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Sample records for postal dosimetric system

  1. Dosimetric characteristics of fabricated silica fibre for postal radiotherapy dose audits

    NASA Astrophysics Data System (ADS)

    Fadzil, M. S. Ahmad; Ramli, N. N. H.; Jusoh, M. A.; Kadni, T.; Bradley, D. A.; Ung, N. M.; Suhairul, H.; Mohd Noor, N.

    2014-11-01

    Present investigation aims to establish the dosimetric characteristics of a novel fabricated flat fibre TLD system for postal radiotherapy dose audits. Various thermoluminescence (TL) properties have been investigated for five sizes of 6 mol% Ge-doped optical fibres. Key dosimetric characteristics including reproducibility, linearity, fading and energy dependence have been established. Irradiations were carried out using a linear accelerator (linac) and a Cobalt-60 machine. For doses from 0.5 Gy up to 10 Gy, Ge-doped flat fibres exhibit linearity between TL yield and dose, reproducible to better than 8% standard deviation (SD) following repeat measurements (n = 3). For photons generated at potentials from 1.25 MeV to 10 MV an energy-dependent response is noted, with a coefficient of variation (CV) of less than 40% over the range of energies investigated. For 6.0 mm length flat fibres 100 μm thick × 350 pm wide, the TL fading loss following 30 days of storage at room temperature was < 8%. The Ge-doped flat fibre system represents a viable basis for use in postal radiotherapy dose audits, corrections being made for the various factors influencing the TL yield.

  2. Developing and improving a scanning system for dosimetric applications

    SciTech Connect

    Perez, P.; Galvan, V.; Castellanoa, G.; Valente, M.

    2010-08-04

    Radiotherapy is nowadays one of the most used techniques for the treatment of different pathologies, particularly cancer diseases. The accuracy regarding the application of these treatments, which are planned according to patient information, depends mainly on the dosimetric measurements of absorbed dose within irradiated tissues. The present work is devoted to the study, design and construction of an original device capable of performing visible light transmission measurements in order to analyze Fricke gel dosimeters. Furthermore, a suitable bi-dimensional positioning system along with a dedicated control system and image processing software has been adapted to the dosimetric device in order to perform 2D dose mapping. The obtained results confirm the feasibility of the proposed method, therefore suggesting its potentiality for clinical applications.

  3. Dosimetric precision of an ion beam tracking system

    PubMed Central

    2010-01-01

    Background Scanned ion beam therapy of intra-fractionally moving tumors requires motion mitigation. GSI proposed beam tracking and performed several experimental studies to analyse the dosimetric precision of the system for scanned carbon beams. Methods A beam tracking system has been developed and integrated in the scanned carbon ion beam therapy unit at GSI. The system adapts pencil beam positions and beam energy according to target motion. Motion compensation performance of the beam tracking system was assessed by measurements with radiographic films, a range telescope, a 3D array of 24 ionization chambers, and cell samples for biological dosimetry. Measurements were performed for stationary detectors and moving detectors using the beam tracking system. Results All detector systems showed comparable data for a moving setup when using beam tracking and the corresponding stationary setup. Within the target volume the mean relative differences of ionization chamber measurements were 0.3% (1.5% standard deviation, 3.7% maximum). Film responses demonstrated preserved lateral dose gradients. Measurements with the range telescope showed agreement of Bragg peak depth under motion induced range variations. Cell survival experiments showed a mean relative difference of -5% (-3%) between measurements and calculations within the target volume for beam tracking (stationary) measurements. Conclusions The beam tracking system has been successfully integrated. Full functionality has been validated dosimetrically in experiments with several detector types including biological cell systems. PMID:20591160

  4. Dosimetric evaluation of a three-dimensional treatment planning system

    PubMed Central

    Murugan, Appasamy; Valas, Xavier Sidonia; Thayalan, Kuppusamy; Ramasubramanian, Velayudham

    2011-01-01

    The computerized treatment planning system plays a major role in radiation therapy in delivering correct radiation dose to the patients within ±5% as recommended by the ICRU. To evaluate the dosimetric performance of the Treatment Planning system (TPS) with three-dimensional dose calculation algorithm using the basic beam data measured for 6 MV X-rays. Eleven numbers of test cases were created according to the Technical Report Series-430 (TRS 430) and are used to evaluate the TPS in a homogeneous water phantom. These cases involve simple field arrangements as well as the presence of a low-density material in the beam to resemble an air in-homogeneity. Absolute dose measurements were performed for the each case with the MU calculation given by the TPS, and the measured dose is compared with the corresponding TPS calculated dose values. The result yields a percentage difference maximum of 2.38% for all simple test cases. For complex test cases in the presence of in-homogeneity, beam modifiers or beam modifiers with asymmetric fields a maximum percentage difference of 5.94% was observed. This study ensures that the dosimetric calculations performed by the TPS are within the accuracy of ±5% which is very much warranted in patient dose delivery. The test procedures are simple, not only during the installation of TPS, but also repeated at periodic intervals. PMID:21430854

  5. [Improved program maintenance of the CIRCIS dosimetric planning system].

    PubMed

    Sevast'ianov, A I; Liutova, N A; Ratner, T G

    1983-03-01

    A special computer complex CIRCIS (Informatique, France) is used in the All-Union Cancer Research Center, USSR AMS, for the dosimetric planning of radiotherapy on 5 gamma-beam units and electron accelerator. Mathematical maintenance of the complex includes programs of the calculation of dose distribution for gamma-, inhibition and electron radiation but has no program of the calculation of the time of irradiation. The authors have devised and introduced into the complex such a program in the Fortran language that makes it possible to calculate within 2-3 min the time of irradiation for multifield rotation therapy using several units as a time, thus expediting the dosimetric planning for patients' irradiation.

  6. Bedside rationing by general practitioners: A postal survey in the Danish public healthcare system

    PubMed Central

    Lauridsen, Sigurd MR; Norup, Michael; Rossel, Peter

    2008-01-01

    Background It is ethically controversial whether medical doctors are morally permitted to ration the care of their patients at the bedside. To explore whether general practitioners in fact do ration in this manner we conducted a study within primary care in the Danish public healthcare system. The purpose of the study was to measure the extent to which general practitioners (GPs) would be willing to factor in cost-quality trade-offs when prescribing medicine, and to discover whether, and if so to what extent, they believe that patients should be informed about this. Methods Postal survey of 600 randomly selected Danish GPs, of which 330 responded to the questionnaire. The Statistical Package for the Social Sciences (SPSS, version 14.0) was used to produce general descriptive statistics. Significance was calculated with the McNemar and the chi-square test. The main outcome measures of the study were twofold: an assessment of the proportion of GPs who, in a mainly hypothetical setting, would consider cost-quality trade-offs relevant to their clinical decision-making given their economic impact on the healthcare system; and a measure of the extent to which they would disclose this information to patients. Results In the hypothetical setting 95% of GPs considered cost-quality trade-offs relevant to their clinical decision-making given the economic impact of such trade-offs on the healthcare system. In all 90% stated that this consideration had been relevant in clinical decision-making within the last month. In the hypothetical setting 55% would inform their patients that they considered a cost-quality trade-off relevant to their clinical decisions given the economic impact of such trade-offs on the healthcare system. The most common reason (68%) given for not wanting to inform patients about this matter was the belief that the information would not prove useful to patients. In the hypothetical setting cost-quality trade-offs were considered relevant significantly more

  7. System for integrated interstitial photodynamic therapy and dosimetric monitoring

    NASA Astrophysics Data System (ADS)

    Johansson, Ann; Soto Thompson, Marcelo; Johansson, Thomas; Bendsoe, Niels; Svanberg, Katarina; Svanberg, Sune; Andersson-Engels, Stefan

    2005-04-01

    Photodynamic therapy for the treatment of cancer relies on the presence of light, sensitizer and oxygen. By monitoring these three parameters during the treatment a better understanding and treatment control could possibly be achieved. Here we present data from in vivo treatments of solid skin tumors using an instrument for interstitial photodynamic therapy with integrated dosimetric monitoring. By using intra-tumoral ALA-administration and interstitial light delivery solid tumors are targeted. The same fibers are used for measuring the fluence rate at the treatment wavelength, the sensitizer fluorescence and the local blood oxygen saturation during the treatment. The data presented is based on 10 treatments in 8 patients with thick basal cell carcinomas. The fluence rate measurements at 635 nm indicate a major treatment induced absorption increase, leading to a limited light penetration at the treatment wavelength. This leads to a far from optimal treatment since the absorption increase prevents peripheral tumor regions from being fully treated. An interactive treatment has been implemented assisting the physician in delivering the correct light dose. The absorption increase can be compensated for by either prolonging the treatment time or increasing the output power of each individual treatment fiber. The other parameters of importance, i.e. the sensitizer fluorescence at 705 nm and the local blood oxygen saturation, are monitored in order to get an estimate of the amount of photobleaching and oxygen consumption. Based on the oxygen saturation signal, a fractionized irradiation can be introduced in order to allow for a re-oxygenation of the tissue.

  8. Application of a radiophotoluminescent glass dosimeter to nonreference condition dosimetry in the postal dose audit system

    SciTech Connect

    Mizuno, Hideyuki Fukumura, Akifumi; Fukahori, Mai; Sakata, Suoh; Yamashita, Wataru; Takase, Nobuhiro; Yajima, Kaori; Katayose, Tetsurou; Abe-Sakama, Kyoko; Kanai, Tatsuaki; Kusano, Yohsuke; Shimbo, Munefumi

    2014-11-01

    Purpose: The purpose of this study was to obtain a set of correction factors of the radiophotoluminescent glass dosimeter (RGD) output for field size changes and wedge insertions. Methods: Several linear accelerators were used for irradiation of the RGDs. The field sizes were changed from 5 × 5 cm to 25 × 25 cm for 4, 6, 10, and 15 MV x-ray beams. The wedge angles were 15°, 30°, 45°, and 60°. In addition to physical wedge irradiation, nonphysical (dynamic/virtual) wedge irradiations were performed. Results: The obtained data were fitted with a single line for each energy, and correction factors were determined. Compared with ionization chamber outputs, the RGD outputs gradually increased with increasing field size, because of the higher RGD response to scattered low-energy photons. The output increase was about 1% per 10 cm increase in field size, with a slight difference dependent on the beam energy. For both physical and nonphysical wedged beam irradiation, there were no systematic trends in the RGD outputs, such as monotonic increase or decrease depending on the wedge angle change if the authors consider the uncertainty, which is approximately 0.6% for each set of measured points. Therefore, no correction factor was needed for all inserted wedges. Based on this work, postal dose audits using RGDs for the nonreference condition were initiated in 2010. The postal dose audit results between 2010 and 2012 were analyzed. The mean difference between the measured and stated doses was within 0.5% for all fields with field sizes between 5 × 5 cm and 25 × 25 cm and with wedge angles from 15° to 60°. The standard deviations (SDs) of the difference distribution were within the estimated uncertainty (1SD) except for the 25 × 25 cm field size data, which were not reliable because of poor statistics (n = 16). Conclusions: A set of RGD output correction factors was determined for field size changes and wedge insertions. The results obtained from recent postal dose

  9. Three dimensional dose verification of VMAT plans using the Octavius 4D dosimetric system

    NASA Astrophysics Data System (ADS)

    Arumugam, Sankar; Xing, Aitang; Young, Tony; Thwaites, David; Holloway, Lois

    2015-01-01

    The Octavius 4D dosimetric system generates a 3D dose matrix based on a measured planar dose and user supplied Percentage Depth Dose (PDD) data. The accuracy of 3D dose matrices reconstructed by the Octavius 4D dosimetric system was systematically studied for an open static field, an open arc field and clinical VMAT plans. The Octavius reconstructed 3D dose matrices were compared with the Treatment Planning System (TPS) calculated 3D dose matrices using 3D gamma (γ) analysis with 2%/2mm and 3%/3mm tolerance criteria. The larger detector size in the 2D detector array of the Octavius system resulted in failed voxels in the high dose gradient regions. For the open arc fields mean (1σ) γ pass rates of 84.5(8.9) % and 94.2(4.5) % were observed with 2%/2mm and 3%/3mm tolerance criteria respectively and for clinical VMAT plans mean (1σ) γ pass rates of 86.8(3.5) % and 96.7(1.4) % were observed.

  10. Dosimetric Considerations in Radioimmunotherapy and Systemic Radionuclide Therapies: A Review

    PubMed Central

    Loke, Kelvin S. H.; Padhy, Ajit K.; Ng, David C. E.; Goh, Anthony S.W.; Divgi, Chaitanya

    2011-01-01

    Radiopharmaceutical therapy, once touted as the “magic bullet” in radiation oncology, is increasingly being used in the treatment of a variety of malignancies; albeit in later disease stages. With ever-increasing public and medical awareness of radiation effects, radiation dosimetry is becoming more important. Dosimetry allows administration of the maximum tolerated radiation dose to the tumor/organ to be treated but limiting radiation to critical organs. Traditional tumor dosimetry involved acquiring pretherapy planar scans and plasma estimates with a diagnostic dose of intended radiopharmaceuticals. New advancements in single photon emission computed tomography and positron emission tomography systems allow semi-quantitative measurements of radiation dosimetry thus allowing treatments tailored to each individual patient. PMID:22144871

  11. Dosimetric validation of a commercial Monte Carlo based IMRT planning system

    SciTech Connect

    Grofsmid, Dennis; Dirkx, Maarten; Marijnissen, Hans; Woudstra, Evert; Heijmen, Ben

    2010-02-15

    Purpose: Recently a commercial Monte Carlo based IMRT planning system (Monaco version 1.0.0) was released. In this study the dosimetric accuracy of this new planning system was validated. Methods: Absolute dose profiles, depth dose curves, and output factors calculated by Monaco were compared with measurements in a water phantom. Different static on-axis and off-axis fields were tested at various source-skin distances for 6, 10, and 18 MV photon beams. Four clinical IMRT plans were evaluated in a water phantom using a linear diode detector array and another six IMRT plans for different tumor sites in solid water using a 2D detector array. In order to evaluate the accuracy of the dose engine near tissue inhomogeneities absolute dose distributions were measured with Gafchromic EBT film in an inhomogeneous slab phantom. For an end-to-end test a four-field IMRT plan was applied to an anthropomorphic lung phantom with a simulated tumor peripherally located in the right lung. Gafchromic EBT film, placed in and around the tumor area, was used to evaluate the dose distribution. Results: Generally, the measured and the calculated dose distributions agreed within 2% dose difference or 2 mm distance-to-agreement. But mainly at interfaces with bone, some larger dose differences could be observed. Conclusions: Based on the results of this study, the authors concluded that the dosimetric accuracy of Monaco is adequate for clinical introduction.

  12. 76 FR 49511 - Postal Service Initiative on Retail Postal Locations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... the Federal Register of August 4, 2011, FR Doc. 2011-19725, on page 47276, in the Procedural Schedule... Postal Service Initiative on Retail Postal Locations AGENCY: Postal Regulatory Commission. ACTION: Notice... of the continuation of service at postal retail locations. The procedural schedule included...

  13. 39 CFR 762.15 - Postal Service payments not made by disbursement postal money order.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... postal money order. 762.15 Section 762.15 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS General, Definitions, Issuance § 762.15 Postal Service payments not made by disbursement postal money order. Postal Service...

  14. 39 CFR 762.15 - Postal Service payments not made by disbursement postal money order.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... postal money order. 762.15 Section 762.15 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS General, Definitions, Issuance § 762.15 Postal Service payments not made by disbursement postal money order. Postal Service...

  15. Technical note: evaluation of dosimetric performance in a commercial 3D treatment planning system.

    PubMed

    Sandilos, P; Seferlis, S; Antypas, C; Karaiskos, P; Dardoufas, C; Vlahos, L

    2005-10-01

    The aim of this work was to evaluate the dosimetric performance of a commercial treatment planning system (TPS) which employs a three-dimensional calculation algorithm (Nucletron Plato version 2.2.3), following the guidelines of the AAPM Task Group 23 (TG23). Seven test cases were used to test the TPS dosimetric performance in homogeneous water. These cases involved absolute dose measurements on central as well as off-axis points situated at various depths, using simple field arrangements, and comparison with corresponding TPS calculations. This comparison yielded differences within +/-2% at all points, for all test cases. To test the ability of the TPS to account for tissue inhomogeneities, corresponding comparisons were performed with the presence of a low-density material in the beam to resemble an air inhomogeneity. Absolute dose measurements and corresponding TPS calculations showed a mean deviation of the order of +/-3.5%, reaching a maximum of 11.5% for small field sizes (5 cm x 5 cm). In summary, observed deviations are well within the set tolerance levels while comparison with previous TPS versions showed that Plato version 2.2.3 is significantly improved, especially in dose calculations in the presence of low density inhomogeneities. PMID:16177012

  16. Commissioning of a motion system to investigate dosimetric consequences due to variability of respiratory waveforms.

    PubMed

    Cetnar, Ashley J; James, Joshua; Wang, Brain

    2016-01-08

    A commercially available six-dimensional (6D) motion system was assessed for accuracy and clinical use in our department. Positional accuracy and respiratory waveform reproducibility were evaluated for the motion system. The system was then used to investigate the dosimetric consequences of respiratory waveform variation when an internal target volume (ITV) approach is used for motion management. The maximum deviations are 0.3 mm and 0.22° for translation and rotation accuracy, respectively, for the tested clinical ranges. The origin reproducibility is less than±0.1 mm. The average differences are less than 0.1 mm with a maximum standard deviation of 0.8 mm between waveforms of actual patients and replication of those waveforms by HexaMotion for three breath-hold and one free-breathing waveform. A modified gamma analysis shows greater than 98% agreement with a 0.5 mm and 100 ms threshold. The motion system was used to investigate respiratory waveform variation and showed that, as the amplitude of the treatment waveform increases above that of the simulation waveform, the periphery of the target volume receives less dose than expected. However, by using gating limits to terminate the beam outside of the simulation amplitude, the results are as expected dosimetrically. Specifically, the average dose difference in the periphery between treating with the simulation waveform and the larger amplitude waveform could be up to 12% less without gating limits, but only differed 2% or less with the gating limits in place. The general functionality of the system performs within the manufacturer's specifications and can accurately replicate patient specific waveforms. When an ITV approach is used for motion management, we found the use of gating limits that coincide with the amplitude of the patient waveform at simulation helpful to prevent the potential underdosing of the target due to changes in patient respiration.

  17. 75 FR 80859 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is...). The Postal Service contemporaneously filed a contract related to the proposed new product pursuant...

  18. 75 FR 80857 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is...). The Postal Service contemporaneously filed a contract related to the proposed new product pursuant...

  19. 75 FR 80860 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is...). The Postal Service contemporaneously filed a contract related to the proposed new product pursuant...

  20. 76 FR 11532 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: This document addresses a recent Postal Service filing concerning an additional International Business Reply Service...

  1. 77 FR 37077 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-20

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is...). The Postal Service contemporaneously filed a redacted contract related to the proposed new product....

  2. 76 FR 9055 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-16

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... new requirement. \\1\\ Notice of the United States Postal Service of Classification Change Related...

  3. 75 FR 65533 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-25

    ... From the Federal Register Online via the Government Publishing Office ] POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission... Postal Service contemporaneously filed a contract related to the proposed new product pursuant to 39...

  4. 78 FR 29784 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-21

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice SUMMARY: The Commission is noticing a recent Postal Service filing concerning the addition of Global Expedited Package Services...

  5. 75 FR 27375 - Postal Rate Case Management

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-14

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION Postal Rate Case Management AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is seeking comments relevant to management of an anticipated exigent postal rate case. It...

  6. 78 FR 70969 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-27

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing recent Postal Service filings requesting the addition of Priority Mail Contract 67 to...

  7. 78 FR 70967 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-27

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing recent Postal Service filings requesting the addition of Priority Mail Contract 70 to...

  8. 78 FR 79509 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-30

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning an additional Global Expedited Package Services (GEPS)...

  9. 78 FR 70968 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-27

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing recent Postal Service filings requesting the addition of Priority Mail Contract 69 to...

  10. 78 FR 79508 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-30

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning an additional Global Expedited Package Services (GEPS)...

  11. 78 FR 70970 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-27

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing recent Postal Service filings requesting the addition of Priority Mail Contract 68 to...

  12. Comparison of the dose distribution obtained from dosimetric systems with intensity modulated radiotherapy planning system in the treatment of prostate cancer

    NASA Astrophysics Data System (ADS)

    Gökçe, M.; Uslu, D. Koçyiǧit; Ertunç, C.; Karalı, T.

    2016-03-01

    The aim of this study is to compare Intensity Modulated Radiation Therapy (IMRT) plan of prostate cancer patients with different dose verification systems in dosimetric aspects and to compare these systems with each other in terms of reliability, applicability and application time. Dosimetric control processes of IMRT plan of three prostate cancer patients were carried out using thermoluminescent dosimeter (TLD), ion chamber (IC) and 2D Array detector systems. The difference between the dose values obtained from the dosimetric systems and treatment planning system (TPS) were found to be about % 5. For the measured (TLD) and calculated (TPS) doses %3 percentage differences were obtained for the points close to center while percentage differences increased at the field edges. It was found that TLD and IC measurements will increase the precision and reliability of the results of 2D Array.

  13. On the implementation of a recently proposed dosimetric formalism to a robotic radiosurgery system

    SciTech Connect

    Pantelis, E.; Moutsatsos, A.; Zourari, K.; Kilby, W.; Antypas, C.; Papagiannis, P.; Karaiskos, P.; Georgiou, E.; Sakelliou, L.

    2010-05-15

    Purpose: The aim of this work is to implement a recently proposed dosimetric formalism for nonstandard fields to the calibration and small field output factor measurement of a robotic stereotactic radiosurgery system. Methods: Reference dosimetry measurements were performed in the nonstandard, 60 mm diameter machine specific reference (msr) field using a Farmer ion chamber, five other cylindrical chambers with cavity lengths ranging from 16.25 down to 2.7 mm, and alanine dosimeters. Output factor measurements were performed for the 5, 7.5, 10, and 15 mm field sizes using microchambers, diode detectors, alanine dosimeters, TLD microcubes, and EBT Gafchromic films. Measurement correction factors as described in the proposed formalism were calculated for the ion chamber and diode detector output factor measurements based on published Monte Carlo data. Corresponding volume averaging correction factors were calculated for the alanine output factor measurements using 3D dose distributions, measured with polymer gel dosimeters. Results: Farmer chamber and alanine reference dosimetry results were found in close agreement, yielding a correction factor of k{sub Q{sub m{sub s{sub r,Q}{sup f{sub m}{sub s}{sub r},f{sub r}{sub e}{sub f}}}}}=0.999{+-}0.016 for the chamber readings. These results were also found to be in agreement within experimental uncertainties with corresponding results obtained using the shorter cavity length ionization chambers. The mean measured dose values of the latter, however, were found to be consistently greater than that of the Farmer chamber. This finding, combined with an observed inverse relationship between the mean measured dose and chamber cavity length that follows the trend predicted by theoretical volume averaging calculations in the msr field, implies that the Farmer k{sub Q{sub m{sub s{sub r,Q}{sup f{sub m}{sub s}{sub r},f{sub r}{sub e}{sub f}}}}} correction is greater than unity. Regarding the output factor results, deviations as large as

  14. 39 CFR 762.15 - Postal Service payments not made by disbursement postal money order.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... postal money order, and may be made by electronic funds transfer. ... postal money order. 762.15 Section 762.15 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS General, Definitions,...

  15. 39 CFR 762.26 - Postal facilities not to cash disbursement postal money orders.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... money orders. 762.26 Section 762.26 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.26 Postal facilities not...

  16. 39 CFR 762.26 - Postal facilities not to cash disbursement postal money orders.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... money orders. 762.26 Section 762.26 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.26 Postal facilities not...

  17. Dosimetric evaluation of two treatment planning systems for high dose rate brachytherapy applications.

    PubMed

    Shwetha, Bondel; Ravikumar, Manickam; Supe, Sanjay S; Sathiyan, Saminathan; Lokesh, Vishwanath; Keshava, Subbarao L

    2012-01-01

    Various treatment planning systems are used to design plans for the treatment of cervical cancer using high-dose-rate brachytherapy. The purpose of this study was to make a dosimetric comparison of the 2 treatment planning systems from Varian medical systems, namely ABACUS and BrachyVision. The dose distribution of Ir-192 source generated with a single dwell position was compared using ABACUS (version 3.1) and BrachyVision (version 6.5) planning systems. Ten patients with intracavitary applications were planned on both systems using orthogonal radiographs. Doses were calculated at the prescription points (point A, right and left) and reference points RU, LU, RM, LM, bladder, and rectum. For single dwell position, little difference was observed in the doses to points along the perpendicular bisector. The mean difference between ABACUS and BrachyVision for these points was 1.88%. The mean difference in the dose calculated toward the distal end of the cable by ABACUS and BrachyVision was 3.78%, whereas along the proximal end the difference was 19.82%. For the patient case there was approximately 2% difference between ABACUS and BrachyVision planning for dose to the prescription points. The dose difference for the reference points ranged from 0.4-1.5%. For bladder and rectum, the differences were 5.2% and 13.5%, respectively. The dose difference between the rectum points was statistically significant. There is considerable difference between the dose calculations performed by the 2 treatment planning systems. It is seen that these discrepancies are caused by the differences in the calculation methodology adopted by the 2 systems.

  18. Postal cancellation from spaceport

    NASA Astrophysics Data System (ADS)

    The John F. Kennedy Space Center, in cooperation with the United States Postal Service, is offering a cancellation service to interested philatelists for the space flight programs at Kennedy.Philatelists who wish to avail themselves of this service may do so by following the procedures outlined below: Specify the event for which you wish this service. There is a limit of five covers per customer per event.

  19. Design and dosimetric characteristics of a new endocavitary contact radiotherapy system using an electronic brachytherapy source

    SciTech Connect

    Richardson, Susan; Garcia-Ramirez, Jose; Lu Wei; Myerson, Robert J.; Parikh, Parag

    2012-11-15

    Purpose: To present design aspects and acceptance tests performed for clinical implementation of electronic brachytherapy treatment of early stage rectal adenocarcinoma. A dosimetric comparison is made between the historically used Philips RT-50 unit and the newly developed Axxent{sup Registered-Sign} Model S700 electronic brachytherapy source manufactured by Xoft (iCad, Inc.). Methods: Two proctoscope cones were manufactured by ElectroSurgical Instruments (ESI). Two custom surface applicators were manufactured by Xoft and were designed to fit and interlock with the proctoscope cones from ESI. Dose rates, half value layers (HVL), and percentage depth dose (PDD) measurements were made with the Xoft system and compared to historical RT-50 data. A description of the patient treatment approach and exposure rates during the procedure is also provided. Results: The electronic brachytherapy system has a lower surface dose rate than the RT-50. The dose rate to water on the surface from the Xoft system is approximately 2.1 Gy/min while the RT-50 is 10-12 Gy/min. However, treatment times with Xoft are still reasonable. The HVLs and PDDs between the two systems were comparable resulting in similar doses to the target and to regions beyond the target. The exposure rate levels around a patient treatment were acceptable. The standard uncertainty in the dose rate to water on the surface is approximately {+-}5.2%. Conclusions: The Philips RT-50 unit is an out-of-date radiotherapy machine that is no longer manufactured with limited replacement parts. The use of a custom-designed proctoscope and Xoft surface applicators allows delivery of a well-established treatment with the ease of a modern radiotherapy device. While the dose rate is lower with the use of Xoft, the treatment times are still reasonable. Additionally, personnel may stand farther away from the Xoft radiation source, thus potentially reducing radiation exposure to the operator and other personnel.

  20. A new fully integrated X-ray irradiator system for dosimetric research.

    PubMed

    Richter, D; Mittelstraß, D; Kreutzer, S; Pintaske, R; Dornich, K; Fuchs, M

    2016-06-01

    A fully housed X-ray irradiator was developed for use within lexsyg or Magnettech desktop equipment. The importance of hardening of the low energy photon radiation is discussed, its performance and feasibility is empirically shown and sustained by basic numerical simulations. Results of the latter for various materials are given for different X-ray source settings in order to provide estimates on the required setup for the irradiation of different geometries and materials. A Si-photodiode provides real-time monitoring of the X-ray-irradiator designed for use in dosimetric dating and other dosimetric application where irradiation of small samples or dosemeters is required. PMID:27041090

  1. Evaluation of the dosimetric accuracy for a couch-based tracking system (CBTS)

    NASA Astrophysics Data System (ADS)

    Chang, Kyung Hwan; Lee, Suk; Kim, Kwang Hyeon; Shim, Jang Bo; Yang, Dae Sik; Park, Young Je; Yoon, Won Sup; Kim, Chul Yong; Cao, Yuanjie

    2016-07-01

    In this study, the geometric and dosimetric accuracy of an in-house-developed couch-based tracking system (CBTS) was investigated using both film and in-house-developed polymer gel dosimeters. We evaluated the 1D and the 2D motion accuracies of our couch system by using Gafchromic EBT film. For the 1D test, the couch system was moved 5, 10, and 20 mm in the X, Y, and Z directions, respectively. Meanwhile, for the 2D test, it was moved along the XY, YZ, and ZX directions. We compared the profiles, full widths at half maximum (FWHMs), and penumbras between the static and the tracking fields. For the 3D test, we quantitatively compared the dose distribution between the static and the tracking fields by using the polymer gel dosimeter when it was simultaneously moved in the XYZ directions. We confirmed that the film was moved according to motion amplitudes of 5, 10, and 20 mm in the X, Y, and Z directions, respectively, in the 1D and 2D motion tests. The value of the FWHM of the static field and the three tracking fields were 51.88, 53.28, 57.67, and 64.43 mm, respectively. Two types of penumbras became wider with increasing amplitudes compared to the static field. For the 3D test, the dose distribution of the XYZ tracking field was qualitatively larger than that of the static field. We conclude that this CBTS has the potential for pre-clinical applications in adaptive radiation therapy.

  2. Dosimetric quality control of Eclipse treatment planning system using pelvic digital test object

    NASA Astrophysics Data System (ADS)

    Benhdech, Yassine; Beaumont, Stéphane; Guédon, Jeanpierre; Crespin, Sylvain

    2011-03-01

    Last year, we demonstrated the feasibility of a new method to perform dosimetric quality control of Treatment Planning Systems in radiotherapy, this method is based on Monte-Carlo simulations and uses anatomical Digital Test Objects (DTOs). The pelvic DTO was used in order to assess this new method on an ECLIPSE VARIAN Treatment Planning System. Large dose variations were observed particularly in air and bone equivalent material. In this current work, we discuss the results of the previous paper and provide an explanation for observed dose differences, the VARIAN Eclipse (Anisotropic Analytical) algorithm was investigated. Monte Carlo simulations (MC) were performed with a PENELOPE code version 2003. To increase efficiency of MC simulations, we have used our parallelized version based on the standard MPI (Message Passing Interface). The parallel code has been run on a 32- processor SGI cluster. The study was carried out using pelvic DTOs and was performed for low- and high-energy photon beams (6 and 18MV) on 2100CD VARIAN linear accelerator. A square field (10x10 cm2) was used. Assuming the MC data as reference, χ index analyze was carried out. For this study, a distance to agreement (DTA) was set to 7mm while the dose difference was set to 5% as recommended in the TRS-430 and TG-53 (on the beam axis in 3-D inhomogeneities). When using Monte Carlo PENELOPE, the absorbed dose is computed to the medium, however the TPS computes dose to water. We have used the method described by Siebers et al. based on Bragg-Gray cavity theory to convert MC simulated dose to medium to dose to water. Results show a strong consistency between ECLIPSE and MC calculations on the beam axis.

  3. 78 FR 69711 - Change in Postal Rates

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ... Change in Postal Rates AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently Postal Service filing concerning the Postal Service's intention to change rates of..., the Postal Service filed notice with the Commission concerning changes in rates of...

  4. 76 FR 47275 - Postal Service Initiative on Retail Postal Locations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ..., the facility must remain open for a further 60 days. Id. at 10. The Postal Service states that it... oral cross-examination. September 8, 2011 Hearing on the Postal service's direct case (9:30 AM in the...). October 3, 2011 Hearing to enter rebuttal testimony into the record (9:30 AM in the commission's...

  5. 77 FR 2676 - Competitive Postal Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-19

    ... Postal Service an artificial competitive advantage. The Commission gave considerable weight to the... 39 CFR Part 3015 Competitive Postal Products AGENCY: Postal Regulatory Commission. ACTION: Notice of proposed rulemaking. SUMMARY: The Commission is initiating a review to determine whether...

