Angelica; Pinedo-Alvarez, Carmelo; Carrillo-Flores, Jorge; Montero-Cabrera, Maria Elena; Renteria-Villalobos, Marusia

    2015-01-01

    Determining ionizing radiation in a geographic area serves to assess its effects on a population’s health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h−1. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226Ra, 232Th and 40K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h−1. Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg−1, for 226Ra, 232Th and 40K, respectively. From the analysis, the spatial distribution of 232Th, 226Ra and 40K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize. PMID:26437425

  12. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico.

    Science.gov (United States)

    Luevano-Gurrola, Sergio; Perez-Tapia, Angelica; Pinedo-Alvarez, Carmelo; Carrillo-Flores, Jorge; Montero-Cabrera, Maria Elena; Renteria-Villalobos, Marusia

    2015-09-30

    Determining ionizing radiation in a geographic area serves to assess its effects on a population's health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h(-1). At the same sites, 48 soil samples were taken to obtain the activity concentrations of (226)Ra, (232)Th and (40)K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h(-1). Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg(-1), for (226)Ra, (232)Th and (40)K, respectively. From the analysis, the spatial distribution of (232)Th, (226)Ra and (40)K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

  13. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico

    Directory of Open Access Journals (Sweden)

    Sergio Luevano-Gurrola

    2015-09-01

    Full Text Available Determining ionizing radiation in a geographic area serves to assess its effects on a population’s health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h−1. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226Ra, 232Th and 40K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h−1. Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg−1, for 226Ra, 232Th and 40K, respectively. From the analysis, the spatial distribution of 232Th, 226Ra and 40K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

  14. Assessing medical students’ competence in calculating drug doses

    Directory of Open Access Journals (Sweden)

    Catherine Harries

    2013-09-01

    Full Text Available Evidence suggests that healthcare professionals are not optimally able to calculate medicine doses and various strategies have been employed to improve these skills. In this study, the performance of third and fourth year medical students was assessed and the success of various educational interventions investigated. Students were given four types of dosing calculations typical of those required in an emergency setting. Full competence (at the 100% level was defined as correctly answering all four categories of calculation at any one time. Three categories correct meant competence at the 75% level. Interventions comprised an assignment with a model answer for self-assessment in the third year and a small group tutorial in the fourth year. The small groups provided opportunities for peer-assisted learning. A subgroup of 23 students received individual tuition from the lecturer prior to the start of the fourth year. Amongst the 364 eligible students, full competence rose from 23% at the beginning of the third year to 66% by the end of the fourth year. More students succeeded during the fourth than the third year of study. Success of small group tuition was assessed in a sample of 200 students who had formal assessments both before and after the fourth year tuition. Competence at the 75% level improved by 10% in attendees and decreased by 3% in non-attendees, providing evidence of the value of students receiving assistance from more able same-language peers. Good results were achieved with one-on-one tuition where individualised assistance allowed even struggling students to improve.

  15. Intermediate dose cidofovir does not cause additive nephrotoxicity in BK virus allograft nephropathy.

    Science.gov (United States)

    Araya, Carlos E; Lew, Judy F; Fennell, Robert S; Neiberger, Richard E; Dharnidharka, Vikas R

    2008-11-01

    BKVAN has emerged as a major morbidity in kidney transplant recipients. Among treatment options is cidofovir, which can be nephrotoxic. We previously reported that intermediate dose cidofovir could be used without significant nephrotoxicity. We present extended results of the same treatment protocol in a larger cohort and with longer follow up. Diagnosis of BKVAN was based on detection of BK viral DNA from plasma and renal allograft biopsy tissue. All patients received cidofovir (0.25-1 mg/kg/dose) every 2-3 wk. Total number of cidofovir doses ranged from 1 to 18 (mean 8). This report includes eight patients, aged 5-21 yr, treated with intermediate dose cidofovir. Median follow-up was 11 months (range 4-32). Mean fall in reciprocal of serum creatinine (1/sCr) from baseline at BKVAN diagnosis was 64% (range 28-120%). A time-series plot of plasma BK virus PCR and 1/sCr showed marked reduction in viral loads without significant deterioration in 1/sCr from the initial value at BKVAN diagnosis. In this larger series with extended follow up, intermediate dose cidofovir without probenecid for the treatment of BKVAN continues to show stabilization of renal function without progression to renal failure.

  16. Axillary block duration and related hemodynamic changes: high versus low dose Adrenaline addition to Lidocaine

    Directory of Open Access Journals (Sweden)

    Shariat Moharari R

    2009-03-01

    Full Text Available "nBackground: Axillary block is used for inducing anesthesia in outpatient hand and forearm surgeries. Few researches have studied hemodynamic and blockade effects of low doses of Epinephrine. The aim of the present study was to compare the duration of analgesia and hemodynamic changes following the injection of high/low epinephrine doses in such surgeries. "nMethods: The present randomized clinical trial study was conducted on healthy individuals (ASA I-II who were candidates for hand and forearm surgeries. The patients were randomly divided into three groups. The first two groups were allocated to receive lidocaine with low (0.6µg/cc and high (5µg/cc doses of epinephrine whereas lidocaine plus normal saline was injected in the third group. The hemodynamic changes (Mean arterial blood pressure and heart rate and the occurance of any side-effects along with the duration of analgesia and motor block were recorded. "nResults: From among the total of 75 patients, 15 cases were excluded due to incomplete blockade or failure needing general anesthesia. The duration of analgesia and the motor block were longer in the high dose epinephrine group, the difference, however, was not statistically significant. Heart rate changes within the groups was significant in the 4th-7th and 10th minutes. Mean arterial blood pressure changes was only significant in the 4th minute, within the groups. "nConclusions: Administering low doses of epinephrine plus lidocaine as a local anesthetic not only provides acceptable analgesia compared to higher doses of the medication, but also is associated with fewer side effects.

  17. Simple DVH parameter addition as compared to deformable registration for bladder dose accumulation in cervix cancer brachytherapy

    DEFF Research Database (Denmark)

    Andersen, Else Stougård; Noe, Karsten Østergaaard; Sørensen, Thomas Sangild

    2013-01-01

    called "the worst case assumption") in fractionated BT. Materials and methods: Forty-seven patients treated for locally advanced cervical cancer were included. All patients received EBRT combined with two individually planned 3D image-guided adaptive BT fractions. D2 and D0.1 were estimated by DVH...... parameter addition and compared to dose accumulations based on an in-house developed biomechanical deformable image registration (DIR) algorithm. Results: DIR-based DVH analysis was possible in 42/47 patients. DVH parameter addition resulted in mean dose deviations relative to DIR of 0.4 ± 0.3 Gy (1.5 ± 1...

  18. Committed dose assessment based on background outdoor gamma exposure in Chihuahua City, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Luevano G, S.; Perez T, A.; Pinedo A, C.; Renteria V, M. [Universidad Autonoma de Chihuahua, Facultad de Zootecnia y Ecologia, Perif. Francisco R. Almada Km 1, 31415 Chihuahua, Chih. (Mexico); Carrillo F, J.; Montero C, M. E., E-mail: mrenteria@uach.mx [Centro de Investigacion en Materiales Avanzados, Miguel de Cervantes 120, 31136 Chihuahua, Chih. (Mexico)

    2015-10-15

    Full text: Determining ionizing radiation in a geographic area serves to assess its effects on populations health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the committed dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, annual effective dose, and the lifetime cancer risk, 48 sampling points were randomly selected along the Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Muller counter. At the same sites, 48 soil samples were taken to obtain the activity concentrations of {sup 226}Ra, {sup 232}Th, {sup 40}K and their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Outdoor gamma dose rates ranged from 56 to 193 n Gy h{sup -1}. Results indicated that lifetime effective dose to inhabitants of Chihuahua City is in average of 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of activity concentrations in soil were 51.8, 73.1, and 1096.5 Bq kg{sup -1}, of {sup 226}Ra, {sup 232}Th and {sup 40}K, respectively. From the analysis of the spatial distribution of {sup 232}Th, {sup 226}Ra, and {sup 40}K is to north, to north-center, and to south of city, respectively. In conclusion, natural background gamma dose received by inhabitants of Chihuahua City is high and mainly due to geological characteristics of the zone. (Author)

  19. Dose reconstruction starting from the pre-dose effect of quartz: combined procedure of additive dose and multiple activation; Reconstruccion de dosis a partir del efecto pre-dosis del cuarzo: procedimiento combinado de dosis aditiva y activacion multiple

    Energy Technology Data Exchange (ETDEWEB)

    Correcher, V.; Gomez R, J. M.; Delgado, A. [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, Av. Complutense 22, 28040 Madrid (Spain); Garcia G, J. [Consejo Superior de Investigaciones Cientificas, Museo Nacional de Ciencias Naturales, Jose Gutierrez Abascal No. 2, 28006 Madrid (Spain)], e-mail: v.correcher@ciemat.es

    2009-07-01

    The pre-dose effect of the 110 C thermoluminescence (Tl) peak of quartz gives rise to the use of a sensitive technique to estimate of low-level doses under retrospective conditions. However, one can appreciate how aliquots of quartz, from the same mineral fraction, display different sensitivities. In this sense, we herein report on a new measurement protocol based on the aforementioned pre-dose effect. Such procedure includes additive dose and multiple activation steps allows to determine simultaneously the sensitivity changes induced by the thermal activation and the Tl dose dependence. This behaviour let calculate the field accrued dose by interpolation thus permitting an increase of both precision and accuracy. (Author)

  20. Addition of low dose hCG to rFSh benefits older women during ovarian stimulation for IVF

    Directory of Open Access Journals (Sweden)

    Gomaa Hala

    2012-08-01

    Full Text Available Abstract Background To compare the outcome of IVF cycles in women receiving controlled ovarian stimulation with recFSH or recFSH plus low dose hCG. Methods A retrospective case control study, performed at a private practice affiliated with an academic institute. Patients were infertile women who were treated with IVF/ICSI and controlled ovarian stimulation in a long GnRH agonist protocol using either low dose hCG in addition to recFSH [N = 88] or recFSH alone [N = 99]. Primary outcomes were mean FSH dose, number of mature eggs, number of fertilized eggs, and serum levels of estradiol. Secondary outcomes were endometrial thickness, cycle cancellations and pregnancy rates. Results A significant increase in number of mature and fertilized eggs was observed in women over 40 years of age using low dose hCG in addition to recFSH. The estradiol level was significantly higher on the day of hCG administration and the serum level of FSH on cycle day 7 and on the day of hCG administration were lower. Conclusion Addition of low dose hCG to recFSH compared with recFSH alone significantly modified cycle characteristics in patients >/= 40 years and could be of potential benefit for IVF cycles in older infertile women.

  1. Rectal and bladder dose reduction with the addition of intravaginal balloons to vaginal packing in intracavitary brachytherapy for cervical cancer.

    Science.gov (United States)

    Eng, T Y; Patel, A J; Ha, C S

    2016-01-01

    The use of intravaginal Foley balloons in addition to conventional packing during high-dose-rate (HDR) tandem and ovoids intracavitary brachytherapy (ICBT) is a means to improve displacement of organs at risk, thus reducing dose-dependent complications. The goal of this project was to determine the reduction in dose achieved to the bladder and rectum with intravaginal Foley balloons with CT-based planning and to share our packing technique. One hundred and six HDR-ICBT procedures performed for 38 patients were analyzed for this report. An uninflated Foley balloon was inserted into the vagina above and below the tandem flange separately and secured in place with vaginal packing. CT images were then obtained with both inflated and deflated Foley balloons. Plan optimization occurred and dose volume histogram data were generated for the bladder and rectum. Maximum dose to 0.1, 1.0, and 2.0 cm(3) volumes for the rectum and bladder were analyzed and compared between inflated and deflated balloons using parametric statistical analysis. Inflation of intravaginal balloons allowed significant reduction of dose to the bladder and rectum. Amount of reduction was dependent on the anatomy of the patient and the placement of the balloons. Displacement of the organs at risk by the balloons allowed an average of 7.2% reduction in dose to the bladder (D0.1 cm(3)) and 9.3% to the rectum (D0.1 cm(3)) with a maximum reduction of 41% and 43%, respectively. For patients undergoing HDR-ICBT, a significant dose reduction to the bladder and rectum could be achieved with further displacement of these structures using intravaginal Foley balloons in addition to conventional vaginal packing. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  2. Monitoring system for the quality assessment in additive manufacturing

    Science.gov (United States)

    Carl, Volker

    2015-03-01

    Additive Manufacturing (AM) refers to a process by which a set of digital data -representing a certain complex 3dim design - is used to grow the respective 3dim real structure equal to the corresponding design. For the powder-based EOS manufacturing process a variety of plastic and metal materials can be used. Thereby, AM is in many aspects a very powerful tool as it can help to overcome particular limitations in conventional manufacturing. AM enables more freedom of design, complex, hollow and/or lightweight structures as well as product individualisation and functional integration. As such it is a promising approach with respect to the future design and manufacturing of complex 3dim structures. On the other hand, it certainly calls for new methods and standards in view of quality assessment. In particular, when utilizing AM for the design of complex parts used in aviation and aerospace technologies, appropriate monitoring systems are mandatory. In this respect, recently, sustainable progress has been accomplished by joining the common efforts and concerns of a manufacturer Additive Manufacturing systems and respective materials (EOS), along with those of an operator of such systems (MTU Aero Engines) and experienced application engineers (Carl Metrology), using decent know how in the field of optical and infrared methods regarding non-destructive-examination (NDE). The newly developed technology is best described by a high-resolution layer by layer inspection technique, which allows for a 3D tomography-analysis of the complex part at any time during the manufacturing process. Thereby, inspection costs are kept rather low by using smart image-processing methods as well as CMOS sensors instead of infrared detectors. Moreover, results from conventional physical metallurgy may easily be correlated with the predictive results of the monitoring system which not only allows for improvements of the AM monitoring system, but finally leads to an optimisation of the quality

  3. Monitoring system for the quality assessment in additive manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Carl, Volker, E-mail: carl@t-zfp.de [Carl Messtechnik, Thyssenstrasse 183a, 46535 Dinslaken (Germany)

    2015-03-31

    Additive Manufacturing (AM) refers to a process by which a set of digital data -representing a certain complex 3dim design - is used to grow the respective 3dim real structure equal to the corresponding design. For the powder-based EOS manufacturing process a variety of plastic and metal materials can be used. Thereby, AM is in many aspects a very powerful tool as it can help to overcome particular limitations in conventional manufacturing. AM enables more freedom of design, complex, hollow and/or lightweight structures as well as product individualisation and functional integration. As such it is a promising approach with respect to the future design and manufacturing of complex 3dim structures. On the other hand, it certainly calls for new methods and standards in view of quality assessment. In particular, when utilizing AM for the design of complex parts used in aviation and aerospace technologies, appropriate monitoring systems are mandatory. In this respect, recently, sustainable progress has been accomplished by joining the common efforts and concerns of a manufacturer Additive Manufacturing systems and respective materials (EOS), along with those of an operator of such systems (MTU Aero Engines) and experienced application engineers (Carl Metrology), using decent know how in the field of optical and infrared methods regarding non-destructive-examination (NDE). The newly developed technology is best described by a high-resolution layer by layer inspection technique, which allows for a 3D tomography-analysis of the complex part at any time during the manufacturing process. Thereby, inspection costs are kept rather low by using smart image-processing methods as well as CMOS sensors instead of infrared detectors. Moreover, results from conventional physical metallurgy may easily be correlated with the predictive results of the monitoring system which not only allows for improvements of the AM monitoring system, but finally leads to an optimisation of the quality

  4. Assessment of effective dose to staff in brachytherapy.

    Science.gov (United States)

    Faulkner, K; James, H V; Chapple, C L; Rawlings, D J

    1996-11-01

    The aim of this paper is to investigate the problem of monitoring effective dose to hospital staff who are involved in the treatment of tumors using sealed sources placed inside the body (brachytherapy). In addition, the use of an unsealed source to treat the thyroid was also considered. Radiation distributions produced by both sealed sources commonly used in brachytherapy (192I, 137Cs, 226Ra) and an unsealed source used in the treatment of the thyroid (131I) were used to irradiate a Rando phantom. The brachytherapy treatments of esophageal and gynecological carcinoma were simulated. The Rando phantom was loaded with lithium fluoride thermoluminescent dosimeters at positions corresponding to a number of radiosensitive organs. Film badges and electronic personal dosimeters were attached to the Rando phantom at various anatomical sites. The Rando phantom was positioned adjacent to the patient at an angle of 90 degrees to the longitudinal axis of the patient. Irradiations were performed with and without a portable lead screen used on the radiotherapy wards. Effective dose was estimated for each simulated radiotherapy treatment and compared with the personal monitor readings. The data were used as a basis for the provision of advice on the wearing of the film badge dosimeters and the design of portable lead screens. The data also permitted a comparison between the two types of dosimeter when used for personal monitoring in brachytherapy.

  5. The renal and neurohumoral effects of the addition of low-dose dopamine in septic critically ill patients

    NARCIS (Netherlands)

    Girbes, ARJ; Patten, MT; McCloskey, BV; Groeneveld, ABJ; Hoogenberg, K

    2000-01-01

    Objectives: Dopamine exerts a complicated action on the cardiovascular-renal and neurohumoral systems. We evaluated the effects of the addition of different doses of dopamine on top of treatment with norepinephrine on the haemodynamics, renal function and neurohormones of septic shock patients. Desi

  6. Low dose powdered activated carbon addition at high sludge retention times to reduce fouling in membrane bioreactors

    NARCIS (Netherlands)

    Remy, Maxime; Marel, van der Perry; Zwijnenburg, Arie; Rulkens, Wim; Temmink, Hardy

    2009-01-01

    The addition of a low concentration of PAC (0.5 g L−1 of sludge, i.e. a dose of 4 mg L−1 of wastewater), in combination with a relatively long SRT (50 days), to improve membrane filtration performance was investigated in two pilot-scale MBRs treating real municipal wastewater. Continuous filterabili

  7. Low dose powdered activated carbon addition at high sludge retention times to reduce fouling in membrane bioreactors

    NARCIS (Netherlands)

    Remy, M.J.J.; Marel, van der P.; Zwijnenburg, A.; Rulkens, W.H.; Temmink, B.G.

    2009-01-01

    The addition of a low concentration of PAC (0.5 g L-1 of sludge, i.e. a dose of 4 mg L-1 of wastewater), in combination with a relatively long SRT (50 days), to improve membrane filtration performance was investigated in two pilot-scale MBRs treating real municipal wastewater. Continuous filterabili

  8. Assessment of population external irradiation doses with consideration of Rospotrebnadzor bodies equipment for monitoring of photon radiation dose

    Directory of Open Access Journals (Sweden)

    I. P. Stamat

    2016-01-01

    Full Text Available This paper provides review of equipment and methodology for measurement of photon radiation dose; analysis of possible reasons for considerable deviation between the Russian Federation population annual effective external irradiation doses and the relevant average global value. Data on Rospotrebnadzor bodies dosimetry equipment used for measurement of gamma radiation dose are collected and systematized. Over 60 kinds of dosimeters are used for monitoring of population external irradiation doses. Most of dosimeters used in the country have gas-discharge detectors (Geiger-Mueller counters, minor biochemical annunciators, etc. which have higher total values of own background level and of space radiation response than the modern dosimeters with scintillation detectors. This feature of dosimeters is apparently one of most plausible reasons of a bit overstating assessment of population external irradiation doses. The options for specification of population external irradiation doses assessment are: correction of gamma radiation dose measurement results with consideration of dosimeters own background level and space radiation response, introduction of more up-to-date dosimeters with scintillation detectors, etc. The most promising direction of research in verification of population external irradiation doses assessment is account of dosimetry equipment.

  9. Diffuse and fugitive emission dose assessment on the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Davis, W.E.; Schmidt, J.W.; Gleckler, B.P. [Westinghouse Hanford Co., Richland, WA (United States); Rhoads, K. [Pacific Northwest Lab., Richland, WA (United States)

    1995-01-01

    On February 3, 1993, the US Department of Energy, Richland Operations Office (RL), received a Compliance Order and Information Request from the Director of the Air and Toxics Division of the US Environmental Protection Agency (EPA), Region 10. The Compliance Order requires RL to (1) evaluate all radionuclide emission points at the Hanford Site to determine which are subject to continuous emission measurement requirements in 40 Code of Federal Regulations (CFR) 61, Subpart H, and (2) continuously measure radionuclide emissions in accordance with 40 CFR 61.93. The Information Request requires RL to provide a written Compliance Plan to meet the requirements of the Compliance Order. The RL Compliance Plan included as one of its milestones the requirement to develop a Federal Facility Compliance Agreement (FFCA). An FFCA was negotiated between RL and the EPA, Region 10, and was entered into on February 7, 1994. One of the milestones was to provide EPA, Region 10, with a copy of the Federal Clean Air Act Title V operating air permit application and Air Emission Inventory (AEI) concurrent with its submission to the Washington State Department of Ecology. The AEI will include an assessment of the diffuse and fugitive emissions from the Hanford Site. This assessment does not identify any diffuse or fugitive emission source that would cause an effective dose equivalent greater than 0.1 mrem/yr.

  10. Technology Assessment and Roadmap for the Emergency Radiation Dose Assessment Program

    Energy Technology Data Exchange (ETDEWEB)

    Turteltaub, K W; Hartman-Siantar, C; Easterly, C; Blakely, W

    2005-10-03

    A Joint Interagency Working Group (JIWG) under the auspices of the Department of Homeland Security Office of Research and Development conducted a technology assessment of emergency radiological dose assessment capabilities as part of the overall need for rapid emergency medical response in the event of a radiological terrorist event in the United States. The goal of the evaluation is to identify gaps and recommend general research and development needs to better prepare the Country for mitigating the effects of such an event. Given the capabilities and roles for responding to a radiological event extend across many agencies, a consensus of gaps and suggested development plans was a major goal of this evaluation and road-mapping effort. The working group consisted of experts representing the Departments of Homeland Security, Health and Human Services (Centers for Disease Control and the National Institutes of Health), Food and Drug Administration, Department of Defense and the Department of Energy's National Laboratories (see appendix A for participants). The specific goals of this Technology Assessment and Roadmap were to: (1) Describe the general context for deployment of emergency radiation dose assessment tools following terrorist use of a radiological or nuclear device; (2) Assess current and emerging dose assessment technologies; and (3) Put forward a consensus high-level technology roadmap for interagency research and development in this area. This report provides a summary of the consensus of needs, gaps and recommendations for a research program in the area of radiation dosimetry for early response, followed by a summary of the technologies available and on the near-term horizon. We then present a roadmap for a research program to bring present and emerging near-term technologies to bear on the gaps in radiation dose assessment and triage. Finally we present detailed supporting discussion on the nature of the threats we considered, the status of

  11. Lack of benefit for the addition of androgen deprivation therapy to dose-escalated radiotherapy in the treatment of intermediate- and high-risk prostate cancer.

    LENUS (Irish Health Repository)

    Krauss, Daniel

    2012-02-01

    PURPOSE: Assessment of androgen deprivation therapy (ADT) benefits for prostate cancer treated with dose-escalated radiotherapy (RT). METHODS AND MATERIALS: From 1991 to 2004, 1,044 patients with intermediate- (n = 782) or high-risk (n = 262) prostate cancer were treated with dose-escalated RT at William Beaumont Hospital. Patients received external-beam RT (EBRT) alone, brachytherapy (high or low dose rate), or high dose rate brachytherapy plus pelvic EBRT. Intermediate-risk patients had Gleason score 7, prostate-specific antigen (PSA) 10.0-19.9 ng\\/mL, or Stage T2b-T2c. High-risk patients had Gleason score 8-10, PSA >\\/=20, or Stage T3. Patients were additionally divided specifically by Gleason score, presence of palpable disease, and PSA level to further define subgroups benefitting from ADT. RESULTS: Median follow-up was 5 years; 420 patients received ADT + dose-escalated RT, and 624 received dose-escalated RT alone. For all patients, no advantages in any clinical endpoints at 8 years were associated with ADT administration. No differences in any endpoints were associated with ADT administration based on intermediate- vs. high-risk group or RT modality when analyzed separately. Patients with palpable disease plus Gleason >\\/=8 demonstrated improved clinical failure rates and a trend toward improved survival with ADT. Intermediate-risk patients treated with brachytherapy alone had improved biochemical control when ADT was given. CONCLUSION: Benefits of ADT in the setting of dose-escalated RT remain poorly defined. This question must continue to be addressed in prospective study.

  12. Assessment of Gasoline Additive Containing Ditert-butoxypropanol

    Energy Technology Data Exchange (ETDEWEB)

    West, Brian H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Connatser, Raynella M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lewis, Samuel Arthur [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    The Fuels, Engines, and Emissions Research Center completed analysis and testing of the CPS Powershot gasoline additive under the auspices of the Department of Energy’s Technical Assistance for US Small Businesses in Vehicle Technologies. Gas chromatography-mass spectrometry (GC-MS) was used to quantify the makeup of the additive, finding a predominance of 2,3-Ditert-Butoxypropanol, also known as Glyceryl Di-Tert-Butyl Ether (GTBE). Blends of the additive at 2 and 4 volume percent were subjected to a number of standard ASTM tests, including Research Octane Number, Motor Octane Number, distillation, and vapor pressure. Results show a high boiling range and low vapor pressure for the additive, and a very modest octane boosting effect in gasoline with and without ethanol.

  13. Evaluation of various approaches for assessing dose indicators and patient organ doses resulting from radiotherapy cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Rampado, Osvaldo, E-mail: orampado@cittadellasalute.to.it; Giglioli, Francesca Romana; Rossetti, Veronica; Ropolo, Roberto [Struttura Complessa Fisica Sanitaria, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Corso Bramante 88, Torino 10126 (Italy); Fiandra, Christian; Ragona, Riccardo [Radiation Oncology Department, University of Turin, Torino 10126 (Italy)

    2016-05-15

    Purpose: The aim of this study was to evaluate various approaches for assessing patient organ doses resulting from radiotherapy cone-beam CT (CBCT), by the use of thermoluminescent dosimeter (TLD) measurements in anthropomorphic phantoms, a Monte Carlo based dose calculation software, and different dose indicators as presently defined. Methods: Dose evaluations were performed on a CBCT Elekta XVI (Elekta, Crawley, UK) for different protocols and anatomical regions. The first part of the study focuses on using PCXMC software (PCXMC 2.0, STUK, Helsinki, Finland) for calculating organ doses, adapting the input parameters to simulate the exposure geometry, and beam dose distribution in an appropriate way. The calculated doses were compared to readouts of TLDs placed in an anthropomorphic Rando phantom. After this validation, the software was used for analyzing organ dose variability associated with patients’ differences in size and gender. At the same time, various dose indicators were evaluated: kerma area product (KAP), cumulative air-kerma at the isocenter (K{sub air}), cone-beam dose index, and central cumulative dose. The latter was evaluated in a single phantom and in a stack of three adjacent computed tomography dose index phantoms. Based on the different dose indicators, a set of coefficients was calculated to estimate organ doses for a range of patient morphologies, using their equivalent diameters. Results: Maximum organ doses were about 1 mGy for head and neck and 25 mGy for chest and pelvis protocols. The differences between PCXMC and TLDs doses were generally below 10% for organs within the field of view and approximately 15% for organs at the boundaries of the radiation beam. When considering patient size and gender variability, differences in organ doses up to 40% were observed especially in the pelvic region; for the organs in the thorax, the maximum differences ranged between 20% and 30%. Phantom dose indexes provided better correlation with organ

  14. Vaginal dose assessment in image-guided brachytherapy for cervical cancer: Can we really rely on dose-point evaluation?

    Science.gov (United States)

    Limkin, Elaine Johanna; Dumas, Isabelle; Rivin Del Campo, Eleonor; Chargari, Cyrus; Maroun, Pierre; Annède, Pierre; Petit, Claire; Seisen, Thomas; Doyeux, Kaya; Tailleur, Anne; Martinetti, Florent; Lefkopoulos, Dimitri; Haie-Meder, Christine; Mazeron, Renaud

    2016-01-01

    Although dose-volume parameters in image-guided brachytherapy have become a standard, the use of posterior-inferior border of the pubic symphysis (PIBS) points has been recently proposed in the reporting of vaginal doses. The aim was to evaluate their pertinence. Nineteen patients who received image-guided brachytherapy after concurrent radiochemotherapy were included. Per treatment, CT scans were performed at Days 2 and 3, with reporting of the initial dwell positions and times. Doses delivered to the PIBS points were evaluated on each plan, considering that they were representative of one-third of the treatment. The movements of the applicator according to the PIBS point were analysed. Mean prescribed doses at PIBS -2, PIBS, PIBS +2 were, respectively, 2.23 ± 1.4, 6.39 ± 6.6, and 31.85 ± 36.06 Gy. Significant differences were observed between the 5 patients with vaginal involvement and the remaining 14 at the level of PIBS +2 and PIBS: +47.60 Gy and +7.46 Gy, respectively (p = 0.023 and 0.03). The variations between delivered and prescribed doses at PIBS points were not significant. However, at International commission on radiation units and measurements rectovaginal point, the delivered dose was decreased by 1.43 ± 2.49 Gy from the planned dose (p = 0.019). The delivered doses at the four points were strongly correlated with the prescribed doses with R(2) ranging from 0.93 to 0.95. The movements of the applicator in regard of the PIBS point assessed with the Digital Imaging and Communications in Medicine coordinates were insignificant. The doses evaluated at PIBS points are not impacted by intrafractional movements. PIBS and PIBS +2 dose points allow distinguishing the plans of patients with vaginal infiltration. Further studies are needed to correlate these parameters with vaginal morbidity. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  15. Dose assessment in pediatric computerized tomography; Avaliacao de doses em tomografia computadorizada pediatrica

    Energy Technology Data Exchange (ETDEWEB)

    Vilarinho, Luisa Maria Auredine Lima

    2004-07-01

    The objective of this work was the evaluation of radiation doses in paediatric computed tomography scans, considering the high doses usually involved and the absence of any previous evaluation in Brazil. Dose values were determined for skull and abdomen examinations, for different age ranges, by using the radiographic techniques routinely used in the clinical centers investigated. Measurements were done using pencil shape ionization chambers inserted in polymethylmethacrylate (PMMA) phantoms. These were compact phantoms of different diameters were specially designed and constructed for this work, which simulate different age ranges. Comparison of results with published values showed that doses were lower than the diagnostic reference levels established to adults exams by the European Commission. Nevertheless, doses in paediatric phantoms were higher than those obtained in adult phantoms. The paediatric dose values obtained in Hospitals A and B were lower than the reference level (DRL) adopted by SHIMPTON for different age ranges. In the range 0 - 0.5 year (neonatal), the values of DLP in Hospital B were 94 por cent superior to the DRL For the 10 years old children the values of CTDI{sub w} obtained were inferior in 89 por cent for skull and 83 por cent for abdomen examinations, compared to the values published by SHRIMPTON and WALL. Our measured CTDI{sub w} values were inferior to the values presented for SHRIMPTON and HUDA, for all the age ranges and types of examinations. It was observed that the normalized dose descriptors values in children in the neonatal range were always superior to the values of doses for the adult patient. In abdomen examinations, the difference was approximately 90% for the effective dose (E) and of 57%.for CTDI{sub w} . (author)

  16. Life cycle assessment and additives: state of knowledge

    DEFF Research Database (Denmark)

    Cycle have been done. These additives belong to 15 chemical groups/chemicals like PFOS, PFOA, NPAA, HBCDD, triclosan and more. The best practice LCIA “consensus” model USEtox was chosen. For only nine of the 17 substances characterisation factors exists and four of these are preliminary (interim). Regarding...

  17. Study on exposure dose according to change of source to image distance and additional filter using abdomen phantom

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Won [Dept. of Radiology, Kyung Hee University Hospital at Gang-dong, Seoul (Korea, Republic of); Son, Jin Hyun [Dept. of Radiological Science, Shingu University, Sungnam (Korea, Republic of)

    2016-09-15

    This study is to minimize the patient dose and maintain the image quality according to change of source to image receptor distance and applying additional filter. In this study, we used the DR system, the tissue-equivalent abdomen phantom and the aluminium filter. The exposure conditions were set to 80 kVp using AEC mode. The collimation size was 16 x 16 inch. The exposure dose were measured 10 times when the SID was changed with 100, 110, 120 and 130 cm, respectively. The pirana 657 for dosimeter was located on center of radiation irradiation. The acquired images were analyzed by using the image J. In the results, the tube current was increased with increasing the SID but ESD was decreased with increasing the SID. The decrease of ESD attribute to use of filter that remove the photon of lower energy. In the histogram results using image J, there were differences between the ESD and the exposure conditions according to change of SID. However, there were not differences in histogram. Therefore, the exposure dose could reduced when set the longer SID. For pediatric exam, the exposure dose could reduced when used the aluminium filter.

  18. Dose assessment intercomparisons within the RENEB network using G0-lymphocyte prematurely condensed chromosomes (PCC assay)

    OpenAIRE

    Terzoudi, Georgia I; Pantelias, Gabriel; Darroudi, Firouz; Barszczewska, Katarzyna; Buraczewska, Iwona; Depuydt, Julie; Georgieva, Dimka; Hadjidekova, Valeria; Hatzi, Vasiliki I.; Karachristou, Ioanna; Karakosta, Maria; Meschini, Roberta; M’kacher, Radhia; Montoro, Alegria; Palitti, Fabrizio

    2017-01-01

    Purpose: Dose assessment intercomparisons within the RENEB network were performed for triage biodosimetry analyzing G0-lymphocyte PCC for harmonization, standardization and optimization of the PCC assay. Materials and methods: Comparative analysis among different partners for dose assessment included shipment of PCC-slides and captured images to construct dose-response curves for up to 6 Gy c-rays. Accident simulation exercises were performed to assess the suitability of the PCC assay by d...

  19. A novel approach to pharmacodynamic assessment of antimicrobial agents: new insights to dosing regimen design.

    Directory of Open Access Journals (Sweden)

    Vincent H Tam

    Full Text Available Pharmacodynamic modeling has been increasingly used as a decision support tool to guide dosing regimen selection, both in the drug development and clinical settings. Killing by antimicrobial agents has been traditionally classified categorically as concentration-dependent (which would favor less fractionating regimens or time-dependent (for which more frequent dosing is preferred. While intuitive and useful to explain empiric data, a more informative approach is necessary to provide a robust assessment of pharmacodynamic profiles in situations other than the extremes of the spectrum (e.g., agents which exhibit partial concentration-dependent killing. A quantitative approach to describe the interaction of an antimicrobial agent and a pathogen is proposed to fill this unmet need. A hypothetic antimicrobial agent with linear pharmacokinetics is used for illustrative purposes. A non-linear functional form (sigmoid Emax of killing consisted of 3 parameters is used. Using different parameter values in conjunction with the relative growth rate of the pathogen and antimicrobial agent concentration ranges, various conventional pharmacodynamic surrogate indices (e.g., AUC/MIC, Cmax/MIC, %T>MIC could be satisfactorily linked to outcomes. In addition, the dosing intensity represented by the average kill rate of a dosing regimen can be derived, which could be used for quantitative comparison. The relevance of our approach is further supported by experimental data from our previous investigations using a variety of gram-negative bacteria and antimicrobial agents (moxifloxacin, levofloxacin, gentamicin, amikacin and meropenem. The pharmacodynamic profiles of a wide range of antimicrobial agents can be assessed by a more flexible computational tool to support dosing selection.

  20. KREAM: Korean Radiation Exposure Assessment Model for Aviation Route Dose

    Science.gov (United States)

    Hwang, J.; Dokgo, K.; Choi, E. J.; Kim, K. C.; Kim, H. P.; Cho, K. S. F.

    2014-12-01

    Since Korean Air has begun to use the polar route from Seoul/ICN airport to New York/JFK airport on August 2006, there are explosive needs for the estimation and prediction against cosmic radiation exposure for Korean aircrew and passengers in South Korea from public. To keep pace with those needs of public, Korean government made the law on safety standards and managements of cosmic radiation for the flight attendants and the pilots in 2013. And we have begun to develop our own Korean Radiation Exposure Assessment Model (KREAM) for aviation route dose since last year funded by Korea Meteorological Administration (KMA). GEANT4 model and NRLMSIS 00 model are used for calculation of the energetic particles' transport in the atmosphere and for obtaining the background atmospheric neutral densities depending on altitude. For prediction the radiation exposure in many routes depending on the various space weather effects, we constructed a database from pre-arranged simulations using all possible combinations of R, S, and G, which are the space weather effect scales provided by the National Oceanic and Atmospheric Administration (NOAA). To get the solar energetic particles' spectrum at the 100 km altitude which we set as a top of the atmospheric layers in the KREAM, we use ACE and GOES satellites' proton flux observations. We compare the results between KREAM and the other cosmic radiation estimation programs such as CARI-6M which is provided by the Federal Aviation Agency (FAA). We also validate KREAM's results by comparison with the measurement from Liulin-6K LET spectrometer onboard Korean commercial flights and Korean Air Force reconnaissance flights.

  1. Toxicity from repeated doses of acetaminophen in children: assessment of causality and dose in reported cases.

    Science.gov (United States)

    Heard, Kennon; Bui, Alison; Mlynarchek, Sara L; Green, Jody L; Bond, G Randall; Clark, Richard F; Kozer, Eran; Koff, Raymond S; Dart, Richard C

    2014-01-01

    Liver injury has been reported in children treated with repeated doses of acetaminophen. The objective of this study was to identify and validate reports of liver injury or death in children younger than 6 years who were administered repeated therapeutic doses of acetaminophen. We reviewed US Poison Center data, peer-reviewed literature, US Food and Drug Administration Adverse Event Reports, and US Manufacturer Safety Reports describing adverse effects after acetaminophen administration. Reports that described hepatic abnormalities (description of liver injury or abnormal laboratory testing) or death after acetaminophen administration to children younger than 6 years were included. The identified reports were double abstracted and then reviewed by an expert panel to determine if the hepatic injury was related to acetaminophen and whether the dose of acetaminophen was therapeutic (≤75 mg/kg) or supratherapeutic. Our search yielded 2531 reports of adverse events associated with acetaminophen use. From these cases, we identified 76 cases of hepatic injury and 26 deaths associated with repeated acetaminophen administration. There were 6 cases of hepatic abnormalities and no deaths associated with what our panel determined to be therapeutic doses. A large proportion of cases could not be fully evaluated due to incomplete case reporting. Although we identified numerous examples of liver injury and death after repeated doses of acetaminophen, all the deaths and all but 6 cases of hepatic abnormalities involved doses more than 75 mg/kg per day. This study suggests that the doses of less than 75 mg/kg per day of acetaminophen are safe for children younger than 6 years.

  2. Dose assessment in environmental radiological protection: State of the art and perspectives.

    Science.gov (United States)

    Stark, Karolina; Goméz-Ros, José M; Vives I Batlle, Jordi; Lindbo Hansen, Elisabeth; Beaugelin-Seiller, Karine; Kapustka, Lawrence A; Wood, Michael D; Bradshaw, Clare; Real, Almudena; McGuire, Corynne; Hinton, Thomas G

    2017-09-01

    Exposure to radiation is a potential hazard to humans and the environment. The Fukushima accident reminded the world of the importance of a reliable risk management system that incorporates the dose received from radiation exposures. The dose to humans from exposure to radiation can be quantified using a well-defined system; its environmental equivalent, however, is still in a developmental state. Additionally, the results of several papers published over the last decade have been criticized because of poor dosimetry. Therefore, a workshop on environmental dosimetry was organized by the STAR (Strategy for Allied Radioecology) Network of Excellence to review the state of the art in environmental dosimetry and prioritize areas of methodological and guidance development. Herein, we report the key findings from that international workshop, summarise parameters that affect the dose animals and plants receive when exposed to radiation, and identify further research needs. Current dosimetry practices for determining environmental protection are based on simple screening dose assessments using knowledge of fundamental radiation physics, source-target geometry relationships, the influence of organism shape and size, and knowledge of how radionuclide distributions in the body and in the soil profile alter dose. In screening model calculations that estimate whole-body dose to biota the shapes of organisms are simply represented as ellipsoids, while recently developed complex voxel phantom models allow organ-specific dose estimates. We identified several research and guidance development priorities for dosimetry. For external exposures, the uncertainty in dose estimates due to spatially heterogeneous distributions of radionuclide contamination is currently being evaluated. Guidance is needed on the level of dosimetry that is required when screening benchmarks are exceeded and how to report exposure in dose-effect studies, including quantification of uncertainties. Further

  3. Radiation Dose-Response Relationships and Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Daniel J.

    2005-07-05

    The notion of a dose-response relationship was probably invented shortly after the discovery of poisons, the invention of alcoholic beverages, and the bringing of fire into a confined space in the forgotten depths of ancient prehistory. The amount of poison or medicine ingested can easily be observed to affect the behavior, health, or sickness outcome. Threshold effects, such as death, could be easily understood for intoxicants, medicine, and poisons. As Paracelsus (1493-1541), the 'father' of modern toxicology said, 'It is the dose that makes the poison.' Perhaps less obvious is the fact that implicit in such dose-response relationships is also the notion of dose rate. Usually, the dose is administered fairly acutely, in a single injection, pill, or swallow; a few puffs on a pipe; or a meal of eating or drinking. The same amount of intoxicants, medicine, or poisons administered over a week or month might have little or no observable effect. Thus, before the discovery of ionizing radiation in the late 19th century, toxicology ('the science of poisons') and pharmacology had deeply ingrained notions of dose-response relationships. This chapter demonstrates that the notion of a dose-response relationship for ionizing radiation is hopelessly simplistic from a scientific standpoint. While useful from a policy or regulatory standpoint, dose-response relationships cannot possibly convey enough information to describe the problem from a quantitative view of radiation biology, nor can they address societal values. Three sections of this chapter address the concepts, observations, and theories that contribute to the scientific input to the practice of managing risks from exposure to ionizing radiation. The presentation begins with irradiation regimes, followed by responses to high and low doses of ionizing radiation, and a discussion of how all of this can inform radiation risk management. The knowledge that is really needed for prediction of

  4. Radiation dose assessment of ACP hot cell in accident

    Energy Technology Data Exchange (ETDEWEB)

    Kook, D. H.; Jeong, W. M.; Koo, J. H.; Jeo, I. J.; Lee, E. P.; Ryu, K. S. [KAERI, Taejon (Korea, Republic of)

    2003-10-01

    The Advanced spent fuel Condition in Process(ACP) is under development for the effective management of spent fuel which had been generated in nuclear plants. The ACP needs a hot cell where most operations will be performed. To give priority to the environments safety, radiation doses evaluations for the radioactive nuclides in accident cases were preliminarily performed with the meteorological data around facility site. Fire accident prevails over several accidnets. Internal Dose and External Dose evaluation according to short dispersion data for that case show a safe margin for regulation limits and SAR limit of IMEF where this facility will be constructed.

  5. Specific gamma-ray dose constants for nuclides important to dosimetry and radiological assessment

    Energy Technology Data Exchange (ETDEWEB)

    Unger, L.M.; Trubey, D.K.

    1982-05-01

    Tables of specific gamma-ray dose constants (the unshielded gamma-ray dose equivalent rate at 1 m from a point source) have been computed for approximately 500 nuclides important to dosimetry and radiological assessment. The half life, the mean attenuation coefficient, and thickness for a lead shield providing 95% dose equivalent attenuation are also listed.

  6. Specific gamma-ray dose constants for nuclides important to dosimetry and radiological assessment

    Energy Technology Data Exchange (ETDEWEB)

    Unger, L.M.; Trubey, D.K.

    1981-09-01

    Tables of specific gamma-ray dose constants (the unshielded gamma-ray dose equivalent rate at 1 m from a point source) have been computed for approximately 500 nuclides important to dosimetry and radiological assessment. The half life, the mean attenuation coefficient, and thickness for a lead shield providing 95% dose equivalent attenuation are also listed.

  7. Aldrin and dieldrin: a reevaluation of the cancer and noncancer dose-response assessments.

    Science.gov (United States)

    Hooker, Eric P; Fulcher, Keri G; Gibb, Herman J

    2014-05-01

    The dose-response analyses of cancer and noncancer health effects of aldrin and dieldrin were evaluated using current methodology, including benchmark dose analysis and the current U.S. Environmental Protection Agency (U.S. EPA) guidance on body weight scaling and uncertainty factors. A literature review was performed to determine the most appropriate adverse effect endpoints. Using current methodology and information, the estimated reference dose values were 0.0001 and 0.00008 mg/kg-day for aldrin and dieldrin, respectively. The estimated cancer slope factors for aldrin and dieldrin were 3.4 and 7.0 (mg/kg-day)(-1), respectively (i.e., about 5- and 2.3-fold lower risk than the 1987 U.S. EPA assessments). Because aldrin and dieldrin are no longer used as pesticides in the United States, they are presumed to be a low priority for additional review by the U.S. EPA. However, because they are persistent and still detected in environmental samples, quantitative risk assessments based on the best available methods are required. Recent epidemiologic studies do not demonstrate a causal association between aldrin and dieldrin and human cancer risk. The proposed reevaluations suggest that these two compounds pose a lower human health risk than currently reported by the U.S. EPA. © 2013 Society for Risk Analysis.

  8. Dose assessment of an accidental exposure at the IPNS

    Energy Technology Data Exchange (ETDEWEB)

    Campos Torres, M.M.

    1995-02-01

    Seven different methods were used to estimate the dose rate to a female worker who was accidentally exposed in the neutron PHOENIX beamline at the IPNS. Theoretical and measured entrance dose ranged from 550 mrem/min to 2850 mrem/min. Theoretical estimates were based on a Monte Carlo simulation of a spectrum provided by IPNS (Crawford Spectrum). Dose measurements were made with TLDs on phantoms and with ionization chambers in a water phantom. Estimates of the whole body total effective dose equivalent (TEDE) rate ranged from 5.2 mrem/min to 840 mrem/min. Assumed and measured quality factors ranged from 2.6 to 11.8. Cytogenetic analyses of blood samples detected no positive exposure. The recommended TEDE rate was 158 mrem/min. The TEDE was 750 mrem.

  9. Dose assessment of an accidental exposure at IPNS

    Energy Technology Data Exchange (ETDEWEB)

    Torres, M.M.C.

    1996-05-01

    Seven different methods were used to estimate the dose rate to a female worker who was accidentally exposed in the neutron PHOENIX beamline at the IPNS. Theoretical and measured entrance dose rates ranged from 550 mrem/min to 2,850 mrem/min. Theoretical estimates were based on a Monte Carlo simulation of a spectrum provided by IPNS (Crawford Spectrum). Dose measurements were made with TLDs on phantoms and with ionization chambers in a water phantom. Estimates of the whole body total effective dose equivalent (TEDE) rate ranged from 5.2 mrem/min to 840 mrem/min. Assumed and measured quality factors ranged from 2.6 to 11.8. Cytogenic analyses of blood samples detected no positive exposure. The recommended TEDE rate was 158 mrem/min. The TEDE was 750 mrem.

  10. Blood compounds irradiation process: assessment of absorbed dose using Fricke and Thermoluminescent dosimetric systems

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Gabriela de Amorim; Squair, Peterson Lima; Pinto, Fausto Carvalho; Belo, Luiz Claudio Meira; Grossi, Pablo Andrade [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN-CNEN/MG), Belo Horizonte, MG (Brazil)], e-mail: gas@cdtn.br, e-mail: pls@cdtn.br, e-mail: fcp@cdtn.br, e-mail: lcmb@cdtn.br, e-mail: pabloag@cdtn.br

    2009-07-01

    The assessment of gamma absorbed doses in irradiation facilities allows the quality assurance and control of the irradiation process. The liability of dose measurements is assign to the metrological procedures adopted including the uncertainty evaluation. Fricke and TLD 800 dosimetric systems were used to measure absorbed dose in the blood compounds using the methodology presented in this paper. The measured absorbed doses were used for evaluating the effectiveness of the irradiation procedure and the gamma dose absorption inside the irradiation room of a gamma irradiation facility. The radiation eliminates the functional and proliferative capacities of donor T-lymphocytes, preventing Transfusion associated graft-versus-host disease (TA-GVHD), a possible complication of blood transfusions. The results show the applicability of such dosimetric systems in quality assurance programs, assessment of absorbed doses in blood compounds and dose uniformity assign to the blood compounds irradiation process by dose measurements in a range between 25 Gy and 100 Gy. (author)

  11. A Probabilistic Approach to Assess External Doses to the Public Considering Spatial Variability of Radioactive Contamination and Interpopulation Differences in Behavior Pattern.

    Science.gov (United States)

    Takahara, Shogo; Iijima, Masashi; Yoneda, Minoru; Shimada, Yoko

    2017-09-08

    Dose assessment is an important issue from the viewpoints of protecting people from radiation exposure and managing postaccident situations adequately. However, the radiation doses received by people cannot be determined with complete accuracy because of the uncertainties and the variability associated with any process of defining individual characteristics and in the dose assessment process itself. In this study, a dose assessment model was developed based on measurements and surveys of individual doses and relevant contributors (i.e., ambient dose rates and behavior patterns) in Fukushima City for four population groups: Fukushima City Office staff, Senior Citizens' Club, Contractors' Association, and Agricultural Cooperative. In addition, probabilistic assessments were performed for these population groups by considering the spatial variability of contamination and interpopulation differences resulting from behavior patterns. As a result of comparison with the actual measurements, the assessment results for participants from the Fukushima City Office agreed with the measured values, thereby validating the model and the approach. Although the assessment results obtained for the Senior Citizens' Club and the Agricultural Cooperative differ partly from the measured values, by addressing further considerations in terms of dose reduction effects due to decontamination and the impact of additional exposure sources in agricultural fields, these results can be improved. By contrast, the measurements obtained for the participants from the Contractors' Association were not reproduced well in the present study. To assess the doses to this group, further investigations of association members' work activities and the related dose reduction effects are needed. © 2017 Society for Risk Analysis.

  12. Fetal and maternal dose assessment for diagnostic scans during pregnancy

    Science.gov (United States)

    Rafat Motavalli, Laleh; Miri Hakimabad, Hashem; Hoseinian Azghadi, Elie

    2016-05-01

    Despite the concerns about prenatal exposure to ionizing radiation, the number of nuclear medicine examinations performed for pregnant women increased in the past decade. This study attempts to better quantify radiation doses due to diagnostic nuclear medicine procedures during pregnancy with the help of our recently developed 3, 6, and 9 month pregnant hybrid phantoms. The reference pregnant models represent the adult female international commission on radiological protection (ICRP) reference phantom as a base template with a fetus in her gravid uterus. Six diagnostic scintigraphy scans using different radiopharmaceuticals were selected as typical diagnostic nuclear medicine procedures. Furthermore, the biokinetic data of radioiodine was updated in this study. A compartment representing iodide in fetal thyroid was addressed explicitly in the biokinetic model. Calculations were performed using the Monte Carlo transport method. Tabulated dose coefficients for both maternal and fetal organs are provided. The comparison was made with the previously published fetal doses calculated for stylized pregnant female phantoms. In general, the fetal dose in previous studies suffers from an underestimation of up to 100% compared to fetal dose at organ level in this study. A maximum of difference in dose was observed for the fetal thyroid compared to the previous studies, in which the traditional models did not contain the fetal thyroid. Cumulated activities of major source organs are primarily responsible for the discrepancies in the organ doses. The differences in fetal dose depend on several other factors including chord length distribution between fetal organs and maternal major source organs, and anatomical differences according to gestation periods. Finally, considering the results of this study, which was based on the realistic pregnant female phantoms, a more informed evaluation of the risks and benefits of the different procedures could be made.

  13. Dose response of whey protein isolate in addition to a typical mixed meal on blood amino acids and hormonal concentrations.

    Science.gov (United States)

    Forbes, Scott C; McCargar, Linda; Jelen, Paul; Bell, Gordon J

    2014-04-01

    The purpose was to investigate the effects of a controlled typical 1-day diet supplemented with two different doses of whey protein isolate on blood amino acid profiles and hormonal concentrations following the final meal. Nine males (age: 29.6 ± 6.3 yrs) completed four conditions in random order: a control (C) condition of a typical mixed diet containing ~10% protein (0.8 g·kg1), 65% carbohydrate, and 25% fat; a placebo (P) condition calorically matched with carbohydrate to the whey protein conditions; a low-dose condition of 0.8 grams of whey protein isolate per kilogram body mass per day (g·kg1·d1; W1) in addition to the typical mixed diet; or a high-dose condition of 1.6 g·kg1·d1 (W2) of supplemental whey protein in addition to the typical mixed diet. Following the final meal, significant (p whey protein supplementation while no changes were observed in the control and placebo conditions. There was no significant group difference for glucose, insulin, testosterone, cortisol, or growth hormone. In conclusion, supplementing a typical daily food intake consisting of 0.8 g of protein·kg1·d1 with a whey protein isolate (an additional 0.8 or 1.6 g·kg1·d1) significantly elevated total amino acids, EAA, BCAA, and leucine but had no effect on glucose, insulin, testosterone, cortisol, or growth hormone following the final meal. Future acute and chronic supplementation research examining the physiological and health outcomes associated with elevated amino acid profiles is warranted.

  14. Dose assessment in accordance with the measured position of size specific dose estimates

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Su [Dept. of Radio-technology, Health Welfare, Wonkwang Health Science University, Iksan (Korea, Republic of); Hong, Sung Wan [Dept. of Radiology, Inje University Ilsan Paik Hospital, Iksan (Korea, Republic of); Kim, Jung Min [Dept. of Radiological Science, Korea University, Seoul (Korea, Republic of)

    2015-12-15

    This study investigated the size specific dose estimates of difference localizer on pediatric CT image. Seventy one cases of pediatric abdomen-pelvic CT (M:F=36:35) were included in this study. Anterior-posterior and lateral diameters were measured in axial CT images. Conversion factors from American Association of Physicists in Medicine (AAPM) report 204 were obtained for effective diameter to determine size specific dose estimate (SSDE) from the CT dose index volume (CTDIvol) recorded from the dose reports. For the localizer of mid-slice SSDE was 107.63% higher than CTDIvol and that of xiphoid-process slices SSDE was higher than 92.91%. The maximum error of iliac crest slices, xiphoid process slices and femur head slices between mid-slices were 7.48%, 17.81% and 14.04%. In conclusion, despite the SSDE of difference localizer has large number of errors, SSDE should be regarded as the primary evaluation tool of the patient radiation in pediatric CT for evaluation.

  15. Computational assessment of effective dose and patient specific doses for kilovoltage stereotactic radiosurgery of wet age-related macular degeneration

    Science.gov (United States)

    Hanlon, Justin Mitchell

    Age-related macular degeneration (AMD) is a leading cause of vision loss and a major health problem for people over the age of 50 in industrialized nations. The current standard of care, ranibizumab, is used to help slow and in some cases stabilize the process of AMD, but requires frequent invasive injections into the eye. Interest continues for stereotactic radiosurgery (SRS), an option that provides a non-invasive treatment for the wet form of AMD, through the development of the IRay(TM) (Oraya Therapeutics, Inc., Newark, CA). The goal of this modality is to destroy choroidal neovascularization beneath the pigment epithelium via delivery of three 100 kVp photon beams entering through the sclera and overlapping on the macula delivering up to 24 Gy of therapeutic dose over a span of approximately 5 minutes. The divergent x-ray beams targeting the fovea are robotically positioned and the eye is gently immobilized by a suction-enabled contact lens. Device development requires assessment of patient effective dose, reference patient mean absorbed doses to radiosensitive tissues, and patient specific doses to the lens and optic nerve. A series of head phantoms, including both reference and patient specific, was derived from CT data and employed in conjunction with the MCNPX 2.5.0 radiation transport code to simulate treatment and evaluate absorbed doses to potential tissues-at-risk. The reference phantoms were used to evaluate effective dose and mean absorbed doses to several radiosensitive tissues. The optic nerve was modeled with changeable positions based on individual patient variability seen in a review of head CT scans gathered. Patient specific phantoms were used to determine the effect of varying anatomy and gaze. The results showed that absorbed doses to the non-targeted tissues were below the threshold levels for serious complications; specifically the development of radiogenic cataracts and radiation induced optic neuropathy (RON). The effective dose

  16. Addition of a low dose of rimonabant to orlistat therapy decreases weight gain and reduces adiposity in dietary obese rats.

    Science.gov (United States)

    Zaitone, Sawsan A; Essawy, Soha

    2012-06-01

    1. The aim of the present study was to determine whether the addition of a subeffective dose of rimonabant (1 mg/kg) to orlistat would be beneficial in the treatment of diet-induced obesity in rats compared with orlistat monotherapy. 2. Male rats were divided into five groups: (i) rats fed a low-fat diet for 4 months; (ii) rats fed a high-fat diet (HFD) for 4 months and treated daily with vehicle (0.2% Tween-80 solution); (iii) orlistat (10 mg/kg per day)-treated HFD-fed rats; (iv) rimonabant (1 mg/kg per day)-treated HFD-fed rats; and (v) HFD-fed rats treated with a combination of orlistat plus rimonabant. Fasting blood glucose, serum insulin, leptin and adiponectin levels were measured. Liver and adiposity indices were calculated and liver and adipose tissues were processed for histological examination. 3. Over the 4 months of the study, vehicle-treated HFD-fed rats exhibited increased cumulative food intake, bodyweight and liver and adiposity indices. Moreover, vehicle-treated HFD-fed rats exhibited a deterioration in liver function and an abnormal lipid profile. Insulin resistance and serum leptin were increased in this group, whereas serum adiponectin levels were decreased. Orlistat monotherapy or combination therapy with orlistat plus rimonabant improved all these parameters. 4. The addition of the low subeffective dose of rimonabant to orlistat therapy ameliorated HFD-induced obesity to a much greater extent than orlistat monotherapy. This combination showed better weight control and metabolic profile compared with orlistat alone. Therefore, the results of the present study encourage reassessment of the use of a low dose of rimonabant to potentiate the effect of orlistat in the clinical management of obesity if proper clinical safety data are available.

  17. Radiological Dose Calculations And Supplemental Dose Assessment Data For Neshap Compliance For SNL Nevada Facilities 1996.

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    Operations of Sandia National Laboratories, Nevada (SNL/NV) at the Tonopah Test Range (TTR) resulted in no planned point radiological releases during 1996. Other releases from SNL/NV included diffuse transuranic sources consisting of the three Clean Slate sites. Air emissions from these sources result from wind resuspension of near-surface transuranic contaminated soil particulates. The total area of contamination has been estimated to exceed 20 million square meters. Soil contamination was documented in an aerial survey program in 1977 (EG&G 1979). Surface contamination levels were generally found to be below 400 pCi/g of combined plutonium-238, plutonium-239, plutonium-240, and americium-241 (i.e., transuranic) activity. Hot spot areas contain up to 43,000 pCi/g of transuranic activity. Recent measurements confirm the presence of significant levels of transuranic activity in the surface soil. An annual diffuse source term of 0.39 Ci of transuranic material was calculated for the cumulative release from all three Clean Slate sites. A maximally exposed individual dose of 1.1 mrem/yr at the TTR airport area was estimated based on the 1996 diffuse source release amounts and site-specific meteorological data. A population dose of 0.86 person-rem/yr was calculated for the local residents. Both dose values were attributable to inhalation of transuranic contaminated dust.

  18. Assessment of patient and occupational dose in established and new applications of MDCT fluoroscopy.

    Science.gov (United States)

    Joemai, Raoul M S; Zweers, Dirk; Obermann, Wim R; Geleijns, Jacob

    2009-04-01

    This study aimed to assess patient dose and occupational dose in established and new applications of MDCT fluoroscopy. Electronic personal dosimeters were used to measure occupational dose equivalent. Effective patient dose was derived from the recorded dose-length product. Acquisition parameters that were observed during CT fluoroscopy (CTF) provided the basis for the estimation of an entrance skin dose profile. Two hundred ten CT-guided interventional procedures were included in the study. The median effective patient dose was 10 mSv (range, 0.1-235 mSv; 107 procedures). The median peak entrance skin dose was 0.4 Sv (0.1-2.1 Sv; 27 procedures). From 547 measurements of occupational dose equivalent, a median occupational effective dose of 3 muSv per procedure was derived for the interventional radiologists and 0.4 muSv per procedure for the assisting radiologists and radiology technologists. The estimated maximum occupational effective dose reached 0.4 mSv. The study revealed high effective patient doses, up to 235 mSv, mainly for relatively new applications such as CTF-guided radiofrequency ablations using MDCT, vertebroplasty, and percutaneous ethanol injections of tumors. Entrance doses were occasionally in the range of the warning level for deterministic skin effects but were always below the threshold for serious deterministic effects. The complexity of the procedure, expected benefits of the treatment, and general health state of the patient contribute to the justification of observed high effective patient doses.

  19. Dose-response modeling : Evaluation, application, and development of procedures for benchmark dose analysis in health risk assessment of chemical substances

    OpenAIRE

    Sand, Salomon

    2005-01-01

    In this thesis, dose-response modeling and procedures for benchmark dose (BMD) analysis in health risk assessment of chemical substances have been investigated. The BMD method has been proposed as an alternative to the NOAEL (no-observedadverse- effect-level) approach in health risk assessment of non-genotoxic agents. According to the BMD concept, a dose-response model is fitted to data and the BMD is defined as the dose causing a predetermined change in response. A lowe...

  20. Retrospective study on the dose assessment in Algeria over a period 1998-2002

    Energy Technology Data Exchange (ETDEWEB)

    Boudena, B.; Chalal, M.; Bellal, A.; Imatoukene, D. [Nuclear Research Center of Algiers (Algeria)

    2006-07-01

    Full text: In Algeria, the assessment of individual doses of workers occupationally exposed to external radiations is made by the national individual monitoring service at the Nuclear Research Center of Algiers (N.R.C.A.) with photographic dosimeter. In this paper, we have undertaken a retrospective study on dose assessment of workers exposed to external radiations involved in medical and industrial activities according to the new occupational dose limits over a period of five consecutive years (1998 2002). This survey has permitted to observe the impact that would have new dose limits once adopted by our legislation. (author)

  1. Radon dose assessment in underground mines in Brazil.

    Science.gov (United States)

    Santos, T O; Rocha, Z; Cruz, P; Gouvea, V A; Siqueira, J B; Oliveira, A H

    2014-07-01

    Underground miners are internally exposed to radon, thoron and their short-lived decay products during the mineral processing. There is also an external exposure due to the gamma emitters present in the rock and dust of the mine. However, the short-lived radon decay products are recognised as the main radiation health risk. When inhaled, they are deposited in the respiratory system and may cause lung cancer. To address this concern, concentration measurements of radon and its progeny were performed, the equilibrium factor was determined and the effective dose received was estimated in six Brazilian underground mines. The radon concentration was measured by using E-PERM, AlphaGUARD and CR-39 detectors. The radon progeny was determined by using DOSEman. The annual effective dose for the miners was estimated according to United Nations Scientific Committee on the Effects of Atomic Radiation methodologies. The mean value of the equilibrium factor was 0.4. The workers' estimated effective dose ranged from 1 to 21 mSv a(-1) (mean 9 mSv a(-1)).

  2. Assessment and interpretation of internal doses: uncertainty and variability.

    Science.gov (United States)

    Paquet, F; Bailey, M R; Leggett, R W; Harrison, J D

    2016-06-01

    Internal doses are calculated on the basis of knowledge of intakes and/or measurements of activity in bioassay samples, typically using reference biokinetic and dosimetric models recommended by the International Commission on Radiological Protection (ICRP). These models describe the behaviour of the radionuclides after ingestion, inhalation, and absorption to the blood, and the absorption of the energy resulting from their nuclear transformations. They are intended to be used mainly for the purpose of radiological protection: that is, optimisation and demonstration of compliance with dose limits. These models and parameter values are fixed by convention and are not subject to uncertainty. Over the past few years, ICRP has devoted a considerable amount of effort to the revision and improvement of models to make them more physiologically realistic. ICRP models are now sufficiently sophisticated for calculating organ and tissue absorbed doses for scientific purposes, and in many other areas, including toxicology, pharmacology and medicine. In these specific cases, uncertainties in parameters and variability between individuals need to be taken into account.

  3. Variability of a peripheral dose among various linac geometries for second cancer risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Joosten, A; Bochud, F; Baechler, S; Moeckli, R [University Institute for Radiation Physics, CHUV and University of Lausanne, Grand-Pre 1, CH-1007 Lausanne (Switzerland); Levi, F [Cancer Epidemiology Unit and Cancer Registries of Vaud and Neuchatel, Institute of Social and Preventive Medecine (IUMSP) and University of Lausanne, CHUV-Falaises 1, CH-1011 Lausanne (Switzerland); Mirimanoff, R-O, E-mail: raphael.moeckli@chuv.ch [Radio-Oncology Department, CHUV and University of Lausanne, Bugnon 21, CH-1011 Lausanne (Switzerland)

    2011-08-21

    Second cancer risk assessment for radiotherapy is controversial due to the large uncertainties of the dose-response relationship. This could be improved by a better assessment of the peripheral doses to healthy organs in future epidemiological studies. In this framework, we developed a simple Monte Carlo (MC) model of the Siemens Primus 6 MV linac for both open and wedged fields that we then validated with dose profiles measured in a water tank up to 30 cm from the central axis. The differences between the measured and calculated doses were comparable to other more complex MC models and never exceeded 50%. We then compared our simple MC model with the peripheral dose profiles of five different linacs with different collimation systems. We found that the peripheral dose between two linacs could differ up to a factor of 9 for small fields (5 x 5 cm{sup 2}) and up to a factor of 10 for wedged fields. Considering that an uncertainty of 50% in dose estimation could be acceptable in the context of risk assessment, the MC model can be used as a generic model for large open fields ({>=}10 x 10 cm{sup 2}) only. The uncertainties in peripheral doses should be considered in future epidemiological studies when designing the width of the dose bins to stratify the risk as a function of the dose.

  4. Digital breast tomosynthesis: Dose and image quality assessment.

    Science.gov (United States)

    Maldera, A; De Marco, P; Colombo, P E; Origgi, D; Torresin, A

    2017-01-01

    The aim of this work was to evaluate how different acquisition geometries and reconstruction parameters affect the performance of four digital breast tomosynthesis (DBT) systems (Senographe Essential - GE, Mammomat Inspiration - Siemens, Selenia Dimensions - Hologic and Amulet Innovality - Fujifilm) on the basis of a physical characterization. Average Glandular Dose (AGD) and image quality parameters such as in-plane/in-depth resolution, signal difference to noise ratio (SDNR) and artefact spread function (ASF) were examined. Measured AGD values resulted below EUREF limits for 2D imaging. A large variability was recorded among the investigated systems: the mean dose ratio DBT/2D ranged between 1.1 and 1.9. In-plane resolution was in the range: 2.2mm(-1)-3.8mm(-1) in chest wall-nipple direction. A worse resolution was found for all devices in tube travel direction. In-depth resolution improved with increasing scan angle but was also affected by the choice of reconstruction and post-processing algorithms. The highest z-resolution was provided by Siemens (50°, FWHM=2.3mm) followed by GE (25°, FWHM=2.8mm), while the Fujifilm HR showed the lowest one, despite its wide scan angle (40°, FWHM=4.1mm). The ASF was dependent on scan angle: smaller range systems showed wider ASF curves; however a clear relationship was not found between scan angle and ASF, due to the different post processing and reconstruction algorithms. SDNR analysis, performed on Fujifilm system, demonstrated that pixel binning improves detectability for a fixed dose/projection. In conclusion, we provide a performance comparison among four DBT systems under a clinical acquisition mode. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  5. TRANSPORTATION CASK RECEIPT AND RETURN FACILITY WORKER DOSE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    V. Arakali

    2005-02-24

    The purpose of this design calculation is to estimate radiation doses received by personnel working in the Transportation Cask Receipt and Return Facility (TCRRF) of the repository including the personnel at the security gate and cask staging areas. This calculation is required to support the preclosure safety analysis (PCSA) to ensure that the predicted doses are within the regulatory limits prescribed by the U.S. Nuclear Regulatory Commission (NRC). The Cask Receipt and Return Facility receives NRC licensed transportation casks loaded with spent nuclear fuel (SNF) and high-level radioactive waste (HLW). The TCRRF operation starts with the receipt, inspection, and survey of the casks at the security gate and the staging areas, and proceeds to the process facilities. The transportation casks arrive at the site via rail cars or trucks under the guidance of the national transportation system. This calculation was developed by the Environmental and Nuclear Engineering organization and is intended solely for the use of Design and Engineering in work regarding facility design. Environmental and Nuclear Engineering personnel should be consulted before using this calculation for purposes other than those stated herein or for use by individuals other than authorized personnel in the Environmental and Nuclear Engineering organization.

  6. Facial exposure dose assessment during intraoral radiography by radiological technologists

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hwan; Yang, Han Joon [Dept. of International Radiological Science, Hallym University of Graduate Studies, Chuncheon (Korea, Republic of)

    2014-09-15

    The study examined the changes in the decreased facial exposure dose for radiological technologists depending on increased distance between the workers and the X-ray tube head during intraoral radiography. First, the facial phantom similar to the human tissues was manufactured. The shooting examination was configured to the maxillary molars for adults (60 kVp, 10 mA, 50 msec) and for children (60 kVp, 10 mA, 20 msec), and the chamber was fixed where the facial part of the radiation worker would be placed using the intraoral radiography equipment. The distances between the X-ray tube head and the phantom were set to 10 cm, 15 cm, 20 cm, 25 cm, 30 cm, 35 cm, and 40 cm. The phantom was radiated 20 times with each examination condition and the average scattered doses were examined. The rate at the distance of 40 cm decreased by about 92.6% to 7.43% based on the scattered rays radiated at the distance of 10 cm under the adult conditions. The rate at the distance of 40 cm decreased by about 97.6% to 2.58% based on the scattered rays radiated at the distance of 10 cm under the children conditions. Protection from the radiation exposure was required during the dental radiographic examination.

  7. EMP Attachment 3 DOE-SC PNNL Site Dose Assessment Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, Sandra F.

    2011-12-21

    This Dose Assessment Guidance (DAG) describes methods to use to determine the Maximally-Exposed Individual (MEI) location and to estimate dose impact to that individual under the U.S. Department of Energy Office of Science (DOE-SC) Pacific Northwest National Laboratory (PNNL) Site Environmental Monitoring Plan (EMP). This guidance applies to public dose from radioactive material releases to the air from PNNL Site operations. This document is an attachment to the Pacific Northwest National Laboratory (PNNL) Environmental Monitoring Plan (EMP) and describes dose assessment guidance for radiological air emissions. The impact of radiological air emissions from the U.S. Department of Energy Office of Science (DOE-SC) PNNL Site is indicated by dose estimates to a maximally exposed member of the public, referred to as the maximally exposed individual (MEI). Reporting requirements associated with dose to members of the public from radiological air emissions are in 40 CFR Part 61.94, WAC 246-247-080, and DOE Order 458.1. The DOE Order and state standards for dose from radioactive air emissions are consistent with U.S. Environmental Protection Agency (EPA) dose standards in 40 CFR 61.92 (i.e., 10 mrem/yr to a MEI). Despite the fact that the current Contract Requirements Document (CRD) for the DOE-SC PNNL Site operations does not include the requirement to meet DOE CRD 458.1, paragraph 2.b, public dose limits, the DOE dose limits would be met when EPA limits are met.

  8. Assessing doses to terrestrial wildlife at a radioactive waste disposal site: Inter-comparison of modelling approaches

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, M.P., E-mail: mathew.johansen@ansto.gov.au [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW, 2232 (Australia); Barnett, C.L., E-mail: clb@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster (United Kingdom); Beresford, N.A., E-mail: nab@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster (United Kingdom); Brown, J.E., E-mail: justin.brown@nrpa.no [Norwegian Radiation Protection Authority, Oesteraas (Norway); Cerne, M., E-mail: marko.cerne@ijs.si [Jozef Stefan Institute, Ljubljana (Slovenia); Howard, B.J., E-mail: bjho@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster (United Kingdom); Kamboj, S., E-mail: skamboj@anl.gov [Argonne National Laboratory, IL (United States); Keum, D.-K., E-mail: dkkeum@kaeri.re.kr [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Smodis, B. [Jozef Stefan Institute, Ljubljana (Slovenia); Twining, J.R., E-mail: jrt@ansto.gov.au [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW, 2232 (Australia); Vandenhove, H., E-mail: hvandenh@sckcen.be [Belgian Nuclear Research Centre, Mol (Belgium); Vives i Batlle, J., E-mail: jvbatll@sckcen.be [Belgian Nuclear Research Centre, Mol (Belgium); Wood, M.D., E-mail: m.d.wood@salford.ac.uk [University of Salford, Manchester (United Kingdom); Yu, C., E-mail: cyu@anl.gov [Argonne National Laboratory, IL (United States)

    2012-06-15

    Radiological doses to terrestrial wildlife were examined in this model inter-comparison study that emphasised factors causing variability in dose estimation. The study participants used varying modelling approaches and information sources to estimate dose rates and tissue concentrations for a range of biota types exposed to soil contamination at a shallow radionuclide waste burial site in Australia. Results indicated that the dominant factor causing variation in dose rate estimates (up to three orders of magnitude on mean total dose rates) was the soil-to-organism transfer of radionuclides that included variation in transfer parameter values as well as transfer calculation methods. Additional variation was associated with other modelling factors including: how participants conceptualised and modelled the exposure configurations (two orders of magnitude); which progeny to include with the parent radionuclide (typically less than one order of magnitude); and dose calculation parameters, including radiation weighting factors and dose conversion coefficients (typically less than one order of magnitude). Probabilistic approaches to model parameterisation were used to encompass and describe variable model parameters and outcomes. The study confirms the need for continued evaluation of the underlying mechanisms governing soil-to-organism transfer of radionuclides to improve estimation of dose rates to terrestrial wildlife. The exposure pathways and configurations available in most current codes are limited when considering instances where organisms access subsurface contamination through rooting, burrowing, or using different localised waste areas as part of their habitual routines. - Highlights: Black-Right-Pointing-Pointer Assessment of modelled dose rates to terrestrial biota from radionuclides. Black-Right-Pointing-Pointer The substantial variation among current approaches is quantifiable. Black-Right-Pointing-Pointer The dominant variable was soil

  9. Using the Monte Carlo method for assessing the tissue and organ doses of patients in dental radiography

    Science.gov (United States)

    Makarevich, K. O.; Minenko, V. F.; Verenich, K. A.; Kuten, S. A.

    2016-05-01

    This work is dedicated to modeling dental radiographic examinations to assess the absorbed doses of patients and effective doses. For simulating X-ray spectra, the TASMIP empirical model is used. Doses are assessed on the basis of the Monte Carlo method by using MCNP code for voxel phantoms of ICRP. The results of the assessment of doses to individual organs and effective doses for different types of dental examinations and features of X-ray tube are presented.

  10. Oral propranolol for infantile hemangiomas: a prospective study on the role of 48-hour Holter monitoring in additional safety assessment.

    Science.gov (United States)

    Petrovic, Jelena; Trifunovic, Branislav; Vukomanovic, Goran; Topalovic, Mirko; Trajkovic, Goran; Parezanović, Vojislav

    2017-09-01

    Oral propranolol has been recently approved for infantile hemangiomas (IHs), but potential side effects stay a challenge. We sought to make an additional assessment on oral propranolol safety for this indication. Prospective study included 108 infants consecutively treated for IHs at the University Children's Hospital Tirsova, Belgrade from January 2010 to December 2013. Propranolol was administered orally at a daily dose of 0.5 mg/kg and doubled every 48 hours in the absence of side effects until reaching the maximum dose of 2 mg/kg daily. Systolic and diastolic blood pressure and heart rate were measured every 48 hours with clinical observation. Heart rate was monitored by standard electrocardiogram (ECG) and 48-hour Holter ECG. Statistically significant, but asymptomatic decreases in systolic blood pressure and heart rate recorded by Holter ECG were observed during the first doubling of dose and then remained stable. Arrhythmias were not detected. Despite mild sleep disturbance observed in 31% of infants in the hospital milieu, Holter monitoring indicated circadian rhythm maintenance. Oral propranolol for IHs does not remarkably affect heart rhythm including circadian variations throughout hospital initiation. Therefore, there is no necessity for Holter monitoring in additional safety assessment.

  11. Assessment of PAtient Doses During mAmmogrAPhy PrActice At ...

    African Journals Online (AJOL)

    2011-11-11

    Nov 11, 2011 ... specific tests on the mammography x-ray unit, image quality assessment, consistency tests, and radiation dose ... The equipment has manual and AEC systems, Mo/Mo ..... inclusion of the denser pectoral muscle in the image.

  12. Early treatment with addition of low dose prednisolone to methotrexate improves therapeutic outcome in severe psoriatic arthritis

    Directory of Open Access Journals (Sweden)

    Vikram K Mahajan

    2013-01-01

    Full Text Available Psoriatic arthritis (PsA is increasingly being recognized to cause progressive joint damage and disability. PsA unresponsive to non-steroidal anti-inflammatory drugs (NSAIDs, the conventional first-line choice of treatment, is usually managed with disease-modifying antirheumatic drugs (DMARDs especially methotrexate. An 18-year-old HIV-negative male had progressively severe PsA of 4-month duration that was nearly confining him to a wheel chair. He did not respond to multiple NSAIDs, alone or in combination with methotrexate (15 mg/week, given for 4 weeks. Addition of prednisolone (10 mg on alternate days controlled his symptoms within a week. The NSAIDs could be withdrawn after 4 weeks as the treatment progressed. The doses were tapered for methotrexate (5 mg/week and prednisolone (2.5 mg on alternate days every 8 weekly subsequently during 15 months of follow-up without recurrence/deformities or drug toxicity. For years, the use of corticosteroids in psoriasis has been criticized for their propensity to exacerbate the skin disease on withdrawal. However, monitored use of corticosteroids, even in low doses, combined with DMARDs may be a good therapeutic option in early stage of the PsA rather than ′steroid rescue′ later. This will help in early control of joint inflammation, prevent joint damage and maintain long-term good functional capacity and quality of life. This may be useful when the cost or availability of biologics precludes their use. However, we discourage the use of corticosteroids as monotherapy.

  13. Boron Diffused Thermoluminescent Surface Layer in LiF TLDs for Skin Dose Assessments

    DEFF Research Database (Denmark)

    Christensen, Poul; Majborn, Benny

    1980-01-01

    A new high-temperature glow peak produced in a thin surface layer of LiF TLDs by diffusion of boron into the LiF material has been studied for skin dose assessments in personnel dosimetry.......A new high-temperature glow peak produced in a thin surface layer of LiF TLDs by diffusion of boron into the LiF material has been studied for skin dose assessments in personnel dosimetry....

  14. Appropriate Use of Effective Dose in Radiation Protection and Risk Assessment.

    Science.gov (United States)

    Fisher, Darrell R; Fahey, Frederic H

    2017-08-01

    Effective dose was introduced by the ICRP for the single, over-arching purpose of setting limits for radiation protection. Effective dose is a derived quantity or mathematical construct and not a physical, measurable quantity. The formula for calculating effective dose to a reference model incorporates terms to account for all radiation types, organ and tissue radiosensitivities, population groups, and multiple biological endpoints. The properties and appropriate applications of effective dose are not well understood by many within and outside the health physics profession; no other quantity in radiation protection has been more confusing or misunderstood. According to ICRP Publication 103, effective dose is to be used for "prospective dose assessment for planning and optimization in radiological protection, and retrospective demonstration of compliance for regulatory purposes." In practice, effective dose has been applied incorrectly to predict cancer risk among exposed persons. The concept of effective dose applies generally to reference models only and not to individual subjects. While conceived to represent a measure of cancer risk or heritable detrimental effects, effective dose is not predictive of future cancer risk. The formula for calculating effective dose incorporates committee-selected weighting factors for radiation quality and organ sensitivity; however, the organ weighting factors are averaged across all ages and both genders and thus do not apply to any specific individual or radiosensitive subpopulations such as children and young women. Further, it is not appropriate to apply effective dose to individual medical patients because patient-specific parameters may vary substantially from the assumptions used in generalized models. Also, effective dose is not applicable to therapeutic uses of radiation, as its mathematical underpinnings pertain only to observed late (stochastic) effects of radiation exposure and do not account for short-term adverse

  15. Reduced-dose CT protocol for the assessment of cerebral vasospasm

    Energy Technology Data Exchange (ETDEWEB)

    Bricout, N.; Estrade, L.; Boustia, F.; Kalsoum, E.; Pruvo, J.P.; Leclerc, X. [Hopital Roger Salengro, CHRU de Lille, Department of Neuroradiology, Universite Lille Nord de France, Lille cedex (France)

    2015-12-15

    Despite the increased radiation dose, multimodal CT including noncontrast CT (NCT), CT angiography (CTA), and perfusion CT (PCT) remains a useful tool for the diagnosis of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH). The aim of this study was to assess the radiation dose and the image quality between a standard-dose and a reduced-dose multimodal CT protocol. The study group consisted of 26 aSAH patients with a suspicion of DCI on clinical examination and transcranial doppler. Two different CT protocols were used: a standard-dose protocol (NCT 120 kV, 350 mAs; CTA 100 kV, 250 mAs; PCT 80 kV, 200 mAs) from August 2011 to October 2013 (n = 13) and a reduced-dose protocol (NCT 100 kV, 400 mAs; CTA 100 kV, 220 mAs; PCT 80 kV, 180 mAs) from November 2013 to May 2014 (n = 13). Dose-length product (DLP), effective dose, volume CT dose index (CTDI), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and overall image quality were determined for each examination. The overall image quality was judged as good or excellent in all cases. The reduced-dose protocol allowed a 15 % decrease in both the median total DLP (2438 vs 2898 mGy cm, p < 0.0001) and the effective dose as well as a significant decrease in median CTDI of 23, 31, and 10 % for NCT, CTA, and CTP, respectively. This dose reduction did not result in significant alteration of SNR (except for NCT) or CNR between groups. The present study showed that the reduced-dose multimodal CT protocol enabled a significant reduction of radiation dose without image quality impairment. (orig.)

  16. Epidemiological methods for assessing dose-response and dose-effect relationships

    DEFF Research Database (Denmark)

    Kjellström, Tord; Grandjean, Philippe

    2007-01-01

    and their compounds. An entirely new structure and illustrations represent the vast array of advancements made since the last edition. Special emphasis has been placed on the toxic effects in humans with chapters on the diagnosis, treatment and prevention of metal poisoning. This up-to-date reference provides easy...... and Toxicity Carcinogenicity of Metal Compounds Immunotoxicology of Metals Reproductive and Developmental Toxicity of Metals Ecotoxicology of Metals - Sources, Transport, and Effects in the Ecosystem Risk Assessment Diagnosis and Treatment of Metal Poisoning - General Aspects Principles for Prevention...... of the Toxic Effects of Metals Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Chromium Cobalt Copper Gallium and Semiconductor Compounds Germanium Indium Iron Lead Manganese Mercury Molybdenum Nickel Palladium Platinum Selenium Silver Tellurium Thallium Tin Titanium Tungsten Uranium Vanadium Zinc...

  17. Assessment of potential doses to workers during postulated accident conditions at the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hoover, M.D.; Farrell, R.F. [DOE, Carlsbad, NM (United States); Newton, G.J.

    1995-12-01

    The recent 1995 WIPP Safety Analysis Report (SAR) Update provided detailed analyses of potential radiation doses to members of the public at the site boundary during postulated accident scenarios at the U.S. Department of Energy`s Waste Isolation Pilot Plant (WIPP). The SAR Update addressed the complete spectrum of potential accidents associated with handling and emplacing transuranic waste at WIPP, including damage to waste drums from fires, punctures, drops, and other disruptions. The report focused on the adequacy of the multiple layers of safety practice ({open_quotes}defense-in-depth{close_quotes}) at WIPP, which are designed to (1) reduce the likelihood of accidents and (2) limit the consequences of those accidents. The safeguards which contribute to defense-in-depth at WIPP include a substantial array of inherent design features, engineered controls, and administrative procedures. The SAR Update confirmed that the defense-in-depth at WIPP is adequate to assure the protection of the public and environment. As a supplement to the 1995 SAR Update, we have conducted additional analyses to confirm that these controls will also provide adequate protection to workers at the WIPP. The approaches and results of the worker dose assessment are summarized here. In conformance with the guidance of DOE Standard 3009-94, we emphasize that use of these evaluation guidelines is not intended to imply that these numbers constitute acceptable limits for worker exposures under accident conditions. However, in conjunction with the extensive safety assessment in the 1995 SAR Update, these results indicate that the Carlsbad Area Office strategy for the assessment of hazards and accidents assures the protection of workers, members of the public, and the environment.

  18. Dosimetry experiences and lessons learned for radiation dose assessment in Korean nuclear power plants.

    Science.gov (United States)

    Choi, Jong Rak; Kim, Hee Geun; Kong, Tae Young; Son, Jung Kwon

    2013-07-01

    Since the first Korean nuclear power plant (NPP), Kori 1, commenced operation in 1978, a total of 21 NPPs had been put into operation in Korea by the end of 2011. Radiation doses of NPP workers have been periodically evaluated and controlled within the prescribed dose limit. Radiation dose assessment is carried out monthly by reading personal dosemeters for external radiation exposure, which have traceability in compliance with strict technical guidelines. In the case of the internal radiation exposure, workers who have access to the possible area of polluted air are also evaluated for their internal dose after maintenance task. In this article, the overall situation and experience for the assessment and distribution of radiation doses in Korean NPPs is described.

  19. Establishment of a radiological dose assessment system for HANARO emergency preparedness

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Han; Han, Moon Hee; Suh, Kyung Suk; Hwang, Won Tae; Choi, Young Gil

    1999-12-01

    A radiological dose assessment system has been established to calculate the three-dimensional wind field based on the observed data at meteorological towers, and to calculate the exposure dose in the radiological accidents or for emergency training. The wind fields program has been constructed to calculate the real-time wind field using the atmospheric stability and the diffusion parameters based on the meteorological data sets measured from two meteorological towers. The result is separated into the effective dose and thyroid dose with 4 age groups such as infant, children, teenage and adult. Dose rate and cumulated dose for above each termare calculated and repeated for the prediction and modification according to the elapsed time. The evaluated data sets are displayed on the map around KAERI site with social and environmental information which is made with GIS. (author)

  20. Risk assessment for the combinational effects of food color additives: neural progenitor cells and hippocampal neurogenesis.

    Science.gov (United States)

    Park, Mikyung; Park, Hee Ra; Kim, So Jung; Kim, Min-Sun; Kong, Kyoung Hye; Kim, Hyun Soo; Gong, Ein Ji; Kim, Mi Eun; Kim, Hyung Sik; Lee, Byung Mu; Lee, Jaewon

    2009-01-01

    In 2006, the Korea Food and Drug Administration reported that combinations of dietary colors such as allura red AC (R40), tartrazine (Y4), sunset yellow FCF (Y5), amaranth (R2), and brilliant blue FCF (B1) are widely used in food manufacturing. Although individual tar food colors are controlled based on acceptable daily intake (ADI), there is no apparent information available for how combinations of these additives affect food safety. In the current study, the potencies of single and combination use of R40, Y4, Y5, R2, and B1 were examined on neural progenitor cell (NPC) toxicity, a biomarker for developmental stage, and neurogenesis, indicative of adult central nervous system (CNS) functions. R40 and R2 reduced NPC proliferation and viability in mouse multipotent NPC, in the developing CNS model. Among several combinations tested in mouse model, combination of Y4 and B1 at 1000-fold higher than average daily intake in Korea significantly decreased numbers of newly generated cells in adult mouse hippocampus, indicating potent adverse actions on hippocampal neurogenesis. However, other combinations including R40 and R2 did not affect adult hippocampal neurogenesis in the dentate gyrus. Evidence indicates that single and combination use of most tar food colors may be safe with respect to risk using developmental NPC and adult hippocampal neurogenesis. However, the response to excessively high dose combination of Y4 and B1 is suggestive of synergistic effects to suppress proliferation of NPC in adult hippocampus. Data indicated that combinations of tar colors may adversely affect both developmental and adult hippocampal neurogenesis; thus, further extensive studies are required to assess the safety of these additive combinations.

  1. 4D cone beam CT-based dose assessment for SBRT lung cancer treatment

    Science.gov (United States)

    Cai, Weixing; Dhou, Salam; Cifter, Fulya; Myronakis, Marios; Hurwitz, Martina H.; Williams, Christopher L.; Berbeco, Ross I.; Seco, Joao; Lewis, John H.

    2016-01-01

    The purpose of this research is to develop a 4DCBCT-based dose assessment method for calculating actual delivered dose for patients with significant respiratory motion or anatomical changes during the course of SBRT. To address the limitation of 4DCT-based dose assessment, we propose to calculate the delivered dose using time-varying (‘fluoroscopic’) 3D patient images generated from a 4DCBCT-based motion model. The method includes four steps: (1) before each treatment, 4DCBCT data is acquired with the patient in treatment position, based on which a patient-specific motion model is created using a principal components analysis algorithm. (2) During treatment, 2D time-varying kV projection images are continuously acquired, from which time-varying ‘fluoroscopic’ 3D images of the patient are reconstructed using the motion model. (3) Lateral truncation artifacts are corrected using planning 4DCT images. (4) The 3D dose distribution is computed for each timepoint in the set of 3D fluoroscopic images, from which the total effective 3D delivered dose is calculated by accumulating deformed dose distributions. This approach is validated using six modified XCAT phantoms with lung tumors and different respiratory motions derived from patient data. The estimated doses are compared to that calculated using ground-truth XCAT phantoms. For each XCAT phantom, the calculated delivered tumor dose values generally follow the same trend as that of the ground truth and at most timepoints the difference is less than 5%. For the overall delivered dose, the normalized error of calculated 3D dose distribution is generally less than 3% and the tumor D95 error is less than 1.5%. XCAT phantom studies indicate the potential of the proposed method to accurately estimate 3D tumor dose distributions for SBRT lung treatment based on 4DCBCT imaging and motion modeling. Further research is necessary to investigate its performance for clinical patient data.

  2. Assessment of inhalation dose sensitivity by physicochemical properties of airborne particulates containing naturally occurring radioactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Si Young; Choi, Cheol Kyu; Kim, Yong Geon; Choi, Won Chul; Kim, Kwang Pyo [Kyung Hee University, Seoul (Korea, Republic of)

    2015-12-15

    Facilities processing raw materials containing naturally occurring radioactive materials (NORM) may give rise to enhanced radiation dose to workers due to chronic inhalation of airborne particulates. Internal radiation dose due to particulate inhalation varies depending on particulate properties, including size, shape, density, and absorption type. The objective of the present study was to assess inhalation dose sensitivity to physicochemical properties of airborne particulates. Committed effective doses to workers resulting from inhalation of airborne particulates were calculated based on International Commission on Radiological Protection 66 human respiratory tract model. Inhalation dose generally increased with decreasing particulate size. Committed effective doses due to inhalation of 0.01μm sized particulates were higher than doses due to 100μm sized particulates by factors of about 100 and 50 for {sup 238}U and {sup 230}Th, respectively. Inhalation dose increased with decreasing shape factor. Shape factors of 1 and 2 resulted in dose difference by about 18 %. Inhalation dose increased with particulate mass density. Particulate mass densities of 11 g·cm{sup -3} and 0.7 g·cm{sup -3} resulted in dose difference by about 60 %. For {sup 238}U, inhalation doses were higher for absorption type of S, M, and F in that sequence. Committed effective dose for absorption type S of {sup 238}U was about 9 times higher than dose for absorption F. For {sup 230}Th, inhalation doses were higher for absorption type of F, M, and S in that sequence. Committed effective dose for absorption type F of {sup 230}Th was about 16 times higher than dose for absorption S. Consequently, use of default values for particulate properties without consideration of site specific physiochemical properties may potentially skew radiation dose estimates to unrealistic values up to 1-2 orders of magnitude. For this reason, it is highly recommended to consider site specific working materials and

  3. Assessment of adequacy of hemodialysis dose at a Palestinian hospital

    Directory of Open Access Journals (Sweden)

    Heba Adas

    2014-01-01

    Full Text Available Adequacy of hemodialysis improves patient survival, quality of life and biochemical outcomes and minimizes disease complications and hospitalizations. This study was an observational cross-sectional study that was conducted in July 2012. Blood tests, weight and blood pressure were measured before and after hemodialysis. Single-pool Kt/V and urea reduction ratio (URR were calculated. The targets based on the National Kidney Foundation Disease Outcomes Quality Initiative (KDOQI Clinical Practice Guidelines were Kt/V ≥ 1.2 and URR ≥ 65%. Of the 64 patients, 41 (64.1% were males. The mean age of the patients was 58.13 ± 17.2 years. The mean body mass index (BMI was 25.04 ± 5.01 kg/m 2 . The mean Kt/V and URR were 1.06 ± 0.05 and 54.4 ± 19.3, respectively. There was no significant difference between men and women (1.06 ± 0.47 versus 1.04 ± 0.55, P = 0.863 and (54.7 ± 19.59 versus 53.81 ± 19.17, P = 0.296. Only 25 (39.1% patients achieved the Kt/V goal and only 22 (34.4% had target URR, and there was no significant association between hemodialysis adequacy and any of the variables such as sex, age, presence of chronic diseases or BMI. Serum potassium levels post-dialysis were significantly lower in patients who reached the target Kt/V (mean = 3.44 ± 0.48 versus 3.88 ± 0.48, P = 0.001. Most patients were inadequately dialyzed and a large percentage of the patients did not attain the targets. Attempts to achieve the desired goals are necessary. It is important to calculate Kt/V or URR and individualize the dialysis doses for each patient.

  4. ANDROS: A code for Assessment of Nuclide Doses and Risks with Option Selection

    Energy Technology Data Exchange (ETDEWEB)

    Begovich, C.L.; Sjoreen, A.L.; Ohr, S.Y.; Chester, R.O.

    1986-11-01

    ANDROS (Assessment of Nuclide Doses and Risks with Option Selection) is a computer code written to compute doses and health effects from atmospheric releases of radionuclides. ANDROS has been designed as an integral part of the CRRIS (Computerized Radiological Risk Investigation System). ANDROS reads air concentrations and environmental concentrations of radionuclides to produce tables of specified doses and health effects to selected organs via selected pathways (e.g., ingestion or air immersion). The calculation may be done for an individual at a specific location or for the population of the whole assessment grid. The user may request tables of specific effects for every assessment grid location. Along with the radionuclide concentrations, the code requires radionuclide decay data, dose and risk factors, and location-specific data, all of which are available within the CRRIS. This document is a user manual for ANDROS and presents the methodology used in this code.

  5. Development of environmental dose assessment system (EDAS) code of PC version

    CERN Document Server

    Taki, M; Kobayashi, H; Yamaguchi, T

    2003-01-01

    A computer code (EDAS) was developed to assess the public dose for the safety assessment to get the license of nuclear reactor operation. This code system is used for the safety analysis of public around the nuclear reactor in normal operation and severe accident. This code was revised and composed for personal computer user according to the Nuclear Safety Guidelines reflected the ICRP1990 recommendation. These guidelines are revised by Nuclear Safety Commission on March, 2001, which are 'Weather analysis guideline for the safety assessment of nuclear power reactor', 'Public dose around the facility assessment guideline corresponding to the objective value for nuclear power light water reactor' and 'Public dose assessment guideline for safety review of nuclear power light water reactor'. This code has been already opened for public user by JAERI, and English version code and user manual are also prepared. This English version code is helpful for international cooperation concerning the nuclear safety assessme...

  6. Assessment of Mini-dose Succinylcholine Effect on Facilitating Laryngeal Mask Airway Insertion

    Directory of Open Access Journals (Sweden)

    Aghamohammadi Dawood

    2013-03-01

    Full Text Available Introduction: Laryngeal Mask Airway (LMA has gained wide acceptance for routine airway management and with increasing emphasis on day care surgery it is widely used. The aim of this study was to assess the effects of mini dose succinylcholine (0.1mg/kg with semi-inflated cuff on facilitation of laryngeal mask airway insertion in order to achieve more satisfaction yet less complications . Methods: In a randomized double-blinded study, sixty ASA 1, 2 and 3 patients aged 20-60 years scheduled for urologic surgical procedures were included. Thirty patients received succinylcholine (Group S, and thirty received 0.9% sodium choride as a placebo (Group C. Results: Coughing occured in 33.3% of patients in the control group and there was no incidence in succ group (P=0.002. Head or limb movement occurred in 70% of the patients in the control group vs. 10% in succ group (P<0.001. Laryngospasm occurred in 36.6 % of the patients in the control group but there was no incidence in succ group (P=0.004. Additional propofol was required in 53% of the patients in control group vs. 10% for succ group (P=0.001. Ease of insertion and first successfull attempt of LMA were achieved in 93.3% and 90% of the patients respectively in group S (P<0.05. Myalgia and sore throat occurred in 66.7 % of patients in the group C in comparison with 33.3% in group S (P=0.06. Conclusion: The combination of propofol with mini dose succinylcholine, provided a significantly better method for LMA insertion, while reduced propofol doses were needed and number of attempts decreased.

  7. An assessment of the secondary neutron dose in the passive scattering proton beam facility of the national cancer center

    Energy Technology Data Exchange (ETDEWEB)

    Han, Sang Eun [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Cho, Gyuseong [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Lee, Se Byeong [Proton Therapy Center, National Cancer Center, Goyang (Korea, Republic of)

    2017-06-15

    The purpose of this study is to assess the additional neutron effective dose during passive scattering proton therapy. Monte Carlo code (Monte Carlo N-Particle 6) simulation was conducted based on a precise modeling of the National Cancer Center's proton therapy facility. A three-dimensional neutron effective dose profile of the interior of the treatment room was acquired via a computer simulation of the 217.8-MeV proton beam. Measurements were taken with a 3He neutron detector to support the simulation results, which were lower than the simulation results by 16% on average. The secondary photon dose was about 0.8% of the neutron dose. The dominant neutron source was deduced based on flux calculation. The secondary neutron effective dose per proton absorbed dose ranged from 4.942 ± 0.031 mSv/Gy at the end of the field to 0.324 ± 0.006 mSv/Gy at 150 cm in axial distance.

  8. Development of a real-time radiological dose assessment system

    Energy Technology Data Exchange (ETDEWEB)

    Han, Moon Hee; Lee, Young Bok; Kim, Eun Han; Suh, Kyung Suk; Hwang, Won Tae

    1997-01-01

    Inspection and repair of tower structure and lift, instrument calibration have been done. Wireless data transmission to MIPS (Meteorological Information Processing System) has been done after collection in the DAS where environmental assessment can be done by the developed simulation programs in both cases of normal operation and emergency. Wind direction, wind speed, temperature, humidity at 67m, 27m, and 10m height and temperature, humidity, atmospheric pressure, solar radiation, precipitation, and visibility at surface have been measured analyzed with statistical methods. At the site, the prevailing wind directions were SW in spring and summer, NNW in winter season. (author). 6 refs., 9 tabs., 4 figs.

  9. Radiological dose assessments at the Kennedy Space Center

    Energy Technology Data Exchange (ETDEWEB)

    Firstenberg, H.; Jubach, R.; Bartram, B.; Vaughan, F.

    1989-01-01

    This paper discusses the application of an atmospheric transport and diffusion model for launch window and safety risk assessment studies in support of the Galileo (which is scheduled for the October/November 1989 period) and Ulysses (scheduled for {approximately}1 yr after Galileo) missions at the Kennedy Space Center (KSC). The model is resident in the EMERGE software system developed by NUS Corporation and modified for the U.S. Department of Energy (DOE) to provide real-time and safety analyses report support for the launches. The application is unique in that the model accommodates the varied amount of meteorological data at KSC and Cape Canaveral and includes a site-specific algorithm to account for local-scale circulations. This paper focuses on the Galileo mission application, including discussions of the use of the meteorological data available at KSC, integration of the EMERGE sea-breeze algorithm, and examples of real-time and safety analyses report assessments. The Galileo spacecraft is to be launched toward Jupiter using the space shuttle.

  10. Dose-response assessment using the benchmark dose approach of changes in hepatic EROD activity for individual polychlorinated biphenyl congeners

    Energy Technology Data Exchange (ETDEWEB)

    Fattore, E.; Fanelli, R. [' ' Mario Negri' ' Institute for Pharmacological Research, Milan (Italy); Chu, I. [Safe Environments Programme, Healthy Environments and Consumer Safety Branch, Tunney' s Pasture, Ottawa, ON (Canada); Sand, S.; Haakansson, H. [Institute of Environmental Medicine, Karolinska Institutet, Stockholm (Sweden); Falk-Filippson, A. [Swedish Chemicals Inspectorate, Sundbyberg (Sweden)

    2004-09-15

    The benchmark dose (BMD) approach was proposed as an alternative to the no-observedadverse- effect-level (NOAEL) or the lowest-observed-adverse-effect-level (LOAEL) as point of departure (POD) for extrapolation of data from animal studies to the low dose human exposure situation. In the risk assessment process using the NOAEL/LOAEL parameter, the reference dose (RfD) or the admissible daily intake (ADI) is obtained by dividing the NOAEL/LOAEL value by uncertainty factors. The uncertainty factors are incorporated in order to take into account variability in the sensitivity of different species, inter-individual differences in sensitivity within the human population, and variability in experimental data. In the BMD approach a dose-response curve is fitted to experimental data (Figure 1) and the BMD is calculated from the equation of the curve as the dose corresponding to a predetermined change in the response defined as the benchmark response (BMR). The 95% lower confidence bound of the BMD, usually referred to as BMDL, can be used as the POD in the extrapolation process to get a RfD or an ADI. The advantages of using the BMD approach are many. First, all the experimental data are utilized to construct the doseresponse curve; second, the variability and uncertainty are taken into account by incorporating standard deviations of means; and third, it represents a single methodology for cancer and noncancer endpoints. In this study the BMD methodology was applied to evaluate dose-response data of seven chlorinated biphenyl (CB) congeners (Table 1), some of which are dioxin-like while others are not. The data were obtained from subchronic dietary exposure studies in male and female Sprague Dawley rats. Elevation in ethoxyresorufin-O-deethylase (EROD) activity was selected as biological response because it is known to be an endpoint sensitive to the exposure of dioxin-like PCBs. Since this response is not an adverse effect per se, in this paper we will refer to the no

  11. 3D-printed applicators for high dose rate brachytherapy: Dosimetric assessment at different infill percentage.

    Science.gov (United States)

    Ricotti, Rosalinda; Vavassori, Andrea; Bazani, Alessia; Ciardo, Delia; Pansini, Floriana; Spoto, Ruggero; Sammarco, Vittorio; Cattani, Federica; Baroni, Guido; Orecchia, Roberto; Jereczek-Fossa, Barbara Alicja

    2016-12-01

    Dosimetric assessment of high dose rate (HDR) brachytherapy applicators, printed in 3D with acrylonitrile butadiene styrene (ABS) at different infill percentage. A low-cost, desktop, 3D printer (Hamlet 3DX100, Hamlet, Dublin, IE) was used for manufacturing simple HDR applicators, reproducing typical geometries in brachytherapy: cylindrical (common in vaginal treatment) and flat configurations (generally used to treat superficial lesions). Printer accuracy was investigated through physical measurements. The dosimetric consequences of varying the applicator's density by tuning the printing infill percentage were analysed experimentally by measuring depth dose profiles and superficial dose distribution with Gafchromic EBT3 films (International Specialty Products, Wayne, NJ). Dose distributions were compared to those obtained with a commercial superficial applicator. Measured printing accuracy was within 0.5mm. Dose attenuation was not sensitive to the density of the material. Surface dose distribution comparison of the 3D printed flat applicators with respect to the commercial superficial applicator showed an overall passing rate greater than 94% for gamma analysis with 3% dose difference criteria, 3mm distance-to-agreement criteria and 10% dose threshold. Low-cost 3D printers are a promising solution for the customization of the HDR brachytherapy applicators. However, further assessment of 3D printing techniques and regulatory materials approval are required for clinical application. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  12. Assessment of prospective foodchain doses from radioactive discharges from BNFL Sellafield

    Energy Technology Data Exchange (ETDEWEB)

    Ould-Dada, Z. E-mail: zitouni.ould-dada@foodstandards.gsi.gov.uk; Tucker, S.; Webbe-Wood, D.; Mondon, K.; Hunt, J

    2002-07-01

    This paper presents the method used by the UK Food Standards Agency (FSA) to assess the potential impact of proposed radioactive discharges from the Sellafield nuclear site on food and determine their acceptability. It explains aspects of a cautious method that has been adopted to reflect the UK government policy and uncertainties related to people's habits with regard to food production and consumption. Two types of ingestion doses are considered in this method: 'possible' and 'probable' doses. The method is specifically applied to Sellafield discharge limits and calculated possible and probable ingestion doses are presented and discussed. Estimated critical group ingestion doses are below the dose limit and constraint set for members of the public. The method may be subject to future amendments to take account of changes in government policy and the outcome of a recent Consultative Exercise on Dose Assessments carried out by FSA. Uncertainties inherent in dose assessments are discussed and quantified wherever possible.

  13. Assessment of the dose from radon and its decay products in the Bozkov dolomite cave.

    Science.gov (United States)

    Rovenská, K; Thinová, L; Zdímal, V

    2008-01-01

    The dose from radon and its progeny remains a frequently discussed problem. ICRP 65 provides a commonly used methodology to calculate the dose from radon. Our work focuses on a cave environment and on assessing the doses in public open caves. The differences in conditions (aerosol size distribution, humidity, radon and its progeny ratio, etc.) are described by the so-called cave factor j. The cave factor is used to correct the dose for workers which is calculated using the ICRP 65 recommendation. In this work, the authors have brought together measured data of aerosol size distribution, unattached and attached fraction activity, and have calculated the so-called cave factor for the Bozkov dolomite cave environment. The dose conversion factors based on measured data and used for evaluating the cave factor were calculated by LUDEP software, which implements HRTM ICRP66.

  14. Realistic retrospective dose assessments to members of the public around Spanish nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, M.A., E-mail: majg@csn.es [Consejo de Seguridad Nuclear (CSN), Pedro Justo Dorado Dellmans 11, E-28040 Madrid (Spain); Martin-Valdepenas, J.M.; Garcia-Talavera, M.; Martin-Matarranz, J.L.; Salas, M.R.; Serrano, J.I.; Ramos, L.M. [Consejo de Seguridad Nuclear (CSN), Pedro Justo Dorado Dellmans 11, E-28040 Madrid (Spain)

    2011-11-15

    In the frame of an epidemiological study carried out in the influence areas around the Spanish nuclear facilities (ISCIII-CSN, 2009. Epidemiological Study of The Possible Effect of Ionizing Radiations Deriving from The Operation of Spanish Nuclear Fuel Cycle Facilities on The Health of The Population Living in Their Vicinity. Final report December 2009. Ministerio de Ciencia e Innovacion, Instituto de Salud Carlos III, Consejo de Seguridad Nuclear. Madrid. Available from: (http://www.csn.es/images/stories/actualidad{sub d}atos/especiales/epidemiologico/epidemiological{sub s}tudy.pdf)), annual effective doses to public have been assessed by the Spanish Nuclear Safety Council (CSN) for over 45 years using a retrospective realistic-dose methodology. These values are compared with data from natural radiation exposure. For the affected population, natural radiation effective doses are in average 2300 times higher than effective doses due to the operation of nuclear installations (nuclear power stations and fuel cycle facilities). When considering the impact on the whole Spanish population, effective doses attributable to nuclear facilities represent in average 3.5 x 10{sup -5} mSv/y, in contrast to 1.6 mSv/y from natural radiation or 1.3 mSv/y from medical exposures. - Highlights: > Most comprehensive dose assessment to public by nuclear facilities ever done in Spain. > Dose to public is dominated by liquid effluent pathways for the power stations. > Dose to public is dominated by Rn inhalation for milling and mining facilities. > Average annual doses to public in influence areas are negligible (10 {mu}Sv/y or less). > Doses from facilities average 3.5 x 10{sup -2} {mu}Sv/y per person onto whole Spanish population.

  15. Qualitative and quantitative approaches in the dose-response assessment of genotoxic carcinogens.

    Science.gov (United States)

    Fukushima, Shoji; Gi, Min; Kakehashi, Anna; Wanibuchi, Hideki; Matsumoto, Michiharu

    2016-05-01

    Qualitative and quantitative approaches are important issues in field of carcinogenic risk assessment of the genotoxic carcinogens. Herein, we provide quantitative data on low-dose hepatocarcinogenicity studies for three genotoxic hepatocarcinogens: 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and N-nitrosodiethylamine (DEN). Hepatocarcinogenicity was examined by quantitative analysis of glutathione S-transferase placental form (GST-P) positive foci, which are the preneoplastic lesions in rat hepatocarcinogenesis and the endpoint carcinogenic marker in the rat liver medium-term carcinogenicity bioassay. We also examined DNA damage and gene mutations which occurred through the initiation stage of carcinogenesis. For the establishment of points of departure (PoD) from which the cancer-related risk can be estimated, we analyzed the above events by quantitative no-observed-effect level and benchmark dose approaches. MeIQx at low doses induced formation of DNA-MeIQx adducts; somewhat higher doses caused elevation of 8-hydroxy-2'-deoxyquanosine levels; at still higher doses gene mutations occurred; and the highest dose induced formation of GST-P positive foci. These data indicate that early genotoxic events in the pathway to carcinogenesis showed the expected trend of lower PoDs for earlier events in the carcinogenic process. Similarly, only the highest dose of IQ caused an increase in the number of GST-P positive foci in the liver, while IQ-DNA adduct formation was observed with low doses. Moreover, treatment with DEN at low doses had no effect on development of GST-P positive foci in the liver. These data on PoDs for the markers contribute to understand whether genotoxic carcinogens have a threshold for their carcinogenicity. The most appropriate approach to use in low dose-response assessment must be approved on the basis of scientific judgment.

  16. Radiological dose assessment related to management of naturally occurring radioactive materials generated by the petroleum industry

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.P.; Blunt, D.L.; Williams, G.P. [Argonne National Lab., IL (United States). Environmental Assessment Div.; Tebes, C.L. [Univ. of Illinois, Urbana, IL (United States)

    1996-09-01

    A preliminary radiological dose assessment of equipment decontamination, subsurface disposal, landspreading, equipment smelting, and equipment burial was conducted to address concerns regarding the presence of naturally occurring radioactive materials (NORM) in production waste streams. The assessment estimated maximum individual dose equivalents for workers and the general public. Sensitivity analyses of certain input parameters also were conducted. On the basis of this assessment, it is concluded that (1) regulations requiring workers to wear respiratory protection during equipment cleaning operations are likely to result in lower worker doses, (2) underground injection and downhole encapsulation of NORM wastes present a negligible risk to the general public, and (3) potential doses to workers and the general public related to smelting NORM-contaminated equipment can be controlled by limiting the contamination level of the initial feed. It is recommended that (1) NORM wastes be further characterized to improve studies of potential radiological doses; (2) states be encouraged to permit subsurface disposal of NORM more readily, provided further assessments support this study; results; (3) further assessment of landspreading NORM wastes be conducted; and (4) the political, economic, sociological, and nonradiological issues related to smelting NORM-contaminated equipment be studied to fully examine the feasibility of this disposal option.

  17. The debate on the use of linear no threshold for assessing the effects of low doses

    Energy Technology Data Exchange (ETDEWEB)

    Tubiana, M; Aurengo, A; Averbeck, D; Masse, R [Centre Antoine Beclere, 45 rue des Saints-Peres, 75006 Paris (France)

    2006-09-15

    From December 2004 to July 2005, three reports on the effects of low doses of ionising radiation were released: ICRP (2004), the joint report of the French Academies of Science and Medicine (Tubiana et al 2005), and a report from the American Academy of Sciences (BEIR VII 2005). These reports quote the same recent articles on the biological effects of low doses, yet their conclusions diverge. The French report concludes that recent biological data show that the efficacy of defense mechanisms is modulated by dose and dose rate and that linear no threshold (LNT) is no longer plausible. The ICRP and the BEIR VII reports recognise that there are biologic arguments against LNT but feel that there are not sufficient biological proofs against it to change risk assessment methodology and subsequent regulatory policy based on LNT. They point out the remaining uncertainties and the lack of mechanistic explanations of phenomena such as low dose hyperlethality or the adaptive response. In this context, a critical analysis of the available data is necessary. The epidemiological data and the experimental data challenge the validity of the LNT hypothesis for assessing the carcinogenic effect of low doses, but do not allow its exclusion. Therefore, the main criteria for selecting the most reliable dose-effect relationship from a scientific point of view should be based on biological data. Their analysis should help one to understand the current controversy. (opinion)

  18. The debate on the use of linear no threshold for assessing the effects of low doses.

    Science.gov (United States)

    Tubiana, M; Aurengo, A; Averbeck, D; Masse, R

    2006-09-01

    From December 2004 to July 2005, three reports on the effects of low doses of ionising radiation were released: ICRP (2004), the joint report of the French Academies of Science and Medicine (Tubiana et al 2005), and a report from the American Academy of Sciences (BEIR VII 2005). These reports quote the same recent articles on the biological effects of low doses, yet their conclusions diverge. The French report concludes that recent biological data show that the efficacy of defense mechanisms is modulated by dose and dose rate and that linear no threshold (LNT) is no longer plausible. The ICRP and the BEIR VII reports recognise that there are biologic arguments against LNT but feel that there are not sufficient biological proofs against it to change risk assessment methodology and subsequent regulatory policy based on LNT. They point out the remaining uncertainties and the lack of mechanistic explanations of phenomena such as low dose hyperlethality or the adaptive response. In this context, a critical analysis of the available data is necessary. The epidemiological data and the experimental data challenge the validity of the LNT hypothesis for assessing the carcinogenic effect of low doses, but do not allow its exclusion. Therefore, the main criteria for selecting the most reliable dose-effect relationship from a scientific point of view should be based on biological data. Their analysis should help one to understand the current controversy.

  19. Evaluation of the neutron spectrum and dose assessment around the venus reactor.

    Science.gov (United States)

    Coeck, Michèle; Vermeersch, Fernand; Vanhavere, Filip

    2005-01-01

    An assessment of the neutron field near the VENUS reactor is made in order to evaluate the neutron dose to the operators, particularly in an area near the reactor shielding and in the control room. Therefore, a full MCNPX model of the shielding geometry was developed. The source term used in the simulation is derived from a criticality calculation done beforehand. Calculations are compared to routine neutron dose rate measurements and show good agreement. The MCNPX model developed easily allows core adaptations in order to evaluate the effect of future core configuration on the neutron dose to the operators.

  20. A test strategy for the assessment of additive attributed toxicity of tobacco products.

    Science.gov (United States)

    Kienhuis, Anne S; Staal, Yvonne C M; Soeteman-Hernández, Lya G; van de Nobelen, Suzanne; Talhout, Reinskje

    2016-08-01

    The new EU Tobacco Product Directive (TPD) prohibits tobacco products containing additives that are toxic in unburnt form or that increase overall toxicity of the product. This paper proposes a strategy to assess additive attributed toxicity in the context of the TPD. Literature was searched on toxicity testing strategies for regulatory purposes from tobacco industry and governmental institutes. Although mainly traditional in vivo testing strategies have been applied to assess toxicity of unburnt additives and increases in overall toxicity of tobacco products due to additives, in vitro tests combined with toxicogenomics and validated using biomarkers of exposure and disease are most promising in this respect. As such, tests are needed that are sensitive enough to assess additive attributed toxicity above the overall toxicity of tobacco products, which can associate assay outcomes to human risk and exposure. In conclusion, new, sensitive in vitro assays are needed to conclude whether comparable testing allows for assessment of small changes in overall toxicity attributed to additives. A more pragmatic approach for implementation on a short-term is mandated lowering of toxic emission components. Combined with risk assessment, this approach allows assessment of effectiveness of harm reduction strategies, including banning or reducing of additives.

  1. Revised series of stylized anthropometric phantoms for internal and external radiation dose assessment

    Science.gov (United States)

    Han, Eunyoung

    At present, the dosimetry systems of both the International Commission on Radiological Protection, and the Society of Nuclear Medicine's Medical Internal Radiation Dose Committee utilize a series of stylized or mathematical anthropometric models of patient anatomy developed in 1987 at the Oak Ridge National Laboratory (ORNL). In this study, substantial revisions to the ORNL phantom series are reported with tissue compositions, tissue densities, and organ masses adjusted to match their most recent values in the literature. In addition, both the ICRP and MIRD systems of internal dosimetry implicitly consider that electron and beta-particle energy emitted within the source organs of the patient are fully deposited within these organs. With the development of the revised ORNL phantom series, three additional applications were explored as part of this dissertation research. First, the phantoms were used in combination to assess external radiation exposures to family members caring or interacting with patients released from the hospital following radionuclide therapy with I-131. Values of family member effective dose are then compared to values obtained using NRC guidance and based on a simple point-source methodology which ignores the effects of photon attenuation and scatter within both the source individual (patient) and the target individual (family member). Second, the anatomical structures of the extrathoracic airways and thoracic airways (exclusive of the lungs themselves) have been included in the entire revised ORNL phantom series of pediatric individuals. Values of cross-region photon dose are explored for use in radioactive aerosol inhalation exposures to members of the general public, and comparisons are made to values given by the ICRP in which surrogate organ assignments were made in the absence of explicit models of these airways. Finally, the revised ORNL phantoms of the adult male and adult female are used to determine internal photon exposures to

  2. Development of internal dose assessment procedure for workers in industries using raw materials containing naturally occurring radioactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Cheol Kyu; KIm, Yong Geon; Ji, Seung Woo; Kim, Kwang Pyo [College of Engineering, Kyung Hee University, Yongin (Korea, Republic of); Koo, Bon Cheol; Chang, Byung Uck [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-09-15

    It is necessary to assess radiation dose to workers due to inhalation of airborne particulates containing naturally occurring radioactive materials (NORM) to ensure radiological safety required by the Natural Radiation Safety Management Act. The objective of this study is to develop an internal dose assessment procedure for workers at industries using raw materials containing natural radionuclides. The dose assessment procedure was developed based on harmonization, accuracy, and proportionality. The procedure includes determination of dose assessment necessity, preliminary dose estimation, airborne particulate sampling and characterization, and detailed assessment of radiation dose. The developed dose assessment procedure is as follows. Radioactivity concentration criteria to determine dose assessment necessity are 10 Bq·g-1 for 40K and 1 Bq·g-1 for the other natural radionuclides. The preliminary dose estimation is performed using annual limit on intake (ALI). The estimated doses are classified into 3 groups (<0.1 mSv, 0.1-0.3 mSv, and >0.3 mSv). Air sampling methods are determined based on the dose estimates. Detailed dose assessment is performed using air sampling and particulate characterization. The final dose results are classified into 4 different levels (<0.1 mSv, 0.1-0.3 mSv, 0.3-1 mSv, and >1 mSv). Proper radiation protection measures are suggested according to the dose level. The developed dose assessment procedure was applied for NORM industries in Korea, including coal combustion, phosphate processing, and monazite handing facilities. The developed procedure provides consistent dose assessment results and contributes to the establishment of optimization of radiological protection in NORM industries.

  3. Environmental dose rate assessment of ITER using the Monte Carlo method

    Directory of Open Access Journals (Sweden)

    Karimian Alireza

    2014-01-01

    Full Text Available Exposure to radiation is one of the main sources of risk to staff employed in reactor facilities. The staff of a tokamak is exposed to a wide range of neutrons and photons around the tokamak hall. The International Thermonuclear Experimental Reactor (ITER is a nuclear fusion engineering project and the most advanced experimental tokamak in the world. From the radiobiological point of view, ITER dose rates assessment is particularly important. The aim of this study is the assessment of the amount of radiation in ITER during its normal operation in a radial direction from the plasma chamber to the tokamak hall. To achieve this goal, the ITER system and its components were simulated by the Monte Carlo method using the MCNPX 2.6.0 code. Furthermore, the equivalent dose rates of some radiosensitive organs of the human body were calculated by using the medical internal radiation dose phantom. Our study is based on the deuterium-tritium plasma burning by 14.1 MeV neutron production and also photon radiation due to neutron activation. As our results show, the total equivalent dose rate on the outside of the bioshield wall of the tokamak hall is about 1 mSv per year, which is less than the annual occupational dose rate limit during the normal operation of ITER. Also, equivalent dose rates of radiosensitive organs have shown that the maximum dose rate belongs to the kidney. The data may help calculate how long the staff can stay in such an environment, before the equivalent dose rates reach the whole-body dose limits.

  4. Assessment of low-dose radiotoxicity in microorganisms and higher organisms

    Energy Technology Data Exchange (ETDEWEB)

    Obeid, Muhammad Hassan

    2016-01-11

    This work was dedicated to quantify and distinguish the radio- and chemitoxic effects of environmentally relevant low doses of uranium on the metabolism of microorganisms and multicellular organisms by a modern and highly sensitive microcalorimetry. In such low-dose regime, lethality is low or absent. Therefore, quantitative assays based on survival curves cannot be employed, particularly for multicellular organisms. Even in the case of microbial growth, where individual cells may be killed by particle radiation, classical toxicity assessments based on colony counting are not only extremely time-consuming but also highly error-prone. Therefore, measuring the metabolic activity of the organism under such kinds of conditions would give an extremely valuable quantitative measure of viability that is based on life cell monitoring, rather than determining lethality at higher doses and extrapolating it to the low dose regime. The basic concept is simple as it relies on the metabolic heat produced by an organism during development, growth or replication as an inevitable byproduct of all biochemical processes. A metabolic effect in this concept is defined as a change in heat production over time in the presence of a stressor, such as a heavy metal. This approach appeared to be particular versatile for the low dose regime. Thus, the thesis attempted in this case to measure the enthalpy production of a bacterial population as a whole to derive novel toxicity concepts. In the following chapters, an introduction about the properties of ionizing radiation will be briefly presented, in addition to a review about the isothermal calorimetry and its application in studying the bacterial growth. Later in chapter 2, the effect of uranium on the metabolic activity of three different bacterial strains isolated form a uranium mining waste pile together with a reference strain that is genetically related to them will be investigated. Due to the lack of published dedicated calibration

  5. Osteosarcoma: a randomized, prospective trial of the addition of ifosfamide and/or muramyl tripeptide to cisplatin, doxorubicin, and high-dose methotrexate.