  6. 75 FR 70754 - Postal Classification Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-18

    ... Postal Classification Changes AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request announcing a classification change affecting... Notice with the Commission announcing a classification change ] established by the Governors.\\1\\...

  7. 78 FR 37246 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-20

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice SUMMARY: The Commission is... the introductory (``Whereas'') paragraphs of the Agreement; revisions to existing articles; and...

  8. 78 FR 79710 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-31

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... introductory paragraphs of the Agreement; revisions to numerous existing articles; and new, deleted,...

  9. Dosimetric characterization of radionuclides for systemic tumor therapy: Influence of particle range, photon emission, and subcellular distribution

    SciTech Connect

    Uusijaervi, Helena; Bernhardt, Peter; Ericsson, Thomas; Forssell-Aronsson, Eva

    2006-09-15

    Various radionuclides have been proposed for systemic tumor therapy. However, in most dosimetric analysis of proposed radionuclides the charged particles are taken into consideration while the potential photons are ignored. The photons will cause undesirable irradiation of normal tissue, and increase the probability of toxicity in, e.g., the bone marrow. The aim of this study was to investigate the dosimetric properties according to particle range, photon emission, and subcellular radionuclide distribution, of a selection of radionuclides used or proposed for radionuclide therapy, and to investigate the possibility of dividing radionuclides into groups according to their dosimetric properties. The absorbed dose rate to the tumors divided by the absorbed dose rate to the normal tissue (TND) was estimated for different tumor sizes in a mathematical model of the human body. The body was simulated as a 70-kg ellipsoid and the tumors as spheres of different sizes (1 ng-100 g). The radionuclides were either assumed to be uniformly distributed throughout the entire tumor and normal tissue, or located in the nucleus or the cytoplasm of the tumor cells and on the cell membrane of the normal cells. Fifty-nine radionuclides were studied together with monoenergetic electrons, positrons, and alpha particles. The tumor and normal tissue were assumed to be of water density. The activity concentration ratio between the tumor and normal tissue was assumed to be 25. The radionuclides emitting low-energy electrons combined with a low photon contribution, and the alpha emitters showed high TND values for most tumor sizes. Electrons with higher energy gave reduced TND values for small tumors, while a higher photon contribution reduced the TND values for large tumors. Radionuclides with high photon contributions showed low TND value for all tumor sizes studied. The radionuclides studied could be divided into four main groups according to their TND values: beta emitters, Auger electron

  10. Commissioning and dosimetric characteristics of TrueBeam system: Composite data of three TrueBeam machines

    SciTech Connect

    Chang Zheng; Wu Qiuwen; Adamson, Justus; Ren Lei; Bowsher, James; Yan Hui; Thomas, Andrew; Yin Fangfang

    2012-11-15

    Purpose: A TrueBeam linear accelerator (TB-LINAC) is designed to deliver traditionally flattened and flattening-filter-free (FFF) beams. Although it has been widely adopted in many clinics for patient treatment, limited information is available related to commissioning of this type of machine. In this work, commissioning data of three units were measured, and multiunit comparison was presented to provide valuable insights and reliable evaluations on the characteristics of the new treatment system. Methods: The TB-LINAC is equipped with newly designed waveguide, carousel assembly, monitoring control, and integrated imaging systems. Each machine in this study has 4, 6, 8, 10, 15 MV flattened photon beams, and 6 MV and 10 MV FFF photon beams as well as 6, 9, 12, 16, 20, and 22 MeV electron beams. Dosimetric characteristics of the three new TB-LINAC treatment units are systematically measured for commissioning. High-resolution diode detectors and ion chambers were used to measure dosimetric data for a range of field sizes from 10 Multiplication-Sign 10 to 400 Multiplication-Sign 400 mm{sup 2}. The composite dosimetric data of the three units are presented in this work. The commissioning of intensity modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), image-guided radiation therapy, and gating systems are also illustrated. Critical considerations of P{sub ion} of FFF photon beams and small field dosimetric measurements were investigated. Results: The authors found all PDDs and profiles matched well among the three machines. Beam data were quantitatively compared and combined through average to yield composite beam data. The discrepancies among the machines were quantified using standard deviation (SD). The mean SD of the PDDs among the three units is 0.12%, and the mean SD of the profiles is 0.40% for 10 MV FFF open fields. The variations of P{sub ion} of the chamber CC13 is 1.2 {+-} 0.1% under 6 MV FFF and 2.0 {+-} 0.5% under 10 MV FFF from dmax to

  11. 75 FR 65386 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to add another Global Expedited Package Services 3...

  12. 75 FR 40853 - Postal Rate Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-14

    ... Postal Rate Changes AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: Under a 2006 postal reform law, a new approach to implementing rate changes for market dominant postal products, which... based on changes in a specified Consumer Price Index (CPI). However, the law includes a...

  13. 76 FR 47615 - Postal Rate Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-05

    ... Postal Rate Changes AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to change rates for Inbound International Expedited... Paragraphs I. Introduction On July 28, 2011, the Postal Service filed a notice announcing changes in...

  14. 75 FR 51504 - Changes in Postal Rates

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-20

    ... Changes in Postal Rates AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service filing to change rates for Inbound International Expedited..., 2010, the Postal Service filed a notice announcing changes in rates not of general applicability...

  15. 76 FR 13242 - Change in Postal Prices

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-10

    ... Change in Postal Prices AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request for a change in prices to Parcel Select Contract 1. This..., 2011, the Postal Service filed notice of a change in prices to Parcel Select Contract 1, which...

  16. 77 FR 36585 - Postal Rate Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-19

    ... Postal Rate Changes AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service notice of rate and changes affecting Inbound Air Parcel Post at... 11, 2012, the Postal Service filed a notice, in accordance with 39 CFR 3015.5, announcing changes...

  17. 78 FR 52223 - Change in Postal Rates

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-22

    ... Change in Postal Rates AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently Postal Service filing concerning the Postal Service's intention to change rates for... 3015.5, announcing its intention to change rates for Inbound International Expedited Services...

  18. 77 FR 42341 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-18

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to add Every Door Direct Mail-Retail (EDDM-R) to...

  19. 75 FR 26812 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-12

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to add a Global Direct Contracts 1 (MC2010-17)...

  20. 77 FR 50729 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-22

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request for two related changes to the product lists. The...

  1. 75 FR 44029 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-27

    ... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... the new contract to begin August 1, 2010. In support of its Notice, the Postal Service filed five... Postal Service also contends that its filings demonstrate that the new GEPS 3 contract complies with...

  2. 75 FR 22633 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-29

    ... From the Federal Register Online via the Government Publishing Office ] POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission.... The Postal Service contends that its filings demonstrate that each of the new GEPS 2 contracts...

  3. 75 FR 17175 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is.... The Postal Service contends that its filings demonstrate that each of the new GEPS 2 contracts...

  4. 76 FR 67496 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-01

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to enter into an additional Inbound Competitive...

  5. 75 FR 28076 - New Postal Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-19

    ... New Postal Products AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to add new Global Expedited Package Services 2 products to.... The Postal Service contends that its filings demonstrate that each of the new GEPS 2...

  6. 76 FR 593 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-05

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to add a Global Expedited Package Services 3 contract...

  7. 75 FR 67148 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-01

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is.... at 4. The Postal Service concludes that its filings demonstrate that each of the new GEPS 3...

  8. 78 FR 77172 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-20

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning a contract with Canada for the delivery of...

  9. 78 FR 76334 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-17

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing requesting an amendment to Parcel Select Contract 6. This...

  10. 76 FR 394 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-04

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to add a Global Direct Contracts 1 contract to...

  11. 77 FR 58185 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-19

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to add a Global Expedited Package Services contract to...

  12. 76 FR 49798 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-11

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is.... CP2010-36.'' Id. The Postal Service concludes that its filing demonstrates that the new GREP...

  13. 75 FR 67146 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-01

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... 4. The Postal Service concludes that its filings demonstrate that each of the new GEPS 3...

  14. 78 FR 76333 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-17

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing requesting an amendment to Priority Mail Contract 29. This...

  15. 78 FR 42566 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-16

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is...; and new, deleted, and renumbered articles. Id. at 3-7. The Postal Service states that...

  16. 76 FR 80412 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-23

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION Docket No. CP2012-4; Order No. 1057] New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to enter into...

  17. 78 FR 8597 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning the addition of Priority Mail Contract 53 to...

  18. 78 FR 4173 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-18

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning the addition of Express Mail Contract 13 to...

  19. 77 FR 76571 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning the addition of Priority Mail Contract 49 to...

  20. 78 FR 6358 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-30

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning the addition of Priority Mail Contract 52 to...

  1. 77 FR 66192 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-02

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning the addition of Parcel Select Contract 6 to...

  2. 77 FR 76570 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning the addition of Priority Mail Contract 50 to...

  3. 78 FR 8598 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recent Postal Service filing concerning the addition of Priority Mail Contract 54 to...

  4. Dosimetric accuracy of the cone-beam CT-based treatment planning of the Vero system: a phantom study.

    PubMed

    Yohannes, Indra; Prasetio, Heru; Kallis, Karoline; Bert, Christoph

    2016-01-01

    We report an investigation on the accuracy of dose calculation based on the cone-beam computed tomography (CBCT) images of the nonbowtie filter kV imaging system of the Vero linear accelerator. Different sets of materials and tube voltages were employed to generate the Hounsfield unit lookup tables (HLUTs) for both CBCT and fan-beam CT (FBCT) systems. The HLUTs were then implemented for the dose calculation in a treatment planning system (TPS). Dosimetric evaluation was carried out on an in-house-developed cube phantom that consists of water-equivalent slabs and inhomogeneity inserts. Two independent dosimeters positioned in the cube phantom were used in this study for point-dose and two-dimensional (2D) dose distribution measurements. The differences of HLUTs from various materials and tube voltages in both CT systems resulted in differences in dose calculation accuracy. We found that the higher the tube voltage used to obtain CT images, the better the point-dose calculation and the gamma passing rate of the 2D dose distribution agree to the values determined in the TPS. Moreover, the insert materials that are not tissue-equivalent led to higher dose-calculation inaccuracy. There were negligible differences in dosimetric evaluation between the CBCT- and FBCT-based treatment planning if the HLUTs were generated using the tissue-equivalent materials. In this study, the CBCT images of the Vero system from a complex inhomogeneity phantom can be applied for the TPS dose calculation if the system is calibrated using tissue-equivalent materials scanned at high tube voltage (i.e., 120 kV). PMID:27455496

  5. New method to perform dosimetric quality control of treatment planning system using PENELOPE Monte Carlo and anatomical digital test objects

    NASA Astrophysics Data System (ADS)

    Benhdech, Yassine; Beaumont, Stéphane; Guédon, Jean-Pierre; Torfeh, Tarraf

    2010-04-01

    In this paper, we deepen the R&D program named DTO-DC (Digital Object Test and Dosimetric Console), which goal is to develop an efficient, accurate and full method to achieve dosimetric quality control (QC) of radiotherapy treatment planning system (TPS). This method is mainly based on Digital Test Objects (DTOs) and on Monte Carlo (MC) simulation using the PENELOPE code [1]. These benchmark simulations can advantageously replace experimental measures typically used as reference for comparison with TPS calculated dose. Indeed, the MC simulations rather than dosimetric measurements allow contemplating QC without tying treatment devices and offer in many situations (i.p. heterogeneous medium, lack of scattering volume...) better accuracy compared to dose measurements with classical dosimetry equipment of a radiation therapy department. Furthermore using MC simulations and DTOs, i.e. a totally numerical QC tools, will also simplify QC implementation, and enable process automation; this allows radiotherapy centers to have a more complete and thorough QC. The program DTO-DC was established primarily on ELEKTA accelerator (photons mode) using non-anatomical DTOs [2]. Today our aim is to complete and apply this program on VARIAN accelerator (photons and electrons mode) using anatomical DTOs. First, we developed, modeled and created three anatomical DTOs in DICOM format: 'Head and Neck', Thorax and Pelvis. We parallelized the PENELOPE code using MPI libraries to accelerate their calculation, we have modeled in PENELOPE geometry Clinac head of Varian Clinac 2100CD (photons mode). Then, to implement this method, we calculated the dose distributions in Pelvis DTO using PENELOPE and ECLIPSE TPS. Finally we compared simulated and calculated dose distributions employing the relative difference proposed by Venselaar [3]. The results of this work demonstrate the feasibility of this method that provides a more accurate and easily achievable QC. Nonetheless, this method, implemented

  6. Potential application of metal nanoparticles for dosimetric systems: Concepts and perspectives

    SciTech Connect

    Guidelli, Eder José Baffa, Oswaldo

    2014-11-07

    Metallic nanoparticles increase the delivered dose and consequently enhance tissue radio sensitization during radiation therapy of cancer. The Dose Enhancement Factor (DEF) corresponds to the ratio between the dose deposited on a tissue containing nanoparticles, and the dose deposited on a tissue without nanoparticles. In this sense, we have used electron spin resonance spectroscopy (ESR) to investigate how silver and gold nanoparticles affect the dose deposition in alanine dosimeters, which act as a surrogate of soft tissue. Besides optimizing radiation absorption by the dosimeter, the optical properties of these metal nanoparticles could also improve light emission from materials employed as radiation detectors. Therefore, we have also examined how the plasmonic properties of noble metal nanoparticles could enhance radiation detection using optically stimulated luminescence (OSL) dosimetry. This work will show results on how the use of gold and silver nanoparticles are beneficial for the ESR and OSL dosimetric techniques, and will describe the difficulties we have been facing, the challenges to overcome, and the perspectives.

  7. Potential application of metal nanoparticles for dosimetric systems: Concepts and perspectives

    NASA Astrophysics Data System (ADS)

    Guidelli, Eder José; Baffa, Oswaldo

    2014-11-01

    Metallic nanoparticles increase the delivered dose and consequently enhance tissue radio sensitization during radiation therapy of cancer. The Dose Enhancement Factor (DEF) corresponds to the ratio between the dose deposited on a tissue containing nanoparticles, and the dose deposited on a tissue without nanoparticles. In this sense, we have used electron spin resonance spectroscopy (ESR) to investigate how silver and gold nanoparticles affect the dose deposition in alanine dosimeters, which act as a surrogate of soft tissue. Besides optimizing radiation absorption by the dosimeter, the optical properties of these metal nanoparticles could also improve light emission from materials employed as radiation detectors. Therefore, we have also examined how the plasmonic properties of noble metal nanoparticles could enhance radiation detection using optically stimulated luminescence (OSL) dosimetry. This work will show results on how the use of gold and silver nanoparticles are beneficial for the ESR and OSL dosimetric techniques, and will describe the difficulties we have been facing, the challenges to overcome, and the perspectives.

  8. Preliminary evaluation of the dosimetric accuracy of the in vivo plastic scintillation detector OARtrac system for prostate cancer treatments

    PubMed Central

    Klawikowski, Slade J.; Zeringue, Clint; Wootton, Landon S.; Ibbott, Geoffrey S.; Beddar, Sam

    2014-01-01

    A promising, new, in vivo prostate dosimetry system has been developed for clinical radiation therapy. This work outlines the preliminary end-to-end testing of the accuracy and precision of the new OARtrac scintillation dosimetry system. We tested 94 calibrated plastic scintillation detector (PSD) probes before their final integration into endorectal balloon assemblies. These probes had been calibrated at The University of Texas MD Anderson Cancer Center Dosimetry Laboratory (MDADL). We used a complete clinical OARtrac system including the PSD probes, charge coupled device (CCD camera) monitoring system, and the manufacturer’s integrated software package. The PSD probes were irradiated at 6 MV in a Solid Water® phantom. Irradiations were performed with a 6 MV linear accelerator using anterior-posterior/posterior-anterior (AP/PA) matched fields to a maximum dose of 200 cGy in a 100 cm source-axis distance (SAD geometry. As a whole, the OARtrac system has good accuracy with a mean error of 0.01% and an error spread of ± 5.4% at the 95% confidence interval. These results reflect the PSD probes’ accuracy before their final insertion into endorectal balloons. Future work will test the dosimetric effects of mounting the PSD probes within the endorectal balloon assemblies. PMID:24732073

  9. 76 FR 55619 - Performance Measurement for Special Postal Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-08

    ... 39 CFR Part 3055 Performance Measurement for Special Postal Services AGENCY: Postal Regulatory... requirements for the measurement of the level of service the Postal Service provides in connection with Stamp... recent Postal Service representations about proposed service standards, measurement methods,...

  10. 77 FR 54937 - International Mail Postal Contract

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-06

    ... (2) asks the Commission to include the new contract within the International Business Reply Service... Functionally Equivalent International Business Reply Service Competitive Contract 3 Negotiated Settlement... COMMISSION International Mail Postal Contract AGENCY: Postal Regulatory Commission. ACTION: Notice....

  11. 76 FR 11823 - New Postal Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-03

    ... New Postal Products AGENCY: Postal Regulatory Commission. ACTION: Notice. ] SUMMARY: This notice... and adding a new product to the competitive product list. This notice identifies preliminary... a new product, provisionally titled Lightweight Commercial Parcels, to the competitive product...

  12. 75 FR 61785 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-06

    ...; Order No. 548] New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The... that each of the new GEPS 3 contracts complies with the requirements of 39 U.S.C. 3633 and...

  13. 75 FR 53353 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... noticing a recently-filed Postal Service request to add Inbound Competitive Multi-Service Agreements with...., to add Inbound Competitive Multi-Service Agreements with Foreign Postal Operators (Multi-Service Agreements) to the competitive product list.\\1\\ The Postal Service asserts that Multi-Service Agreements...

  14. 76 FR 7883 - Postal Service Rate Adjustment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... rate adjustment.\\1\\ The Notice concerns the inbound portion of a bilateral agreement with HongKong Post... upon the Postal Service obtaining all regulatory approvals and notifying HongKong Post that all such... Agreement (CPG) Agreement. The Postal Service and HongKong Post, the postal operator for Hong Kong,...

  15. 76 FR 22739 - Postal Service Market Test

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-22

    ... Postal Service Market Test AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service proposal to conduct a limited market test involving a... describes the proposed test, addresses procedural aspects of the filing, and invites public comment....

  16. 76 FR 25381 - Postal Service Market Test

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-04

    ... Postal Service Market Test AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission... Logistics experimental market test, pending Commission action on anticipated request for permanent status... Postal Service moved to temporarily extend its Collaborative Logistics market test under 39 U.S.C....

  17. 32 CFR 700.812 - Postal matters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 5 2011-07-01 2011-07-01 false Postal matters. 700.812 Section 700.812 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY UNITED STATES NAVY REGULATIONS AND... Officers in General § 700.812 Postal matters. Commanding officers shall ensure that mail and postal...

  18. 32 CFR 700.812 - Postal matters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 5 2014-07-01 2014-07-01 false Postal matters. 700.812 Section 700.812 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY UNITED STATES NAVY REGULATIONS AND... Officers in General § 700.812 Postal matters. Commanding officers shall ensure that mail and postal...

  19. 32 CFR 700.812 - Postal matters.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Postal matters. 700.812 Section 700.812 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY UNITED STATES NAVY REGULATIONS AND... Officers in General § 700.812 Postal matters. Commanding officers shall ensure that mail and postal...

  20. 32 CFR 700.812 - Postal matters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 5 2013-07-01 2013-07-01 false Postal matters. 700.812 Section 700.812 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY UNITED STATES NAVY REGULATIONS AND... Officers in General § 700.812 Postal matters. Commanding officers shall ensure that mail and postal...

  1. 32 CFR 700.812 - Postal matters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Postal matters. 700.812 Section 700.812 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY UNITED STATES NAVY REGULATIONS AND... Officers in General § 700.812 Postal matters. Commanding officers shall ensure that mail and postal...

  2. 75 FR 39710 - Postal Classification Change

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-12

    ... Postal Classification Change AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request concerning two classification changes to... filed a notice pursuant to 39 CFR 3020.90 and 3020.91 concerning two classification changes to...

  3. 75 FR 69145 - Postal Rate Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-10

    ... Postal Rate Changes AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to change rates for Inbound Air Parcel Post at Universal... Service filed a notice announcing changes in rates not of general applicability for Inbound Air...

  4. 75 FR 166 - Postal Product Price Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-04

    ... Postal Product Price Changes AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to change prices for a Global Plus 2 contract... contract at issue in the above-captioned proceeding will change as contemplated by the contract's...

  5. 75 FR 57087 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... that this new GEPS 3 contract complies with the requirements of 39 U.S.C. 3633 and is...

  6. 75 FR 67147 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-01

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... demonstrate that the new GREP contract complies with the requirements of 39 U.S.C. 3633 and is...

  7. 78 FR 77508 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-23

    ... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is.... 09-15; Attachment 3--a redacted copy of the new rates; and Attachment 4--a copy of the certification... referenced Governors' Decision, the new rates and related financial information. Id. at 3. The Postal...

  8. 77 FR 27491 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-10

    ... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... profitable new mail; will enhance the financial position of the Postal Service; will increase mail volume... Mail. Id. at 4. To be eligible for the contract prices, Valassis must initiate new shared...

  9. 75 FR 44292 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-28

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... contract related to the proposed new product pursuant to 39 U.S.C. 3632(b)(3) and 39 CFR 3015.5....

  10. 75 FR 57303 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-20

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... demonstrate that each of the new GEPS 3 contracts complies with the requirements of 39 U.S.C. 3633 and...

  11. 78 FR 65014 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-30

    ... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... Postal Service contemporaneously filed a redacted contract related to the proposed new product under 39 U...: Attachment A--a redacted copy of Governors' Decision No. 11-6, authorizing the new product; Attachment...

  12. 75 FR 65676 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... demonstrate that each of the new GEPS 3 contracts complies with the requirements of 39 U.S.C. 3633 and...

  13. 78 FR 47431 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-05

    ... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is.... Ordering Paragraphs I. Introduction On July 26, 2013, the Postal Service filed a request to create a new... Mailer from the market dominant product list; and (2) add the new Round-Trip Mailer product to...

  14. 75 FR 44138 - New Postal Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-28

    ..., 2010 (75 FR 12445), the following additions to the competitive product list have been made: Reseller... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION 30 CFR Part 3020 New Postal Products AGENCY: Postal Regulatory Commission. ACTION: Final...

  15. 75 FR 54401 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-07

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... that each of the new GEPS 3 contracts complies with the requirements of 39 U.S.C. 3633 and...

  16. 75 FR 65675 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... competitive product list. It is also noticing a contemporaneous Postal Service notice that new rates for... contemporaneously filed notice pursuant to 39 U.S.C. 3632(b)(3) and 39 CFR 3015.5 that new rates for inbound...

  17. 76 FR 592 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-05

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... that the new GREP contract complies with the requirements of 39 U.S.C. 3633 and is...

  18. 75 FR 3988 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-26

    ...: Regulatory History, 74 FR 62357 (November 27, 2009). ] I. Introduction II. Background III. Comments IV. Commission Analysis V. Ordering Paragraphs I. Introduction The Postal Service seeks to add a new product... 39 CFR Part 3020 New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Final rule....

  19. 75 FR 80858 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... Service contemporaneously filed a contract related to the proposed new product pursuant to 39 U.S.C....

  20. 78 FR 30940 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-23

    ... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is...). The Postal Service contemporaneously filed a redacted contract related to the proposed new product... follows: Attachment A--a redacted copy of Governors' Decision No. 11-6, authorizing the new...

  1. 75 FR 57995 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-23

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... Service concludes that its filings demonstrate that each of the new GEPS 3 contracts complies with...

  2. 78 FR 63519 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... redacted contract related to the proposed new product. Id. Attachment B. The instant contract has...

  3. 75 FR 51505 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-20

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... new product pursuant to 39 U.S.C. 3632(b)(3) and 39 CFR 3015.5. The contract has been assigned...

  4. 78 FR 35650 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-13

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... articles, and new annexes, but asserts that these differences do not detract from a finding of...

  5. 76 FR 395 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-04

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... contract related to the proposed new product. Request, Attachment B. The contract has been assigned...

  6. 75 FR 35102 - New Postal Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-21

    ... New Postal Products AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to add new Global Expedited Package Services 2 products to... Service also contends that its filing demonstrates that each of the new GEPS 2 contracts complies with...

  7. 75 FR 65532 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-25

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... new product pursuant to 39 U.S.C. 3632(b)(3) and 39 CFR 3015.5. The contract has been assigned...

  8. 75 FR 9005 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ..., 74 FR 49823 (Sept. 29, 2009). Table of Contents I. Introduction II. Notice of Filing III. Ordering... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... incidental differences. Id. at 6. The Postal Service contends that its filings demonstrate that this new...

  9. 75 FR 14475 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... contends that its filings demonstrate that each of the new GEPS 2 contracts comply with the requirements...

  10. 75 FR 8758 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-25

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... contends that its filings demonstrate that this new GEPS 2 contract is established in compliance with...

  11. 75 FR 3383 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-21

    ...-6820 or stephen.sharfman@prc.gov . SUPPLEMENTARY INFORMATION: Regulatory History, 74 FR 57538 (November... 39 CFR Part 3020 New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Final rule. SUMMARY... Paragraphs I. Introduction The Postal Service seeks to add a new product identified as Express...

  12. 75 FR 53216 - New Postal Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... (75 FR 44138), the following additions to the competitive product list have been made: 1. Stamp... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION 39 CFR Part 3020 New Postal Products AGENCY: Postal Regulatory Commission. ACTION: Final...

  13. 75 FR 66677 - New Postal Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-29

    .... Changes. Since publication of the product lists in the Federal Register on August 31, 2010 (75 FR 53216... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION 39 CFR Part 3020 New Postal Products AGENCY: Postal Regulatory Commission. ACTION: Final...

  14. 75 FR 65531 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-25

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... new product pursuant to 39 U.S.C. 3632(b)(3) and 39 CFR 3015.5. The contract has been assigned...

  15. 75 FR 6108 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-08

    ....sharfman@prc.gov . SUPPLEMENTARY INFORMATION: Regulatory History, 74 FR 65169 (December 9, 2009). Table of...: The Commission is adding Canada Post-United States Postal Service Contractual Bilateral Agreement for.... Introduction The Postal Service seeks to add a new product, Canada Post-United States Postal...

  16. 39 CFR 501.13 - False representations of Postal Service actions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... MANUFACTURE AND DISTRIBUTE POSTAGE EVIDENCING SYSTEMS § 501.13 False representations of Postal Service actions... Evidencing Systems. The Postal Service reserves the right to suspend and/or revoke the authorization to manufacture or distribute Postage Evidencing Systems throughout the United States or any part thereof...

  17. 39 CFR 221.1 - The United States Postal Service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false The United States Postal Service. 221.1 Section 221.1 Postal Service UNITED STATES POSTAL SERVICE ORGANIZATION AND ADMINISTRATION GENERAL ORGANIZATION § 221.1 The United States Postal Service. The United States Postal Service was established as...

  18. 39 CFR 221.1 - The United States Postal Service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false The United States Postal Service. 221.1 Section 221.1 Postal Service UNITED STATES POSTAL SERVICE ORGANIZATION AND ADMINISTRATION GENERAL ORGANIZATION § 221.1 The United States Postal Service. The United States Postal Service was established as...

  19. 39 CFR 221.1 - The United States Postal Service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false The United States Postal Service. 221.1 Section 221.1 Postal Service UNITED STATES POSTAL SERVICE ORGANIZATION AND ADMINISTRATION GENERAL ORGANIZATION § 221.1 The United States Postal Service. The United States Postal Service was established as...

  20. Dosimetric evaluation of PLATO and Oncentra treatment planning systems for High Dose Rate (HDR) brachytherapy gynecological treatments

    SciTech Connect

    Singh, Hardev; De La Fuente Herman, Tania; Showalter, Barry; Thompson, Spencer J.; Syzek, Elizabeth J.; Herman, Terence; Ahmad, Salahuddin

    2012-10-23

    This study compares the dosimetric differences in HDR brachytherapy treatment plans calculated with Nucletron's PLATO and Oncentra MasterPlan treatment planning systems (TPS). Ten patients (1 T1b, 1 T2a, 6 T2b, 2 T4) having cervical carcinoma, median age of 43.5 years (range, 34-79 years) treated with tandem and ring applicator in our institution were selected retrospectively for this study. For both Plato and Oncentra TPS, the same orthogonal films anterior-posterior (AP) and lateral were used to manually draw the prescription and anatomical points using definitions from the Manchester system and recommendations from the ICRU report 38. Data input for PLATO was done using a digitizer and Epson Expression 10000XL scanner was used for Oncentra where the points were selected on the images in the screen. The prescription doses for these patients were 30 Gy to points right A (RA) and left A (LA) delivered in 5 fractions with Ir-192 HDR source. Two arrangements: one dwell position and two dwell positions on the tandem were used for dose calculation. The doses to the patient points right B (RB) and left B (LB), and to the organs at risk (OAR), bladder and rectum for each patient were calculated. The mean dose and the mean percentage difference in dose calculated by the two treatment planning systems were compared. Paired t-tests were used for statistical analysis. No significant differences in mean RB, LB, bladder and rectum doses were found with p-values > 0.14. The mean percent difference of doses in RB, LB, bladder and rectum are found to be less than 2.2%, 1.8%, 1.3% and 2.2%, respectively. Dose calculations based on the two different treatment planning systems were found to be consistent and the treatment plans can be made with either system in our department without any concern.

  1. Determining the optimal dosimetric leaf gap setting for rounded leaf-end multileaf collimator systems by simple test fields.

    PubMed

    Yao, Weiguang; Farr, Jonathan B

    2015-01-01

    Individual QA for IMRT/VMAT plans is required by protocols. Sometimes plans cannot pass the institute's QA criteria. For the Eclipse treatment planning system (TPS) with rounded leaf-end multileaf collimator (MLC), one practical way to improve the agreement of planned and delivered doses is to tune the value of dosimetric leaf gap (DLG) in the TPS from the measured DLG. We propose that this step may be necessary due to the complexity of the MLC system, including dosimetry of small fields and the tongue-and-groove (T&G) effects, and report our use of test fields to obtain linac-specific optimal DLGs in TPSs. More than 20 original patient plans were reoptimized with the linac-specific optimal DLG value. We examined the distribution of gaps and T&G extensions in typical patient plans and the effect of using the optimal DLG on the distribution. The QA pass rate of patient plans using the optimal DLG was investigated. The dose-volume histograms (DVHs) of targets and organs at risk were checked. We tested three MLC systems (Varian millennium 120 MLC, high-definition 120 MLC, and Siemens 160 MLC) installed in four Varian linear accelerators (linacs) (TrueBEAM STx, Trilogy, Clinac 2300 iX, and Clinac 21 EX) and 1 Siemens linac (Artiste). With an optimal DLG, the individual QA for all those patient plans passed the institute's criteria (95% in DTA test or gamma test with 3%/3 mm/10%), even though most of these plans had failed to pass QA when using original DLGs optimized from typical patient plans or from the optimization process (automodeler) of Pinnacle TPS. Using either our optimal DLG or one optimized from typical patient plans or from the Pinnacle optimization process yielded similar DVHs. PMID:26218999

  2. Four-Dimensional Computed Tomography Based Respiratory-Gated Radiotherapy with Respiratory Guidance System: Analysis of Respiratory Signals and Dosimetric Comparison

    PubMed Central

    Kim, Chul Yong; Yang, Dae Sik; Yoon, Won Sup; Park, Young Je; Lee, Suk; Kim, Young Bum

    2014-01-01

    Purpose. To investigate the effectiveness of respiratory guidance system in 4-dimensional computed tomography (4DCT) based respiratory-gated radiation therapy (RGRT) by comparing respiratory signals and dosimetric analysis of treatment plans. Methods. The respiratory amplitude and period of the free, the audio device-guided, and the complex system-guided breathing were evaluated in eleven patients with lung or liver cancers. The dosimetric parameters were assessed by comparing free breathing CT plan and 4DCT-based 30–70% maximal intensity projection (MIP) plan. Results. The use of complex system-guided breathing showed significantly less variation in respiratory amplitude and period compared to the free or audio-guided breathing regarding the root mean square errors (RMSE) of full inspiration (P = 0.031), full expiration (P = 0.007), and period (P = 0.007). The dosimetric parameters including V5 Gy, V10 Gy, V20 Gy, V30 Gy, V40 Gy, and V50 Gy of normal liver or lung in 4DCT MIP plan were superior over free breathing CT plan. Conclusions. The reproducibility and regularity of respiratory amplitude and period were significantly improved with the complex system-guided breathing compared to the free or the audio-guided breathing. In addition, the treatment plan based on the 4D CT-based MIP images acquired with the complex system guided breathing showed better normal tissue sparing than that on the free breathing CT. PMID:25276775

  3. 39 CFR 255.8 - Access to postal facilities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Access to postal facilities. 255.8 Section 255.8 Postal Service UNITED STATES POSTAL SERVICE ORGANIZATION AND ADMINISTRATION ACCESS OF PERSONS WITH DISABILITIES TO POSTAL SERVICE PROGRAMS, ACTIVITIES, FACILITIES, AND ELECTRONIC AND INFORMATION...