    Science.gov (United States)

    Meyers, Paul A; Schwartz, Cindy L; Krailo, Mark; Kleinerman, Eugenie S; Betcher, Donna; Bernstein, Mark L; Conrad, Ernest; Ferguson, William; Gebhardt, Mark; Goorin, Allen M; Harris, Michael B; Healey, John; Huvos, Andrew; Link, Michael; Montebello, Joseph; Nadel, Helen; Nieder, Michael; Sato, Judith; Siegal, Gene; Weiner, Michael; Wells, Robert; Wold, Lester; Womer, Richard; Grier, Holcombe

    2005-03-20

    To determine whether the addition of ifosfamide and/or muramyl tripeptide (MTP) encapsulated in liposomes to cisplatin, doxorubicin, and high-dose methotrexate (HDMTX) could improve the probability for event-free survival (EFS) in newly diagnosed patients with osteosarcoma (OS). Six hundred seventy-seven patients with OS without clinically detectable metastatic disease were treated with one of four prospectively randomized treatments. All patients received identical cumulative doses of cisplatin, doxorubicin, and HDMTX and underwent definitive surgical resection of the primary tumor. Patients were randomly assigned to receive or not to receive ifosfamide and/or MTP in a 2 double dagger 2 factorial design. The primary end point for analysis was EFS. Patients treated with the standard arm of therapy had a 3-year EFS of 71%. We could not analyze the results by factorial design because we observed an interaction between the addition of ifosfamide and the addition of MTP. The addition of MTP to standard chemotherapy achieved a 3-year EFS rate of 68%. The addition of ifosfamide to standard chemotherapy achieved a 3-year EFS rate of 61%. The addition of both ifosfamide and MTP resulted in a 3-year EFS rate of 78%. The addition of ifosfamide in this dose schedule to standard chemotherapy did not enhance EFS. The addition of MTP to chemotherapy might improve EFS, but additional clinical and laboratory investigation will be necessary to explain the interaction between ifosfamide and MTP.

  6. RADIATION HYGIENIC MONITORING AND ASSESSMENT OF POPULATION DOSES IN RADIOACTIVELY CONTAMINATED AREAS OF TULA REGION

    Directory of Open Access Journals (Sweden)

    T. M. Chichura

    2016-01-01

    Full Text Available The goal. The analyses of radiation hygienic monitoring conducted in Tula region territories affected by the Chernobyl NPP accident regarding cesium-137 and strontium- 90 in the local foodstuffs and the analyses of populational annual effective dose. The materials and methods. The survey was conducted in Tula Region since 1997 to 2015. Over that period, more than fifty thousand samples of the main foodstuffs from the post-Chernobyl contaminated area were analyzed. Simultaneously with that, the external gamma - radiation dose rate was measured in the fixed control points. The dynamics of cesium -137 and strontium-90 content in foodstuffs were assessed along with the maximum values of the mean annual effective doses to the population and the contribution of the collective dose from medical exposures into the structure of the annual effective collective dose to the population. The results. The amount of cesium-137 and strontium -90 in the local foodstuffs was identified. The external gamma- radiation dose rate values were found to be stable and not exceeding the natural fluctuations range typical for the middle latitudes of Russia’s European territory. The maximum mean annual effective dose to the population reflects the stable radiation situation and does not exceed the permissible value of 1 mSv. The contribution of the collective dose from medical exposures of the population has been continuously reducing as well as the average individual dose to the population per one medical treatment under the annual increase of the medical treatments quantities. The conclusion. There is no exceedance of the admissible levels of cesium-137 and strontium- 90 content in the local foodstuffs. The mean annual effective dose to the population has decreased which makes it possible to transfer the settlements affected by the Chernobyl NPP accident to normal life style. This is covered by the draft concept of the settlements’ transfer to normal life style.

  7. Effect of low-dose CT and iterative reconstruction on trabecular bone microstructure assessment

    Science.gov (United States)

    Kopp, Felix K.; Baum, Thomas; Nasirudin, Radin A.; Mei, Kai; Garcia, Eduardo G.; Burgkart, Rainer; Rummeny, Ernst J.; Bauer, Jan S.; Noël, Peter B.

    2016-03-01

    The trabecular bone microstructure is an important factor in the development of osteoporosis. It is well known that its deterioration is one effect when osteoporosis occurs. Previous research showed that the analysis of trabecular bone microstructure enables more precise diagnoses of osteoporosis compared to a sole measurement of the mineral density. Microstructure parameters are assessed on volumetric images of the bone acquired either with high-resolution magnetic resonance imaging, high-resolution peripheral quantitative computed tomography or high-resolution computed tomography (CT), with only CT being applicable to the spine, which is one of clinically most relevant fracture sites. However, due to the high radiation exposure for imaging the whole spine these measurements are not applicable in current clinical routine. In this work, twelve vertebrae from three different donors were scanned with standard and low radiation dose. Trabecular bone microstructure parameters were assessed for CT images reconstructed with statistical iterative reconstruction (SIR) and analytical filtered backprojection (FBP). The resulting structure parameters were correlated to the biomechanically determined fracture load of each vertebra. Microstructure parameters assessed for low-dose data reconstructed with SIR significantly correlated with fracture loads as well as parameters assessed for standard-dose data reconstructed with FBP. Ideal results were achieved with low to zero regularization strength yielding microstructure parameters not significantly different from those assessed for standard-dose FPB data. Moreover, in comparison to other approaches, superior noise-resolution trade-offs can be found with the proposed methods.

  8. Assessment of temporal trend of radiation dose to the public living in the large area contaminated with radioactive materials after a nuclear power plant accident

    Energy Technology Data Exchange (ETDEWEB)

    Go, A Ra; Kim, Min Jun; Kim, Kwang Pyo [Dept. of Nuclear Engineering, Kyung Hee University, Seoul (Korea, Republic of); Cho, Nam Chan; Seol, Jeung Gun [Radiation Safety Team, Korea Electric Power Corporation Nuclear Fuel, Seoul (Korea, Republic of)

    2015-12-15

    It has been about 5 years since the Fukushima nuclear power plant accident, which contaminated large area with radioactive materials. It is necessary to assess radiation dose to establish evacuation areas and to set decontamination goal for the large contaminated area. In this study, we assessed temporal trend of radiation dose to the public living in the large area contaminated with radioactive materials after the Fukushima nuclear power plant accident. The dose assessment was performed based on Chernobyl model and RESRAD model for two evacuation lift areas, Kawauchi and Naraha. It was reported that deposition densities in the areas were 4.3-96 kBq m{sup -2} for {sup 134}Cs, 1.4-300 kBq m{sup -2} for {sup 137}Cs, respectively. Radiation dose to the residents depended on radioactive cesium concentrations in the soil, ranging 0.11-2.4 mSv y{sup -1} at Kawauchi area and 0.69-1.1 mSv y{sup -1} at Naraha area in July 2014. The difference was less than 5% in radiation doses estimated by two different models. Radiation dose decreased with calendar time and the decreasing slope varied depending on dose assessment models. Based on the Chernobyl dosimetry model, radiation doses decreased with calendar time to about 65% level of the radiation dose in 2014 after 1 year, 11% level after 10 years, and 5.6% level after 30 years. RESRAD dosimetry model more slowly decreased radiation dose with time to about 85% level after 1 year, 40% level after 10 years, and 15% level after 30 years. The decrease of radiation dose can be mainly attributed into radioactive decays and environmental transport of the radioactive cesium. Only environmental transports of radioactive cesium without consideration of radioactive decays decreased radiation dose additionally 43% after 1 year, 72% after 3 years, 80% after 10 years, and 83% after 30 years. Radiation doses estimated with cesium concentration in the soil based on Chernobyl dosimetry model were compared with directly measured radiation doses

  9. CTDI versus new AAPM metrics to assess doses in CT: a case study

    Energy Technology Data Exchange (ETDEWEB)

    Campelo, M.C.S., E-mail: maria.macalidi@gmail.com [Pontificia Universidade Catolica de Sao Paulo (PUC-SP), SP (Brazil); Silva, M.C., E-mail: marciac.silvag@gmail.com [Hospital Israelita Albert Einstein (HIAE), Sao Paulo, SP (Brazil); Terini, R.A., E-mail: ricardoaterini@gmail.com [Universidade de Sao Paulo (LABEND/USP), SP (Brazil). Laboratorio de Ensaios Nao-Destrutivos

    2016-07-01

    In modern CT, CTDI100 measurements would underestimate accumulated dose at the gantry center. AAPM TG 111 report proposed improved metrics for CT dosimetry, mainly for helical and wide beam width scanning. In this study, a methodology to assess CT dose, inspired on TG 111, was applied. Dosimeters were firstly calibrated in lab in beams like those utilized clinically. Using a reference 0.6cc Farmer chamber, two CT “pencil” chambers were calibrated in P{sub KL} by substitution method. Results showed differences ≤ 2% in the calibration coefficients, for three collimation apertures. A small 0.6cc chamber was calibrated in air kerma with this setup, without any collimator. After this, in a private Brazilian hospital, the small chamber was applied in dosimetry tests of a CT scanner, according to TG 111, determining Dose profiles and Equilibrium dose free-in-air (D{sub eq,air}) for some protocols and pitch values. Results showed that D{sub eq,air} increased when reducing pitch and Equilibrium dose-pitch product free in air (p.D{sub eq,air}) remain constant. In measurements with a 450mm CT phantom, differences between Planar Average Equilibrium Dose (D{sub eq,p}) and CTDIvol ranged between 30-37%. This occurs because CTDI{sub vol} cannot include dose profile 'tail' contribution, caused by scattering in phantom, especially for wide beam widths. (author)

  10. Preclinical assessment of HIV vaccines and microbicides by repeated low-dose virus challenges.

    Directory of Open Access Journals (Sweden)

    Roland R Regoes

    2005-08-01

    Full Text Available BACKGROUND: Trials in macaque models play an essential role in the evaluation of biomedical interventions that aim to prevent HIV infection, such as vaccines, microbicides, and systemic chemoprophylaxis. These trials are usually conducted with very high virus challenge doses that result in infection with certainty. However, these high challenge doses do not realistically reflect the low probability of HIV transmission in humans, and thus may rule out preventive interventions that could protect against "real life" exposures. The belief that experiments involving realistically low challenge doses require large numbers of animals has so far prevented the development of alternatives to using high challenge doses. METHODS AND FINDINGS: Using statistical power analysis, we investigate how many animals would be needed to conduct preclinical trials using low virus challenge doses. We show that experimental designs in which animals are repeatedly challenged with low doses do not require unfeasibly large numbers of animals to assess vaccine or microbicide success. CONCLUSION: Preclinical trials using repeated low-dose challenges represent a promising alternative approach to identify potential preventive interventions.

  11. The Thule accident: Assessment of radiation doses from terrestrial radioactive contamination

    Energy Technology Data Exchange (ETDEWEB)

    Ulbak, K. (National Institute of Radiation Protection, Herlev (Denmark))

    2011-12-15

    Risoe DTU has carried out research on the terrestrial contamination in the Thule area after the radioactive contents of four nuclear weapons were dispersed following the crash of an American B-52 bomber in 1968. The results of Risoe DTU's studies are described in the report Thule-2007 - Investigation of radioactive pollution on land, which covers all measurements that were carried out on land in Thule in the years 2003, 2006, 2007 and 2008. The present report uses Risoe DTU's report as a basis for assessing radiation doses and consequently the risk for individuals as a result of terrestrial radioactive contamination in the Thule area. The assessment of radiation doses involves a number of conservative assumptions, estimates, and measurements, all of which are subject to considerable uncertainty. In some cases, models have been used based on experiences from other contaminated areas elsewhere in the world, which are subject to climatic and other conditions that diverge from those in the Thule area. The calculated doses are thus associated with considerable uncertainty, which must be taken into account when the results are used for comparison and when the risks of staying in the Thule area are assessed. It has therefore been chosen to provide the assessed radiation doses in the form of indicative orders of magnitude, which are applicable to everyone who might stay in the area, across various age groups. If the estimated doses in this report are combined with the National Institute of Radiation Protection's recommended reference level for contamination as a result of the Thule Accident of 1 mSv/year, the assessed magnitudes of radiation doses for inhalation and ingestion as exposure pathways are many orders of magnitude below the reference level (10,000-10 million times smaller). The wound contamination exposure pathway has a magnitude of radiation dose that is smaller than the reference level by a factor of 10-1000, and it should be recalled that the

  12. Assessment of patient doses and image quality in X-ray diagnostics in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Olerud, H.M.

    1998-06-01

    Results from other industrialized countries indicate that the annual number of diagnostic procedures approaches one for every member of the population, and in many cases the individual radiation doses are higher than from any other human activity. Furthermore, the doses to patients for the same type of examination differ widely from place to place, suggesting that there is a considerable potential for dose reduction. This motivated an investigation of the diagnostic use of X-rays in Norway. The trends in the number of X-ray examinations performed annually have been studied. The patient doses (all diagnostics) and image quality (mammography and computed tomography) have been assessed for various radiological procedures. This form the basis for the assessment of total collective effective dose (CED) from X-rays in Norway, and further risk estimates. The radiological practice has then been evaluated according to the radiation protection principles of justification and optimisation. Based on the 1993 examination frequency, the total CED was assessed to 3400 manSv (0.78 mSv/inhabitant). It is estimated that this radiation burden may cause about 100 excess cancer deaths annually. The frequency of CT examination has doubled every fifth year, and did in 1993 represent 7% of the total number of examinations and 30% of the total CED. 129 refs.

  13. Only minor additional metabolic health benefits of high as opposed to moderate dose physical exercise in young, moderately overweight men

    DEFF Research Database (Denmark)

    Reichkendler, M H; Larsen, Mads Rosenkilde; Auerbach, P L

    2014-01-01

    OBJECTIVE: The dose-response effects of exercise training on insulin sensitivity, metabolic risk, and quality of life were examined. METHODS: Sixty-one healthy, sedentary (VO₂max: 35 ± 5 ml/kg/min), moderately overweight (BMI: 27.9 ± 1.8), young (age: 29 ± 6 years) men were randomized to sedentary...

  14. Addition of low-dose rosiglitazone to sulphonylurea therapy improves glycaemic control in Type 2 diabetic patients

    NARCIS (Netherlands)

    Wolffenbuttel, B H; Gomis, R; Squatrito, S; Jones, N P; Patwardhan, R N

    2000-01-01

    AIMS: This study was designed to test the efficacy and safety of low-dose rosiglitazone, a potent, insulin-sensitizing thiazolidinedione, in combination with sulphonylurea in Type 2 diabetic patients. METHODS: For the intention-to-treat analysis, 574 patients (59% male, mean age 61 years) were avail

  15. Addition of low-dose rosiglitazone to sulphonylurea therapy improves glycaemic control in Type 2 diabetic patients

    NARCIS (Netherlands)

    Wolffenbuttel, B H; Gomis, R; Squatrito, S; Jones, N P; Patwardhan, R N

    2000-01-01

    AIMS: This study was designed to test the efficacy and safety of low-dose rosiglitazone, a potent, insulin-sensitizing thiazolidinedione, in combination with sulphonylurea in Type 2 diabetic patients. METHODS: For the intention-to-treat analysis, 574 patients (59% male, mean age 61 years) were avail

  16. ACUTRI a computer code for assessing doses to the general public due to acute tritium releases

    CERN Document Server

    Yokoyama, S; Noguchi, H; Ryufuku, S; Sasaki, T

    2002-01-01

    Tritium, which is used as a fuel of a D-T burning fusion reactor, is the most important radionuclide for the safety assessment of a nuclear fusion experimental reactor such as ITER. Thus, a computer code, ACUTRI, which calculates the radiological impact of tritium released accidentally to the atmosphere, has been developed, aiming to be of use in a discussion of licensing of a fusion experimental reactor and an environmental safety evaluation method in Japan. ACUTRI calculates an individual tritium dose based on transfer models specific to tritium in the environment and ICRP dose models. In this calculation it is also possible to analyze statistically on meteorology in the same way as a conventional dose assessment method according to the meteorological guide of the Nuclear Safety Commission of Japan. A Gaussian plume model is used for calculating the atmospheric dispersion of tritium gas (HT) and/or tritiated water (HTO). The environmental pathway model in ACUTRI considers the following internal exposures: i...

  17. Benchmark dose profiles for joint-action continuous data in quantitative risk assessment.

    Science.gov (United States)

    Deutsch, Roland C; Piegorsch, Walter W

    2013-09-01

    Benchmark analysis is a widely used tool in biomedical and environmental risk assessment. Therein, estimation of minimum exposure levels, called benchmark doses (BMDs), that induce a prespecified benchmark response (BMR) is well understood for the case of an adverse response to a single stimulus. For cases where two agents are studied in tandem, however, the benchmark approach is far less developed. This paper demonstrates how the benchmark modeling paradigm can be expanded from the single-agent setting to joint-action, two-agent studies. Focus is on continuous response outcomes. Extending the single-exposure setting, representations of risk are based on a joint-action dose-response model involving both agents. Based on such a model, the concept of a benchmark profile-a two-dimensional analog of the single-dose BMD at which both agents achieve the specified BMR-is defined for use in quantitative risk characterization and assessment.

  18. Impact of acquired immunity and dose-dependent probability of illness on quantitative microbial risk assessment

    NARCIS (Netherlands)

    Havelaar, A. H.; Swart, A. N.

    2014-01-01

    Dose-response models in microbial risk assessment consider two steps in the process ultimately leading to illness: from exposure to (asymptomatic) infection, and from infection to (symptomatic) illness. Most data and theoretical approaches are available for the exposure-infection step; the infection

  19. Addition of a third field significantly increases dose to the brachial plexus for patients undergoing tangential whole-breast therapy after lumpectomy

    Energy Technology Data Exchange (ETDEWEB)

    Stanic, Sinisa; Mathai, Mathew; Mayadev, Jyoti S.; Do, Ly V.; Purdy, James A. [Department of Radiation Oncology, University of California, Davis, Sacramento, CA (United States); Chen, Allen M., E-mail: allen.chen@ucdmc.ucdavis.edu [Department of Radiation Oncology, University of California, Davis, Sacramento, CA (United States)

    2012-07-01

    Our goal was to evaluate brachial plexus (BP) dose with and without the use of supraclavicular (SCL) irradiation in patients undergoing breast-conserving therapy with whole-breast radiation therapy (RT) after lumpectomy. Using the standardized Radiation Therapy Oncology Group (RTOG)-endorsed guidelines delineation, we contoured the BP for 10 postlumpectomy breast cancer patients. The radiation dose to the whole breast was 50.4 Gy using tangential fields in 1.8-Gy fractions, followed by a conedown to the operative bed using electrons (10 Gy). The prescription dose to the SCL field was 50.4 Gy, delivered to 3-cm depth. The mean BP volume was 14.5 {+-} 1.5 cm{sup 3}. With tangential fields alone, the median mean dose to the BP was 0.57 Gy, the median maximum dose was 1.93 Gy, and the irradiated volume of the BP receiving 40, 45, and 50 Gy was 0%. When the third (SCL field) was added, the dose to the BP was significantly increased (P = .01): the median mean dose to the BP was 40.60 Gy, and the median maximum dose was 52.22 Gy. With 3-field RT, the median irradiated volume of the BP receiving 40, 45, and 50 Gy was 83.5%, 68.5%, and 24.6%, respectively. The addition of the SCL field significantly increases dose to the BP. The possibility of increasing the risk of BP morbidity should be considered in the context of clinical decision making.

  20. Addition of a third field significantly increases dose to the brachial plexus for patients undergoing tangential whole-breast therapy after lumpectomy.

    Science.gov (United States)

    Stanic, Sinisa; Mathai, Mathew; Mayadev, Jyoti S; Do, Ly V; Purdy, James A; Chen, Allen M

    2012-01-01

    Our goal was to evaluate brachial plexus (BP) dose with and without the use of supraclavicular (SCL) irradiation in patients undergoing breast-conserving therapy with whole-breast radiation therapy (RT) after lumpectomy. Using the standardized Radiation Therapy Oncology Group (RTOG)-endorsed guidelines delineation, we contoured the BP for 10 postlumpectomy breast cancer patients. The radiation dose to the whole breast was 50.4 Gy using tangential fields in 1.8-Gy fractions, followed by a conedown to the operative bed using electrons (10 Gy). The prescription dose to the SCL field was 50.4 Gy, delivered to 3-cm depth. The mean BP volume was 14.5 ± 1.5 cm(3). With tangential fields alone, the median mean dose to the BP was 0.57 Gy, the median maximum dose was 1.93 Gy, and the irradiated volume of the BP receiving 40, 45, and 50 Gy was 0%. When the third (SCL field) was added, the dose to the BP was significantly increased (P = .01): the median mean dose to the BP was 40.60 Gy, and the median maximum dose was 52.22 Gy. With 3-field RT, the median irradiated volume of the BP receiving 40, 45, and 50 Gy was 83.5%, 68.5%, and 24.6%, respectively. The addition of the SCL field significantly increases dose to the BP. The possibility of increasing the risk of BP morbidity should be considered in the context of clinical decision making.

  1. Clinical evaluation of a dose monitoring software tool based on Monte Carlo Simulation in assessment of eye lens doses for cranial CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Guberina, Nika; Suntharalingam, Saravanabavaan; Nassenstein, Kai; Forsting, Michael; Theysohn, Jens; Wetter, Axel; Ringelstein, Adrian [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)

    2016-10-15

    The aim of this study was to verify the results of a dose monitoring software tool based on Monte Carlo Simulation (MCS) in assessment of eye lens doses for cranial CT scans. In cooperation with the Federal Office for Radiation Protection (Neuherberg, Germany), phantom measurements were performed with thermoluminescence dosimeters (TLD LiF:Mg,Ti) using cranial CT protocols: (I) CT angiography; (II) unenhanced, cranial CT scans with gantry angulation at a single and (III) without gantry angulation at a dual source CT scanner. Eye lens doses calculated by the dose monitoring tool based on MCS and assessed with TLDs were compared. Eye lens doses are summarized as follows: (I) CT angiography (a) MCS 7 mSv, (b) TLD 5 mSv; (II) unenhanced, cranial CT scan with gantry angulation, (c) MCS 45 mSv, (d) TLD 5 mSv; (III) unenhanced, cranial CT scan without gantry angulation (e) MCS 38 mSv, (f) TLD 35 mSv. Intermodality comparison shows an inaccurate calculation of eye lens doses in unenhanced cranial CT protocols at the single source CT scanner due to the disregard of gantry angulation. On the contrary, the dose monitoring tool showed an accurate calculation of eye lens doses at the dual source CT scanner without gantry angulation and for CT angiography examinations. The dose monitoring software tool based on MCS gave accurate estimates of eye lens doses in cranial CT protocols. However, knowledge of protocol and software specific influences is crucial for correct assessment of eye lens doses in routine clinical use. (orig.)

  2. Development of environmental dose assessment system (EDAS) code of PC version

    Energy Technology Data Exchange (ETDEWEB)

    Taki, Mitsumasa; Kikuchi, Masamitsu; Kobayashi, Hideo; Yamaguchi, Takenori [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-05-01

    A computer code (EDAS) was developed to assess the public dose for the safety assessment to get the license of nuclear reactor operation. This code system is used for the safety analysis of public around the nuclear reactor in normal operation and severe accident. This code was revised and composed for personal computer user according to the Nuclear Safety Guidelines reflected the ICRP1990 recommendation. These guidelines are revised by Nuclear Safety Commission on March, 2001, which are 'Weather analysis guideline for the safety assessment of nuclear power reactor', 'Public dose around the facility assessment guideline corresponding to the objective value for nuclear power light water reactor' and 'Public dose assessment guideline for safety review of nuclear power light water reactor'. This code has been already opened for public user by JAERI, and English version code and user manual are also prepared. This English version code is helpful for international cooperation concerning the nuclear safety assessment with JAERI. (author)

  3. Radioactivity in food and the environment: calculations of UK radiation doses using integrated assessment methods

    Energy Technology Data Exchange (ETDEWEB)

    Camplin, W C; Brownless, G P; Round, G D; Winpenny, K; Hunt, G J [Centre for Environment, Fisheries and Aquaculture Science, CEFAS Laboratory, Lowestoft (United Kingdom)

    2002-12-01

    A new method for estimating radiation doses to UK critical groups is proposed for discussion. Amongst others, the Food Standards Agency (FSA) and the Scottish Environment Protection Agency (SEPA) undertake surveillance of UK food and the environment as a check on the effect of discharges of radioactive wastes. Discharges in gaseous and liquid form are made under authorisation by the Environment Agency and SEPA under powers in the Radioactive Substance Act. Results of surveillance by the FSA and SEPA are published in the Radioactivity in Food and the Environment (RIFE) report series. In these reports, doses to critical groups are normally estimated separately for gaseous and liquid discharge pathways. Simple summation of these doses would tend to overestimate doses actually received. Three different methods of combining the effects of both types of discharge in an integrated assessment are considered and ranked according to their ease of application, transparency, scientific rigour and presentational issues. A single integrated assessment method is then chosen for further study. Doses are calculated for surveillance data for the calendar year 2000 and compared with those from the existing RIFE method.

  4. How to assess success of treatment when using multiple doses: the case of misoprostol for medical abortion.

    Science.gov (United States)

    Seuc, Armando H; Shah, Iqbal H; Ali, Moazzam; Diaz-Olavarrieta, Claudia; Temmerman, Marleen

    2015-11-07

    The assessment of treatment success in clinical trials when multiple (repeated) doses (courses) are involved is quite common, for example, in the case of infertility treatment with assisted reproductive technology (ART), and medical abortion using misoprostol alone or in combination with mifepristone. Under these or similar circumstances, most researchers assess success using binomial proportions after a certain number of consecutive doses, and some have used survival analysis. In this paper we discuss the main problems in using binomial proportions to summarize (the overall) efficacy after two or more consecutive doses of the relevant treatment, particularly for the case of misoprostol in medical abortion studies. We later discuss why the survival analysis is best suited under these circumstances, and illustrate this by using simulated data. The formulas required for the binomial proportion and survival analysis (without and with competing risks) approaches are summarized and analytically compared. Additionally, numerical results are computed and compared between the two approaches, for several theoretical scenarios. The main conceptual limitations of the binomial proportion approach are identified and discussed, caused mainly by the presence of censoring and competing risks, and it is demonstrated how survival analysis can solve these problems. In general, the binomial proportion approach tends to underestimate the "real" success rate, and tends to overestimate the corresponding standard error. Depending on the rates of censored observations or competing events between repeated doses of the treatment, the bias of the binomial proportion approach as compared to the survival analysis approaches varies; however, the use of the binomial approach is unjustified as the survival analysis options are well known and available in multiple statistical packages. Our conclusions also apply to other situations where success is estimated after multiple (repeated) doses (courses

  5. Assessment of radiation dose in nuclear cardiovascular imaging using realistic computational models

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Tianwu [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva 4 CH-1211 (Switzerland); Lee, Choonsik [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Bolch, Wesley E. [Departments of Nuclear and Radiological and Biomedical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Zaidi, Habib, E-mail: habib.zaidi@hcuge.ch [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva 4 CH-1211 (Switzerland); Geneva Neuroscience Center, Geneva University, Geneva CH-1205 (Switzerland); Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen 9700 RB (Netherlands)

    2015-06-15

    Purpose: Nuclear cardiology plays an important role in clinical assessment and has enormous impact on the management of a variety of cardiovascular diseases. Pediatric patients at different age groups are exposed to a spectrum of radiation dose levels and associated cancer risks different from those of adults in diagnostic nuclear medicine procedures. Therefore, comprehensive radiation dosimetry evaluations for commonly used myocardial perfusion imaging (MPI) and viability radiotracers in target population (children and adults) at different age groups are highly desired. Methods: Using Monte Carlo calculations and biological effects of ionizing radiation VII model, we calculate the S-values for a number of radionuclides (Tl-201, Tc-99m, I-123, C-11, N-13, O-15, F-18, and Rb-82) and estimate the absorbed dose and effective dose for 12 MPI radiotracers in computational models including the newborn, 1-, 5-, 10-, 15-yr-old, and adult male and female computational phantoms. Results: For most organs, {sup 201}Tl produces the highest absorbed dose whereas {sup 82}Rb and {sup 15}O-water produce the lowest absorbed dose. For the newborn baby and adult patient, the effective dose of {sup 82}Rb is 48% and 77% lower than that of {sup 99m}Tc-tetrofosmin (rest), respectively. Conclusions: {sup 82}Rb results in lower effective dose in adults compared to {sup 99m}Tc-labeled tracers. However, this advantage is less apparent in children. The produced dosimetric databases for various radiotracers used in cardiovascular imaging, using new generation of computational models, can be used for risk-benefit assessment of a spectrum of patient population in clinical nuclear cardiology practice.

  6. Radiation dose assessment in a 320-detector-row CT scanner used in cardiac imaging

    Energy Technology Data Exchange (ETDEWEB)

    Goma, Carles; Ruiz, Agustin; Jornet, Nuria; Latorre, Artur; Pallerol, Rosa M.; Carrasco, Pablo; Eudaldo, Teresa; Ribas, Montserrat [Servei de Radiofisica i Radioproteccio, Hospital de la Santa Creu i Sant Pau, Sant Antoni Maria Claret 167, 08025 Barcelona (Spain)

    2011-03-15

    Purpose: In the present era of cone-beam CT scanners, the use of the standardized CTDI{sub 100} as a surrogate of the idealized CTDI is strongly discouraged and, consequently, so should be the use of the dose-length product (DLP) as an estimate of the total energy imparted to the patient. However, the DLP is still widely used as a reference quantity to normalize the effective dose for a given scan protocol mainly because the CTDI{sub 100} is an easy-to-measure quantity. The aim of this article is therefore to describe a method for radiation dose assessment in large cone-beam single axial scans, which leads to a straightforward estimation of the total energy imparted to the patient. The authors developed a method accessible to all medical physicists and easy to implement in clinical practice in an attempt to update the bridge between CT dosimetry and the estimation of the effective dose. Methods: The authors used commercially available material and a simple mathematical model. The method described herein is based on the dosimetry paradigm introduced by the AAPM Task Group 111. It consists of measuring the dose profiles at the center and the periphery of a long body phantom with a commercial solid-state detector. A weighted dose profile is then calculated from these measurements. To calculate the CT dosimetric quantities analytically, a Gaussian function was fitted to the dose profile data. Furthermore, the Gaussian model has the power to condense the z-axis information of the dose profile in two parameters: The single-scan central dose, f(0), and the width of the profile, {sigma}. To check the energy dependence of the solid-state detector, the authors compared the dose profiles to measurements made with a small volume ion chamber. To validate the overall method, the authors compared the CTDI{sub 100} calculated analytically to the measurement made with a 100 mm pencil ion chamber. Results: For the central and weighted dose profiles, the authors found a good

  7. SU-E-J-06: Additional Imaging Guidance Dose to Patient Organs Resulting From X-Ray Tubes Used in CyberKnife Image Guidance System

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, A; Ding, G [Vanderbilt University, Nashville, TN (United States)

    2015-06-15

    Purpose: The use of image-guided radiation therapy (IGRT) has become increasingly common, but the additional radiation exposure resulting from repeated image guidance procedures raises concerns. Although there are many studies reporting imaging dose from different image guidance devices, imaging dose for the CyberKnife Robotic Radiosurgery System is not available. This study provides estimated organ doses resulting from image guidance procedures on the CyberKnife system. Methods: Commercially available Monte Carlo software, PCXMC, was used to calculate average organ doses resulting from x-ray tubes used in the CyberKnife system. There are seven imaging protocols with kVp ranging from 60 – 120 kV and 15 mAs for treatment sites in the Cranium, Head and Neck, Thorax, and Abdomen. The output of each image protocol was measured at treatment isocenter. For each site and protocol, Adult body sizes ranging from anorexic to extremely obese were simulated since organ dose depends on patient size. Doses for all organs within the imaging field-of-view of each site were calculated for a single image acquisition from both of the orthogonal x-ray tubes. Results: Average organ doses were <1.0 mGy for every treatment site and imaging protocol. For a given organ, dose increases as kV increases or body size decreases. Higher doses are typically reported for skeletal components, such as the skull, ribs, or clavicles, than for softtissue organs. Typical organ doses due to a single exposure are estimated as 0.23 mGy to the brain, 0.29 mGy to the heart, 0.08 mGy to the kidneys, etc., depending on the imaging protocol and site. Conclusion: The organ doses vary with treatment site, imaging protocol and patient size. Although the organ dose from a single image acquisition resulting from two orthogonal beams is generally insignificant, the sum of repeated image acquisitions (>100) could reach 10–20 cGy for a typical treatment fraction.

  8. The use of ESR spectroscopy for the identification and dose assessment of irradiated pink shrimp (Parapenaeus longirostris) from Turkey

    Science.gov (United States)

    Aydaş, Canan; Tepe Çam, Semra; Engin, Birol; Aydın, Talat; Polat, Mustafa

    2013-03-01

    Turkish pink shrimp (Parapenaeus longirostris) samples were studied by electron spin resonance (ESR) spectroscopy for identification and dose assessment purposes. In this work, the calcified shells of shrimps were used as a sample material. Before irradiation, all shrimp shell samples exhibit one weak ESR singlet with a g-factor of 2.0047. After irradiation, all samples exhibit two asymmetric ESR signal components centered at g-values of 2.0013 and 1.9959. The dose-response curves of the samples exposed to gamma radiations were found to be described well by a single saturation exponential function. Variation of ESR signal intensity of irradiated samples at room and-20 °C temperatures with time in a long-term showed that free radicals responsible from the ESR spectrum of shrimp shells were not stable but still detectable after 87 days. Also, the kinetic behavior of signal at g=2.0013 was studied and the additive dose method was used to evaluate the dose in the product.

  9. Assessment of the occupational eye lens dose for clinical staff in interventional radiology, cardiology and neuroradiology.

    Science.gov (United States)

    Omar, Artur; Kadesjö, Nils; Palmgren, Charlotta; Marteinsdottir, Maria; Segerdahl, Tony; Fransson, Annette

    2017-03-20

    In accordance with recommendations by the International Commission on Radiological Protection, the current European Basic Safety Standards has adopted a reduced occupational eye lens dose limit of 20 mSv yr(-1). The radiation safety implications of this dose limit is of concern for clinical staff that work with relatively high dose x-ray angiography and interventional radiology. Presented in this work is a thorough assessment of the occupational eye lens dose based on clinical measurements with active personal dosimeters worn by staff during various types of procedures in interventional radiology, cardiology and neuroradiology. Results are presented in terms of the estimated equivalent eye lens dose for various medical professions. In order to compare the risk of exceeding the regulatory annual eye lens dose limit for the widely different clinical situations investigated in this work, the different medical professions were separated into categories based on their distinct work pattern: staff that work (a) regularly beside the patient, (b) in proximity to the patient and (c) typically at a distance from the patient. The results demonstrate that the risk of exceeding the annual eye lens dose limit is of concern for staff category (a), i.e. mainly the primary radiologist/cardiologist. However, the results also demonstrate that the risk can be greatly mitigated if radiation protection shields are used in the clinical routine. The results presented in this work cover a wide range of clinical situations, and can be used as a first indication of the risk of exceeding the annual eye lens dose limit for staff at other medical centres.

  10. [Dosimetric system for assessing doses received by people occupationally exposed to external sources of ionizing radiation].

    Science.gov (United States)

    Brodecki, Marcin; Domienik, Joanna U; Zmyślony, Marek

    2012-01-01

    The current system of dosimetric quantities has been defined by the International Commission on Radiological Protection (ICRP) and the International Commission on Radiation Units and Measurements (ICRU). Complexity of the system implies the physical nature of ionizing radiation, resulting from the presence of different types of radiation of different ionization capabilities, as well as the individual radiation sensitivity of biological material exposed. According to the latest recommendations, there are three types of dosimeter quantities relevant to radiation protection and radiological assessment of occupational exposure. These are the basic quantities, safety quantities and operational quantities. Dose limits for occupational exposure relate directly to the protection quantities, i.e. the equivalent dose and effective dose, while these quantities are practically unmeasurable in real measurement conditions. For this reason, in the system of dosimetric quantities directly measurable operating volumes were defined. They represent equivalents of the protection quantities that allow for a reliable assessment of equivalent and effective dose by conducting routine monitoring of occupational exposure. This paper presents the characteristics of these quantities, their relationships and importance in assessing individual effects of radiation. Also the methods for their implementation in personal and environmental dosimetry were showcased. The material contained in the article is a compendium of essential information about dosimetric quantities with reference to the contemporary requirements of the law, including the changed annual occupational exposure limit for the lens of the eye. The material is especially addressed to those responsible for dosimetry monitoring in the workplace, radiation protection inspectors and occupational health physicians.

  11. Internal dose assessment due to large area contamination: Main lessons drawn from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Andrasi, A. [KFKI Atomic Energy Research Inst., Budapest (Hungary)

    1997-03-01

    The reactor accident at Chernobyl in 1986 beside its serious and tragic consequences provided also an excellent opportunity to check, test and validate all kind of environmental models and calculation tools which were available in the emergency preparedness systems of different countries. Assessment of internal and external doses due to the accident has been carried out for the population all over Europe using different methods. Dose predictions based on environmental model calculation considering various pathways have been compared with those obtained by more direct monitoring methods. One study from Hungary and one from the TAEA is presented shortly. (orig./DG)

  12. Beyond dose assessment: using risk with full disclosure of uncertainty in public and scientific communication.

    Science.gov (United States)

    Hoffman, F Owen; Kocher, David C; Apostoaei, A Iulian

    2011-11-01

    Evaluations of radiation exposures of workers and the public traditionally focus on assessments of radiation dose, especially annual dose, without explicitly evaluating the health risk associated with those exposures, principally the risk of radiation-induced cancer. When dose is the endpoint of an assessment, opportunities to communicate the significance of exposures are limited to comparisons with dose criteria in regulations, doses due to natural background or medical x-rays, and doses above which a statistically significant increase of disease has been observed in epidemiologic studies. Risk assessment generally addresses the chance (probability) that specific diseases might be induced by past, present, or future exposure. The risk of cancer per unit dose will vary depending on gender, age, exposure type (acute or chronic), and radiation type. It is not uncommon to find that two individuals with the same effective dose will have substantially different risks. Risk assessment has shown, for example, that: (a) medical exposures to computed tomography scans have become a leading source of future risk to the general population, and that the risk would be increased above recently published estimates if the incidence of skin cancer and the increased risk from exposure to x-rays compared with high-energy photons were taken into account; (b) indoor radon is a significant contributor to the baseline risk of lung cancer, particularly among people who have never smoked; and (c) members of the public who were exposed in childhood to I in fallout from atmospheric nuclear weapons tests and were diagnosed with thyroid cancer later in life would frequently meet criteria established for federal compensation of cancers experienced by energy workers and military participants at atmospheric weapons tests. Risk estimation also enables comparisons of impacts of exposures to radiation and chemical carcinogens and other hazards to life and health. Communication of risk with

  13. Assessing Leg length Discrepancy Using a Biplane Low Dose Imaging System. A Comparative Diagnostic Study

    DEFF Research Database (Denmark)

    Jensen, Janni; Mussmann, Bo Redder; Torfing, Trine

    study was to evaluate the diagnostic accuracy of leg length (LL) measurements performed on low dose pre-view images acquired using a new bi-planar imaging system. The administered radiation dose from the pre-view image is approximately 20,17μGycm2 vs. 2670μGycm2 when acquiring the diagnostic image......Purpose. The etiology of leg length discrepancy (LLD) is multiple and children with LLD often undergo repetitive radiographic assessment and monitoring, stressing the need for a reliable measuring tool whilst administering as little radiation to the child as possible. The aim of this retrospective...

  14. Combinations of cocaine with other dopamine uptake inhibitors: assessment of additivity.

    Science.gov (United States)

    Tanda, Gianluigi; Newman, Amy Hauck; Ebbs, Aaron L; Tronci, Valeria; Green, Jennifer L; Tallarida, Ronald J; Katz, Jonathan L

    2009-09-01

    Drugs that inhibit dopamine (DA) reuptake through actions at the dopamine transporter (DAT) have been proposed as candidates for development as pharmacotherapies for cocaine abuse. Accordingly, it is important to understand the potential pharmacological interactions of cocaine with other drugs acting at the DAT. Effects of combinations of cocaine with a cocaine analog, 2beta-carbomethoxy-3beta-(4-fluorophenyl)tropane (WIN 35,428), were compared quantitatively with the combinations of cocaine with the N-butyl,4',4''-diF benztropine analog, 3-(bis(4-fluorophenyl)methoxy)-8-butyl-8-azabicyclo[3.2.1]octane (JHW 007), to determine whether their effects on DA levels in the shell of the nucleus accumbens (NAC) in mice differed. Each of the drugs alone produced dose-related elevations in NAC DA levels. In contrast to the other drugs, JHW 007 was less effective, producing maximal effects that approached 400% of control versus approximately 700% with the other drugs. In addition, the JHW 007 dose-effect curve was not as steep as those for cocaine and WIN 35,428. Combinations of cocaine with its analog, WIN 35,428, were most often greater than those predicted based on dose additivity. In contrast, combinations of cocaine with JHW 007 were most often subadditive. This outcome is consistent with recent studies suggesting that structurally divergent DA uptake inhibitors bind to different domains of the DAT, which can result in different DAT conformations. The conformational changes occurring with JHW 007 binding may result in functional outcomes that alter its abuse liability and its effects in combination with cocaine.

  15. Human Health Risk Assessment: A case study application of principles in dose response assessment

    Science.gov (United States)

    This case study application workshop will build on fundamental concepts and techniques in risk assessment presented and archived at previous TRAC meeting workshops. Practical examples from publicly available, peer reviewed risk assessments will be used as teaching aids. Course ...

  16. Information on Hydrologic Conceptual Models, Parameters, Uncertainty Analysis, and Data Sources for Dose Assessments at Decommissioning Sites

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Philip D.; Gee, Glendon W.; Nicholson, Thomas J.

    2000-02-28

    This report addresses issues related to the analysis of uncertainty in dose assessments conducted as part of decommissioning analyses. The analysis is limited to the hydrologic aspects of the exposure pathway involving infiltration of water at the ground surface, leaching of contaminants, and transport of contaminants through the groundwater to a point of exposure. The basic conceptual models and mathematical implementations of three dose assessment codes are outlined along with the site-specific conditions under which the codes may provide inaccurate, potentially nonconservative results. In addition, the hydrologic parameters of the codes are identified and compared. A methodology for parameter uncertainty assessment is outlined that considers the potential data limitations and modeling needs of decommissioning analyses. This methodology uses generic parameter distributions based on national or regional databases, sensitivity analysis, probabilistic modeling, and Bayesian updating to incorporate site-specific information. Data sources for best-estimate parameter values and parameter uncertainty information are also reviewed. A follow-on report will illustrate the uncertainty assessment methodology using decommissioning test cases.

  17. 3D delivered dose assessment using a 4DCT-based motion model

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Weixing; Hurwitz, Martina H.; Williams, Christopher L.; Dhou, Salam; Berbeco, Ross I.; Mishra, Pankaj, E-mail: wcai@lroc.harvard.edu, E-mail: jhlewis@lroc.harvard.edu; Lewis, John H., E-mail: wcai@lroc.harvard.edu, E-mail: jhlewis@lroc.harvard.edu [Brigham and Women’s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States); Seco, Joao [Francis H. Burr Proton Therapy Center, Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2015-06-15

    reconstructed from kV and MV projections compared to the ground truth, which is clinically comparable to 4DCT (0.093%). For the second XCAT phantom that has an irregular breathing pattern, the errors are 0.81% and 1.75% for kV and MV reconstructions, both of which are better than that of 4DCT (4.01%). In the case of real patient, although it is impossible to obtain the actual delivered dose, the dose estimation is clinically reasonable and demonstrates differences between 4DCT and MV reconstruction-based dose estimates. Conclusions: With the availability of kV or MV projection images, the proposed approach is able to assess delivered doses for all respiratory phases during treatment. Compared to the planning dose based on 4DCT, the dose estimation using reconstructed 3D fluoroscopic images was as good as 4DCT for regular respiratory pattern and was a better dose estimation for the irregular respiratory pattern.

  18. Dose assessment for ingestion of a 330 kilo-becquerel {sup 60}Co hot particle

    Energy Technology Data Exchange (ETDEWEB)

    Whillans, D.W.; Chase, W.J.; Wolodarsky, W.H. [Health Physics Department, Ontario Power Generation, Whitby, Ontario, L1 N 9E3 (Canada)

    2007-07-01

    On leaving the irradiated fuel bay at Pickering A nuclear power station, a worker triggered a whole body monitor alarm with activity in or on his head, and despite careful decontamination techniques he subsequently swallowed a hot particle. Over the next 3 d, the radioactivity was tracked through the body. It was then excreted in a single faecal sample and recovered for physical and radiochemical analysis. This analysis demonstrated that the particle contained 330 kBq of {sup 60}Co and only traces of other radioactivity. Its dimensions were {approx}50-130 {mu}m and its composition was consistent with that of Stellite 6. A dose assessment was carried out taking into account the residence time of the particle in the mouth and its transit through the body. The estimated committed effective dose was 1.4 mSv, and the equivalent dose to the maximally exposed 1 cm{sup 2} of skin, 81 mSv. (authors)

  19. Shutdown dose rate assessment with the Advanced D1S method: Development, applications and validation

    Energy Technology Data Exchange (ETDEWEB)

    Villari, R., E-mail: rosaria.villari@enea.it [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Fischer, U. [Karlsruhe Institute of Technology KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Moro, F. [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Pereslavtsev, P. [Karlsruhe Institute of Technology KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Petrizzi, L. [European Commission, DG Research and Innovation K5, CDMA 00/030, B-1049 Brussels (Belgium); Podda, S. [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Serikov, A. [Karlsruhe Institute of Technology KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2014-10-15

    Highlights: Development of Advanced-D1S for shutdown dose rate calculations; Recent applications of the tool to tokamaks; Summary of the results of benchmarking with measurements and R2S calculations; Limitations and further development. Abstract: The present paper addresses the recent developments and applications of Advanced-D1S to the calculations of shutdown dose rate in tokamak devices. Results of benchmarking with measurements and Rigorous 2-Step (R2S) calculations are summarized and discussed as well as limitations and further developments. The outcomes confirm the essential role of the Advanced-D1S methodology and the evidence for its complementary use with the R2Smesh approach for the reliable assessment of shutdown dose rates and related statistical uncertainties in present and future fusion devices.

  20. Lack-of-fit tests for assessing mean structures for continuous dose-response data

    DEFF Research Database (Denmark)

    Martinussen, Torben

    2011-01-01

    We review a range of lack-of-fit tests suitable for assessing the appropriateness of the mean function in dose-response models. The review encompasses both well-known tests and new tests based on recent developments in statistics, which we have extended to the dose-response case. We argue...... that the classical methods are inadequate in certain situations, where the new tests may be applied. Power comparisons are carried out by means of extensive simulation studies, covering both designs with and without replicates at small and large sample sizes. Three datasets from dose-response applications illustrate...... differences and similarities between the tests. The results suggest that the new tests perform better and exhibit a wider applicability....

  1. A preliminary assessment of potential doses to man from radioactive waste dumped in the Arctic sea

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, S.P. [Risoe National Lab., Roskilde (Denmark); Iosjpe, M.; Strand, P. [Statens Straalevern, Oesteraas (Norway)

    1995-11-01

    This report describes a preliminary radiological assessment of collective doses to the world population from radioactive material dumped in the Kara and Barents Seas in the period 1961-1991. Information on the dumped waste and the rates of release of radionuclides have been available from Russian sources and from the International Atomic Energy Agency. A box model has been used to simulate the dispersion of radionuclides in the marine environment and to calculate the contamination of seafood and the subsequent radiation doses to man. Two release scenarios have been adopted. The worst-case release scenario, which ignores the presence of barriers between spent nuclear fuel and seawater, is estimated to give rise to about 10 mansievert calculated to 1000 years from the time of release. A more realistic release scenario is estimated to cause about 3 mansieverts. In both cases exposure from the radionuclide {sup 137}Cs is found to dominate the doses. 19 refs., 56 figs., 8 tabs.

  2. A preliminary assessment of potential doses to man from radioactive waste dumped in the Arctic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, S.P. [Forskningscente Risoe, Roskilde (Denmark); Iosjpe, M.; Strand, P. [Norwegian Radiation Protection Authority, Oesteraas (Norway)

    1995-09-01

    This report describes a preliminary radiological assessment of collective doses to the world population from radioactive material dumped in the Barents and Kara Seas in the period 1961-1991. Information on the dumped waste and the rates of release of radionuclides have been available from Russian sources and from the International Atomic Energy Agency. A box model has been used to simulate the dispersion of radionuclides in the marine environment and to calculate the contamination of seafood and the subsequent radiation doses to man. Two release scenarios have been adopted. The worst-case release scenario which ignores the presence of barriers between spent nuclear fuel and seawater is estimated to give rise to about 10 mansieverts calculated to 1000 years from the time of release. A more realistic release scenario is estimated to cause about 3 mansieverts. In both cases exposure from the radionuclide {sup 137}Cs is found to dominate the doses. (au) 8 tabs., 56 ills., 19 refs.

  3. Radiation therapy for stage IIA and IIB testicular seminoma: peripheral dose calculations and risk assessments

    Science.gov (United States)

    Mazonakis, Michalis; Berris, Theocharris; Lyraraki, Efrossyni; Damilakis, John

    2015-03-01

    This study was conducted to calculate the peripheral dose to critical structures and assess the radiation risks from modern radiotherapy for stage IIA/IIB testicular seminoma. A Monte Carlo code was used for treatment simulation on a computational phantom representing an average adult. The initial treatment phase involved anteroposterior and posteroanaterior modified dog-leg fields exposing para-aortic and ipsilateral iliac lymph nodes followed by a cone-down phase for nodal mass irradiation. Peripheral doses were calculated using different modified dog-leg field dimensions and an extended conventional dog-leg portal. The risk models of the BEIR-VII report and ICRP-103 were combined with dosimetric calculations to estimate the probability of developing stochastic effects. Radiotherapy for stage IIA seminoma with a target dose of 30 Gy resulted in a range of 23.0-603.7 mGy to non-targeted peripheral tissues and organs. The corresponding range for treatment of stage IIB disease to a cumulative dose of 36 Gy was 24.2-633.9 mGy. A dose variation of less than 13% was found by altering the field dimensions. Radiotherapy with the conventional instead of the modern modified dog-leg field increased the peripheral dose up to 8.2 times. The calculated heart doses of 589.0-632.9 mGy may increase the risk for developing cardiovascular diseases whereas the testicular dose of more than 231.9 mGy may lead to a temporary infertility. The probability of birth abnormalities in the offspring of cancer survivors was below 0.13% which is much lower than the spontaneous mutation rate. Abdominoplevic irradiation may increase the lifetime intrinsic risk for the induction of secondary malignancies by 0.6-3.9% depending upon the site of interest, patient’s age and tumor dose. Radiotherapy for stage IIA/IIB seminoma with restricted fields and low doses is associated with an increased morbidity. These data may allow the definition of a risk-adapted follow-up scheme for long

  4. Actual versus prescribed timing of lovastatin doses assessed by electronic compliance monitoring.

    Science.gov (United States)

    Kruse, W; Nikolaus, T; Rampmaier, J; Weber, E; Schlierf, G

    1993-01-01

    The objective of the study was to compare compliance with and the hypocholesterolaemic effect of lovastatin given once daily as a morning or an evening dose. Twenty-four out-patients with familial hypercholesterolaemia were randomly assigned to receive placebo first, then lovastatin 20 mg, to be taken once daily for 4 weeks, either with the breakfast or evening meal, in a single-blind fashion. Drug compliance was assessed by pill counts and continuous electronic monitoring. Two compliance parameters were evaluated, consumption, defined as percentage of prescribed doses taken, and time compliance, the percentage of total dosing events recorded within defined intervals (6.00-10.00 h, and 17.00-21.00 h), for the morning and evening regimes. Both regimes satisfactorily reduced the total and LDL-cholesterol concentrations, and there was no significant difference in the extent of the reductions. Pill counts overestimated compliance, as revealed by the monitoring method. The times of actual consumption of doses by the patients often differed from that prescribed, predominantly in patients who were told to take the evening dose. Partial time compliance may have confounded the efficacy of the drugs. Electronic compliance monitoring appears to be particularly useful in chronopharmacological studies.

  5. Internal dose assessment data management system for a large population of Pu workers

    Energy Technology Data Exchange (ETDEWEB)

    Bertelli, L.; Miller, G.; Little, T.; Guilmette, R.A. [Los Alamos National Laboratory, MS G761, RP-2, Los Alamos, NM 87545 (United States); Glasser, S.M. [LogiCreativity, Santa Fe, NM (United States)

    2007-07-01

    This paper describes the design and implementation of the Los Alamos National Laboratory (LANL) dose assessment (DA) data system. Dose calculations for the most important radionuclides at LANL, namely plutonium, americium, uranium and tritium, are performed through the Microsoft Access DA database. DA includes specially developed forms and macros that perform a variety of tasks, such as retrieving bioassay data, launching the FORTRAN internal dosimetry applications and displaying dose results in the form of text summaries and plots. The DA software involves the following major processes: (1) downloading of bioassay data from a remote data source, (2) editing local and remote databases, (3) setting up and carrying out internal dose calculations using the UF code or the ID code, (3) importing results of the dose calculations into local results databases, (4) producing a secondary database of 'official results' and (5) automatically creating and e-mailing reports. The software also provides summary status and reports of the pending DAs, which are useful for managing the cases in process. (authors)

  6. Realistic retrospective dose assessments to members of the public around Spanish nuclear facilities.

    Science.gov (United States)

    Jiménez, M A; Martín-Valdepeñas, J M; García-Talavera, M; Martín-Matarranz, J L; Salas, M R; Serrano, J I; Ramos, L M

    2011-11-01

    In the frame of an epidemiological study carried out in the influence areas around the Spanish nuclear facilities (ISCIII-CSN, 2009. Epidemiological Study of The Possible Effect of Ionizing Radiations Deriving from The Operation of Spanish Nuclear Fuel Cycle Facilities on The Health of The Population Living in Their Vicinity. Final report December 2009. Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Consejo de Seguridad Nuclear. Madrid. Available from: http://www.csn.es/images/stories/actualidad_datos/especiales/epidemiologico/epidemiological_study.pdf), annual effective doses to public have been assessed by the Spanish Nuclear Safety Council (CSN) for over 45 years using a retrospective realistic-dose methodology. These values are compared with data from natural radiation exposure. For the affected population, natural radiation effective doses are in average 2300 times higher than effective doses due to the operation of nuclear installations (nuclear power stations and fuel cycle facilities). When considering the impact on the whole Spanish population, effective doses attributable to nuclear facilities represent in average 3.5×10(-5)mSv/y, in contrast to 1.6mSv/y from natural radiation or 1.3mSv/y from medical exposures.

  7. Benchmark dose profiles for joint-action quantal data in quantitative risk assessment.

    Science.gov (United States)

    Deutsch, Roland C; Piegorsch, Walter W

    2012-12-01

    Benchmark analysis is a widely used tool in public health risk analysis. Therein, estimation of minimum exposure levels, called Benchmark Doses (BMDs), that induce a prespecified Benchmark Response (BMR) is well understood for the case of an adverse response to a single stimulus. For cases where two agents are studied in tandem, however, the benchmark approach is far less developed. This article demonstrates how the benchmark modeling paradigm can be expanded from the single-dose setting to joint-action, two-agent studies. Focus is on response outcomes expressed as proportions. Extending the single-exposure setting, representations of risk are based on a joint-action dose-response model involving both agents. Based on such a model, the concept of a benchmark profile (BMP) - a two-dimensional analog of the single-dose BMD at which both agents achieve the specified BMR - is defined for use in quantitative risk characterization and assessment. The resulting, joint, low-dose guidelines can improve public health planning and risk regulation when dealing with low-level exposures to combinations of hazardous agents.

  8. Biosphere Modeling for the Dose Assessment of a HLW Repository: Development of ACBIO

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youn Myoung; Hwang, Yong Soo; Kang, Chul Hyung

    2006-01-15

    For the purpose of evaluating a dose rate to an individual due to a long-term release of nuclides from a HLW repository, a biosphere assessment model and an implemented code, ACBIO, based on the BIOMASS methodology have been developed by utilizing AMBER, a general compartment modeling tool. To demonstrate its practicability and usability as well as to observe the sensitivity of the compartment scheme, the concentration, the activity in the compartments as well as the annual flux between the compartments at their peak values, were calculated and investigated. For each case when changing the structure of the compartments and GBIs as well as varying selected input Kd values, all of which seem very important among the others, the dose rate per nuclide release rate is calculated separately and analyzed. From the maximum dose rates, the flux to dose conversion factors for each nuclide were derived, which are used for converting the nuclide release rate appearing from the geosphere through various GBIs to dose rates (Sv/y) for an individual in a critical group. It has also been observed that the compartment scheme, the identification of a possible exposure group and the GBIs could all be highly sensitive to the final consequences in a biosphere modeling.

  9. Assessment of CpTi Surface Properties after Nitrogen Ion Implantation with Various Doses and Energies

    Science.gov (United States)

    Fulazzaky, Mohamad Ali; Ali, Nurdin; Samekto, Haryanti; Ghazali, Mohd Imran

    2012-11-01

    Nitrogen ion implantation is one of the surface modification techniques used for increasing corrosion resistance of commercially pure titanium (CpTi). The nitrogen ion implanted CpTi in various doses markedly changes the corrosion resistance. Still the effect of nitrogen ion implantation on the CpTi at different energies needs to be verified. This study uses different methods to assess the CpTi surface properties after nitrogen ion implantation in various doses and energy. Surface hardness of the CpTi increases with an increase of the dose and decreases with an increase of the energy. The precipitation of the TiN increases with an increase of the nitrogen dose, and no formation of the Ti2N phase clearly appears. Corrosion resistance of the CpTi specimens can be upgraded to some extent after their surfaces are modified, implanting nitrogen ions at 100 keV by increasing dose. The optimum surface properties of the implanted CpTi are analyzed to contribute to materials science technology.

  10. Hazard identification and characterisation, and dose response assessment of spore forming pathogens in cooked chilled food containing vegetables

    NARCIS (Netherlands)

    Leusden FM van; MGB

    2001-01-01

    A hazard identification and characterisation, including a preliminary dose response assessment, of sporeforming pathogens in cooked chilled food containing vegetables was performed according to the structure and principles for a quantitative microbiological risk assessment as described by the Codex

  11. Multiple Methods for Assessing the Dose to Skin Exposed to Radioactive Contamination.

    Science.gov (United States)

    Dubeau, J; Heinmiller, B E; Corrigan, M

    2017-04-28

    There is the possibility for a worker at a nuclear installation, such as a nuclear power reactor, a fuel production facility or a medical facility, to come in contact with radioactive contaminants. When such an event occurs, the first order of business is to care for the worker by promptly initiating a decontamination process. Usually, the radiation protection personnel performs a G-M pancake probe measurement of the contamination in situ and collects part or all of the radioactive contamination for further laboratory analysis. The health physicist on duty must then perform, using the available information, a skin dose assessment that will go into the worker's permanent dose record. The contamination situations are often complex and the dose assessment can be laborious. This article compares five dose assessment methods that involve analysis, new technologies and new software. The five methods are applied to 13 actual contamination incidents consisting of direct skin contact, contamination on clothing and contamination on clothing in the presence of an air gap between the clothing and the skin. This work shows that, for the cases studied, the methods provided dose estimates that were usually within 12% (1σ) of each other, for those cases where absolute activity information for every radionuclide was available. One method, which relies simply on a G-M pancake probe measurement, appeared to be particularly useful in situations where a contamination sample could not be recovered for laboratory analysis. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Biodosimetry for dose assessment of partial-body exposure: a methodological improvement

    Directory of Open Access Journals (Sweden)

    Thiago Salazar Fernandes

    2008-12-01

    Full Text Available This study has explored the possibility of combining culture times with extending the duration for which Colcemid is present in cell culture in order to obtain better dose estimations following partial-body exposures. Irradiated and unirradiated blood was mixed to simulate a partial-exposure. Dicentric frequencies and resultant dose estimations were compared from 48 and 72 h cultures with Colcemid added at the beginning, after 24 h or for the final 3 h. The frequencies of dicentrics in first division cells increased with the cell culture time, providing better dose estimations. Unwanted excessive contraction of chromosomes caused by prolonged contact with Colcemid was measured and ways to avoid this are discussed. It is suggested that the combination of a lower than usual concentration of this drug combined with its earlier addition and longer culture time may provide metaphases better suited for interpreting partial-body exposures.Este trabalho avaliou a estimativa da dose de radiação simulando uma exposição parcial do corpo através da irradiação in vitro de amostras de sangue misturadas com amostras não irradiadas. Foi observado que o prolongamento do tempo de cultura permite que a real fração de linfócitos em M1 contendo aberrações cromossômicas seja detectada, propiciando melhores estimativas de dose, sem a necessidade de correções matemáticas.

  13. Dose Assessment using Chromosome Aberration Analyses in Human Peripheral Blood Lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Tae Ho; Kim, Jin-Hong; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The healthy five donors were recruited to establish the dose-response calibration curve for chromosomal aberrations by ionizing radiation exposure. Our cytogenetic results revealed that the mean frequency of chromosome aberration increased with increasing radiation dose. In this study, dicentric assay and CBMN assay were compared considering the sensitivity and accuracy of dose estimation. Therefore, these chromosome aberration analyses will be the foundation for biological dosimetric analysis with additional research methods such as translocation and PCC assay. The conventional analysis of dicentric chromosomes in HPBL was suggested by Bender and Gooch in 1962. This assay has been for many years, the golden standard and the most specific method for ionizing radiation damage. The dicentric assay technique in HPBL has been shown as the most sensitive biological method and reliable bio-indicator of quantifying the radiation dose. In contrast, the micronucleus assay has advantages over the dicentric assay since it is rapid and requires less specialized expertise, and accordingly it can be applied to monitor a big population. The cytokinesis-block micronucleus (CBMN) assay is a suitable method for micronuceli measurement in cultured human as well as mammalian cells. The aim of our study was to establish the dose response curve of radiation-induced chromosome aberrations in HPBL by analyzing the frequency of dicentrics and micronuclei.

  14. Cancer risk assessment: Optimizing human health through linear dose-response models.

    Science.gov (United States)

    Calabrese, Edward J; Shamoun, Dima Yazji; Hanekamp, Jaap C

    2015-07-01

    This paper proposes that generic cancer risk assessments be based on the integration of the Linear Non-Threshold (LNT) and hormetic dose-responses since optimal hormetic beneficial responses are estimated to occur at the dose associated with a 10(-4) risk level based on the use of a LNT model as applied to animal cancer studies. The adoption of the 10(-4) risk estimate provides a theoretical and practical integration of two competing risk assessment models whose predictions cannot be validated in human population studies or with standard chronic animal bioassay data. This model-integration reveals both substantial protection of the population from cancer effects (i.e. functional utility of the LNT model) while offering the possibility of significant reductions in cancer incidence should the hormetic dose-response model predictions be correct. The dose yielding the 10(-4) cancer risk therefore yields the optimized toxicologically based "regulatory sweet spot". Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Dose assessment for inhalation intakes in complex, energetic environments: experience from the US Capstone study.

    Science.gov (United States)

    Guilmette, Raymond A; Parkhurst, Mary Ann

    2007-01-01

    Because of the lack of existing information needed to evaluate the risks from inhalation exposures to depleted uranium (DU) aerosols of US soldiers during the 1991 Persian Gulf War, the US Department of Defense funded an experimental study to measure the characteristics of DU aerosols created when Abrams tanks and Bradley fighting vehicles are struck with large-caliber DU penetrators, and a dose and risk assessment for individuals present in such vehicles. This paper describes some of the difficulties experienced in dose assessment modelling of the very complex DU aerosols created in the Capstone studies, e.g. high concentrations, heterogeneous aerosol properties, non-lognormal particle size distributions, triphasic in vitro dissolution and rapid time-varying functions of both DU air concentration and particle size. The approaches used to solve these problems along with example results are presented.

  16. Integrity assessment of pipelines - additional remarks; Avaliacao da integridade de dutos - observacoes adicionais

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Luis F.C. [PETROBRAS S.A., Salvador, BA (Brazil). Unidade de Negocios. Exploracao e Producao

    2005-07-01

    Integrity assessment of pipelines is part of a process that aims to enhance the operating safety of pipelines. During this task, questions related to the interpretation of inspection reports and the way of regarding the impact of several parameters on the pipeline integrity normally come up. In order to satisfactorily answer such questions, the integrity assessment team must be able to suitably approach different subjects such as corrosion control and monitoring, assessment of metal loss and geometric anomalies, and third party activities. This paper presents additional remarks on some of these questions based on the integrity assessment of almost fifty pipelines that has been done at PETROBRAS/E and P Bahia over the past eight years. (author)

  17. Naturally occurring radioactivity in some Swedish concretes and their constituents - Assessment by using I-index and dose-model.

    Science.gov (United States)

    Döse, M; Silfwerbrand, J; Jelinek, C; Trägårdh, J; Isaksson, M

    2016-05-01

    The reference level for effective dose due to gamma radiation from building materials and construction products used for dwellings is set to 1 mSv per year (EC, 1996, 1999), (CE, 2014). Given the specific conditions presented by the EC in report 112 (1999) considering building and construction materials, an I-index of 1 may generate an effective dose of 1 mSv per year. This paper presents a comparison of the activity concentrations of (4)(0)K, (226)Ra and (232)Th of aggregates and when these aggregates constitute a part of concrete. The activity concentration assessment tool for building and construction materials, the I-index, introduced by the EC in 1996, is used in the comparison. A comparison of the I-indices values are also made with a recently presented dose model by Hoffman (2014), where density variations of the construction material and thickness of the construction walls within the building are considered. There was a ∼16-19% lower activity index in concretes than in the corresponding aggregates. The model by Hoffman further implies that the differences between the I-indices of aggregates and the concretes' final effective doses are even larger. The difference is due, mainly to a dilution effect of the added cement with low levels of natural radioisotopes, but also to a different and slightly higher subtracted background value (terrestrial value) used in the modeled calculation of the revised I-index by Hoffman (2014). Only very minimal contributions to the annual dose could be related to the water and additives used, due to their very low content of radionuclides reported.

  18. Assessment of The Dose-Response Relationship of Radiation-Induced Bystander Effect in Two Cell Lines Exposed to High Doses of Ionizing Radiation (6 and 8 Gy).

    Science.gov (United States)

    Bahreyni Toossi, Mohammad Taghi; Khademi, Sara; Azimian, Hosein; Mohebbi, Shokoufeh; Soleymanifard, Shokouhozaman

    2017-10-01

    The dose-response relationship of radiation-induced bystander effect (RIBE) is controversial at high dose levels. The aim of the present study is to assess RIBE at high dose levels by examination of different endpoints. This experimental study used the medium transfer technique to induce RIBE. The cells were divided into two main groups: QU-DB cells which received medium from autologous irradiated cells and MRC5 cells which received medium from irradiated QU-DB cells. Colony, MTT, and micronucleus assays were performed to quantify bystander responses. The medium was diluted and transferred to bystander cells to investigate whether medium dilution could revive the RIBE response that disappeared at a high dose. The RIBE level in QU-DB bystander cells increased in the dose range of 0.5 to 4 Gy, but decreased at 6 and 8 Gy. The Micronucleated cells per 1000 binucleated cells (MNBN) frequency of QU-DB bystander cells which received the most diluted medium from 6 and 8 Gy QU-DB irradiated cells reached the maximum level compared to the MNBN frequency of the cells that received complete medium (Pbystander cells. This finding confirmed that a negative feedback mechanism was responsible for the decrease in RIBE response at high doses. Decrease of RIBE at high doses might be used to predict that in radiosurgery, brachytherapy and grid therapy, in which high dose per fraction is applied, normal tissue damage owing to RIBE may decrease.

  19. Skin Dose Assessment Methodology for Military Personnel at McMurdo Station, Antarctica (1962-1979)

    Science.gov (United States)

    2014-06-01

    Regulatory Commission, Rockville, MD. May 20. WHO (World Health Organization), 2005. Health Effects of the Chernobyl Accident and Special Health Care...Programmes, Report of the UN Chernobyl Forum Expert Group “ Health ” (EGH), World Health Organization, Geneva. August 31. 18 This page intentionally...McMurdo Station Radiation Dose Assessment Integrated Project Team For: Assistant Secretary of Defense for Health Affairs and Deputy Assistant

  20. Pilot website to support international collaboration for dose assessments in a radiation emergency

    Energy Technology Data Exchange (ETDEWEB)

    Livingston, G.K., E-mail: Gordon.Livingston@orise.orau.gov [Oak Ridge Associated Universities, REAC/TS, Radiation Emergency Medicine (REM), P.O. Box 117, Oak Ridge, TN 37831 (United States); Wilkins, R.C., E-mail: Ruth.Wilkins@hc-sc.gc.ca [Health Canada, Consumer and Clinical Radiation Protection Bureau, Ottawa, ON K1A 1C1 (Canada); Ainsbury, E.A., E-mail: liz.ainsbury@hpa.org.uk [Health Protection Agency, Radiation Protection Division, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom)

    2011-09-15

    Nuclear terrorism has emerged as a significant threat which could require timely medical interventions to reduce potential radiation casualties. Early dose assessments are critical since optimal care depends on knowing a victim's radiation dose. The dicentric chromosome aberration assay is considered the 'gold standard' to estimate the radiation dose because the yield of dicentrics correlates positively with the absorbed dose. Dicentrics have a low background frequency, are independent of age and gender and are relatively easy to identify. This diagnostic test for radiation exposure, however, is labor intensive and any single or small group of laboratories could easily be overwhelmed by a mass casualty event. One solution to this potential problem is to link the global WHO BioDoseNet members via the Internet so multiple laboratories could work cooperatively to screen specimens for dicentric chromosomes and generate timely dose estimates. Inter-laboratory comparison studies have shown that analysis of electronic chromosome images viewed on the computer monitor produces scoring accuracy equivalent to viewing live images in the microscope. This functional equivalence was demonstrated during a comparative study involving five laboratories constructing {sup 60}Co gamma ray calibration curves and was further confirmed when comparing results of blind dose estimates submitted by each laboratory. It has been further validated in two recent WHO BioDoseNet trial exercises where 20 metaphase images were shared by e-mail and 50 images were shared on a test website created for this purpose. The Internet-based exercise demonstrated a high level of concordance among 20 expert scorers who evaluated the same 50 metaphase spreads selected to exhibit no, low, moderate and severe radiation damage. Nineteen of 20 scorers produced dicentric equivalent counts within the 95% confidence limits of the mean. The Chi-squared test showed strong evidence of homogeneity in the data

  1. An Analysis Of Tensile Test Results to Assess the Innovation Risk for an Additive Manufacturing Technology

    Directory of Open Access Journals (Sweden)

    Adamczak Stanisław

    2015-03-01

    Full Text Available The aim of this study was to assess the innovation risk for an additive manufacturing process. The analysis was based on the results of static tensile tests obtained for specimens made of photocured resin. The assessment involved analyzing the measurement uncertainty by applying the FMEA method. The structure of the causes and effects of the discrepancies was illustrated using the Ishikawa diagram. The risk priority numbers were calculated. The uncertainty of the tensile test measurement was determined for three printing orientations. The results suggest that the material used to fabricate the tensile specimens shows clear anisotropy of the properties in relation to the printing direction.

  2. Assessment of the Low Alloy Cast Steel Inoculation Effects with Chosen Additives

    Directory of Open Access Journals (Sweden)

    D. Bartocha

    2012-04-01

    Full Text Available Structure, and thus the mechanical properties of steel are primarily a function of chemical composition and the solidification process which can be influenced by the application of the inoculation treatment. This effect depends on the modifier used. The article presents the results of studies designed to assess the effects of structural low alloy steel inoculation by selected modifying additives. The study was performed on nine casts modeled with different inoculants, assessment of the procedure impact was based on the macrostructure of made castings. The ratio of surface area equivalent to the axial zone of the crystals and columnar crystals zone was adopted as a measure of the inoculation effect.

  3. The combination of trastuzumab and pertuzumab administered at approved doses may delay development of trastuzumab resistance by additively enhancing antibody-dependent cell-mediated cytotoxicity.

    Science.gov (United States)

    Tóth, Gábor; Szöőr, Árpád; Simon, László; Yarden, Yosef; Szöllősi, János; Vereb, György

    2016-10-01

    Although the recently concluded CLEOPATRA trial showed clinical benefits of combining trastuzumab and pertuzumab for treating HER2-positive metastatic breast cancer, trastuzumab monotherapy is still the mainstay in adjuvant settings. Since trastuzumab resistance occurs in over half of these cancers, we examined the mechanisms by which treatment of intrinsically trastuzumab-resistant and -sensitive tumors can benefit from the combination of these antibodies. F(ab')2 of both trastuzumab and pertuzumab were generated and validated in order to separately analyze antibody-dependent cell-mediated cytotoxicity (ADCC)-based and direct biological effects of the antibodies. Compared to monotherapy, combination of the two antibodies at clinically permitted doses enhanced the recruitment of natural killer cells responsible for ADCC, and significantly delayed the outgrowth of xenografts from intrinsically trastuzumab-resistant JIMT-1 cells. Antibody dose-response curves of in vitro ADCC showed that antibody-mediated killing can be saturated, and the two antibodies exert an additive effect at sub-saturation doses. Thus, the additive effect in vivo indicates that therapeutic tissue levels likely do not saturate ADCC. Additionally, isobole studies with the in vitro trastuzumab-sensitive BT-474 cells showed that the direct biological effect of combined treatment is additive, and surpasses the maximum effect of either monotherapy. Our results suggest the combined therapy is expected to give results that are superior to monotherapy, whatever the type of HER2-positive tumor may be. The combination of both antibodies at maximum clinically approved doses should thus be administered to patients to recruit maximum ADCC and cause maximum direct biological growth inhibition.

  4. Additional human exposure information for gasoline substance risk assessment (period 2002-2007)

    Energy Technology Data Exchange (ETDEWEB)

    Bomer, R.; Carter, M.; Dmytrasz, B.; Mulari, M.; Pizzella, G.; Roth, S.; Van de Sandt, P.

    2009-06-15

    This report provides an update on human exposure information for gasoline-related activities for which previous assessments had suggested that exposure was either elevated or highly variable or available data were considered out-of-date. In addition data are presented for several activities for which no information had been available previously. The occupational exposures activities described in this report include railcar loading, refinery maintenance, laboratory operations, aviation gasoline refuelling, gasoline pump maintenance and repair, gasoline pump calibration, and the operation of gasoline-powered gardening equipment. In addition, general public exposure levels are described, particularly relating to residency near service stations.

  5. Probabilistic assessment of the influence of lake properties in long-term radiation doses to humans.

    Science.gov (United States)

    Pohjola, Jari; Turunen, Jari; Lipping, Tarmo; Ikonen, Ari T K

    2016-11-01

    The assessment processes concerning the safety of nuclear waste repositories include the modelling of radionuclide transport in biosphere and the evaluation of the doses to the most affected humans. In this paper, a scenario, in which a contaminated lake is the water source for drinking water, irrigation water and watering of livestock, is presented. The objective of the paper is to probabilistically study the influence of lake properties as parameters in the assessment scenario. The properties of the lake are a result of previously conducted probabilistic studies, where the land uplift of the terrain surrounding the repositories and the formation of water bodies were studied in a 10,000-year time span using Monte Carlo simulation. The lake is formed at 3000 years from present day and the changing properties of the lake have been used in the study. The studied radionuclides (36)Cl, (135)Cs, (129)I, (237)Np, (90)Sr, (99)Tc and (238)U enter the lake with a rate of 1 Bq/year. The transport process from the lake water to humans is described and the doses (dose conversion factors) to adult humans are evaluated based on a study on average food consumption. Sensitivity analysis is used for identifying the parameters having the most influence on the outcome of the dose. Based on the results from the sensitivity analysis, the volumetric outflow rate of the lake and the volume of the lake were taken into closer consideration. The results show the influence of probabilistically derived geomorphic lake input parameters on the dose. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Non-invasive assessment of coronary artery disease with CT coronary angiography and SPECT: a novel dose-saving fast-track algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Pazhenkottil, Aju P.; Herzog, Bernhard A.; Husmann, Lars; Buechel, Ronny R.; Burger, Irene A.; Valenta, Ines; Landmesser, Ulf; Wyss, Christophe A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology (ZIHP), Zurich (Switzerland)

    2010-03-15

    To validate a new low-dose and rapid stepwise individualized algorithm for non-invasive assessment of ischemic coronary artery disease by sequential use of prospectively ECG-triggered low-dose CT coronary angiography (CTCA) and low-dose single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). Forty patients referred for elective invasive coronary angiography (CA) were prospectively enrolled to undergo a comprehensive non-invasive evaluation with low-dose CTCA and a dose-reduced stress/rest SPECT-MPI scan (using dedicated reconstruction algorithms for low count scans). The following algorithm was reviewed: CTCA first, followed by a stress-only MPI if a coronary stenosis ({>=} 50% diameter narrowing) or equivocal findings were observed. Only abnormal stress MPI scans were followed by rest MPI. The accuracy of the individualized algorithm to predict coronary revascularization and its mean effective radiation dose were assessed. CTCA documented CAD in 18 and equivocal findings in two patients, thus, requiring additional stress MPI scans. Of these, 16 were abnormal, therefore requiring a rest MPI scan, revealing ischemia in 15 patients. Sensitivity, specificity, negative and positive predictive value, and accuracy of the individualized algorithm for predicting coronary revascularization was 93.3%, 96.0%, 96.0%, 93.3% and 95.0% on a per-patient base. The mean effective radiation dose was significantly lower for the individualized (4.8 {+-} 3.4 mSv) versus the comprehensive method (8.1 {+-} 1.5 mSv) resulting in a total population radiation dose reduction of 132.6 mSv. This new individualized low-dose algorithm allows rapid and accurate prediction of invasive CA findings and of treatment decision with minimized radiation dose. (orig.)

  7. Assessing the effects of different pectins addition on color quality and antioxidant properties of blackberry jam.

    Science.gov (United States)

    Poiana, Mariana-Atena; Munteanu, Melania-Florina; Bordean, Despina-Maria; Gligor, Ramona; Alexa, Ersilia

    2013-01-01

    In the last years pectin and other hydrocolloids were tested for improving the color stability and the retention of bioactive compounds in gelled fruit-based products. In line with these concerns, our study has been directed to quantify the changes in antioxidant status and color indices of blackberry jam obtained with different types of pectin (degree of esterification: DE, degree of amidation: DA) and doses in response to processing and storage for 1, 3 and 6 months at 20°C. Blackberry jam was obtained by a traditional procedure used in households or small-scale systems with different commercial pectins (HMP: high-methoxyl pectin, LMP: low-methoxyl pectin and LMAP: low-methoxyl amidated pectin) added to three concentrations (0.3, 0.7 and 1.0%) and investigated in terms of total monomeric anthocyanins (TMA), antioxidant capacity expressed as ferric reducing antioxidant power (FRAP), total phenolics (TP), color density (CD) and percent of polymeric color, PC (%). Thermal processing resulted in significant depreciation of analyzed parameters reported to the corresponding values of fresh fruit as follows: TMA (69-82%), TP (33-55%) and FRAP (18-52%). Biologically active compounds and color were best retained one day post-processing in jams with LMAP followed by samples with LMP and HMP. Storage for 6 months brings along additional dramatic losses reported to the values recorded one day post-processing as follows: TMA (31-56%), TP (29-51%) and FRAP (20-41%). Also, both processing and storage resulted in significant increases in PC (%). The pectin type and dosage are very influential factors for limiting the alterations occurring in response to processing and storage. The best color retention and the highest TMA, TP and FRAP were achieved by LMAP, followed by LMP and HMP. Additionally, a high level of bioactive compounds in jam could be related to a high dose of pectin. LMAP to a level of 1% is the most indicated to provide the highest antioxidant properties in jam

  8. Standardizing Benchmark Dose Calculations to Improve Science-Based Decisions in Human Health Assessments

    Science.gov (United States)

    Wignall, Jessica A.; Shapiro, Andrew J.; Wright, Fred A.; Woodruff, Tracey J.; Chiu, Weihsueh A.; Guyton, Kathryn Z.

    2014-01-01

    Background: Benchmark dose (BMD) modeling computes the dose associated with a prespecified response level. While offering advantages over traditional points of departure (PODs), such as no-observed-adverse-effect-levels (NOAELs), BMD methods have lacked consistency and transparency in application, interpretation, and reporting in human health assessments of chemicals. Objectives: We aimed to apply a standardized process for conducting BMD modeling to reduce inconsistencies in model fitting and selection. Methods: We evaluated 880 dose–response data sets for 352 environmental chemicals with existing human health assessments. We calculated benchmark doses and their lower limits [10% extra risk, or change in the mean equal to 1 SD (BMD/L10/1SD)] for each chemical in a standardized way with prespecified criteria for model fit acceptance. We identified study design features associated with acceptable model fits. Results: We derived values for 255 (72%) of the chemicals. Batch-calculated BMD/L10/1SD values were significantly and highly correlated (R2 of 0.95 and 0.83, respectively, n = 42) with PODs previously used in human health assessments, with values similar to reported NOAELs. Specifically, the median ratio of BMDs10/1SD:NOAELs was 1.96, and the median ratio of BMDLs10/1SD:NOAELs was 0.89. We also observed a significant trend of increasing model viability with increasing number of dose groups. Conclusions: BMD/L10/1SD values can be calculated in a standardized way for use in health assessments on a large number of chemicals and critical effects. This facilitates the exploration of health effects across multiple studies of a given chemical or, when chemicals need to be compared, providing greater transparency and efficiency than current approaches. Citation: Wignall JA, Shapiro AJ, Wright FA, Woodruff TJ, Chiu WA, Guyton KZ, Rusyn I. 2014. Standardizing benchmark dose calculations to improve science-based decisions in human health assessments. Environ Health

  9. The ecosystem models used for dose assessments in SR-Can

    Energy Technology Data Exchange (ETDEWEB)

    Avila, Rodolfo [Facilia AB, Bromma (Sweden)

    2006-11-15

    chronic contamination. From the simulations for the different release cases, activity concentrations in water and soil are obtained and then multiplied with the aggregated transfer factors to obtain concentrations in food products. For terrestrial ecosystems, the aggregated transfer factors in Becquerel per Kilogram of edible carbon in the food are used to calculate the activity intake and from this the effective dose rate per unit release to an adult individual. For aquatic ecosystems, only doses from the ingestion of water (for lakes) and food (for sea and lakes) are considered, as previous assessments have shown that in these types of ecosystems other exposure pathways give a very low contribution to the total doses. A sensitivity analysis of the ecosystem models is presented in the report, identifying which parameters have the largest effect on the simulation endpoints of interest. The endpoints considered are the fraction of the release that is retained in the ecosystem, the activity concentrations in soil, water and sediments, and the total dose rates from external exposure, inhalation, and ingestion of water and food. These endpoints are evaluated at different times within the simulation and a sensitivity analysis using the Morris method is carried out. For some of the scenarios considered in SR-Can, the LDF concept is not applicable. One of these scenarios comprises the contamination of ground caused by inadvertent drilling into the repository. Doses which would arise for a family using this contaminated ground for housing and food production are estimated. The other scenario which is assessed separately is the release of C-14 and Rn-222 from the repository in gaseous form, entering the biosphere via soil as a diffuse source. Pathways considered are doses from ingestion of C-14 and from inhalation of C-14 and Rn-222 outdoors as well as indoors. For these scenarios, specific dose calculations were carried out. The methods applied for these calculations and the

  10. Dosimetric characterization and organ dose assessment in digital breast tomosynthesis: Measurements and Monte Carlo simulations using voxel phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Mariana, E-mail: marianabaptista@ctn.ist.utl.pt; Di Maria, Salvatore; Barros, Sílvia; Vaz, Pedro [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, km 139,7, Bobadela LRS 2695-066 (Portugal); Figueira, Catarina [Centre for Plasma Physics, School of Mathematics and Physics, Queen’s University, Belfast BT7 1NN (United Kingdom); Sarmento, Marta; Orvalho, Lurdes [Serviço de Imagiologia, Hospital da Luz, Avenida Lusíada, 100, Lisboa 1500-650 (Portugal)

    2015-07-15

    . Regarding the BSF, the results achieved may lead to a MGD correction of about 6%, contributing to the improvement of the current guidelines used in these applications. Finally, considering the MC results obtained for the organ dose study, the radiation doses found for the tissues of the body other than the breast were in the range of tens of μSv, and are in part comparable to the ones obtained in standard DM. Nevertheless, in a single DBT examination, some organs (such as lung and thyroid) receive higher doses (of about 9% and 21%, respectively) with respect to the CC DM acquisition. Conclusions: Taking into account an average breast with a thickness of 4.5 cm, the MGDs for DM and DBT acquisitions were below the achievable value (2.0 mGy) defined by the European protocol. Additionally, in the case of a fusion imaging study (DM + DBT), the MGD for a 4.5 cm thick breast is of the order of 1.88 ± 0.36 mGy. Finally, organ dose evaluations underline the need to improve awareness concerning dose estimation of DBT exams for some organs, especially when radiation risk is assessed by using the effective dose.

  11. Three years of seasonal dose assessment from outdoors gamma exposure in Sao Paulo city, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, Janete C.G.G.; Sanches, Matias P.; Betti, Flavio; Pecequilo, Brigitte R.S., E-mail: janetegc@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Measurements of external (outdoors) gamma exposure from natural background radiation have been used to estimate the average annual doses in Sao Paulo city. Twelve monitoring stations were placed in different regions of the town including both urban (where building materials are present) and outskirts areas. Seasonally surveys observing the four seasons from 2008 to 2010 have been carried out. The data were drawn from a 3-month sampling using the thermoluminescent dosimetry. The effective doses values are quite similar (slightly higher during the winter), so it can be considered that these results are not under significant influence (or variability) of seasonal environmental conditions like temperature, wind or rain. Dose values over the three years period, from Vila Carrao district, exclusively an urban location with mostly no green areas, present the highest values, while the lower values were always obtained for Tucuruvi district, near the biggest urban forest, Parque Estadual da Cantareira. Over the assessed period, the mean of the average annual effective doses was 1.3 {+-} 0.1 mSv.y{sup -1}. For the same period, the average annual background from nuclear and radioactive facility at IPEN was 0.75 {+-} 0.12 mSv.y{sup -1}. (author)

  12. Assessment of the exposure to and dose from radon decay products in normally occupied homes

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.; Jensen, B.; Li, C.S.; Montassier, N.; Wasiolek, P. [Clarkson Univ., Potsdam, NY (United States); Cavallo, A.J.; Gatsby, K.; Socolow, R.H. [Princeton Univ., NJ (United States); James, A.C. [Pacific Northwest Lab., Richland, WA (United States)

    1995-05-01

    The exposure to radon decay products has been assessed in seven homes in the northeastern United States and southeastern Canada. In two of the houses, there was a single individual who smoked cigarettes. There were a variety of heating and cooking appliances among these homes. These studies have provide 565 measurements of the activity-weighted size distributions in these houses. The median value for the equilibrium factor was 0.408 as compared with the previously employed value of 0.50. Using the recently adopted ICRP lung deposition and dosimetry model, the hourly equivalent lung dose rate per unit, radon exposure was estimated for each measured size distribution. Differences between houses with smokers present and absent were noted in the exposure conditions, but the resulting dose rate per unit of radon gas concentration was essentially the same for the two groups. Expressed in terms of ICRP`s unit of effective dose for members of the public, the mean dose rate conversion coefficient with respect to radon gas concentration found in this study was 3.8 nSv h{sup -} Bq{sup -} m{sup -3}. 26 refs., 8 figs., 3 tabs.

  13. Assessing small-volume spinal cord dose for repeat spinal stereotactic body radiotherapy treatments

    Science.gov (United States)

    Ma, Lijun; Kirby, Neil; Korol, Renee; Larson, David A.; Sahgal, Arjun

    2012-12-01

    Spinal cord biologically effective dose (BED) limits are critical to safe spine stereotactic body radiotherapy (SBRT) delivery. In particular, when repeating SBRT to the same site, the problem of adding non-uniform BED distributions within small volumes of spinal cord has yet to be solved. We report a probability-based generalized BED (gBED) model to guide repeat spine SBRT treatment planning. The gBED was formulated by considering the sequential damaging probabilities of repeat spine SBRT treatments. Parameters from the standard linear-quadratic model, such as α/β = 2 Gy for the spinal cord, were applied. We tested the model based on SBRT specific spinal cord tolerance using a simulated and ten clinical repeat SBRT cases. The gBED provides a consistent solution for superimposing non-uniform dose distributions from different fractionation schemes, analogous to the BED for uniform dose distributions. Based on ten clinical cases, the gBED was observed to eliminate discrepancies in the cumulative BED of approximately 5% to 20% within small volumes (e.g. 0.1-2.0 cc) of spinal cord, as compared to a conventional calculation method. When assessing spinal cord tolerance for repeat spinal SBRT treatments, caution should be exercised when applying conventional BED calculations for small volumes of spinal cord irradiated, and the gBED potentially provides more conservative and consistently derived dose surrogates to guide safe treatment planning and treatment outcome modeling.

  14. Assessing Boundary Film Forming Behavior of Phosphonium Ionic Liquids as Engine Lubricant Additives

    Directory of Open Access Journals (Sweden)

    Mayank Anand

    2016-05-01

    Full Text Available The reduction of friction and wear losses in boundary lubrication regime of a piston ring-cylinder liner tribo-system has always been a challenge for engine and lubricant manufacturers. One way is to use lubricant additives, which can form boundary film quickly and reduce the direct contact between asperities. This article focuses on the assessment of boundary film forming behavior of two phosphonium-based ionic liquids (ILs as additives in engine-aged lubricant to further improve its film forming capabilities and hence reduce friction and wear of contacting surfaces. A reciprocating piston ring segment-on-flat coupon under fully flooded lubrication conditions at room temperature (approx. 25 °C was employed. The trihexyltetradecyl phosphonium bis(2-ethylhexyl phosphate and trihexyltetradecyl phosphonium bis(2,4,4-tri-methylpentyl phosphinate ionic liquids were used as additives in 6 vol. % quantity. Benchmark tests were conducted using fully formulated new lubricant of same grade (with and without ILs. Results revealed that the addition of phosphonium ILs to engine-aged lubricant led to quicker initiation of boundary film forming process. In addition, friction and wear performance of engine-aged lubricant improved by the addition of both ILs and these mixtures outperformed the fresh fully formulated oil. Chemical analysis showed higher concentration of phosphorus element on the worn surface indicating presence of ILs in the formed tribofilms.

  15. Determination of 210Po concentration in commercially available infant formulae and assessment of daily ingestion dose

    Directory of Open Access Journals (Sweden)

    Ravi K. Prabhath

    2015-07-01

    Full Text Available A study has been conducted to estimate the concentration of natural radioactive polonium in commercially available packaged infant food formulae available in Mumbai, India and the corresponding daily dose normalized based on its shelf life. Eleven most popular international brands of infant formulae were sourced from market and three aliquots from each sample were analysed for concordant results. Autodeposition method onto a silver planchet from hot dilute acid solution followed by alpha spectrometry was performed for estimation of polonium. Radiochemical recovery was ascertained by the addition of 209Po tracer. Radiochemical recovery of 209Po tracer was ranged from 14.7 to 98.1 %. The 210Po concentration in the samples was in the range of 0.08–0.23 Bq kg−1 on measured date and the corresponding daily dose, calculated on normalized date which is at mid-point of the shelf life of the sample, was ranged from 0.04 to 0.89 μSv d−1 as per the recommended daily consumption. The annual committed effective dose estimated based on the average of daily dose was found to be 150 μSv.

  16. Additional Interventions to Enhance the Effectiveness of Individual Placement and Support: A Rapid Evidence Assessment

    Directory of Open Access Journals (Sweden)

    Naomi Boycott

    2012-01-01

    Full Text Available Topic. Additional interventions used to enhance the effectiveness of individual placement and support (IPS. Aim. To establish whether additional interventions improve the vocational outcomes of IPS alone for people with severe mental illness. Method. A rapid evidence assessment of the literature was conducted for studies where behavioural or psychological interventions have been used to supplement standard IPS. Published and unpublished empirical studies of IPS with additional interventions were considered for inclusion. Conclusions. Six published studies were found which compared IPS alone to IPS plus a supplementary intervention. Of these, three used skills training and three used cognitive remediation. The contribution of each discrete intervention is difficult to establish. Some evidence suggests that work-related social skills and cognitive training are effective adjuncts, but this is an area where large RCTs are required to yield conclusive evidence.

  17. Dose-to-dose variations with single packages of counterfeit medicines and adulterated dietary supplements as a potential source of false negatives and inaccurate health risk assessments.

    Science.gov (United States)

    Venhuis, B J; Zwaagstra, M E; Keizers, P H J; de Kaste, D

    2014-02-01

    In this report, we show three examples of how the variability in dose units in single packages of counterfeit medicines and adulterated dietary supplements may contribute to a false negative screening result and inaccurate health risk assessments. We describe a counterfeit Viagra 100mg blister pack and a box of an instant coffee both containing dose units with and without an active pharmaceutical ingredient (API). We also describe a purportedly herbal slimming product with capsules that mutually differed in API and impurities. The adulterated dietary supplements contained sibutramine, benzyl-sibutramine, N-desmethyl-sibutramine (DMS), N,N-didesmethyl-sibutramine (DDMS) and several other related impurities. Counterfeit medicines and adulterated dietary supplements are a health risk because their quality is unreliable. Health risks are even greater when such unreliability extends to fundamental differences between dose units in one package. Because dose-to-dose variability for these products is unpredictable, the confidence interval of a sample size is unknown. Consequently, the analyses of a selection of dose units may not be representative for the package. In the worst case, counterfeit or unauthorised medicines are not recognised as such or a health risk is not identified. In order to reduce erroneous results particular care should be taken when analysing a composite of dose units, when finding no API in a dietary supplement and when finding conformity in a suspect counterfeit medicine. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. ACUTRI: a computer code for assessing doses to the general public due to acute tritium releases

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, Sumi; Noguchi, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ryufuku, Susumu; Sasaki, Toshihisa; Kurosawa, Naohiro [Visible Information Center, Inc., Tokai, Ibaraki (Japan)

    2002-11-01

    Tritium, which is used as a fuel of a D-T burning fusion reactor, is the most important radionuclide for the safety assessment of a nuclear fusion experimental reactor such as ITER. Thus, a computer code, ACUTRI, which calculates the radiological impact of tritium released accidentally to the atmosphere, has been developed, aiming to be of use in a discussion of licensing of a fusion experimental reactor and an environmental safety evaluation method in Japan. ACUTRI calculates an individual tritium dose based on transfer models specific to tritium in the environment and ICRP dose models. In this calculation it is also possible to analyze statistically on meteorology in the same way as a conventional dose assessment method according to the meteorological guide of the Nuclear Safety Commission of Japan. A Gaussian plume model is used for calculating the atmospheric dispersion of tritium gas (HT) and/or tritiated water (HTO). The environmental pathway model in ACUTRI considers the following internal exposures: inhalation from a primary plume (HT and/or HTO) released from the facilities and inhalation from a secondary plume (HTO) reemitted from the ground following deposition of HT and HTO. This report describes an outline of the ACUTRI code, a user guide and the results of test calculation. (author)

  19. Evolving Adjustments to External (Gamma) Slope Factors for CERCLA Risk and Dose Assessments - 12290

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Stuart [U.S. Environmental Protection Agency (United States)

    2012-07-01

    To model the external exposure pathway in risk and dose assessments of radioactive contamination at Superfund sites, the U.S. Environmental Protection Agency (EPA) uses slope factors (SFs), also known as risk coefficients, and dose conversion factors (DCFs). Without any adjustment these external radiation exposure pathways effectively assumes that an individual is exposed to a source geometry that is effectively an infinite slab. The concept of an 'infinite slab' means that the thickness of the contaminated zone and its aerial extent are so large that it behaves as if it were infinite in its physical dimensions. EPA has been making increasingly complex adjustments to account for the extent of the contamination and its corresponding radiation field to provide more accurate risk and dose assessment modeling when using its calculators. In most instances, the more accurate modeling results derived from these gamma adjustments are less conservative. The notable exception are for some radionuclides in rooms with contaminated walls, ceiling, and floors, and the receptor is in location of the room with the highest amount of radiation exposure, usually the corner of small rooms and the center of large conference rooms. (authors)

  20. Technology Assessment and Roadmap for the Emergency Radiation Dose Assessment Program (ERDAP)

    Science.gov (United States)

    2005-06-01

    sample sources to be exfoliated cells, body fluids such as blood and saliva, and breath. Collection of tissues and other body fluids requiring risky...M.B., and Miller, A . C . , 2001. “Radiation exposure assessment using cytological and molecular biomarkers,” Radiat. Prot. Dosimetry 9 7, 17–23

  1. Numerical system utilising a Monte Carlo calculation method for accurate dose assessment in radiation accidents.

    Science.gov (United States)

    Takahashi, F; Endo, A

    2007-01-01

    A system utilising radiation transport codes has been developed to derive accurate dose distributions in a human body for radiological accidents. A suitable model is quite essential for a numerical analysis. Therefore, two tools were developed to setup a 'problem-dependent' input file, defining a radiation source and an exposed person to simulate the radiation transport in an accident with the Monte Carlo calculation codes-MCNP and MCNPX. Necessary resources are defined by a dialogue method with a generally used personal computer for both the tools. The tools prepare human body and source models described in the input file format of the employed Monte Carlo codes. The tools were validated for dose assessment in comparison with a past criticality accident and a hypothesized exposure.

  2. RADON AND PROGENY SOURCED DOSE ASSESSMENT OF SPA EMPLOYEES IN BALNEOLOGICAL SITES.

    Science.gov (United States)

    Uzun, Sefa Kemal; Demiröz, Işık

    2016-09-01

    This study was conducted in the scope of IAEA project with the name 'Establishing a Systematic Radioactivity Survey and Total Effective Dose Assessment in Natural Balneological Sites' (TUR/9/018), at the Health Physics department of Sarayköy Nuclear Research and Training Center (SANAEM). The aim of this study is estimation of radon and progeny sourced effective dose for the people who are working at the spa facilities by measuring radon activity concentration (RAC) at the ambient air of indoor spa pools and dressing rooms. As it is known, the source of the radon gas is the radium content of the earth crust. Therefore, thermal waters coming from ground may contain dissolved radon and the radon can diffuse water to air. So the ambient air of spa pools can contain serious RAC that depends on a lot of parameters. In this regard, RAC measurements were executed at the 70 spa facilities in Turkey. The measurements were done with both active and passive methods at ambient air of spa pools and dressing rooms. Thus, active measurements were carried out by using the Alphaguard(®) with diffusion mode during half an hour, and passive measurements were carried out by using the humidity resistive CR-39 radon detectors during 2 months. Results show that RAC values at ambient air of spa pools varies between 13 Bq m(-3) and 10 kBq m(-3) Because long-term measurements are more reliable, if it is available, for dose calculations passive radon measurements (with CR-39 detectors) at ambient air of spa pools and dressing rooms were used, otherwise active measurement results were used. With the measurement by the conversion coefficients of ICRP 65 and occupational data of the employees has got from questionary forms, effective dose values were calculated. According to the calculations, spa employees are exposed to annual average dose between 0.05 and 29 mSv because of radon and progeny.

  3. Dose Assessment of Eye and Its Components in Proton Therapy by Monte Carlo Method

    Directory of Open Access Journals (Sweden)

    Marzieh Tavakol

    2014-04-01

    Full Text Available Introduction Proton therapy is used to treat malignant tumors such as melanoma inside the eye. Proton particles are adjusted according to various parameters such as tumor size and position and patient’s distance from the proton source. The purpose of this study was to assess absorbed doses in eyes and various tumors found in the area of sclera and choroid and the adjacent tissues in radiotherapy while changing most important proton therapy parameters such as moderators thickness (1.5-1.9 cm, exposure radius (0.5-0.8 cm, and proton energy beam (53.5-65 MeV. Materials and Methods A proton therapy system of Laboratori Nazionali del Sud-INFNwas simulated by Monte Carlo method. Moreover, the eye and its components were simulated using concentric spheres. To obtain a more accurate results, real density of eye components such as cornea and lens, were applied for simulation. Then, the absorbed dose of eye and eye tumor, in choroid and sclera areas, were calculated by Monte Carlo method. Results The absorbed dose in tumoral region of eye was calculated to be about 12.5 ±0.006Gy in one day with energy 62 MeV for a therapy session, which is suitable for treatment. However, normal eye cells received at most 11.01 Gy which is high. Conclusion The amount of absorbed dose in tumoral cells is noticeable. Therefore, accurate treatment planning, patient immobility and fine calibration of proton-therapy system and its simulator are very important to reduce the absorbed dose of healthy cells.

  4. Screening level dose assessment of aquatic biota downstream of the Marcoule nuclear complex in southern France.

    Science.gov (United States)

    St-Pierre, S; Chambers, D B; Lowe, L M; Bontoux, J G

    1999-09-01

    Aquatic biota in the Rhone River downstream of the Marcoule nuclear complex in France are exposed to natural sources of radiation and to radioactivity released from the Marcoule complex. A simple conservative screening level model was used to estimate the range of concentrations in aquatic media (water, sediments, and aquatic organisms) of both artificial and natural radionuclides and the consequent absorbed (whole body) dose rates for aquatic organisms. Five categories of aquatic organisms were studied, namely, submerged aquatic plants (phanerogam), non-bottom-feeding fish, bottom-feeding fish, mollusca, and fish-eating birds. The analysis was based on the radionuclide concentrations reported in four consecutive annual radioecological monitoring reports published by French agencies with nuclear regulatory responsibilities. The results of this assessment were used to determine, qualitatively, the magnitude of any potential health impacts on each of the five categories of aquatic organisms studied. The range of dose rate estimates ranged over three orders of magnitude, with maximum dose rates estimated to be in the order of 1 to 10 microGy h(-1). These maximum dose rates are a factor 40 or more below the international guideline intended to ensure the protection of aquatic populations (about 400 microGy h(-1)), and a factor ten or more below the level which may trigger the need for a more detailed evaluation of potential ecological consequences to the exposed populations (about 100 microGy h(-1)). As a result, chronic levels of radioactivity, artificial and natural, measured in aquatic media downstream of Marcoule are unlikely to result in adverse health impacts on the categories and species of aquatic organisms studied. Thus, based on the screening level analysis discussed in this paper, a more detailed evaluation of the dose rates does not appear to be warranted.

  5. ASSESSMENT OF THE E 920 ADDITIVE (L - CYSTEINE IN RELATION TO SOME PROBLEMS OF MODERN FOOD INDUSTRY

    Directory of Open Access Journals (Sweden)

    Radiana Maria TAMBA BEREHOIU

    2013-01-01

    Full Text Available This paper aims to assess the current state of knowledge about the use of L - cysteine in food industry, regarding certain cultural, legal, technological, toxicological, and other aspects that influence the attitude of the consumerstowards food. Use of L - cysteine and its derivatives in bakery allows the optimizing of the technological characteristics of flours and their higher recovery, by using products with high added value. Use the E 920 additivein human food is subject to the cultural and religious controversy, due to the generalized process of obtaining this additive from animal products (keratin. Our study shows that these controversies will be overcome when industrialfermentative technologies of L - cysteine production will be generalized in the market. There exist no data on thepotential toxicity of L - cysteine in the usual doses which are used in the baking industry. The only threat to the status of E 920 as a safe additive is the excitotoxic potential, suggested in several recent studies. Also, there exists a potential for extending the use of L - cysteine in the food industry in order to reduce the contamination degree withcertain chemicals having carcinogen potential, such as acrylamide and mycotoxins.

  6. Assessment of doses caused by electrons in thin layers of tissue-equivalent materials, using MCNP.

    Science.gov (United States)

    Heide, Bernd

    2013-10-01

    Absorbed doses caused by electron irradiation were calculated with Monte Carlo N-Particle transport code (MCNP) for thin layers of tissue-equivalent materials. The layers were so thin that the calculation of energy deposition was on the border of the scope of MCNP. Therefore, in this article application of three different methods of calculation of energy deposition is discussed. This was done by means of two scenarios: in the first one, electrons were emitted from the centre of a sphere of water and also recorded in that sphere; and in the second, an irradiation with the PTB Secondary Standard BSS2 was modelled, where electrons were emitted from an (90)Sr/(90)Y area source and recorded inside a cuboid phantom made of tissue-equivalent material. The speed and accuracy of the different methods were of interest. While a significant difference in accuracy was visible for one method in the first scenario, the difference in accuracy of the three methods was insignificant for the second one. Considerable differences in speed were found for both scenarios. In order to demonstrate the need for calculating the dose in thin small zones, a third scenario was constructed and simulated as well. The third scenario was nearly equal to the second one, but a pike of lead was assumed to be inside the phantom in addition. A dose enhancement (caused by the pike of lead) of ∼113 % was recorded for a thin hollow cylinder at a depth of 0.007 cm, which the basal-skin layer is referred to in particular. Dose enhancements between 68 and 88 % were found for a slab with a radius of 0.09 cm for all depths. All dose enhancements were hardly noticeable for a slab with a cross-sectional area of 1 cm(2), which is usually applied to operational radiation protection.

  7. Performance assessment of the BEBIG MultiSource high dose rate brachytherapy treatment unit.

    Science.gov (United States)

    Palmer, Antony; Mzenda, Bongile

    2009-12-21

    A comprehensive system characterisation was performed of the Eckert & Ziegler BEBIG GmbH MultiSource High Dose Rate (HDR) brachytherapy treatment unit with an (192)Ir source. The unit is relatively new to the UK market, with the first installation in the country having been made in the summer of 2009. A detailed commissioning programme was devised and is reported including checks of the fundamental parameters of source positioning, dwell timing, transit doses and absolute dosimetry of the source. Well chamber measurements, autoradiography and video camera analysis techniques were all employed. The absolute dosimetry was verified by the National Physical Laboratory, UK, and compared to a measurement based on a calibration from PTB, Germany, and the supplied source certificate, as well as an independent assessment by a visiting UK centre. The use of the 'Krieger' dosimetry phantom has also been evaluated. Users of the BEBIG HDR system should take care to avoid any significant bend in the transfer tube, as this will lead to positioning errors of the source, of up to 1.0 mm for slight bends, 2.0 mm for moderate bends and 5.0 mm for extreme curvature (depending on applicators and transfer tube used) for the situations reported in this study. The reason for these errors and the potential clinical impact are discussed. Users should also note the methodology employed by the system for correction of transit doses, and that no correction is made for the initial and final transit doses. The results of this investigation found that the uncorrected transit doses lead to small errors in the delivered dose at the first dwell position, of up to 2.5 cGy at 2 cm (5.6 cGy at 1 cm) from a 10 Ci source, but the transit dose correction for other dwells was accurate within 0.2 cGy. The unit has been mechanically reliable, and source positioning accuracy and dwell timing have been reproducible, with overall performance similar to other existing HDR equipment. The unit is capable of high

  8. Assessment of the Technologies for Molecular Biodosimetry for Human Low-Dose Radiation Exposure Symposium

    Energy Technology Data Exchange (ETDEWEB)

    Matthew A. Coleman Ph.D.; Narayani Ramakrishnan, Ph.D.; Sally A. Amundson; James D. Tucker, Ph.D.; Stephen D. Dertinger, Ph.D.; Natalia I. Ossetrova, Ph.D.; Tao Chen

    2009-11-16

    Exposure to ionizing radiation produces few immediate outwardly-visible clinical signs, yet, depending on dose, can severely damage vital physiological functions within days to weeks and produce long-lasting health consequences among survivors. In the event of a radiological accident, the rapid evaluation of the individual absorbed dose is paramount to discriminate the worried but unharmed from those individuals who must receive medical attention. Physical, clinical and biological dosimetry are usually combined for the best dose assessment. However, because of the practical limits of physical and clinical dosimetry, many attempts have been made to develop a dosimetry system based on changes in biological parameters, including techniques for hematology, biochemistry, immunology, cytogenetics, etc. Lymphocyte counts and chromosome aberrations analyses are among the methods that have been routinely used for estimating radiation dose. However, these assays require several days to a week to be completed and therefore cannot be used to obtain a fast estimate of the dose during the first few days after exposure when the information would be most critical for identifying victims of radiation accidents who could benefit the most by medical intervention. The steadily increasing sophistication in our understanding of the early biochemical responses of irradiated cells and tissues provides the opportunity for developing mechanism-based biosignatures of exposure. Compelling breakthroughs have been made in the technologies for genome-scale analysis of cellular transcriptional and proteomic profiles. There have also been major strides in the mechanistic understanding of the early events in DNA damage and radiation damage products, as well as in the cellular pathways that lead to radiation injury. New research with genomic- and proteomic-wide tools is showing that within minutes to hours after exposure to ionizing radiation protein machines are modified and activated, and large

  9. Equivalent dose, effective dose and risk assessment from panoramic radiography to the critical organs of head and neck region

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Bong Hae; Nah, Kyung Soo [Dept. of Dental Radiology, College of Dentistry, Pusan National University, Pusan (Korea, Republic of); Lee, Ae Ryeon [Dept. of Pediatric Dentistry, College of Dentistry, Pusan National University, Pusan (Korea, Republic of)

    1995-08-15

    The purpose of this study was to evaluate the equivalent and effective dose, and estimate radiation risk to the critical organs of head and neck region from the use of adult and child mode in panoramic radiography. The results were as follows. 1. The salivary glands showed the highest equivalent and effective dose in adult and child mode. The equivalent and effective dose in adult mode were 837 {mu}Sv and 20.93 {mu}Sv, those in child mode were 462 {mu}Sv and 11.54 {mu}Sv, respectively. 2. Total effective doses to the critical head and neck organs were estimated 34.2l {mu}Sv in adult mode, 20.14 {mu}Sv in child mode. From these data, the probabilities of stochastic effect from adult and child mode were 2.50xl0{sup -6} and 1.47x10{sup -6} 3. The other remainder showed the greatest risk of fatal cancer. The risk estimate were 4.5 and 2.7 fatal malignancies in adult and child mode from million examinations. The bone marrow and thyroid gland showed about 0.1 fatal cancer in adult. and child mode from these examinations.

  10. Development and Validation of a Questionnaire to Assess Carbohydrate and Insulin-Dosing Knowledge in Youth With Type 1 Diabetes

    OpenAIRE

    Koontz, Michaela B.; Cuttler, Leona; Palmert, Mark R; O'Riordan, MaryAnn; BORAWSKI, ELAINE A.; McConnell, Judy; Kern, Elizabeth O.

    2009-01-01

    OBJECTIVE The American Diabetes Association advocates insulin regimens for youth with type 1 diabetes that involve adjusting insulin dose based on carbohydrate intake and blood glucose level. Implementing these regimens requires knowledge about carbohydrate content of foods and subsequent calculations of insulin dose, skills that may be difficult to gauge in practice. Therefore, we sought to develop and validate a questionnaire, the PedCarbQuiz (PCQ), to assess carbohydrate and insulin-dosing...

  11. SU-E-T-616: Plan Quality Assessment of Both Treatment Planning System Dose and Measurement-Based 3D Reconstructed Dose in the Patient

    Energy Technology Data Exchange (ETDEWEB)

    Olch, A [University of Southern California, Los Angeles, CA (United States)

    2015-06-15

    Purpose: Systematic radiotherapy plan quality assessment promotes quality improvement. Software tools can perform this analysis by applying site-specific structure dose metrics. The next step is to similarly evaluate the quality of the dose delivery. This study defines metrics for acceptable doses to targets and normal organs for a particular treatment site and scores each plan accordingly. The input can be the TPS or the measurement-based 3D patient dose. From this analysis, one can determine whether the delivered dose distribution to the patient receives a score which is comparable to the TPS plan score, otherwise replanning may be indicated. Methods: Eleven neuroblastoma patient plans were exported from Eclipse to the Quality Reports program. A scoring algorithm defined a score for each normal and target structure based on dose-volume parameters. Each plan was scored by this algorithm and the percentage of total possible points was obtained. Each plan also underwent IMRT QA measurements with a Mapcheck2 or ArcCheck. These measurements were input into the 3DVH program to compute the patient 3D dose distribution which was analyzed using the same scoring algorithm as the TPS plan. Results: The mean quality score for the TPS plans was 75.37% (std dev=14.15%) compared to 71.95% (std dev=13.45%) for the 3DVH dose distribution. For 3/11 plans, the 3DVH-based quality score was higher than the TPS score, by between 0.5 to 8.4 percentage points. Eight/11 plans scores decreased based on IMRT QA measurements by 1.2 to 18.6 points. Conclusion: Software was used to determine the degree to which the plan quality score differed between the TPS and measurement-based dose. Although the delivery score was generally in good agreement with the planned dose score, there were some that improved while there was one plan whose delivered dose quality was significantly less than planned. This methodology helps evaluate both planned and delivered dose quality. Sun Nuclear Corporation has

  12. Radiation dose assessment for the biota of terrestrial ecosystems in the shoreline zone of the Chernobyl nuclear power plant cooling pond.

    Science.gov (United States)

    Oskolkov, Boris Ya; Bondarkov, Mikhail D; Gaschak, Sergey P; Maksimenko, Andrey M; Hinton, Thomas G; Coughlin, Daniel; Jannik, G Timothy; Farfán, Eduardo B

    2011-10-01

    Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. This paper addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from 90Sr and 137Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to draw down naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature.

  13. RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.

    2011-10-01

    Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. The article addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from {sup 90}Sr and {sup 137}Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to drawdown naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature.

  14. DOSE ASSESSMENT OF THE FINAL INVENTORIES IN CENTER SLIT TRENCHES ONE THROUGH FIVE

    Energy Technology Data Exchange (ETDEWEB)

    Collard, L.; Hamm, L.; Smith, F.

    2011-05-02

    In response to a request from Solid Waste Management (SWM), this study evaluates the performance of waste disposed in Slit Trenches 1-5 by calculating exposure doses and concentrations. As of 8/19/2010, Slit Trenches 1-5 have been filled and are closed to future waste disposal in support of an ARRA-funded interim operational cover project. Slit Trenches 6 and 7 are currently in operation and are not addressed within this analysis. Their current inventory limits are based on the 2008 SA and are not being impacted by this study. This analysis considers the location and the timing of waste disposal in Slit Trenches 1-5 throughout their operational life. In addition, the following improvements to the modeling approach have been incorporated into this analysis: (1) Final waste inventories from WITS are used for the base case analysis where variance in the reported final disposal inventories is addressed through a sensitivity analysis; (2) Updated K{sub d} values are used; (3) Area percentages of non-crushable containers are used in the analysis to determine expected infiltration flows for cases that consider collapse of these containers; (4) An updated representation of ETF carbon column vessels disposed in SLIT3-Unit F is used. Preliminary analyses indicated a problem meeting the groundwater beta-gamma dose limit because of high H-3 and I-129 release from the ETF vessels. The updated model uses results from a recent structural analysis of the ETF vessels indicating that water does not penetrate the vessels for about 130 years and that the vessels remain structurally intact throughout the 1130-year period of assessment; and (5) Operational covers are included with revised installation dates and sets of Slit Trenches that have a common cover. With the exception of the modeling enhancements noted above, the analysis follows the same methodology used in the 2008 PA (WSRC, 2008) and the 2008 SA (Collard and Hamm, 2008). Infiltration flows through the vadose zone are

  15. Comparison of conventional Injection Mould Inserts to Additively Manufactured Inserts using Life Cycle Assessment

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Bey, Niki; Mischkot, Michael

    2016-01-01

    Polymer Additive Manufacturing can be used to produce soft tooling inserts for injection moulding. Compared to conventional tooling, the energy and time consumption during production are significantly lower. As the life time of such inserts is significantly shorter than the life time of traditional...... of their potential environmental impact and yield throughout the development and pilot phase. Insert geometry is particularly advantageous for pilot production and small production sizes. In this research, Life Cycle Assessment is used to compare the environmental impact of soft tooling by Additive Manufacturing...... (using Digital Light Processing) and three traditional methods for the manufacture of inserts (milling of brass, steel, and aluminium) for injection moulds during the pre-production phase....

  16. Ionic liquids as lubricants or lubrication additives: an ecotoxicity and biodegradability assessment.

    Science.gov (United States)

    Stolte, Stefan; Steudte, Stephanie; Areitioaurtena, Olatz; Pagano, Francesco; Thöming, Jorg; Stepnowski, Piotr; Igartua, Amaya

    2012-11-01

    This paper reports on the (eco)toxicity and biodegradability of ionic liquids considered for application as lubricants or lubrication additives. Ammonium- and pyrrolidinium-based cations combined with methylsulphate, methylsulphonate and/or (CF(3)SO(2))(2)N(-) anions were investigated in tests to determine their aquatic toxicity using water fleas Daphnia magna, green algae Selenastrum capricornutum and marine bacteria (Vibrio fischeri). Additional test systems with an isolated enzyme (acetylcholinesterase) and isolated leukaemia cells from rats (IPC-81) were used to assess the biological activity of the ionic liquids. These compounds generally exhibit low acute toxicity and biological activity. Their biodegradability was screened according to OECD test procedures 301 B and 301 F. For choline and methoxy-choline ionic liquids ready biodegradability was observed within 5 or 10 d, respectively. Some of the compounds selected have a considerable potential to contribute to the development of more sustainable products and processes.

  17. Thermal imaging for assessment of electron-beam freeform fabrication (EBF3) additive manufacturing deposits

    Science.gov (United States)

    Zalameda, Joseph N.; Burke, Eric R.; Hafley, Robert A.; Taminger, Karen M.; Domack, Christopher S.; Brewer, Amy; Martin, Richard E.

    2013-05-01

    Additive manufacturing is a rapidly growing field where 3-dimensional parts can be produced layer by layer. NASA's electron beam freeform fabrication (EBF3) technology is being evaluated to manufacture metallic parts in a space environment. The benefits of EBF3 technology are weight savings to support space missions, rapid prototyping in a zero gravity environment, and improved vehicle readiness. The EBF3 system is composed of 3 main components: electron beam gun, multi-axis position system, and metallic wire feeder. The electron beam is used to melt the wire and the multi-axis positioning system is used to build the part layer by layer. To insure a quality deposit, a near infrared (NIR) camera is used to image the melt pool and solidification areas. This paper describes the calibration and application of a NIR camera for temperature measurement. In addition, image processing techniques are presented for deposit assessment metrics.

  18. Comparison of conventional Injection Mould Inserts to Additively Manufactured Inserts using Life Cycle Assessment

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Bey, Niki; Mischkot, Michael

    2016-01-01

    Polymer Additive Manufacturing can be used to produce soft tooling inserts for injection moulding. Compared to conventional tooling, the energy and time consumption during production are significantly lower. As the life time of such inserts is significantly shorter than the life time of traditional...... of their potential environmental impact and yield throughout the development and pilot phase. Insert geometry is particularly advantageous for pilot production and small production sizes. In this research, Life Cycle Assessment is used to compare the environmental impact of soft tooling by Additive Manufacturing...... (using Digital Light Processing) and three traditional methods for the manufacture of inserts (milling of brass, steel, and aluminium) for injection moulds during the pre-production phase....

  19. Biological shielding assessment and dose rate calculation for a neutron inspection portal

    Science.gov (United States)

    Donzella, A.; Bonomi, G.; Giroletti, E.; Zenoni, A.

    2012-04-01

    With reference to the prototype of neutron inspection portal built and successfully tested in the Rijeka seaport (Croatia) within the EURITRACK (EURopean Illicit Trafficking Countermeasures Kit) project, an assessment of the biological shielding in different set-up configurations of a future portal has been calculated with MCNP Monte Carlo code in the frame of the Eritr@C (European Riposte against Illicit TR@ffiCking) project. In the configurations analyzed the compliance with the dose limits for workers and the population stated by the European legislation is provided by appropriate shielding of the neutron sources and by the delimitation of a controlled area.

  20. Assessment of a low dose of IV midazolam used orally for conscious sedation in pediatric dentistry

    OpenAIRE

    M. Mortazavi; Pourhashemi SJ; Khosravi, M. B.; S Ashtari; F. Ghaderi

    2009-01-01

    Background and the purpose of the study: Midazolam is preferably used in pediatric dentistry for quick onset of action and recovery. The aim of this prospective, observer-blind and placebo-controlled study was to assess the efficacy of a low dose of oral midazolam in modification of  the behavior of young pediatric dental patients. Methods: Forty children aged 3 to 5 years who displayed ratings 1 or 2 on the Frankl Scale and  were healthy by the American Society of Anesthesi...