  4. 39 CFR 3055.91 - Consumer access to postal services.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Consumer access to postal services. 3055.91 Section 3055.91 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Reporting of Customer Satisfaction § 3055.91 Consumer access to postal services. (a) The following information pertaining to...

  5. 39 CFR 3055.91 - Consumer access to postal services.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Consumer access to postal services. 3055.91 Section 3055.91 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Reporting of Customer Satisfaction § 3055.91 Consumer access to postal services. (a)...

  6. 39 CFR 255.7 - Special arrangements for postal services.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... offer other special arrangements to that individual. (a) The Postal Operations Manual offers information... particular postal services may contact their local postal manager. (d) Response to a request or complaint regarding a special arrangement for postal services. A local postal manager receiving a request or...

  7. 39 CFR 255.7 - Special arrangements for postal services.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... offer other special arrangements to that individual. (a) The Postal Operations Manual offers information... particular postal services may contact their local postal manager. (d) Response to a request or complaint regarding a special arrangement for postal services. A local postal manager receiving a request or...

  8. 39 CFR 255.7 - Special arrangements for postal services.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... offer other special arrangements to that individual. (a) The Postal Operations Manual offers information... particular postal services may contact their local postal manager. (d) Response to a request or complaint regarding a special arrangement for postal services. A local postal manager receiving a request or...

  9. OBSERVATIONS ON ENGINEERING ASPECTS OF THE BRENTWOOD POSTAL FACILITY FUMIGATION

    EPA Science Inventory

    The paper provides a summary of the four tests of the chlorine dioxide (ClO2) generation and scrubbing system at the 14,000,000 cubic foot Brentwood postal facility in Washington, DC, which had been contaminated with anthrax spores contained in a letter addressed to Senator Thoma...

  10. EMCCD based luminescence imaging system for spatially resolved geo-chronometric and radiation dosimetric applications

    NASA Astrophysics Data System (ADS)

    Chauhan, N.; Adhyaru, P.; Vaghela, H.; Singhvi, A. K.

    2014-11-01

    We report the development of an Electron Multiplier Charge Coupled Device (EMCCD) based luminescence dating system. The system enables position sensitive measurements of luminescence for the estimation of spatially resolved distribution of equivalent dose for complex geological samples. The system includes: 1) a sample stimulation unit (with both thermal and optical stimulations), 2) an optics unit that comprises imaging optics and, 3) a data acquisition and processing unit. The system works in a LabVIEW environment with a graphical user interface (GUI). User specified stimulation protocols enable thermal and optical stimulation in any desired combination. The optics unit images the luminescence on to a EMCCD (512 × 512 pixels, each of 16μm × 16μm size) and maintains a unit magnification. This unit has flexible focusing and a filter housing that enables change of filters combinations without disturbing the setup. Time integrated EMCCD images of luminescence from the sample are acquired as a function of programmable dwell time and these images are processed using indigenously developed MATLAB based programs. Additionally, the programs align the acquired images using a set of control points (identifier features on the images) to a single pixel accuracy. The dose evaluation is based on integrated intensity from selected pixels followed by generation of a growth curve giving luminescence as a function of applied beta doses. Development of this EMCCD camera based luminescence system will enable in-situ luminescence measurements of the samples, without the requirement of separating mineral grains from their matrix. It will also allow age estimation of samples such as lithic artifacts/structures via dating of their surfaces, fusion crust of meteorites, pedogenic carbonates, etc and will additionally open up possibilities of application like testing spatial uniformity of doping in artificial luminescence phosphors, dating/dosimetry of inclusions etc.

  11. Dosimetric evaluation of total marrow irradiation using 2 different planning systems.

    PubMed

    Nalichowski, Adrian; Eagle, Don G; Burmeister, Jay

    2016-01-01

    This study compared 2 different treatment planning systems (TPSs) for quality and efficiency of total marrow irradiation (TMI) plans. The TPSs used in this study were VOxel-Less Optimization (VoLO) (Accuray Inc, Sunnyvale, CA) using helical dose delivery on a Tomotherapy Hi-Art treatment unit and Eclipse (Varian Medical Systems Inc, Palo Alto, CA) using volumetric modulated arc therapy (VMAT) dose delivery on a Varian iX treatment unit. A total dose of 1200cGy was prescribed to cover 95% of the planning target volume (PTV). The plans were optimized and calculated based on a single CT data and structure set using the Alderson Rando phantom (The Phantom Laboratory, Salem, NY) and physician contoured target and organ at risk (OAR) volumes. The OARs were lungs, heart, liver, kidneys, brain, and small bowel. The plans were evaluated based on plan quality, time to optimize the plan and calculate the dose, and beam on time. The resulting mean and maximum doses to the PTV were 1268 and 1465cGy for VoLO and 1284 and 1541cGy for Eclipse, respectively. For 5 of 6 OAR structures the VoLO system achieved lower mean and D10 doses ranging from 22% to 52% and 3% to 44%, respectively. Total computational time including only optimization and dose calculation were 0.9 hours for VoLO and 3.8 hours for Eclipse. These times do not include user-dependent target delineation and field setup. Both planning systems are capable of creating high-quality plans for total marrow irradiation. The VoLO planning system was able to achieve more uniform dose distribution throughout the target volume and steeper dose fall off, resulting in superior OAR sparing. VoLO׳s graphics processing unit (GPU)-based optimization and dose calculation algorithm also allowed much faster creation of TMI plans. PMID:27372384

  12. Evaluation of MLC leaf positioning accuracy for static and dynamic IMRT treatments using DAVID in vivo dosimetric system.

    PubMed

    Karagoz, Gulay; Zorlu, Faruk; Yeginer, Mete; Yildiz, Demet; Ozyigit, Gokhan

    2016-01-01

    Accuracy and precision of leaf positioning in multileaf collimators (MLCs) are significant factors for the accuracy of IMRT treatments. This study aimed to inves-tigate the accuracy and repeatability of the MLC leaf positioning via the DAVID invivo dosimetric system for dynamic and static MLC systems. The DAVID system was designed as multiwire transmission ionization chamber which is placed in accessory holder of linear accelerators. Each wire of DAVID system corresponds to a MLC leaf-pair to verify the leaf positioning accuracy during IMRT treatment and QA. In this study, verifications of IMRT plans of five head and neck (H&N) and five prostate patients treated in a Varian DHX linear accelerator with 80-leaf MLC were performed using DAVID system. Before DAVID-based dosimetry, Electronics Portal Imaging Device (EPID) and PTW 2D ARRAY dosimetry system were used for 2D verification of each plan. The measurements taken by DAVID system in the first day of the treatments were used as reference for the following measurements taken over the next four weeks. The deviations in leaf positioning were evaluated by "Total Deviation (TD)" parameter calculated by DAVID software. The delivered IMRT plans were originally prepared using dynamic MLC method. The same plans were subsequently calculated based on static MLC method with three different intensity levels of five (IL5), 10 (IL10) and 20 (IL20) in order to compare the performances of MLC leaf positioning repeatability for dynamic and static IMRT plans. The leaf positioning accuracy is also evaluated by analyzing DynaLog files based on error histograms and root mean square (RMS) errors of leaf pairs' positions. Moreover, a correlation analysis between simultaneously taken DAVID and EPID measurements and DynaLog file recordings was subsequently performed. In the analysis of DAVID outputs, the overall deviations of dynamic MLC-based IMRT calculated from the deviations of the four weeks were found as 0.55% ± 0.57% and 1.48% ± 0

  13. Evaluation of MLC leaf positioning accuracy for static and dynamic IMRT treatments using DAVID in vivo dosimetric system.

    PubMed

    Karagoz, Gulay; Zorlu, Faruk; Yeginer, Mete; Yildiz, Demet; Ozyigit, Gokhan

    2016-03-08

    Accuracy and precision of leaf positioning in multileaf collimators (MLCs) are significant factors for the accuracy of IMRT treatments. This study aimed to inves-tigate the accuracy and repeatability of the MLC leaf positioning via the DAVID invivo dosimetric system for dynamic and static MLC systems. The DAVID system was designed as multiwire transmission ionization chamber which is placed in accessory holder of linear accelerators. Each wire of DAVID system corresponds to a MLC leaf-pair to verify the leaf positioning accuracy during IMRT treatment and QA. In this study, verifications of IMRT plans of five head and neck (H&N) and five prostate patients treated in a Varian DHX linear accelerator with 80-leaf MLC were performed using DAVID system. Before DAVID-based dosimetry, Electronics Portal Imaging Device (EPID) and PTW 2D ARRAY dosimetry system were used for 2D verification of each plan. The measurements taken by DAVID system in the first day of the treatments were used as reference for the following measurements taken over the next four weeks. The deviations in leaf positioning were evaluated by "Total Deviation (TD)" parameter calculated by DAVID software. The delivered IMRT plans were originally prepared using dynamic MLC method. The same plans were subsequently calculated based on static MLC method with three different intensity levels of five (IL5), 10 (IL10) and 20 (IL20) in order to compare the performances of MLC leaf positioning repeatability for dynamic and static IMRT plans. The leaf positioning accuracy is also evaluated by analyzing DynaLog files based on error histograms and root mean square (RMS) errors of leaf pairs' positions. Moreover, a correlation analysis between simultaneously taken DAVID and EPID measurements and DynaLog file recordings was subsequently performed. In the analysis of DAVID outputs, the overall deviations of dynamic MLC-based IMRT calculated from the deviations of the four weeks were found as 0.55% ± 0.57% and 1.48% ± 0

  14. Development of a three-dimensional model of the human respiratory system for dosimetric use

    PubMed Central

    2013-01-01

    Background Determining the fate of inhaled contaminants in the human respiratory system has challenged scientists for years. Human and animal studies have provided some data, but there is a paucity of data for toxic contaminants and sensitive populations (such as children, elderly, diseased). Methods Three-dimensional modeling programs and publicly available human physiology data have been used to develop a comprehensive model of the human respiratory system. Results The in silico human respiratory system model, which includes the extrathoracic region (nasal, oral, pharyngeal, and laryngeal passages), the upper airways (trachea and main bronchi), the tracheobronchial tree, and branching networks through alveolar region, allows for virtually any variation of airway geometries and disease states. The model allows for parameterization of variables that define the subject’s airways by integrating morphological changes created by disease, age, etc. with a dynamic morphology. Conclusions The model can be used for studies of sensitive populations and the homeland security community, in cases where inhalation studies on humans cannot be conducted with toxic contaminants of interest. PMID:23634755

  15. 76 FR 66766 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

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    ... noticing a recently filed Postal Service request to include a bilateral agreement with Australia Post in... Corporation (Australia Post), which it seeks to include in the Inbound Market Dominant Multi-Service Agreements with Foreign Postal Operators 1 product.\\1\\ The Australia Post Agreement establishes new rates...

  16. 75 FR 45174 - New Postal Product

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    ... a recently-filed Postal Service request to add six Global Expedited Package Services 3 (GEPS 3... filed a notice announcing that it has entered into six additional Global Expedited Package Services 3... Postal Service Filing of Six Functionally Equivalent Global Expedited Package Services 3...

  17. 75 FR 53002 - New Postal Products

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    2010-08-30

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  18. 77 FR 39747 - Changes in Postal Rates

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  20. 78 FR 13713 - New Postal Product

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  1. 78 FR 36795 - New Postal Product

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    2013-06-19

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    2012-08-10

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    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-26

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  4. 78 FR 59734 - New Postal Product

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    2013-09-27

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  5. 75 FR 79054 - New Postal Product

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    2010-12-17

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    2012-11-26

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    2010-12-17

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  8. 77 FR 70491 - New Postal Product

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    2012-11-26

    ... New Postal Product AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is... redacted contract related to the proposed new product under 39 U.S.C. 3632(b)(3) and 39 CFR 3015.5. Id...' Decision No. 11-6, authorizing the new product; Attachment B--a redacted copy of the contract; Attachment...

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  11. 75 FR 1280 - New Postal Product

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  12. 78 FR 63520 - New Postal Product

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    2013-10-24

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  13. 77 FR 58421 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-20

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    2012-01-04

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  15. 76 FR 53983 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-30

    ... agreement, Koninklijke TNT Post BV and TNT Post Pakketservice Benelux BV (TNT Agreement). The Postal Service.... The Postal Service asserts that the Norway Post Agreement and the TNT Agreement incorporate the same cost and market characteristics. Notice at 3. It states that the TNT Agreement includes similar...

  16. Dosimetric advantages of O-ring design radiotherapy system for skull-base tumors.

    PubMed

    Ogura, Kengo; Mizowaki, Takashi; Ishida, Yuichi; Hiraoka, Masahiro

    2014-01-01

    The purpose of this study was to investigate whether a new O-ring design radiotherapy delivery system has advantages in radiotherapy planning for skull-base tumors. Twenty-five patients with skull-base tumors were included in this study. Two plans were made using conventional (Plan A) or new (Plan B) techniques. Plan A consisted of four dynamic conformal arcs (DCAs): two were horizontal, and the other two were from cranial directions. Plan B was created by converting horizontal arcs to those from caudal directions making use of the O-ring design radiotherapy system. The micromultileaf collimators were fitted to cover at least 99% of the planning target volume with prescribed doses, 90% of the dose at the isocenter. The two plans were compared in terms of target homogeneity, conformity, and irradiated volume of normal tissues, using a two-sided paired t-test. For evaluation regarding target coverage, the homogeneity indices defined by the International Commission on Radiation Units and Measurements 83 were 0.099 ± 0.010 (mean ± standard deviation) and 0.092 ± 0.010, the conformity indices defined by the Radiation Therapy Oncology Group were 1.720 ± 0.249 and 1.675 ± 0.239, and the Paddick's conformity indices were 0.585 ± 0.078 and 0.602 ± 0.080, in Plans A and B, respectively. For evaluation of irradiated normal tissue, the Paddick's gradient indices were 3.118 ± 0.283 and 2.938 ± 0.263 in Plans A and B, respectively. All of these differences were statistically significant (p-values < 0.05). The mean doses of optic nerves, eyes, brainstem, and hippocampi were also significantly lower in Plan B. The DCA technique from caudal directions using the new O-ring design radiotherapy system can improve target homogeneity and conformity compared with conventional DCA techniques, and can also decrease the volume of surrounding normal tissues that receives moderate doses. PMID:24710448

  17. Dosimetric advantages of O-ring design radiotherapy system for skull-base tumors.

    PubMed

    Ogura, Kengo; Mizowaki, Takashi; Ishida, Yuichi; Hiraoka, Masahiro

    2014-03-06

    The purpose of this study was to investigate whether a new O-ring design radiotherapy delivery system has advantages in radiotherapy planning for skull-base tumors. Twenty-five patients with skull-base tumors were included in this study. Two plans were made using conventional (Plan A) or new (Plan B) techniques. Plan A consisted of four dynamic conformal arcs (DCAs): two were horizontal, and the other two were from cranial directions. Plan B was created by converting horizontal arcs to those from caudal directions making use of the O-ring design radiotherapy system. The micromultileaf collimators were fitted to cover at least 99% of the planning target volume with prescribed doses, 90% of the dose at the isocenter. The two plans were compared in terms of target homogeneity, conformity, and irradiated volume of normal tissues, using a two-sided paired t-test. For evaluation regarding target coverage, the homogeneity indices defined by the International Commission on Radiation Units and Measurements 83 were 0.099 ± 0.010 (mean ± standard deviation) and 0.092 ± 0.010, the conformity indices defined by the Radiation Therapy Oncology Group were 1.720 ± 0.249 and 1.675 ± 0.239, and the Paddick's conformity indices were 0.585 ± 0.078 and 0.602 ± 0.080, in Plans A and B, respectively. For evaluation of irradiated normal tissue, the Paddick's gradient indices were 3.118 ± 0.283 and 2.938 ± 0.263 in Plans A and B, respectively. All of these differences were statistically significant (p-values < 0.05). The mean doses of optic nerves, eyes, brainstem, and hippocampi were also significantly lower in Plan B. The DCA technique from caudal directions using the new O-ring design radiotherapy system can improve target homogeneity and conformity compared with conventional DCA techniques, and can also decrease the volume of surrounding normal tissues that receives moderate doses.

  18. Neighborhood and postal worker characteristics associated with dog bites in postal workers of the Brazilian National Postal Service in Curitiba.

    PubMed

    de Oliveira, Eduardo Alexandre; Manosso, Rose Maria; Braune, Gisela; Marcenovicz, Priscila Cavalheiro; Kuritza, Leandro Nagae; Ventura, Henrique Larsen Brunow; Paploski, Igor Adolfo Dexheimer; Kikuti, Mariana; Biondo, Alexander Welker

    2013-05-01

    Dog bites are the third most common cause of absenteeism among postal workers of the Brazilian National Postal Service in Southern Brazil, with an average off-work time of approximately two days for each biting episode. The objective of this study was to evaluate the neighborhood characteristics involving dog bites that occurred during work time in postal workers, its impact on work and consequent preventive alternatives. A descriptive and analytical cross-sectional study was designed for all Curitiba postal workers. Data were descriptively analyzed and the hypothesis of correlation between median monthly income, population density and occurrence of dog bites was tested. A total of 34.9% of the postal workers answered the questionnaire and 64.6% of them had been bitten while working. The odds of bites occurring in a neighborhood increase by 1.035 times for every increase in one unit in the population density and decrease by 0.998 times for every increase of US$ 1.00 in the neighborhood median monthly income of the head of the family. The occurrence of dog bites among postal workers in Curitiba is related to income and population density and prevention strategies should address mailbox position and adequate fencing to provide protection for postal workers.

  19. Prevention of transfusion-associated graft-versus-host disease by irradiation: technical aspect of a new ferrous sulphate dosimetric system.

    PubMed

    Del Lama, Lucas Sacchini; de Góes, Evamberto Garcia; Petchevist, Paulo César Dias; Moretto, Edson Lara; Borges, José Carlos; Covas, Dimas Tadeu; de Almeida, Adelaide

    2013-01-01

    Irradiation of whole blood and blood components before transfusion is currently the only accepted method to prevent Transfusion-Associated Graft-Versus-Host-Disease (TA-GVHD). However, choosing the appropriate technique to determine the dosimetric parameters associated with blood irradiation remains an issue. We propose a dosimetric system based on the standard Fricke Xylenol Gel (FXG) dosimeter and an appropriate phantom. The modified dosimeter was previously calibrated using a (60)Co teletherapy unit and its validation was accomplished with a (137)Cs blood irradiator. An ionization chamber, standard FXG, radiochromic film and thermoluminescent dosimeters (TLDs) were used as reference dosimeters to determine the dose response and dose rate of the (60)Co unit. The dose distributions in a blood irradiator were determined with the modified FXG, the radiochromic film, and measurements by TLD dosimeters. A linear response for absorbed doses up to 54 Gy was obtained with our system. Additionally, the dose rate uncertainties carried out with gel dosimetry were lower than 5% and differences lower than 4% were noted when the absorbed dose responses were compared with ionization chamber, film and TLDs.

  20. Prevention of Transfusion-Associated Graft-versus-Host Disease by Irradiation: Technical Aspect of a New Ferrous Sulphate Dosimetric System

    PubMed Central

    Del Lama, Lucas Sacchini; de Góes, Evamberto Garcia; Petchevist, Paulo César Dias; Moretto, Edson Lara; Borges, José Carlos; Covas, Dimas Tadeu; de Almeida, Adelaide

    2013-01-01

    Irradiation of whole blood and blood components before transfusion is currently the only accepted method to prevent Transfusion-Associated Graft-Versus-Host-Disease (TA-GVHD). However, choosing the appropriate technique to determine the dosimetric parameters associated with blood irradiation remains an issue. We propose a dosimetric system based on the standard Fricke Xylenol Gel (FXG) dosimeter and an appropriate phantom. The modified dosimeter was previously calibrated using a 60Co teletherapy unit and its validation was accomplished with a 137Cs blood irradiator. An ionization chamber, standard FXG, radiochromic film and thermoluminescent dosimeters (TLDs) were used as reference dosimeters to determine the dose response and dose rate of the 60Co unit. The dose distributions in a blood irradiator were determined with the modified FXG, the radiochromic film, and measurements by TLD dosimeters. A linear response for absorbed doses up to 54 Gy was obtained with our system. Additionally, the dose rate uncertainties carried out with gel dosimetry were lower than 5% and differences lower than 4% were noted when the absorbed dose responses were compared with ionization chamber, film and TLDs. PMID:23762345

  1. Dosimetric audit in brachytherapy

    PubMed Central

    Bradley, D A; Nisbet, A

    2014-01-01

    Dosimetric audit is required for the improvement of patient safety in radiotherapy and to aid optimization of treatment. The reassurance that treatment is being delivered in line with accepted standards, that delivered doses are as prescribed and that quality improvement is enabled is as essential for brachytherapy as it is for the more commonly audited external beam radiotherapy. Dose measurement in brachytherapy is challenging owing to steep dose gradients and small scales, especially in the context of an audit. Several different approaches have been taken for audit measurement to date: thimble and well-type ionization chambers, thermoluminescent detectors, optically stimulated luminescence detectors, radiochromic film and alanine. In this work, we review all of the dosimetric brachytherapy audits that have been conducted in recent years, look at current audits in progress and propose required directions for brachytherapy dosimetric audit in the future. The concern over accurate source strength measurement may be essentially resolved with modern equipment and calibration methods, but brachytherapy is a rapidly developing field and dosimetric audit must keep pace. PMID:24807068

  2. 75 FR 22189 - Obtaining Information From the Postal Service

    Federal Register 2010, 2011, 2012, 2013, 2014

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    ... Commission 39 CFR Parts 3001 and 3005 Obtaining Information From the Postal Service; Final Rule #0;#0;Federal... COMMISSION 39 CFR Parts 3001 and 3005 Obtaining Information From the Postal Service AGENCY: Postal Regulatory... information from the Postal Service. Their adoption is consistent with Commission obligations under a...

  3. 77 FR 1089 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-09

    ...The Commission is noticing a recently-filed Postal Service request to add a Global Direct Contracts 1 contract to the competitive product list. This notice addresses procedural steps associated with the...

  4. 77 FR 61307 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-09

    .... The Postal Service proposes to move the machinable and irregular cost worksheets contained in the... cost model and to relabel the worksheets as ``Lightweight Parcel Select.'' Id. at 3. The Commission,...

  5. 76 FR 54510 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... ``International Business Reply Service (IBRS) Competitive Contract 3'' product offering. This document invites... into an additional International Business Reply Service (IBRS) Competitive contract.\\1\\ The Postal... International Business Reply Service Competitive Contract 3 Negotiated Service Agreement, August 19,...

  6. Fair and Equitable Postal Service Access Act

    THOMAS, 112th Congress

    Rep. Moore, Gwen [D-WI-4

    2011-09-15

    10/03/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  7. 39 CFR 3001.117 - Posting of documents by Postal Service for inspection by affected postal patrons.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Posting of documents by Postal Service for... PERSONNEL RULES OF PRACTICE AND PROCEDURE Rules Applicable to Appeals of Postal Service Determinations To Close or Consolidate Post Offices § 3001.117 Posting of documents by Postal Service for inspection...

  8. Dosimetric characterization of a multileaf collimator for a new four-dimensional image-guided radiotherapy system with a gimbaled x-ray head, MHI-TM2000

    SciTech Connect

    Nakamura, Mitsuhiro; Sawada, Akira; Ishihara, Yoshitomo; Takayama, Kenji; Mizowaki, Takashi; Kaneko, Shuji; Yamashita, Mikiko; Tanabe, Hiroaki; Kokubo, Masaki; Hiraoka, Masahiro

    2010-09-15

    Purpose: To present the dosimetric characterization of a multileaf collimator (MLC) for a new four-dimensional image-guided radiotherapy system with a gimbaled x-ray head, MHI-TM2000. Methods: MHI-TM2000 has an x-ray head composed of an ultrasmall linear accelerator guide and a system-specific MLC. The x-ray head can rotate along the two orthogonal gimbals (pan and tilt rotations) up to {+-}2.5 deg., which swings the beam up to {+-}41.9 mm in each direction from the isocenter on the isocenter plane perpendicular to the beam. The MLC design is a single-focus type, has 30 pairs of 5 mm thick leaves at the isocenter, and produces a maximum field size of 150x150 mm{sup 2}. Leaf height and length are 110 and 260 mm, respectively. Each leaf end is circular, with a radius of curvature of 370 mm. The distance that each leaf passes over the isocenter is 77.5 mm. Radiation leakage between adjacent leaves is minimized by an interlocking tongue-and-groove (T and G) arrangement with the height of the groove part 55 mm. The dosimetric characterizations including field characteristics, leaf position accuracy, leakage, and T and G effect were evaluated using a well-commissioned 6 MV photon beam, EDR2 films (Kodak, Rochester, NY), and water-equivalent phantoms. Furthermore, the field characteristics and leaf position accuracy were evaluated under conditions of pan or tilt rotation. Results: The differences between nominal and measured field sizes were within {+-}0.5 mm. Although the penumbra widths were greater with wider field size, the maximum width was <5.5 mm even for the fully opened field. Compared to the results of field characteristics without pan or tilt rotation, the variation in field size, penumbra width, flatness, and symmetry was within {+-}1 mm/1% at the maximum pan or tilt rotational angle. The leaf position accuracy was 0.0{+-}0.1 mm, ranging from -0.3 to 0.2 mm at four gantry angles of 0 deg., 90 deg., 180 deg., and 270 deg. with and without pan or tilt rotation

  9. Effect of e-mail versus postal reminders for mammogram screening.

    PubMed

    Chaudhry, Rajeev; Cabanela, Rosa; Rahman, Ahmed; McMurtry, Erin; Leutink, Dorinda; Scheitel, Sidna; Naessens, James M

    2006-01-01

    A randomized controlled trial was undertaken to measure the efficacy of a patient reminder system for females age 40 - 75 in a Midwestern primary care practice. A subset of the population whose email addresses were known was further randomized to measure the effect of email versus postal reminders. A statistically significant increase in completion rates was observed in the intervention group while no difference was found between the email and postal mail groups.

  10. 39 CFR 762.31 - Disbursement postal money orders issued to deceased payees.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Disbursement postal money orders issued to deceased payees. 762.31 Section 762.31 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing...

  11. 39 CFR 762.30 - Disbursement postal money orders issued to incompetent payees.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Disbursement postal money orders issued to incompetent payees. 762.30 Section 762.30 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing...

  12. 39 CFR 762.44 - Receipt or recovery of original disbursement postal money order.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... postal money order. 762.44 Section 762.44 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Issuance of Substitutes for Lost, Destroyed, Mutilated, and Defaced Disbursement Postal Money Orders § 762.44 Receipt or...

  13. Dosimetric comparison of Linac-based (BrainLAB®) and robotic radiosurgery (CyberKnife ®) stereotactic system plans for acoustic schwannoma.

    PubMed

    Dutta, Debnarayan; Balaji Subramanian, S; Murli, V; Sudahar, H; Gopalakrishna Kurup, P G; Potharaju, Mahadev

    2012-02-01

    A dosimetric comparison of linear accelerator (LA)-based (BrainLAB) and robotic radiosurgery (RS) (CyberKnife) systems for acoustic schwannoma (Acoustic neuroma, AN) was carried out. Seven patients with radiologically confirmed unilateral AN were planned with both an LA-based (BrainLAB) and robotic RS (CyberKnife) system using the same computed tomography (CT) dataset and contours. Gross tumour volume (GTV) was contoured on post-contrast magnetic resonance imaging (MRI) scan [planning target volume (PTV) margin 2 mm]. Planning and calculation were done with appropriate calculation algorithms. The prescribed isodose in both systems was considered adequate to cover at least 95% of the contoured target. Plan evaluations were done by examining the target coverage by the prescribed isodose line, and high- and low-dose volumes. Isodose plans and dose volume histograms generated by the two systems were compared. There was no statistically significant difference between the contoured volumes between the systems. Tumour volumes ranged from 380 to 3,100 mm(3). Dose prescription was 13-15 Gy in single fraction (median prescribed isodose 85%). There were no significant differences in conformity index (CI) (0.53 versus 0.58; P = 0.225), maximum brainstem dose (4.9 versus 4.7 Gy; P = 0.935), 2.5-Gy volume (39.9 versus 52.3 cc; P = 0.238) or 5-Gy volume (11.8 versus 16.8 cc; P = 0.129) between BrainLAB and CyberKnife system plans. There were statistically significant differences in organs at risk (OAR) doses, such as mean cochlear dose (6.9 versus 5.4 Gy; P = 0.001), mean mesial temporal dose (2.6 versus 1.7 Gy; P = 0.07) and high-dose (10 Gy) volume (3.2 versus 5.2 cc; P = 0.017). AN patients planned with the CyberKnife system had superior OAR (cochlea and mesial temporal lobe) sparing compared with those planned with the Linac-based system. Further evaluation of these findings in prospective studies with clinical correlation will provide actual clinical benefit from the

  14. 39 CFR 255.7 - Special arrangements for postal services.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PERSONS WITH DISABILITIES TO POSTAL SERVICE PROGRAMS, ACTIVITIES, FACILITIES, AND ELECTRONIC AND INFORMATION TECHNOLOGY § 255.7 Special arrangements for postal services. Members of the public who are...

  15. 76 FR 77483 - Nationwide Change in Postal Delivery Service Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-13

    ... in the Direct Testimony of David E. Williams on behalf of the United States Postal Service (USPS-T-1... behalf of United States Postal Service (USPS-T-5), and Direct Testimony of Cheryl D. Martin on behalf...

  16. 39 CFR 1.1 - Establishment of the U.S. Postal Service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Establishment of the U.S. Postal Service. 1.1 Section 1.1 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE POSTAL POLICY (ARTICLE I) § 1.1 Establishment of the U.S. Postal Service. The U.S. Postal Service...

  17. 39 CFR 1.1 - Establishment of the U.S. Postal Service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Establishment of the U.S. Postal Service. 1.1 Section 1.1 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE POSTAL POLICY (ARTICLE I) § 1.1 Establishment of the U.S. Postal Service. The U.S. Postal Service...

  18. 39 CFR 1.1 - Establishment of the U.S. Postal Service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Establishment of the U.S. Postal Service. 1.1 Section 1.1 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE POSTAL POLICY (ARTICLE I) § 1.1 Establishment of the U.S. Postal Service. The U.S. Postal Service...

  19. 39 CFR 1.1 - Establishment of the U.S. Postal Service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Establishment of the U.S. Postal Service. 1.1 Section 1.1 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE POSTAL POLICY (ARTICLE I) § 1.1 Establishment of the U.S. Postal Service. The U.S. Postal Service...

  20. 39 CFR 1.1 - Establishment of the U.S. Postal Service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Establishment of the U.S. Postal Service. 1.1 Section 1.1 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE POSTAL POLICY (ARTICLE I) § 1.1 Establishment of the U.S. Postal Service. The U.S. Postal Service...

  1. 76 FR 80985 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-27

    ... noticing a recently-filed Postal Service request to enter into an outstanding International Business Reply..., pursuant to 39 CFR 3015.5, of contingency prices under an outstanding International Business Reply Service... under Functionally Equivalent International Business Reply Service Competitive Contract 1...

  2. 78 FR 4174 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-18

    ... is noticing a recent Postal Service filing concerning the addition of Priority Mail Contract 51 to... Priority Mail Contract 51 to the competitive product list.\\1\\ It asserts that Priority Mail Contract 51 is... Service to Add Priority Mail Contract 51 to Competitive Product List and Notice of Filing (Under Seal)...

  3. 75 FR 12445 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-16

    ...: The Commission is adding International Business Reply Service Competitive Contract 2 to the Competitive Product List. This action is consistent with a postal reform law. Republication of the Market... History, 74 FR 49823 (September 29, 2009). Table of Contents I. Introduction II. Background III....

  4. 75 FR 7201 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-18

    ... is adding Priority Mail Contract 24 to the Competitive Product List. This action is consistent with changes in a postal reform law. Republication of the lists of market dominant and competitive products is...-6820 or stephen.sharfman@prc.gov . SUPPLEMENTARY INFORMATION: Regulatory History, 74 FR 31374 (July...