  1. A Review of Models for Dose Assessment Employed by SKB in the Renewed Safety Assessment for SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, George [Imperial College of Science Technology and Medicine (United Kingdom)

    2002-09-01

    This document provides a critical review, on behalf of SSI, of the models employed by the Swedish Nuclear Fuel and Waste Management Co (SKB) for dose assessment in the renewed safety assessment for the final repository for radioactive operational waste (SFR 1) in Forsmark, Sweden. The main objective of the review is to examine the models used by SKB for radiological dose assessment in a series of evolving biotopes in the vicinity of the Forsmark repository within a time frame beginning in 3000 AD and extending beyond 7500 AD. Five biosphere models (for coasts, lakes, agriculture, mires and wells) are described in Report TR-01-04. The principal consideration of the review is to determine whether these models are fit for the purpose of dose evaluation over the time frames involved and in the evolving sequence of biotopes specified. As well as providing general observations and comments on the modelling approach taken, six specific questions are addressed, as follows. Are the assumptions underlying the models justifiable? Are all reasonably foreseeable environmental processes considered? Has parameter uncertainty been sufficiently and reasonably addressed? Have sufficient models been used to address all reasonably foreseeable biotopes? Are the transitions between biotopes modelled adequately (specifically, are initial conditions for developing biotopes adequately specified by calculations for subsiding biotopes)? Have all critical radionuclides been identified? It is concluded that, in general, the assumptions underlying most of the models are justifiable. The exceptions are a) the rather simplistic approach taken in the Coastal Model and b) the lack of consideration of wild foods and age-dependence when calculating exposures of humans to radionuclides via dietary pathways. Most foreseeable processes appear to have been accounted for within the constraints of the models used, although it is recommended that attention be paid to future climate states when considering

  2. Valdose program: methodologies for dose assessment in internal contamination, 1997 census; Programma valdose: metodologie di valutazione della dose da contaminazione interna, censimento 1997

    Energy Technology Data Exchange (ETDEWEB)

    Castellani, C.M.; Battisti, P.; Tarroni, G. [ENEA, Centro Ricerche `Ezio Clementel`, Bologna (Italy). Dip. Ambiente

    1998-12-31

    Dose assessment in internal dosimetry needs computational and interpretative tools that allow carrying out, as a first step, an evaluation of intake on the base of bioassay measurements or WBC measurements, and as a second step, dose evaluation on the base of estimated intake. In the frame of the MIDIA Co-ordination (WBC operating in Italy), in the first months of 1997 a census on methodologies for dose evaluation in internal contamination has been proposed. A technical form has been sent to all the WBC Centres allowing an accurate description of modalities used in each centre. 9 out of 17 centres sent the answers to the technical form in time. In this paper all the forms filled in are reported. A careful comparative evaluation of the answers has been made both for routine monitoring and for special monitoring. The various radionuclides present in the Italian reality, calculation methodologies both for intake and dose, hypotheses adopted for date, path and modalities of contaminations are also presented. Proposals for conforming to the methodology in Italy after the introduction of the models following ICRP 60 publication that are the base of the Euratom 96/29 Directive are also discussed. [Italiano] La valutazione di dose in contaminazione interna necessita di strumenti interpretativi che permettano di effettuare in una prima la valutazione dell`intake sulla base delle misure dei campioni biologici o del corpo intero (WBC), ed in una seconda fase la valutazione della dose sulla base dell`intake. All`interno del coordinamento MIDIA dei WBC operanti in Italia e` stato proposto, nel primo trimestre del 1997, un censimento sulle metodologie di valutazione di dose da contaminazione interna. Ai diversi centri e` stato inviato una scheda tecnica che, mediante un particolareggiato schema di domande, aiutava i diversi centri nella esposizione delle modalita` di valutazione di dose che ogni centro segue. 9 au 17 centri WBC operanti al momemnto in Italia hanno inviato la

  3. Dose assessment of SiC nanoparticle dispersions during in vitro assays

    Energy Technology Data Exchange (ETDEWEB)

    Mejia, Jorge, E-mail: jorge.mejiamendoza@unamur.be [University of Namur, Research Centre for the Physics of Matter and Radiation (LARN-PMR) NARILIS (Belgium); Piret, Jean-Pascal; Noeel, Florence [University of Namur, Research Unit in Cellular Biology (URBC) NARILIS (Belgium); Masereel, Bernard [University of Namur, Department of Pharmacy NAMEDIC, Namur Thrombosis and Homeostasis Center (NTHC) NARILIS (Belgium); Toussaint, Olivier [University of Namur, Research Unit in Cellular Biology (URBC) NARILIS (Belgium); Lucas, Stephane [University of Namur, Research Centre for the Physics of Matter and Radiation (LARN-PMR) NARILIS (Belgium)

    2013-08-15

    Here, we show that key physicochemical parameters of commercial Silicon Carbide nanoparticles, such as the primary particles of about 53 nm in size, the agglomerates size, and the surface composition, are considerably modified with respect to the pristine conditions, during in vitro assessment. The use of sample conditioning stages, such as the pre-dispersion in aqueous media and the subsequent dispersion in a culture medium specific to the in vitro assay, produce modifications as the absorption of N, C, and O, from the culture medium, in the nanoparticles surface. Our results show that the sedimented dose, fraction of sedimented NPs during incubation and consequently in contact with cells seeded at the bottom, of Silicon Carbide nanoparticles can be measured from the particle size distribution obtained using a centrifugal liquid sedimentation technique. It is underlined that the variations observed in the physicochemical properties are related to the in vitro assay conditions. Culture medium and incubation time are found to influence the most the sedimented dose and consequently the cells dose uptake.

  4. Assessment of Dose to the Nursing Infant from Radionuclides in Breast Milk

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL

    2010-03-01

    A computer software package was developed to predict tissue doses to an infant due to intake of radionuclides in breast milk based on bioassay measurements and exposure data for the mother. The package is intended mainly to aid in decisions regarding the safety of breast feeding by a mother who has been acutely exposed to a radionuclide during lactation or pregnancy, but it may be applied to previous intakes during the mother s adult life. The package includes biokinetic and dosimetric information needed to address intake of Co-60, Sr-90, Cs-134, Cs-137, Ir-192, Pu-238, Pu-239, Am-241, or Cf-252 by the mother. It has been designed so that the library of biokinetic and dosimetric files can be expanded to address a more comprehensive set of radionuclides without modifying the basic computational module. The methods and models build on the approach used in Publication 95 of the International Commission on Radiological Protection (ICRP 2004), Doses to Infants from Ingestion of Radionuclides in Mothers Milk . The software package allows input of case-specific information or judgments such as chemical form or particle size of an inhaled aerosol. The package is expected to be more suitable than ICRP Publication 95 for dose assessment for real events or realistic planning scenarios in which measurements of the mother s excretion or body burden are available.

  5. Image quality and dose assessment in digital breast tomosynthesis: A Monte Carlo study

    Science.gov (United States)

    Baptista, M.; Di Maria, S.; Oliveira, N.; Matela, N.; Janeiro, L.; Almeida, P.; Vaz, P.

    2014-11-01

    Mammography is considered a standard technique for the early detection of breast cancer. However, its sensitivity is limited essentially due to the issue of the overlapping breast tissue. This limitation can be partially overcome, with a relatively new technique, called digital breast tomosynthesis (DBT). For this technique, optimization of acquisition parameters which maximize image quality, whilst complying with the ALARA principle, continues to be an area of considerable research. The aim of this work was to study the best quantum energies that optimize the image quality with the lowest achievable dose in DBT and compare these results with the digital mammography (DM) ones. Monte Carlo simulations were performed using the state-of-the-art computer program MCNPX 2.7.0 in order to generate several 2D cranio-caudal (CC) projections obtained during an acquisition of a standard DBT examination. Moreover, glandular absorbed doses and photon flux calculations, for each projection image, were performed. A homogeneous breast computational phantom with 50%/50% glandular/adipose tissue composition was used and two compressed breast thicknesses were evaluated: 4 cm and 8 cm. The simulated projection images were afterwards reconstructed with an algebraic reconstruction tool and the signal difference to noise ratio (SDNR) was calculated in order to evaluate the image quality in DBT and DM. Finally, a thorough comparison between the results obtained in terms of SDNR and dose assessment in DBT and DM was performed.

  6. Analysis of regional left ventricular function by low-dose dobutamine radionuclide ventriculography; Is it useful to assess myocardial viability

    Energy Technology Data Exchange (ETDEWEB)

    Takeyasu, Noriyuki; Watanabe, Shigeyuki; Ajisaka, Ryuichi (Tsukuba Univ., Ibaraki (Japan). Inst. of Clinical Medicine) (and others)

    1994-01-01

    The purpose of this study was to assess the value of low-dose dobutamine radionuclide ventriculography in the assessment of myocardial viability. The subjects were 40 patients who underwent both dobutamine radionuclide ventriculography and Tl-201 myocardial single photon emission computed tomography (SPECT). Scintigraphic data were acquired before and one minute after iv injection of 5 [mu]g/kg/min of dobutamine using equilibrium method. Left ventricular sector analysis was made to measure various left ventricular function indicators. In addition, sector analysis from SPECT images both at rest and exercise was made for the quantitative assessment of perfusion images, including normal, hypoperfusion and hyperperfusion, Dobutamine caused a significantly increased regional ejection fraction (rEF) equally in both normal and hypoperfusion zones on SPECT. In both zones, regional one to three ejection fraction (r1/3EF) was increased by dobutamine. This was significantly greater than that in normal zones on SPECT. Defect zones, as shown on SPECT, were less significantly subjected to both rEF and r1/3EF than the other zones; however, some zones showed the same degree of increase as hypoperfusion zones, suggesting myocardial viability. There was no consistent tendency for diastolic parameters. Dobutamine radionuclide ventriculography appears to have a potential for the assessment of myocardial viability by determining regional ventricular function, unlike the value of Tl-201 myocardial SPECT. (N.K.).

  7. DOSE ASSESSMENT FOR INTAKE OF TRITIATED WATER IN HUMANS: ROLE OF TRITIUM INCORPORATION IN ORGANIC MATTER

    Directory of Open Access Journals (Sweden)

    M. I. Balonov

    2016-01-01

    for two-compartment modeling. The recurrent model with tritiated water excretion was more adjusted to human physiology. Contribution of organically bound tritium to effective dose can be somewhat higher than that to absorbed dose defined in this work. The presented dose assessment system can be used when specified individual absorbed dose reconstruction in tissues is necessary following accidental intake of large tritium activities.

  8. Safety of a single low-dose of primaquine in addition to standard artemether-lumefantrine regimen for treatment of acute uncomplicated Plasmodium falciparum malaria in Tanzania.

    Science.gov (United States)

    Mwaiswelo, Richard; Ngasala, Billy E; Jovel, Irina; Gosling, Roland; Premji, Zul; Poirot, Eugenie; Mmbando, Bruno P; Björkman, Anders; Mårtensson, Andreas

    2016-06-10

    This study assessed the safety of the new World Health Organization (WHO) recommendation of adding a single low-dose of primaquine (PQ) to standard artemisinin-based combination therapy (ACT), regardless of individual glucose-6-phosphate dehydrogenase (G6PD) status, for treatment of acute uncomplicated Plasmodium falciparum malaria in Tanzania. Men and non-pregnant, non-lactating women aged ≥1 year with uncomplicated P. falciparum malaria were enrolled and randomized to either standard artemether-lumefantrine (AL) regimen alone or with a 0.25 mg/kg single-dose of PQ. PQ was administered concomitantly with the first AL dose. All drug doses were supervised. Safety was evaluated between days 0 and 28. G6PD status was assessed using rapid test (CareStart™) and molecular genotyping. The primary endpoint was mean percentage relative reduction in haemoglobin (Hb) concentration (g/dL) between days 0 and 7 by genotypic G6PD status and treatment arm. Overall, 220 patients, 110 per treatment arm, were enrolled, of whom 33/217 (15.2 %) were phenotypically G6PD deficient, whereas 15/110 (13.6 %) were genotypically hemizygous males, 5/110 (4.5 %) homozygous females and 22/110 (20 %) heterozygous females. Compared to genotypically G6PD wild-type/normal [6.8, 95 % confidence interval (CI) 4.67-8.96], only heterozygous patients in AL arm had significant reduction in day-7 mean relative Hb concentration (14.3, 95 % CI 7.02-21.55, p=0.045), however, none fulfilled the pre-defined haemolytic threshold value of ≥25 % Hb reduction. After adjustment for baseline parasitaemia, Hb, age and sex the mean relative Hb reduction was not statistically significant in both heterozygous and hemizygous/homozygous patients in both arms. A majority of the adverse events (AEs) were mild and unrelated to the study drugs. However, six (4.4 %) episodes, three per treatment arm, of acute haemolytic anaemia occurred between days 0 and 7. Three occurred in phenotypically G6PD deficient

  9. Dose assessment from chronic exposure to industrial NORM in iron ore processing.

    Science.gov (United States)

    Dal Molin, Franck; Fisher, Raymond; Frost, David; Anderson, David R; Read, David

    2017-09-05

    Radiological exposures due to naturally occurring radioactive material (NORM) can occur during a wide range of work-related activities in the mineral processing and chemical industries. However, evaluation of such exposures in industrial settings remains a difficult exercise owing inter alia to the large number of personnel, operations and plants affected; assumptions that often have to be made concerning the actual duration and frequency of exposures; the complex chemistry and radioactive disequilibria involved and typically, the paucity of historical data. In our study, the challenges associated with assessing chronic exposure to fugitive dust enriched in 210Pb and 210Po and the determination of the associated internal dose by inhalation and ingestion are described by reference to a case study undertaken at an iron ore sintering plant between June 2013 and July 2015. The applicability of default dose coefficients and biokinetic models provided by the International Commission for Radiological Protection (ICRP) was verified by combining air and dust monitoring with information on the characteristics of the aerosols and in-vitro solubility experiments. The disparity between particulate matter 100 microns or less in diameter (PM100), particulate matter 10 microns or less in diameter (PM10) and 210Pb/210Po activity concentrations observed over the different monitoring campaigns and sampling locations confirmed that use of positional short-term monitoring surveys to extrapolate intake over a year was not appropriate and could lead to unrealistic intake and dose figures. Personal air sampling is more appropriate for estimating the dose in such situations, though it is not always practical and may collect insufficient quantities of material for radiochemical analysis; this is an important constraint when dealing with low specific activity materials. © 2017 IOP Publishing Ltd.

  10. Development of low-dose protocols for thin-section CT assessment of cystic fibrosis in pediatric patients.

    LENUS (Irish Health Repository)

    O'Connor, Owen J

    2010-12-01

    To develop low-dose thin-section computed tomographic (CT) protocols for assessment of cystic fibrosis (CF) in pediatric patients and determine the clinical usefulness thereof compared with chest radiography.

  11. PECULIARITIES OF CURRENT DOSE ASSESSMENT FOR CHILDREN LIVING IN THE TERRITORIES RADIOACTIVELY CONTAMINATED DUE TO THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    A. V. Gromov

    2011-01-01

    Full Text Available The article outlines peculiarities of current dose assessment for the children living in the territories radioactively contaminated due to the Chernobyl accident. The results of annual exposure dose assessment for the children of various age groups and adult population of three subject territories of the Russian Federation referred to the zones of radioactive contamination are presented. A comparison of obtained estimations is done.

  12. Bayesian Analysis for Food-Safety Risk Assessment: Evaluation of Dose-Response Functions within WinBUGS

    OpenAIRE

    Williams, Michael S.; Ebel, Eric D.; Jennifer A Hoeting

    2011-01-01

    Bayesian methods are becoming increasingly popular in the field of food-safety risk assessment. Risk assessment models often require the integration of a dose-response function over the distribution of all possible doses of a pathogen ingested with a specific food. This requires the evaluation of an integral for every sample for a Markov chain Monte Carlo analysis of a model. While many statistical software packages have functions that allow for the evaluation of the integral, this functional...

  13. [Requirements for drug approval and additional benefits assessment: Regulatory aspects and experiences].

    Science.gov (United States)

    Broich, K; Löbker, W; Schulte, A; Beinlich, P; Müller, T

    2016-04-01

    The early assessment of benefits of newly approved drugs with novel active substances or new applications, which came into force on 1 January 2011 still represents a challenge to all parties involved. This article highlights the definitions, regulatory requirements and interaction between drug marketing approval and early assessment of benefits in Germany. The constellation of an extensively harmonized European and even international drug authorization process with a predominantly national regulation of drug reimbursement situation inevitably causes friction, which could be markedly reduced through early joint advisory discussions during the planning phase for pivotal clinical trials. During the year 2015 the Federal Institute for Drugs and Medical Devices (BfArM) carried out 300 scientific advice procedures of which 34 were concerned with applications in the field of indications for the central nervous system (CNS). In comparison 98 advisory meetings were held by the Federal Joint Committee (G-BA) of which the BfArM provided advice in 12 instances and in 2 cases on CNS indications. Study design, endpoints and appropriate comparative therapies are the key issues in exchanges and discussions between the BfArM, the G‑BA and applicants. Under these aspects the BfArM and G‑BA promote an early and consistent involvement in early advice procedures regarding the prerequisites for drug approval and assessment of additional benefits.

  14. CANCER RISKS ATTRIBUTABLE TO LOW DOSES OF IONIZING RADIATION - ASSESSING WHAT WE REALLY KNOW?

    Science.gov (United States)

    Cancer Risks Attributable to Low Doses of Ionizing Radiation - What Do We Really Know?AbstractHigh doses of ionizing radiation clearly produce deleterious consequences in humans including, but not exclusively, cancer induction. At very low radiation doses the situatio...

  15. Risk assessment of additives through soft drinks and nectars consumption on Portuguese population: a 2010 survey.

    Science.gov (United States)

    Diogo, Janina S G; Silva, Liliana S O; Pena, Angelina; Lino, Celeste M

    2013-12-01

    This study investigated whether the Portuguese population is at risk of exceeding ADI levels for acesulfame-K, saccharin, aspartame, caffeine, benzoic and sorbic acid through an assessment of dietary intake of additives and specific consumption of four types of beverages, traditional soft drinks and soft drinks based on mineral waters, energetic drinks, and nectars. The highest mean levels of additives were found for caffeine in energetic drinks, 293.5mg/L, for saccharin in traditional soft drinks, 18.4 mg/L, for acesulfame-K and aspartame in nectars, with 88.2 and 97.8 mg/L, respectively, for benzoic acid in traditional soft drinks, 125.7 mg/L, and for sorbic acid in soft drinks based on mineral water, 166.5 mg/L. Traditional soft drinks presented the highest acceptable daily intake percentages (ADIs%) for acesulfame-K, aspartame, benzoic and sorbic acid and similar value for saccharin (0.5%) when compared with soft drinks based on mineral water, 0.7%, 0.08%, 7.3%, and 1.92% versus 0.2%, 0.053%, 0.6%, and 0.28%, respectively. However for saccharin the highest percentage of ADI was obtained for nectars, 0.9%, in comparison with both types of soft drinks, 0.5%. Therefore, it is concluded that the Portuguese population is not at risk of exceeding the established ADIs for the studied additives.

  16. EcoDoses. Improving radiological assessment of doses to man from terrestrial ecosystems: A status report for the NKS-B activity 2006

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, S.; Andersson, K.G. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Thoerring, H.; Liland, A. (Norwegian Radiation Protection Authority (Norway)); Joensen, H.P. (Frooskaparsetur Foeroya, Faroe Islands, Torshavn (Denmark)); Isaksson, M. (Goeteborg Univ. (Sweden)); Saxen, R.; Kostiainen, E. (Radiation and Nuclear Safety Authority (STUK) (Finland)); Suolanen, V. (VTT Technical Research Centre of Finland, Espoo (Finland)); Palsson, S.E. (Geislavarnir rikisins (Iceland))

    2009-03-15

    The overall aim of the NKS-B EcoDoses activity is to improve the prediction of doses to humans from consumption of radioactively contaminated food. For this purpose, various published and unpublished datasets have been compiled and applied in developing refined parameterisation for existing food dose models. The ECOSYS model developed in Germany after the Chernobyl accident has been applied as the basis for the investigations. This model can be operated both with discrete releases adequately representing a nuclear power plant accident, and with continuous or multiple releases, as observed in the nuclear weapons testing period. The modelling has revealed that it is essential to ensure that case-specific values are applied for a range of parameters, adequately reflecting the actual conditions with respect to geology, season, climate and demography. In connection with this year's work on the activity, sensitivity studies have been conducted with the ECOSYS model, in which the influence on ingestion dose estimates of a number of parameters has been evaluated in relation to Faroese conditions. The importance of applying location specific data to estimate dose is pinpointed, and it is also concluded that dose predictions for a small and distinct area like the Faroese, where not all of the many parameters required to run ECOSYS optimally have been adequately assessed in recent years, can be associated with considerable uncertainty. A Finnish study has been made in relation to modelling of radiocaesium behaviour in lakes. This study was carried out using a compartmental model that is included as a module in the DETRA dose assessment tool. A total of nine different input parameters (distribution coefficients, run-off from the catchment, erosion from the catchment, sedimentation rate in the lakes, lake water exchange rate, and biological half-lives in four fish species) were varied, and particularly distribution coefficients and lake water exchange rates were

  17. The Art of Making Assessment Anti-Venom: Injecting Assessment in Small Doses to Create a Faculty Culture of Assessment

    Science.gov (United States)

    Kramer, Philip I.

    2009-01-01

    Many college faculty react to student outcomes assessment the way most people react when they see a rattlesnake within striking distance. Common faculty reactions to the perceived threat of assessment include metaphorically running away and throwing rocks or sticks at it. Like a hiker in the desert doing her best to avoid being struck when she…

  18. Personnel dose assessment due to the normal operations with the artificial radiation sources according to the data from the unified system of individual dose control (USIDC

    Directory of Open Access Journals (Sweden)

    Yu. I. Stepkin

    2016-01-01

    Full Text Available The aim of the study was personnel dose assessment due to the normal operations with the artificial radiation sources. The article is based on the data from the Unified System of Individual Dose Control and Voronezh Region’s radiation-hygienic passport. The data from No.1-DOZ “Information on personnel exposure doses under normal operation of technogenic ionizing radiation sources” and over a period of 2006-2010 years were analyzed. In 2006-2015, the number of organizations, which submitted form No.1-DOZ “Information on personnel exposure doses under normal operation of technogenic ionizing radiation sources”, increased from 175 to 229. In amount of the radiation facilities, Novovoronezh Nuclear Power Plant is the first. Novovoronezh NPP has 1512 sources, which amounts to 51,9% from all sources in Voronezh Region (2915. Health care facilities have 869 radiation sources or 29,8%. X-ray machines are the main part of these sources (844 health care facilities or 97,1% of all medical sources. Industrial sources occupy third place with 305 facilities or 10,5% of all considered sources. In 2015, according to the data from Voronezh Region’s radiation-hygienic passport, the number of “A” group personnel were 4237, the number of “B” group personnel were 2341. The average individual dose for personnel was over the range from 0.66 to 2.02 mSv. Collective dose was from 4.16 to 11.79 man-sieverts per year. The increase of number of the radiation sources has attended with the decrease of individual and collective doses. The most likely it is related to using the modern facilities. In 2015, the maximum value of the average individual dose of “A” group personnel was registered in Voronezh regional hospital (6.17 mSv y–1. There are medical facilities with unsealed and sealed sources in this hospital. In 2006-2015, the average individual doses of personnel of all radiation facilities that use radiation sources in Voronezh

  19. Quantitative and qualitative comparison of standard-dose and low-dose pediatric head computed tomography: a retrospective study assessing the effect of adaptive statistical iterative reconstruction.

    Science.gov (United States)

    Kilic, Koray; Erbas, Gonca; Guryildirim, Melike; Konus, Oznur Leman; Arac, Mehmet; Ilgit, Erhan; Isik, Sedat

    2013-01-01

    Our aim was to assess the effect of adaptive statistical iterative reconstruction (ASIR) on pediatric head computed tomography (CT) examinations. We retrospectively reviewed 305 pediatric head CT examinations. The study population consisted of standard dose (STD, n = 152) examinations reconstructed with filtered back projection and low dose (LD, n = 153) examinations reconstructed with 30% (LD30) and 0% (LD0) ASIR. We compared groups by means of radiation dose, noise measures, and visual grading. Student t test, 1-way analysis of variance test, and Mann-Whitney U test were used for statistical analysis. The dose in the LD30 group was significantly lower (29%) than that in the STD group (P < 0.001). The noise in the white matter (P < 0.001), SNR (P < 0.001), and subjective image noise (P = 0.044) was significantly better in the STD group than those in the LD30 group. There was no significant difference between LD30 and STD groups in the sharpness (P = 0.141), diagnostic acceptability (P = 0.079), and artifacts (P = 0.750) and contrast-to-noise ratio (P = 0.718). In conclusion, we found that a blend of 30% ASIR in a 16-slice multidetector CT produces diagnostically acceptable pediatric head CT examinations with a 29% less dose.

  20. Assessment of low-dose cisplatin as a model of nausea and emesis in beagle dogs, potential for repeated administration.

    Science.gov (United States)

    Kenward, Hannah; Pelligand, Ludovic; Elliott, Jonathan

    2014-08-01

    Cisplatin is a highly emetogenic cancer chemotherapy agent, which is often used to induce nausea and emesis in animal models. The cytotoxic properties of cisplatin also cause adverse events that negatively impact on animal welfare preventing repeated administration of cisplatin. In this study, we assessed whether a low (subclinical) dose of cisplatin could be utilized as a model of nausea and emesis in the dog while decreasing the severity of adverse events to allow repeated administration. The emetic, nausea-like behavior and potential biomarker response to both the clinical dose (70 mg/m2) and low dose (15 mg/m2) of cisplatin was assessed. Plasma creatinine concentrations and granulocyte counts were used to assess adverse effects on the kidneys and bone marrow, respectively. Nausea-like behavior and emesis was induced by both doses of cisplatin, but the latency to onset was greater in the low-dose group. No significant change in plasma creatinine was detected for either dose groups. Granulocytes were significantly reduced compared with baseline (P = 0.000) following the clinical, but not the low-dose cisplatin group. Tolerability of repeated administration was assessed with 4 administrations of an 18 mg/m2 dose cisplatin. Plasma creatinine did not change significantly. Cumulative effects on the granulocytes occurred, they were significantly decreased (P = 0.03) from baseline at 3 weeks following cisplatin for the 4th administration only. Our results suggest that subclinical doses (15 and 18 mg/m2) of cisplatin induce nausea-like behavior and emesis but have reduced adverse effects compared with the clinical dose allowing for repeated administration in crossover studies.

  1. ASSESSMENT OF EFFECTIVE DOSE FROM CONE BEAM CT IMAGING IN SPECT/CT EXAMINATION IN COMPARISON WITH OTHER MODALITIES.

    Science.gov (United States)

    Tonkopi, Elena; Ross, Andrew A

    2016-12-01

    The aim of this study was to assess radiation dose from the cone beam computed tomography (CBCT) component of single photon emission tomography/computed tomography (SPECT/CT) examinations and to compare it with the radiopharmaceutical related dose as well as dose from multidetector computed tomography (MDCT). Effective dose (ED) from computed tomography (CT) was estimated using dose-length product values and anatomy-specific conversion factors. The contribution from the SPECT component was evaluated using ED per unit administered activity for the radiopharmaceuticals listed in the International Commission on Radiological Protection Publications 80 and 106. With the exception of cardiac studies (0.11 mSv), the CBCT dose (3.96-6.04 mSv) was similar to that from the radiopharmaceutical accounting for 29-56 % of the total ED from the examination. In comparison with MDCT examinations, the CBCT dose was 48 and 42 % lower for abdomen/pelvis and chest/abdomen/pelvis scans, respectively, while in the chest the CBCT scan resulted in higher dose (23 %). Radiation dose from the CT component should be taken into consideration when evaluating total SPECT/CT patient dose.

  2. Assessment of CT dose to the fetus and pregnant female patient using patient-specific computational models.

    Science.gov (United States)

    Xie, Tianwu; Poletti, Pierre-Alexandre; Platon, Alexandra; Becker, Christoph D; Zaidi, Habib

    2017-09-08

    This work provides detailed estimates of the foetal dose from diagnostic CT imaging of pregnant patients to enable the assessment of the diagnostic benefits considering the associated radiation risks. To produce realistic biological and physical representations of pregnant patients and the embedded foetus, we developed a methodology for construction of patient-specific voxel-based computational phantoms based on existing standardised hybrid computational pregnant female phantoms. We estimated the maternal absorbed dose and foetal organ dose for 30 pregnant patients referred to the emergency unit of Geneva University Hospital for abdominal CT scans. The effective dose to the mother varied from 1.1 mSv to 2.0 mSv with an average of 1.6 mSv, while commercial dose-tracking software reported an average effective dose of 1.9 mSv (range 1.7-2.3 mSv). The foetal dose normalised to CTDIvol varies between 0.85 and 1.63 with an average of 1.17. The methodology for construction of personalised computational models can be exploited to estimate the patient-specific radiation dose from CT imaging procedures. Likewise, the dosimetric data can be used for assessment of the radiation risks to pregnant patients and the foetus from various CT scanning protocols, thus guiding the decision-making process. • In CT examinations, the absorbed dose is non-uniformly distributed within foetal organs. • This work reports, for the first time, estimates of foetal organ-level dose. • The foetal brain and skeleton doses present significant correlation with gestational age. • The conceptus dose normalised to CTDI vol varies between 0.85 and 1.63. • The developed methodology is adequate for patient-specific CT radiation dosimetry.

  3. The addition of low-dose leucovorin to the combination of 5-fluorouracil-levamisole does not improve survival in the adjuvant treatment of Dukes' C colon cancer

    NARCIS (Netherlands)

    Bleeker, WA; Mulder, NH; Hermans, J; Otter, R; Plukker, JT

    2000-01-01

    Purpose: To assess the effect of the addition of leucovorin to the combination of 5-fluorouracil (5-FU)-levamisole on recurrence risk and overall survival in patients after a resection with curative intent of a Dukes' C colon cancer. Patients and methods: Five hundred patients with Dukes' C colon ca

  4. Potential radionuclide emissions from stacks on the Hanford site, Part 1: Dose assessment

    Energy Technology Data Exchange (ETDEWEB)

    Davis, W.E.; Barnett, J.M. [Westinghouse Hanford Company, Richland, WA (United States)

    1995-02-01

    On February 3, 1993, the U.S. Department of Energy, Richland Operations Office received a Compliance Order and Information Request from the Director of the Air and Toxics Division of the U.S. Environmental Protection Agency, Region 10. The Compliance Order requires RL to evaluate all radionuclide emission points at the Hanford Site to determine which are subject to continuous emission monitoring requirements in 40 CFR 61, Subpart H, and to continuously monitor radionuclide emissions in accordance with requirements in 40 CFR 61.93. The Information Request required RL to provide a written Compliance Plan to meet the requirements of the Compliance Order. A Compliance Plan was submitted to EPA, Region 10, on April 30, 1993. The Compliance Plan specified that a dose assessment would be performed for 84 Westinghouse Hanford Company stacks registered with the Washington State Department of Health on the Hanford Site. Stacks that have the potential emissions to cause an effective dose equivalent to a maximum exposed individual greater than 0.1 mrem/y must be monitored continuously for radionuclide emissions. Five methods were approved by EPA, Region 10 for performing the assessments: Release Fractions from Appendix D of 40 CFR 61, Back Calculations Using A HEPA Filtration Factor, Nondestructive Assay of HEPA Filters, A Spill Release Fraction, and Upstream of HEPA Filter Air Concentrations. The first two methods were extremely conservative for estimating releases. The third method, which used a state-of-the-art portable gamma spectrometer, yielded surprising results from the distribution of radionuclides on the HEPA filters. All five methods are described. Assessments using a HEPA Filtration Factor for back calculations identified 32 stacks that would have emissions that would cause an EDE to the MEI greater than 0.1 mrem y{sup {minus}1}. The number was reduced to 15 stacks when the other methods were applied. The paper discusses reasons for the overestimates.

  5. CT outperforms radiographs at a comparable radiation dose in the assessment for spondylolysis

    Energy Technology Data Exchange (ETDEWEB)

    Fadell, Michael F.; Stewart, Jaime R.; Harned, Roger K.; Ingram, James D.; Miller, Angie L.; Strain, John D.; Weinman, Jason P. [Children' s Hospital Colorado, Department of Radiology, Aurora, CO (United States); University of Colorado Hospital, Department of Radiology, Aurora, CO (United States); Gralla, Jane [University of Colorado Denver, Department of Pediatrics, Aurora, CO (United States); Bercha, Istiaq [Children' s Hospital Colorado, Department of Radiology, Aurora, CO (United States)

    2015-07-15

    Lumbar spondylolysis, a unilateral or bilateral fracture at pars interarticularis, is a common cause of low back pain in children. The initial imaging study in the diagnosis of lumbar spondylolysis has historically been lumbar spine radiographs; however, radiographs can be equivocal or false-negative. Definitive diagnosis can be achieved with computed tomography (CT), but its use has been limited due to the dose of ionizing radiation to the patient. By limiting the z-axis coverage to the relevant anatomy and optimizing the CT protocol, we are able to provide a definitive diagnosis of fractures of the pars interarticularis at comparable or lower radiation dose than commonly performed lumbar spine radiographs. As there is no gold standard for the diagnosis of spondylolysis besides surgery, we compared interobserver agreement and degree of confidence to determine which modality is preferable. Sixty-two patients with low back pain ages 5-18 years were assessed for the presence of spondylolysis. Forty-seven patients were evaluated by radiography and 15 patients were evaluated by limited field-of-view CT. Both radiographic and CT examinations were assessed anonymously in random order for the presence or absence of spondylolysis by six raters. Agreement was assessed among raters using a Fleiss Kappa statistic for multiple raters. CT provided a significantly higher level of agreement among raters than radiographs (P < 0.001). The overall Kappa for rater agreement with radiographs was 0.24, 0.34 and 0.40 for 2, 3 or 4 views, respectively, and 0.88 with CT. Interobserver agreement is significantly greater using limited z-axis coverage CT when compared with radiographs. Radiologist confidence improved significantly with CT compared to radiographs regardless of the number of views. (orig.)

  6. Addition of sub-anaesthetic dose of ketamine reduces gag reflex during propofol based sedation for upper gastrointestinal endoscopy: A prospective randomised double-blind study

    Directory of Open Access Journals (Sweden)

    Manish Tandon

    2014-01-01

    Full Text Available Background and Aims: Gag reflex is unwanted during upper gastrointestinal endoscopy (UGIE. Experimental studies have demonstrated that N-methyl-D-aspartate receptor antagonism prevents gag reflex. We conducted a study to determine if sub-anaesthetic doses of ketamine, added to propofol, reduce the incidence of gag reflex. Methods: This prospective, randomised, double-blind and placebo-controlled study was done in a tertiary care hospital. A total of 270 patients undergoing UGIE, were randomised to propofol (P group (n = 135 or propofol plus ketamine (PK group (n = 135. All patients received propofol boluses titrated to Ramsay sedation score of not <4. Patients in PK group in addition received ketamine, 0.15 mg/kg immediately before the first-propofol dose. Top-up doses of propofol were given as required. Stata 11 software (StataCorp. was used to calculate the proportion of patients with gag reflex and the corresponding relative risk. Propofol consumed and time to recovery in the two groups was compared using Student′s t-test and Cox proportional hazards regression respectively. Results: Significantly, fewer patients in the PK group had gag reflex compared to the P group (3 vs. 23, risk ratio = 0.214, 95% confidence interval [CI], 0.07-0.62; P = 0.005. The incidence of hypotension (6 vs. 16, risk ratio = 0.519, 95% CI = 0.25-1.038; P = 0.06, number of required airway manoeuvres (4 vs. 19, risk ratio = 0.32, 95% CI = 0.13-0.74; P = 0.014, median time to recovery (4 min vs. 5 min, hazard ratio = 1.311, 95% CI = 1.029-1.671; P = 0.028 and propofol dose administered (152 mg vs. 167 mg, 95% CI = 4.74-24.55; P = 0.004 was also less in the PK group compared to the P group. Conclusion: Ketamine in sub-anaesthetic dose decreases gag reflex during UGIE.

  7. Assessment of the climate commitments and additional mitigation policies of the United States

    Science.gov (United States)

    Greenblatt, Jeffery B.; Wei, Max

    2016-12-01

    Current intended nationally determined contributions (INDCs) are insufficient to meet the Paris Agreement goal of limiting temperature change to between 1.5 and 2.0 °C above pre-industrial levels, so the effectiveness of existing INDCs will be crucial to further progress. Here we assess the likely range of US greenhouse gas (GHG) emissions in 2025 and whether the US’s INDC can be met, on the basis of updated historical and projected estimates. We group US INDC policies into three categories reflecting potential future policies, and model 17 policies across these categories. With all modelled policies included, the upper end of the uncertainty range overlaps with the 2025 INDC target, but the required reductions are not achieved using reference values. Even if all modelled policies are implemented, additional GHG reduction is probably required; we discuss several potential policies.

  8. Structured Additive Quantile Regression for Assessing the Determinants of Childhood Anemia in Rwanda.

    Science.gov (United States)

    Habyarimana, Faustin; Zewotir, Temesgen; Ramroop, Shaun

    2017-06-17

    Childhood anemia is among the most significant health problems faced by public health departments in developing countries. This study aims at assessing the determinants and possible spatial effects associated with childhood anemia in Rwanda. The 2014/2015 Rwanda Demographic and Health Survey (RDHS) data was used. The analysis was done using the structured spatial additive quantile regression model. The findings of this study revealed that the child's age; the duration of breastfeeding; gender of the child; the nutritional status of the child (whether underweight and/or wasting); whether the child had a fever; had a cough in the two weeks prior to the survey or not; whether the child received vitamin A supplementation in the six weeks before the survey or not; the household wealth index; literacy of the mother; mother's anemia status; mother's age at the birth are all significant factors associated with childhood anemia in Rwanda. Furthermore, significant structured spatial location effects on childhood anemia was found.

  9. Quality assessment of delineation and dose planning of early breast cancer patients included in the randomized Skagen Trial 1

    DEFF Research Database (Denmark)

    Francolini, Giulio; Thomsen, Mette S; Yates, Esben S

    2017-01-01

    Background and purpose: To report on a Quality assessment (QA) of Skagen Trial 1, exploring hypofractionation for breast cancer patients with indication for regional nodal radiotherapy. Material and methods: Deviations from protocol regarding target volume delineations and dose parameters (Dmin, ...... coverage in most patients. Inter-observer variability in contouring was low. Dose parameters were in harmony with protocol regardless original or GS segmentation.......Background and purpose: To report on a Quality assessment (QA) of Skagen Trial 1, exploring hypofractionation for breast cancer patients with indication for regional nodal radiotherapy. Material and methods: Deviations from protocol regarding target volume delineations and dose parameters (Dmin......, Dmax, D98%, D95% and D2%) from randomly selected dose plans were assessed. Target volume delineation according to ESTRO guidelines was obtained through atlas based automated segmentation and centrally approved as gold standard (GS). Dice similarity scores (DSC) with original delineations were measured...

  10. Characterizing dose-responses of catalase to nitrofurazone exposure in model ciliated protozoan Euplotes vannus for ecotoxicity assessment: enzyme activity and mRNA expression.

    Science.gov (United States)

    Li, Jiqiu; Zhou, Liang; Lin, Xiaofeng; Yi, Zhenzhen; Al-Rasheid, Khaled A S

    2014-02-01

    In environmental studies, some biological responses, known as biomarkers, have been used as a powerful bioassay tool for more than four decades. Disparity between enzyme activity and mRNA abundance leads to correlation equivocality, which makes the application of biomarkers for environmental risk assessment more complicated. This study investigates this disparity in the case of catalase when used as a biomarker for detecting ecotoxicity induced by antibiotics in aquatic ecosystems. In particular, dose-responses for catalase activity and mRNA expression abundance were investigated in Euplotes vannus which were exposed to graded doses of nitrofurazone for several discrete durations, and dose-response models were developed to characterize the dose-response dynamics. Significant differences were found in both catalase activity and mRNA expression abundance among the E. vannus treated with nitrofurazone. Catalase activity showed a hormetic-like effect in terms of dose-response, characterized by a biphasic relationship which was more clearly evident after a longer exposure period, while mRNA expression abundance increased linearly with the exposure duration. Additionally, the correlation between catalase activity and mRNA expression abundance reversed along with the duration of exposure to nitrofurazone. Taken together, our results demonstrate that catalase mRNA expression offers a more straightforward dose-response model than enzyme activity. Our findings suggest that both catalase enzyme activity and mRNA expression abundance can be used jointly as bioassay tools for detecting ecotoxicity induced by nitrofurazone in aquatic ecosystems.

  11. Assessment of individual dose utilization vs. physician prescribing recommendations for recombinant activated factor VII (rFVIIa) in paediatric and adult patients with congenital haemophilia and alloantibody inhibitors (CHwI): the Dosing Observational Study in Hemophilia (DOSE).

    Science.gov (United States)

    Gruppo, R A; Kessler, C M; Neufeld, E J; Cooper, D L

    2013-07-01

    Recent data from the Dosing Observational Study in Hemophilia diary study has described home treatment with recombinant activated factor VII (rFVIIa) in congenital haemophilia with inhibitors (CHwI). The current analysis compares prescribed and patient/caregiver-reported rFVIIa administration in paediatric and adult CHwI patients in this study. Patients with ≥ 4 bleeding episodes within a 3-month period prescribed rFVIIa as first-line therapy for bleeding episodes were eligible. Patients/caregivers completed a diary for ≥ 90 days or until the patient experienced four bleeds. Initial, total and mean rFVIIa doses reported for each bleeding episode were calculated and compared with the physician-prescribed doses. Of 52 enrolled patients (25 children; 27 adults), 39 (75%) completed the study. Children and adults had similar mean durations of bleeding episodes. Both patient groups were administered higher initial rFVIIa doses for joint bleeds than prescribed: median (range) 215.2 (74.1-400.0) mcg kg(-1) vs. 200.0 (61.0-270.0) mcg kg(-1) for children, and 231.3 (59.3-379.7) mcg kg(-1) vs. 123.0 (81.0-289.0) mcg kg(-1) for adults. The median infused dose for joint bleeds was higher in adults than children (175.2 vs. 148.0 mcg kg(-1) ), but children received significantly more doses per joint bleed than adults (median 6.5 vs. 3.0). The median total dose per joint bleed was higher in children than adults (1248.7 vs. 441.6). For children and adults, both initial and additional doses administered for bleeds were higher than prescribed. Children received higher total doses per bleed due to an increased number of infusions per bleed.

  12. Comparison of passive and active radon measurement methods for personal occupational dose assessment

    Directory of Open Access Journals (Sweden)

    Hasanzadeh Elham

    2016-01-01

    Full Text Available To compare the performance of the active short-term and passive long-term radon measurement methods, a study was carried out in several closed spaces, including a uranium mine in Iran. For the passive method, solid-state nuclear track detectors based on Lexan polycarbonate were utilized, for the active method, AlphaGUARD. The study focused on the correlation between the results obtained for estimating the average indoor radon concentrations and consequent personal occupational doses in various working places. The repeatability of each method was investigated, too. In addition, it was shown that the radon concentrations in different stations of the continually ventilated uranium mine were comparable to the ground floor laboratories or storage rooms (without continual ventilation and lower than underground laboratories.

  13. EcoDoses. Improving radiological assessment of doses to man from terrestrial ecosystems. A status report for the NKS-B project 2004

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Sven P.; Isaksson, M.; Nilsson, Elisabeth (and others)

    2005-07-01

    The NKS B-programme EcoDoses project started in 2003 as a collaboration between all the Nordic countries. The aim of the project is to improve the radiological assessments of doses to man from terrestrial ecosystems. The present report sums up the work performed in the second phase of the project. The main topics in 2004 have been: (i) A continuation of previous work with a better approach for estimating global fallout on a regional or national scale, based on a correlation between precipitation and deposition rates. (ii) Fur-ther extension of the EcoDoses milk database. Estimation of effective ecological half lives of {sup 137}Cs in cows milk focussing on suitable post-Chernobyl time-series. Modelling integrated transfer of {sup 13}7{sup C}s to cow's milk from Nordic countries. (iii) Determination of effective ecological half lives for fresh water fish from Nordic lakes. (iv) Investigate ra-dioecological sensitivity for Nordic populations. (v) Food-chain modelling using the Eco-sys-model, which is the underlying food- and dose-module in several computerised deci-sion-making systems. (au)

  14. EcoDoses improving radiological assessment of doses to man from terrestrial ecosystems. A status report for the NKS-B project 2003

    Energy Technology Data Exchange (ETDEWEB)

    Bergan, T. [Lavrans Skuterud, Haevard Thoerring (Norway); Liland, A. [Norwegian Radiation Protection Authority (NRPA) (Denmark)] (eds.)

    2004-05-01

    The NKS B-programme EcoDoses project started in 2003 as a collaboration between all the Nordic countries. The aim of the project is to improve the radiological assessments of doses to man from terrestrial ecosystems. The first part, conducted in 2003, has focussed on an extensive collation and review of both published and unpublished data from all the Nordic countries for the nuclear weapons fallout period and the post-Chemobyl period. This included data on radionuclides in air filters, precipitation, soil samples, milk and reindeer. Based on this, an improved model for estimating radioactive fallout based on precipitation data during the nuclear weapons fallout period has been developed. Effective ecological half- lives for 137Cs and 90Sr in milk have been calculated for the nuclear weapons fallout period. For reindeer the ecological half- lives for 137Cs have been calculated for both the nuclear weapons fallout period and the post-Chemobyl period. The data were also used to compare modelling results with observed concentrations. This was done at a workshop where the radioecological food-and-dose module in the ARGOS decision support system was used to predict transfer of deposited radionuclides to foodstuffs and subsequent radiation doses to man. The work conducted the first year is presented in this report and gives interesting, new results relevant for terrestrial radioecology. (au)

  15. Quality assurance of the EORTC trial 22881/10882 : 'assessment of the role of the booster dose in breast conserving therapy'; The Dummy Run

    Energy Technology Data Exchange (ETDEWEB)

    Tienhoven, G. van; Bree, N.A.M. van; Mijnheer, B.J.; Bartelink, H. (Nederlands Kanker Inst. ' Antoni van Leeuwenhoekhuis' , Amsterdam (Netherlands) the EORTC Radiotherapy Group)

    1991-12-01

    The EORTC trial 22881/10882 is a randomised trial with the aim to assess the role of the boost dose in breast conserving therapy in stage I and II breast cancer.In order to detect potential protocol deviations concerning irradiation technique and in dose specification procedure of participating institutions before actual patient accrual, a Dummy Run was performed. Three transverse sections of a patient were sent to 16 institutions with a request to make a 3-plane treatment plan according to protocol prescriptions. A treatment chart and beam data were also requested for recalculation of the dose. Additional information was asked in a questionnaire. On evaluation, the techniques differed considerably with respect to photon beam energy, varying between {sup 60}Co gamma-rays and 8MV X-rays, and use of wedge filters. Two institutions did not apply wedges, whereas wedge angles in the other institutions varied between 6deg and 45 deg. Twelve institutions used collimator rotation and/or a table wedge to diminish the amount of irradiated lung volume. The dose was specified in a point according to the protocol prescription in 11 institutions and to the 90, 95 or 100% isodose curve in four. Twelve institutions applied lung density corrections during treatment planning, while nine reported problems with their planning system in off-axis dose distribution calculation and/or the stimulation of collimator rotation. Recalculation of dose at the isocentre showed agreement within 2% compared with stated dose. Dose reported in the tumor excision area varied between 93 and 100%. It can be concluded that good accordance and high quality breast irradiation can be achieved by all institutions participating in the trial, provided a few recommendations are followed. The results of this analysis show the necessity and usefulness of a quality assurance programme at the initial phase of a clinical trial. (author). 27 refs.; 3 figs.; 4 tabs.

  16. Efeito da filtração adicional nas doses de radiação e na qualidade das imagens nos exames videofluoroscópicos Effect of additional filtration on radiation doses and image quality in videofluoroscopic studies

    Directory of Open Access Journals (Sweden)

    Milton Melciades Barbosa Costa

    2009-12-01

    Full Text Available OBJETIVO: Investigar o efeito da adição de filtros de alumínio (1 mm e cobre (0,4 mm na redução das doses efetivas de radiação e na qualidade das imagens em exames videofluoroscópicos. MATERIAIS E MÉTODOS: Ao tubo de raios X adicionou-se câmara de ionização conectada a um eletrômetro para medir o produto kerma-área, com técnica de 65 kVp e 0,7 mA, sem e com adição dos filtros. Foi medida resolução espacial, a de baixo contraste e tons de cinza, utilizando os objetos de teste de Leeds. Quinze voluntários tiveram o produto kerma-área/minuto do estudo faríngeo comparados, dez com filtração e base e cinco com adição dos filtros associados. RESULTADOS: A adição dos filtros separados ou associados produziu expressiva redução do produto kerma-área, com ganho na qualidade das imagens videofluoroscópicas determinado pela maior separação dos tons de cinza e aumento da relação brilho/contraste da curva de cinza. CONCLUSÃO: A interposição adicional de filtros de alumínio e cobre, em especial quando associados, melhora a qualidade das imagens, com expressiva redução das doses de radiação necessárias à sua geração.OBJECTIVE: The purpose of thys study was to investigate the effect of the addition of aluminum (1 mm and copper (0.4 mm filters on effective radiation doses and image quality in videofluoroscopy. MATERIALS AND METHODS: An ionization chamber coupled with an electrometer was added to x-ray tube to measure the kerma area product with 65 kV and 0.7 mA technique, without and with additional filtration. Low contrast, gray scale and spatial resolution were measured utilizing Leeds test objects. Fifteen volunteers underwent pharynx study, ten without and five with aluminum and cooper filters associated, and had the kerma area product/minute compared. RESULTS: The specified filters addition, either separated or associated, allowed an expressive decrease in kerma area product besides an actual improvement in the

  17. Critical review of the safety assessment of nano-structured silica additives in food.

    Science.gov (United States)

    Winkler, Hans Christian; Suter, Mark; Naegeli, Hanspeter

    2016-06-10

    The development of nano-materials is viewed as one of the most important technological advances of the 21st century and new applications of nano-sized particles in the production, processing, packaging or storage of food are expected to emerge soon. This trend of growing commercialization of engineered nano-particles as part of modern diet will substantially increase oral exposure. Contrary to the proven benefits of nano-materials, however, possible adverse health effects have generally received less attention. This problem is very well illustrated by nano-structured synthetic amorphous silica (SAS), which is a common food additive since several decades although the relevant risk assessment has never been satisfactorily completed. A no observed adverse effect level of 2500 mg SAS particles/kg body weight per day was derived from the only available long-term administration study in rodents. However, extrapolation to a safe daily intake for humans is problematic due to limitations of this chronic animal study and knowledge gaps as to possible local intestinal effects of SAS particles, primarily on the gut-associated lymphoid system. This uncertainty is aggravated by digestion experiments indicating that dietary SAS particles preserve their nano-sized structure when reaching the intestinal lumen. An important aspect is whether food-borne particles like SAS alter the function of dendritic cells that, embedded in the intestinal mucosa, act as first-line sentinels of foreign materials. We conclude that nano-particles do not represent a completely new threat and that most potential risks can be assessed following procedures established for conventional chemical hazards. However, specific properties of food-borne nano-particles should be further examined and, for that purpose, in vitro tests with decision-making cells of the immune system are needed to complement existing in vivo studies.

  18. Study of the radiation dose reduction capability of a CT reconstruction algorithm: LCD performance assessment using mathematical model observers

    Science.gov (United States)

    Fan, Jiahua; Tseng, Hsin-Wu; Kupinski, Matthew; Cao, Guangzhi; Sainath, Paavana; Hsieh, Jiang

    2013-03-01

    Radiation dose on patient has become a major concern today for Computed Tomography (CT) imaging in clinical practice. Various hardware and algorithm solutions have been designed to reduce dose. Among them, iterative reconstruction (IR) has been widely expected to be an effective dose reduction approach for CT. However, there is no clear understanding on the exact amount of dose saving an IR approach can offer for various clinical applications. We know that quantitative image quality assessment should be task-based. This work applied mathematical model observers to study detectability performance of CT scan data reconstructed using an advanced IR approach as well as the conventional filtered back-projection (FBP) approach. The purpose of this work is to establish a practical and robust approach for CT IR detectability image quality evaluation and to assess the dose saving capability of the IR method under study. Low contrast (LC) objects imbedded in head size and body size phantoms were imaged multiple times with different dose levels. Independent signal present and absent pairs were generated for model observer study training and testing. Receiver Operating Characteristic (ROC) curves for location known exact and location ROC (LROC) curves for location unknown as well as their corresponding the area under the curve (AUC) values were calculated. Results showed approximately 3 times dose reduction has been achieved using the IR method under study.

  19. Assessment of the absorbed dose to organs from bone mineral density scan by using TLDS and the Monte Carlo method

    Directory of Open Access Journals (Sweden)

    Karimian Alireza

    2014-01-01

    Full Text Available Nowadays, dual energy X-ray absorptiometry is used in bone mineral density systems to assess the amount of osteoporosis. The purpose of this research is to evaluate patient organ doses from dual X-ray absorptiometry by thermoluminescence dosimeters chips and Monte Carlo method. To achieve this goal, in the first step, the surface dose of the cervix, kidney, abdomen region, and thyroid were measured by using TLD-GR 200 at various organ locations. Then, to evaluate the absorbed dose by simulation, the BMD system, patient's body, X-ray source and radiosensitive tissues were simulated by the Monte Carlo method. The results showed, for the spine (left femur bone mineral density scan by using thermoluminescence dosimeters, the absorbed doses of the cervix and kidney were 4.5 (5.64 and 162.17 (3.99(mGy, respectively. For spine (left femur bone mineral density scan in simulation, the absorbed doses of the cervix and kidney were 4.19 (5.88 and 175 (3.68(mGy, respectively. The data obtained showed that the absorbed dose of the kidney in the spine scan is noticeable. Furthermore, because of the small relative difference between the simulation and experimental results, the radiation absorbed dose may be assessed by simulation and software, especially for internal organs, and at different depths of otherwise inaccessible organs which is not possible in experiments.

  20. Structured Additive Quantile Regression for Assessing the Determinants of Childhood Anemia in Rwanda

    Directory of Open Access Journals (Sweden)

    Faustin Habyarimana

    2017-06-01

    Full Text Available Childhood anemia is among the most significant health problems faced by public health departments in developing countries. This study aims at assessing the determinants and possible spatial effects associated with childhood anemia in Rwanda. The 2014/2015 Rwanda Demographic and Health Survey (RDHS data was used. The analysis was done using the structured spatial additive quantile regression model. The findings of this study revealed that the child’s age; the duration of breastfeeding; gender of the child; the nutritional status of the child (whether underweight and/or wasting; whether the child had a fever; had a cough in the two weeks prior to the survey or not; whether the child received vitamin A supplementation in the six weeks before the survey or not; the household wealth index; literacy of the mother; mother’s anemia status; mother’s age at the birth are all significant factors associated with childhood anemia in Rwanda. Furthermore, significant structured spatial location effects on childhood anemia was found.

  1. Effects of a Cannabinoid1 receptor antagonist and Serotonin2C receptor agonist alone and in combination on motivation for palatable food: a dose-addition analysis study in mice.

    Science.gov (United States)

    Ward, Sara Jane; Lefever, Timothy W; Jackson, Cavario; Tallarida, Ronald J; Walker, Ellen A

    2008-05-01

    The cannabinoid and serotonin systems modulate feeding behavior in humans and laboratory animals. The present study assessed whether a cannabinoid (CB)(1) receptor antagonist and a serotonin (5-HT)(2C) receptor agonist alone and in combination attenuate motivation for the liquid nutritional drink Ensure as measured by a progressive ratio (PR) schedule of reinforcement in male C57BL/6 mice. Pretreatment (15 min i.p.) with either the CB(1) receptor antagonist N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboximide hydrochloride (SR141716) (SR; Rimonabant or Acomplia) or the 5-HT(2C) receptor agonist m-chlorophenylpiperazine (mCPP) dose-dependently decreased the maximum ratio completed under the PR schedule (break point) in mice. ED(25) values for SR and mCPP to decrease break point were determined, and the relative potency of each drug alone was quantified. Fixed dose-ratio pairs of SR/mCPP based on their relative potency were then administered. Dose-addition analysis comparing the experimentally determined potency for SR/mCPP combinations with their predicted additive potency revealed that SR/mCPP combinations in 1:1 and 2:1 ratios based on relative potency produced significant synergistic attenuation of break point for Ensure. The ED(25) values for decreasing break point were consistently lower than ED(25) values for decreasing response rate, and synergistic effects of SR/mCPP combinations on break point were seen independent of synergistic effects on response rate. These results indicate that cannabinoid CB(1) and serotonin 5-HT(2C) receptors are involved in motivated feeding behavior in mice and that these compounds can synergistically modulate motivation for palatable food with the synergy dependent upon the ratio of SR/mCPP in the combination.

  2. Assessment of fetal radiation dose to patients and staff in diagnostic radiology

    Energy Technology Data Exchange (ETDEWEB)

    Osei, E.K

    2000-07-01

    A major source of uncertainty in the estimation of fetal absorbed radiation dose is the influence of fetal size and position as these change with gestational age. Consequently, dose to the fetus is related to gestational age. Most studies of fetal dose estimation during pregnancy assume that the uterus dose is equal to fetal dose. These dose estimates do not take account of gestational age and individual fetal depth, factors which are significant when calculating dose. To establish both positional and size data for estimation of fetal absorbed dose from radiological examinations, the depths from the mother's anterior surface to the mid-line of the fetal head and abdomen were measured from ultrasound scans in 215 pregnant women. Depths were measured along a ray path projected in the anterior-posterior direction from the mother's abdomen. The fetal size was estimated from measurements of the fetal abdominal and head circumference, femur length and the biparietal diameter. The effects of fetal presentation, maternal bladder volume, placenta location, gestational age and maternal AP thickness on fetal depth and size were analysed. A Monte Carlo (MC) model was developed, and used to derive factors for converting dose-area product and free-in-air entrance surface dose from medical exposure of a pregnant patient to absorbed dose to the uterus/embryo, and for converting uterus dose to fetal dose in the later stages of pregnancy. Also presented are factors for converting thermoluminescence dosimeter reading from occupational exposure of a pregnant worker to equivalent dose to the fetus. The MC model was verified experimentally by direct measurement of uterus depth dose in a female Rando phantom, and also by comparison with other experimental work and MC results in the literature. The application of the various conversion factors is demonstrated by a review of the dose estimation process in 50 cases of fetal irradiation from medical exposures. (author)

  3. Reduction of radiation dose during the complex explorations using additional filter in pediatric patients; Reduccion de dosis en exploraciones complejas mediante el uso de filtracion adicional en pacientes pediatricos

    Energy Technology Data Exchange (ETDEWEB)

    Minguez, C.; Espana, M. L.; Castro, P.; Sevillano, D.; Lopez Franco, P.

    2006-07-01

    The aim of this study is to investigate the influence on image contrast, tube load and effective dose in paediatric fluoroscopy using added filtration. A Philips Omnidiagnosti is used in Nino Jesus Hospital and was therefore chosen for radiation dose measurements. The phantom consisted of varying methacrylate thickness to represent different patients sizes. All measurements were performed in automatic mode. For each exposure and additional filtration added the following data was recorded: tube voltage, tube current, air kerma rate on phantom surface and brightness on the image monitor. An 2026 electrometer (Radical Corporation) in conjunction with a model 2025-60 ion chamber were used for entrance dose measurements and the luxometer IL-400A (International Light) was used for brightness measurements on the image monitor: Evaluation of image quality was performed using a Leeds TOR TVF test object. Finally, the program PCXMC 1.5 based on the Monte Carlo method was used for calculating organ doses and the effective dose in fluoroscopy examinations. By increasing the filtration of the x-ray tube 1st Entrance radiation exposure can be decreased 58%, organ dose up to 40%, and effective dose up to 44%. 2nd The tube load increased up to 33%. 3rd Significant dose reduction is achievable without compromising image quality. The use of additional filtration in paediatric fluoroscopy should be evaluated taking into account dose reduction, additional tube loading and the possibility of some deterioration in image quality. (Author)

  4. Assessment of a low dose of IV midazolam used orally for conscious sedation in pediatric dentistry

    Directory of Open Access Journals (Sweden)

    M Mortazavi

    2009-08-01

    Full Text Available Background and the purpose of the study: Midazolam is preferably used in pediatric dentistry for quick onset of action and recovery. The aim of this prospective, observer-blind and placebo-controlled study was to assess the efficacy of a low dose of oral midazolam in modification of  the behavior of young pediatric dental patients. Methods: Forty children aged 3 to 5 years who displayed ratings 1 or 2 on the Frankl Scale and  were healthy by the American Society of Anesthesiologists-I status were randomly divided into two experimental and control groups of 20 each. All children required pulpotomy and restoration of D and E teeth and received either 0.25mg/kg of a 15mg/3ml IV midazolam mixed in black cherry syrup or the syrup alone. Subjects were continuously observed and monitored with pulse oximetry. Houpt's Behavioral Ratings was used to determine the overall behavior, the degree of crying and movement during treatment. Mann-Whitney U test was used for statistical analysis. Results and major conclusion: Patients who received 0.25mg/kg of the prepared oral midazolam significantly behaved better during treatment than the placebo controls (P<0.05. In comparison with the placebo group, reduced movement and crying were observed in the midazolam group (P<0.05. No adverse effects were observed and treatments were completed successfully. A low dose of 0.25mg/kg of a 15mg/3ml IV midazolam mixed in black cherry syrup was found to be effective in conscious sedation of young pediatric dental patients.

  5. Web-based training course for evaluating radiological dose assessment in NRC's license termination process.

    Science.gov (United States)

    Lepoire, D; Richmond, P; Cheng, J-J; Kamboj, S; Arnish, J; Chen, S Y; Barr, C; McKenney, C

    2008-08-01

    As part of the requirement for terminating the licenses of nuclear power plants or other nuclear facilities, license termination plans or decommissioning plans are submitted by the licensee to the U.S. Nuclear Regulatory Commission (NRC) for review and approval. Decommissioning plans generally refer to the decommissioning of nonreactor facilities, while license termination plans specifically refer to the decommissioning of nuclear reactor facilities. To provide a uniform and consistent review of dose modeling aspects of these plans and to address NRC-wide knowledge management issues, the NRC, in 2006, commissioned Argonne National Laboratory to develop a Web-based training course on reviewing radiological dose assessments for license termination. The course, which had first been developed in 2005 to target specific aspects of the review processes for license termination plans and decommissioning plans, evolved from a live classroom course into a Web-based training course in 2006. The objective of the Web-based training course is to train NRC staff members (who have various relevant job functions and are located at headquarters, regional offices, and site locations) to conduct an effective review of dose modeling in accordance with the latest NRC guidance, including NUREG-1757, Volumes 1 and 2. The exact size of the staff population who will receive the training has not yet been accurately determined but will depend on various factors such as the decommissioning activities at the NRC. This Web-based training course is designed to give NRC staff members modern, flexible access to training. To this end, the course is divided into 16 modules: 9 core modules that deal with basic topics, and 7 advanced modules that deal with complex issues or job-specific topics. The core and advanced modules are tailored to various NRC staff members with different job functions. The Web-based system uses the commercially available software Articulate, which incorporates audio, video

  6. Development and validation of a questionnaire to assess carbohydrate and insulin-dosing knowledge in youth with type 1 diabetes.

    Science.gov (United States)

    Koontz, Michaela B; Cuttler, Leona; Palmert, Mark R; O'Riordan, Maryann; Borawski, Elaine A; McConnell, Judy; Kern, Elizabeth O

    2010-03-01

    OBJECTIVE The American Diabetes Association advocates insulin regimens for youth with type 1 diabetes that involve adjusting insulin dose based on carbohydrate intake and blood glucose level. Implementing these regimens requires knowledge about carbohydrate content of foods and subsequent calculations of insulin dose, skills that may be difficult to gauge in practice. Therefore, we sought to develop and validate a questionnaire, the PedCarbQuiz (PCQ), to assess carbohydrate and insulin-dosing knowledge in youth with type 1 diabetes. RESEARCH DESIGN AND METHODS After development by an expert panel, the PCQ was administered to 75 youth with type 1 diabetes or their parents. Reliability was assessed by Cronbach alpha and split-half testing. To assess validity, scores were correlated with A1C, expert assessments, parent educational level, and complexity of insulin regimen. RESULTS PCQ mean score was 87 +/- 9.7% (range 42-98%). Cronbach alpha was 0.88, and correlation of split halves was 0.59 (P PCQ scores correlated significantly with lower A1C (r = -0.29, P = 0.01) and expert assessments (r = 0.56, P PCQ is a novel, easily administered instrument to assess knowledge about carbohydrates and insulin dosing calculations. Initial analyses support the reliability and validity of the PCQ.

  7. A method for independent modelling in support of regulatory review of dose assessments.

    Science.gov (United States)

    Dverstorp, Björn; Xu, Shulan

    2017-03-22

    Several countries consider geological disposal facilities as the preferred option for spent nuclear fuel due to their potential to provide isolation from the surface environment on very long timescales. In 2011 the Swedish Nuclear Fuel & Waste Management Co. (SKB) submitted a license application for construction of a spent nuclear fuel repository. The disposal method involves disposing spent fuel in copper canisters with a cast iron insert at about 500 m depth in crystalline basement rock, and each canister is surrounded by a buffer of swelling bentonite clay. SKB's license application is supported by a post-closure safety assessment, SR-Site. SR-Site has been reviewed by the Swedish Radiation Safety Authority (SSM) for five years. The main method for review of SKB's license application is document review, which is carried out by SSM's staff and supported by SSM's external experts. The review has proven a challenging task due to its broad scope, complexity and multidisciplinary nature. SSM and its predecessors have, for several decades, been developing independent models to support regulatory reviews of post-closure safety assessments for geological repositories. For the review of SR-Site, SSM has developed a modelling approach with a structured application of independent modelling activities, including replication modelling, use of alternative conceptual models and bounding calculations, to complement the traditional document review. This paper describes this scheme and its application to biosphere and dose assessment modelling. SSM's independent modelling has provided important insights regarding quality and reasonableness of SKB's rather complex biosphere modelling and has helped quantifying conservatisms and highlighting conceptual uncertainty. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Scoping assessment of radiological doses to aquatic organisms and wildlife -- N Springs

    Energy Technology Data Exchange (ETDEWEB)

    Poston, T.M.; Soldat, J.K.

    1992-10-01

    Estimated does rates were determined for endemic biota inhabiting the N Springs area based primarily on spring water data collected from the first 6 months of 1991. Radiological dose estimates were computed from measured values of specific radionuclides and modeled levels of radionuclides using established computer codes. The highest doses were predicted in hypothetical populations of clams, fish-eating ducks, and rabbits. The calculated dose estimates did not exceed 1 rad/d, an administrative dose rate established by the US Department of Energy for the protection of native aquatic biota. An administrative dose rate has not been established for terrestrial wildlife.

  9. Scoping assessment of radiological doses to aquatic organisms and wildlife -- N Springs. [N Springs

    Energy Technology Data Exchange (ETDEWEB)

    Poston, T.M.; Soldat, J.K.

    1992-10-01

    Estimated does rates were determined for endemic biota inhabiting the N Springs area based primarily on spring water data collected from the first 6 months of 1991. Radiological dose estimates were computed from measured values of specific radionuclides and modeled levels of radionuclides using established computer codes. The highest doses were predicted in hypothetical populations of clams, fish-eating ducks, and rabbits. The calculated dose estimates did not exceed 1 rad/d, an administrative dose rate established by the US Department of Energy for the protection of native aquatic biota. An administrative dose rate has not been established for terrestrial wildlife.

  10. Assessment of open source software for CBCT in detecting additional mental foramina

    Directory of Open Access Journals (Sweden)

    Oséas Santos Junior

    2013-04-01

    Full Text Available The purpose of this study was to evaluate which post-processing imaging protocol would be better to analyze the additional mental foramen (AMF in preoperative planning with cone-beam computed tomography (CBCT exams, and to test reproducibility of measurements, using open source software (OsiriX. The software was used to detect the cases of AMF from among 58 exams for dental implant planning in edentulous mandible areas-three cases were found. The case images were submitted to qualitative analysis using 2D orthogonal MPR, 3D-MPR and 3D volume rendering protocols by two oral and maxillofacial radiologists. Quantitative analysis used the 3D-MPR protocol; the closed polygon tool measured the mental foramen (MF and the AMF areas; the length tool measured the distance between foramina. The measurements were performed independently by the examiners, at two different times. Intra- and interexaminer agreement was assessed using the intraclass correlation coefficient. The panoramic view did not show the MF and the AMF clearly. The AMF could be detected in the parasagittal view. 2D Orthogonal MPR was effective to observe the AMF in some cases. The 3D-MPR and 3D view protocols were the most effective to locate and analyze the AMF. In conclusion, a 3D view improves visualization when anatomical points are not clearly visible. 3D-MPR was considered a more effective post-processing imaging protocol to observe foramina relationships. The high reproducibility of measurements for anatomical MF variations was established using specific tools featured in open source software for CBCT. OsiriX is realistic and recommended for preoperative planning.

  11. EXPOSURE DOSES ASSESSMENT OF POPULATION AT LONG-TERM PERIOD AFTER THE CHERNOBYL ACCIDENT: INTERNATIONAL COLLABORATION EXPERIENCE

    Directory of Open Access Journals (Sweden)

    N. G. Vlasova

    2013-01-01

    Full Text Available The study which had been conducted in the period from 1990 to 2000’s in the settlements ofGomelregion showed that the average internal exposure doses of population living in the settlements situated on territories with equal levels of contamination density were considerably different. The reasons for the difference have been revealed. It was shown that not only radiation contamination of territory but also a range of factors of non-radiation origin have influence on formation of internal exposure dose. The hypothesis has been approved that internal exposure dose of each individual and also of each family has its certain place, constant in time at a dose distribution curve. This appropriateness had been used as a methodological basis for reconstruction of subjects’ individual doses for any time period. Method for estimating the average annual effective exposure doses of inhabitants living in contaminated settlements of theBelarusRepublichad been developed. The results of the Whole Body Counter measurements had been used for direct assessment of internal exposure dose and as the basis for developing a model. Model for the dose estimation is based on the classification of settlements according to regional characteristics of soil, which cause 137Cs in taking with locally produced foodstuff. The model is also based on regression of daily 137Cs intake on the density contamination of the soil for each region. The effect of the indirect factors on the dose forming had been taken into account: the number of inhabitants and the area of forest around the settlement. According to the developed method, there had been created a Catalog of Average Annual Effective Doses of Residents of the Belarus Republic.

  12. Biosphere modelling for dose assessments of radioactive waste repositories. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Klos, R. [Paul Scherrer Inst., Wuerenlingen (Switzerland)] [and others

    1996-09-01

    The aims of the Complementary Studies Working Group were: to investigate and explain differences which exist between contemporary models with respect to how, for a given test case, they represent the modelled Features, Events and Processes (FEPs) and how the nature of these representations affects the calculational end-points; to determine the most appropriate ways of representing key FEPs; to identify where knowledge needs to be improved to give better representations of these key FEPs in the future and where simplifications of existing formulations might be possible; to show that the modelling undertaken is suitable for purpose, in that it is robust and that it is unlikely that the radiological consequences calculated by the models would be underestimated (so that any conservative bias in the models is justified); to build confidence in the available modelling tools; to extend the work undertaken in the first phase of BIOMOVS to include consideration of radiological dose. Ten modelling groups from Western Europe and Canada have participated, revealing a variety of representations of radionuclide transport processes and techniques for calculating dose. The exercise has focused on the ways in which key FEPs are represented with the intention of determining the robustness or otherwise of existing representations. This has been achieved by applying a well defined dataset representative of a Central European inland valley. Human habits and lifestyle are chosen to be representative of a subsistence agricultural community. Climatic conditions are those of the present day. Many of the conclusions have relevance beyond the immediate concerns of the Central European biospheres and, although care should be exercised when terms of reference differ greatly from the system detailed here, much has been learned which has wider applicability. The exercise has successfully compared not only the behaviour of biosphere models for waste disposal assessments, but has also provided the

  13. Dose assessment for sheep exposed to fallout from nuclear test Nancy

    Energy Technology Data Exchange (ETDEWEB)

    Sasser, L.B.; Soldat, J.K.; Kennedy, W.E. Jr.; Murphy, D.W.

    1982-10-01

    Radiation doses were estimated for sheep wintering on Nevada ranges during the testing at the Nevada Test Site of the nuclear weapon Nancy on March 24, 1953. Exposure pathways considered were inhalation of radionuclides from both cloud passage and resuspension, external exposure of the total body and skin, and ingestion of contaminated forage and soil. Physiological, metabolic, and dosimetric data needed for these calculations were obtained from data appropriate for the sheep. Dose rate and radionuclide deposition values for shot Nancy were used. Radionuclide deposition and retention on the desert vegetation were obtained from data collected during several nuclear tests at the Nevada Test Site. Existing dosimetric computer programs, whose libraries were modified to include the sheep data, and specially developed models were used to estimate the dose commitment for the sheep. The total-body dose for reference sheep located within the 40-mR/hr (H+12) isopleth from all modes of exposure was estimated to be 2.6 rad. Ingestion of fallout on edible vegetation contributed the majority of the dose, whereas inhalation of radionuclides and consumption of contaminated soil from the ground contributed little to the internal doses. The dose to the thyroid of ewes from radioiodine and other radionuclides reaching the thyroid was approximately 400 rad. The calculated uniform dose to the reticulo-rumen was 4 rad; however, if fallout particles were assumed to concentrate in the ventral rumen, a localized dose of 200 rad could have been received by the rumen wall. Estimated dose to the bare skin of ewes was 120 rad. The dose to the fetal thyroid from radioiodine ingested by a pregnant ewe grazing at a location where the dose rate was 40 mR/hr (H+12) was estimated to be 700 rad, or approximately twice the dose to the maternal thyroid.

  14. Is the Linear No-Threshold Dose-Response Paradigm Still Necessary for the Assessment of Health Effects of Low Dose Radiation?

    Science.gov (United States)

    Seong, Ki Moon; Seo, Songwon; Lee, Dalnim; Kim, Min-Jeong; Lee, Seung-Sook; Park, Sunhoo; Jin, Young Woo

    2016-02-01

    Inevitable human exposure to ionizing radiation from man-made sources has been increased with the proceeding of human civilization and consequently public concerns focus on the possible risk to human health. Moreover, Fukushima nuclear power plant accidents after the 2011 East-Japan earthquake and tsunami has brought the great fear and anxiety for the exposure of radiation at low levels, even much lower levels similar to natural background. Health effects of low dose radiation less than 100 mSv have been debated whether they are beneficial or detrimental because sample sizes were not large enough to allow epidemiological detection of excess effects and there was lack of consistency among the available experimental data. We have reviewed an extensive literature on the low dose radiation effects in both radiation biology and epidemiology, and highlighted some of the controversies therein. This article could provide a reasonable view of utilizing radiation for human life and responding to the public questions about radiation risk. In addition, it suggests the necessity of integrated studies of radiobiology and epidemiology at the national level in order to collect more systematic and profound information about health effects of low dose radiation.

  15. Influence of Al³⁺ addition on the flocculation and sedimentation of activated sludge: comparison of single and multiple dosing patterns.

    Science.gov (United States)

    Wen, Yue; Zheng, Wanlin; Yang, Yundi; Cao, Asheng; Zhou, Qi

    2015-05-15

    In this study, the flocculation and sedimentation performance of activated sludge (AS) with single and multiple dosing of trivalent aluminum (Al(3+)) were studied. The AS samples were cultivated in sequencing batch reactors at 22 °C. The dosages of Al(3+) were 0.00, 0.125, 0.5, 1.0, and 1.5 meq/L for single dosing, and 0.1 meq/L for multiple dosing. Under single dosing conditions, as Al(3+) dosage increased, the zeta potential, total interaction energy, and effluent turbidity decreased, whereas the sludge volume index (SVI) increased, indicating that single Al(3+) dosing could enhance sludge flocculation, but deteriorate sedimentation. By comparison, adding an equal amount of Al(3+) through multiple dosing achieved a similar reduction in turbidity, but the zeta potential was higher, while the loosely bound extracellular polymeric substances (LB-EPS) content and SVI remarkably declined. Although the difference in the flocculation performances between the two dosing patterns was not significant, the underlying mechanisms were quite distinct: the interaction energy played a more important role under single dosing conditions, whereas multiple dosing was more effective in reducing the EPS content. Multiple dosing, which allows sufficient time for sludge restructuring and floc aggregation, could simultaneously optimize sludge flocculation and sedimentation.

  16. Dose Assessment and Considerations When a Radioactive Seed is Unrecoverable in a Breast Surgical Patient.

    Science.gov (United States)

    Harvey, Richard P

    2016-11-01

    Excision of non-palpable breast tumors in cancer patients has been routinely performed using surgical clips and wires placed under mammographic or ultrasound guidance. An alternative method exists for performing these surgeries without surgical wires and this approach has become more widely used at Oncology Centers in the United States. Roswell Park Cancer Institute (RPCI) performs many of their breast surgeries with radioactive seeds and has enjoyed favorable outcomes along with an enhanced patient experience. There are some inherent difficulties with using radioactive seeds, and seed tracking can be a problem during surgical procedures. When a seed is misplaced, an extensive search is conducted in an effort to locate the misplaced seed. Every attempt to recover these radioactive seeds should be made unless patient safety is jeopardized. If the seed is unrecoverable, then a dose assessment must be performed and corrective action determined. It is important to have adequate policies and procedures in place to prevent these rare occurrences. They should be treated as a radioactive medical event.

  17. Radioactivity concentration variation with depth and assessment of workers' doses in selected mining sites

    Directory of Open Access Journals (Sweden)

    C.U. Nwankwo

    2015-04-01

    Full Text Available Mining workers are exposed to radiation in the process of extracting minerals from the earth crust. In this research, activity concentration of the radionuclides in samples collected at different depths in Komu (0–220 ft and Olode (0–30 ft mining sites, Oyo State, Nigeria and the associated workers' radiological risks were assessed. Gemstones from these sites are mined for local and international markets. The radionuclide contents of the samples were determined using Gamma spectroscopy technique. At Komu, 238U and 232Th concentrations, with few exceptions, increased with depth while that of 40K had no defined pattern. At Olode site, 238U and 232Th concentrations decreased with depth while that of 40K was almost constant. Internal hazard indices at Komu in some cases indicated an unacceptable level of risk to workers. Workers' doses would have been underestimated by between 12 and 55% if the activity concentrations of samples in the pit were not included in the calculation.

  18. Post-Remediation Radiological Dose Assessment, Linde Site, Tonawanda, New York

    Energy Technology Data Exchange (ETDEWEB)

    Kamboj, Sunita [Argonne National Lab. (ANL), Argonne, IL (United States); Durham, Lisa A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-06-01

    A post-remediation radiological dose assessment was conducted for the Formerly Utilized Sites Remedial Action Program (FUSRAP) Linde Site by using the measured residual concentrations of the radionuclides of concern following the completion of the soils remedial action. The site’s FUSRAP-related contaminants of concern (COCs) are radionuclides associated with uranium processing activities conducted by the Manhattan Engineer District (MED) in support of the Nation’s early atomic energy and weapons program and include radium-226 (Ra-226), thorium-230 (Th-230), and total uranium (Utotal). Remedial actions to address Linde Site soils and structures were conducted in accordance with the Record of Decision for the Linde Site, Tonawanda, New York (ROD) (USACE 2000a). In the ROD, the U.S. Army Corps of Engineers (USACE) determined that the cleanup standards found in Title 40, Part 192 of the Code of Federal Regulations (40 CFR Part 192), the standards for cleanup of uranium mill sites designated under the Uranium Mill Tailings Radiation Control Act (UMTRCA), and the Nuclear Regulatory Commission (NRC) standards for decommissioning of licensed uranium and thorium mills, found in 10 CFR Part 40, Appendix A, Criterion 6(6), are Applicable or Relevant and Appropriate Requirements (ARARs) for cleanup of MED-related contamination at the Linde Site. The major elements of this remedy will involve excavation of the soils with COCs above soil cleanup levels and placement of clean materials to meet the other criteria of 40 CFR Part 192.

  19. Assessment of safe bioactive doses of Foeniculum vulgare Mill. essential oil from Portugal.

    Science.gov (United States)

    Cabral, C; Miranda, M; Gonçalves, M J; Cavaleiro, C; Cruz, M T; Salgueiro, L

    2017-03-02

    This study was designed to evaluate the antifungal activity of Foeniculum vulgare essential oil; concomitantly, the safety of bioactive doses was also unveiled, for the first time, in several mammalian cells. The chemical characterisation was made by GC and GC-MS. Antifungal activity was evaluated against yeasts, dermatophytes and Aspergillus strains and germ tube inhibition assay was evaluated using Candida albicans. Cell viability was assessed by the MTT assay. The main constituents of the oil are E-anetol (47%), α-phellandrene (11%), α-pinene (10.1%) and fenchone (10.8%). The oil was more active against Cryptococcus neoformans and C. albicans (MICs 0.32-0.64 μL/mL) and the filamentation of C. albicans was totally inhibited with 0.08 μL/mL. The oil is safe for keratinocytes, hepatocytes and fibroblasts in concentrations up to 1.25 μL/mL, and to macrophages up to 0.64 μL/mL. These findings highlight safe bioactive concentrations that should be deeper investigated for further application in pharmaceutical industry.

  20. Proton Dose Assessment to the Human Eye Using Monte Carlo N-Particle Transport Code (MCNPX)

    Science.gov (United States)

    2006-08-01

    objective of this project was to develop a simple MCNPX model of the human eye to approximate dose delivered from proton therapy. The calculated dose...computer code MCNPX that approximates dose delivered during proton therapy. The calculations considered proton interactions and secondary interactions...Volume Calculation The MCNPX code has limited ability to compute the volumes of defined cells. The dosimetric volumes in the outer wall of the eye are

  1. DOSE-DEPENDENT EFFECT OF MOLYBDENUM ON PORCINE BLOOD CELLS: IN VITRO ASSESSMENT

    Directory of Open Access Journals (Sweden)

    Marcela Capcarová

    2013-10-01

    Full Text Available The aim of this study was to examine the effect of molybdenum (Mo on selected haematological parameters of porcine blood in vitro. The samples of blood were treated with an ammonium molybdate (NH46.Mo7O24.4H2O for 4 hours at 37oC in the concentrations 10, 100, and 1000 µg.ml-1 (E1, E2, and E3 group. Blood without Mo addition served as the control (C. Selected haematological parameters (WBC – total white blood cell count, LYM – lymphocyte count, GRA – granulocyte count, RBC – red blood cell count, HGB – haemoglobin, HCT – haematocrit and PLT – platelet count were measured using haematological analyser Abacus junior VET. Significant decrease in WBC, LYM, and GRA in the group with the highest dose of Mo (E3 against other groups (C, E1, and E2 was observed. Other results were not influenced by Mo exposure. Our results suggest that Mo can cause the changes and imbalance in immune system.

  2. {sup 226} Ra committed effective dose assessment for osteoporosis treatment with `Gran-White` dolomite

    Energy Technology Data Exchange (ETDEWEB)

    Pecequilo, Brigitte R.S.; Campos, Marcia P. de [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1997-12-01

    A total of 6 dolomite samples were prepared for activity concentration measurement by using high resolution gamma-ray spectrometry. The calculated average specific activity of {sup 226} Ra was 4.34 Bq/kg. The committed effective dose due to the Ra-226 specific activity in dolomite was performed following the ICRP 30 and ICRP 61 procedures and dose conversion factors. Values of 1.95 x 10{sup -6} Sv were obtained for committed effective dose and 5.93 x 10{sup -5} Sv for committed dose equivalent in the bone surface. (author). 9 refs., 2 tabs.

  3. Spot scanning proton therapy plan assessment: design and development of a dose verification application for use in routine clinical practice

    Science.gov (United States)

    Augustine, Kurt E.; Walsh, Timothy J.; Beltran, Chris J.; Stoker, Joshua B.; Mundy, Daniel W.; Parry, Mark D.; Bues, Martin; Fatyga, Mirek

    2016-04-01

    The use of radiation therapy for the treatment of cancer has been carried out clinically since the late 1800's. Early on however, it was discovered that a radiation dose sufficient to destroy cancer cells can also cause severe injury to surrounding healthy tissue. Radiation oncologists continually strive to find the perfect balance between a dose high enough to destroy the cancer and one that avoids damage to healthy organs. Spot scanning or "pencil beam" proton radiotherapy offers another option to improve on this. Unlike traditional photon therapy, proton beams stop in the target tissue, thus better sparing all organs beyond the targeted tumor. In addition, the beams are far narrower and thus can be more precisely "painted" onto the tumor, avoiding exposure to surrounding healthy tissue. To safely treat patients with proton beam radiotherapy, dose verification should be carried out for each plan prior to treatment. Proton dose verification systems are not currently commercially available so the Department of Radiation Oncology at the Mayo Clinic developed its own, called DOSeCHECK, which offers two distinct dose simulation methods: GPU-based Monte Carlo and CPU-based analytical. The three major components of the system include the web-based user interface, the Linux-based dose verification simulation engines, and the supporting services and components. The architecture integrates multiple applications, libraries, platforms, programming languages, and communication protocols and was successfully deployed in time for Mayo Clinic's first proton beam therapy patient. Having a simple, efficient application for dose verification greatly reduces staff workload and provides additional quality assurance, ultimately improving patient safety.

  4. Assessing the effects of different pectins addition on color quality and antioxidant properties of blackberry jam

    OpenAIRE

    Poiana, Mariana-Atena; Munteanu, Melania-Florina; Bordean, Despina-Maria; Gligor, Ramona; Alexa, Ersilia

    2013-01-01

    Background In the last years pectin and other hydrocolloids were tested for improving the color stability and the retention of bioactive compounds in gelled fruit-based products. In line with these concerns, our study has been directed to quantify the changes in antioxidant status and color indices of blackberry jam obtained with different types of pectin (degree of esterification: DE, degree of amidation: DA) and doses in response to processing and storage for 1, 3 and 6 months at 20°C. Resu...

  5. Extracting additional risk managers information from a risk assessment of Listeria monocytogenes in deli meats

    NARCIS (Netherlands)

    Pérez-Rodríguez, F.; Asselt, van E.D.; García-Gimeno, R.M.; Zurera, G.; Zwietering, M.H.

    2007-01-01

    The risk assessment study of Listeria monocytogenes in ready-to-eat foods conducted by the U.S. Food and Drug Administration is an example of an extensive quantitative microbiological risk assessment that could be used by risk analysts and other scientists to obtain information and by managers and s

  6. The Assessment Supplement: A Faculty-Designed Addition to NCC's Manual, "Concepts & Procedures for Academic Assessment." First Edition.

    Science.gov (United States)

    Nassau Community Coll., Garden City, NY.

    This document is the first in a series of annual, faculty-designed supplements to Nassau Community College's (NCC's) (New York) manual, "Concepts & Procedures for Academic Assessment." The supplements are intended to provide faculty a forum through which they can communicate assessment designs and the impacts of those designs on…

  7. Measurements of radioactivity and dose assessments in some building materials in Bitlis, Turkey.

    Science.gov (United States)

    Kayakökü, Halime; Karatepe, Şule; Doğru, Mahmut

    2016-09-01

    In this study, samples of perlite, pumice and Ahlat stones (Ignimbrite) extracted from mines in Bitlis and samples of other building materials produced in facilities in Bitlis were collected and analyzed. Activity concentrations of (226)Ra, (232)Th and (40)K in samples of building materials were measured using NaI detector (NaI(Tl)) with an efficiency of 24%. The radon measurements of building material samples were determined using CR-39 nuclear track detectors. (226)Ra, (232)Th and (40)K radioactivity concentrations ranged from (29.6±5.9 to 228.2±38.1Bq/kg), (10.8±5.4 to 95.5±26.1Bq/kg) and (249.3±124.7 to 2580.1±266.9Bq/kg), respectively. Radon concentration, radium equivalent activities, absorbed dose rate, excess lifetime cancer risk and the values of hazard indices were calculated for the measured samples to assess the radiation hazards arising from using those materials in the construction of dwellings. Radon concentration ranged between 89.2±12.0Bq/m(3) and 1141.0±225.0Bq/m(3). It was determined that Raeq values of samples conformed to world standards except for perlite and single samples of brick and Ahlat stone. Calculated values of absorbed dose rate ranged from 81.3±20.5 to 420.6±42.8nGy/h. ELCR values ranged from (1.8±0.3)×10(-3) to (9.0±1.0)×10(-3). All samples had ELCR values higher than the world average. The values of Hin and Hex varied from 0.35±0.11 to 1.78±0.18 and from 0.37±0.09 to 1.17±0.13, respectively. The results were compared with standard radioactivity values determined by international organizations and with similar studies. There would be a radiation risk for people living in buildings made of perlite, Ahlat-1 and Brick-3.

  8. Quality specifications for glucose meters: assessment by simulation modeling of errors in insulin dose.

    Science.gov (United States)

    Boyd, J C; Bruns, D E

    2001-02-01

    Proposed quality specifications for glucose meters allow results to be in error by 5-10% or more of the "true" concentration. Because meters are used as aids in the adjustment of insulin doses, we aimed to characterize the quantitative effect of meter error on the ability to identify the insulin dose appropriate for the true glucose concentration. Using Monte Carlo simulation, we generated random "true" glucose values within defined intervals. These values were converted to "measured" glucose values using mathematical models of glucose meters having defined imprecision (CV) and bias. For each combination of bias and imprecision, 10,000-20,000 true and measured glucose concentrations were matched with the corresponding insulin doses specified by selected insulin-dosing regimens. Discrepancies in prescribed doses were counted and their frequencies plotted in relation to bias and imprecision. For meters with a total analytical error of 5%, dosage errors occurred in approximately 8-23% of insulin doses. At 10% total error, 16-45% of doses were in error. Large errors of insulin dose (two-step or greater) occurred >5% of the time when the CV and/or bias exceeded 10-15%. Total dosage error rates were affected only slightly by choices of sliding scale among insulin dosage rules or by the range of blood glucose. To provide the intended insulin dosage 95% of the time required that both the bias and the CV of the glucose meter be <1% or <2%, depending on mean glucose concentrations and the rules for insulin dosing. Glucose meters that meet current quality specifications allow a large fraction of administered insulin doses to differ from the intended doses. The effects of such dosage errors on blood glucose and on patient outcomes require study.

  9. Nonmonotonic Dose Responses as They Apply to Estrogen, Androgen, and Thyroid Pathways and EPA Testing and Assessment Procedures

    Science.gov (United States)

    A state of the science document providing a judgment on the degree to which nonmonotonic dose-responses are evidenced in the scientific literature and to evaluate the extent to which they may impact U.S. EPA’s chemical testing and risk assessment.

  10. Assessment of CT dose to the fetus and pregnant female patient using patient-specific computational models

    DEFF Research Database (Denmark)

    Xie, Tianwu; Poletti, Pierre-Alexandre; Platon, Alexandra

    2017-01-01

    PURPOSE: This work provides detailed estimates of the foetal dose from diagnostic CT imaging of pregnant patients to enable the assessment of the diagnostic benefits considering the associated radiation risks. MATERIALS AND METHODS: To produce realistic biological and physical representations of ...

  11. Progress in Assessing Air Pollutant Risks from In Vitro Exposures: Matching Ozone Dose and Effect in Human Air Way Cells

    Science.gov (United States)

    In vitro exposures to air pollutants could, in theory, facilitate a rapid and detailed assessment of molecular mechanisms of toxicity. However, it is difficult to ensure that the dose of a gaseous pollutant to cells in tissue culture is similar to that of the same cells during in...

  12. Avoiding Pitfalls in the Use of the Benchmark Dose Approach to Chemical Risk Assessments; Some Illustrative Case Studies (Presentation)

    Science.gov (United States)

    The USEPA's benchmark dose software (BMDS) version 1.2 has been available over the Internet since April, 2000 (epa.gov/ncea/bmds.htm), and has already been used in risk assessments of some significant environmental pollutants (e.g., diesel exhaust, dichloropropene, hexachlorocycl...

  13. Benchmark Dose Analysis from Multiple Datasets: The Cumulative Risk Assessment for the N-Methyl Carbamate Pesticides

    Science.gov (United States)

    The US EPA’s N-Methyl Carbamate (NMC) Cumulative Risk assessment was based on the effect on acetylcholine esterase (AChE) activity of exposure to 10 NMC pesticides through dietary, drinking water, and residential exposures, assuming the effects of joint exposure to NMCs is dose-...

  14. A Technical Approach to Expedited Processing of NTPR Radiation Dose Assessments

    Science.gov (United States)

    2011-10-01

    Dose Cohort .............................................................................. 87 B-2 Treatment of Exclusions...magnitude given the same scenario of exposure. • Uniformity in the treatment of upper-bound doses is maintained. • Approved NTPR standard methods...Pharynx (140-149) TONSILS TONSILS Tonsils ET Region+ Surrogate Oral Cavity and Pharynx (140-149) TRACHEA TRACHEA Trachea Lung Surrogate Lung (162

  15. Premature chromosome condensation (PCC) assay for dose assessment in mass casualty accidents.

    Science.gov (United States)

    Lindholm, Carita; Stricklin, Daniela; Jaworska, Alicja; Koivistoinen, Armi; Paile, Wendla; Arvidsson, Eva; Deperas-Standylo, Joanna; Wojcik, Andrzej

    2010-01-01

    The study was undertaken to establish a dose calibration curve for a practical PCC ring assay and to apply it in a simulated mass casualty accident. The PCC assay was validated against the conventional dicentric assay. A linear relationship was established for PCC rings after (60)Co gamma irradiation with doses up to 20 Gy. In the simulated accident experiment, 62 blood samples were analyzed with both the PCC ring assay and the conventional dicentric assay, applying a triage approach. Samples received various uniform and non-uniform (10-40% partial-body) irradiations up to doses of 13 Gy. The results indicated that both assays yielded good dose estimates for the whole-body exposure scenario, although in the lower-dose range (0-6 Gy) dicentric scoring resulted in more accurate whole-body estimates, whereas PCC rings were better in the high-dose range (>6 Gy). Neither assay was successful in identifying partial-body exposures, most likely due to the low numbers of cells scored in the triage mode. In conclusion, the study confirmed that the PCC ring assay is suitable for use as a biodosimeter after whole-body exposure to high doses of radiation. However, there are limitations for its use in the triage of people exposed to high, partial-body doses.

  16. The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation

    Science.gov (United States)

    Van Dongen, Hans P A.; Maislin, Greg; Mullington, Janet M.; Dinges, David F.

    2003-01-01

    OBJECTIVES: To inform the debate over whether human sleep can be chronically reduced without consequences, we conducted a dose-response chronic sleep restriction experiment in which waking neurobehavioral and sleep physiological functions were monitored and compared to those for total sleep deprivation. DESIGN: The chronic sleep restriction experiment involved randomization to one of three sleep doses (4 h, 6 h, or 8 h time in bed per night), which were maintained for 14 consecutive days. The total sleep deprivation experiment involved 3 nights without sleep (0 h time in bed). Each study also involved 3 baseline (pre-deprivation) days and 3 recovery days. SETTING: Both experiments were conducted under standardized laboratory conditions with continuous behavioral, physiological and medical monitoring. PARTICIPANTS: A total of n = 48 healthy adults (ages 21-38) participated in the experiments. INTERVENTIONS: Noctumal sleep periods were restricted to 8 h, 6 h or 4 h per day for 14 days, or to 0 h for 3 days. All other sleep was prohibited. RESULTS: Chronic restriction of sleep periods to 4 h or 6 h per night over 14 consecutive days resulted in significant cumulative, dose-dependent deficits in cognitive performance on all tasks. Subjective sleepiness ratings showed an acute response to sleep restriction but only small further increases on subsequent days, and did not significantly differentiate the 6 h and 4 h conditions. Polysomnographic variables and delta power in the non-REM sleep EEG-a putative marker of sleep homeostasis--displayed an acute response to sleep restriction with negligible further changes across the 14 restricted nights. Comparison of chronic sleep restriction to total sleep deprivation showed that the latter resulted in disproportionately large waking neurobehavioral and sleep delta power responses relative to how much sleep was lost. A statistical model revealed that, regardless of the mode of sleep deprivation, lapses in behavioral alertness

  17. Life Cycle Assessment of Functionally Enhanced Polymers-Engineered Nanomaterials or Conventional Additives?

    DEFF Research Database (Denmark)

    Miseljic, Mirko; Olsen, Stig Irving

    2016-01-01

    Engineered nanomaterials, where at least one dimension is within 1-100 nm, are produced and used in many consumer products, with the purpose of enhancing specific material properties (e. g., in plastic products). Conventionally, organic and inorganic non-engineered nanomaterial additives are also...... insulation panels for buildings). Antibacterial, ultraviolet ray protection or flame retardancy properties of these products have been improved through the addition of either Ag, ZnO or Mg(OH)(2) engineered nanomaterials, or conventional organic/inorganic polymer additives. The study also presents new...... that in all cases the products with engineered nanomaterials generate higher potential environmental impacts than products with conventional additives. However, when considering the improved material functionality results differ more. The polyvinylchloride-wood outdoor flooring and polystyrene insulation...

  18. Biosphere modelling for dose assessments of radioactive waste repositories. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Klos, R. [Paul Scherrer Inst., Wuerenlingen (Switzerland)] [and others

    1996-09-01

    The aims of the Complementary Studies Working Group were: to investigate and explain differences which exist between contemporary models with respect to how, for a given test case, they represent the modelled Features, Events and Processes (FEPs) and how the nature of these representations affects the calculational end-points; to determine the most appropriate ways of representing key FEPs; to identify where knowledge needs to be improved to give better representations of these key FEPs in the future and where simplifications of existing formulations might be possible; to show that the modelling undertaken is suitable for purpose, in that it is robust and that it is unlikely that the radiological consequences calculated by the models would be underestimated (so that any conservative bias in the models is justified); to build confidence in the available modelling tools; to extend the work undertaken in the first phase of BIOMOVS to include consideration of radiological dose. Ten modelling groups from Western Europe and Canada have participated, revealing a variety of representations of radionuclide transport processes and techniques for calculating dose. The exercise has focused on the ways in which key FEPs are represented with the intention of determining the robustness or otherwise of existing representations. This has been achieved by applying a well defined dataset representative of a Central European inland valley. Human habits and lifestyle are chosen to be representative of a subsistence agricultural community. Climatic conditions are those of the present day. Many of the conclusions have relevance beyond the immediate concerns of the Central European biospheres and, although care should be exercised when terms of reference differ greatly from the system detailed here, much has been learned which has wider applicability. The exercise has successfully compared not only the behaviour of biosphere models for waste disposal assessments, but has also provided the

  19. Evaluation of low-dose dual energy computed tomography for in vivo assessment of renal/ureteric calculus composition.

    Science.gov (United States)

    Mahalingam, Harshavardhan; Lal, Anupam; Mandal, Arup K; Singh, Shrawan Kumar; Bhattacharyya, Shalmoli; Khandelwal, Niranjan

    2015-08-01

    This study aimed to assess the accuracy of low-dose dual-energy computed tomography (DECT) in predicting the composition of urinary calculi. A total of 52 patients with urinary calculi were scanned with a 128-slice dual-source DECT scanner by use of a low-dose protocol. Dual-energy (DE) ratio, weighted average Hounsfield unit (HU) of calculi, radiation dose, and image noise levels were recorded. Two radiologists independently rated study quality. Stone composition was assessed after extraction by Fourier transform infrared spectroscopy (FTIRS). Analysis of variance was used to determine if the differences in HU values and DE ratios between the various calculus groups were significant. Threshold cutoff values to classify the calculi into separate groups were identified by receiver operating characteristic curve analysis. A total of 137 calculi were detected. FTIRS analysis differentiated the calculi into five groups: uric acid (n=17), struvite (n=3), calcium oxalate monohydrate and dihydrate (COM-COD, n=84), calcium oxalate monohydrate (COM, n=28), and carbonate apatite (n=5). The HU value could differentiate only uric acid calculi from calcified calculi (p80% sensitivity and specificity to differentiate them. The DE ratio could not differentiate COM from COM-COD calculi. No study was rated poor in quality by either of the observers. The mean radiation dose was 1.8 mSv. Low-dose DECT accurately predicts urinary calculus composition in vivo while simultaneously reducing radiation exposure without compromising study quality.

  20. Biomarkers of internal dose for the assessment of environmental exposure to benzene.

    Science.gov (United States)

    Lovreglio, Piero; D'Errico, Maria Nicolà; Fustinoni, Silvia; Drago, Ignazio; Barbieri, Anna; Sabatini, Laura; Carrieri, Mariella; Apostoli, Pietro; Soleo, Leonardo

    2011-10-01

    The urinary excretion of t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (SPMA) and urinary benzene and the influence of a smoking habit and of exposure to urban traffic on the urinary excretion of these biomarkers were investigated in 137 male adults from the general population. All subjects were not occupationally exposed to benzene and resident in two cities in Puglia (Southern-Italy). Environmental exposure to benzene was measured using passive personal samplers. The biomarkers t,t-MA, SPMA and urinary benzene were determined in urine samples collected from each subject at the end of the environmental sampling. The percentage of cases above the limit of detection was higher for SPMA and urinary benzene in smokers than in non-smokers, and for airborne benzene and urinary benzene in subjects exposed to urban traffic. Airborne benzene was correlated with the time spent in urban traffic during the environmental sampling. Among the biomarkers, urinary benzene was found to be correlated with airborne benzene only in non-smokers, and with the time spent in urban traffic, both in smokers and non-smokers considered together, and in non-smokers only. Finally, multiple regression analysis showed that the urinary excretion of all the biomarkers was dependent on the number of cigarettes smoked per day and, for urinary benzene, also on the time spent in urban traffic. In conclusion, urinary benzene seems to be a more valid biomarker than t,t-MA and SPMA to assess environmental exposure to extremely low concentrations of benzene. Cigarette smoking prevailed over traffic exhaust fumes in determining the internal dose of benzene.

  1. Radionuclides in Animal Feed (Poultry) 'Assessment of Radiation Dose'

    Energy Technology Data Exchange (ETDEWEB)

    Algadi, S.; Salih, I. [Radiation Safety Institute (Sudan)

    2014-07-01

    In this work a comprehensive study has been carried out for the determination of presents evaluation of effective dose due to consumption of chicken fed by fodders collected from four major Sudanese companies (Hader, Koudjs, Wifi and Preconex SPN.V). The concentrations of radionuclides in the thirty two (32) feed samples have been determined by gamma spectrometry using NaI(Tl) detector. Radionuclides observed were: Pb-212 (daughter of Th-238), Pb-214, Bi-214 (daughters of U-238), Cs-137 and K-40 concentration. In additives the activity concentration of these radionuclides has found in the following ranges: 0.81 - 22.06 Bq/kg, 0.59 - 32.07 Bq/kg, 0.64 - 15.77 Bq/kg, 0.01 - 2.02 Bq/kg and 33.58 - 204.61 Bq/kg respectively. In feed concentrates activity concentration ranges has: 0.73 - 13.79 Bq/kg, 0.33 - 20.04 Bq/kg, 0.01 - 1.67 Bq/kg, 0.01 - 0.28 Bq/kg, 26.86 - 99.21 Bq/kg respectively. In fodders the activity concentration ranges has: 1.25 - 1.52 Bq/kg, 0.12 - 1.24 Bq/kg, 0.51 - 1.25 Bq/kg, 0.01 - 0.61 Bq/kg, 11.94 - 127.88 Bq/kg respectively. The 'animal product' activity concentration ranges has: 0.31 - 1.65 Bq/kg, 0.22 - 1.11 Bq/kg, 0.26 - 1.07 Bq/kg, 0.03 - 0.51 Bq/kg, 14.07 - 79.93 Bq/kg respectively. High concentrations (233.3 Bq/Kg) has typically found in toxo(additive); the lowest concentration (27.9 Bq/Kg ) has found in concentrate for layers and animal product. The total average effective dose due to the different feed-stuff has estimated and found to be 5.89x10{sup -6}±3.11x10{sup -6}mSv/y and 13.9 x 10{sup -7} ± 7.24 x 10{sup -7}mSv/y for age categories 7-12 y and >17 y respectively. If compared with the limits - Radioactivity Levels Permitted in foodstuffs Part 1 the Saudi Standards, Metrology and quality (300 Bq/Kg) and ICRP,FAO organization (5 mSv/y) - these values are very low. Document available in abstract form only. (authors)

  2. Assessment of a twice dosing regimen both before and after partial hepatectomy in the rat liver micronucleus test.

    Science.gov (United States)

    Itoh, Satoru; Igarashi, Miyuki; Nagata, Mayumi; Hattori, Chiharu

    2015-04-01

    The liver micronucleus test is an important method to detect in vivo genotoxicants, especially those that require metabolic activation for their genotoxicity. We have already reported that structural or numerical chromosome aberration inducers have to be given before or after partial hepatectomy, respectively, to detect their genotoxicity in the liver of rats. In the present study, we assessed a twice dosing regimen, in which the genotoxicant is dosed both before and after partial hepatectomy, using the four chromosome aberration inducers used in the previous study. Two structural chromosome aberration inducers (diethylnitrosamine and 1,2-dimethylhydrazine) and two numerical chromosome aberration inducers (colchicine and carbendazim) were used. The genotoxicant was administered to 8-week old male F344 rats one day before and again one day after the partial hepatectomy and hepatocytes were isolated 3 days after second dosing (4 days after the partial hepatectomy). As a result, all genotoxicants (structural or numerical chromosome aberration inducers) caused a dose-dependent statistically significant increase in the incidence of micronucleated hepatocytes when given both before and after partial hepatectomy. No marked difference was observed in general toxicity, relative liver weight and cell classification between single dosing regimens and twice dosing regimen of the genotoxicants. These results confirm that the twice dosing regimen, in which the test compound is dosed both before and after partial hepatectomy, can detect in vivo induction of micronucleated hepatocytes by structural or numerical chromosome aberration inducers qualitatively similar to their appropriate regimen in which the test compound is administered either before or after partial hepatectomy.

  3. Assessment of Environmental Gamma Radiation Dose Rate in Ardabil and Sarein in 2009

    Directory of Open Access Journals (Sweden)

    M Alighadri

    2011-10-01

    Full Text Available Background and Objectives: Gamma rays, the most energetic photons within the any other wave in the electromagnetic spectrum, pose enough energy to form charged particles and adversely affect human health. Provided that the external exposure of human beings to natural environmental gamma radiation normally exceeds that from all man-made sources combined, environmental gamma dose rate and corresponding annual effective dose were determined in the cities of Ardabil and Sar Ein.Materials and Methods: Outdoor environmental gamma dose rates were measured using an Ion Chamber Survey Meter in 48 selected locations (one in city center and the remaining in cardinal and ordinal directions in Ardabil and Sar Ein. Ten more locations were monitored along the hot springs effluent in Sar Ein. Measurements of gamma radiation dose rate were performed at 20 and 100 cm above the ground for a period of one hour.Results: Average outdoor environmental gamma dose rate were determined as 265, 219, and 208  for Ardabil, Sar Ein, and along the hot spring effluent, respectively. The annual affective dose for Ardabil and Sar Ein residents were estimated to be 1.45 and 1.39 mSv, respectively.Conclusion: Calculated annual effective dose of 1.49 and 1.35 are appreciably higher than the population weighted average exposure to environmental gamma radiation worldwide and that analysis of soil content to different radionuclide is suggested.

  4. Electro-acupuncture reduces the need for additional anesthetics in experimental studies Eletroacupuntura reduz a necessidade de doses adicionais de anestésicos em estudos experimentais

    Directory of Open Access Journals (Sweden)

    Agamenon Honório Silva

    2010-08-01

    Full Text Available PURPOSE: To evaluate the possible beneficial effects of electro-acupuncture in rats subjected to ketamine/xylazine (KX intra-peritoneal (i.p. anesthesia. METHODS: Forty-eight male Wistar rats were distributed in four equal groups. All rats received i.p. injections of ketamine (90 mg/kg +xylazine (10 mg/kg anesthesia. Basal values group (control rats (BV received no additional treatment. The equivalent of the human right ST36 (Zusanli and CV-12(Zhongwan acupoints were chosen for needling and electrical stimulation. AC rats were needled with sterilized disposable stainless steel needles at right ST36 and CV12 acupoints; needles were retained for 30 minutes. EAC10 rats, after needle insertion as described, had electrodes connected to both needles and to an electro stimulator model NKL EL-608; pulsed square waves, 10 Hz, 10 mA, was applied for 30 minutes. EAC100 rats were submitted to EA as described. However, a greater frequency (100 Hz was used. RESULTS: Thirty-seven rats remained under adequate anesthetic level during the experiment. However, maintenance anesthesia was required by 11 rats. Need for additional anesthesia decreased to 9.1% in EAC100 rats compared to BV (36.3%. CONCLUSION: Both the AC and the EAC10/100 prolong the anesthetic effect of the combination Ketamine-xylazine in rats, allowing longer duration of anesthesia with a lower dose of anesthetic, thereby reducing the occurrence of complications.OBJETIVO: Avaliar os possíveis efeitos benéficos da eletroacupuntura em ratos submetidos à anestesia intraperitoneal (i.p. com ketamina / xilazina. MÉTODOS: Quarenta e oito ratos Wistar foram randomizados em quatro grupos iguais. Todos os ratos receberam injeções i.p. de ketamina (90 mg / kg + xilazina (10 mg / kg. Os ratos do grupo Valores Basais (controle - BV não receberam nenhum tratamento adicional. Os acupontos equivalentes aos humanos E-36 (Zusanli e VC-12 (Zhongwan foram escolhidos para inserção de agulhas e estimulação el

  5. Dose Assessment in Computed Tomography Examination and Establishment of Local Diagnostic Reference Levels in Mazandaran, Iran

    Directory of Open Access Journals (Sweden)

    Janbabanezhad Toori A.

    2015-12-01

    Full Text Available Background: Medical X-rays are the largest man-made source of public exposure to ionizing radiation. While the benefits of Computed Tomography (CT are well known in accurate diagnosis, those benefits are not risk-free. CT is a device with higher patient dose in comparison with other conventional radiation procedures. Objective: This study is aimed at evaluating radiation dose to patients from Computed Tomography (CT examination in Mazandaran hospitals and defining diagnostic reference level (DRL. Methods: Patient-related data on CT protocol for four common CT examinations including brain, sinus, chest and abdomen & pelvic were collected. In each center, Computed Tomography Dose Index (CTDI measurements were performed using pencil ionization chamber and CT dosimetry phantom according to AAPM report No. 96 for those techniques. Then, Weighted Computed Tomography Dose Index (CTDIW, Volume Computed Tomography Dose Index (CTDI vol and Dose Length Product (DLP were calculated. Results: The CTDIw for brain, sinus, chest and abdomen & pelvic ranged (15.6- 73, (3.8-25. 8, (4.5-16.3 and (7-16.3, respectively. Values of DLP had a range of (197.4-981, (41.8-184, (131-342.3 and (283.6-486 for brain, sinus, chest and abdomen & pelvic, respectively. The 3rd quartile of CTDIW, derived from dose distribution for each examination is the proposed quantity for DRL. The DRLs of brain, sinus, chest and abdomen & pelvic are measured 59.5, 17, 7.8 and 11 mGy, respectively. Conclusion: Results of this study demonstrated large scales of dose for the same examination among different centers. For all examinations, our values were lower than international reference doses.

  6. Effect of Total Dose of Lidocaine on Duration of Adductor Canal Block, Assessed by Different Test Methods

    DEFF Research Database (Denmark)

    Jæger, Pia; Koscielniak-Nielsen, Zbigniew J; Hilsted, Karen Lisa

    2016-01-01

    BACKGROUND: The binary aims of this study were to investigate the effect of total dose of lidocaine on duration of an adductor canal block (ACB) and to validate different methods used to assess nerve blocks. METHODS: We performed 2 blinded, randomized, controlled crossover trials, including healthy......, young men. In study 1, 14 subjects received 4 ACBs with saline and 40, 80, and 160 mg lidocaine. In study 2, 14 new subjects received 2 ACBs with 100 and 300 mg lidocaine. We kept volume constant at 20 mL for all blocks, only altering concentration. ACB duration was assessed every hour postblock using......: In study 1, block duration assessed by mechanical discrimination differed significantly when comparing the 40-mg dose with the 80-mg dose (mean difference, 1.15 hours; 99% confidence interval [CI], 0.38–2.09 hours) and with the 160-mg dose (mean difference, 0.92 ours; 99% CI, 0.17–1.62). However...

  7. A biosphere modeling methodology for dose assessments of the potential Yucca Mountain deep geological high level radioactive waste repository.

    Science.gov (United States)

    Watkins, B M; Smith, G M; Little, R H; Kessler, J

    1999-04-01

    Recent developments in performance standards for proposed high level radioactive waste disposal at Yucca Mountain suggest that health risk or dose rate limits will likely be part of future standards. Approaches to the development of biosphere modeling and dose assessments for Yucca Mountain have been relatively lacking in previous performance assessments due to the absence of such a requirement. This paper describes a practical methodology used to develop a biosphere model appropriate for calculating doses from use of well water by hypothetical individuals due to discharges of contaminated groundwater into a deep well. The biosphere model methodology, developed in parallel with the BIOMOVS II international study, allows a transparent recording of the decisions at each step, from the specification of the biosphere assessment context through to model development and analysis of results. A list of features, events, and processes relevant to Yucca Mountain was recorded and an interaction matrix developed to help identify relationships between them. Special consideration was given to critical/potential exposure group issues and approaches. The conceptual model of the biosphere system was then developed, based on the interaction matrix, to show how radionuclides migrate and accumulate in the biosphere media and result in potential exposure pathways. A mathematical dose assessment model was specified using the flexible AMBER software application, which allows users to construct their own compartment models. The starting point for the biosphere calculations was a unit flux of each radionuclide from the groundwater in the geosphere into the drinking water in the well. For each of the 26 radionuclides considered, the most significant exposure pathways for hypothetical individuals were identified. For 14 of the radionuclides, the primary exposure pathways were identified as consumption of various crops and animal products following assumed agricultural use of the contaminated

  8. The additive prognostic value of perfusion and functional data assessed by quantitative gated SPECT in women

    NARCIS (Netherlands)

    Y.G.C.J. America (Yves); J.J. Bax (Jeroen); H. Boersma (Eric); M. Stokkel (Marcel); E.E. van der Wall (Ernst)

    2009-01-01

    textabstractBackground: The aim of this study was to assess the prognostic value of technetium-99m tetrofosmin gated SPECT imaging in women using quantitative gated single photon emission computed tomography (SPECT) imaging. Methods: We followed 453 consecutive female patients. Average follow-up was

  9. DOSES ASSESSMENT OF POPULATION AT LONG-TERM PERIOD AFTER THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    N. G. Vlasova

    2014-01-01

    Full Text Available Republiccontaminated settlements had been developed. The results of the Whole Body measurements had been used as the basis for the model developing. The model for dose estimation is based on the classification of the settlements according to regional characteristics of soils, which cause 137Cs intake with locally produced foodstuff. The model is also based on regression of internal exposure dose on the soil surface activity for each region. The influence of the indirect factors on the dose forming had been taken into account: the number of inhabitants and the area of forest around the settlement. According  to  the  developed  method,  Catalog  of  Average  Annual  Effective  Doses  for  Residents  of  the Belarus Republic had been created.

  10. Personal radiation monitoring and assessment of doses received by radiation workers (1996)

    Energy Technology Data Exchange (ETDEWEB)

    Morris, N.D.

    1996-12-01

    Since late 1986, all persons monitored by the Australian Radiation Laboratory have been registered on a data base which maintains records of the doses received by each individual wearer. At present, the Service regularly monitors approximately 30,000 persons, which is roughly 90 percent of those monitored in Australia, and maintains dose histories of over 75,000 people. The skin dose for occupationally exposed workers can be measured by using one of the five types of monitor issued by the Service: Thermoluminescent Dosemeter (TLD monitor), Finger TLD 3, Neutron Monitor, Special TLD and Environmental monitor. The technical description of the monitors is provided along with the method for calculating the radiation dose. 5 refs., 7 tabs., 5 figs.

  11. Exposure Scenarios and Unit Dose Factors for the Hanford Immobilized Low Activity Tank Waste Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    RITTMANN, P.D.

    1999-12-29

    Exposure scenarios are defined to identify potential pathways and combinations of pathways that could lead to radiation exposure from immobilized tank waste. Appropriate data and models are selected to permit calculation of dose factors for each exposure

  12. Assessment of Pulmonary Toxicity Induced by Inhaled Toner with External Additives

    Directory of Open Access Journals (Sweden)

    Taisuke Tomonaga

    2017-01-01

    Full Text Available We investigated the harmful effects of exposure to a toner with external additives by a long-term inhalation study using rats, examining pulmonary inflammation, oxidative stress, and histopathological changes in the lung. Wistar rats were exposed to a well-dispersed toner (mean of MMAD: 2.1 μm at three mass concentrations of 1, 4, and 16 mg/m3 for 22.5 months, and the rats were sacrificed after 6 months, 12 months, and 22.5 months of exposure. The low and medium concentrations did not induce statistically significant pulmonary inflammation, but the high concentration did, and, in addition, a histopathological examination showed fibrosis in the lung. Although lung tumor was observed in one sample of high exposure for 22.5 months, the cause was not statistically significant. On the other hand, a persistent increase in 8-OHdG was observed in the high exposure group, indicating that DNA damage by oxidative stress with persistent inflammation leads to the formation of tumorigenesis. The results of our studies show that toners with external additives lead to pulmonary inflammation, oxidative stress, and fibrosis only at lung burdens beyond overload. These data suggest that toners with external additives may have low toxicity in the lung.

  13. An Assessment of Spinal Cord Dose Following Radiotherapy of Nasopharyngeal Cancer by TLD and Rando Phantom

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Bahreyni Toossi

    2009-12-01

    Full Text Available Introduction: Nasopharyngeal carcinoma is one of the most common malignancies in the head and neck region and radiotherapy is its treatment of choice. In spite of the fact that it is widely used, due to the presence of many sensitive organs or tissues in this region, patients may suffer from a wide range of side effects. One such sensitive tissue is the spinal cord. If the absorbed dose to spinal cord is greater than its tolerance dose, then myelopathy and Lhermitte’s sign are not avoidable. Material and Methods: Thehead and neck of a Rando phantom (reference man was employed as a hypothetical patient suffering from nasopharyngeal carcinoma. The full course of treatment consisted of three phases. At the beginning of every phase, an oncologist used a simulator to delineate the surface of the Rando Phantom for treatment. TLD chips (TLD-100 were employed for dose measurement. TLD chips were inserted in the previously made holes on the surface of selected slices adjacent to second cervical to fourth thoracic vertebra. Absorbed dose by TLDs were read by a Harshaw 3500 TLD reader. Results: Total measured dose (in Gy of various parts of spinal cord adjacent to second cervical to fourth thoracic vertebra varied widely and were as follows respectively: 15.24±1.31, 50.31±1.06, 49.15±2.77, 47.48±1.42, 54.56±2.6, 48.92±0.6, 45.1±0.45. In other words, the range of doses received by different segments of the spinal cord could be as wide as 15.24 to 54.56 Gy. Conclusion: Although the spinal cord was excluded at the end of the first phase, a significant change in the absorbed dose at the end of the first and second phases was not observed. In phase three, the anterior neck field was replaced by a lateral field and the spinal cord absorbed dose was reduced considerably. According to our results, absorbed doses of the spinal cord segments corresponding to the region confined between the third cervical to third thoracic vertebra were more than the 47 Gy

  14. Preliminary assessment of radiological doses in alternative waste management systems without an MRS facility

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, K.J.; Pelto, P.J.; Daling, P.M.; Lavender, J.C.; Fecht, B.A.

    1986-06-01

    This report presents generic analyses of radiological dose impacts of nine hypothetical changes in the operation of a waste management system without a monitored retrievable storage (MRS) facility. The waste management activities examined in this study include those for handling commercial spent fuel at nuclear power reactors and at the surface facilities of a deep geologic repository, and the transportation of spent fuel by rail and truck between the reactors and the repository. In the reference study system, the radiological doses to the public and to the occupational workers are low, about 170 person-rem/1000 metric ton of uranium (MTU) handled with 70% of the fuel transported by rail and 30% by truck. The radiological doses to the public are almost entirely from transportation, whereas the doses to the occupational workers are highest at the reactors and the repository. Operating alternatives examined included using larger transportation casks, marshaling rail cars into multicar dedicated trains, consolidating spent fuel at the reactors, and wet or dry transfer options of spent fuel from dry storage casks. The largest contribution to radiological doses per unit of spent fuel for both the public and occupational workers would result from use of truck transportation casks, which are smaller than rail casks. Thus, reducing the number of shipments by increasing cask sizes and capacities (which also would reduce the number of casks to be handled at the terminals) would reduce the radiological doses in all cases. Consolidating spent fuel at the reactors would reduce the radiological doses to the public but would increase the doses to the occupational workers at the reactors.

  15. Radiation Dose Assessments for Shore-Based Individuals in Operation Tomodachi

    Science.gov (United States)

    2012-09-30

    Misawa AB Kyoto Kyoto Iwate Morioka City of Ofunato* Osaka Osaka Miyagi Sendai Camp Sendai* Hyogo Kobe Akita Akita Nara Nara Yamagata Yamagata... economy one day per week for the first month (a total of 4 days), the highest doses would have been calculated for a 1-year old child yielding values...Radiation dose estimates to people who were living solely on the local economy near U.S. military installations should be comparable to the values in

  16. Dynamic dose assessment by Large Eddy Simulation of the near-range atmospheric dispersion.

    Science.gov (United States)

    Vervecken, Lieven; Camps, Johan; Meyers, Johan

    2015-03-01

    In order to improve the simulation of the near-range atmospheric dispersion of radionuclides, computational fluid dynamics is becoming increasingly popular. In the current study, Large-Eddy Simulation is used to examine the time-evolution of the turbulent dispersion of radioactive gases in the atmospheric boundary layer, and it is coupled to a gamma dose rate model that is based on the point-kernel method with buildup factors. In this way, the variability of radiological dose rate from cloud shine due to instantaneous turbulent mixing processes can be evaluated. The steady release in an open field of (41)Ar and (133)Xe for 4 different release heights is studied, thus covering radionuclides that decay with a high-energy gamma and a low-energy gamma, respectively. Based on these simulations, the variability of dose rates at ground level for different averaging times in the dose measurements is analyzed. It is observed that turbulent variability in the wind field can lead to dose estimates that are underestimated by up to a factor of four when conventional long-term measurements are used to estimate the dose from short-term exposures.