  5. 78 FR 76863 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-19

    ...The Commission is noticing a recent Postal Service filing concerning a contract with Australia Post for the delivery of inbound Air CP and Express Mail Services (EMS). This notice informs the public of the filing, invites public comment, and takes other administrative...

  6. 75 FR 47033 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-04

    ... a recently-filed Postal Service request to add six Global Expedited Package Services 3 contracts to... notice announcing that it has entered into six additional Global Expedited Package Services 3 (GEPS 3... Filing of Six Functionally Equivalent Global Expedited Package Services 3 Negotiated Service...

  7. 75 FR 880 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-06

    ... rate for mail acceptance within the United States and transportation to a receiving country, with the...' Decision in that docket. The instant contract. The Postal Service filed the instant agreement pursuant to... Order No. 153.\\3\\ Id. It submitted the contract and supporting material under seal, and attached...

  8. 75 FR 45176 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... packaging for eligible Priority Mail items mailed by the shipper. The Postal Service filed much of the supporting materials, including the specific Priority Mail Contract 25, under seal. It maintains that the...-public treatment of materials to maintain redacted portions of the contract and supporting document...

  9. 75 FR 78915 - Conduct on Postal Property

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-17

    ... in 39 CFR 232.1. 1. Paragraph (f) Gambling: The prohibition of lottery ticket sales contains an... Conduct on postal property. * * * * * (f) Gambling. Participating in games for money or other personal property, the operation of gambling devices, the conduct of a lottery or pool, or the selling or...

  10. 75 FR 166 - Postal Product Price Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-04

    .... CP2009-29, exchange rate fluctuations and changes in the amount Canada Post Corporation charges the Postal Service for services. Id. at 7. For rate changes based on these types of objective, external... plans on changing rates for the Global Plus 2 contract at issue in this docket. It is unclear,...

  11. 78 FR 33451 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-04

    ... Supporting Justification, Frank Cebello, Executive Director, Global Business Management, asserts that the... and medium-size businesses. Request at 5. Governors' Decision No. 10-1 established prices and...' Decision No. 11-6 authorizes Postal Service management to prepare and present to the Commission...

  12. 75 FR 45174 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ..., rate schedules, a management analysis, and certification that prices satisfy applicable pricing criteria. Attachment 3 is a Statement of Justification by the Executive Director, Global Business Management. Attachment 4 is a representative agreement between the Postal Service and a customer of...

  13. 75 FR 471 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-05

    ... noticing a recently-filed Postal Service request to add Global Direct Contracts 1 to the Competitive... additional Global Direct contract, and seeks to add it as Global Direct Contracts 1 to the Competitive... previously submitted Global Direct Contracts and is supported by Governors' Decision No. 08- 10,...

  14. 76 FR 10410 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-24

    ... Justification, Jo Ann Miller, former Director, Global Business Development, asserts that the services to be... noticing a recently-filed Postal Service request to add International Business Reply Service (IBRS... International Business Reply Service (IBRS) Competitive Contract 3 to the competitive product list...

  15. 75 FR 7634 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-22

    ... Director, Global Business Development, asserts that the services to be provided under the contracts will... the public that the Postal Service has filed a request to add International Business Reply Service...-789-6820 or prc.gov ">stephen.sharfman@ prc.gov . SUPPLEMENTARY INFORMATION: Regulatory History, 74...

  16. 77 FR 67840 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-14

    ... to the competitive product list. This notice informs the public of the filing, invites public comment... First-Class Package Service Contract 26 to the competitive product list.\\1\\ The Postal Service asserts... the Competitive Product List and Notice of Filing (Under Seal) of Unredacted Governors'...

  17. 78 FR 79023 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... competitive product list. This notice informs the public of the filing, invites public comment, and takes... supporting information to add Priority Mail Contract 73 to the competitive product list.\\1\\ The Postal... Product List and Notice of Filing (Under Seal) of Unredacted Governors' Decision, Contract, and...

  18. 77 FR 67839 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-14

    ... competitive product list. This notice informs the public of the filing, ] invites public comment, and takes... Mail Contract 48 to the competitive product list.\\1\\ The Postal Service indicates that the instant... List and Notice of Filing (Under Seal) of Unredacted Governors' Decision, Contract, and Supporting...

  19. 78 FR 76334 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-17

    ... competitive product list. This notice informs the public of the filings, invites public comment, and takes... Contract 72 to the competitive product list.\\1\\ The Postal Service asserts that Priority Mail Contract 72 is a competitive product ``not of general applicability'' within the meaning of 39 U.S.C....

  20. 78 FR 76332 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-17

    ... competitive product list. This notice informs the public of the filings, invites public comment, and takes... Contract 71 to the competitive product list.\\1\\ The Postal Service asserts ] that Priority Mail Contract 71 is a competitive product ``not of general applicability'' within the meaning of 39 U.S.C....

  1. 78 FR 39783 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-02

    ... noticing a recently-filed Postal Service request to add a new product to the competitive product list. This... and associated supporting information to add Priority Mail Contract 60 to the competitive product list.\\1\\ It asserts that Priority Mail Contract 60 is a competitive product ``not of general...

  2. 76 FR 22157 - Postal Service Rate Adjustment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... flats that include, in or on the mailpiece, a two dimensional barcode readable by mobile smart phones.... Id. The Postal Service requires that the barcode must be two dimensional, and notes that one dimensional barcodes, though readable by smart phones, are not eligible to receive the discount. Id....

  3. 39 CFR 232.1 - Conduct on postal property.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... this section. Editorial Note: For Federal Register citations affecting § 232.1, see the List of CFR... 39 Postal Service 1 2010-07-01 2010-07-01 false Conduct on postal property. 232.1 Section 232.1... § 232.1 Conduct on postal property. (a) Applicability. This section applies to all real property...

  4. 75 FR 31702 - General Information on Postal Service

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-04

    ... Issue of the DMM contains all Postal Service domestic mailing standards. This issue continues to (1... version available via Postal Explorer http://pe.usps.com . List of Subjects in 39 CFR Part 111... POSTAL SERVICE 0 1. The authority citation for 39 CFR Part 111 continues to read as follows: Authority:...

  5. 39 CFR 601.104 - Postal purchasing authority.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Postal purchasing authority. 601.104 Section 601...: INTELLECTUAL PROPERTY RIGHTS OTHER THAN PATENTS PURCHASING OF PROPERTY AND SERVICES § 601.104 Postal purchasing..., or terminating any contract regarding the acquisition of property, services, and related...

  6. 39 CFR 255.8 - Access to postal facilities.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... consistent with efficient postal operations. In determining whether modifications not legally required should... the ABA, may be made to the local postal manager of the facility involved. (2) The local postal manager's response to a request or complaint regarding an alteration to a facility will be made...

  7. 39 CFR 601.104 - Postal purchasing authority.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Postal purchasing authority. 601.104 Section 601...: INTELLECTUAL PROPERTY RIGHTS OTHER THAN PATENTS PURCHASING OF PROPERTY AND SERVICES § 601.104 Postal purchasing..., or terminating any contract regarding the acquisition of property, services, and related...

  8. 39 CFR 762.25 - Reclamation of amounts of paid disbursement postal money orders.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Reclamation of amounts of paid disbursement postal money orders. 762.25 Section 762.25 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT..., Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.25 Reclamation of amounts...

  9. 39 CFR 762.25 - Reclamation of amounts of paid disbursement postal money orders.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... money orders. 762.25 Section 762.25 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.25 Reclamation of amounts...

  10. 39 CFR 762.14 - Amounts for which disbursement postal money orders may be issued.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Amounts for which disbursement postal money orders... OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS General, Definitions, Issuance § 762.14 Amounts for which disbursement postal money orders may be issued. Disbursement Postal...

  11. 39 CFR 762.29 - Endorsement of disbursement postal money orders by payees.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Endorsement of disbursement postal money orders by...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.29 Endorsement of disbursement postal...

  12. 39 CFR 762.29 - Endorsement of disbursement postal money orders by payees.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Endorsement of disbursement postal money orders by...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.29 Endorsement of disbursement postal...

  13. 39 CFR 762.31 - Disbursement postal money orders issued to deceased payees.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Disbursement postal money orders issued to... OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.31 Disbursement postal...

  14. 39 CFR 762.25 - Reclamation of amounts of paid disbursement postal money orders.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... money orders. 762.25 Section 762.25 Postal Service UNITED STATES POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.25 Reclamation of amounts...

  15. 39 CFR 762.14 - Amounts for which disbursement postal money orders may be issued.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Amounts for which disbursement postal money orders... OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS General, Definitions, Issuance § 762.14 Amounts for which disbursement postal money orders may be issued. Disbursement Postal...

  16. 39 CFR 762.30 - Disbursement postal money orders issued to incompetent payees.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Disbursement postal money orders issued to... OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.30 Disbursement postal...

  17. SU-E-T-132: Dosimetric Impact of Positioning Errors in Hypo-Fractionated Cranial Radiation Therapy Using Frameless Stereotactic BrainLAB System

    SciTech Connect

    Keeling, V; Jin, H; Ali, I; Ahmad, S

    2014-06-01

    Purpose: To determine dosimetric impact of positioning errors in the stereotactic hypo-fractionated treatment of intracranial lesions using 3Dtransaltional and 3D-rotational corrections (6D) frameless BrainLAB ExacTrac X-Ray system. Methods: 20 cranial lesions, treated in 3 or 5 fractions, were selected. An infrared (IR) optical positioning system was employed for initial patient setup followed by stereoscopic kV X-ray radiographs for position verification. 6D-translational and rotational shifts were determined to correct patient position. If these shifts were above tolerance (0.7 mm translational and 1° rotational), corrections were applied and another set of X-rays was taken to verify patient position. Dosimetric impact (D95, Dmin, Dmax, and Dmean of planning target volume (PTV) compared to original plans) of positioning errors for initial IR setup (XC: Xray Correction) and post-correction (XV: X-ray Verification) was determined in a treatment planning system using a method proposed by Yue et al. (Med. Phys. 33, 21-31 (2006)) with 3D-translational errors only and 6D-translational and rotational errors. Results: Absolute mean translational errors (±standard deviation) for total 92 fractions (XC/XV) were 0.79±0.88/0.19±0.15 mm (lateral), 1.66±1.71/0.18 ±0.16 mm (longitudinal), 1.95±1.18/0.15±0.14 mm (vertical) and rotational errors were 0.61±0.47/0.17±0.15° (pitch), 0.55±0.49/0.16±0.24° (roll), and 0.68±0.73/0.16±0.15° (yaw). The average changes (loss of coverage) in D95, Dmin, Dmax, and Dmean were 4.5±7.3/0.1±0.2%, 17.8±22.5/1.1±2.5%, 0.4±1.4/0.1±0.3%, and 0.9±1.7/0.0±0.1% using 6Dshifts and 3.1±5.5/0.0±0.1%, 14.2±20.3/0.8±1.7%, 0.0±1.2/0.1±0.3%, and 0.7±1.4/0.0±0.1% using 3D-translational shifts only. The setup corrections (XC-XV) improved the PTV coverage by 4.4±7.3% (D95) and 16.7±23.5% (Dmin) using 6D adjustment. Strong correlations were observed between translation errors and deviations in dose coverage for XC. Conclusion

  18. Career Education Program: Geneva Area City Schools. [Grade 2 Units: Postal Services, Our Homes, Clothing, Community Helpers, and Custodians In Our Lives].

    ERIC Educational Resources Information Center

    Geneva Area City Schools, OH.

    Five curriculum units for the second grade level focus on: (1) clothing producers and suppliers, and the clothing industry; (2) postal service workers and the postal system; (3) janitorial workers; (4) workers who build, furnish, and maintain homes and the housing industry; and (5) various community workers. Behavioral unit objectives emphasize…

  19. 39 CFR 3007.21 - Content of the Postal Service application for non-public treatment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-public treatment. 3007.21 Section 3007.21 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL TREATMENT OF NON-PUBLIC MATERIALS PROVIDED BY THE POSTAL SERVICE § 3007.21 Content of the Postal Service application for non-public treatment. (a) Whenever the Postal Service files non-public materials with...

  20. 39 CFR 3007.21 - Content of the Postal Service application for non-public treatment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-public treatment. 3007.21 Section 3007.21 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL TREATMENT OF NON-PUBLIC MATERIALS PROVIDED BY THE POSTAL SERVICE § 3007.21 Content of the Postal Service application for non-public treatment. (a) Whenever the Postal Service files non-public materials with...

  1. 39 CFR 235.1 - Postal Service to the Armed Forces.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Postal Service to the Armed Forces. 235.1 Section... LIAISON § 235.1 Postal Service to the Armed Forces. (a) Publication 38, Postal Agreement with the... Armed Forces. (b) The Chief Inspector is responsible for military liaison. (c) Postal inspectors...

  2. 39 CFR 235.1 - Postal Service to the Armed Forces.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Postal Service to the Armed Forces. 235.1 Section... LIAISON § 235.1 Postal Service to the Armed Forces. (a) Publication 38, Postal Agreement with the... Armed Forces. (b) The Chief Inspector is responsible for military liaison. (c) Postal inspectors...

  3. 39 CFR 255.3 - Nondiscrimination under any program or activity conducted by the Postal Service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Nondiscrimination under any program or activity conducted by the Postal Service. 255.3 Section 255.3 Postal Service UNITED STATES POSTAL SERVICE ORGANIZATION AND ADMINISTRATION ACCESS OF PERSONS WITH DISABILITIES TO POSTAL SERVICE PROGRAMS, ACTIVITIES, FACILITIES, AND ELECTRONIC AND...

  4. 39 CFR 235.1 - Postal Service to the Armed Forces.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Postal Service to the Armed Forces. 235.1 Section... LIAISON § 235.1 Postal Service to the Armed Forces. (a) Publication 38, Postal Agreement with the... Armed Forces. (b) The Chief Inspector is responsible for military liaison. (c) Postal inspectors...

  5. 39 CFR 235.1 - Postal Service to the Armed Forces.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Postal Service to the Armed Forces. 235.1 Section... LIAISON § 235.1 Postal Service to the Armed Forces. (a) Publication 38, Postal Agreement with the... Armed Forces. (b) The Chief Inspector is responsible for military liaison. (c) Postal inspectors...

  6. 39 CFR 235.1 - Postal Service to the Armed Forces.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Postal Service to the Armed Forces. 235.1 Section... LIAISON § 235.1 Postal Service to the Armed Forces. (a) Publication 38, Postal Agreement with the... Armed Forces. (b) The Chief Inspector is responsible for military liaison. (c) Postal inspectors...

  7. 39 CFR 762.27 - Processing of disbursement postal money orders by Federal Reserve Banks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Processing of disbursement postal money orders by... DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.27 Processing...

  8. 39 CFR 762.28 - Release of original disbursement postal money orders.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Release of original disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.28 Release of original disbursement...

  9. 39 CFR 762.43 - Issuance of substitute disbursement postal money order.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Issuance of substitute disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Issuance of Substitutes for Lost, Destroyed, Mutilated, and Defaced Disbursement Postal Money Orders § 762.43 Issuance of substitute disbursement...

  10. 39 CFR 762.43 - Issuance of substitute disbursement postal money order.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Issuance of substitute disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Issuance of Substitutes for Lost, Destroyed, Mutilated, and Defaced Disbursement Postal Money Orders § 762.43 Issuance of substitute disbursement...

  11. 39 CFR 762.28 - Release of original disbursement postal money orders.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Release of original disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.28 Release of original disbursement...

  12. 39 CFR 762.43 - Issuance of substitute disbursement postal money order.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Issuance of substitute disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Issuance of Substitutes for Lost, Destroyed, Mutilated, and Defaced Disbursement Postal Money Orders § 762.43 Issuance of substitute disbursement...

  13. 39 CFR 762.28 - Release of original disbursement postal money orders.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Release of original disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.28 Release of original disbursement...

  14. 39 CFR 762.28 - Release of original disbursement postal money orders.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Release of original disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.28 Release of original disbursement...

  15. 39 CFR 762.27 - Processing of disbursement postal money orders by Federal Reserve Banks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Processing of disbursement postal money orders by... DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.27 Processing...

  16. 39 CFR 762.28 - Release of original disbursement postal money orders.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Release of original disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Endorsements, Payment, Guaranties, Warranties and Processing of Disbursement Postal Money Orders § 762.28 Release of original disbursement...

  17. 39 CFR 762.43 - Issuance of substitute disbursement postal money order.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Issuance of substitute disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Issuance of Substitutes for Lost, Destroyed, Mutilated, and Defaced Disbursement Postal Money Orders § 762.43 Issuance of substitute disbursement...

  18. 39 CFR 762.43 - Issuance of substitute disbursement postal money order.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Issuance of substitute disbursement postal money...; DISBURSEMENT POSTAL MONEY ORDERS DISBURSEMENT POSTAL MONEY ORDERS Issuance of Substitutes for Lost, Destroyed, Mutilated, and Defaced Disbursement Postal Money Orders § 762.43 Issuance of substitute disbursement...

  19. Electronic Mail: Defining a Role for the U.S. Postal Service.

    ERIC Educational Resources Information Center

    McLaughlin, John F.

    Threatened by competitive diversification and by increasing costs, the United States Postal Service has investigated two potential cost reducing systems: (1) a microsystem which would provide electronic facsimile transmission between major markets and (2) a macrosystem which could take digital input such as utility bills and deliver a hardcopy to…

  20. SU-E-T-136: Dosimetric Robustness of a Magnetic Resonance Imaging Guided Radiation Therapy (MR-IGRT) System

    SciTech Connect

    Rodriguez, V; Green, O; Wooten, H; Kashani, R; Mutic, S; Li, H; Dempsey, J

    2014-06-01

    Purpose: To test the radiation delivery robustness of the first MR-IGRT system using a commercial cylindrical diode array detector (ArcCHECK) and an ionization thimble chamber (Exradin A18). Methods: The MR-IGRT system is composed of three evenly spaced Co-60 sources on a rotating gantry located between two magnet halves. The collimator for each source consists of 30 doubly-focused leaf pairs that allow the system to deliver both conformal and intensity modulated (IMRT) treatment plans. The system's delivery robustness was tested over a span of 6 months from September 2013 through February 2014. This was achieved by repeatedly delivering 10 patient plans. These plans consisted of 2 conformal prostates, 2 IMRT prostates, 2 IMRT head and neck, 2 IMRT breast, 1 IMRT pancreas, and 1 IMRT bladder. The plans were generated with the system's treatment planning software. Once the plans were generated, quality assurance plans were created on a digital ArcCHECK dataset. The ArcCHECK used for testing was specially designed to be MR-compatible by moving the power supply outside of the magnetic field. The A18 ionization chamber was placed in a custom plastic plug insert in the center of the ArcCHECK. Gamma analysis was used with the ArcCHECK for relative dose evaluating both 3%/3mm and 2%/2mm. Absolute point dose was compared between ion chamber measurement and treatment plan. Results: The ArcCHECK passing rate remained constant over the 6 month period. The average passing rate for 3%/3mm and 2%/2mm analysis was 98.6% ± 0.7 and 88.8% ± 2.9, respectively. The ion chamber measurements showed little variation with an average percent difference between planned dose verses measured dose of 0.9% ± 0.7. Conclusion: Minimal differences were noted in the delivery of the 10 patient plans. Over a period that included acceptance testing, commissioning, and clinical deliveries, the MR-IGRT system remained consistent in radiation delivery.

  1. Electronic tissue compensation achieved with both dynamic and static multileaf collimator in eclipse treatment planning system for Clinac 6 EX and 2100 CD Varian linear accelerators: Feasibility and dosimetric study

    PubMed Central

    Kinhikar, Rajesh A.; Sharma, Pramod K.; Patkar, Sachin; Tambe, Chandrashekhar M.; Deshpande, Deepak D.

    2007-01-01

    Dynamic multileaf collimator (DMLC) and static multileaf collimator (SMLC), along with three-dimensional treatment planning system (3-D TPS), open the possibility of tissue compensation. A method using electronic tissue compensator (ETC) has been implemented in Eclipse 3-D TPS (V 7.3, Varian Medical Systems, Palo Alto, USA) at our center. The ETC was tested for head and neck conformal radiotherapy planning. The purpose of this study was to verify the feasibility of DMLC and SMLC in head and neck field irradiation for delivering homogeneous dose in the midplane at a pre-defined depth. In addition, emphasis was given to the dosimetric aspects in commissioning ETC in Eclipse. A Head and Neck Phantom (The Phantom Laboratory, USA) was used for the dosimetric verification. Planning was carried out for both DMLC and SMLC ETC plans. The dose calculated at central axis by eclipse with DMLC and SMLC was noted. This was compared with the doses measured on machine with ion chamber and thermoluminescence dosimetry (TLD). The calculated isodose curves and profiles were compared with the measured ones. The dose profiles along the two major axes from Eclipse were also compared with the profiles obtained from Amorphous Silicon (AS500) Electronic portal imaging device (EPID) on Clinac 6 EX machine. In uniform dose regions, measured dose values agreed with the calculated doses within 3%. Agreement between calculated and measured isodoses in the dose gradient zone was within 3 mm. The isodose curves and the profiles were found to be in good agreement with the measured curves and profiles. The measured and the calculated dose profiles along the two major axes were flat for both DMLC and SMLC. The dosimetric verification of ETC for both the linacs demonstrated the feasibility and the accuracy of the ETC treatment modality for achieving uniform dose distributions. Therefore, ETC can be used as a tool in head and neck treatment planning optimization for improved dose uniformity. PMID

  2. 75 FR 69142 - Postal Rate and Classification Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-10

    ... addresses the comment process and other matters that pertain to the planned changes. DATES: Supplemental... Postal Rate and Classification Changes AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The... its intention of planned rate and classification changes rates for certain competitive domestic...

  3. 12 CFR 7.1010 - Postal service by national bank.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Postal service by national bank. 7.1010 Section 7.1010 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Bank Powers § 7.1010 Postal service by national bank. (a) General. A national bank may...

  4. 78 FR 12801 - New Postal Product; Negotiated Service Agreement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-25

    ... Agreement is scheduled to expire 2 years after its effective date but may be terminated earlier by either...-identifying information be extended indefinitely, instead of ending after 10 years. Id. at 7. II. Notice of... New Postal Product; Negotiated Service Agreement AGENCY: Postal Regulatory Commission. ACTION:...

  5. 12 CFR 7.1010 - Postal service by national bank.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 1 2013-01-01 2013-01-01 false Postal service by national bank. 7.1010 Section 7.1010 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Bank Powers § 7.1010 Postal service by national bank. (a) General. A national bank may...

  6. 78 FR 51678 - Market Tests of Experimental Postal Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ... 39 CFR Parts 3001 and 3035 Market Tests of Experimental Postal Products AGENCY: Postal Regulatory... Service filings concerning market tests of experimental products. The proposed rules address the contents of market test filings, describe how the filings will be reviewed, and discuss related matters....

  7. 77 FR 63899 - New Postal Product; Negotiated Service Agreement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-17

    ... Mail Contract 44 to the competitive product list. This notice provides public notice of the Postal... list.\\1\\ The Postal Service asserts that Priority Mail Contract 44 is a competitive product ``not of... 44 to Competitive Product List and Notice of Filing (Under Seal) of Unredacted Governors'...

  8. SU-D-18A-06: Variation of Controlled Breath Hold From CT Simulation to Treatment and Its Dosimetric Impact for Left-Sided Breast Radiotherapy with a Real-Time Optical Tracking System

    SciTech Connect

    Mittauer, K; Deraniyagala, R; Li, J; Lu, B; Liu, C; Lightsey, J; Yan, G

    2014-06-01

    Purpose: Different breath-hold (BH) maneuvers (abdominal breathing vs. chest breathing) during CT simulation and treatment can lead to chest wall positional variation. The purpose of this study is to quantify the variation of active breathing control (ABC)-assisted BH and estimate its dosimetric impact for left-sided whole-breast radiotherapy with a real-time optical tracking system (OTS). Methods: Seven breast cancer patients were included. An in-house OTS tracked an infrared (IR) marker affixed over the xiphoid process of the patient at CT simulation and throughout the treatment course to measure BH variations. Correlation between the IR marker and the breast was studied for dosimetric purposes. The positional variations of 860 BHs were retrospectively incorporated into treatment plans to assess their dosimetric impact on breast and cardiac organs (heart and left anterior descending artery [LAD]). Results: The mean intrafraction variations were 2.8 mm, 2.7 mm, and 1.6 mm in the anteroposterior (AP), craniocaudal (CC), and mediolateral (ML) directions, respectively. Mean stability in any direction was within 1.5 mm. A general trend of BH undershoot at treatment relative to CT simulation was observed with an average of 4.4 mm, 3.6 mm, and 0.1 mm in the AP, CC, and ML directions, respectively. Undershoot up to 12.6 mm was observed for individual patients. The difference between the planned and delivered dose to breast targets was negligible. The average planned/delivered mean heart doses, mean LAD doses, and max LAD doses were 1.4/2.1, 7.4/15.7, and 18.6/31.0 Gy, respectively. Conclusion: Systematic undershoot was observed in ABC-assisted BHs from CT simulation to treatment. Its dosimetric impact on breast coverage was minimized with image guidance, but the benefits of cardiac organ sparing were degraded. A real-time tracking system can be used in junction with the ABC device to improve BH reproducibility.

  9. Dosimetric Verification of the System of Planning Brainscan for Stereotactic Radiosurgery at Oncology Department of the General Hospital of Mexico

    SciTech Connect

    Alvarez R, J. T.; Salinas, B.; Tovar M, V. M.; Villasenor O, L. F.; Molero M, A. C.

    2006-09-08

    The verification consists on the planning and administration of stereotactic treatments by means of conformed static beams, several polyethylene capsules with powder TLD 100 (type IAEA) located inside the head of a phantom Alderson-Rando. Because the planning system corrects for no-homogeneity in the density from the tomographic information, it is assumed that the absorbed dose in the tumor volume (capsule) corresponds to the dose absorbed to LiF: DLiF. Applying different cavity theories, the percent deviations to the nominal dose are: -1.81%{<=}{delta}%{<=}0.71%, which are consistent with the order of the U%'s. The values of DW are calculated from two calibration curve: TL Response (nC) vs DW for the energy of the 60Co corrected for energy dependence to the accelerator photon beam quality D20/D10=0.57. Once curve for 0.5 to 5 Gy and other for 5 to 35 Gy. The traceability for the Dwater is obtained by means of a secondary standard ionization chamber Farmer PTW 30013 calibrated at the NRC.

  10. SU-E-T-130: Dosimetric Evaluation of Tissue Equivalent Gel Dosimeter Using Saccharide in Radiotherapy System

    SciTech Connect

    Cho, Y; Lee, D; Jung, H; Ji, Y; Kim, K; Chang, U; Kwon, S

    2014-06-01

    Purpose: In this study, the dose responses of the MAGIC gel with various concentrations and type of saccharide are examined to clarify the roles of mono and disaccharide in the polymerization process. Then we focused on the tissue equivalence and dose sensitivity of MAGIC gel dosimeters. Methods: The gel is composed of HPLC, 8% gelatin, 2 × 10-3 M L-ascorbic acid, 1.8 × 10-2 M hydroquinone, 8 × 10-5 M copper(II)sulfate and 9% methacrylic acid, new polymer gels are synthesized by adding glucose(monosaccharide), sucrose(disaccharide) and urea in the concentration range of 5∼35%. For irradiation of the gel, cesium-137 gamma-ray irradiator was used, radiation dose was delivered from 5∼50 Gy. MRI images of the gel were acquired by using a 3.0 T MRI system. Results: When saccharide and urea were added, the O/C, O/N and C/N ratios agreed with those of soft tissue with 1.7%. The dose-response of glucose and sucrose gel have slope-to-intercept ratio of 0.044 and 0.283 respectively. The slope-to-ratio is one important determinant of gel sensitivity. R-square values of glucose and sucrose gel dosimeters were 0.984 and 0.994 respectively. Moreover when urea were added, the slope-to-intercept ratio is 0.044 and 0.073 respectively. R-square values of mono and disaccharide gel were 0.973 and 0.989 respectively. When a saccharide is added into the MAGIC gel dosimeter, dose sensitivity is increased. However when urea were added, dose sensitivity is slightly decreased. Conclusion: In this study, it was possible to obtain the following conclusions by looking at the dose response characteristics after adding mono-, di-saccharide and urea to a MAGIC gel dosimeter. Saccharide was a tendency of increasing dose sensitivity with disaccharide. Sa.ccharide is cost effective, safe, soft tissue equivalent, and can be used under various experimental conditions, making it a suitable dosimeter for some radiotherapy applications.

  11. 39 CFR 761.8 - Servicing book-entry Postal Service securities; payment of interest, payment at maturity or upon...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Servicing book-entry Postal Service securities... POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS BOOK-ENTRY PROCEDURES § 761.8 Servicing book-entry Postal Service securities; payment of interest, payment at maturity or...

  12. 39 CFR 761.8 - Servicing book-entry Postal Service securities; payment of interest, payment at maturity or upon...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Servicing book-entry Postal Service securities... POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS BOOK-ENTRY PROCEDURES § 761.8 Servicing book-entry Postal Service securities; payment of interest, payment at maturity or...

  13. 39 CFR 761.8 - Servicing book-entry Postal Service securities; payment of interest, payment at maturity or upon...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Servicing book-entry Postal Service securities... POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS BOOK-ENTRY PROCEDURES § 761.8 Servicing book-entry Postal Service securities; payment of interest, payment at maturity or...

  14. 39 CFR 761.8 - Servicing book-entry Postal Service securities; payment of interest, payment at maturity or upon...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Servicing book-entry Postal Service securities... POSTAL SERVICE POSTAL SERVICE DEBT OBLIGATIONS; DISBURSEMENT POSTAL MONEY ORDERS BOOK-ENTRY PROCEDURES § 761.8 Servicing book-entry Postal Service securities; payment of interest, payment at maturity or...

  15. Dosimetric Characteristics for Brachytherapy Sources

    SciTech Connect

    DeWerd, Larry A.; Davis, Stephen D.

    2011-05-05

    Brachytherapy sources are characterized by the dosimetric parameters in a protocol such as the American Association of Physicists in Medicine Task Group 43. The air-kerma strength is measured and traceable to a primary standard. Then the parameters such as dose-rate constant, radial dose function, and anisotropy function are measured and related back to the primary standard. This is normally accomplished with thermoluminescent dosimeters (TLDs). Since radial dose function and anisotropy function are relative parameters, some of the dosimetric corrections are negligible. For the dose-rate constant, parameters such as the energy dependence compared with a calibration beam such as {sup 60}Co need to be accounted for. A description of the primary standard measurements and TLD measurements will be discussed.

  16. 77 FR 64362 - Postal Rate and Classification Changes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-19

    ... Postal Rate and Classification Changes AGENCY: Postal Regulatory Commission. ACTION: Notice. ] SUMMARY... Stamp (from 45 cents to 46 cents). The Postal Service is also planning to make mail classification... �������������������������������������������������������� Total 2.114 Id. at 6-7. Classification changes. The Adjustment Notice identifies numerous...

  17. 39 CFR 778.10 - How does the Postal Service make efforts to accommodate intergovernmental concerns?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false How does the Postal Service make efforts to... SPECIAL REGULATIONS INTERGOVERNMENTAL REVIEW OF POSTAL SERVICE FACILITY ACTIONS § 778.10 How does the Postal Service make efforts to accommodate intergovernmental concerns? (a) If a state process provides...

  18. 39 CFR 778.10 - How does the Postal Service make efforts to accommodate intergovernmental concerns?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false How does the Postal Service make efforts to... SPECIAL REGULATIONS INTERGOVERNMENTAL REVIEW OF POSTAL SERVICE FACILITY ACTIONS § 778.10 How does the Postal Service make efforts to accommodate intergovernmental concerns? (a) If a state process provides...

  19. 39 CFR 778.10 - How does the Postal Service make efforts to accommodate intergovernmental concerns?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false How does the Postal Service make efforts to... SPECIAL REGULATIONS INTERGOVERNMENTAL REVIEW OF POSTAL SERVICE FACILITY ACTIONS § 778.10 How does the Postal Service make efforts to accommodate intergovernmental concerns? (a) If a state process provides...

  20. 39 CFR 778.10 - How does the Postal Service make efforts to accommodate intergovernmental concerns?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false How does the Postal Service make efforts to... SPECIAL REGULATIONS INTERGOVERNMENTAL REVIEW OF POSTAL SERVICE FACILITY ACTIONS § 778.10 How does the Postal Service make efforts to accommodate intergovernmental concerns? (a) If a state process provides...