  17. Assessment of patient dose and radiogenic risks during endoscopic retrograde cholangiopancreatography

    Energy Technology Data Exchange (ETDEWEB)

    Sulieman, A.; Elzaki, M. [Sudan University of Science and Technology, College of Medical Radiologic Science, P. O. Box 1908, Khartoum 11111 (Sudan); Alkhorayef, M.; Babikir, E. [King Saud University, College of Applied Sciences, Radiological Sciences Department, P. O. Box 10219, Riyadh 11433 (Saudi Arabia); Abuzaid, M. [University of Sharjah, College of Health Sciences, Medical Diagnostic Imaging Department, Sharjah (United Arab Emirates); Dalton, A.; Bradley, D., E-mail: Abdelmoneim_a@yahoo.com [University of Surrey, Centre for Nuclear and Radiation Physics, Department of Physics, GU2-7XH, Guildford, Surrey (United Kingdom)

    2015-10-15

    Endoscopic retrograde cholangiopancreatography (ERCP) is an invasive technique that has been used for over 30 years in the diagnosis and management of pancreaticobiliary disorders. The objectives of this study were to evaluate the patient entrance surface air kerma doses (ESAK) and estimate the organ and effective doses during ERCP in three hospitals in Khartoum. A total of 55 patients were examined in three hospitals in Khartoum state, Sudan. Calibrated thermoluminescence dosimeters (TLD)-Gr-200-A)) were used to measure patients ESAK. The overall mean of ESAK for all ERCP procedures was 42.4 mGy. The mean patient ESAK in Fedail, Soba and Ibn sena centers were 26.7 mGy, 26.0 mGy, 72.4 mGy, respectively. The effective doses in three centers were 1.6, 1.56 and 2.67 mSv in that order and the overall mean effective dose was 2.01 mSv. Patient radiation doses vary widely among the different hospitals. Patient ESAK is low compared to previous studies in the light of the current practice. Patient dose was decreased significantly in the last two decades. (Author)

  18. Dual-resolution dose assessments for proton beamlet using MCNPX 2.6.0

    Science.gov (United States)

    Chao, T. C.; Wei, S. C.; Wu, S. W.; Tung, C. J.; Tu, S. J.; Cheng, H. W.; Lee, C. C.

    2015-11-01

    The purpose of this study is to access proton dose distribution in dual resolution phantoms using MCNPX 2.6.0. The dual resolution phantom uses higher resolution in Bragg peak, area near large dose gradient, or heterogeneous interface and lower resolution in the rest. MCNPX 2.6.0 was installed in Ubuntu 10.04 with MPI for parallel computing. FMesh1 tallies were utilized to record the energy deposition which is a special designed tally for voxel phantoms that converts dose deposition from fluence. 60 and 120 MeV narrow proton beam were incident into Coarse, Dual and Fine resolution phantoms with pure water, water-bone-water and water-air-water setups. The doses in coarse resolution phantoms are underestimated owing to partial volume effect. The dose distributions in dual or high resolution phantoms agreed well with each other and dual resolution phantoms were at least 10 times more efficient than fine resolution one. Because the secondary particle range is much longer in air than in water, the dose of low density region may be under-estimated if the resolution or calculation grid is not small enough.

  19. ASSESSMENT OF UNCERTAINTY IN THE RADIATION DOSES FOR THE TECHA RIVER DOSIMETRY SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Napier, Bruce A.; Degteva, M. O.; Anspaugh, L. R.; Shagina, N. B.

    2009-10-23

    In order to provide more accurate and precise estimates of individual dose (and thus more precise estimates of radiation risk) for the members of the ETRC, a new dosimetric calculation system, the Techa River Dosimetry System-2009 (TRDS-2009) has been prepared. The deterministic version of the improved dosimetry system TRDS-2009D was basically completed in April 2009. Recent developments in evaluation of dose-response models in light of uncertain dose have highlighted the importance of different types of uncertainties in the development of individual dose estimates. These include uncertain parameters that may be either shared or unshared within the dosimetric cohort, and also the nature of the type of uncertainty as aleatory or epistemic and either classical or Berkson. This report identifies the nature of the various input parameters and calculational methods incorporated in the Techa River Dosimetry System (based on the TRDS-2009D implementation), with the intention of preparing a stochastic version to estimate the uncertainties in the dose estimates. This report reviews the equations, databases, and input parameters, and then identifies the author’s interpretations of their general nature. It presents the approach selected so that the stochastic, Monte-Carlo, implementation of the dosimetry System - TRDS-2009MC - will provide useful information regarding the uncertainties of the doses.

  20. Summary of the JCO criticality accident in Tokai-mura and a dose assessment.

    Science.gov (United States)

    Tanaka, S I

    2001-09-01

    A criticality accident occurred on September 30, 1999, in a conversion test facility at the JCO Tokai site. The accident was triggered by pouring an 18.8% enriched uranyl nitrate solution into a precipitation vessel beyond the critical mass. The accident continued for about 19 hours before the criticality could be stopped. during which time neutrons and gamma-rays were emitted continuously due to fission reactions. The total number of fission reactions was 2.5 x 10(18), which was estimated by an activity analysis of the fission products in the solution of the precipitation vessel. The accident gave serious radiation dose to 3 employees and fatal dose to 2 of them. Neutrons and gamma-rays emitted by the accident caused meaningful doses to the residents of the surrounding area of JCO. The dominant dose to the residents and JCO employees was brought by neutrons and gamma-rays from the precipitation vessel, while the contribution of radioactive plume was negligible. The individual dose was estimated for 234 resident, 169 JCO employees and 260 emergency personnel. The maximum doses were 21 mSv for the residents, 48mSv for the JCO employees, and 9.4mSv for the emergency personnel, respectively. No deterministic effect, however, has been observed, except for the 3 workers.

  1. Health risk of low-dose pesticides mixtures: a review of the 1985-1998 literature on combination toxicology and health risk assessment.

    Science.gov (United States)

    Carpy, S A; Kobel, W; Doe, J

    2000-01-01

    A literature review covering the last 14 yr has been performed in the field of combination toxicology and human risk assessment from exposure to chemical mixtures, with special emphasis on mixtures of pesticides at low doses, that is, at levels likely to occur in human diet and environment. Despite a large body of knowledge in the field of risk assessment methodologies for exposure to chemical and pesticide mixtures, there is no single methodological approach in "combination toxicology" and health risk assessment of chemical mixtures, and therefore professional judgment is still required. Generally, the dose or response additivity approach that may be applied to evaluate potential risk for chemical mixtures in human toxicology overestimates the risk of a combination of chemicals. The recent endocrine disrupter issue demonstrated the difficulty of reproducibility of data when testing environmental toxicants at very low levels, and the need for more basic work in this field. The use of integrated methodological approaches may provide more reliable predictive data in the risk assessment of chemical mixtures in future. Yet data have demonstrated that exposure to a combination of compounds does not cause effects stronger than the ones of their most active component, provided components are present at low concentration levels, like acceptable daily intake (ADI) or reference dose (RfD) levels, well below their respective no-observed-adverse-effect levels (NOAELs). Although it has been demonstrated that a combination of compounds with the same target organ and the same or very similar mechanisms of action may cause additive or synergistic effects, the chance of such effects will most likely diminish with decreasing exposure levels to such combinations. Synergism and antagonism may both occur at the same time at different organs or targets in the same organism. However, and despite some exceptions, it has been demonstrated that interaction between components is not a common

  2. Accurate dose assessment system for an exposed person utilising radiation transport calculation codes in emergency response to a radiological accident.

    Science.gov (United States)

    Takahashi, F; Shigemori, Y; Seki, A

    2009-01-01

    A system has been developed to assess radiation dose distribution inside the body of exposed persons in a radiological accident by utilising radiation transport calculation codes-MCNP and MCNPX. The system consists mainly of two parts, pre-processor and post-processor of the radiation transport calculation. Programs for the pre-processor are used to set up a 'problem-dependent' input file, which defines the accident condition and dosimetric quantities to be estimated. The program developed for the post-processor part can effectively indicate dose information based upon the output file of the code. All of the programs in the dosimetry system can be executed with a generally used personal computer and accurately give the dose profile to an exposed person in a radiological accident without complicated procedures. An experiment using a physical phantom was carried out to verify the availability of the dosimetry system with the developed programs in a gamma ray irradiation field.

  3. Assessment of infant dose through milk in a lactating woman taking amisulpride and desvenlafaxine for treatment-resistant depression.

    Science.gov (United States)

    Ilett, Kenneth F; Watt, Felice; Hackett, L Peter; Kohan, Rolland; Teoh, Stephanie

    2010-12-01

    This study presents the case of a 35-year-old breastfeeding mother who delivered her fourth child 5 months previously and was prescribed 100 mg amisulpride twice daily and 250 mg desvenlafaxine in the morning for treatment-resistant depression. Arriving at this regimen took approximately 2 months postbirth. Because she was keen to continue breastfeeding her infant, and published data on the use of amisulpride and desvenlafaxine were very limited, the clinical team sought assistance from the therapeutic drug monitoring laboratory to quantify infant dose-exposure to guide consideration of continuing breastfeeding. A sampling schedule for milk and plasma from mother and plasma from her infant was agreed and drug concentrations were measured by high-performance liquid chromatography. Absolute (theoretic) infant dose (μg/kg/d) was calculated as the product of the average concentration in milk and an assumed milk intake of 0.15 L/kg/day (294 mg/kg/day for desvenlafaxine and 183 mg/kg/day for amisulpride), and relative infant dose was estimated as absolute infant dose expressed as a percentage of the maternal dose in μg/kg/day (7.8% for desvenlafaxine and 6.1% for amisulpride). Consistent with the infant being partially breastfed, the ratio of drug in the infant's plasma to that in mother's plasma was lower at 1.7% for desvenlafaxine and 3.9% for amisulpride. A pediatric assessment of the infant found achievement of expected developmental progress for age and no detectable drug-related adverse effects. Assessing the safety of breastfeeding was difficult because it involved simultaneous use of two drugs for which there was limited previous experience. However, after discussion of the infant dose-exposure data and lack of adverse effects, the mother elected to continue partial breastfeeding for the next few months. The clinical team plans a reassessment of the infant's progress in 3 months.

  4. Assessing patient dose in interventional fluoroscopy using patient-dependent hybrid phantoms

    Science.gov (United States)

    Johnson, Perry Barnett

    Interventional fluoroscopy uses ionizing radiation to guide small instruments through blood vessels or other body pathways to sites of clinical interest. The technique represents a tremendous advantage over invasive surgical procedures, as it requires only a small incision, thus reducing the risk of infection and providing for shorter recovery times. The growing use and increasing complexity of interventional procedures, however, has resulted in public health concerns regarding radiation exposures, particularly with respect to localized skin dose. Tracking and documenting patient-specific skin and internal organ dose has been specifically identified for interventional fluoroscopy where extended irradiation times, multiple projections, and repeat procedures can lead to some of the largest doses encountered in radiology. Furthermore, inprocedure knowledge of localized skin doses can be of significant clinical importance to managing patient risk and in training radiology residents. In this dissertation, a framework is presented for monitoring the radiation dose delivered to patients undergoing interventional procedures. The framework is built around two key points, developing better anthropomorphic models, and designing clinically relevant software systems for dose estimation. To begin, a library of 50 hybrid patient-dependent computational phantoms was developed based on the UF hybrid male and female reference phantoms. These phantoms represent a different type of anthropomorphic model whereby anthropometric parameters from an individual patient are used during phantom selection. The patient-dependent library was first validated and then used in two patient-phantom matching studies focused on cumulative organ and local skin dose. In terms of organ dose, patient-phantom matching was shown most beneficial for estimating the dose to large patients where error associated with soft tissue attenuation differences could be minimized. For small patients, inherent difference

  5. Assessment of the radiological impact of gamma and radon dose rates at former U mining sites in Tajikistan.

    Science.gov (United States)

    Lespukh, E; Stegnar, P; Yunusov, M; Tilloboev, H; Zyazev, G; Kayukov, P; Hosseini, A; Strømman, G; Salbu, B

    2013-12-01

    An assessment of the radiological situation due to exposure to gamma radiation, radon ((222)Rn) and thoron ((220)Rn) was carried out at former uranium (U) mining and processing sites in Taboshar and at Digmai in Tajikistan. Gamma dose rate measurements were made using various field instruments. (222)Rn/(220)Rn measurements were carried out with field instruments for instantaneous measurements and then discriminative (222)Rn/(220)Rn solid state nuclear track detectors (SSNTD) were used for longer representative measurements. The detectors were exposed for an extended period of time in different outdoor and indoor public and residential environments at the selected U legacy sites. The results showed that gamma, (222)Rn and (220)Rn doses were in general low, which consequently implies a low to relatively low radiological risk. The radiation doses deriving from external radiation (gamma dose rate), indoor (222)Rn and (220)Rn with their short-lived progenies did not exceed national or international standards. At none of the sites investigated did the average individual annual effective doses exceed 10 mSv, the recommended threshold value for the general public. A radiation hazard could be associated with exceptional situations, such as elevated exposures to ionizing radiation at the Digmai tailings site and/or in industrial facilities, where gamma and (222)Rn/(220)Rn dose rates could reach values of several 10 mSv/a. Current doses of ionizing radiation do not represent a hazard to the health of the resident public, with the exception of some specific situations. These issues should be adequately addressed to further reduce needless exposure of the resident public to ionizing radiation.

  6. Assessment of target volume doses in radiotherapy based on the standard and measured calibration curves

    Directory of Open Access Journals (Sweden)

    Gholamreza Fallah Mohammadi

    2015-01-01

    Full Text Available Context: In radiation treatments, estimation of the dose distribution in the target volume is one of the main components of the treatment planning procedure. To estimate the dose distribution, the information of electron densities is necessary. The standard curves determined by computed tomography (CT scanner that may be different from that of other oncology centers. In this study, the changes of dose calculation due to the different calibration curves (HU-ρel were investigated. Materials and Methods: Dose values were calculated based on the standard calibration curve that was predefined for the treatment planning system (TPS. The calibration curve was also extracted from the CT images of the phantom, and dose values were calculated based on this curve. The percentage errors of the calculated values were determined. Statistical Analysis Used: The statistical analyses of the mean differences were performed using the Wilcoxon rank-sum test for both of the calibration curves. Results and Discussion: The results show no significant difference for both of the measured and standard calibration curves (HU-ρel in 6, 15, and 18 MeV energies. In Wilcoxon ranked sum nonparametric test for independent samples with P < 0.05, the equality of monitor units for both of the curves to transfer 200 cGy doses to reference points was resulted. The percentage errors of the calculated values were lower than 2% and 1.5% in 6 and 15 MeV, respectively. Conclusion: From the results, it could be concluded that the standard calibration curve could be used in TPS dose calculation accurately.

  7. Assessment of ocular beta radiation dose distribution due to 106Ru/106Rh brachytherapy applicators using MCNPX Monte Carlo code

    Directory of Open Access Journals (Sweden)

    Nilseia Aparecida Barbosa

    2014-08-01

    heterogeneous eye model, indicating that the homogeneous water eye model is a reasonable one. The determined isodose curves give a good visualization of dose distributions inside the eye structures, pointing out their most exposed volume....................................................Cite this article as:Barbosa NA, da Rosa LAR, de Menezes AF, Reis JP, Facure A, Braz D. Assessment of ocular beta radiation dose distribution due to 106Ru/106Rh brachytherapy applicators using MCNPX Monte Carlo code. Int J Cancer Ther Oncol 2014; 2(3:02038. DOI: 10.14319/ijcto.0203.8

  8. Generation of dose-response relationships to assess the effects of acidity in precipitation on growth and productivity of vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.S.

    1981-01-01

    Experiments were performed with several plant species in natural environments as well in a greenhouse and/or tissue culture facilities to establish dose-response functions of plant responses to simulated acidic rain in order to determine environmental risk assessments to ambient levels of acidic rain. Response functions of foliar injury, biomass of leaves and seed of soybean and pinto beans, root yields of radishes and garden beets, and reproduction of bracken fern are considered. The dose-response function of soybean seed yields with the hydrogen ion concentration of simulated acidic rainfalls was expressed by the equation y = 21.06-1.01 log x where y = seed yield in grams per plant and x = the hydrogen concentration if ..mu..eq l/sup -1/. The correlation coefficient of this relationship was -0.90. A similar dose-response function was generated for percent fertilization of ferns in a forest understory. When percent fertilization is plotted on logarithmic scale with hydrogen ion concentration of the simulated rain solution, the Y intercept is 51.18, slope -0.041 with a correlation coefficient of -0.98. Other dose-response functions were generated that assist in a general knowledge as to which plant species and which physiological processes are most impacted by acidic precipitation. Some responses did not produce convenient dose-response relationships. In such cases the responses may be altered by other environmental factors or there may be no differences among treatment means.

  9. Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead

    Science.gov (United States)

    Goodson, William H.; Lowe, Leroy; Carpenter, David O.; Gilbertson, Michael; Manaf Ali, Abdul; Lopez de Cerain Salsamendi, Adela; Lasfar, Ahmed; Carnero, Amancio; Azqueta, Amaya; Amedei, Amedeo; Charles, Amelia K.; Collins, Andrew R.; Ward, Andrew; Salzberg, Anna C.; Colacci, Anna Maria; Olsen, Ann-Karin; Berg, Arthur; Barclay, Barry J.; Zhou, Binhua P.; Blanco-Aparicio, Carmen; Baglole, Carolyn J.; Dong, Chenfang; Mondello, Chiara; Hsu, Chia-Wen; Naus, Christian C.; Yedjou, Clement; Curran, Colleen S.; Laird, Dale W.; Koch, Daniel C.; Carlin, Danielle J.; Felsher, Dean W.; Roy, Debasish; Brown, Dustin G.; Ratovitski, Edward; Ryan, Elizabeth P.; Corsini, Emanuela; Rojas, Emilio; Moon, Eun-Yi; Laconi, Ezio; Marongiu, Fabio; Al-Mulla, Fahd; Chiaradonna, Ferdinando; Darroudi, Firouz; Martin, Francis L.; Van Schooten, Frederik J.; Goldberg, Gary S.; Wagemaker, Gerard; Nangami, Gladys N.; Calaf, Gloria M.; Williams, Graeme P.; Wolf, Gregory T.; Koppen, Gudrun; Brunborg, Gunnar; Lyerly, H. Kim; Krishnan, Harini; Ab Hamid, Hasiah; Yasaei, Hemad; Sone, Hideko; Kondoh, Hiroshi; Salem, Hosni K.; Hsu, Hsue-Yin; Park, Hyun Ho; Koturbash, Igor; Miousse, Isabelle R.; Scovassi, A.Ivana; Klaunig, James E.; Vondráček, Jan; Raju, Jayadev; Roman, Jesse; Wise, John Pierce; Whitfield, Jonathan R.; Woodrick, Jordan; Christopher, Joseph A.; Ochieng, Josiah; Martinez-Leal, Juan Fernando; Weisz, Judith; Kravchenko, Julia; Sun, Jun; Prudhomme, Kalan R.; Narayanan, Kannan Badri; Cohen-Solal, Karine A.; Moorwood, Kim; Gonzalez, Laetitia; Soucek, Laura; Jian, Le; D’Abronzo, Leandro S.; Lin, Liang-Tzung; Li, Lin; Gulliver, Linda; McCawley, Lisa J.; Memeo, Lorenzo; Vermeulen, Louis; Leyns, Luc; Zhang, Luoping; Valverde, Mahara; Khatami, Mahin; Romano, Maria Fiammetta; Chapellier, Marion; Williams, Marc A.; Wade, Mark; Manjili, Masoud H.; Lleonart, Matilde E.; Xia, Menghang; Gonzalez Guzman, Michael J.; Karamouzis, Michalis V.; Kirsch-Volders, Micheline; Vaccari, Monica; Kuemmerle, Nancy B.; Singh, Neetu; Cruickshanks, Nichola; Kleinstreuer, Nicole; van Larebeke, Nik; Ahmed, Nuzhat; Ogunkua, Olugbemiga; Krishnakumar, P.K.; Vadgama, Pankaj; Marignani, Paola A.; Ghosh, Paramita M.; Ostrosky-Wegman, Patricia; Thompson, Patricia A.; Dent, Paul; Heneberg, Petr; Darbre, Philippa; Leung, Po Sing; Nangia-Makker, Pratima; Cheng, Qiang (Shawn); Robey, R.Brooks; Al-Temaimi, Rabeah; Roy, Rabindra; Andrade-Vieira, Rafaela; Sinha, Ranjeet K.; Mehta, Rekha; Vento, Renza; Di Fiore, Riccardo; Ponce-Cusi, Richard; Dornetshuber-Fleiss, Rita; Nahta, Rita; Castellino, Robert C.; Palorini, Roberta; Hamid, Roslida A.; Langie, Sabine A.S.; Eltom, Sakina E.; Brooks, Samira A.; Ryeom, Sandra; Wise, Sandra S.; Bay, Sarah N.; Harris, Shelley A.; Papagerakis, Silvana; Romano, Simona; Pavanello, Sofia; Eriksson, Staffan; Forte, Stefano; Casey, Stephanie C.; Luanpitpong, Sudjit; Lee, Tae-Jin; Otsuki, Takemi; Chen, Tao; Massfelder, Thierry; Sanderson, Thomas; Guarnieri, Tiziana; Hultman, Tove; Dormoy, Valérian; Odero-Marah, Valerie; Sabbisetti, Venkata; Maguer-Satta, Veronique; Rathmell, W.Kimryn; Engström, Wilhelm; Decker, William K.; Bisson, William H.; Rojanasakul, Yon; Luqmani, Yunus; Chen, Zhenbang; Hu, Zhiwei

    2015-01-01

    Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety ‘Mode of Action’ framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology. PMID:26106142

  10. Flattening filter free beams in SBRT and IMRT. Dosimetric assessment of peripheral doses

    Energy Technology Data Exchange (ETDEWEB)

    Kragl, Gabriele; Baier, Franziska; Albrich, David; Kroupa, Bernhard; Georg, Dietmar [Medical Univ. of Vienna/AKH Vienna (Austria). Dept. of Radiotherapy; Lutz, Steffen; Wiezorek, Tilo [University Hospital Jena (Germany). Dept. of Radiotherapy; Dalaryd, Maarten; Knoeoes, Tommy [Lund Univ. (Sweden). Radiation Physics; Skaane Univ. Hospital (Sweden). Radiation Physics

    2011-07-01

    Purpose: Recently, there has been a growing interest in operating medical linear accelerators without a flattening filter. Due to reduced scatter, leaf transmission and radiation head leakage a reduction of out-of-field dose is expected for flattening filter free beams. The aim of the present study was to determine the impact of unflattened beams on peripheral dose for advanced treatment techniques with a large number of MUs. Material and methods: An Elekta Precise linac was modified to provide 6 and 10 MV photon beams without a flattening filter. Basic beam data were collected and implemented into the TPS Oncentra Masterplan (Nucletron). Leakage radiation, which predominantly contributes to peripheral dose at larger distances from the field edge, was measured using a Farmer type ionisation chamber. SBRT (lung) and IMRT (prostate, head and neck) treatment plans were generated for 6 and 10 MV for both flattened and unflattened beams. All treatment plans were delivered to the relevant anatomic region of an anthropomorphic phantom which was extended by a solid water slab phantom. Dosimetric measurements were performed with TLD-700 rods, radiochromic films and a Farmer type ionisation chamber. The detectors were placed within the slab phantom and positioned along the isocentric longitudinal axis. Results: Using unflattened beams results in a reduction of treatment head leakage by 52% for 6 and 65% for 10 MV. Thus, peripheral doses were in general smaller for treatment plans calculated with unflattened beams. At about 20 cm distance from the field edge the dose was on average reduced by 23 and 31% for the 6 and 10 MV SBRT plans. For the IMRT plans (10 MV) the average reduction was 16% for the prostate and 18% for the head and neck case, respectively. For all examined cases, the relative deviation between peripheral doses of flattened and unflattened beams was found to increase with increasing distance from the field. Conclusions: Removing the flattening filter lead to

  11. Assessing pharmacokinetics of different doses of fosfomycin in laboratory rats enables adequate exposure for pharmacodynamic models.

    Science.gov (United States)

    Poeppl, Wolfgang; Lingscheid, Tilman; Bernitzky, Dominik; Donath, Oliver; Reznicek, Gottfried; Zeitlinger, Markus; Burgmann, Heinz

    2014-01-01

    Fosfomycin has been the subject of numerous pharmacodynamic in vivo models in recent years. The present study set out to determine fosfomycin pharmacokinetics in laboratory rats to enable adequate dosing regimens in future rodent models. Fosfomycin was given intraperitoneally as single doses of 75, 200 and 500 mg/kg bodyweight to 4 Sprague-Dawley rats per dose group. Blood samples were collected over 8 h and fosfomycin concentrations were determined by HPLC-mass spectrometry. Fosfomycin showed a dose-proportional pharmacokinetic profile indicated by a correlation of 0.99 for maximum concentration and area under the concentration-time curve (AUC). The mean AUC0-8 after intraperitoneal administration of 75, 200 or 500 mg/kg bodyweight fosfomycin were 109.4, 387.0 and 829.1 µg·h/ml, respectively. In conclusion, a dosing regimen of 200-500 mg/kg 3 times daily is appropriate to obtain serum concentrations in laboratory rats, closely mimicking human serum concentrations over time.

  12. Assessment of dose in thyroid and salivary glands in dental radiology using thermoluminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Mantuano, Natalia de O.; Silva, Ademir X. da [Instituto Alberto Luiz Coimbra de Pos-Graduacao e Pesquisa em Engenharia (PEN/COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear; Canevaro, Luca V.; Mauricio, Claudia Lucia P. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ) Rio de Janeiro, RJ (Brazil); Correa, Samanda C.A., E-mail: scorrea@cnen.gov.b [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Radiobiological and epidemiological studies have provided evidence of risk of salivary and thyroid glands tumors incidence associated with oral radiology. Based on these studies, the tissue weighting factors were reviewed by the International Commission on Radiological Protection (ICRP) in 2007. The main objective of the present work is to estimate the absorbed dose on thyroid and salivary glands (parotid, submandibular and sublingual), during a complete periapical examination. The complete periapical examination was simulated using a Spectro 70X Seletronic X-ray dental equipment on an Alderson Rando phantom with Harshaw LiF:Mg,Ti thermoluminescent dosemeters (TLD100). A PTW DIADOS dosimetric system was used for calibration. The TLD100 were inserted into the phantom slices corresponding to the organs of interest. During a complete periapical examination, the highest evaluated mean absorbed dose was 4.9 mGy in the right submandibular gland and the lowest one of 1.5 mGy in the left thyroid lobe. Entrance surface doses ranged from 2.1 to 2.6 mGy, measured, respectively, for the techniques of upper left molar and lower right molar. When compared with the diagnostic reference levels (DRL), the entrance surface doses values were lower than the DRLs recommended in Brazilian current legislation. However, the dosimetric results show the need of optimization for complete periapical examination to minimize patient exposure. Measurements were performed without the use of thyroid protectors. The use of this device is certainly an easy and simple method of dose reduction. (author)

  13. Safety assessments of subcutaneous doses of aragonite calcium carbonate nanocrystals in rats

    Science.gov (United States)

    Jaji, Alhaji Zubair; Zakaria, Zuki Abu Bakar; Mahmud, Rozi; Loqman, Mohamad Yusof; Hezmee, Mohamad Noor Mohamad; Abba, Yusuf; Isa, Tijani; Mahmood, Saffanah Khuder

    2017-05-01

    Calcium carbonate nanoparticles have shown promising potentials in the delivery of drugs and metabolites. There is however, a paucity of information on the safety of their intentional or accidental over exposures to biological systems and general health safety. To this end, this study aims at documenting information on the safety of subcutaneous doses of biogenic nanocrystals of aragonite polymorph of calcium carbonate derived from cockle shells (ANC) in Sprague-Dawley (SD) rats. ANC was synthesized using the top-down method, characterized using the transmission electron microscopy and field emission scanning electron microscope and its acute and repeated dose 28-day trial toxicities were evaluated in SD rats. The results showed that the homogenous 30 ± 5 nm-sized spherical pure aragonite nanocrystals were not associated with mortality in the rats. Severe clinical signs and gross and histopathological lesions, indicating organ toxicities, were recorded in the acute toxicity (29,500 mg/m2) group and the high dose (5900 mg/m2) group of the repeated dose 28-day trial. However, the medium- (590 mg/m2 body weight) and low (59 mg/m2)-dose groups showed moderate to mild lesions. The relatively mild lesions observed in the low toxicity dosage group marked the safety margin of ANC in SD rats. It was concluded from this study that the toxicity of CaCO3 was dependent on the particulate size (30 ± 5 nm) and concentration and the route of administration used.

  14. Assessing renal function in children with hydronephrosis - additional feature of MR urography.

    Science.gov (United States)

    Hadjidekov, George; Hadjidekova, Savina; Tonchev, Zahari; Bakalova, Rumiana; Aoki, Ichio

    2011-12-01

    Magnetic resonance urography (MRU) is one of the most attractive imaging modalities in paediatric urology, providing largest diagnostic information in a single protocol. Therefore, the aim of our study was to assess the diagnostic value of MRU in children with urogenital anomalies (especially anomalies of the renal pelvis and ureter) and the renal function using different post-processing functional software. Ninety six children (7 days - 18 years old) were examined. In 54 patients of them, a static T(2) MRU was completed by excretory T(1) MRU after gadolinium administration and functional analysis has been performed using two functional analysis softwares "CHOP-fMRU" and "ImageJ" software. MRU showed suspicious renal and the whole urinary tract anomalies with excellent image quality in all children. In ureteropelvic obstruction, MRU was confirmatory to the other imaging techniques, but it was superior modality concerning the evaluation of end-ureteral anomalies. There was an excellent correlation between the MRU data and diagnosis, determined by surgery. The renal transit times, renal volumes and volumetric differential renal function were assessed separately by "CHOP-fMRU" and "ImageJ" with excellent agreement with 99(m)Tc-DTPA and among them. MRU overcomes a lot of limitations of conventional imaging modalities and has a potential to become a leading modality in paediatric uroradiology. Synthesis of both anatomical and functional criteria in MR urography enables to select the best candidates for surgical treatment. Even small kidney dysfunction can be detected by functional analysis software.

  15. [Comprehensive Assessment of Psychiatric Residents: An Addition to the Program Admission Process].

    Science.gov (United States)

    Luis, E Jaramillo G; Elena, Martín C

    2012-01-01

    The training of medical specialists is a long and complex process. Its purpose is to guarantee the society that they are the right professionals to meet the health needs of the population. The first step to ensure this objective is the admission process. In psychiatry this process, monitoring resident students and the criteria for each one are different in each country. Admission in Colombia is a heterogeneous process, not standardized, which varies greatly from one university to another, even between private and public universities. At the National University of Colombia, the admissions process is handled by the Admissions Office and includes: a written test for which you must obtain a minimum score, a resume rating and an interview. The Teaching Committee and the Department of Psychiatry considered the admission procedure in general to be good, but in need of refinement. Due to the experience of some teachers and given the current rules, a "comprehensive assessment" for master and doctoral students was required and in 1996 it was decided that this method of assessment for admission to a specialization in Psychiatry would serve to complement the admission process. The article describes the experience of the process and its outcomes, strengths and weaknesses. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  16. Assessment of production performance in 2 breeds of broilers fed prebiotics as feed additives.

    Science.gov (United States)

    Hanning, I; Clement, A; Owens, C; Park, S H; Pendleton, S; Scott, E E; Almeida, G; Gonzalez Gil, F; Ricke, S C

    2012-12-01

    Pasture-flock-raised poultry are becoming an increasingly popular product, but only limited options are currently available for maintaining gut health. For these producers, prebiotics are an attractive option because they are generally recognized as safe (GRAS) and can be mixed into the feed and thus do not require adjustments to production protocols. However, if prebiotic treatments reduce production performance, they would not be useful to producers. Thus, the objective of this study was to measure performance of pasture-raised broilers fed 1 of 3 prebiotic treatments. For these trials, 2 breeds of birds were used: Naked Neck slow-growing breeds and Cornish White Rock cross fast-growing breeds. The experimental design was replicated for each breed. A total of 340 birds were split into 4 groups, each group fed one feed additive: 1) galactoligosaccharides (2% wt/wt), 2) fructooligosaccharides (1% wt/wt), 3) plum fibers (1% wt/wt), or 4) no additives. During the 8-wk rearing period, 10 birds from each group were collected and euthanized to take small intestine samples. Histological preparations were made from the small intestine tissue, and 4 measurements of villi height and crypt depth from each cross section were taken. Throughout the study, mortality was monitored and BW measurements were taken at 2-wk intervals. For the Cornish White Rock cross, the group receiving the feed supplemented with fructooligosaccharides had higher (P prebiotics utilized in this study could be used without risk of decreasing production performance, but only for Naked Neck breeds.

  17. Radiological-dose assessments of atolls in the northern Marshall Islands

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W.L.

    1983-04-01

    The Marshall Islands in the Equatorial Pacific, specifically Enewetak and Bikini Atolls, were the site of US nuclear testing from 1946 through 1958. In 1978, the Northern Marshall Islands Radiological Survey was conducted to evaluate the radiological conditions of two islands and ten atolls downwind of the proving grounds. The survey included aerial external gamma measurements and collection of soil, terrestrial, and marine samples for radionuclide analysis to determine the radiological dose from all exposure pathways. The methods and models used to estimate doses to a population in an environment where natural processes have acted on the source-term radionuclides for nearly 30 y, data bases developed for the models, and results of the radiological dose analyses are described.

  18. Assessment of potential radiation dose rates to marine organisms around the Korean Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Myung [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Lee, Jun Ho [University of Science and Technology, Daejeon (Korea, Republic of)

    2016-05-15

    It is very difficult to set a regulatory guidance or criteria for the protection of non-human species from the ionizing radiation, because there are no generally or internationally accepted methods for demonstrating the compliance with such criteria. It is needed that Korea develop the primary dose rate standards for the protection of both aquatic and terrestrial biota in the near future. The potential dose rates due to both external and internal radiation exposures to marine organisms such as plaice/flounder, gray mullet, and brown seaweed collected within territorial seas around the Korean Peninsula were estimated. The total dose rates to plaice/flounder, gray mullet and brown seaweed due to {sup 40}K, a primordial radionuclide in marine environment, were found to be 0.2%, 0.08% and 0.3% of approximately the values of the Derived Consideration Reference Levels (DCRLs, i.e. 1-10 mGy d{sup -1}), respectively, as suggested by the International Commission on Radiological Protection (ICRP) publication 124. The total dose rates to marine fishes and brown seaweed due to anthropogenic radionuclides such as {sup 90}Sr, {sup 137}Cs and {sup 239+240}Pu were considered to be negligible compared to the total dose rate due to {sup 40}K. The external exposure to benthic fish due to all radionuclides was much higher than that of pelagic fish. From this study, it is recommended that the further study is required to develop a national regulatory guidance for the evaluation of doses to non-human species.

  19. A study to investigate fluoride contamination and fluoride exposure dose assessment in lateritic zones of West Bengal, India.

    Science.gov (United States)

    Samal, Alok C; Bhattacharya, Piyal; Mallick, Anusaya; Ali, Md Motakabber; Pyne, Jagadish; Santra, Subhas C

    2015-04-01

    To assess the status of severity of fluoride contamination in lateritic Bankura and Purulia districts of West Bengal, concentrations of fluoride in different water sources and agricultural field soils were investigated. The fluoride content (mg/l) was observed to differ with aquifer depths: 0.19-0.47 in dug wells, 0.01-0.17 in shallow tube wells, and 0.07-1.6 in deep tube wells. Fluoride within the World Health Organization (WHO) prescribed range (1.0-1.5 mg/l) was estimated only in ~17% of the total collected water samples while ~67% showed fluoride and thus may impede in the production and maintenance of healthy teeth and bones of the residents, especially children. Fluoride in water was found to be significantly correlated (r = 0.63) with pH. The exposure dose of fluoride (mg/kg/day) from drinking water in infants, children, and adults was estimated in the ranges 0.02-0.53, 0.01-0.24, and 0.01-0.14, respectively against the standard value of 0.05. A clear risk of dental fluorosis is apparent in infants and children of the study area. The fluoride in soil (55-399 mg/kg) was detected to be significantly correlated with the fluoride content in deep tube wells and soil pH (r = 0.56 and 0.71, respectively). The relationships of soil fluoride with total hardness and that with phosphate were not significant. There is a high possibility of bioaccumulation of fluoride from contaminated soil and water of the study area to cultivated crops. This will enhance the quantity of fluoride intake into human food chain in addition to drinking water pathway.

  20. Assessing the effects of adsorptive polymeric resin additions on fungal secondary metabolite chemical diversity

    Science.gov (United States)

    González-Menéndez, Víctor; Asensio, Francisco; Moreno, Catalina; de Pedro, Nuria; Monteiro, Maria Candida; de la Cruz, Mercedes; Vicente, Francisca; Bills, Gerald F.; Reyes, Fernando; Genilloud, Olga; Tormo, José R.

    2014-01-01

    Adsorptive polymeric resins have been occasionally described to enhance the production of specific secondary metabolites (SMs) of interest. Methods that induce the expression of new chemical entities in fungal fermentations may lead to the discovery of new bioactive molecules and should be addressed as possible tools for the creation of new microbial chemical libraries for drug lead discovery. Herein, we apply both biological activity and chemical evaluations to assess the use of adsorptive resins as tools for the differential expression of SMs in fungal strain sets. Data automation approaches were applied to ultra high performance liquid chromatography analysis of extracts to evaluate the general influence in generating new chemical entities or in changing the production of specific SMs by fungi grown in the presence of resins and different base media. PMID:25379340

  1. Assessing renal function in children with hydronephrosis – additional feature of MR urography

    Science.gov (United States)

    Hadjidekov, George; Hadjidekova, Savina; Tonchev, Zahari; Bakalova, Rumiana; Aoki, Ichio

    2011-01-01

    Background Magnetic resonance urography (MRU) is one of the most attractive imaging modalities in paediatric urology, providing largest diagnostic information in a single protocol. Therefore, the aim of our study was to assess the diagnostic value of MRU in children with urogenital anomalies (especially anomalies of the renal pelvis and ureter) and the renal function using different post-processing functional software. Patients and methods Ninety six children (7 days – 18 years old) were examined. In 54 patients of them, a static T2 MRU was completed by excretory T1 MRU after gadolinium administration and functional analysis has been performed using two functional analysis softwares “CHOP-fMRU” and “ImageJ” software. Results MRU showed suspicious renal and the whole urinary tract anomalies with excellent image quality in all children. In ureteropelvic obstruction, MRU was confirmatory to the other imaging techniques, but it was superior modality concerning the evaluation of end-ureteral anomalies. There was an excellent correlation between the MRU data and diagnosis, determined by surgery. The renal transit times, renal volumes and volumetric differential renal function were assessed separately by “CHOP-fMRU” and “ImageJ” with excellent agreement with 99mTc-DTPA and among them. Conclusions MRU overcomes a lot of limitations of conventional imaging modalities and has a potential to become a leading modality in paediatric uroradiology. Synthesis of both anatomical and functional criteria in MR urography enables to select the best candidates for surgical treatment. Even small kidney dysfunction can be detected by functional analysis software. PMID:22933962

  2. Dose assessment from domestic building materials used in housing sector in Serbia.

    Science.gov (United States)

    Petrović, M; Vučić, D; Karamarković, J

    2014-11-01

    The results of mass activity measuring in many domestic building materials used in a housing sector are presented. Natural radionuclides (40)K, (226)Ra, (232)Th, (235)U and (238)U as well as artificial radionuclide (137)Cs were detected using a gamma spectrometry. Based on measured mass activity values, the absorbed dose rate from examined building materials was calculated following EC standards. According to the UNSCEAR procedure, the annual effective dose was also calculated. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Generalized additive models and Lucilia sericata growth: assessing confidence intervals and error rates in forensic entomology.

    Science.gov (United States)

    Tarone, Aaron M; Foran, David R

    2008-07-01

    Forensic entomologists use blow fly development to estimate a postmortem interval. Although accurate, fly age estimates can be imprecise for older developmental stages and no standard means of assigning confidence intervals exists. Presented here is a method for modeling growth of the forensically important blow fly Lucilia sericata, using generalized additive models (GAMs). Eighteen GAMs were created to predict the extent of juvenile fly development, encompassing developmental stage, length, weight, strain, and temperature data, collected from 2559 individuals. All measures were informative, explaining up to 92.6% of the deviance in the data, though strain and temperature exerted negligible influences. Predictions made with an independent data set allowed for a subsequent examination of error. Estimates using length and developmental stage were within 5% of true development percent during the feeding portion of the larval life cycle, while predictions for postfeeding third instars were less precise, but within expected error.

  4. Assessment of quality of platelets preserved in plasma and platelet additive solution: A Malaysian experience

    Directory of Open Access Journals (Sweden)

    Munirah Binti Mokhtar

    2016-01-01

    Full Text Available Background: A use of platelet additives solution (PAS improves storage conditions so as to give increased shelf life to platelets and to maintain hemostatic function. Objective: The present study was aimed to compare in vitro quality of platelet rich plasma (PRP-derived platelet concentrate (PC during extended period of storage in plasma and in additive solution (Composol PS and Fresenius. Study Design: Randomized 19 PCs each were used in the study for plasma and PAS as the storage medium. The measurement parameters, including pH, total white blood cell (WBC count, total platelet count, and platelet activation rate, were studied on day 1, day 5, and day 8 of the storage period. The sterility test was carried out on the eighth day of storage. Results: pH of PC suspended in PAS was significantly lower as compared to that in plasma (P < 0.001 for all the three days of sampling. The WBC count, both in plasma and in PAS, showed an acceptable values of being <0.2 Χ 10 9 /unit during the storage period. Platelet count in PAS was higher as compared to that in plasma, though it was not statistically significant. While both the groups showed increased platelet activation rate during the storage, the PCs suspended in PAS showed significantly higher platelet activation rate (p0.001. Results from sterility test showed no bacterial growth in the PCs in both the groups. Conclusion: Most parameters studied on platelet storage in suspending medium of native plasma and PAS remained well within the acceptable limits. However, the pH values and platelet activation rate significantly differed in PAS as compared with plasma.

  5. Enhanced Engraftment of a Very Low-Dose Cord Blood Unit in an Adult Haemopoietic Transplant by Addition of Six Mismatched Viable Cord Units

    Directory of Open Access Journals (Sweden)

    Stephen J. Proctor

    2010-01-01

    , supported by six mismatched cord blood units (one unit per 10 kg recipient weight. No adverse reaction occurred following the infusion of mismatched units and engraftment of the suboptimal-dose matched unit occurred rapidly, with no molecular evidence of engraftment of mismatched cords. Early molecular remission of ALL was demonstrated using a novel PCR for a mitochondrial DNA mutation in the leukaemic clone. The cell dose of the matched cord was well below that recommended to engraft a 70 kg recipient. We suggest that a factor or factors in the mismatched cords enhanced/supported engraftment of the matched cord.

  6. Assessing the risk of birth defects associated with exposure to fixed-dose combined antituberculous agents during pregnancy in rats.

    Science.gov (United States)

    Awodele, O; Patrick, E B; Oluwatoyin Agbaje, Esther; Oremosu, A A; Gbotolorun, S C

    2012-01-01

    Due to the risks of disease progression and transmission to the newborn, treatment of tuberculosis is often pursued during pregnancy and fixed-dose combined antituberculous agents have been found to be beneficial. Unfortunately, there is paucity of data on the safety of the fixed-dose combined antituberculous drugs during pregnancy. This study intends to assess the teratogenic effect of fixed-dose combined antituberculous drugs on the organogenesis stage of fetal development and also investigate the possible roles of vitamin C in modulating the teratogenic effects of these agents on the fetus using animal model. Pregnant rats were divided into 3 groups with 12 animals per group: group 1 received distilled water (10 mL/kg) orally; group 2 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents orally; group 3 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents plus vitamin C (10 mg/kg/day) orally. Six rats in each group were randomly selected and sacrificed on day 20 by cervical dislocation prior to day 21 of gestation, and the foetuses were harvested through abdominal incision for physical examination. Blood samples were collected from the 1st filial rats of the remaining six animals for biochemical and hematological examination. The liver, kidney, heart, and brain of all the sacrificed animals were used for histopathological examination. There were significant (P ≤ 0.05) low birth weights of the foetuses of the animals that were treated with fixed-dose combined antituberculous agents. The haematological parameters also revealed a reduction in the platelets counts and neutrophiles at the first filial generation. Significant (P ≤ 0.05) elevations in the levels of aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the foetuses of the animals treated with fixed-dose combined antituberculous agents were also observed. However, the combination of vitamin C with fixed-dose combined antituberculous agents significantly

  7. Assessing the Risk of Birth Defects Associated with Exposure to Fixed-Dose Combined Antituberculous Agents during Pregnancy in Rats

    Directory of Open Access Journals (Sweden)

    O. Awodele

    2012-01-01

    Full Text Available Due to the risks of disease progression and transmission to the newborn, treatment of tuberculosis is often pursued during pregnancy and fixed-dose combined antituberculous agents have been found to be beneficial. Unfortunately, there is paucity of data on the safety of the fixed-dose combined antituberculous drugs during pregnancy. This study intends to assess the teratogenic effect of fixed-dose combined antituberculous drugs on the organogenesis stage of fetal development and also investigate the possible roles of vitamin C in modulating the teratogenic effects of these agents on the fetus using animal model. Pregnant rats were divided into 3 groups with 12 animals per group: group 1 received distilled water (10 mL/kg orally; group 2 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents orally; group 3 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents plus vitamin C (10 mg/kg/day orally. Six rats in each group were randomly selected and sacrificed on day 20 by cervical dislocation prior to day 21 of gestation, and the foetuses were harvested through abdominal incision for physical examination. Blood samples were collected from the 1st filial rats of the remaining six animals for biochemical and hematological examination. The liver, kidney, heart, and brain of all the sacrificed animals were used for histopathological examination. There were significant (≤0.05 low birth weights of the foetuses of the animals that were treated with fixed-dose combined antituberculous agents. The haematological parameters also revealed a reduction in the platelets counts and neutrophiles at the first filial generation. Significant (≤0.05 elevations in the levels of aspartate aminotransferase (AST and alkaline phosphatase (ALP in the foetuses of the animals treated with fixed-dose combined antituberculous agents were also observed. However, the combination of vitamin C with fixed-dose combined antituberculous agents

  8. Development of computational pregnant female and fetus models and assessment of radiation dose from positron-emitting tracers

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Tianwu [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva (Switzerland); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva (Switzerland); Geneva University, Geneva Neuroscience Center, Geneva (Switzerland); University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University of Southern Denmark, Department of Nuclear Medicine, Odense (Denmark)

    2016-12-15

    Molecular imaging using PET and hybrid (PET/CT and PET/MR) modalities nowadays plays a pivotal role in the clinical setting for diagnosis and staging, treatment response monitoring, and radiation therapy treatment planning of a wide range of oncologic malignancies. The developing embryo/fetus presents a high sensitivity to ionizing radiation. Therefore, estimation of the radiation dose delivered to the embryo/fetus and pregnant patients from PET examinations to assess potential radiation risks is highly praised. We constructed eight embryo/fetus models at various gestation periods with 25 identified tissues according to reference data recommended by the ICRP publication 89 representing the anatomy of the developing embryo/fetus. The developed embryo/fetus models were integrated into realistic anthropomorphic computational phantoms of the pregnant female and used for estimating, using Monte Carlo calculations, S-values of common positron-emitting radionuclides, organ absorbed dose, and effective dose of a number of positron-emitting labeled radiotracers. The absorbed dose is nonuniformly distributed in the fetus. The absorbed dose of the kidney and liver of the 8-week-old fetus are about 47.45 % and 44.76 % higher than the average absorbed dose of the fetal total body for all investigated radiotracers. For {sup 18}F-FDG, the fetal effective doses are 2.90E-02, 3.09E-02, 1.79E-02, 1.59E-02, 1.47E-02, 1.40E-02, 1.37E-02, and 1.27E-02 mSv/MBq at the 8th, 10th, 15th, 20th, 25th, 30th, 35th, and 38th weeks of gestation, respectively. The developed pregnant female/fetus models matching the ICRP reference data can be exploited by dedicated software packages for internal and external dose calculations. The generated S-values will be useful to produce new standardized dose estimates to pregnant patients and embryo/fetus from a variety of positron-emitting labeled radiotracers. (orig.)

  9. Influence of radiation dose and reconstruction algorithm in MDCT assessment of airway wall thickness: A phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Cardona, Daniel [Department of Medical Physics, University of Wisconsin-Madison School of Medicine and Public Health, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States); Nagle, Scott K. [Department of Medical Physics, University of Wisconsin-Madison School of Medicine and Public Health, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States); Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Avenue, Madison, Wisconsin 53792 (United States); Department of Pediatrics, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Avenue, Madison, Wisconsin 53792 (United States); Li, Ke; Chen, Guang-Hong, E-mail: gchen7@wisc.edu [Department of Medical Physics, University of Wisconsin-Madison School of Medicine and Public Health, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States); Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Avenue, Madison, Wisconsin 53792 (United States); Robinson, Terry E. [Department of Pediatrics, Stanford School of Medicine, 770 Welch Road, Palo Alto, California 94304 (United States)

    2015-10-15

    Purpose: Wall thickness (WT) is an airway feature of great interest for the assessment of morphological changes in the lung parenchyma. Multidetector computed tomography (MDCT) has recently been used to evaluate airway WT, but the potential risk of radiation-induced carcinogenesis—particularly in younger patients—might limit a wider use of this imaging method in clinical practice. The recent commercial implementation of the statistical model-based iterative reconstruction (MBIR) algorithm, instead of the conventional filtered back projection (FBP) algorithm, has enabled considerable radiation dose reduction in many other clinical applications of MDCT. The purpose of this work was to study the impact of radiation dose and MBIR in the MDCT assessment of airway WT. Methods: An airway phantom was scanned using a clinical MDCT system (Discovery CT750 HD, GE Healthcare) at 4 kV levels and 5 mAs levels. Both FBP and a commercial implementation of MBIR (Veo{sup TM}, GE Healthcare) were used to reconstruct CT images of the airways. For each kV–mAs combination and each reconstruction algorithm, the contrast-to-noise ratio (CNR) of the airways was measured, and the WT of each airway was measured and compared with the nominal value; the relative bias and the angular standard deviation in the measured WT were calculated. For each airway and reconstruction algorithm, the overall performance of WT quantification across all of the 20 kV–mAs combinations was quantified by the sum of squares (SSQs) of the difference between the measured and nominal WT values. Finally, the particular kV–mAs combination and reconstruction algorithm that minimized radiation dose while still achieving a reference WT quantification accuracy level was chosen as the optimal acquisition and reconstruction settings. Results: The wall thicknesses of seven airways of different sizes were analyzed in the study. Compared with FBP, MBIR improved the CNR of the airways, particularly at low radiation dose

  10. Quantitative analysis of EGR proteins binding to DNA: assessing additivity in both the binding site and the protein

    Directory of Open Access Journals (Sweden)

    Stormo Gary D

    2005-07-01

    Full Text Available Abstract Background Recognition codes for protein-DNA interactions typically assume that the interacting positions contribute additively to the binding energy. While this is known to not be precisely true, an additive model over the DNA positions can be a good approximation, at least for some proteins. Much less information is available about whether the protein positions contribute additively to the interaction. Results Using EGR zinc finger proteins, we measure the binding affinity of six different variants of the protein to each of six different variants of the consensus binding site. Both the protein and binding site variants include single and double mutations that allow us to assess how well additive models can account for the data. For each protein and DNA alone we find that additive models are good approximations, but over the combined set of data there are context effects that limit their accuracy. However, a small modification to the purely additive model, with only three additional parameters, improves the fit significantly. Conclusion The additive model holds very well for every DNA site and every protein included in this study, but clear context dependence in the interactions was detected. A simple modification to the independent model provides a better fit to the complete data.

  11. Diagnostic assessment to estimate and minimize neutron dose rates received by occupationally exposed individuals at cyclotron facilities

    Energy Technology Data Exchange (ETDEWEB)

    Reina, L.C. [Instituto de Engenharia Nuclear, Comissao Nacional de Energia Nuclear, Caixa Postal 68550, Cidade Universitaria, CEP: 21941-906 Rio de Janeiro (Brazil)], E-mail: reina@ien.gov.br; Silva, A.X. [PEN/COPPE-DNC/Escola Politecnica, Universidade Federal do Rio de Janeiro, Cidade Universitaria, CEP: 21945-970 Rio de Janeiro (Brazil); Suita, J.C.; Souza, M.I.S. [Instituto de Engenharia Nuclear, Comissao Nacional de Energia Nuclear, Caixa Postal 68550, Cidade Universitaria, CEP: 21941-906 Rio de Janeiro (Brazil); Facure, A. [Comissao Nacional de Energia Nuclear Rua General Severiano, 90-Botafogo, CEP: 22290-901 Rio de Janeiro (Brazil); Silva, J.C.P.; Furlanetto, J.A.D. [Instituto de Engenharia Nuclear, Comissao Nacional de Energia Nuclear, Caixa Postal 68550, Cidade Universitaria, CEP: 21941-906 Rio de Janeiro (Brazil); Rebello, W. [Instituto Militar de Engenharia, Ministerio da Defesa Praca General Tiburcio, 80-Praia Vermelha, CEP: 22290-270 Rio de Janeiro (Brazil)

    2010-03-15

    Since 2003, radiopharmaceuticals for medical diagnostic purposes have been produced at the Instituto de Engenharia Nuclear, in Brazil, using two cyclotron accelerators - CV-28 and RDS111. As a result of the ever increasing production, a diagnostic assessment to reduce neutron dose rates received by occupationally exposed individuals during irradiation processes has been developed. The purpose of this work is to present this assessment, which is currently being applied to both the Fluorine and Iodine targets of CV-28 and RDS111 cyclotron accelerators.

  12. Assessment of brain dose distribution for ARC and conformal radiation therapy (CRT: A comparison study

    Directory of Open Access Journals (Sweden)

    Tamer Dawod

    2015-01-01

    Conclusion: The tangential beam ARCRT planning demonstrated a significantly better homogeneity index for the GTV, CTV, and PTV of the brain cancer patients with a significant reduction in the mean doses of the both eyes, optic nerves, optic chiasm and brain stem.

  13. Dose assessment to inhalation exposure of indoor 222Rn daughters in Korea.

    Science.gov (United States)

    Ha, C W; Chang, S Y; Lee, B H

    1992-10-01

    Long-term, average indoor 222Rn concentrations were measured in 12 residential areas by passive CR-39 radon cups. Corresponding equilibrium-equivalent concentration of radon daughters were derived. The resulting effective dose equivalent for the Korean population due to inhalation exposure of this equilibrium-equivalent concentration of radon daughters was then evaluated.

  14. Shielding design and dose assessment for accelerator based neutron capture therapy.

    Science.gov (United States)

    Howard, W B; Yanch, J C

    1995-05-01

    Preparations are ongoing to test the viability and usefulness of an accelerator source of epithermal neutrons for ultimate use in a clinical environment. This feasibility study is to be conducted in a shielded room located on the Massachusetts Institute of Technology campus and will not involve patient irradiations. The accelerator production of neutrons is based on the 7Li(p, n)7Be reaction, and a maximum proton beam current of 4 mA at an energy of 2.5 MeV is anticipated. The resultant 3.58 x 10(12) neutrons s-1 have a maximum energy of 800 keV and will be substantially moderated. This paper describes the Monte Carlo methods used to estimate the neutron and photon dose rates in a variety of locations in the vicinity of the accelerator, as well as the shielding configuration required when the device is run at maximum current. Results indicate that the highest absorbed dose rate to which any individual will be exposed is 3 microSv h-1 (0.3 mrem h-1). The highest possible yearly dose is 0.2 microSv (2 x 10(-2) mrem) to the general public or 0.9 mSv (90 mrem) to a radiation worker in close proximity to the accelerator facility. The shielding necessary to achieve these dose levels is also discussed.

  15. A Probabilistic Approach to Uncertainty Analysis in NTPR Radiation Dose Assessments

    Science.gov (United States)

    2009-11-01

    Headquarters (HQ) Detachment, Enewetak Atoll .............................................. 115 5.1.1 Case Description and Cohort Participation Scenario...Administrative and Operations Detachments, Enewetak Atoll .......................... 122 5.2.1 Case Description and Cohort Participation Scenario...Figure 33. Comparison of the Dose Distribution from Probabilistic Analysis with Unbiased Film Badge Readings for the 7126th AU at Enewetak Atoll

  16. DOSE ASSESSMENTS FROM THE DISPOSAL OF LOW-ACTIVITY WASTES IN RCRA-C DISPOSAL CELLS

    Science.gov (United States)

    Modeling the long-term performance of the RCRA-C disposal cell and potential doses to off-site receptors is used to derive maximum radionuclide specific concentrations in the wastes that would enable these wastes to be disposed of safely using the RCRA-C disposal cell technology....

  17. Assessment of {sup 226}Ra age-dependent dose from water intake

    Energy Technology Data Exchange (ETDEWEB)

    Porntepkasemsan, Boonsom [Research and Development Group, Thailand Institute of Nuclear Technology, Vibhavadi Rangsit Road, Bangkok 10900 (Thailand)], E-mail: boonsom@oaep.go.th; Srisuksawad, Kanitha [Research and Development Group, Thailand Institute of Nuclear Technology, Vibhavadi Rangsit Road, Bangkok 10900 (Thailand)

    2008-11-15

    The radioactivity in canal and ground waters collected in a 2-year long observation from the vicinity of the Rare Earth Research and Development Center (RRDC), Phathumthani Province, Thailand, was measured in order to determine the concentration of {sup 226}Ra and to estimate the age-dependent effective dose to humans due to consumption. {sup 226}Ra activities in both canal and ground waters were well below the WHO guidance level for drinking water quality of 1 Bq L{sup -1}. The highest {sup 226}Ra effective doses per year were found for infants and teens. However, the observed levels of calculated {sup 226}Ra effective doses for all age groups in both canal and ground waters show satisfactory low values (less than 15 {mu}Sv yr{sup -1}). These values are acceptable in accordance with the WHO recommended reference dose level of 100 {mu}Sv yr{sup -1} from water intake of 2 L day{sup -1}.

  18. Development of Internal Dose Assessment Program for Nuclear Power Plant Employees

    Energy Technology Data Exchange (ETDEWEB)

    Song, Myung Jae; Kang, Duck Won; Maeng, Sung Jun; Kim, Hee Geun; Son, Soon Whan; Lim, Young Kee; Son, Joong Kwon; Park, Keyoung Rock [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Jang, See Young; Ha, Jong Woo; Suh, Keyoung Won [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Oh, Oak Doo; Lee, Joong Woo; Yoon, Sung Sik [Yonsei University, Seoul (Korea, Republic of)

    1996-12-31

    Internal exposure monitoring based on new concept of radiation protection. Analysis and Performance test of the in vivo systems being operated in nuclear power plants in Korea. Design and fabrication of humanoid phantom for calibration of in vivo system. Development of internal dose evaluation code based on the ICRP 30 dosimetric model. (author). 44 refs., figs.

  19. Assessment of harmfulness of green sand with additions of dust from dry dedusting

    Directory of Open Access Journals (Sweden)

    M. Holtzer

    2010-07-01

    Full Text Available Recently, in the literature about the problems cause to the environment by foundry industry, attention has been paid to the presence and harmful effect of aromatic hydrocarbons: benzene, toluene, ethylbenzene and isomers of xylenes (BTEX and polycyclic aromatic hydrocarbons (PAHs. The growing interest in these pollutants of the environment is a result of their biological activity; some of them are characterized by mutagenic and carcinogenic action. In foundries these hydrocarbons are emitted during the contact between mould or core sands and liquid metal.This article discusses the results of the studies made on the elution rate of some harmful compounds include polycyclic aromatic hydrocarbons (PAHs (Table 3 and 4 from waste mould sand with bentonite and coal dust M1 (mixture Kormix 75 and this one with addition of dust from dry dedusting of sand M2 preparing station (partial replacement of bentonite and emission of BTEX gases from this moulds poured with molten cast iron. From the results given in these tables it follows that both mould sands are characterized by low values of the concentration of investigation substances and haven’t negative influence for environment during casting or management in other means. Tests were done according to the methodology developed at Faculty of Foundry Engineering University of Science and Technology in Cracow.