  1. 39 CFR 778.10 - How does the Postal Service make efforts to accommodate intergovernmental concerns?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false How does the Postal Service make efforts to... SPECIAL REGULATIONS INTERGOVERNMENTAL REVIEW OF POSTAL SERVICE FACILITY ACTIONS § 778.10 How does the Postal Service make efforts to accommodate intergovernmental concerns? (a) If a state process provides...

  2. 39 CFR 3060.43 - Annual transfer from competitive products fund to Postal Service fund.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Annual transfer from competitive products fund to Postal Service fund. 3060.43 Section 3060.43 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL ACCOUNTING PRACTICES AND TAX RULES FOR THE THEORETICAL COMPETITIVE PRODUCTS ENTERPRISE § 3060.43...

  3. 75 FR 28204 - Conduct on Postal Property; Penalties and Other Law

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-20

    ... 232 Conduct on Postal Property; Penalties and Other Law AGENCY: Postal Service. ACTION: Final rule..., Law enforcement officers, Postal Service, Security measures. 0 For the reasons stated in the preamble... violation of the rules governing conduct on Postal Service property (75 FR 4273). The former rules...

  4. 39 CFR 3055.91 - Consumer access to postal services.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... information pertaining to delivery points shall be reported, disaggregated by delivery point type, provided at... close of each successive fiscal quarter at the Postal Administrative Area and National levels....

  5. 75 FR 17789 - Nationwide Change in Frequency of Postal Delivery

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-07

    ... also describes the quantitative research it employed utilizing surveys. Id. at 12-29. The Postal... the market research activities it conducted to gauge consumer and business impact from a reduction...

  6. 39 CFR 255.8 - Access to postal facilities.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... DISABILITIES TO POSTAL SERVICE PROGRAMS, ACTIVITIES, FACILITIES, AND ELECTRONIC AND INFORMATION TECHNOLOGY... with the National Historic Preservation Act of 1966, 16 U.S.C. 470 et seq.; (vii) The availability...

  7. Reform the Postal Service for the 21st Century Act

    THOMAS, 112th Congress

    Rep. Connolly, Gerald E. [D-VA-11

    2011-03-30

    04/01/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  8. U. S. Postal Service to recycle undelivered bulk business mail

    SciTech Connect

    Not Available

    1994-09-01

    US Postal Service officials are completing a plan that they say will generate more than 500,000 tons of mixed recycled paper per year. Under a program that could begin as early as October, managers of the nation's 35,000 post offices will collect and recycle all undeliverable bulk business mail. Postal officials say recycling the flyers, magazines, and catalogs could save the federal service millions of dollars per year in transport and tipping fees.

  9. Dosimetric methodology of the ICRP

    SciTech Connect

    Eckerman, K.F.

    1994-12-31

    Establishment of guidance for the protection of workers and members of the public from radiation exposures necessitates estimation of the radiation dose to tissues of the body at risk. The dosimetric methodology formulated by the International Commission on Radiological Protection (ICRP) is intended to be responsive to this need. While developed for radiation protection, elements of the methodology are often applied in addressing other radiation issues; e.g., risk assessment. This chapter provides an overview of the methodology, discusses its recent extension to age-dependent considerations, and illustrates specific aspects of the methodology through a number of numerical examples.

  10. 77 FR 35432 - Privacy Act of 1974, Computer Matching Program: United States Postal Service and the Defense...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    .... FOR FURTHER INFORMATION CONTACT: Jane Eyre at (202) 268-2608. SUPPLEMENTARY INFORMATION: The Postal... (SOR) 100.400 as amended by 76 FR 35484 (June 17, 2011)) will be compared with a file of records of... identified as DMDC 02 DoD, ``Defense Enrollment Eligibility Reporting System (DEERS)'', as amended by 76...

  11. IPIP: A new approach to inverse planning for HDR brachytherapy by directly optimizing dosimetric indices

    SciTech Connect

    Siauw, Timmy; Cunha, Adam; Atamtuerk, Alper; Hsu, I-Chow; Pouliot, Jean; Goldberg, Ken

    2011-07-15

    Purpose: Many planning methods for high dose rate (HDR) brachytherapy require an iterative approach. A set of computational parameters are hypothesized that will give a dose plan that meets dosimetric criteria. A dose plan is computed using these parameters, and if any dosimetric criteria are not met, the process is iterated until a suitable dose plan is found. In this way, the dose distribution is controlled by abstract parameters. The purpose of this study is to develop a new approach for HDR brachytherapy by directly optimizing the dose distribution based on dosimetric criteria. Methods: The authors developed inverse planning by integer program (IPIP), an optimization model for computing HDR brachytherapy dose plans and a fast heuristic for it. They used their heuristic to compute dose plans for 20 anonymized prostate cancer image data sets from patients previously treated at their clinic database. Dosimetry was evaluated and compared to dosimetric criteria. Results: Dose plans computed from IPIP satisfied all given dosimetric criteria for the target and healthy tissue after a single iteration. The average target coverage was 95%. The average computation time for IPIP was 30.1 s on an Intel(R) Core{sup TM}2 Duo CPU 1.67 GHz processor with 3 Gib RAM. Conclusions: IPIP is an HDR brachytherapy planning system that directly incorporates dosimetric criteria. The authors have demonstrated that IPIP has clinically acceptable performance for the prostate cases and dosimetric criteria used in this study, in both dosimetry and runtime. Further study is required to determine if IPIP performs well for a more general group of patients and dosimetric criteria, including other cancer sites such as GYN.

  12. Dosimetric Predictors of Laryngeal Edema

    SciTech Connect

    Sanguineti, Giuseppe . E-mail: gisangui@utmb.edu; Adapala, Prashanth; Endres, Eugene J. C; Brack, Collin; Fiorino, Claudio; Sormani, Maria Pia; Parker, Brent

    2007-07-01

    Purpose: To investigate dosimetric predictors of laryngeal edema after radiotherapy (RT). Methods and Materials: A total of 66 patients were selected who had squamous cell carcinoma of the head and neck with grossly uninvolved larynx at the time of RT, no prior major surgical operation except for neck dissection and tonsillectomy, treatment planning data available for analysis, and at least one fiberoptic examination of the larynx within 2 years from RT performed by a single observer. Both the biologically equivalent mean dose at 2 Gy per fraction and the cumulative biologic dose-volume histogram of the larynx were extracted for each patient. Laryngeal edema was prospectively scored after treatment. Time to endpoint, moderate or worse laryngeal edema (Radiation Therapy Oncology Group Grade 2+), was calculated with log rank test from the date of treatment end. Results: At a median follow-up of 17.1 months (range, 0.4- 50.0 months), the risk of Grade 2+ edema was 58.9% {+-} 7%. Mean dose to the larynx, V30, V40, V50, V60, and V70 were significantly correlated with Grade 2+ edema at univariate analysis. At multivariate analysis, mean laryngeal dose (continuum, hazard ratio, 1.11; 95% confidence interval, 1.06-1.15; p < 0.001), and positive neck stage at RT (N0-x vs. N +, hazard ratio, 3.66; 95% confidence interval, 1.40-9.58; p = 0.008) were the only independent predictors. Further stratification showed that, to minimize the risk of Grade 2+ edema, the mean dose to the larynx has to be kept {<=}43.5 Gy at 2 Gy per fraction. Conclusion: Laryngeal edema is strictly correlated with various dosimetric parameters; mean dose to the larynx should be kept {<=}43.5 Gy.

  13. Statistical process control for IMRT dosimetric verification.

    PubMed

    Breen, Stephen L; Moseley, Douglas J; Zhang, Beibei; Sharpe, Michael B

    2008-10-01

    Patient-specific measurements are typically used to validate the dosimetry of intensity-modulated radiotherapy (IMRT). To evaluate the dosimetric performance over time of our IMRT process, we have used statistical process control (SPC) concepts to analyze the measurements from 330 head and neck (H&N) treatment plans. The objectives of the present work are to: (i) Review the dosimetric measurements of a large series of consecutive head and neck treatment plans to better understand appropriate dosimetric tolerances; (ii) analyze the results with SPC to develop action levels for measured discrepancies; (iii) develop estimates for the number of measurements that are required to describe IMRT dosimetry in the clinical setting; and (iv) evaluate with SPC a new beam model in our planning system. H&N IMRT cases were planned with the PINNACLE treatment planning system versions 6.2b or 7.6c (Philips Medical Systems, Madison, WI) and treated on Varian (Palo Alto, CA) or Elekta (Crawley, UK) linacs. As part of regular quality assurance, plans were recalculated on a 20-cm-diam cylindrical phantom, and ion chamber measurements were made in high-dose volumes (the PTV with highest dose) and in low-dose volumes (spinal cord organ-at-risk, OR). Differences between the planned and measured doses were recorded as a percentage of the planned dose. Differences were stable over time. Measurements with PINNACLE3 6.2b and Varian linacs showed a mean difference of 0.6% for PTVs (n=149, range, -4.3% to 6.6%), while OR measurements showed a larger systematic discrepancy (mean 4.5%, range -4.5% to 16.3%) that was due to well-known limitations of the MLC model in the earlier version of the planning system. Measurements with PINNACLE3 7.6c and Varian linacs demonstrated a mean difference of 0.2% for PTVs (n=160, range, -3.0%, to 5.0%) and -1.0% for ORs (range -5.8% to 4.4%). The capability index (ratio of specification range to range of the data) was 1.3 for the PTV data, indicating that almost

  14. Statistical process control for IMRT dosimetric verification

    SciTech Connect

    Breen, Stephen L.; Moseley, Douglas J.; Zhang, Beibei; Sharpe, Michael B.

    2008-10-15

    Patient-specific measurements are typically used to validate the dosimetry of intensity-modulated radiotherapy (IMRT). To evaluate the dosimetric performance over time of our IMRT process, we have used statistical process control (SPC) concepts to analyze the measurements from 330 head and neck (H and N) treatment plans. The objectives of the present work are to: (i) Review the dosimetric measurements of a large series of consecutive head and neck treatment plans to better understand appropriate dosimetric tolerances; (ii) analyze the results with SPC to develop action levels for measured discrepancies; (iii) develop estimates for the number of measurements that are required to describe IMRT dosimetry in the clinical setting; and (iv) evaluate with SPC a new beam model in our planning system. H and N IMRT cases were planned with the PINNACLE{sup 3} treatment planning system versions 6.2b or 7.6c (Philips Medical Systems, Madison, WI) and treated on Varian (Palo Alto, CA) or Elekta (Crawley, UK) linacs. As part of regular quality assurance, plans were recalculated on a 20-cm-diam cylindrical phantom, and ion chamber measurements were made in high-dose volumes (the PTV with highest dose) and in low-dose volumes (spinal cord organ-at-risk, OR). Differences between the planned and measured doses were recorded as a percentage of the planned dose. Differences were stable over time. Measurements with PINNACLE{sup 3} 6.2b and Varian linacs showed a mean difference of 0.6% for PTVs (n=149, range, -4.3% to 6.6%), while OR measurements showed a larger systematic discrepancy (mean 4.5%, range -4.5% to 16.3%) that was due to well-known limitations of the MLC model in the earlier version of the planning system. Measurements with PINNACLE{sup 3} 7.6c and Varian linacs demonstrated a mean difference of 0.2% for PTVs (n=160, range, -3.0%, to 5.0%) and -1.0% for ORs (range -5.8% to 4.4%). The capability index (ratio of specification range to range of the data) was 1.3 for the PTV

  15. Statistical process control for IMRT dosimetric verification.

    PubMed

    Breen, Stephen L; Moseley, Douglas J; Zhang, Beibei; Sharpe, Michael B

    2008-10-01

    Patient-specific measurements are typically used to validate the dosimetry of intensity-modulated radiotherapy (IMRT). To evaluate the dosimetric performance over time of our IMRT process, we have used statistical process control (SPC) concepts to analyze the measurements from 330 head and neck (H&N) treatment plans. The objectives of the present work are to: (i) Review the dosimetric measurements of a large series of consecutive head and neck treatment plans to better understand appropriate dosimetric tolerances; (ii) analyze the results with SPC to develop action levels for measured discrepancies; (iii) develop estimates for the number of measurements that are required to describe IMRT dosimetry in the clinical setting; and (iv) evaluate with SPC a new beam model in our planning system. H&N IMRT cases were planned with the PINNACLE treatment planning system versions 6.2b or 7.6c (Philips Medical Systems, Madison, WI) and treated on Varian (Palo Alto, CA) or Elekta (Crawley, UK) linacs. As part of regular quality assurance, plans were recalculated on a 20-cm-diam cylindrical phantom, and ion chamber measurements were made in high-dose volumes (the PTV with highest dose) and in low-dose volumes (spinal cord organ-at-risk, OR). Differences between the planned and measured doses were recorded as a percentage of the planned dose. Differences were stable over time. Measurements with PINNACLE3 6.2b and Varian linacs showed a mean difference of 0.6% for PTVs (n=149, range, -4.3% to 6.6%), while OR measurements showed a larger systematic discrepancy (mean 4.5%, range -4.5% to 16.3%) that was due to well-known limitations of the MLC model in the earlier version of the planning system. Measurements with PINNACLE3 7.6c and Varian linacs demonstrated a mean difference of 0.2% for PTVs (n=160, range, -3.0%, to 5.0%) and -1.0% for ORs (range -5.8% to 4.4%). The capability index (ratio of specification range to range of the data) was 1.3 for the PTV data, indicating that almost

  16. Practical simplifications for radioimmunotherapy dosimetric models

    SciTech Connect

    Shen, S.; DeNardo, G.L.; O`Donnell, R.T.; Yuan, A.; DeNardo, D.A.; Macey, D.J.; DeNardo, S.J.

    1999-01-01

    Radiation dosimetry is potentially useful for assessment and prediction of efficacy and toxicity for radionuclide therapy. The usefulness of these dose estimates relies on the establishment of a dose-response model using accurate pharmacokinetic data and a radiation dosimetric model. Due to the complexity in radiation dose estimation, many practical simplifications have been introduced in the dosimetric modeling for clinical trials of radioimmunotherapy. Although research efforts are generally needed to improve the simplifications used at each stage of model development, practical simplifications are often possible for specific applications without significant consequences to the dose-response model. In the development of dosimetric methods for radioimmunotherapy, practical simplifications in the dosimetric models were introduced. This study evaluated the magnitude of uncertainty associated with practical simplifications for: (1) organ mass of the MIRD phantom; (2) radiation contribution from target alone; (3) interpolation of S value; (4) macroscopic tumor uniformity; and (5) fit of tumor pharmacokinetic data.

  17. 76 FR 59768 - Advisory Committee on International Postal and Delivery Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Advisory Committee on International Postal and Delivery Services AGENCY: Department of State. ACTION: Notice... the meeting of the Advisory Committee on International Postal and Delivery Services scheduled...

  18. Dosimetric Effects of Setup Uncertainties on Breast Treatment Delivery

    SciTech Connect

    Harron, Elizabeth Christine McCallum, Hazel Mhairi; Lambert, Elizabeth Lyn; Lee, Daniela; Lambert, Geoffrey David

    2008-01-01

    This study aimed to assess the dosimetric impact of setup errors during the delivery of radiotherapy to the breast, and use this information to make recommendations on intervention tolerances for portal imaging of breast treatments. Translational and rotational setup errors were simulated for 10 recent breast patients using an Oncentra MasterPlan treatment planning system. The effect of these errors on the breast and tumor bed target volumes receiving 95% and 107% of the prescribed dose were assessed. For the majority of patients, shifts of up to 10 mm or a 4 deg. patient rotation about the cranio-caudal axis had no significant effect on the dose distribution. Changes in dosimetry were more likely if the reference plan contained large hot or cold spots. For a typical patient, it is estimated that a shift of 5 mm in any one direction, or a 2 deg. patient rotation would not cause more than a 5% change in the target volume receiving between 95% and 107% of the prescribed dose. If combinations of errors occur, greater dosimetric changes would be expected. It is concluded that individual patient shifts of up to 5 mm or rotations about the cranio-caudal axis of 2 deg. or less are unlikely to affect dose-volume histogram parameters by an amount judged as clinically significant. Setup errors exceeding these values may cause large dosimetric changes for some patients, particularly those with larger hot or cold regions in the dose distribution, and intervention is therefore recommended.

  19. Proton Radiotherapy for Liver Tumors: Dosimetric Advantages Over Photon Plans

    SciTech Connect

    Wang Xiaochun Krishnan, Sunil; Zhang Xiaodong; Dong Lei; Briere, Tina; Crane, Christopher H.; Martel, Mary; Gillin, Michael; Mohan, Radhe; Beddar, Sam

    2008-01-01

    The purpose of the study is to dosimetrically investigate the advantages of proton radiotherapy over photon radiotherapy for liver tumors. The proton plan and the photon plan were designed using commercial treatment planning systems. The treatment target dose conformity and heterogeneity and dose-volume analyses of normal structures were compared between proton and photon radiotherapy for 9 patients with liver tumors. Proton radiotherapy delivered a more conformal target dose with slightly less homogeneity when compared with photon radiotherapy. Protons significantly reduced the fractional volume of liver receiving dose greater or equal to 30 Gy (V{sub 30}) and the mean liver dose. The stomach and duodenal V{sub 45} were significantly lower with the use of proton radiotherapy. The V{sub 40} and V{sub 50} of the heart and the maximum spinal cord dose were also significantly lower with the use of proton radiotherapy. Protons were better able to spare one kidney completely and deliver less dose to one (generally the left) kidney than photons. The mean dose to the total body and most critical structures was significantly decreased using protons when compared to corresponding photon plans. In conclusion, our study suggests the dosimetric benefits of proton radiotherapy over photon radiotherapy. These dosimetric advantages of proton plans may permit further dose escalation with lower risk of complications.

  20. Typing Postal Cards. Student's Manual and Instructor's Manual.

    ERIC Educational Resources Information Center

    Snapp, Jane

    Supporting performance objective 85 of the V-TECS (Vocational-Technical Education Consortium of States) Secretarial Catalog, both a set of student materials and an instructor's manual on typing postal cards are included in this packet. (The packet is the seventh in a set of fifteen on typewriting--CE 016 920-934.) The student materials include a…

  1. 75 FR 10843 - Special Summer Postal Rate Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-09

    ... 3010.\\1\\ The proposed adjustment is another Standard Mail Volume Incentive Pricing Program (Standard... Commission.\\3\\ The planned implementation date of the Standard Mail Incentive Program is July 1, 2010, and the planned expiration date is September 30, 2010. \\1\\ United States Postal Service Notice of...

  2. 76 FR 53982 - New Postal Product and Rate Adjustment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-30

    ...). In Order No. 700, the Commission approved the functionally equivalent HongKong Post Agreement.\\2\\ The..., TNT Agreement, and the HongKong Post Agreement. The Postal Service requests that the China Post 2011... Operators 1 product. Notice at 2. \\2\\ See Docket No. R2011-4, Order Approving Rate Adjustment for...

  3. 76 FR 51311 - Administrative Practice and Procedure, Postal Service

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-18

    ... Postal Service's product structure has developed under the PAEA. This task is incorporated into the...). SUPPLEMENTARY HISTORY: Regulatory History: 72 FR 29284, May 25, 2007; 72 FR 33261, June 15, 2007; 72 FR 50744... (Order No. 45); see also 72 FR 63662 (November 9, 2007). The publication of the initial product...

  4. 77 FR 63898 - New Postal Product; Negotiated Service Agreement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-17

    ... Mail Contract 11 to the competitive product list. This notice addresses procedural steps associated... competitive product list.\\1\\ The Postal Service asserts that Express Mail & Priority Mail Contract 11 is a... Add Express Mail & Priority Mail Contract 11 to Competitive Product List and Notice of Filing...

  5. 39 CFR 232.1 - Conduct on postal property.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... authorized by state law. (g) Alcoholic beverages, drugs, and smoking. (1) A person under the influence of an... substance” is defined in section 802 of title 21 U.S.C. (2) Smoking (defined as having a lighted cigar, cigarette, pipe, or other smoking material) is prohibited in all postal buildings and office...

  6. 75 FR 4273 - Conduct on Postal Property; Penalties and Other Law

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-27

    ... 232 Conduct on Postal Property; Penalties and Other Law AGENCY: Postal Service. ACTION: Final rule... penalty for violations of the rules concerning conduct on Postal Service property. The authorized maximum... Service property establish the maximum penalty for a violation as a fine of not more than $50...

  7. 76 FR 15028 - Advisory Committee on International Postal and Delivery Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-18

    ... Committee on International Postal and Delivery Services AGENCY: Department of State. ACTION: Notice; FACA... Postal and Delivery Services. This Committee has been formed in fulfillment of the provisions of the 2006... related to international postal and delivery services of interest to Advisory Committee members and...

  8. 77 FR 2340 - Advisory Committee on International Postal and Delivery Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... Committee on International Postal and Delivery Services AGENCY: Department of State. ACTION: Notice of... the renewal of the charter of the Advisory Committee on International Postal and Delivery Services in... oversight of foreign policy related to international postal services and other international...

  9. 75 FR 57102 - Advisory Committee on International Postal and Delivery Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ... Committee on International Postal and Delivery Services AGENCY: Department of State. ACTION: Notice; FACA... Postal and Delivery Services. This Committee has been formed in fulfillment of the provisions of the 2006... related to international postal and delivery services of interest to Advisory Committee members and...

  10. 77 FR 65231 - New Postal Product and Related Negotiated Service Agreement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-25

    ... Request. Id. Attachment B. The contract is scheduled to become effective on the first business day after... New Postal Product and Related Negotiated Service Agreement AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to...

  11. 77 FR 65232 - New Postal Product and Related Negotiated Service Agreement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-25

    ... the Request. Id. Attachment B. The contract is scheduled to become effective on the day after the date... New Postal Product and Related Negotiated Service Agreement AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to...

  12. 77 FR 65024 - New Postal Product and Related Negotiated Service Agreement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-24

    ... become effective on the first business day after the date that the Commission issues all regulatory... New Postal Product and Related Negotiated Service Agreement AGENCY: Postal Regulatory Commission. ACTION: Notice. SUMMARY: The Commission is noticing a recently-filed Postal Service request to...

  13. Dosimetric monitoring in Ukraine--present status and path to the future.

    PubMed

    Chumak, V; Boguslavskaya, A

    2007-01-01

    Despite wide use of nuclear energy and radiation sources in industry and medicine, there is no centralised dose accounting system in Ukraine; existing dosimetry services operate obsolete manual thermoluminescence dosemeter (TLD) readers and do not meet modern proficiency standards. Currently, dosimetric monitoring is required for approximately 42,000 occupationally exposed workers, including 9100 in medicine, 17,000 employees of nuclear power plants and approximately 16,000 workers dealing with other sources of occupational exposure. This article presents the plan of elaboration of the United System for monitoring and registration of individual doses which has the aim of harmonisation of individual monitoring in Ukraine through securing methodical unity; scientific and methodological guidance of individual dosimetric control; procurement of common technical policy regarding nomenclature and operation of instrumentation; implementation of quality assurance programmes; development and support of information infrastructure, in particular operation of the national registry of individual doses; training and certification of personnel engaged in the system of individual dosimetric monitoring.

  14. 39 CFR 778.8 - How does the Postal Service provide states an opportunity to comment on proposed facility project...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false How does the Postal Service provide states an opportunity to comment on proposed facility project actions? 778.8 Section 778.8 Postal Service UNITED STATES... How does the Postal Service provide states an opportunity to comment on proposed facility...

  15. 39 CFR 778.8 - How does the Postal Service provide states an opportunity to comment on proposed facility project...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false How does the Postal Service provide states an opportunity to comment on proposed facility project actions? 778.8 Section 778.8 Postal Service UNITED STATES... How does the Postal Service provide states an opportunity to comment on proposed facility...

  16. 39 CFR 778.8 - How does the Postal Service provide states an opportunity to comment on proposed facility project...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false How does the Postal Service provide states an opportunity to comment on proposed facility project actions? 778.8 Section 778.8 Postal Service UNITED STATES... How does the Postal Service provide states an opportunity to comment on proposed facility...

  17. 39 CFR 778.8 - How does the Postal Service provide states an opportunity to comment on proposed facility project...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false How does the Postal Service provide states an opportunity to comment on proposed facility project actions? 778.8 Section 778.8 Postal Service UNITED STATES... How does the Postal Service provide states an opportunity to comment on proposed facility...

  18. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  19. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  20. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  1. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  2. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  3. The U.S. Postal Service: Delivering the recycling message

    SciTech Connect

    O`Connell, K.A.

    1998-07-01

    As federal agencies struggle to comply with government directives on recycling, the US Postal Service (USPS) has jumped ahead of its governmental peers, taking a leadership stance on recycling and waste diversion and unveiling several new programs and initiatives. In late April, the agency held its third annual Environmental Stakeholders Conference, with a theme of Sustainable Development in Postal Business. The conference focused on several environmental initiatives under way in the agency. It is noted that the agency has purchased $160 million in products made with recycled content. The agency took in $1.4 million in revenue from recycling in 1993. Last year, the agency took in $8 million in recycling revenue. Other environmental programs are standouts as well. The agency has the single largest fleet of alternative fuel vehicles in the nation. It has transformed undeliverable mail into compost and pencils and even lobby recycling bins.

  4. Dosimetric effects of patient rotational setup errors on prostate IMRT treatments

    NASA Astrophysics Data System (ADS)

    Fu, Weihua; Yang, Yong; Li, Xiang; Heron, Dwight E.; Saiful Huq, M.; Yue, Ning J.

    2006-10-01

    The purpose of this work is to determine dose delivery errors that could result from systematic rotational setup errors (ΔΦ) for prostate cancer patients treated with three-phase sequential boost IMRT. In order to implement this, different rotational setup errors around three Cartesian axes were simulated for five prostate patients and dosimetric indices, such as dose-volume histogram (DVH), tumour control probability (TCP), normal tissue complication probability (NTCP) and equivalent uniform dose (EUD), were employed to evaluate the corresponding dosimetric influences. Rotational setup errors were simulated by adjusting the gantry, collimator and horizontal couch angles of treatment beams and the dosimetric effects were evaluated by recomputing the dose distributions in the treatment planning system. Our results indicated that, for prostate cancer treatment with the three-phase sequential boost IMRT technique, the rotational setup errors do not have significant dosimetric impacts on the cumulative plan. Even in the worst-case scenario with ΔΦ = 3°, the prostate EUD varied within 1.5% and TCP decreased about 1%. For seminal vesicle, slightly larger influences were observed. However, EUD and TCP changes were still within 2%. The influence on sensitive structures, such as rectum and bladder, is also negligible. This study demonstrates that the rotational setup error degrades the dosimetric coverage of target volume in prostate cancer treatment to a certain degree. However, the degradation was not significant for the three-phase sequential boost prostate IMRT technique and for the margin sizes used in our institution.

  5. Comparing the dosimetric characteristics of the electron beam from dedicated intraoperative and conventional radiotherapy accelerators.

    PubMed

    Baghani, Hamid Reza; Aghamiri, Seyed Mahmoud Reza; Mahdavi, Seyed Rabi; Akbari, Mohammad Esmail; Mirzaei, Hamid Reza

    2015-01-01

    The specific design of the mobile dedicated intraoperative radiotherapy (IORT) accelerators and different electron beam collimation system can change the dosimetric characteristics of electron beam with respect to the conventional accelerators. The aim of this study is to measure and compare the dosimetric characteristics of electron beam produced by intraoperative and conventional radiotherapy accelerators. To this end, percentage depth dose along clinical axis (PDD), transverse dose profile (TDP), and output factor of LIAC IORT and Varian 2100C/D conventional radiotherapy accelerators were measured and compared. TDPs were recorded at depth of maximum dose. The results of this work showed that depths of maximum dose, R90, R50, and RP for LIAC beam are lower than those of Varian beam. Furthermore, for all energies, surface doses related to the LIAC beam are substantially higher than those of Varian beam. The symmetry and flatness of LIAC beam profiles are more desirable compared to the Varian ones. Contrary to Varian accelerator, output factor of LIAC beam substantially increases with a decrease in the size of the applicator. Dosimetric characteristics of beveled IORT applicators along clinical axis were different from those of the flat ones. From these results, it can be concluded that dosimetric characteristics of intraoperative electron beam are substantially different from those of conventional clinical electron beam. The dosimetric characteristics of the LIAC electron beam make it a useful tool for intraoperative radiotherapy purposes.

  6. Transport and dosimetric solutions for the ELIMED laser-driven beam line

    NASA Astrophysics Data System (ADS)

    Cirrone, G. A. P.; Romano, F.; Scuderi, V.; Amato, A.; Candiano, G.; Cuttone, G.; Giove, D.; Korn, G.; Krasa, J.; Leanza, R.; Manna, R.; Maggiore, M.; Marchese, V.; Margarone, D.; Milluzzo, G.; Petringa, G.; Sabini, M. G.; Schillaci, F.; Tramontana, A.; Valastro, L.; Velyhan, A.

    2015-10-01

    Within 2017, the ELIMED (ELI-Beamlines MEDical applications) transport beam-line and dosimetric systems for laser-generated beams will be installed at the ELI-Beamlines facility in Prague (CZ), inside the ELIMAIA (ELI Multidisciplinary Applications of laser-Ion Acceleration) interaction room. The beam-line will be composed of two sections: one in vacuum, devoted to the collecting, focusing and energy selection of the primary beam and the second in air, where the ELIMED beam-line dosimetric devices will be located. This paper briefly describes the transport solutions that will be adopted together with the main dosimetric approaches. In particular, the description of an innovative Faraday Cup detector with its preliminary experimental tests will be reported.

  7. 78 FR 43245 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... electronically via the Commission's Filing Online system at http://www.prc.gov . Those who cannot submit comments... accessed via the Commission's Web site ( http://www.prc.gov ). The Commission appoints Curtis E. Kidd to.... Pursuant to 39 U.S.C. 505, Curtis E. Kidd is appointed to serve as an officer of the Commission...

  8. 78 FR 79025 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... electronically via the Commission's Filing Online system at http://www.prc.gov . Those who cannot submit comments... ( http://www.prc.gov ). The Commission appoints Curtis E. Kidd to serve as Public Representative in these... E. Kidd is appointed to serve as an officer of the Commission to represent the interests of...

  9. 76 FR 52718 - Complaint About Postal Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-23

    ... Online system at https://www.prc.gov/prc-pages/filing-online/login.aspx . Commenters who cannot submit... impetus for the Complaint stems from three developments that span more than 5 years. The first was a... of settlement within 30 days of the issuance of this order. V. Ordering Paragraphs It is ordered:...

  10. CURRENT STATUS OF INDIVIDUAL DOSIMETRIC MONITORING IN UKRAINE.

    PubMed

    Chumak, V; Deniachenko, N; Makarovska, O; Mihailescu, L-C; Prykhodko, A; Voloskyi, V; Vanhavere, F

    2016-09-01

    About 50 000 workers are being occupationally exposed to radiation in Ukraine. Individual dosimetric monitoring (IDM) is provided by 77 dosimetry services and laboratories of very different scale with a number of monitored workers ranging from several persons to ∼9000. In the present work, the current status of personal dosimetry in Ukraine was studied. The First National Intercomparison (FNI) of the IDM labs was accompanied by a survey of the laboratory operation in terms of coverage, types of dosimetry provided, instrumentation and methodologies used, metrological support, data recording, etc. Totally, 34 laboratories responded to the FNI call, and 18 services with 19 different personal dosimetry systems took part in the intercomparison exercise providing 24 dosimeters each for blind irradiation to photons of 6 different qualities (ISO N-series X-rays, S-Cs and S-Co sources) in a dose range of 5-60 mSv. Performance of the dosimetry labs was evaluated according to ISO 14146 criteria of matching trumpet curves with H0 = 0.2 mSv. The test revealed that 8 of the 19 systems meet ISO 14146 criteria in full, 5 other labs show marginal performance and 6 laboratories demonstrated catastrophic quality of dosimetric results. Altogether, 18 participating labs provide dosimetric monitoring to 37 477 workers (about three-fourths of all occupationally exposed workers), usually on monthly (nuclear industry) or quarterly (rest of applications) basis. Of this number, 20 664 persons (55 %) receive completely adequate individual monitoring, and the number of personnel receiving IDM of inadequate quality counts 3054 persons. PMID:26979804

  11. Increasing response rates to postal questionnaires: systematic review

    PubMed Central

    Edwards, Phil; Roberts, Ian; Clarke, Mike; DiGuiseppi, Carolyn; Pratap, Sarah; Wentz, Reinhard; Kwan, Irene

    2002-01-01

    Objective To identify methods to increase response to postal questionnaires. Design Systematic review of randomised controlled trials of any method to influence response to postal questionnaires. Studies reviewed 292 randomised controlled trials including 258 315 participants Intervention reviewed 75 strategies for influencing response to postal questionnaires. Main outcome measure The proportion of completed or partially completed questionnaires returned. Results The odds of response were more than doubled when a monetary incentive was used (odds ratio 2.02; 95% confidence interval 1.79 to 2.27) and almost doubled when incentives were not conditional on response (1.71; 1.29 to 2.26). Response was more likely when short questionnaires were used (1.86; 1.55 to 2.24). Personalised questionnaires and letters increased response (1.16; 1.06 to 1.28), as did the use of coloured ink (1.39; 1.16 to 1.67). The odds of response were more than doubled when the questionnaires were sent by recorded delivery (2.21; 1.51 to 3.25) and increased when stamped return envelopes were used (1.26; 1.13 to 1.41) and questionnaires were sent by first class post (1.12; 1.02 to 1.23). Contacting participants before sending questionnaires increased response (1.54; 1.24 to 1.92), as did follow up contact (1.44; 1.22 to 1.70) and providing non-respondents with a second copy of the questionnaire (1.41; 1.02 to 1.94). Questionnaires designed to be of more interest to participants were more likely to be returned (2.44; 1.99 to 3.01), but questionnaires containing questions of a sensitive nature were less likely to be returned (0.92; 0.87 to 0.98). Questionnaires originating from universities were more likely to be returned than were questionnaires from other sources, such as commercial organisations (1.31; 1.11 to 1.54). Conclusions Health researchers using postal questionnaires can improve the quality of their research by using the strategies shown to be effective in this systematic review

  12. Patient doses and dosimetric evaluations in interventional cardiology.

    PubMed

    Bor, Dogan; Olğar, Turan; Toklu, Türkay; Cağlan, Ayça; Onal, Elif; Padovani, Renato

    2009-03-01

    Interventional cardiological examinations may be associated with excessive radiation exposures which may cause skin injuries and higher probabilities of stochastic effects. Dose-area product (DAP) and skin doses of 325 patients were measured using alternative dosimetric techniques for different cardiological examinations. Data were collected from five different systems with the involvement of 11 cardiologists. All these dosimetric information has been collected separately for each of 10 projections together with the exposure parameters of X-ray systems. Mean DAP values measured with a transparent ion chamber were 49.1 Gy cm(2), 66.8 Gy cm(2), 106.9 Gy cm(2) and 124.7 Gy cm(2), respectively, for coronary angiography (CA), percutaneous transluminal coronary angioplasty (PTCA) or stent (PT-SI), coronary angiography and/or PTCA and/or stent (CA-PT-SI), and ablation examinations. Radiochromic films, thermoluminescent dosimeters (TLD) and point measurement of air kerma (AK) were carried out for skin dose assessments. Skin doses of 23 patients measured with radiochromic films were found to be between 2 Gy and 6 Gy. Although the complexity of the procedures was the major reason for these excessive doses, considerable contributions of high X-ray output of some fluoroscopy units were also noticed. In addition to the direct measurement of DAP, alternative DAP values were also determined from the skin dose measurement techniques; exposed areas were summed on digitized radiochromic films in one technique, The product of AK reading with X-ray field size measured at the patient entrance using slow X-ray films was taken as another DAP. Good correlations were found among the DAP results and also between the entrance skin doses calculated from AK measurements and direct DAP readings (R(2)=0.91). A trigger DAP value of 130 Gy cm(2) for the 2 Gy of skin doses was derived from this relationship. Collection of dosimetric data for each projection was also investigated regarding a

  13. [Work-related disability among postal employees: incidence, duration, and social security costs in 2008].

    PubMed

    Mascarenhas, Flávia Alves Neves; Barbosa-Branco, Anadergh

    2014-06-01

    This study analyzed the characteristics of Brazilian postal workers that received sick leave benefits in 2008. The databases were from the Unified Benefits System (SUB) and the National Registry of Social Information (CNIS). The incidence rate was 556.5 benefits per 10,000 employees, and the leading causes of work-related sick leave were injuries, musculoskeletal disorders, and mental disorders. Areas most frequently reported in injuries were knees and legs, wrists and hands, ankles and feet, and shoulders and arms, with higher incidence rates in men. Women were more affected by musculoskeletal disorders and mental disorders. Average sick leave lasted longer in men, and the incidence of benefits increased with age. The States with the highest incidence rates were Mato Grosso do Sul, Goiás, and Santa Catarina, and security benefits averaged BRL 1,847.00. Postal work may involve additional risk of injuries to the limbs, due to the long distances carrying heavy weight, assault, and dog bites.

  14. 39 CFR 501.2 - Postage Evidencing System provider authorization.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... registration with the Postal Service of customers of a Postage Evidencing System. (c) Any person or entity... System, and a determination that disclosure to the applicant of Postal Service customer, financial, or... 39 Postal Service 1 2010-07-01 2010-07-01 false Postage Evidencing System provider...

  15. Comparison of Dosimetric Performance among Commercial Quality Assurance Systems for Verifying Pretreatment Plans of Stereotactic Body Radiotherapy Using Flattening-Filter-Free Beams

    PubMed Central

    2016-01-01

    The purpose of this study was to compare the performance of different commercial quality assurance (QA) systems for the pretreatment verification plan of stereotactic body radiotherapy (SBRT) with volumetric arc therapy (VMAT) technique using a flattening-filter-free beam. The verification for 20 pretreatment cancer patients (seven lung, six spine, and seven prostate cancers) were tested using three QA systems (EBT3 film, I’mRT MatriXX array, and MapCHECK). All the SBRT-VMAT plans were optimized in the Eclipse (version 11.0.34) treatment planning system (TPS) using the Acuros XB dose calculation algorithm and were delivered to the Varian TrueBeam® accelerator equipped with a high-definition multileaf collimator. Gamma agreement evaluation was analyzed with the criteria of 2% dose difference and 2 mm distance to agreement (2%/2 mm) or 3%/3 mm. The highest passing rate (99.1% for 3%/3 mm) was observed on the MapCHECK system while the lowest passing rate was obtained on the film. The pretreatment verification results depend on the QA systems, treatment sites, and delivery beam energies. However, the delivery QA results for all QA systems based on the TPS calculation showed a good agreement of more than 90% for both the criteria. It is concluded that the three 2D QA systems have sufficient potential for pretreatment verification of the SBRT-VMAT plan. PMID:27709851

  16. Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation

    NASA Astrophysics Data System (ADS)

    Magro, G.; Molinelli, S.; Mairani, A.; Mirandola, A.; Panizza, D.; Russo, S.; Ferrari, A.; Valvo, F.; Fossati, P.; Ciocca, M.

    2015-09-01

    This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5-30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo® TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus® chamber. An EBT3® film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size ratio. The accuracy of the TPS was proved to be clinically acceptable in all cases but very small and shallow volumes. In this contest, the use of MC to validate TPS results proved to be a reliable procedure for pre-treatment plan verification.

  17. Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation.

    PubMed

    Magro, G; Molinelli, S; Mairani, A; Mirandola, A; Panizza, D; Russo, S; Ferrari, A; Valvo, F; Fossati, P; Ciocca, M

    2015-09-01

    This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5-30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo(®) TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus(®) chamber. An EBT3(®) film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size ratio. The accuracy of the TPS was proved to be clinically acceptable in all cases but very small and shallow volumes. In this contest, the use of MC to validate TPS results proved to be a reliable procedure for pre-treatment plan verification.

  18. POLLUTION PREVENTION OPPORTUNITY ASSESSMENT - U.S. POSTAL SERVICE OPERATIONS, MERRIFIELD, VIRGINIA

    EPA Science Inventory

    The United States Postal Service (USPS) in cooperation with EPA’s National Risk Management Research Laboratory (NRMRL) is engaged in an effort to integrate waste prevention and recycling activities into the waste management programs at Postal facilities. This report describ...

  19. 78 FR 55773 - Advisory Committee on International Postal and Delivery Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-11

    ... Committee on International Postal and Delivery Services AGENCY: Department of State. ACTION: Notice; FACA... Postal and Delivery Services. This Committee has been formed in fulfillment of the provisions of the 2006... delivery services of interest to Advisory Committee members and the public. FOR FURTHER INFORMATION...

  20. 76 FR 54829 - Advisory Committee On International Postal and Delivery Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ...As required by the Federal Advisory Committee Act, Public Law 92-463, the Department of State gives notice of a meeting of the Advisory Committee on International Postal and Delivery Services. This Committee has been formed in fulfillment of the provisions of the 2006 Postal Accountability and Enhancement Act (Pub. L. 109-435) and in accordance with the Federal Advisory Committee...

  1. POLLUTION PREVENTION OPPORTUNITY ASSESSMENT - U.S. POSTAL SERVICE BULK MAIL CENTER, DALLAS, TEXAS

    EPA Science Inventory

    The United States Postal Service (USPS) in cooperation with EPA’s National Risk Management Research Laboratory (NRMRL) is engaged in an effort to integrate waste prevention and recycling activities into the waste management programs at Postal facilities. This report describ...

  2. 77 FR 12724 - International Postal Service-Global Expedited Package Services (GEPS) Contracts

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ... Part 20 International Postal Service--Global Expedited Package Services (GEPS) Contracts AGENCY: Postal... requirements that a mailer must meet in order to qualify for a Global Expedited Package Services (GEPS... change for the international competitive product Global Expedited Package Services (GEPS) Contracts....

  3. 39 CFR 777.33 - Expenses incidental to transfer of title to the Postal Service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... after the Postal Service obtains title to the property or effective possession of it, whichever is... RELOCATION ASSISTANCE AND REAL PROPERTY ACQUISITION POLICIES Acquisition § 777.33 Expenses incidental to transfer of title to the Postal Service. (a) Reimbursement. When property is acquired through the...

  4. 40 CFR 52.351 - United States Postal Service substitute Clean Fuel Fleet Program.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false United States Postal Service substitute Clean Fuel Fleet Program. 52.351 Section 52.351 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.351 United States Postal Service substitute Clean Fuel Fleet Program. Revisions to the...

  5. POLLUTION PREVENTION OPPORTUNITY ASSESSMENT - U.S. POSTAL SERVICE STAMP DISTRIBUTION NETWORK, KANSAS CITY, MISSOURI

    EPA Science Inventory

    The United States Postal Service (USPS) in cooperation with EPA's National Risk Management Research Laboratory (NRMRL) is engaged in an effort to integrate Waste prevention and recycling activities into the waste management programs at Postal facilities. In this report, the findi...

  6. POLLUTION PREVENTION OPPORTUNITY ASSESSMENT - U.S. POSTAL SERVICE MATERIALS DISTRIBUTION CENTER, TOPEKA, KANSAS

    EPA Science Inventory

    The United States Postal Service (USPS) in cooperation with EPA's National Risk Management Research Laboratory (NRMRL) is engaged in an effort to integrate Waste prevention and recycling activities into the waste management programs at Postal facilities. In this report, the findi...

  7. POLLUTION PREVENTION OPPORTUNITY ASSESSMENT - U.S. POSTAL INSPECTION SERVICE FORENSIC & TECHNICAL SERVICES DIVISION - NATIONAL FORENSIC LABORATORY, DULLES, VIRGINIA

    EPA Science Inventory

    The United States Postal Service (USPS) in cooperation with EPA's National Risk Management Research Laboratory (NRMRL) is engaged in an effort to integrate waste prevention and recycling activities into the waste management programs at Postal facilities. This report describes the...

  8. Dosimetric effects of a high-density spinal implant

    NASA Astrophysics Data System (ADS)

    Kairn, T.; Crowe, S. B.; Kenny, J.; Mitchell, J.; Burke, M.; Schlect, D.; Trapp, J. V.

    2013-06-01

    In this study, a treatment plan for a spinal lesion, with all beams transmitted though a titanium vertebral reconstruction implant, was used to investigate the potential effect of a high-density implant on a three-dimensional dose distribution for a radiotherapy treatment. The BEAMnrc/DOSXYZnrc and MCDTK Monte Carlo codes were used to simulate the treatment using both a simplified, recltilinear model and a detailed model incorporating the full complexity of the patient anatomy and treatment plan. The resulting Monte Carlo dose distributions showed that the commercial treatment planning system failed to accurately predict both the depletion of dose downstream of the implant and the increase in scattered dose adjacent to the implant. Overall, the dosimetric effect of the implant was underestimated by the commercial treatment planning system and overestimated by the simplified Monte Carlo model. The value of performing detailed Monte Carlo calculations, using the full patient and treatment geometry, was demonstrated.

  9. 39 CFR 3050.11 - Proposals to change an accepted analytical principle applied in the Postal Service's annual...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Proposals to change an accepted analytical... Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.11 Proposals to change an... issue a notice of proceeding to change an accepted analytical principle. In addition, any...

  10. 39 CFR 3050.11 - Proposals to change an accepted analytical principle applied in the Postal Service's annual...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Proposals to change an accepted analytical... Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.11 Proposals to change an... issue a notice of proceeding to change an accepted analytical principle. In addition, any...

  11. 39 CFR 3050.11 - Proposals to change an accepted analytical principle applied in the Postal Service's annual...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Proposals to change an accepted analytical... Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.11 Proposals to change an... issue a notice of proceeding to change an accepted analytical principle. In addition, any...

  12. 39 CFR Appendix A to Part 3002 - Postal Regulatory Commission, Mission Statement of the Office of the Consumer Advocate

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the Office of the Consumer Advocate A Appendix A to Part 3002 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL ORGANIZATION Pt. 3002, App. A Appendix A to Part 3002—Postal Regulatory Commission... Advocate is to be a vigorous, responsive, and effective advocate for reasonable and equitable treatment...

  13. 39 CFR 3050.10 - Analytical principles to be applied in the Postal Service's annual periodic reports to the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Analytical principles to be applied in the Postal... REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.10 Analytical principles to be applied in the... Commission, the Postal Service shall use only accepted analytical principles. With respect to its...

  14. 39 CFR 3055.4 - Internal measurement systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Internal measurement systems. 3055.4 Section 3055.4 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Annual Reporting of Service Performance Achievements § 3055.4 Internal...

  15. Evaluation of the applicability of pinpoint ion chambers for SRS dosimetric quality assurance

    NASA Astrophysics Data System (ADS)

    Baek, Jong Geun; Jang, Hyun Soo; Kim, Eng Chan; Lee, Yong Hee; Oh, Young Kee; Kim, Sung Kyu

    2015-06-01

    The aim of the present study was to evaluate the applicability of a Pinpoint ion chamber for the measurement of the absolute dose for dosimetric quality assurance (QA) under the same conditions as are used for actual stereotactic radiosurgery (SRS). A PTW 31014 Pinpoint chamber with a active volume of 0.015 cm3 was used to measure the absolute doses of small beams. The PTW 60003 natural diamond detector was used as a reference dosimeter. A custom-made cylindrical acrylic phantom (15 cm diameter, 15 cm long) was produced to obtain measurements, and a noncoplanar arc plan was devised to deliver a prescription dose (15-25 Gy) to 80% of the maximum dose to the target in a single fraction by using the BrainLAB planning system. All irradiations were performed by using a Varian Clinac IX 6 MV equipped with a micro-multileaf-collimators (m3) designed by BrainLAB. The acceptability criterion used was a dose difference of less than 3%. The diameter of the target volume was considered the standard parameter in the present study and was used to divide the cases into two groups, that is, a ≤ 10 mm target diameter group (10 cases) and a > 10 mm target diameter group (13 cases). For the Pinpoint chamber and target diameters of ≤ 10 mm, dosimetric uncertainties of > 3% were seen in 4 of the 10 cases, and differences ranged widely from 0.7% to 4.85%. On the other hand, for the Pinpoint chamber and target diameters of > 10 mm all dose differences were less than 1.6%, and the mean discrepancy was 0.81%. A highly significant, but moderate, correlation between dosimetric uncertainties and all target diameters was observed for the Pinpoint chamber (R2 = 0.483, p 0.001). This result indicates that Pinpoint chambers exhibit a field-size dependency when used for SRS dosimetric QA. Based on the results of the present study, we conclude that the use of a Pinpoint chamber for verification of SRS dosimetric QA is unsuitable for all field sizes, but that it can be used to verify the

  16. Dosimetric adaptive IMRT driven by fiducial points

    SciTech Connect

    Crijns, Wouter; Van Herck, Hans; Defraene, Gilles; Van den Bergh, Laura; Haustermans, Karin; Slagmolen, Pieter; Maes, Frederik; Van den Heuvel, Frank

    2014-06-15

    Purpose: Intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy have become standard treatments but are more sensitive to anatomical variations than 3D conformal techniques. To correct for inter- and intrafraction anatomical variations, fast and easy to implement methods are needed. Here, the authors propose a full dosimetric IMRT correction that finds a compromise in-between basic repositioning (the current clinical practice) and full replanning. It simplifies replanning by avoiding a recontouring step and a full dose calculation. It surpasses repositioning by updating the preoptimized fluence and monitor units (MU) using a limited number of fiducial points and a pretreatment (CB)CT. To adapt the fluence the fiducial points were projected in the beam's eye view (BEV). To adapt the MUs, point dose calculation towards the same fiducial points were performed. The proposed method is intrinsically fast and robust, and simple to understand for operators, because of the use of only four fiducial points and the beam data based point dose calculations. Methods: To perform our dosimetric adaptation, two fluence corrections in the BEV are combined with two MU correction steps along the beam's path. (1) A transformation of the fluence map such that it is realigned with the current target geometry. (2) A correction for an unintended scaling of the penumbra margin when the treatment beams scale to the current target size. (3) A correction for the target depth relative to the body contour and (4) a correction for the target distance to the source. The impact of the correction strategy and its individual components was evaluated by simulations on a virtual prostate phantom. This heterogeneous reference phantom was systematically subjected to population based prostate transformations to simulate interfraction variations. Additionally, a patient example illustrated the clinical practice. The correction strategy was evaluated using both dosimetric (CTV mean

  17. 77 FR 41877 - Advisory Committee on International Postal and Delivery Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-16

    ... accordance with the Federal Advisory Committee Act. Date and Time: The meeting will be held on Thursday... discuss the U.S. government's participation for the 25th Congress of the Universal Postal Union which...

  18. United States Postal Service Pension Obligation Recalculation and Restoration Act of 2011

    THOMAS, 112th Congress

    Rep. Lynch, Stephen F. [D-MA-9

    2011-04-04

    04/08/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  19. United States Postal Service Pension Obligation Recalculation and Restoration Act of 2011

    THOMAS, 112th Congress

    Rep. Thompson, Bennie G. [D-MS-2

    2011-10-12

    11/02/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  20. 40 CFR 52.351 - United States Postal Service substitute Clean Fuel Fleet Program.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... State Implementation Plan, carbon monoxide NAAQS, United States Postal Service substitute clean-fuel... of section 246 of the Clean Air Act for the Denver Metropolitan carbon monoxide nonattainment...

  1. 40 CFR 52.351 - United States Postal Service substitute Clean Fuel Fleet Program.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... State Implementation Plan, carbon monoxide NAAQS, United States Postal Service substitute clean-fuel... of section 246 of the Clean Air Act for the Denver Metropolitan carbon monoxide nonattainment...

  2. 40 CFR 52.351 - United States Postal Service substitute Clean Fuel Fleet Program.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... State Implementation Plan, carbon monoxide NAAQS, United States Postal Service substitute clean-fuel... of section 246 of the Clean Air Act for the Denver Metropolitan carbon monoxide nonattainment...

  3. 40 CFR 52.351 - United States Postal Service substitute Clean Fuel Fleet Program.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... State Implementation Plan, carbon monoxide NAAQS, United States Postal Service substitute clean-fuel... of section 246 of the Clean Air Act for the Denver Metropolitan carbon monoxide nonattainment...

  4. 39 CFR 501.8 - Postage Evidencing System test and approval.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Service Web site at http://www.usps.com/postagesolutions/programdoc.html or requests for copies may be... 39 Postal Service 1 2010-07-01 2010-07-01 false Postage Evidencing System test and approval. 501.8 Section 501.8 Postal Service UNITED STATES POSTAL SERVICE POSTAGE PROGRAMS AUTHORIZATION TO...

  5. 39 CFR 3055.5 - Changes to measurement systems, service standards, service goals, or reporting methodologies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Changes to measurement systems, service standards, service goals, or reporting methodologies. 3055.5 Section 3055.5 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Annual Reporting of...

  6. 39 CFR 3055.32 - Measurement systems using a delivery factor.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Measurement systems using a delivery factor. 3055.32 Section 3055.32 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Periodic Reporting of Service Performance Achievements §...

  7. A monetary incentive increases postal survey response rates for pharmacists

    PubMed Central

    Paul, C.; Walsh, R.; Tzelepis, F.

    2005-01-01

    Background: Achieving acceptable response rates from health care providers via postal questionnaires is an ongoing challenge. The use of monetary incentives is one of the most effective strategies for increasing response rates. However, the effect and cost of such an incentive on retail pharmacists' response rates has not been well studied. Methods: A sample of 700 pharmacies was selected at random from the electronic Yellow Pages in NSW Australia and mailed a brief survey regarding pharmacotherapies and advice for smoking cessation. Half of the sample was randomly allocated to receive an offer of an US$14 gift voucher. Results: The response rates were 65.9% for the voucher group and 53.5% for the no-voucher group. The odds of response from the voucher group was 1.68 (95%CI = 1.23, 2.30) times greater than for the no-voucher group. The cost per additional respondent was US$67.95. The incentive also reduced follow up costs by 10%. Conclusions: A moderately sized monetary incentive is able to achieve a significant increase in response rates for retail pharmacists, thereby reducing potential bias in the sample. PMID:16286502

  8. Dosimetric investigations on Mars-96 mission.

    PubMed

    Semkova, J; Dachev, T s; Matviichuk, Y u; Koleva, R; Tomov, B; Baynov, P; Petrov, V; Nguyen, V; Siegrist, M; Chene, J; d'Uston, C; Cotin, F

    1994-10-01

    The dosimetric experiments Dose-M and Liulin as part of the more complex French-German-Bulgarian-Russian experiments for the investigation of the radiation environment for Mars-96 mission are described. The experiments will be realized with dosemeter-radiometer instruments, measuring absorbed dose in semiconductor detectors and the particle flux. Two detectors will be mounted on board the Mars-96 orbiter. Another detector will be on the guiderope of the Mars-96 Aerostate station. The scientific aims of Dose-M and Liulin experiments are: Analysis of the absorbed dose and the flux on the path and around Mars behind different shielding. Study of the shielding characteristics of the Martian atmosphere from galactic and solar cosmic rays including solar proton events. Together with the French gamma-spectrometer and the German neutron detectors the investigation of the radiation environment on the surface of Mars and in the atmosphere up to 4000 m altitude will be conducted.

  9. Thermoluminescence dosimetric characteristics of beta irradiated salt.

    PubMed

    Murthy, K V R; Pallavi, S P; Rahul, G; Patel, Y S; Sai Prasad, A S; Elangovan, D

    2006-01-01

    The thermoluminescence (TL) characteristics of sodium chloride (NaCl), known as common salt, used for cooking purposes (iodised salt), have been studied in the present paper considering its usage as an 'accidental dosemeter' in the case of a nuclear fallout. TL characteristics of common salt have been examined under excitation with a beta dose of 20 Gy from a 90Sr beta source. The salt specimens are used in the form of discs. The average salt grain that sticks to the disc is measured to be approximately 1 mg. The TL of the beta irradiated salt is recorded in the conventional TL apparatus. Initially three peaks were observed at 133, 205 and 238 degrees C. All three peaks are well resolved, having maximum intensity at 238 degrees C. The material under investigation, i.e. 'common salt' possesses many good dosimetric properties and therefore this can be considered as an 'accidental dosemeter'.

  10. Dosimetric verification of gated delivery of electron beams using a 2D ion chamber array

    PubMed Central

    Yoganathan, S. A.; Das, K. J. Maria; Raj, D. Gowtham; Kumar, Shaleen

    2015-01-01

    The purpose of this study was to compare the dosimetric characteristics; such as beam output, symmetry and flatness between gated and non-gated electron beams. Dosimetric verification of gated delivery was carried for all electron beams available on Varian CL 2100CD medical linear accelerator. Measurements were conducted for three dose rates (100 MU/min, 300 MU/min and 600 MU/min) and two respiratory motions (breathing period of 4s and 8s). Real-time position management (RPM) system was used for the gated deliveries. Flatness and symmetry values were measured using Imatrixx 2D ion chamber array device and the beam output was measured using plane parallel ion chamber. These detector systems were placed over QUASAR motion platform which was programmed to simulate the respiratory motion of target. The dosimetric characteristics of gated deliveries were compared with non-gated deliveries. The flatness and symmetry of all the evaluated electron energies did not differ by more than 0.7 % with respect to corresponding non-gated deliveries. The beam output variation of gated electron beam was less than 0.6 % for all electron energies except for 16 MeV (1.4 %). Based on the results of this study, it can be concluded that Varian CL2100 CD is well suitable for gated delivery of non-dynamic electron beams. PMID:26170552

  11. Dosimetric characterization of a bi-directional micromultileaf collimator for stereotactic applications.

    PubMed

    Bucciolini, M; Russo, S; Banci Buonamici, F; Pini, S; Silli, P

    2002-07-01

    A 6 MV photon beam from Linac SL75-5 has been collimated with a new micromultileaf device that is able to shape the field in the two orthogonal directions with four banks of leaves. This is the first clinical installation of the collimator and in this paper the dosimetric characterization of the system is reported. The dosimetric parameters required by the treatment planning system used for the dose calculation in the patient are: tissue maximum ratios, output factors, transmission and leakage of the leaves, penumbra values. Ionization chambers, silicon diode, radiographic films, and LiF thermoluminescent dosimeters have been employed for measurements of absolute dose and beam dosimetric data. Measurements with different dosimeters supply results in reasonable agreement among them and consistent with data available in literature for other models of micromultileaf collimator; that permits the use of the measured parameters for clinical applications. The discrepancies between results obtained with the different detectors (around 2%) for the analyzed parameters can be considered an indication of the accuracy that can be reached by current stereotactic dosimetry.

  12. Dosimetric verification of gated delivery of electron beams using a 2D ion chamber array.

    PubMed

    Yoganathan, S A; Das, K J Maria; Raj, D Gowtham; Kumar, Shaleen

    2015-01-01

    The purpose of this study was to compare the dosimetric characteristics; such as beam output, symmetry and flatness between gated and non-gated electron beams. Dosimetric verification of gated delivery was carried for all electron beams available on Varian CL 2100CD medical linear accelerator. Measurements were conducted for three dose rates (100 MU/min, 300 MU/min and 600 MU/min) and two respiratory motions (breathing period of 4s and 8s). Real-time position management (RPM) system was used for the gated deliveries. Flatness and symmetry values were measured using Imatrixx 2D ion chamber array device and the beam output was measured using plane parallel ion chamber. These detector systems were placed over QUASAR motion platform which was programmed to simulate the respiratory motion of target. The dosimetric characteristics of gated deliveries were compared with non-gated deliveries. The flatness and symmetry of all the evaluated electron energies did not differ by more than 0.7 % with respect to corresponding non-gated deliveries. The beam output variation of gated electron beam was less than 0.6 % for all electron energies except for 16 MeV (1.4 %). Based on the results of this study, it can be concluded that Varian CL2100 CD is well suitable for gated delivery of non-dynamic electron beams.

  13. Aquifer thermal energy storage at Mid-Island postal facility: Phase 1 final report

    SciTech Connect

    Marseille, T.J.; Armstrong, P.R.; Brown, D.R.; Vail, L.W.; Kannberg, L.D.

    1993-05-01

    The successful widespread commercialization of aquifer thermal energy storage (ATES) in the United States will depend on how experiences gained from early full-scale projects are used as guides in the design, installation, and operation of future projects. One early system, built in the mid-1980s, is the US Postal Service (USPS) Mid-Island Mail Processing Facility (MPF), in Melville, New York. The heating, ventilation, and air conditioning (HVAC) of the MPF's workroom is provided by an ATES system, which is operated year-round to provide a source for both heating and cooling, in combination with a triethylene glycol (TEG) liquid-desiccant system for humidity control. Because the facility affords a unique opportunity to study this innovative system, the US Department of Energy's (DOE) Pacific Northwest Laboratory (PNL) entered into agreements with the USPS, the US Geological Survey (USGS), and the New York State Energy Research and Development Authority (the Energy Authority) to assess the operation and performance of the system. Two essentially independent questions were to be addressed by the project. The first question was: How does the MPF ATES/TEG technology compare to conventional technologies '' The second was: What can be done to make operation of the USPS MPF more economical '' Modelling of the MPF ATES/TEG HVAC system and its loads helped to address both of these questions by showing how much energy is used by the different system components. This report is divided into six sections. Section 1 is an introduction. Section 2 provides system background. Section 3 describes PNL's technical performance assessment of the system. Section 4 discusses the life-cycle cost assessment. An operational assessment of the liquid-desiccant system is discussed in Section 5. Section 6 contains conclusions of this study.

  14. Aquifer thermal energy storage at Mid-Island postal facility: Phase 1 final report

    SciTech Connect

    Marseille, T.J.; Armstrong, P.R.; Brown, D.R.; Vail, L.W.; Kannberg, L.D.

    1993-05-01

    The successful widespread commercialization of aquifer thermal energy storage (ATES) in the United States will depend on how experiences gained from early full-scale projects are used as guides in the design, installation, and operation of future projects. One early system, built in the mid-1980s, is the US Postal Service (USPS) Mid-Island Mail Processing Facility (MPF), in Melville, New York. The heating, ventilation, and air conditioning (HVAC) of the MPF`s workroom is provided by an ATES system, which is operated year-round to provide a source for both heating and cooling, in combination with a triethylene glycol (TEG) liquid-desiccant system for humidity control. Because the facility affords a unique opportunity to study this innovative system, the US Department of Energy`s (DOE) Pacific Northwest Laboratory (PNL) entered into agreements with the USPS, the US Geological Survey (USGS), and the New York State Energy Research and Development Authority (the Energy Authority) to assess the operation and performance of the system. Two essentially independent questions were to be addressed by the project. The first question was: ``How does the MPF ATES/TEG technology compare to conventional technologies?`` The second was: ``What can be done to make operation of the USPS MPF more economical?`` Modelling of the MPF ATES/TEG HVAC system and its loads helped to address both of these questions by showing how much energy is used by the different system components. This report is divided into six sections. Section 1 is an introduction. Section 2 provides system background. Section 3 describes PNL`s technical performance assessment of the system. Section 4 discusses the life-cycle cost assessment. An operational assessment of the liquid-desiccant system is discussed in Section 5. Section 6 contains conclusions of this study.

  15. Dosimetric Comparison of Helical Tomotherapy and Dynamic Conformal Arc Therapy in Stereotactic Radiosurgery for Vestibular Schwannomas

    SciTech Connect

    Lee, Tsair-Fwu; Chao, Pei-Ju; Wang, Chang-Yu; Lan, Jen-Hong; Huang, Yu-Je; Hsu, Hsuan-Chih; Sung, Chieh-Cheng; Su, Te-Jen; Lian, Shi-Long; Fang, Fu-Min

    2011-04-01

    The dosimetric results of stereotactic radiosurgery (SRS) for vestibular schwannoma (VS) performed using dynamic conformal arc therapy (DCAT) with the Novalis system and helical TomoTherapy (HT) were compared using plan quality indices. The HT plans were created for 10 consecutive patients with VS previously treated with SRS using the Novalis system. The dosimetric indices used to compare the techniques included the conformity index (CI) and homogeneity index (HI) for the planned target volume (PTV), the comprehensive quality index (CQI) for nine organs at risk (OARs), gradient score index (GSI) for the dose drop-off outside the PTV, and plan quality index (PQI), which was verified using the plan quality discerning power (PQDP) to incorporate 3 plan indices, to evaluate the rival plans. The PTV ranged from 0.27-19.99 cm{sup 3} (median 3.39 cm{sup 3}), with minimum required PTV prescribed doses of 10-16 Gy (median 12 Gy). Both systems satisfied the minimum required PTV prescription doses. HT conformed better to the PTV (CI: 1.51 {+-} 0.23 vs. 1.94 {+-} 0.34; p < 0.01), but had a worse drop-off outside the PTV (GSI: 40.3 {+-} 10.9 vs. 64.9 {+-} 13.6; p < 0.01) compared with DCAT. No significant difference in PTV homogeneity was observed (HI: 1.08 {+-} 0.03 vs. 1.09 {+-} 0.02; p = 0.20). HT had a significantly lower maximum dose in 4 OARs and significant lower mean dose in 1 OAR; by contrast, DCAT had a significantly lower maximum dose in 1 OAR and significant lower mean dose in 2 OARs, with the CQI of the 9 OARs = 0.92 {+-} 0.45. Plan analysis using PQI (HT 0.37 {+-} 0.12 vs. DCAT 0.65 {+-} 0.08; p < 0.01), and verified using the PQDP, confirmed the dosimetric advantage of HT. However, the HT system had a longer beam-on time (33.2 {+-} 7.4 vs. 4.6 {+-} 0.9 min; p < 0.01) and consumed more monitor units (16772 {+-} 3803 vs. 1776 {+-} 356.3; p < 0.01). HT had a better dose conformity and similar dose homogeneity but worse dose gradient than DCAT. Plan analysis

  16. Dosimetric comparison of helical tomotherapy and dynamic conformal arc therapy in stereotactic radiosurgery for vestibular schwannomas.