  20. Bone mineral density assessment using the EOS low-dose X-ray device: a feasibility study.

    Science.gov (United States)

    Sapin, E; Briot, K; Kolta, S; Gravel, P; Skalli, W; Roux, C; Mitton, D

    2008-11-01

    To predict bone strength in the case of osteoporosis, it could be a real benefit to assess the three-dimensional (3D) geometry and the bone mineral density (BMD) with a single low-dose X-ray device, such as the EOS system (Biospace Med, Paris, France). EOS 3D reconstructions of the spine have already been validated. Thus, this study aims at evaluating the accuracy of this low-dose system as a densitometer first ex vivo. The European Spine Phantom (ESP) (number 129) was scanned ten times using both the EOS and a Hologic device (Hologic, Inc., Massachusetts, USA). Accuracy was given by the sum of the systematic error (difference between BMDs assessed and true values given by the phantom manufacturer) and the random error (coefficient of variation). EOS BMDs and Hologic BMDs of 41 ex-vivo vertebrae were calculated and compared. The reproducibility of the method evaluating the EOS BMD was assessed giving the coefficient of variation of three measurements of the 41 vertebrae. The accuracy of the EOS system is below 5.2 per cent, versus 7.2 per cent for the Hologic system in the same conditions. EOS BMDs are significantly higher than Hologic BMDs, but they are strongly correlated. The reproducibility of the method of assessment is equal to 0.95 per cent. The EOS system is accurate for ex-vivo BMD assessments, which is promising regarding the use of this new system to predict vertebral strength.

  1. Assessment of indoor radon doses received by the students in the Azad Kashmir schools, Pakistan.

    Science.gov (United States)

    Rafique, Muhammad; Rahman, S U; Rahman, Said; Matiullah; Shahzad, M Ikram; Ahmed, Navid; Iqbal, Javid; Ahmed, Basharat; Ahmed, Tanveer; Akhtar, Nadeem

    2010-12-01

    Several epidemiological studies conducted on thousands of underground miners suggest that long- term exposure to high radon concentration can increase the risk of lung cancer. Keeping in view the importance of the subject, numerous studies throughout the world have been carried out to measure indoor radon concentration and its resulting doses at occupational and non-occupational sites. The purpose of the current study was to measure indoor radon concentration and its resulting doses received by the students of Azad Kashmir government schools. For this purpose, CR-39 radon detectors were installed in 80 carefully selected schools. The detectors were placed at a height of 3-5 ft. (depending upon average height of students in particular class) from the ground. After exposure of 90 d detectors were etched for 9 h in 6 M NaOH at 70°C and the observed track densities were related to radon concentrations. The measured indoor radon concentration ranged from 22 ± 9 to 228 ± 3 Bq m(-3) with a mean value of 78 ± 5 Bq m(-3). Based on the measured indoor radon data, the annual effective doses were found to vary from 0.55 ± 0.04 to 0.71 ± 0.03 mSv y(-1). The overall mean effective dose for the studied area was found to be 0.63 ± 0.04 mSv y(-1). Reported values for radon concentrations and corresponding doses are lower than ICRP recommended limits for workplaces.

  2. 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) Dose-Response Studies: Preliminary Literature Search Results and Request for Additional Studies

    Science.gov (United States)

    EPA invited the public to comment on the preliminary list of in vivo mammalian dose-response citations for 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD). This list was compiled as a first step in the development of EPA’s response to the National Academy of Sciences comments (NAS, 2...

  3. A randomized controlled dose-response pilot study of addition of hCG to recombinant FSH during controlled ovarian stimulation for in vitro fertilization

    DEFF Research Database (Denmark)

    Loft, A; Egeberg, Anne Noes; Smitz, J;

    2012-01-01

    Is it possible to define an optimal dose of hCG in combination with rFSH from the first day of stimulation in the GnRH agonist protocol applied to IVF? SUMMARY ANSWER: Supplementation with hCG from the first day of stimulation may increase the number of top-quality embryos per patient. Daily doses...... of hCG up to 150 IU are compatible with good live birth rates. A ceiling level of estradiol (E(2)) was reached with hCG doses above 100 IU/day. A positive dose-response was seen for pre-ovulatory progesterone, but concentrations remained below values for which an impairment of endometrial receptivity...... has been previously reported. We suggest a large clinical trial to be proceeded with a group given 100 IU hCG daily versus a control group. WHAT IS KNOWN AND WHAT THIS PAPER ADDS: Prospective multicentre studies have indicated increased live birth rates and increased number of top-quality embryos when...

  4. 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) Dose-Response Studies: Preliminary Literature Search Results and Request for Additional Studies

    Science.gov (United States)

    EPA invited the public to comment on the preliminary list of in vivo mammalian dose-response citations for 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD). This list was compiled as a first step in the development of EPA’s response to the National Academy of Sciences comments (NAS, 2...

  5. Low-dose gamma irradiation following hot Water immersion of Papaya (Carica Papaya linn.) fruits provides additional control of postharvest fungal infection to extend shelf life

    DEFF Research Database (Denmark)

    Rashid, M.H.A.; Grout, Brian William Wilson; Continella, A.

    2015-01-01

    Low-dose gamma irradiation (0.08 kGy over 10 min), a level significantly below that required to satisfy the majority of international quarantine regulations, has been employed to provide a significant reduction in visible fungal infection on papaya fruit surfaces. This is appropriate for local...

  6. Vessel asymmetry as an additional diagnostic tool in the assessment of abdominal aortic aneurysms.

    LENUS (Irish Health Repository)

    Doyle, Barry J

    2009-02-01

    OBJECTIVE: Abdominal aortic aneurysm (AAA) rupture is believed to occur when the local mechanical stress exceeds the local mechanical strength of the wall tissue. On the basis of this hypothesis, the knowledge of the stress acting on the wall of an unruptured aneurysm could be useful in determining the risk of rupture. The role of asymmetry has previously been identified in idealized AAA models and is now studied using realistic AAAs in the current work. METHODS: Fifteen patient-specific AAAs were studied to estimate the relationship between wall stress and geometrical parameters. Three-dimensional AAA models were reconstructed from computed tomography scan data. The stress distribution on the AAA wall was evaluated by the finite element method, and peak wall stress was compared with both diameter and centerline asymmetry. A simple method of determining asymmetry was adapted and developed. Statistical analyses were performed to determine potential significance of results. RESULTS: Mean von Mises peak wall stress +\\/- standard deviation was 0.4505 +\\/- 0.14 MPa (range, 0.3157-0.9048 MPa). Posterior wall stress increases with anterior centerline asymmetry. Peak stress increased by 48% and posterior wall stress by 38% when asymmetry was introduced into a realistic AAA model. CONCLUSION: The relationship between posterior wall stress and AAA asymmetry showed that excessive bulging of one surface results in elevated wall stress on the opposite surface. Assessing the degree of bulging and asymmetry that is experienced in an individual AAA may be of benefit to surgeons in the decision-making process and may provide a useful adjunct to diameter as a surgical intervention guide.

  7. A randomized controlled dose-response pilot study of addition of hCG to recombinant FSH during controlled ovarian stimulation for in vitro fertilization.

    Science.gov (United States)

    Thuesen, L L; Loft, A; Egeberg, A N; Smitz, J; Petersen, J H; Andersen, A Nyboe

    2012-10-01

    Is it possible to define an optimal dose of hCG in combination with rFSH from the first day of stimulation in the GnRH agonist protocol applied to IVF? Supplementation with hCG from the first day of stimulation may increase the number of top-quality embryos per patient. Daily doses of hCG up to 150 IU are compatible with good live birth rates. A ceiling level of estradiol (E(2)) was reached with hCG doses above 100 IU/day. A positive dose-response was seen for pre-ovulatory progesterone, but concentrations remained below values for which an impairment of endometrial receptivity has been previously reported. We suggest a large clinical trial to be proceeded with a group given 100 IU hCG daily versus a control group. Prospective multicentre studies have indicated increased live birth rates and increased number of top-quality embryos when low doses of hCG were associated with FSH. We analysed the clinical, embryological and endocrine aspects of adding increasing doses of hCG to rFSH from the first day of stimulation for IVF. A prospective randomized, controlled, open-label dose-response pilot study was conducted between February 2009 and June 2010 at Copenhagen University Hospital, Rigshospitalet, Denmark. Adequate allocation concealment was assured from sequentially numbered, opaque, sealed envelopes prepared from a computer-generated list. Scoring of the embryos was done in an assessor-blinded way. Endocrinologically normal IVF patients aged 25-37 years, BMI 18-30 kg/m(2), regular cycles and FSH D100; n= 16) and Dose 150 (D150; n= 15). Two patients in D150 were withdrawn after randomization because of major (10- to 30-fold) hCG dosing errors, leaving 13 patients in this group. Thus, the results are based on the per protocol population. The mean numbers of top-quality embryos per patient were D0: 0.8 ± 1.2, D50: 0.5 ± 0.7, D100: 1.2 ± 1.7 and D150: 1.5 ± 1.7 (P= 0.04). All pregnancies were singleton gestations, and the live birth rates per started cycle were D0

  8. Low-dose phase-based X-ray imaging techniques for in situ soft tissue engineering assessments.

    Science.gov (United States)

    Izadifar, Zohreh; Honaramooz, Ali; Wiebe, Sheldon; Belev, George; Chen, Xiongbiao; Chapman, Dean

    2016-03-01

    In tissue engineering, non-invasive imaging of biomaterial scaffolds and tissues in living systems is essential to longitudinal animal studies for assessments without interrupting the repair process. Conventional X-ray imaging is inadequate for use in soft tissue engineering due to the limited absorption difference between the soft tissue and biomaterial scaffolds. X-ray phase-based imaging techniques that derive contrast from refraction or phase effects rather than absorption can provide the necessary contrast to see low-density biomaterial scaffolds and tissues in large living systems. This paper explores and compares three synchrotron phase-based X-ray imaging techniques-computed tomography (CT)-diffraction enhanced imaging (DEI), -analyzer based imaging (ABI), and -phase contrast imaging (PCI)-for visualization and characterization of low-density biomaterial scaffolds and tissues in situ for non-invasive soft tissue engineering assessments. Intact pig joints implanted with polycaprolactone scaffolds were used as the model to assess and compare the imaging techniques in terms of different qualitative and quantitative criteria. For long-term in vivo live animal imaging, different strategies for reducing the imaging radiation dose and scan time-reduced number of CT projections, region of interest, and low resolution imaging-were examined with the presented phase-based imaging techniques. The results demonstrated promising capabilities of the phase-based techniques for visualization of biomaterial scaffolds and soft tissues in situ. The low-dose imaging strategies were illustrated effective for reducing the radiation dose to levels appropriate for live animal imaging. The comparison among the imaging techniques suggested that CT-DEI has the highest efficiency in retaining image contrast at considerably low radiation doses.

  9. Emergency assessment of patients with acute abdominal pain using low-dose CT with iterative reconstruction: a comparative study.

    Science.gov (United States)

    Poletti, Pierre-Alexandre; Becker, Minerva; Becker, Christoph D; Halfon Poletti, Alice; Rutschmann, Olivier T; Zaidi, Habib; Perneger, Thomas; Platon, Alexandra

    2017-08-01

    To determine if radiation dose delivered by contrast-enhanced CT (CECT) for acute abdominal pain can be reduced to the dose administered in abdominal radiography (<2.5 mSv) using low-dose CT (LDCT) with iterative reconstruction algorithms. One hundred and fifty-one consecutive patients requiring CECT for acute abdominal pain were included, and their body mass index (BMI) was calculated. CECT was immediately followed by LDCT. LDCT series was processed using 1) 40% iterative reconstruction algorithm blended with filtered back projection (LDCT-IR-FBP) and 2) model-based iterative reconstruction algorithm (LDCT-MBIR). LDCT-IR-FBP and LDCT-MBIR images were reviewed independently by two board-certified radiologists (Raters 1 and 2). Abdominal pathology was revealed on CECT in 120 (79%) patients. In those with BMI <30, accuracies for correct diagnosis by Rater 1 with LDCT-IR-FBP and LDCT-MBIR, when compared to CECT, were 95.4% (104/109) and 99% (108/109), respectively, and 92.7% (101/109) and 100% (109/109) for Rater 2. In patients with BMI ≥30, accuracies with LDCT-IR-FBP and LDCT-MBIR were 88.1% (37/42) and 90.5% (38/42) for Rater 1 and 78.6% (33/42) and 92.9% (39/42) for Rater 2. The radiation dose delivered by CT to non-obese patients with acute abdominal pain can be safely reduced to levels close to standard radiography using LDCT-MBIR. • LDCT-MBIR (<2.5 mSv) can be used to assess acute abdominal pain. • LDCT-MBIR (<2.5 mSv) cannot safely assess acute abdominal pain in obese patients. • LDCT-IR-FBP (<2.5 mSv) cannot safely assess patients with acute abdominal pain.

  10. Impact of patient positioning on radiotherapy dose distribution: An assessment in parotid tumor

    Directory of Open Access Journals (Sweden)

    Seema Sharma

    2016-03-01

    Full Text Available Purpose: We intended to study the impact of patient positioning on the dose distribution within target volume and organs at risk in patients with parotid malignancies treated with 3D conformal radiotherapy (3D-CRT with photon wedge pair (WP or intensity modulated radiotherapy (IMRT.Methods: Three patients with a non-Hodgkin’s lymphoma of the right parotid gland were consecutively immobilized using thermoplastic cast in 2 positions: supine with head in neutral position (HN and with head turned 90° to the left side (HT. Images for treatment planning purpose were acquired in both positions. For both positions, photon WP plans and 5 field IMRT plans were generated, after contouring clinical target volume (CTV, planning target volume (PTV= CTV + 5 mm margin and organs at risk (OAR. All plans were evaluated for target coverage and dose to OARs.Results: Both CTV and PTV were apparently larger in HN compared with HT (31.76±8.89 cc, 30.31±7.83 cc and 62.49±19.01 cc, 58.89±15.33 cc respectively. The CI value for PTV was slightly better for HT compared to HN position in both the WP and IMRT plans. The homogeneity was comparable in both the head positions in case of WP plan. The mean HI of PTV was increased in case of IMRT plan at HT versus HN position (1.108 vs. 1.097. A change in head position from HN to HT with wedge pair plan resulted in a reduction of brainstem Dmax and Dmean. Lesser dose was observed in HN position for contralateral parotid. A difference of 0.9 Gy in the average Dmax to spinal cord was seen. The values of Dmean to mandible, oral cavity, ipsilateral and contralateral cochlea were higher in the HT position. A change in head position from HN to HT with IMRT plan resulted in a dose reduction in average Dmax to brainstem. The spinal cord Dmax increased at the HT position by 1.2 Gy. The dose to contralateral parotid and cochlea was comparable in both the positions. However, the Dmean to oral cavity was reduced at HT position. Whereas

  11. Assessment of equivalent dose on the lens in cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, M. V. L.; Campos, P. S. F. [Federal University of Bahia, Department of Health Sciences, Salvador (Brazil); Andrade, M. E. A. [Federal University of Pernambuco, Department of Nuclear Energy, Recife (Brazil); Soares, M. R. [Federal University of Sergipe, Department of Physics, Sao Cristovao (Brazil); Batista, W. O., E-mail: marcusradiology@gmail.com [Federal Institute of Bahia, Department of Applied Sciences, 40.301-015 Salvador (Brazil)

    2014-08-15

    The Cone Beam Computed Tomography (CBCT) is presented as a useful test method for the evaluation of craniofacial structures. Among them stands the temporomandibular joint (T MJ) imaging as complementary to clinical evaluation. It must be considered that there is no reference levels established for diagnosis of this imaging modality. In this same context, recently the limit for crystalline lens was reviewed by ICRP which set new values to the equivalent dose. The aim of this study was to evaluate the kerma at the surface of the crystalline lens in T MJ CBCT and derive the equivalent dose. It was used an anthropomorphic phantom of the head and neck (manufactured by: Radiation Support Devices, model; Rs-230) containing equivalent tissue with dimensions of a typical patient. The dosimetric measurements were obtained by using seven pairs of thermoluminescent dosimetry (TLD) dosimeters (LiF: Mg, Ti) positioned on the surface of the crystalline lens, divided into two pairs (one pair for each eye) per scanner evaluated. The tomographic images were obtained in three CBCT equipment s (Kodak 9000, Gendex GXCB 500 and i-Cat). Values of equivalent dose obtained were: 5.82 mSv (Kodak 9000); 5.38 mSv (Gendex GXCB 500) and 7.98 mSv (i-Cat). These results demonstrate that for this type of procedure the doses are below the annual limit but may vary in accordance with the scanner and the exposure factors used in the image acquisition. The Gendex GXCB500 uses larger Fov and higher kV. It results in levels close to those obtained on Kodak 9000. Larger doses are associated with the i-Cat. Another factor that rises is the repetition of examinations due to positioning errors and / or patient movement, which may exceed the annual limit established by ICRP. Although the ICRP limits are not applied to medical exposures, it is advisable to consider the sensitivity of the organ. For this reason, it is concluded that doses per T MJ procedure on CBCT are below the annual limit and may vary

  12. Assessment of annual average effective dose status in the cohort of medical staff in Lithuania during 1991-2013.

    Science.gov (United States)

    Samerdokiene, Vitalija; Mastauskas, Albinas; Atkocius, Vydmantas

    2015-12-01

    The use of radiation sources for various medical purposes is closely related to irradiation of the medical staff, which causes harmful effects to health and an increased risk of cancer. In total, 1463 medical staff who have been occupationally exposed to sources of ionising radiation (IR) had been monitored. Records with annual dose measurements (N = 19 157) were collected and regularly analysed for a 23-y period: from 01 January 1991 to 31 December 2013. The collected annual average effective dose (AAED) data have been analysed according to different socio-demographic parameters and will be used in future investigation in order to assess cancer risk among medical staff occupationally exposed to sources of IR. A thorough analysis of data extracted from medical staff's dose records allows one to conclude that the average annual effective dose of Lithuanian medical staff occupationally exposed to sources of IR was consistently decreased from 1991 (1.75 mSv) to 2013 (0.27 mSv) (p < 0.0001).

  13. Natural radioactivities in iron and nickel ores imported into Japan and the dose assessment for workers handling them.

    Science.gov (United States)

    Iwaoka, Kazuki; Tagami, Keiko; Yonehara, Hidenori

    2010-09-01

    Japan imports Fe and Ni ores from abroad for use as industrial raw materials in the manufacture of industrial products like stainless steel. Some of these ores might contain high levels of radioactivity, and then workers handling them would be exposed to radiation without being aware of it. Activity concentrations in these ores should be measured to evaluate the radiation exposure of workers. In this study, Fe and Ni ores used as industrial raw materials were collected from iron and steel companies, and the activity concentrations of the (238)U series, the (232)Th series and (40)K in these ores were determined using inductively coupled plasma mass spectrometry (ICP-MS) and gamma ray spectrometry. The activity concentrations of the (238)U series, the (232)Th series and (40)K in these ores samples were lower than the International Atomic Energy Agency (IAEA) values. The doses to workers handling these ores were estimated using methods for dose assessment given in a report by the European Commission. In each scenario, a maximum value of the annual effective dose to workers was estimated to be about 6.8 × 10(-6) Sv, which was lower than intervention exemption levels (annual dose 1.0 × 10(-3) Sv) given in International Commission on Radiological Protection (ICRP) Publication 82.

  14. Natural radioactivities in iron and nickel ores imported into Japan and the dose assessment for workers handling them

    Energy Technology Data Exchange (ETDEWEB)

    Iwaoka, Kazuki; Tagami, Keiko; Yonehara, Hidenori, E-mail: iwaoka@nirs.go.j [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)

    2010-09-15

    Japan imports Fe and Ni ores from abroad for use as industrial raw materials in the manufacture of industrial products like stainless steel. Some of these ores might contain high levels of radioactivity, and then workers handling them would be exposed to radiation without being aware of it. Activity concentrations in these ores should be measured to evaluate the radiation exposure of workers. In this study, Fe and Ni ores used as industrial raw materials were collected from iron and steel companies, and the activity concentrations of the {sup 238}U series, the {sup 232}Th series and {sup 40}K in these ores were determined using inductively coupled plasma mass spectrometry (ICP-MS) and gamma ray spectrometry. The activity concentrations of the {sup 238}U series, the {sup 232}Th series and {sup 40}K in these ores samples were lower than the International Atomic Energy Agency (IAEA) values. The doses to workers handling these ores were estimated using methods for dose assessment given in a report by the European Commission. In each scenario, a maximum value of the annual effective dose to workers was estimated to be about 6.8 x 10{sup -6} Sv, which was lower than intervention exemption levels (annual dose 1.0 x 10{sup -3} Sv) given in International Commission on Radiological Protection (ICRP) Publication 82. (note)

  15. Integration of Fiber-Reinforced Polymers in a Life Cycle Assessment of Injection Molding Process Chains with Additive Manufacturing

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Bey, Niki; Mischkot, Michael

    2017-01-01

    Additive manufacturing technologies applied to injection molding process chain have acquired an increasingly important role in the context of tool inserts production, especially by vat polymerization. Despite the decreased lifetime during their use in the injection molding process, the inserts come...... with improvements in terms of production time, costs, exibility, as well as potentially improved environmental performance as compared to conventional materials in a life cycle perspective.This contribution supports the development of additively manufactured injection molding inserts with the use of fiber......-reinforced vat polymerization technology. The life cycle assessment of the prototyping process chain for rapid prototyping with high exibility provides a base for industrial applications in injection molding....

  16. Use of DandD for dose assessment under NRC`s radiological criteria for license termination rule

    Energy Technology Data Exchange (ETDEWEB)

    Gallegos, D.P.; Brown, T.J.; Davis, P.A. [Sandia National Labs., Albuquerque, NM (United States). Environmental Risk and Decision Analysis Dept.; Daily, C. [Nuclear Regulatory Commission, Washington, DC (United States)

    1998-05-01

    The Decontamination and Decommissioning (DandD) software package has been developed by Sandia National Laboratories for the Nuclear Regulatory Commission (NRC) specifically for the purpose of providing a user-friendly analytical tool to address the dose criteria contained in NRC`s Radiological Criteria for License Termination rule (10 CFR Part 20 Subpart E; NRC, 1997). Specifically, DandD embodies the NRC`s screening methodology to allow licensees to convert residual radioactivity contamination levels at their site to annual dose, in a manner consistent with both 10 CFR Part 20 and the corresponding implementation guidance developed by NRC. The screening methodology employs reasonably conservative scenarios, fate and transport models, and default parameter values that have been developed to allow the NRC to quantitatively estimate the risk of releasing a site given only information about the level of contamination. Therefore, a licensee has the option of specifying only the level of contamination and running the code with the default parameter values, or in the case where site specific information is available to alter the appropriate parameter values and then calculate dose. DandD can evaluate dose for fur different scenarios: residential, building occupancy, building renovation, or drinking water. The screening methodology and DandD are part of a larger decision framework that allows and encourages licensees to optimize decisions on choice of alternative actions at their site, including collection of additional data and information. This decision framework is integrated into and documented in NRC`s technical guidance for decommissioning.

  17. ASSESSMENT OF THE AVERAGE ANNUAL EFFECTIVE DOSES FOR THE INHABITANTS OF THE SETTLEMENTS LOCATED IN THE TERRITORIES CONTAMINATED DUE TO THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    N. G. Vlasova

    2012-01-01

    Full Text Available Catalogue of the average annual effective exposure doses of the inhabitants of the territories contaminated due to the Chernobul accident had been developed according to the method of the assessment of the average annual effective exposure doses of the settlements inhabitants. The cost-efficacy of the use of the average annual effective dose assessment method was 250 000 USD for the current 5 years. Average annual effective dose exceeded 1 mSv/year for 191 Belarus settlements from 2613. About 50 000 persons are living in these settlements.

  18. Absorbed dose assessment in particle-beam irradiated metal-oxide and metal-nonmetal memristors

    Directory of Open Access Journals (Sweden)

    Knežević Ivan D.

    2012-01-01

    Full Text Available Absorbed dose was estimated after Monte Carlo simulation of proton and ion beam irradiation on metal-oxide and metal-nonmetal memristors. A memristive device comprises two electrodes, each of a nanoscale width, and a double-layer active region disposed between and in electrical contact with electrodes. Following materials were considered for the active region: titanium dioxide, zirconium dioxide, hafnium dioxide, strontium titanium trioxide and galium nitride. Obtained results show that significant amount of oxygen ion - oxygen and nonmetal ion - nonmetal vacancy pairs is to be generated. The loss of such vacancies from the device is believed to deteriorate the device performance over time. Estimated absorbed dose values in the memristor for different constituting materials are of the same order of magnitude because of the close values of treshold displacement energies for the investigated materials.

  19. A collimated detection system for assessing leakage dose from medical linear accelerators at the patient plane.

    Science.gov (United States)

    Lonski, P; Taylor, M L; Franich, R D; Kron, T

    2014-03-01

    Leakage radiation from linear accelerators can make a significant contribution to healthy tissue dose in patients undergoing radiotherapy. In this work thermoluminescent dosimeters (LiF:Mg,Cu,P TLD chips) were used in a focused lead cone loaded with TLD chips for the purpose of evaluating leakage dose at the patient plane. By placing the TLDs at one end of a stereotactic cone, a focused measurement device is created; this was tested both in and out of the primary beam of a Varian 21-iX linac using 6 MV photons. Acrylic build up material of 1.2 cm thickness was used inside the cone and measurements made with either one or three TLD chips at a given distance from the target. Comparing the readings of three dosimeters in one plane inside the cone offered information regarding the orientation of the cone relative to a radiation source. Measurements in the patient plane with the linac gantry at various angles demonstrated that leakage dose was approximately 0.01% of the primary beam out of field when the cone was pointed directly towards the target and 0.0025% elsewhere (due to scatter within the gantry). No specific 'hot spots' (e.g., insufficient shielding or gaps at abutments) were observed. Focused cone measurements facilitate leakage dose measurements from the linac head directly at the patient plane and allow one to infer the fraction of leakage due to 'direct' photons (along the ray-path from the bremsstrahlung target) and that due to scattered photons.

  20. Radiation Dose Assessments for Fleet-Based Individuals in Operation Tomodachi, Revision 1

    Science.gov (United States)

    2014-04-01

    ships were not included in this report. In other cases, some ships were included despite being located outside the 200 nautical-mile (nmi) radius ...was included although it was well outside the 200 nmi radius from FDNPS during the two-month time period. The Seventh Fleet comprises 60–70 ships...the cosmic 37 radiation dose. Although these detection systems respond to the combined influence of all sources listed above, from the plots some

  1. Radiation Dose Assessments for Fleet-Based Individuals in Operation Tomodachi

    Science.gov (United States)

    2013-09-01

    report. In other cases, some ships were included despite being located outside the 200 nautical-mile (nmi) radius from the FDNPS because the OTR...well outside the 200 nmi radius from FDNPS during the two-month time period. The Seventh Fleet comprises 60–70 ships, 200–300 aircraft, and 40,000 Navy...surfaces. As discussed in the shore-based report, the MEXT systems did not quantify most of the cosmic radiation dose. Although these detection

  2. Assessment of Concentration and the Annual Effective Dose of Radon Gas in Imam Hospital Indoor Air

    Directory of Open Access Journals (Sweden)

    Kobra Verijkazemi

    2016-09-01

    Full Text Available Introduction and purpose: Exposure to natural sources of radiation, especially radon and its short-term products, is an important issue around the world. Radon exposure causes lung cancer in humans. Therefore, the aim of this study was to measure the concentration of radon gas and its annual effective dose in Imam Hospital of Tehran, Iran and to compare its concentrations with the recommended standards. Methods: Radon levels and meteorological parameters (temperature, pressure, and moisture were measured in different levels and in four seasons, using Radstar and Lutron Electronic devices, respectively, during June 2014-June 2015. The collected data were analyzed through SPSS 18. Annual effective dose was calculated, using the equation for annual effective dose introduced by Scientific Committee of the United Nations. Results: The highest concentration of radon and annual effective dose were observed in the winter, which were 82/15 Bq/m3 and0/48 ms/y, respectively. Furthermore, concerning the various levels, the highest concentration was observed in the lowest level (56/1 Bq/m3.Conclusion: The results of the current study demonstrated that radon concentration was lower than the standards set by Environmental Protection Agency and World Health Organization. Regarding this, there are not concerns about the possible dangers of radon gas activities for the personnel and patients of the hospital. 

  3. Radiation Dose Assessments for the Embryo, Fetus, and Nursing Infant during Operation Tomodachi

    Science.gov (United States)

    2013-08-01

    of breastfeeding by artificially choosing an effective intake time before or after the actual intake time (ICRP, 2004). However, because the total...milk; (3) used the DCs for the three month old infant for the entire nursing period; and, (4) assumed six months of breastfeeding starting at zero...weaning. The ICRP DCs, despite being based on a six-month duration of breastfeeding , can be used for estimating the doses from longer or shorter periods

  4. Radiation Dose Assessments for Shore-Based Individuals in Operation Tomodachi, Revision 1

    Science.gov (United States)

    2012-12-31

    Prefecture City Shore Location Hokkaido Sapporo Shiga Otsu Aomori Aomori Misawa AB Kyoto Kyoto Iwate Morioka City of Ofunato* Osaka Osaka Miyagi Sendai...unlikely to have consumed food and water from non-DOD sources (i.e., by eating on the local economy near their assigned locations in Japan...purposes, eating on the local economy one day per week for the first month (a total of 4 days), the highest doses would have been calculated for a 1

  5. Radiometric modeling through the combined use of the EDR gamma scanner and the VISIPLAN dose assessment tool

    Energy Technology Data Exchange (ETDEWEB)

    Perez, J.M. [Laboratoria General de Electronica y Automatica, CIEMAT, Edificio 22, Avenida Complutense 22, E-28040 Madrid (Spain)]. E-mail: jm.perez@ciemat.es; Vermeersch, F. [SCK-CEN, Boeretang 200, 2400 Mol (Belgium); Vela, O. [Laboratoria General de Electronica y Automatica, CIEMAT, Edificio 22, Avenida Complutense 22, E-28040 Madrid (Spain); Burgos, E. de [Laboratoria General de Electronica y Automatica, CIEMAT, Edificio 22, Avenida Complutense 22, E-28040 Madrid (Spain)

    2004-11-11

    In this paper, we present the work performed on the integration of a new gamma scanner prototype, known as EDR, with a 3D-dose assessment software tool called VISIPLAN. It is one of the first approaches to merge gamma imaging instrumentation and a 3D-dose assessment program into a combined operative hardware-software solution for the characterization of a site in the field of radiation protection. The main features of the scanner design are presented here, together with a representative part of the tests performed during its characterization. The EDR directional sensitivity is determined for two gamma radiation fields originating from {sup 137}Cs and {sup 60}Co sources and forms the basis for the interpretation of the gamma scans using VISIPLAN. The combination of a 3D-source model and the detailed instrument response function can determine the source activities from the gamma scans, and also enables in a second step, the simulation of the dose-rate field on the site. The integration of the two tools was tested in a laboratory and validated in an industrial facility.

  6. Assessment of knowledge and awareness among radiology personnel regarding current computed tomography technology and radiation dose

    Science.gov (United States)

    Karim, M. K. A.; Hashim, S.; Bradley, D. A.; Bahruddin, N. A.; Ang, W. C.; Salehhon, N.

    2016-03-01

    In this paper, we evaluate the level of knowledge and awareness among 120 radiology personnel working in 7 public hospitals in Johor, Malaysia, concerning Computed Tomography (CT) technology and radiation doses based on a set of questionnaires. Subjects were divided into two groups (Medical profession (Med, n=32) and Allied health profession (AH, n=88). The questionnaires are addressed: (1) demographic data (2) relative radiation dose and (3) knowledge of current CT technology. One-third of respondents from both groups were able to estimate relative radiation dose for routine CT examinations. 68% of the allied health profession personnel knew of the Malaysia regulations entitled ‘Basic Safety Standard (BSS) 2010’, although notably 80% of them had previously attended a radiation protection course. No significant difference (p < 0.05) in mean scores of CT technology knowledge detected between the two groups, with the medical professions producing a mean score of (26.7 ± 2.7) and the allied health professions a mean score of (25.2 ± 4.3). This study points to considerable variation among the respondents concerning their understanding of knowledge and awareness of risks of radiation and CT optimization techniques.

  7. Assessment of Annual Effective Dose for Natural Radioactivity of Gamma Emitters in Biscuit Samples in Iraq.

    Science.gov (United States)

    Abojassim, Ali Abid; Al-Alasadi, Lubna A; Shitake, Ahmed R; Al-Tememie, Faeq A; Husain, Afnan A

    2015-09-01

    Biscuits are an important type of food, widely consumed by babies in Iraq and other countries. This work uses gamma spectroscopy to measure the natural radioactivity due to long-lived gamma emitters in children's biscuits; it also estimates radiation hazard indices, that is, the radium equivalent activity, the representative of gamma level index, the internal hazard index, and the annual effective dose in children. Ten samples were collected from the Iraqi market from different countries of origin. The average specific activities for (226)Ra, (232)Th, and (40)K were 9.390, 3.1213, and 214.969 Bq/kg, respectively, but the average of the radium equivalent activity and the internal hazard index were 33.101 Bq/kg and 0.107, respectively. The total average annual effective dose from consumption by adults, children, and infants is estimated to be 0.655, 1.009, and 0.875 mSv, respectively. The values found for specific activity, radiation hazard indices, and annual effective dose in all samples in this study were lower than worldwide median values for all groups; therefore, these values are found to be safe.

  8. Postremediation dose assessment for the Elza Gate site, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Nimmagadda, M.; Yu, C.

    1993-03-01

    Potential maximum radiation dose rates were calculated for the Elza Gate site in Oak Ridge, Tennessee. The RESRAD computer code, which implements the methodology described in the US Department of Energy's manual for implementing residual radioactive material guidelines, was used in this evaluation. Currently, the site is not being used. Four potential future use scenarios were considered for the Elza Gate site; the scenarios vary with regard to time spent at the site, sources of water used, and sources of food consumed. In Scenario A (the expected scenario), industrial use of the site is assumed; in Scenario B (a plausible scenario), recreational use of the site is assumed. Both Scenarios C and D (possible but unlikely scenarios) assume the presence of a resident farmer in the immediate vicinity of the site. The difference between Scenarios C and D is the source of water used. For Scenario C, an adjacent pond provides 100% of the water for drinking, irrigation, and raising livestock; for Scenario D, groundwater drawn from a well located at the downgradient edge of the contaminated zone is the only source of water for drinking, investigation, and raising livestock. The results of the evaluation indicate that the US Department of Energy dose limit of 100 mrem/yr would not be exceeded for any scenario. The potential maximum dose rates for Scenarios A, B, C, and D are 1.5, 0.66, 12, and 42 mrem/yr, respectively.

  9. Postremediation dose assessment for the Elza Gate site, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Nimmagadda, M.; Yu, C.

    1993-03-01

    Potential maximum radiation dose rates were calculated for the Elza Gate site in Oak Ridge, Tennessee. The RESRAD computer code, which implements the methodology described in the US Department of Energy`s manual for implementing residual radioactive material guidelines, was used in this evaluation. Currently, the site is not being used. Four potential future use scenarios were considered for the Elza Gate site; the scenarios vary with regard to time spent at the site, sources of water used, and sources of food consumed. In Scenario A (the expected scenario), industrial use of the site is assumed; in Scenario B (a plausible scenario), recreational use of the site is assumed. Both Scenarios C and D (possible but unlikely scenarios) assume the presence of a resident farmer in the immediate vicinity of the site. The difference between Scenarios C and D is the source of water used. For Scenario C, an adjacent pond provides 100% of the water for drinking, irrigation, and raising livestock; for Scenario D, groundwater drawn from a well located at the downgradient edge of the contaminated zone is the only source of water for drinking, investigation, and raising livestock. The results of the evaluation indicate that the US Department of Energy dose limit of 100 mrem/yr would not be exceeded for any scenario. The potential maximum dose rates for Scenarios A, B, C, and D are 1.5, 0.66, 12, and 42 mrem/yr, respectively.

  10. Natural radioactivity, dose assessment and uranium uptake by agricultural crops at Khan Al-Zabeeb, Jordan

    Energy Technology Data Exchange (ETDEWEB)

    Al-Kharouf, Samer J. [Royal Scientific Society, Amman 11941 (Jordan); Al-Hamarneh, Ibrahim F. [Prince Abdullah Bin Ghazi Faculty of Science and IT, Al-Balqa Applied University (BAU), Salt 19117 (Jordan)], E-mail: hamarnehibrahim@yahoo.com; Dababneh, Munir [Prince Abdullah Bin Ghazi Faculty of Science and IT, Al-Balqa Applied University (BAU), Salt 19117 (Jordan)

    2008-07-15

    Khan Al-Zabeeb, an irrigated cultivated area lies above a superficial uranium deposits, is regularly used to produce vegetables and fruits consumed by the public. Both soil and plant samples collected from the study area were investigated for their natural radioactivity to determine the uranium uptake by crops and hence to estimate the effective dose equivalent to human consumption. Concentrations of {sup 238}U, {sup 235}U, {sup 232}Th, {sup 226}Ra, {sup 222}Rn, {sup 137}Cs and {sup 40}K in nine soil profiles were measured by gamma-ray spectrometry whereas watermelon and zucchini crops were analyzed for their uranium content by means of alpha spectrometry after radiochemical separation. Correlations between measured radionuclides were made and their activity ratios were determined to evaluate their geochemical behavior in the soil profiles. Calculated soil-plant transfer factors indicate that the green parts (leaves, stems and roots) of the studied crops tend to accumulate uranium about two orders of magnitude higher than the fruits. The maximum dose from ingestion of 1 kg of watermelon pulp was estimated to be 3.1 and 4.7 nSv y{sup -1} for {sup 238}U and {sup 234}U, respectively. Estimations of the annual effective dose equivalent due to external exposure showed extremely low values. Radium equivalent activity and external hazard index were seen to exceed the permissible limits of 370 Bq kg{sup -1} and 1, respectively.

  11. {sup 137}Cs and {sup 210}Po dose assessment from marine food in Cienfuegos Bay (Cuba)

    Energy Technology Data Exchange (ETDEWEB)

    Alonso-Hernandez, C. E-mail: carlos@ceac.perla.inf.cu; Diaz-Asencio, M.; Munos-Caravaca, A.; Suarez-Morell, E.; Avila-Moreno, R

    2002-07-01

    One part of Radiological Monitoring Programme in central Cuba (1991-1995) was dedicated to study the background levels of natural and anthropogenic radioactivity in Cienfuegos Bay in the vicinity of the first Cuban nuclear power station under construction. {sup 210}Po and {sup 137}Cs concentrations in fish, molluscs and crustaceans collected in Cienfuegos Bay were determined and the committed effective doses (CED) were calculated for two population groups inhabiting this region. The highest values of {sup 210}Po concentrations were found in crustaceans, but significant accumulation was also observed in fish and molluscs. The mean {sup 137}Cs concentrations in organisms are several times lower with respect to {sup 210}Po, a situation that characterises the regions affected by the global fallout only. Values of CED from the consumption of crustaceans and molluscs are very low both from{sup 210}Po and {sup 137}Cs. The mean individual dose from {sup 210}Po in the seafood consumed varies from 39 {mu}Sv for general populations to 2802 {mu}Sv for the 'critical group' consuming 320 kg of fish per year. The dose from {sup 137}Cs is negligible.

  12. MODARIA WG5: Towards a practical guidance for including uncertainties in the results of dose assessment of routine releases

    Energy Technology Data Exchange (ETDEWEB)

    Mora, Juan C. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas - CIEMAT (Spain); Telleria, Diego [International Atomic Energy Agency - IAEA (Austria); Al Neaimi, Ahmed [Emirates Nuclear Energy Corporation - ENEC (United Arab Emirates); Blixt Buhr, Anna Ma [Vattenfall AB (Sweden); Bonchuk, Iurii [Radiation Protection Institute - RPI (Ukraine); Chouhan, Sohan [Atomic Energy of Canada Limited - AECL (Canada); Chyly, Pavol [SE-VYZ (Slovakia); Curti, Adriana R. [Autoridad Regulatoria Nuclear - ARN (Argentina); Da Costa, Dejanira [Instituto de Radioprotecao e Dosimetria - IRD (Brazil); Duran, Juraj [VUJE Inc (Slovakia); Galeriu, Dan [Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN-HH (Romania); Haegg, Ann- Christin; Lager, Charlotte [Swedish Radiation Safety Authority - SSM (Sweden); Heling, Rudie [Nuclear Research and Consultancy Group - NRG (Netherlands); Ivanis, Goran; Shen, Jige [Ecometrix Incorporated (Canada); Iosjpe, Mikhail [Norwegian Radiation Protection Authority - NRPA (Norway); Krajewski, Pawel M. [Central Laboratory for Radiological Protection - CLOR (Poland); Marang, Laura; Vermorel, Fabien [Electricite de France - EdF (France); Mourlon, Christophe [Institut de Radioprotection et de Surete Nucleaire - IRSN (France); Perez, Fabricio F. [Belgian Nuclear Research Centre - SCK (Belgium); Woodruffe, Andrew [Federal Authority for Nuclear Regulation - FANR (United Arab Emirates); Zorko, Benjamin [Jozef Stefan Institute (Slovenia)

    2014-07-01

    MODARIA (Modelling and Data for Radiological Impact Assessments) project was launched in 2012 with the aim of improving the capabilities in radiation dose assessment by means of acquisition of improved data for model testing, model testing and comparison, reaching consensus on modelling philosophies, approaches and parameter values, development of improved methods and exchange of information. The project focuses on areas where uncertainties remain in the predictive capability of environmental models, emphasizing in reducing associated uncertainties or developing new approaches to strengthen the evaluation of the radiological impact. Within MODARIA, four main areas were defined, one of them devoted to Uncertainty and Variability. In this area four working groups were included, Working Group 5 dealing with the 'uncertainty and variability analysis for assessments of radiological impacts arising from routine discharges of radionuclides'. Whether doses are estimated by using measurement data, by applying models, or through a combination of measurements and calculations, the variability and uncertainty contribute to a distribution of possible values. The degree of variability and uncertainty is represented by the shape and extent of that distribution. The main objective of WG5 is to explore how to consider uncertainties and variabilities in the results of assessment of doses in planned situations for controlling the impact of routine releases from radioactive and nuclear installations to the environment. The final aim is to produce guidance for the calculation of uncertainties in these exposure situations and for the presentation of such results to the different stakeholders. To achieve that objective the main tasks identified were: to find tools and methods for uncertainty and variability analysis applicable to dose assessments in routine radioactive discharges, to define scenarios where information on uncertainty and variability of parameters is available

  13. Additional notes on clinical repeated-dose pharmacokinetic trials applying a peak-and-trough sampling design to estimate oral clearance.

    Science.gov (United States)

    Takaai, Mari; Kayano, Yuichiro; Shimizu, Takako; Taguchi, Masato; Hashimoto, Yukiya

    2008-01-01

    In the previous study, we performed a simulation of a clinical pharmacokinetic trial, in which blood was sampled at two time points corresponding to the peak concentration (C(peak)) and trough concentration (C(trough)) following repetitive oral administration at the dose, D, and dosing interval, tau. The approximate oral clearance (CL/F(approx)), estimated as 2 x D/(C(peak) x tau+C(trough) x tau), is accurate for drugs with an elimination half-life comparative to or longer than tau; however, it was suggested that we might not use CL/F(approx) for drugs with a considerably short elimination half-life relative to tau. In the present study, we evaluated the accuracy of the alternative oral clearance (CL/F(exp)) estimated by the simple monoexponential model. In contrast to CL/F(approx), CL/F(exp) was accurate for drugs with a short elimination half-life relative to tau. The present finding in conjunction with our previous study suggested that the peak-and-trough sampling design is promising for the clinical repeated-dose pharmacokinetic trial for drugs with not only slow but also rapid elimination from the body. We think that the accuracy and precision of the two analysis methods to estimate oral clearance (CL/F(approx) and CL/F(exp)) for a target drug should be evaluated carefully before and after a real clinical trial.

  14. Risk assessment of nitrate and petroleum-derived hydrocarbon addition on Contricriba weissflogii biomass, lifetime, and nutritional value.

    Science.gov (United States)

    Shun-Xing, Li; Feng-Jiao, Liu; Feng-Ying, Zheng; Xu-Guang, Huang; Yue-Gang, Zuo

    2014-03-15

    Coastal diatoms are often exposed to both petroleum-derived hydrocarbon pollution and eutrophication. How these exposures influence on algal biomass, lifetime, and nutritional value are unknown. To examine a more accurate risk assessment of the pollutants on the role of diatoms in coastal ecosystem functions, Conticribra weissflogii was maintained at different concentrations of nitrate (N) and/or water-soluble fractions of No.0 diesel oil (WSF). Algal density, cell growth cycle, protein, chlorophyll a, superoxide dismutase (SOD) activity, and malonaldehyde (MDA) were determined for the assessment of algal biomass, lifetime, nutritional value, photosynthesis and respiration, antioxidant capacity, and lipid peroxidation, respectively.When N addition was combined with WSF pollution, the cell growth cycles were shortened by 27-44%; SOD activities were decreased by 1-64%; algal density, the concentrations of chlorophyll a, protein, and MDA were varied between 38 and 310%, 62 and 712%, 4 and 124%, and 19 and 233% of the values observed in N addition experiments, respectively. Coastal ecosystem functions were severely weakened by N and WSF additions, and the influence was increased in the order: Nassessment of petroleum-derived hydrocarbon on coastal ecosystem functions.

  15. Evaluation of the Comet Assay for Assessing the Dose-Response Relationship of DNA Damage Induced by Ionizing Radiation

    Directory of Open Access Journals (Sweden)

    Qiang Liu

    2013-11-01

    Full Text Available Dose- and time-response curves were combined to assess the potential of the comet assay in radiation biodosimetry. The neutral comet assay was used to detect DNA double-strand breaks in lymphocytes caused by γ-ray irradiation. A clear dose-response relationship with DNA double-strand breaks using the comet assay was found at different times after irradiation (p < 0.001. A time-response relationship was also found within 72 h after irradiation (p < 0.001. The curves for DNA double-strand breaks and DNA repair in vitro of human lymphocytes presented a nice model, and a smooth, three-dimensional plane model was obtained when the two curves were combined.

  16. Objective Assessment of Sunburn and Minimal Erythema Doses: Comparison of Noninvasive In Vivo Measuring Techniques after UVB Irradiation

    Directory of Open Access Journals (Sweden)

    Lo Pei-Yu

    2010-01-01

    Full Text Available Military personnel movement is exposed to solar radiation and sunburn is a major problem which can cause lost workdays and lead to disciplinary action. This study was designed to identify correlation parameters in evaluating in vivo doses and epidermis changes following sunburn inflammation. Several noninvasive bioengineering techniques have made objective evaluations possible. The volar forearms of healthy volunteers ( , 2 areas, 20 mm in diameter, were irradiated with UVB 100 mj/ and 200 mj/ , respectively. The skin changes were recorded by several monitored techniques before and 24 hours after UV exposures. Our results showed that chromameter value provides more reliable information and can be adopted with mathematical model in predicting the minimal erythema dose (MED which showed lower than visual assessment by 10 mj/ (Pearson correlation coefficient . A more objective measure for evaluation of MED was established for photosensitive subjects' prediction and sunburn risks prevention.

  17. Development and operation of the network system for nuclear safety - Improvement of the following accident dose assessment system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Enn Han; Han, Moon Hee; Suh, Kyung Suk; Hwang, Won Tae [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-12-01

    The FADAS has been updates for calculating the real-time wind fields continuously at the nuclear sites in Korea. The system has been constructed to compute the wind fields using its own process for the dummy meteorological data, and does not effect on the overall wind field module. If the radioactive materials are released into the atmosphere in real situation, the calculations of wind fields and exposure dose in the previous FADAS are performed in the case of the recognition of the above situation in the source term evaluation module. The current version of FADAS includes the program for evaluating the effect of the predicted accident and the assumed scenario together. The dose assessment module is separated into the real-time and the supposed accident respectively. 8 refs., 17 figs., 10 tabs. (Author)

  18. Assessment of shoulder position variation and its impact on IMRT and VMAT doses for head and neck cancer

    Directory of Open Access Journals (Sweden)

    Neubauer Emily

    2012-02-01

    Full Text Available Abstract Background For radiotherapy of the head and neck, 5-point mask immobilization is used to stabilize the shoulders. Still, the daily position of the shoulders during treatment may be different from the position in the treatment plan despite correct isocenter setup. The purpose of this study was to determine the interfractional displacement of the shoulders relative to isocenter over the course of treatment and the associated dosimetric effect of this displacement. Methods The extent of shoulder displacements relative to isocenter was assessed for 10 patients in 5-point thermoplastic masks using image registration and daily CT-on-rails scans. Dosimetric effects on IMRT and VMAT plans were evaluated in Pinnacle based on simulation CTs modified to represent shoulder shifts between 3 and 15 mm in the superior-inferior, anterior-posterior, and right-left directions. The impact of clinically observed shoulder shifts on the low-neck dose distributions was examined. Results Shoulder motion was 2-5 mm in each direction on average but reached 20 mm. Superior shifts resulted in coverage loss, whereas inferior shifts increased the dose to the brachial plexus. These findings were generally consistent for both IMRT and VMAT plans. Over a course of observed shifts, the dose to 99% of the CTV decreased by up to 101 cGy, and the brachial plexus dose increased by up to 72 cGy. Conclusions he position of the shoulder affects target coverage and critical structure dose, and may therefore be a concern during the setup of head and neck patients, particularly those with low neck primary disease.

  19. Assessment of shoulder position variation and its impact on IMRT and VMAT doses for head and neck cancer

    Science.gov (United States)

    2012-01-01

    Background For radiotherapy of the head and neck, 5-point mask immobilization is used to stabilize the shoulders. Still, the daily position of the shoulders during treatment may be different from the position in the treatment plan despite correct isocenter setup. The purpose of this study was to determine the interfractional displacement of the shoulders relative to isocenter over the course of treatment and the associated dosimetric effect of this displacement. Methods The extent of shoulder displacements relative to isocenter was assessed for 10 patients in 5-point thermoplastic masks using image registration and daily CT-on-rails scans. Dosimetric effects on IMRT and VMAT plans were evaluated in Pinnacle based on simulation CTs modified to represent shoulder shifts between 3 and 15 mm in the superior-inferior, anterior-posterior, and right-left directions. The impact of clinically observed shoulder shifts on the low-neck dose distributions was examined. Results Shoulder motion was 2-5 mm in each direction on average but reached 20 mm. Superior shifts resulted in coverage loss, whereas inferior shifts increased the dose to the brachial plexus. These findings were generally consistent for both IMRT and VMAT plans. Over a course of observed shifts, the dose to 99% of the CTV decreased by up to 101 cGy, and the brachial plexus dose increased by up to 72 cGy. Conclusions he position of the shoulder affects target coverage and critical structure dose, and may therefore be a concern during the setup of head and neck patients, particularly those with low neck primary disease. PMID:22316381

  20. Biological transformation, kinetics and dose-response assessments of bound musk ketone hemoglobin adducts in rainbow trout as biomarkers of environmental exposure

    Institute of Scientific and Technical Information of China (English)

    M A Mottaleb; J H Zimmerman; T W Moy

    2008-01-01

    Low levels (ng/g) of musk ketone (MK), used as a fragrance additive in the formulation of personal care products, are frequently detected in the water and other environment. Thus, aquatic organisms can be continuously exposed to MK. In this study, kinetics and dose-response assessments of 2-amino-MK (AMK) metabolite, bound to cysteine-hemoglobin (Hb) in rainbow trout, formed by enzymatic nitro-reduction of MK have been demonstrated. Trout were exposed to a single exposure of 0.010, 0.030, 0.10, and or 0.30 mg MK/g of fish. Twenty-six Hb samples were collected from exposed- and control fish subsequent to exposure intervals of 1 d (24 h), 3 d (72 h), and 7 d (168 h). Basic hydrolysis released bound AMK metabolite was extracted into n-hexane and then concentrated and analyzed by gas chromatography (GC) electron capture negative ion chemical ionization (NICI) mass spectrometry (MS) using selected ion monitoring (SIM). The presence of the AMK metabolite in Hb extracts was confirmed by agreement of similar mass spectral features and retention time with a standard. In the dose-response study, maximum adduct formation was obtained at the 0.10 mg/g dose with an average AMK metabolite concentration of 2.2 ng/g. For kinetics, the highest concentration of the AMK metabolite was found to be 32.0 ng/g at 0.03 mg/g dose in 3-d sample. Further elimination of the metabolite showed kinetics with a half-life estimated to be 2 d, assuming first-order kinetics. The metabolite was not detected in the control samples, non-hydrolyzed Hb, and reagent blank extracts. The detection limit for AMK in the Hb was approximately 0.30 (g/L, based on a signal to noise ratio of 3 (S/N = 3).

  1. Dose Assessment of Cefquinome by Pharmacokinetic/Pharmacodynamic Modeling in Mouse Model of Staphylococcus aureus Mastitis

    Science.gov (United States)

    Yu, Yang; Zhou, Yu-Feng; Li, Xiao; Chen, Mei-Ren; Qiao, Gui-Lin; Sun, Jian; Liao, Xiao-Ping; Liu, Ya-Hong

    2016-01-01

    This work aimed to characterize the mammary gland pharmacokinetics of cefquinome after an intramammary administration and integrate pharmacokinetic/pharmacodynamic model. The pharmacokinetic profiles of cefquinome in gland tissue were measured using high performance liquid chromatograph. Therapeutic regimens covered various dosages ranging from 25 to 800 μg/gland and multiple dosing intervals of 8, 12, and 24 h. The in vivo bacterial killing activity elevated when dosage increased or when dosing intervals were shortened. The best antibacterial effect was demonstrated by a mean 1.5 log10CFU/gland visible count reduction. On the other hand, the results showed that the percentage of time duration of drug concentration exceeding the MIC during a dose interval (%T > MIC) was generally 100% because of the influence of drug distribution caused by the blood-milk barrier. Therefore, pharmacokinetic/pharmacodynamic parameter of the ratio of area under the concentration-time curve over 24 h to the MIC (AUC0-24/MIC) was used to describe the efficacy of cefquinome instead of %T > MIC. When the magnitude of AUC0-24/MIC exceeding 16571.55 h⋅mL/g, considerable activity of about 1.5 log10CFU/g gland bacterial count reduction was observed in vivo. Based on the Monte Carlo simulation, the clinical recommended regimen of three infusions of 75 mg per quarter every 12 h can achieve a 76.67% cure rate in clinical treatment of bovine mastitis caused by Staphylococcus aureus infection. PMID:27774090

  2. Assessment of dose due to exposure to indoor radon and thoron progeny

    Directory of Open Access Journals (Sweden)

    Prasad Ganesh

    2010-01-01

    Full Text Available The components of the effective dose through inhalation from radon and its progeny are important for human health since they contribute to more than 50% of the total radiation dose from natural sources. As a consequence, radon has been identified as the second leading cause of lung cancer after smoking. Radon and its short lived decay products (218Po, 214Pb, 214Bi, 214Po present in dwellings are a radiation hazard, particularly if such sources are concentrated in the enclosed areas like poorly ventilated houses and underground mines. The indoor radon, thoron, and progeny concentrations were measured in a small hilly town of Budhakedar and the surrounding area of Tehri Garhwal, India, by using LR-115 Type II plastic track detector in a twin cup radon dosimeter. The concentrations of radon progeny were measured as the highest in winter and the lowest in summer while the thoron progeny concentration was found maximum in rainy season and minimum in autumn. The annual exposure to the potential alpha energy of radon and thoron were found to vary from 0.04 WLM to 0.69 WLM with an average value of 0.29 WLM, and 0.03 WLM to 0.37 WLM with an aver- age value of 0.16 WLM, respectively. The annual effective dose due to the exposure to indoor radon and progeny in Budhakedar homes was found to vary from 0.16 mSv to 2.72 mSv with an average value of 1.14 mSv and the effective dose due to the exposure to thoron and progeny was found to vary from 0.18 mSv to 2.49 mSv with an average value of 1.05 mSv. The results of systematic study have been obtained by considering the room as a space in which the radon and thoron levels are directly related to the dynamic and static parameters.

  3. Assessment of image quality and dose calculation accuracy on kV CBCT, MV CBCT, and MV CT images for urgent palliative radiotherapy treatments.

    Science.gov (United States)

    Held, Mareike; Cremers, Florian; Sneed, Penny K; Braunstein, Steve; Fogh, Shannon E; Nakamura, Jean; Barani, Igor; Perez-Andujar, Angelica; Pouliot, Jean; Morin, Olivier

    2016-03-08

    A clinical workflow was developed for urgent palliative radiotherapy treatments that integrates patient simulation, planning, quality assurance, and treatment in one 30-minute session. This has been successfully tested and implemented clinically on a linac with MV CBCT capabilities. To make this approach available to all clin-ics equipped with common imaging systems, dose calculation accuracy based on treatment sites was assessed for other imaging units. We evaluated the feasibility of palliative treatment planning using on-board imaging with respect to image quality and technical challenges. The purpose was to test multiple systems using their commercial setup, disregarding any additional in-house development. kV CT, kV CBCT, MV CBCT, and MV CT images of water and anthropomorphic phantoms were acquired on five different imaging units (Philips MX8000 CT Scanner, and Varian TrueBeam, Elekta VersaHD, Siemens Artiste, and Accuray Tomotherapy linacs). Image quality (noise, contrast, uniformity, spatial resolution) was evaluated and compared across all machines. Using individual image value to density calibrations, dose calculation accuracies for simple treatment plans were assessed for the same phantom images. Finally, image artifacts on clinical patient images were evaluated and compared among the machines. Image contrast to visualize bony anatomy was sufficient on all machines. Despite a high noise level and low contrast, MV CT images provided the most accurate treatment plans relative to kV CT-based planning. Spatial resolution was poorest for MV CBCT, but did not limit the visualization of small anatomical structures. A comparison of treatment plans showed that monitor units calculated based on a prescription point were within 5% difference relative to kV CT-based plans for all machines and all studied treatment sites (brain, neck, and pelvis). Local dose differences > 5% were found near the phantom edges. The gamma index for 3%/3 mm criteria was ≥ 95% in most

  4. The influence of various doses of phosphorus and of the addition of calcium or potassium fertilization upon the yield of tomatoes in Wrocław hydroponic culture using two intensities of light

    Directory of Open Access Journals (Sweden)

    Z. Gumicka

    2013-12-01

    Full Text Available Two experiments were carried out with phosphate fertilization of tomatoes in hydroponic culture. It has been proved that an additional dose of phosphorus given during the second cluster bloom, caused an yield increase. The optimal dose is 12 g of superphosphate (16% P2O5 per plant. The "green back" symptoms did not appear in these conditions. The parallel additional applying of calcium or potassium gave a decrease of the yield. When the light intensity was lowered to about 50%, the yield has decreased by half. In these conditions an additional applying of calcium (0,4 g CaCO3 and phosphorus (1g superphosphate annulated the negative influence of the low light intensity.

  5. Measurement of naturally occurring radionuclides in geothermal samples and assessment of radiological risks and radiation doses.

    Science.gov (United States)

    Parmaksiz, A

    2013-12-01

    The analysis of (226)Ra, (232)Th and (40)K radionuclides has been carried out in geothermal water and residue samples collected from six wells of geothermal power plant and disposal site, using gamma-spectrometry system equipped with a high-purity germanium detector. The activity concentrations of nine geothermal water samples were found to be lower than minimum detectable activity (MDA) values. The activity concentration of the residue samples ranged from 40 ± 4 to 2694 ± 85 Bq kg(-1) for (226)Ra, 33 ± 4 to 2388 ± 85 Bq kg(-1) for (232)Th, and MDA value to 967 ± 30 Bq kg(-1) for (40)K. In the study, some radiological indexes were examined and found to be higher than the reference values for majority of the residue samples. The annual effective doses arising from some residue samples were calculated to be higher than the permitted dose rate for the public, i.e. 1 mSv y(-1).

  6. Indoor radon concentrations and assessment of doses in four districts of the Punjab Province - Pakistan.

    Science.gov (United States)

    Ur-Rahman, Saeed; Rafique, Muhammad; Matiullah; Anwar, Javaid

    2009-11-01

    Seasonal indoor radon measurement studies have been carried out in four districts, namely, Jhelum, Chakwal, Rawalpindi and Attock of the Punjab Province. In this regard, CR-39 based detectors were installed in bedrooms, drawing rooms and kitchens of 40 randomly selected houses in each district. After exposing to radon in each season, CR-39 detectors were etched in 6M NaOH at 80 degrees C and counted under an optical microscope. Indoor radon activity concentrations in the houses surveyed ranged from 15 +/- 4 to 176 +/- 7 Bq m(-3) with an overall average value of 55 +/- 31 Bq m(-3). The observed annual average values are greater than the world average of 40 Bq m(-3). Maximum indoor radon concentration levels were observed in winter season whereas minimum levels were observed in summer season. None of the measured radon concentration value exceeded the action level of 200-400 Bq m(-3). The season/annual ratios for different type of dwellings varied from 0.87 +/- 0.93 to 1.14 +/- 1.10. The mean annual estimated effective dose received by the residents of the studied area was found to be 1.39 +/- 0.78 mSv. The annual estimated effective dose is less than the recommended action level (3-10 mSv).

  7. Evaluation of a low-dose CT protocol with oral contrast for assessment of acute appendicitis