    PubMed

    Lee, Tsair-Fwu; Chao, Pei-Ju; Wang, Chang-Yu; Lan, Jen-Hong; Huang, Yu-Je; Hsu, Hsuan-Chih; Sung, Chieh-Cheng; Su, Te-Jen; Lian, Shi-Long; Fang, Fu-Min

    2011-01-01

    The dosimetric results of stereotactic radiosurgery (SRS) for vestibular schwannoma (VS) performed using dynamic conformal arc therapy (DCAT) with the Novalis system and helical TomoTherapy (HT) were compared using plan quality indices. The HT plans were created for 10 consecutive patients with VS previously treated with SRS using the Novalis system. The dosimetric indices used to compare the techniques included the conformity index (CI) and homogeneity index (HI) for the planned target volume (PTV), the comprehensive quality index (CQI) for nine organs at risk (OARs), gradient score index (GSI) for the dose drop-off outside the PTV, and plan quality index (PQI), which was verified using the plan quality discerning power (PQDP) to incorporate 3 plan indices, to evaluate the rival plans. The PTV ranged from 0.27-19.99 cm(3) (median 3.39 cm(3)), with minimum required PTV prescribed doses of 10-16 Gy (median 12 Gy). Both systems satisfied the minimum required PTV prescription doses. HT conformed better to the PTV (CI: 1.51 ± 0.23 vs. 1.94 ± 0.34; p < 0.01), but had a worse drop-off outside the PTV (GSI: 40.3 ± 10.9 vs. 64.9 ± 13.6; p < 0.01) compared with DCAT. No significant difference in PTV homogeneity was observed (HI: 1.08 ± 0.03 vs. 1.09 ± 0.02; p = 0.20). HT had a significantly lower maximum dose in 4 OARs and significant lower mean dose in 1 OAR; by contrast, DCAT had a significantly lower maximum dose in 1 OAR and significant lower mean dose in 2 OARs, with the CQI of the 9 OARs = 0.92 ± 0.45. Plan analysis using PQI (HT 0.37 ± 0.12 vs. DCAT 0.65 ± 0.08; p < 0.01), and verified using the PQDP, confirmed the dosimetric advantage of HT. However, the HT system had a longer beam-on time (33.2 ± 7.4 vs. 4.6 ± 0.9 min; p < 0.01) and consumed more monitor units (16772 ± 3803 vs. 1776 ± 356.3; p < 0.01). HT had a better dose conformity and similar dose homogeneity but worse dose gradient than DCAT. Plan analysis confirmed the dosimetric advantage of HT

  17. TU-D-9A-01: TG176: Dosimetric Effects of Couch Tops and Immobilization Devices

    SciTech Connect

    Olch, A

    2014-06-15

    The dosimetric impact from devices external to the patient is a complex combination of increased skin dose, reduced tumor dose, and altered dose distribution. Although small monitor unit or dose corrections are routinely made for blocking trays, ion chamber correction factors, or tissue inhomogeneities, the dose perturbation of the treatment couch top or immobilization devices are often overlooked. These devices also increase surface dose, an effect which is also often ignored or underestimated. These concerns have grown recently due to the increased use of monolithic carbon fiber couch tops which are optimal for imaging for patient position verification but cause attenuation and increased surface dose compared to the ‘tennis racket’ style couch top they often replace. Also, arc delivery techniques have replaced stationary gantry techniques which cause a greater fraction of the dose to be delivered from posterior angles. A host of immobilization devices are available and used to increase patient positioning reproducibility, and these also have attenuation and skin dose implications which are often ignored. This report of Task Group 176 serves to present a survey of published data that illustrates the magnitude of the dosimetric effects of a wide range of devices external to the patient. The report also provides methods for modeling couch tops in treatment planning systems so the physicist can accurately compute the dosimetric effects for indexed patient treatments. Both photon and proton beams are considered. A discussion on avoidance of high density structures during beam planning is also provided. An important aspect of this report are the recommendations we make to clinical physicists, treatment planning system vendors, and device vendors on how to make measurements of skin dose and attenuation, how to report these values, and for the vendors, an appeal is made to work together to provide accurate couch top models in planning systems. Learning Objectives

  18. Effect of photon energy spectrum on dosimetric parameters of brachytherapy sources

    PubMed Central

    Ghorbani, Mahdi; Davenport, David

    2016-01-01

    Abstract Aim The aim of this study is to quantify the influence of the photon energy spectrum of brachytherapy sources on task group No. 43 (TG-43) dosimetric parameters. Background Different photon spectra are used for a specific radionuclide in Monte Carlo simulations of brachytherapy sources. Materials and methods MCNPX code was used to simulate 125I, 103Pd, 169Yb, and 192Ir brachytherapy sources. Air kerma strength per activity, dose rate constant, radial dose function, and two dimensional (2D) anisotropy functions were calculated and isodose curves were plotted for three different photon energy spectra. The references for photon energy spectra were: published papers, Lawrence Berkeley National Laboratory (LBNL), and National Nuclear Data Center (NNDC). The data calculated by these photon energy spectra were compared. Results Dose rate constant values showed a maximum difference of 24.07% for 103Pd source with different photon energy spectra. Radial dose function values based on different spectra were relatively the same. 2D anisotropy function values showed minor differences in most of distances and angles. There was not any detectable difference between the isodose contours. Conclusions Dosimetric parameters obtained with different photon spectra were relatively the same, however it is suggested that more accurate and updated photon energy spectra be used in Monte Carlo simulations. This would allow for calculation of reliable dosimetric data for source modeling and calculation in brachytherapy treatment planning systems. PMID:27247558

  19. U.S. Postal Service radon assessment and mitigation program. Progress report, September 1993--November 1994

    SciTech Connect

    Velazquez, L.E.; Petty, J.L. Jr.

    1994-12-31

    In 1992, the US Postal Service (USPS) entered into an Interagency Agreement with the Department of Energy (DOE) whereby DOE would provide technical assistance in support of the USPS Radon Assessment and Mitigation Program. To aid in this effort, DOE tasked the Hazardous Waste Remedial Actions Program (HAZWRAP), which is managed by Martin Marietta Energy Systems, Inc., for DOE under contract AC05-84OR21400. Since that time, HAZWRAP has developed and finalized the sampling protocol, mitigation diagnostic protocol, and the quality assurance and quality control procedures. These procedures were validated during the Protocol Validation (1992-1993) and Pilot Study (1993-1994) phases of the program. To date, HAZWRAP has performed approximately 16,000 radon measurements in 250 USPS buildings. Mitigation diagnostics have been performed in 27 buildings. Thus far, 13% of the measurements have been above the Environmental Protection Agency action level of 4 pCi/L. This report summarizes the pilot program radon testing data and mitigation diagnostic data for 22 sites and contains recommendations for mitigation diagnostics.

  20. College students' response rate to an incentivized combination of postal and web-based health survey.

    PubMed

    Balajti, Ilona; Daragó, László; Adány, Róza; Kósa, Karolina

    2010-06-01

    A questionnaire survey on health among students of higher education was planned. To produce a response rate high enough for the analysis in a cost-effective manner, a pilot study was carried out to test various methods of data collection. Electronic invitation by the university messaging system to fill a Web-based questionnaire, invitation by the same means to fill paper-based questionnaires at a predefined place and time with or without conditional incentives yielded response rates below 10%. Therefore, a combination of postal and Internet-based questionnaires was used for data collection enhanced with a small up-front gift and conditional incentives suggested by a student focus group. This modality resulted in a 68.6% response rate (65.2% after data cleaning). Those who responded through the Web were more likely to be males and residing in larger settlements. However, no statistically significant differences were observed on the primary health status variables with respect to modality. Use of Web-based questionnaires is recommended in combination with other data collection methods and incentives.

  1. Error Analysis of non-TLD HDR Brachytherapy Dosimetric Techniques

    NASA Astrophysics Data System (ADS)

    Amoush, Ahmad

    The American Association of Physicists in Medicine Task Group Report43 (AAPM-TG43) and its updated version TG-43U1 rely on the LiF TLD detector to determine the experimental absolute dose rate for brachytherapy. The recommended uncertainty estimates associated with TLD experimental dosimetry include 5% for statistical errors (Type A) and 7% for systematic errors (Type B). TG-43U1 protocol does not include recommendation for other experimental dosimetric techniques to calculate the absolute dose for brachytherapy. This research used two independent experimental methods and Monte Carlo simulations to investigate and analyze uncertainties and errors associated with absolute dosimetry of HDR brachytherapy for a Tandem applicator. An A16 MicroChamber* and one dose MOSFET detectors† were selected to meet the TG-43U1 recommendations for experimental dosimetry. Statistical and systematic uncertainty analyses associated with each experimental technique were analyzed quantitatively using MCNPX 2.6‡ to evaluate source positional error, Tandem positional error, the source spectrum, phantom size effect, reproducibility, temperature and pressure effects, volume averaging, stem and wall effects, and Tandem effect. Absolute dose calculations for clinical use are based on Treatment Planning System (TPS) with no corrections for the above uncertainties. Absolute dose and uncertainties along the transverse plane were predicted for the A16 microchamber. The generated overall uncertainties are 22%, 17%, 15%, 15%, 16%, 17%, and 19% at 1cm, 2cm, 3cm, 4cm, and 5cm, respectively. Predicting the dose beyond 5cm is complicated due to low signal-to-noise ratio, cable effect, and stem effect for the A16 microchamber. Since dose beyond 5cm adds no clinical information, it has been ignored in this study. The absolute dose was predicted for the MOSFET detector from 1cm to 7cm along the transverse plane. The generated overall uncertainties are 23%, 11%, 8%, 7%, 7%, 9%, and 8% at 1cm, 2cm, 3cm

  2. Dosimetric characterization of two radium sources for retrospective dosimetry studies

    SciTech Connect

    Candela-Juan, C.; Karlsson, M.; Lundell, M.; Ballester, F.; Tedgren, Å. Carlsson

    2015-05-15

    Purpose: During the first part of the 20th century, {sup 226}Ra was the most used radionuclide for brachytherapy. Retrospective accurate dosimetry, coupled with patient follow up, is important for advancing knowledge on long-term radiation effects. The purpose of this work was to dosimetrically characterize two {sup 226}Ra sources, commonly used in Sweden during the first half of the 20th century, for retrospective dose–effect studies. Methods: An 8 mg {sup 226}Ra tube and a 10 mg {sup 226}Ra needle, used at Radiumhemmet (Karolinska University Hospital, Stockholm, Sweden), from 1925 to the 1960s, were modeled in two independent Monte Carlo (MC) radiation transport codes: GEANT4 and MCNP5. Absorbed dose and collision kerma around the two sources were obtained, from which the TG-43 parameters were derived for the secular equilibrium state. Furthermore, results from this dosimetric formalism were compared with results from a MC simulation with a superficial mould constituted by five needles inside a glass casing, placed over a water phantom, trying to mimic a typical clinical setup. Calculated absorbed doses using the TG-43 formalism were also compared with previously reported measurements and calculations based on the Sievert integral. Finally, the dose rate at large distances from a {sup 226}Ra point-like-source placed in the center of 1 m radius water sphere was calculated with GEANT4. Results: TG-43 parameters [including g{sub L}(r), F(r, θ), Λ, and s{sub K}] have been uploaded in spreadsheets as additional material, and the fitting parameters of a mathematical curve that provides the dose rate between 10 and 60 cm from the source have been provided. Results from TG-43 formalism are consistent within the treatment volume with those of a MC simulation of a typical clinical scenario. Comparisons with reported measurements made with thermoluminescent dosimeters show differences up to 13% along the transverse axis of the radium needle. It has been estimated that

  3. Gamma Putty dosimetric studies in electron beam.

    PubMed

    Gloi, Aime M

    2016-01-01

    Traditionally, lead has been used for field shaping in megavoltage electron beams in radiation therapy. In this study, we analyze the dosimetric parameters of a nontoxic, high atomic number (Z = 83), bismuth-loaded material called Gamma Putty that is malleable and can be easily molded to any desired shape. First, we placed an ionization chamber at different depths in a solid water phantom under a Gamma Putty shield of thickness (t = 0, 3, 5, 10, 15, 20, and 25 mm, respectively) and measured the ionizing radiation on the central axis (CAX) for electron beam ranging in energies from 6 to 20 MeV. Next, we investigated the relationship between the relative ionization (RI) measured at a fixed depth for several Gamma Putty shield at different cutout diameters ranging from 2 to 5 cm for various beam energies and derived an exponential fitting equation for clinical purposes. The dose profiles along the CAX show that bremsstrahlung dominates for Gamma Putty thickness >15 mm. For high-energy beams (12-20 MeV) and all Gamma Putty thicknesses up to 25 mm, RI below 5% could not be achieved due to the strong bremsstrahlung component. However, Gamma Putty is a very suitable material for reducing the transmission factor below 5% and protecting underlying normal tissues for low-energy electron beams (6-9 MeV). PMID:27651563

  4. A high sensitive phosphor for dosimetric applications

    SciTech Connect

    Kore, Bhushan P. Dhoble, S. J.; Dhoble, N. S.; Lochab, S. P.

    2015-06-24

    In this study a novel TL phosphor CaMg{sub 3}(SO{sub 4}){sub 4}:Dy{sup 3+} was prepared by acid distillation method. The TL response of this phosphor towards γ-rays and carbon ion beam was tested. Good dosimetric glow curve was observed which is stable against both the type of radiations. The CaMg{sub 3}(SO{sub 4}){sub 4}:Dy{sup 3+} phosphor doped with 0.2 mol% of Dy{sup 3+}, irradiated with γ-ray shows nearly equal sensitivity to that of commercially available CaSO{sub 4}:Dy TLD phosphor whereas 3.5 times more sensitivity than CaSO{sub 4}:Dy, when irradiated with carbon ion beam. The change in glow peak intensities and glow peak temperature with variation in irradiation species and energy of ion beam is discussed here. The effect of these on trapping parameters is also illustrated.

  5. Gamma Putty dosimetric studies in electron beam

    PubMed Central

    Gloi, Aime M.

    2016-01-01

    Traditionally, lead has been used for field shaping in megavoltage electron beams in radiation therapy. In this study, we analyze the dosimetric parameters of a nontoxic, high atomic number (Z = 83), bismuth-loaded material called Gamma Putty that is malleable and can be easily molded to any desired shape. First, we placed an ionization chamber at different depths in a solid water phantom under a Gamma Putty shield of thickness (t = 0, 3, 5, 10, 15, 20, and 25 mm, respectively) and measured the ionizing radiation on the central axis (CAX) for electron beam ranging in energies from 6 to 20 MeV. Next, we investigated the relationship between the relative ionization (RI) measured at a fixed depth for several Gamma Putty shield at different cutout diameters ranging from 2 to 5 cm for various beam energies and derived an exponential fitting equation for clinical purposes. The dose profiles along the CAX show that bremsstrahlung dominates for Gamma Putty thickness >15 mm. For high-energy beams (12–20 MeV) and all Gamma Putty thicknesses up to 25 mm, RI below 5% could not be achieved due to the strong bremsstrahlung component. However, Gamma Putty is a very suitable material for reducing the transmission factor below 5% and protecting underlying normal tissues for low-energy electron beams (6–9 MeV).

  6. Gamma Putty dosimetric studies in electron beam

    PubMed Central

    Gloi, Aime M.

    2016-01-01

    Traditionally, lead has been used for field shaping in megavoltage electron beams in radiation therapy. In this study, we analyze the dosimetric parameters of a nontoxic, high atomic number (Z = 83), bismuth-loaded material called Gamma Putty that is malleable and can be easily molded to any desired shape. First, we placed an ionization chamber at different depths in a solid water phantom under a Gamma Putty shield of thickness (t = 0, 3, 5, 10, 15, 20, and 25 mm, respectively) and measured the ionizing radiation on the central axis (CAX) for electron beam ranging in energies from 6 to 20 MeV. Next, we investigated the relationship between the relative ionization (RI) measured at a fixed depth for several Gamma Putty shield at different cutout diameters ranging from 2 to 5 cm for various beam energies and derived an exponential fitting equation for clinical purposes. The dose profiles along the CAX show that bremsstrahlung dominates for Gamma Putty thickness >15 mm. For high-energy beams (12–20 MeV) and all Gamma Putty thicknesses up to 25 mm, RI below 5% could not be achieved due to the strong bremsstrahlung component. However, Gamma Putty is a very suitable material for reducing the transmission factor below 5% and protecting underlying normal tissues for low-energy electron beams (6–9 MeV). PMID:27651563

  7. A dosimetric comparison of two multileaf collimator designs.

    PubMed

    Killoran, J H; Giraud, J Y; Chin, L

    2002-08-01

    We present the results of measurements designed to compare two different multileaf collimator (MLC) designs using a novel evaluation technique. The MLC designs evaluated were: a "single-focused" MLC (SF-MLC) mounted below the jaws, and a "double-focused" MLC, which is a complete replacement for the lower jaws. The ability of each MLC to conform isodose lines to a prescribed field edge (PFE) was evaluated using film dosimetry. Circular fields, centered on axis and off axis, were used because they produce a range of "angles of approach" between the MLC leaves and the PFE. They also have the advantage that for an ideal field shaping system the resulting isodoses are concentric perfect circles, a well-defined basis for evaluation. The amplitude of the oscillations of the 50% isodose line about the PFE and the penumbra width as determined by the 20%, 80%, and 90% isodose lines was examined. We observe that the 50% isodose line oscillates around the PFE with greater amplitude for SF-MLC. We attribute this, at least in part, to the rounded ends of the SF-MLC leaves. However, the SF-MLC has a noticeably sharper penumbra, which we attribute to its position further from the source. We conclude that these results are relevant for accurate dosimetric modeling of these devices. PMID:12201422

  8. Dosimetric Study of a Low-Dose-Rate Brachytherapy Source

    NASA Astrophysics Data System (ADS)

    Rodríguez-Villafuerte, M.; Arzamendi, S.; Díaz-Perches, R.

    Carcinoma of the cervix is the most common malignancy - in terms of both incidence and mortality - in Mexican women. Low dose rate (LDR) intracavitary brachytherapy is normally prescribed for the treatment of this disease to the vast majority of patients attending public hospitals in our country. However, most treatment planning systems being used in these hospitals still rely on Sievert integral dose calculations. Moreover, experimental verification of dose distributions are hardly ever done. In this work we present a dosimetric characterisation of the Amersham CDCS-J 137Cs source, an LDR brachytherapy source commonly used in Mexican hospitals. To this end a Monte Carlo simulation was developed, that includes a realistic description of the internal structure of the source embedded in a scattering medium. The Monte Carlo results were compared to experimental measurements of dose distributions. A lucite phantom with the same geometric characteristics as the one used in the simulation was built. Dose measurements were performed using thermoluminescent dosimeters together with commercial RadioChromic dye film. A comparison between our Monte Carlo simulation, the experimental data, and results reported in the literature is presented.

  9. Dosimetric implications of new compounds for neutron capture therapy (NCT)

    SciTech Connect

    Fairchild, R.G.

    1982-01-01

    Systemic application of radiolabeled or cytotoxic agents should allow targeting of primary and metastatic neoplasms on a cellular level. In fact, drug uptake in non-target cell pools often exceeds toxic levels before sufficient amounts are delivered to tumor. In addition, at the large concentration of molecules necessary for therapy, effects of saturation are often found. Application of NCT can circumvent problems associated with high uptake in competing non-target cell pools, as the /sup 10/B(n,..cap alpha..)/sup 7/Li reaction is activated only within the radiation field. A comparison with other modes of particle therapy indicated that NCT provides significant advantages. It is however, difficult to obtain vehicles for boron transport which demonstrate both the tumor specificity and concentration requisite for NCT. A number of biomolecules have been investigated which show both the necessary concentration and specificity. These include chlorpromazine, thiouracil, porphyrins, amino acids, and nucleosides. However, these analogs have yet to be made available for NCT. Dosimetric implications of binding sites are considered, as well as alternate neutron sources. (ERB)

  10. 39 CFR 111.2 - Availability of the Mailing Standards of the United States Postal Service, Domestic Mail Manual.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... available during regular business hours for reference and public inspection at the U.S. Postal Service Library, National Headquarters in Washington, DC. Copies of only the current issue are available during regular business hours for public inspection at area and district offices of the Postal Service and at...

  11. 39 CFR 111.2 - Availability of the Mailing Standards of the United States Postal Service, Domestic Mail Manual.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... available during regular business hours for reference and public inspection at the U.S. Postal Service Library, National Headquarters in Washington, DC. Copies of only the current issue are available during regular business hours for public inspection at area and district offices of the Postal Service and at...

  12. 39 CFR 111.2 - Availability of the Mailing Standards of the United States Postal Service, Domestic Mail Manual.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... available during regular business hours for reference and public inspection at the U.S. Postal Service Library, National Headquarters in Washington, DC. Copies of only the current issue are available during regular business hours for public inspection at area and district offices of the Postal Service and at...

  13. 39 CFR 111.2 - Availability of the Mailing Standards of the United States Postal Service, Domestic Mail Manual.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... available during regular business hours for reference and public inspection at the U.S. Postal Service Library, National Headquarters in Washington, DC. Copies of only the current issue are available during regular business hours for public inspection at area and district offices of the Postal Service and at...

  14. Dosimetric properties of the Theraview fluoroscopic electronic portal imaging device.

    PubMed

    Glendinning, A G; Bonnett, D E

    2000-05-01

    Electronic portal imaging devices (EPIDs) can be used for non-imaging applications in radiotherapy such as patient dosimetry. Of the systems available, the fluoroscopic camera-based EPID Theraview (InfiMed Inc.) has not been studied to date, and a review of the dosimetric properties of the system is presented here. In the "single set-up" mode of image acquisition, pixel intensity increases sublinearly with applied dose. The response was dependent on the system's video signal gain and showed a threshold dose to the detector in the range 0.05-0.35 cGy, and pixel saturation at detector doses in the range 1.2-1.6 cGy. Repeated exposures of the EPID were observed to be extremely reproducible (standard deviation 0.5%). The sensitivity of the system showed a linear decline of 0.04% day-1 over a 68-day period, during which time the relative off-axis response within 10 x 10 cm2 field was constant to within a standard deviation of 0.56%. The system shows spatial non-uniformity, which requires correction for application to dose measurements in two-dimensions. Warm-up of the camera control unit required a period of at least 40 min and was associated with an enhancement in pixel intensity of up to 12%. A radiation dose history effect was observed at doses as low as 0.2 Gy. Camera dark current was shown to be negligible at normal accelerator operation. No discernible image distortion was found. Mechanical stability on gantry rotation was also assessed and image displacement of up to 5 mm at the isocentre was observed. It was concluded that the device could be used for dosimetry provided necessary precautions were observed and corrections made. PMID:10884749

  15. Adaptive optimization by 6 DOF robotic couch in prostate volumetric IMRT treatment: rototranslational shift and dosimetric consequences.

    PubMed

    Chiesa, Silvia; Placidi, Lorenzo; Azario, Luigi; Mattiucci, Gian Carlo; Greco, Francesca; Damiani, Andrea; Mantini, Giovanna; Frascino, Vincenzo; Piermattei, Angelo; Valentini, Vincenzo; Balducci, Mario

    2015-01-01

    The purpose of this study was to investigate the magnitude and dosimetric relevance of translational and rotational shifts on IGRT prostate volumetric-modulated arc therapy (VMAT) using Protura six degrees of freedom (DOF) Robotic Patient Positioning System. Patients with cT3aN0M0 prostate cancer, treated with VMAT simultaneous integrated boost (VMAT-SIB), were enrolled. PTV2 was obtained adding 0.7 cm margin to seminal vesicles base (CTV2), while PTV1 adding to prostate (CTV1) 0.7 cm margin in all directions, except 1.2 cm, as caudal margin. A daily CBCT was acquired before dose delivery. The translational and rotational displacements were corrected through Protura Robotic Couch, collected and applied to the simulation CT to obtain a translated CT (tCT) and a rototranslated CT (rtCT) on which we recalculated the initial treatment plan (TP). We analyzed the correlation between dosimetric coverage, organs at risk (OAR) sparing, and translational or rotational displacements. The dosimetric impact of a rototranslational correction was calculated. From October 2012 to September 2013, a total of 263 CBCT scans from 12 patients were collected. Translational shifts were < 5 mm in 81% of patients and the rotational shifts were < 2° in 93% of patient scans. The dosimetric analysis was performed on 172 CBCT scans and calculating 344 VMAT-TP. Two significant linear correlations were observed between yaw and the V20 femoral heads and between pitch rotation and V50 rectum (p < 0.001); rototranslational correction seems to impact more on PTV2 than on PTV1, especially when margins are reduced. Rotational errors are of dosimetric significance in sparing OAR and in target coverage. This is relevant for femoral heads and rectum because of major distance from isocenter, and for seminal vesicles because of irregular shape. No correlation was observed between translational and rotational errors. A study considering the intrafractional error and the deformable registration is ongoing.

  16. Dosimetric measurements of an n-butyl cyanoacrylate embolization material for arteriovenous malformations

    SciTech Connect

    Labby, Zacariah E.; Chaudhary, Neeraj; Gemmete, Joseph J.; Pandey, Aditya S.; Roberts, Donald A.

    2015-04-15

    Purpose: The therapeutic regimen for cranial arteriovenous malformations often involves both stereotactic radiosurgery and endovascular embolization. Embolization agents may contain tantalum or other contrast agents to assist the neurointerventionalists, leading to concerns regarding the dosimetric effects of these agents. This study investigated dosimetric properties of n-butyl cyanoacrylate (n-BCA) plus lipiodol with and without tantalum powder. Methods: The embolization agents were provided cured from the manufacturer with and without added tantalum. Attenuation measurements were made for the samples and compared to the attenuation of a solid water substitute using a 6 MV photon beam. Effective linear attenuation coefficients (ELAC) were derived from attenuation measurements made using a portal imager and derived sample thickness maps projected in an identical geometry. Probable dosimetric errors for calculations in which the embolized regions are overridden with the properties of water were calculated using the ELAC values. Interface effects were investigated using a parallel plate ion chamber placed at set distances below fixed samples. Finally, Hounsfield units (HU) were measured using a stereotactic radiosurgery CT protocol, and more appropriate HU values were derived from the ELAC results and the CT scanner’s HU calibration curve. Results: The ELAC was 0.0516 ± 0.0063 cm{sup −1} and 0.0580 ± 0.0091 cm{sup −1} for n-BCA without and with tantalum, respectively, compared to 0.0487 ± 0.0009 cm{sup −1} for the water substitute. Dose calculations with the embolized region set to be water equivalent in the treatment planning system would result in errors of −0.29% and −0.93% per cm thickness of n-BCA without and with tantalum, respectively. Interface effects compared to water were small in magnitude and limited in distance for both embolization materials. CT values at 120 kVp were 2082 and 2358 HU for n-BCA without and with tantalum, respectively

  17. Electromagnetic and Thermal Dosimetric Techniques in Humans and its Application

    NASA Astrophysics Data System (ADS)

    Hirata, Akimasa; Fujiwara, Osamu

    There has been increasing public concern about the adverse health effects of human exposure to radio frequency fields. Radio frequency fields are also used for medical application. This paper reviews electromagnetic and thermal computational dosimetric techniques, which has been developed by the authors. The feature of the thermal dosimetric method is that body core temperature can be computed reasonably unlike conventional method. This scheme is particularly useful for intense localized or whole-body electromagnetic wave exposure. Computational examples are shown to verify the effectiveness of the proposal.

  18. 22 CFR 123.24 - Shipments by U.S. Postal Service.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... subchapter by clearly marking on the package “This export is subject to the controls of the ITAR, 22 CFR... controls of the ITAR, 22 CFR (identify section for an exemption) or (state license number).” For those... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Shipments by U.S. Postal Service....

  19. Female Spirituality, Careering and the U.S. Postal Service, Maintenance Division.

    ERIC Educational Resources Information Center

    Carver, Kimberly D.; Gallaher, Rex M.; Richmond, Lee J.

    This paper discusses a study examining the lives of women (N=9) involved as either mentors or proteges in the U.S. Postal Service's Maintenance Leadership Program. Participant interviews consisted of the completion of several instruments including a personality inventory, a measure of agentic versus communal values, an instrument that examines…

  20. 75 FR 16837 - Public Review of Draft United States Thoroughfare, Landmark, and Postal Address Data Standard

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-02

    ... sent to Julie Binder Maitra, of the FGDC Secretariat via electronic mail, jmaitra@usgs.gov by June 16... notification of how their comments were addressed by electronic or postal mail. After formal endorsement of the... apply to addresses of entities lacking a spatial component and specifically excludes...

  1. 14 CFR 302.714 - Availability of data to the U.S. Postal Service.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Availability of data to the U.S. Postal Service. 302.714 Section 302.714 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) PROCEDURAL REGULATIONS RULES OF PRACTICE IN PROCEEDINGS Rules Applicable to Mail Rate Proceedings and Mail...

  2. 22 CFR 123.24 - Shipments by U.S. Postal Service.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... subchapter by clearly marking on the package “This export is subject to the controls of the ITAR, 22 CFR... controls of the ITAR, 22 CFR (identify section for an exemption) or (state license number).” For those... defense hardware using a license or exemption in this subchapter by the U.S. Postal Service must be...

  3. POLLUTION PREVENTION OPPORTUNITY ASSESSMENT: GENERAL MAIL AND VEHICLE MAINTENANCE FACILITY, UNITED STATES POSTAL SERVICE, BUFFALO, NY

    EPA Science Inventory

    The Pollution Prevention Opportunity Assessment (PPOA) summarized here was conducted at a U.S.Postal Service (USPS) Facility in Buffalo, NY. The PPOA documented and quantified waste generation at the General Mail Facility (GMF) where mail is processed, and at the Vehicle Maintena...

  4. Dosimetric and mechanical characteristics of a commercial dynamic {mu}MLC used in SRS

    SciTech Connect

    Galal, Mohamed M.; Keogh, Sinead; Khalil, Sultan

    2011-07-15

    Purpose: The aim of this work is to carry out mechanical and dosimetric assessments on a commercial dynamic micromulti leaf collimator system to be used for stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT). Mechanical parameters such as leaf position accuracy with different gantry angles and leaf position reproducibility were measured. Also dosimetric measurements of the interleaf leakage, intraleaf transmission, penumbra width, and light field alignment were carried out. Furthermore, measurements of output factors (S{sub cp}) and in-air factors (S{sub c}) for the {mu}MLC system will be reported. Methods: EBT2 films were used to assess the leaf position error with gantry angle and after stress test, penumbra width and light field alignment. Leaf leakage was quantified using both EBT2 film and a pinpoint ion chamber. With regard to output factors, the pinpoint chamber was placed in a water phantom at 10 cm depth and 100 cm SSD. For in-air output factor measurements, 0.2 cm of brass was placed above the photon diode as build-up. Results: Measurements of mechanical parameters gave values of 0.05 cm (SD 0.035) for the average leaf position accuracy for different gantry angles and after stress test. Dosimetric measurements, yielded values of 0.22 {+-} 0.01 and 0.24 {+-} 0.01 cm, respectively, for side and head leaf penumbras. Also, average leaf abutting, leakage and transmission were found to be 0.65, 0.91, and 0.20%, respectively. Conclusions: (a) The add-on {mu}MLC system in combination with our LINAC has been commissioned to be used for clinical purposes and showed good agreement with published results for different {mu}MLC types. (b) This work has lead to the recommendation that leaves should be recalibrated after ten static beams or after each dynamic arc.

  5. Dosimetric effects caused by couch tops and immobilization devices: Report of AAPM Task Group 176

    SciTech Connect

    Olch, Arthur J.; Gerig, Lee; Li, Heng; Mihaylov, Ivaylo; Morgan, Andrew

    2014-06-15

    The dosimetric impact from devices external to the patient is a complex combination of increased skin dose, reduced tumor dose, and altered dose distribution. Although small monitor unit or dose corrections are routinely made for blocking trays, ion chamber correction factors, e.g., accounting for temperature and pressure, or tissue inhomogeneities, the dose perturbation of the treatment couch top or immobilization devices is often overlooked. These devices also increase skin dose, an effect which is also often ignored or underestimated. These concerns have grown recently due to the increased use of monolithic carbon fiber couch tops which are optimal for imaging for patient position verification but cause attenuation and increased skin dose compared to the “tennis racket” style couch top they often replace. Also, arc delivery techniques have replaced stationary gantry techniques which cause a greater fraction of the dose to be delivered from posterior angles. A host of immobilization devices are available and used to increase patient positioning reproducibility, and these also have attenuation and skin dose implications which are often ignored. This report of Task Group 176 serves to present a survey of published data that illustrates the magnitude of the dosimetric effects of a wide range of devices external to the patient. The report also provides methods for modeling couch tops in treatment planning systems so the physicist can accurately compute the dosimetric effects for indexed patient treatments. Both photon and proton beams are considered. A discussion on avoidance of high density structures during beam planning is also provided. An important aspect of this report are the recommendations the authors make to clinical physicists, treatment planning system vendors, and device vendors on how to make measurements of surface dose and attenuation and how to report these values. For the vendors, an appeal is made to work together to provide accurate couch top

  6. Assessment of dosimetrical performance in 11 Varian a-Si500 electronic portal imaging devices

    NASA Astrophysics Data System (ADS)

    Kavuma, Awusi; Glegg, Martin; Currie, Garry; Elliott, Alex

    2008-12-01

    Dosimetrical characteristics of 11 Varian a-Si-500 electronic portal imaging devices (EPIDs) in clinical use for periods ranging between 10 and 86 months were investigated for consistency of performance and portal dosimetry implications. Properties studied include short-term reproducibility, signal linearity with monitor units, response to reference beam, signal uniformity across the detector panel, signal dependence on field size, dose-rate influence, memory effects and image profiles as a function of monitor units. The EPID measurements were also compared with those of the ionization chambers' to ensure stability of the linear accelerators. Depending on their clinical installation date, the EPIDs were interfaced with one of the two different acquisition control software packages, IAS2/IDU-II or IAS3/IDU-20. Both the EPID age and image acquisition system influenced the dosimetric characteristics with the newer version (IAS3 with IDU-20) giving better data reproducibility and linearity fit than the older version (IAS2 with IDU-II). The relative signal response (uniformity) after 50 MU was better than 95% of the central value and independent of detector. Sensitivity for all EPIDs reduced continuously with increasing dose rates for the newer image acquisition software. In the dose-rate range 100-600 MU min-1, the maximum variation in sensitivity ranged between 1 and 1.8% for different EPIDs. For memory effects, the increase in the measured signal at the centre of the irradiated field for successive images was within 1.8% and 1.0% for the older and newer acquisition systems, respectively. Image profiles acquired at a lower MU in the radial plane (gun-target) had gradients in measured pixel values of up to 25% for the older system. Detectors with software/hardware versions IAS3/IDU-20 have a high degree of accuracy and are more suitable for routine quantitative IMRT dosimetrical verification.

  7. Dosimetric effects caused by couch tops and immobilization devices: report of AAPM Task Group 176.

    PubMed

    Olch, Arthur J; Gerig, Lee; Li, Heng; Mihaylov, Ivaylo; Morgan, Andrew

    2014-06-01

    The dosimetric impact from devices external to the patient is a complex combination of increased skin dose, reduced tumor dose, and altered dose distribution. Although small monitor unit or dose corrections are routinely made for blocking trays, ion chamber correction factors, e.g., accounting for temperature and pressure, or tissue inhomogeneities, the dose perturbation of the treatment couch top or immobilization devices is often overlooked. These devices also increase skin dose, an effect which is also often ignored or underestimated. These concerns have grown recently due to the increased use of monolithic carbon fiber couch tops which are optimal for imaging for patient position verification but cause attenuation and increased skin dose compared to the "tennis racket" style couch top they often replace. Also, arc delivery techniques have replaced stationary gantry techniques which cause a greater fraction of the dose to be delivered from posterior angles. A host of immobilization devices are available and used to increase patient positioning reproducibility, and these also have attenuation and skin dose implications which are often ignored. This report of Task Group 176 serves to present a survey of published data that illustrates the magnitude of the dosimetric effects of a wide range of devices external to the patient. The report also provides methods for modeling couch tops in treatment planning systems so the physicist can accurately compute the dosimetric effects for indexed patient treatments. Both photon and proton beams are considered. A discussion on avoidance of high density structures during beam planning is also provided. An important aspect of this report are the recommendations the authors make to clinical physicists, treatment planning system vendors, and device vendors on how to make measurements of surface dose and attenuation and how to report these values. For the vendors, an appeal is made to work together to provide accurate couch top

  8. The spectral applications of Beer-Lambert law for some biological and dosimetric materials

    NASA Astrophysics Data System (ADS)

    Içelli, Orhan; Yalçin, Zeynel; Karakaya, Vatan; Ilgaz, Işıl P.

    2014-08-01

    The aim of this study is to conduct quantitative and qualitative analysis of biological and dosimetric materials which contain organic and inorganic materials and to make the determination by using the spectral theorem Beer-Lambert law. Beer-Lambert law is a system of linear equations for the spectral theory. It is possible to solve linear equations with a non-zero coefficient matrix determinant forming linear equations. Characteristic matrix of the linear equation with zero determinant is called point spectrum at the spectral theory.

  9. The revised International Commission on Radiological Protection (ICRP) dosimetric model for the human respiratory tract

    SciTech Connect

    Bair, W.J.

    1992-05-01

    A task group has revised the dosimetric model of the respiratory tract used to calculate annual limits on intake of radionuclides. The revised model can be used to project respiratory tract doses for workers and members of the public from airborne radionuclides and to assess past exposures. Doses calculated for specific extrathoracic and thoracic tissues can be adjusted to account for differences in radiosensitivity and summed to yield two values of dose for the respiratory tract that are applicable to the ICRP tissue weighted dosimetry system.

  10. An appraisal of the utility or futility of ENT consultant postal questionnaires.

    PubMed

    Ryan, Stephen; Saunders, J; Clarke, E; Fenton, J E

    2013-03-01

    Despite an increase in ENT postal questionnaires, the quality of their methodology has been questioned (Ramphul et al. in J Laryngol Otol 119:175-178, 1). This retrospective study examined whether quality and utility of such questionnaires published since 2005 has improved. Seventeen consultant postal questionnaires published between 2005 and 2012 were reviewed. Quality of questionnaires was assessed using a 30-point score based on compliance with 15 criteria previously established to evaluate postal questionnaire study-design (Ramphul et al. in J Laryngol Otol 119:175-178, 1). Citation rates were used as an indicator of utility. The specific comments made in each citing paper was reviewed providing information on whether questionnaire findings (a) had an impact on clinical practice, (b) were the citing comments positive, (c) negative or (d) non-specific. Recurrent methodological flaws were identified in all questionnaires. The average score assigned was 44 %, versus 32 % previously reported (Ramphul et al. in J Laryngol Otol 119:175-178, 1) (P < 0.01, Student's t test). The low citation rate demonstrates poor utility for postal questionnaires. Citations were general non-specific referencing with no clear indication that questionnaire findings positively impacted clinical practice. In conclusion, although the quality of ENT postal questionnaire has improved since the original study (Ramphul et al. in J Laryngol Otol 119:175-178, 1), important recurring methodological flaws still exist. The poor utility, based on low citation rates, also reflects the continued deficiencies in design quality. It is recommended that authors of questionnaire-based research should ensure that guidelines for questionnaire design are adhered in order to improve the validity of findings and hence impact on clinical practice.

  11. Dosimetric effects of an air cavity for the SAVI partial breast irradiation applicator

    SciTech Connect

    Richardson, Susan L.; Pino, Ramiro

    2010-08-15

    Purpose: To investigate the dosimetric effect of the air inside the SAVI partial breast irradiation device. Methods: The authors have investigated how the air inside the SAVI partial breast irradiation device changes the delivered dose from the homogeneously calculated dose. Measurements were made with the device filled with air and water to allow comparison to a homogenous dose calculation done by the treatment planning system. Measurements were made with an ion chamber, TLDs, and film. Monte Carlo (MC) simulations of the experiment were done using the EGSnrc suite. The MC model was validated by comparing the water-filled calculations to those from a commercial treatment planning system. Results: The magnitude of the dosimetric effect depends on the size of the cavity, the arrangement of sources, and the relative dwell times. For a simple case using only the central catheter of the largest device, MC results indicate that the dose at the prescription point 1 cm away from the air-water boundary is about 9% higher than the homogeneous calculation. Independent measurements in a water phantom with a similar air cavity gave comparable results. MC simulation of a realistic multidwell position plan showed discrepancies of about 5% on average at the prescription point for the largest device. Conclusions: The dosimetric effect of the air cavity is in the range of 3%-9%. Unless a heterogeneous dose calculation algorithm is used, users should be aware of the possibility of small treatment planning dose errors for this device and make modifications to the treatment delivery, if necessary.

  12. Dosimetric characterization of an 192Ir brachytherapy source with the Monte Carlo code PENELOPE.

    PubMed

    Casado, Francisco Javier; García-Pareja, Salvador; Cenizo, Elena; Mateo, Beatriz; Bodineau, Coral; Galán, Pedro

    2010-01-01

    Monte Carlo calculations are highly spread and settled practice to calculate brachytherapy sources dosimetric parameters. In this study, recommendations of the AAPM TG-43U1 report have been followed to characterize the Varisource VS2000 (192)Ir high dose rate source, provided by Varian Oncology Systems. In order to obtain dosimetric parameters for this source, Monte Carlo calculations with PENELOPE code have been carried out. TG-43 formalism parameters have been presented, i.e., air kerma strength, dose rate constant, radial dose function and anisotropy function. Besides, a 2D Cartesian coordinates dose rate in water table has been calculated. These quantities are compared to this source reference data, finding results in good agreement with them. The data in the present study complement published data in the next aspects: (i) TG-43U1 recommendations are followed regarding to phantom ambient conditions and to uncertainty analysis, including statistical (type A) and systematic (type B) contributions; (ii) PENELOPE code is benchmarked for this source; (iii) Monte Carlo calculation methodology differs from that usually published in the way to estimate absorbed dose, leaving out the track-length estimator; (iv) the results of the present work comply with the most recent AAPM and ESTRO physics committee recommendations about Monte Carlo techniques, in regards to dose rate uncertainty values and established differences between our results and reference data. The results stated in this paper provide a complete parameter collection, which can be used for dosimetric calculations as well as a means of comparison with other datasets from this source.

  13. First biological and dosimetric results of the free flyer biostack experiment AO015 on LDEF

    NASA Technical Reports Server (NTRS)

    Reitz, G.; Buecker, H.; Facius, R.; Horneck, G.; Schaeffer, M.; Schott, J. U.; Bayonove, J.; Beaujean, R.; Benton, E. V.; Delpoux, M.

    1991-01-01

    The main objectives of the Biostack Experiment are to study the effectiveness of the structured components of the cosmic radiation to bacterial spores, plant seeds, and animal cysts for a long duration spaceflight and to get dosimetric data such as particle fluences and spectra and total doses for the Long Duration Exposure Facility orbit. The configuration of the experiment packages allows the localization of the trajectory of the particles in each biological layer and to correlate the potential biological impairment or injury with the physical characteristics of the responsible particle. Although the Biostack Experiment was designed for a long duration flight of only nine months, most of the biological systems show a high hatching or germination rate. Some of the first observations are an increase of the mutation rate of embryonic lethals in the second generation of Arabidopsis seeds, somatic mutations, and a reduction of growth rates of corn plants and a reduction of life span of Artemia salina shrimps. The different passive detector systems are also in a good shape and give access to a proper dosimetric analysis. The results are summarized, and some aspects of future analysis are shown.

  14. Dosimetric comparison of helical tomothearpy and linac-based IMRT in whole abdomen radiotherapy

    NASA Astrophysics Data System (ADS)

    Kang, Young-nam; Kim, Dae-Hyun; Jang, Hong Seok; Song, Jin Ho; Choi, Byung Ock; Cho, Seok Goo; Jung, Ji-Young; Kay, Chul Seung

    2012-10-01

    Recent advances in radiotherapy techniques have allowed a significant improvement in the therapeutic ratio of whole abdominal irradiation (WAI) through linear-accelerator (Linac) based intensity-modulated radiotherapy (IMRT) and helical tomotherapy (HT). IMRT has been shown to reduce the dose to organs at risk (OAR) while adequately treating the tumor volume. HT operates by adjusting 51 beam directions, couch speed, pitch and shapes of a binary multileaf collimator (MLC), with the purpose of clinically increasing the befit to the patient. We incorporated helical tomotherapy as a new modality for WAI for the treatment of non-Hodgkin's lymphoma patients whose disease involved the intestine and the mesenteric lymph nodes. Excellent tumor coverage with effective sparing of normal organ sparings, and homogeneous dose distribution could be achieved. This study dosimetrically compared HT and linac-based IMRT by using several indices, including the conformity index (CI) and the homogeneity index (HI) for the planning target volume (PTV), as well as the, max dose and the mean dose and the quality index (QI) for five organs at risk (OARs). The HI and the CI were used to compare the quality of target coverage while the QI was used compare the dosimetric performans for OAR systems. The target coverages between the two systems were similar, but the most QIs were lower than 1, what means that HT is batter at sparing OARs than IMRT. Tomotherapy enabled excellent target coverage, effective sparing of normal tissues, and homogeneous dose distribution without severe acute toxicity.

  15. Need for tighter controls over fuel purchased by the Postal Service

    SciTech Connect

    Staats, E.B.

    1980-07-31

    The US Postal Service uses nearly 90 million gallons of gasoline and diesel fuel each year. In fiscal year 1980, the cost of this fuel was expected to be $100 million, and the cost will increase as fuel prices continue to rise. This GAO study finds that the Service needs to change the way it controls fuel. To reduce the susceptibility to fraud, abuse, and waste in the procurement and use of fuel, GAO recommends that the Postmaster General vigorously enforce procedures for verifying fuel deliveries, including maintaining verification records for independent audit; initiate a program to test the quality of fuel received; insure that guidelines for bulk-tank security are followed at all facilities; insure that all fuel dispensed from bulk fuel tanks is accounted for; require drivers to obtain receipts from commercial service stations or record fuel and oil purchases on documents controlled by the Postal Service; and obtain better data on the use of fuel by vehicle drivers.

  16. Health surveys in the workplace: comparison of postal, email and World Wide Web methods.

    PubMed

    Jones, R; Pitt, N

    1999-11-01

    Health surveys in the workplace are an important part of epidemiology, needs assessment and health promotion. Since the workplace is changing rapidly with the use of computer networks, we examined the feasibility, validity and cost of health surveys using e-mail and the World Wide Web (WWW). Five hundred systematically sampled university staff in a convenience sample of 10 English universities were surveyed using either e-mail alone, e-mail plus a WWW form or postal questionnaire. Response rates, speed of response, validity and costs were examined. The postal survey obtained the best response rate: 72% as compared with 34% for e-mail alone and 19% for the WWW, but it was also the most expensive at 92p per reply, with 35p for e-mail, and 41p for the WWW. Most of the electronic responses were made within five days. In 1997, the increased response rate justified the higher cost of postal questionnaires. e-mail and WWW surveys are easy, quick and inexpensive to administer, and despite low response rates may be useful for pilot studies. The rapid changes in the spread and use of information technology means we have to keep reassessing the methods we use for health surveys in the workplace.

  17. Multi-institutional dosimetric and geometric commissioning of image-guided small animal irradiators

    SciTech Connect

    Lindsay, P. E.; Granton, P. V.; Hoof, S. van; Hermans, J.; Gasparini, A.; Jelveh, S.; Clarkson, R.; Kaas, J.; Wittkamper, F.; Sonke, J.-J.; Verhaegen, F.; Jaffray, D. A.

    2014-03-15

    Purpose: To compare the dosimetric and geometric properties of a commercial x-ray based image-guided small animal irradiation system, installed at three institutions and to establish a complete and broadly accessible commissioning procedure. Methods: The system consists of a 225 kVp x-ray tube with fixed field size collimators ranging from 1 to 44 mm equivalent diameter. The x-ray tube is mounted opposite a flat-panel imaging detector, on a C-arm gantry with 360° coplanar rotation. Each institution performed a full commissioning of their system, including half-value layer, absolute dosimetry, relative dosimetry (profiles, percent depth dose, and relative output factors), and characterization of the system geometry and mechanical flex of the x-ray tube and detector. Dosimetric measurements were made using Farmer-type ionization chambers, small volume air and liquid ionization chambers, and radiochromic film. The results between the three institutions were compared. Results: At 225 kVp, with 0.3 mm Cu added filtration, the first half value layer ranged from 0.9 to 1.0 mm Cu. The dose-rate in-air for a 40 × 40 mm{sup 2} field size, at a source-to-axis distance of 30 cm, ranged from 3.5 to 3.9 Gy/min between the three institutions. For field sizes between 2.5 mm diameter and 40 × 40 mm{sup 2}, the differences between percent depth dose curves up to depths of 3.5 cm were between 1% and 4% on average, with the maximum difference being 7%. The profiles agreed very well for fields >5 mm diameter. The relative output factors differed by up to 6% for fields larger than 10 mm diameter, but differed by up to 49% for fields ≤5 mm diameter. The mechanical characteristics of the system (source-to-axis and source-to-detector distances) were consistent between all three institutions. There were substantial differences in the flex of each system. Conclusions: With the exception of the half-value layer, and mechanical properties, there were significant differences between the

  18. Dosimetric characteristics of a new unit for electronic skin brachytherapy

    PubMed Central

    Garcia-Martinez, Teresa; Chan, Jan-Pieter; Perez-Calatayud, Jose

    2014-01-01

    Purpose Brachytherapy with radioactive high dose rate (HDR) 192Ir source is applied to small skin cancer lesions, using surface applicators, i.e. Leipzig or Valencia type. New developments in the field of radiotherapy for skin cancer include electronic brachytherapy. This technique involves the placement of an HDR X-ray source close to the skin, therefore combining the benefits of brachytherapy with the reduced shielding requirements and targeted energy of low energy X-rays. Recently, the Esteya® Electronic Brachytherapy System (Esteya EBS, Elekta AB-Nucletron, Stockholm, Sweden) has been developed specifically for HDR brachytherapy treatment of surface lesions. The system provides radionuclide free HDR brachytherapy by means of a small 69.5 kV X-ray source. The purpose of this study is to obtain the dosimetric characterization required for clinical implementation, providing the detailed methodology to perform the commissioning. Material and methods Flatness, symmetry and penumbra, percentage of depth dose (PDD), kV stability, HVL, output, spectrum, linearity, and leakage have been evaluated for a set of applicators (from 10 mm to 30 mm in diameter). Results Flatness and symmetry resulted better than 5% with around 1 mm of penumbra. The depth dose gradient is about 7%/mm. A kV value of 68.4 ± 1.0 kV (k = 1) was obtained, in good agreement with manufacturer data (69.5 kV). HVL was 1.85 mm Al. Dose rate for a typical 6 Gy to 7 Gy prescription resulted about 3.3 Gy/min and the leakage value was < 100 µGy/min. Conclusions The new Esteya® Electronic Brachytherapy System presents excellent flatness and penumbra as with the Valencia applicator case, combined with an improved PDD, allowing treatment of lesions of up to a depth of 5 mm in combination with reduced treatment duration. The Esteya unit allows HDR brachytherapy superficial treatment within a minimally shielded environment due its low energy. PMID:24790622

  19. Dosimetric Verification Using Monte Carlo Calculations for Tissue Heterogeneity-Corrected Conformal Treatment Plans Following RTOG 0813 Dosimetric Criteria for Lung Cancer Stereotactic Body Radiotherapy

    SciTech Connect

    Li Jun; Galvin, James; Harrison, Amy; Timmerman, Robert; Yu Yan; Xiao Ying

    2012-10-01

    Purpose: The recently activated Radiation Therapy Oncology Group (RTOG) studies of stereotactic body radiation therapy (SBRT) for non-small-cell lung cancer (NSCLC) require tissue density heterogeneity correction, where the high and intermediate dose compliance criteria were established based on superposition algorithm dose calculations. The study was aimed at comparing superposition algorithm dose calculations with Monte Carlo (MC) dose calculations for SBRT for NSCLC and to evaluate whether compliance criteria need to be adjusted for MC dose calculations. Methods and Materials: Fifteen RTOG 0236 study sets were used. The planning tumor volumes (PTV) ranged from 10.7 to 117.1 cm{sup 3}. SBRT conformal treatment plans were generated using XiO (CMS Inc.) treatment planning software with superposition algorithm to meet the dosimetric high and intermediate compliance criteria recommended by the RTOG 0813 protocol. Plans were recalculated using the MC algorithm of a Monaco (CMS, Inc.) treatment planning system. Tissue density heterogeneity correction was applied in both calculations. Results: Overall, the dosimetric quantities of the MC calculations have larger magnitudes than those of the superposition calculations. On average, R{sub 100%} (ratio of prescription isodose volume to PTV), R{sub 50%} (ratio of 50% prescription isodose volume to PTV), D{sub 2cm} (maximal dose 2 cm from PTV in any direction as a percentage of prescription dose), and V{sub 20} (percentage of lung receiving dose equal to or larger than 20 Gy) increased by 9%, 12%, 7%, and 18%, respectively. In the superposition plans, 3 cases did not meet criteria for R{sub 50%} or D{sub 2cm}. In the MC-recalculated plans, 8 cases did not meet criteria for R{sub 100%}, R{sub 50%}, or D{sub 2cm}. After reoptimization with MC calculations, 5 cases did not meet the criteria for R{sub 50%} or D{sub 2cm}. Conclusions: Results indicate that the dosimetric criteria, e.g., the criteria for R{sub 50%} recommended by

  20. Responsibility for managing musculoskeletal disorders – A cross-sectional postal survey of attitudes

    PubMed Central

    Larsson, Maria EH; Nordholm, Lena A

    2008-01-01

    Background Musculoskeletal disorders are a major burden on individuals, health systems and social care systems and rehabilitation efforts in these disorders are considerable. Self-care is often considered a cost effective treatment alternative owing to limited health care resources. But what are the expectations and attitudes in this question in the general population? The purpose of this study was to describe general attitudes to responsibility for the management of musculoskeletal disorders and to explore associations between attitudes and background variables. Methods A cross-sectional, postal questionnaire survey was carried out with a random sample of a general adult Swedish population of 1770 persons. Sixty-one percent (n = 1082) responded to the questionnaire and was included for the description of general attitudes towards responsibility for the management of musculoskeletal disorders. For the further analyses of associations to background variables 683–693 individuals could be included. Attitudes were measured by the "Attitudes regarding Responsibility for Musculoskeletal disorders" (ARM) instrument, where responsibility is attributed on four dimensions; to myself, as being out of my hands, to employers or to (medical) professionals. Multiple logistic regression was used to explore associations between attitudes to musculoskeletal disorders and the background variables age, sex, education, physical activity, presence of musculoskeletal disorders, sick leave and whether the person had visited a care provider. Results A majority of participants had internal views, i.e. showed an attitude of taking personal responsibility for musculoskeletal disorders, and did not place responsibility for the management out of their own hands or to employers. However, attributing shared responsibility between self and medical professionals was also found. The main associations found between attitude towards responsibility for musculoskeletal disorders and investigated

  1. Monte Carlo dosimetric study of the Flexisource Co-60 high dose rate source

    PubMed Central

    Granero, Domingo; Perez-Calatayud, Jose; Ballester, Facundo

    2012-01-01

    Purpose Recently, a new HDR 60Co brachytherapy source, Flexisource Co-60, has been developed (Nucletron B.V. Veenendaal, The Netherlands). This study aims to obtain dosimetric data for this source for its use in clinical practice as required by AAPM and ESTRO. Material and methods Two Monte Carlo radiation transport codes were used: Penelope2008 and GEANT4. The source was centrally-positioned in a 100 cm radius water phantom. Absorbed dose and collisional kerma were obtained using 0.01 cm (close) and 0.1 cm (far) sized voxels to provide high-resolution dosimetry near (far from) the source. Dose rate distributions obtained with the two Monte Carlo codes were compared. Results and Discussion Simulations performed with those two radiation transport codes showed an agreement typically within 0.2% for r > 0.8 cm and up to 2% closer to the source. Detailed results of dose distributions are being made available. Conclusions Dosimetric data are provided for the new Flexisource Co-60 source. These data are meant to be used in treatment planning systems in clinical practice. PMID:23346138

  2. [Mathematical simulation support to the dosimetric monitoring on the Russian segment of the International Space Station].

    PubMed

    Mitrikas, V G

    2014-01-01

    To ensure radiation safety of cosmonauts, it is necessary not only to predict, but also to reconstruct absorbed dose dynamics with the knowledge of how long cosmonauts stay in specific space vehicle compartments with different shielding properties and lacking equipment for dosimetric monitoring. In this situation, calculating is one and only way to make a correct estimate of radiation exposure of cosmonaut's organism as a whole (tissue-average dose) and of separate systems and organs. The paper addresses the issues of mathematical simulation of epy radiation environment of standard dosimetric instruments in the Russian segments of the International Space Station (ISS RS). Results of comparing the simulation and experimental data for the complement of dosimeters including ionization chamber-based radiometer R-16, DB8 dosimeters composed of semiconductor detectors, and Pille dosimeters composed of thermoluminescent detectors evidence that the current methods of simulation in support of the ISS RS radiation monitoring provide a sufficiently good agreement between the calculated and experimental data. PMID:25163341

  3. A Dosimetric Analysis of IMRT and Multistatic Fields Techniques for Left Breast Radiotherapy

    SciTech Connect

    Moon, Seong Kwon; Kim, Yeon Sil; Kim, Soo Young; Lee, Mi Jo; Keum, Hyun Sup; Kim, Seung Jin; Youn, Seon Min

    2011-10-01

    The purpose of this study was to analyze the dosimetric difference between intensity-modulated radiation therapy (IMRT) using 3 or 5 beams and multistatic field technique (MSF) in radiotherapy of the left breast. We made comparative analysis of two kinds of radiotherapy that can achieve improved dose homogeneity. First is a MSF that uses both major and small irradiation fields at the same time. The other is IMRT using 3 or 5 beams with an inverse planning system using multiple static multileaf collimators. We made treatment plans for 16 early left breast cancer patients who were randomly selected and had undergone breast conserving surgery and radiotherapy, and analyzed them in the dosimetric aspect. For the mean values of V{sub 95} and dose homogeneity index, no statistically significant difference was observed among the three therapies. Extreme hot spots receiving >110% of prescribed dose were not found in any of the three methods. Using Tukey's test, IMRT showed a significantly larger increase in exposure dose to the ipsilateral lung and the heart than MSF in the low-dose area, but in the high-dose area, MSF showed a slight increase. To improve dose homogeneity, the application of MSF, which can be easily planned and applied more widely, is considered optimal as an alternative to IMRT for radiotherapy of early left breast cancer.

  4. [Mathematical simulation support to the dosimetric monitoring on the Russian segment of the International Space Station].

    PubMed

    Mitrikas, V G

    2014-01-01

    To ensure radiation safety of cosmonauts, it is necessary not only to predict, but also to reconstruct absorbed dose dynamics with the knowledge of how long cosmonauts stay in specific space vehicle compartments with different shielding properties and lacking equipment for dosimetric monitoring. In this situation, calculating is one and only way to make a correct estimate of radiation exposure of cosmonaut's organism as a whole (tissue-average dose) and of separate systems and organs. The paper addresses the issues of mathematical simulation of epy radiation environment of standard dosimetric instruments in the Russian segments of the International Space Station (ISS RS). Results of comparing the simulation and experimental data for the complement of dosimeters including ionization chamber-based radiometer R-16, DB8 dosimeters composed of semiconductor detectors, and Pille dosimeters composed of thermoluminescent detectors evidence that the current methods of simulation in support of the ISS RS radiation monitoring provide a sufficiently good agreement between the calculated and experimental data.

  5. TL dosimetric properties of Li2O-B2O3 glasses for gamma dosimetry.

    PubMed

    El-Adawy, A; Khaled, N E; El-Sersy, A R; Hussein, A; Donya, H

    2010-06-01

    In this work, the thermoluminescence (TL) dosimetric characteristics of lithium borate glasses have been studied in detail before and after doping with silver. The glass specimens were prepared using a conventional melt-quenching method and checked using X-ray diffraction (XRD) pattern. The resultant glow curve of the undoped gamma-irradiated samples showed one strong peak at about 178 degrees C and at a constant heating-rate (beta) of 5 degrees C/s. While, the Ag-doped samples showed two TL glow peaks around 220 and 320 degrees C, which were mainly attributed to the Ag(+) ions. Trap parameters of glow peaks of the present glass systems were extracted. The dosimetric characteristics of glass specimens were read from the TL gamma-dose response curve, which showed a reasonably good linearity behavior between glow peak areas and gamma-dose values. The present results revealed the importance of using such current selective glass structures as gamma-radiation detectors within the studied dose-range where an acceptably good fading response was observed. PMID:20122841

  6. Dosimetric investigations of Tb3+-doped strontium silicate phosphor.

    PubMed

    Barve, R A; Suriyamurthy, N; Panigrahi, B S; Venkatraman, B

    2015-03-01

    Tb(3+)-doped SrSiO(3) phosphor synthesised by co-precipitation technique exhibits intense green emission due to cross-relaxation phenomena between Tb(3+) ions. Dosimetric properties of this phosphor have been investigated using thermoluminescence (TL) technique. A dosimetrically useful glow peak observed was at 581 K along with a linear dose response over the wide dose range (100 mGy-4 Gy). TL parameters such as trap depth (E), frequency factor (s) and the order of kinetics (b) are determined by different methods such as Chen's peak shape, initial rise, isothermal decay and variable heating rate methods. Results of these methods are compared and reported in this study.

  7. Thermoluminescent properties studies of spodumene lilac sample to dosimetric applications

    NASA Astrophysics Data System (ADS)

    Lima, L. L.; Oliveira, R. A. P.; Lima, H. R. B. R.; Santos, H. N.; Santos, J. O.; Lima, A. F.; Souza, S. O.

    2010-11-01

    This work investigates the thermoluminescent (TL) dosimetric properties in natural spodumene, LiAlSi2O6, called kunzite, from Minas Gerais State, Brazil. The mineralogical and chemical composition of this material was identified by means X-ray fluorescence and X-ray diffraction. Some dosimetric properties were studied, such as thermoluminescent emission curves as function of gamma dose. The glow curves of annealed kunzite presented two very intense TL peaks at 215 °C (peak II) and 350 °C (peak III), after gamma irradiation, being both of first kinetic order. These two most prominent peaks analyzed do not presented a linear growth in the range of 50 to 5000 Gy in the range of doses studied. The peak II also presented a very short calculated lifetime, which means it is hardly can be used in dosimetry, while the peak III has a longer lifetime and could be used in some applications for high doses dosimetry.

  8. Retrospective evaluation of dosimetric quality for prostate carcinomas treated with 3D conformal, intensity modulated and volumetric modulated arc radiotherapy

    SciTech Connect

    Crowe, Scott B; Kairn, Tanya; Middlebrook, Nigel; Hill, Brendan; Christie, David R H; Knight, Richard T; Kenny, John; Langton, Christian M; Trapp, Jamie V

    2013-12-15

    This study examines and compares the dosimetric quality of radiotherapy treatment plans for prostate carcinoma across a cohort of 163 patients treated across five centres: 83 treated with three-dimensional conformal radiotherapy (3DCRT), 33 treated with intensity modulated radiotherapy (IMRT) and 47 treated with volumetric modulated arc therapy (VMAT). Treatment plan quality was evaluated in terms of target dose homogeneity and organs at risk (OAR), through the use of a set of dose metrics. These included the mean, maximum and minimum doses; the homogeneity and conformity indices for the target volumes; and a selection of dose coverage values that were relevant to each OAR. Statistical significance was evaluated using two-tailed Welch's T-tests. The Monte Carlo DICOM ToolKit software was adapted to permit the evaluation of dose metrics from DICOM data exported from a commercial radiotherapy treatment planning system. The 3DCRT treatment plans offered greater planning target volume dose homogeneity than the other two treatment modalities. The IMRT and VMAT plans offered greater dose reduction in the OAR: with increased compliance with recommended OAR dose constraints, compared to conventional 3DCRT treatments. When compared to each other, IMRT and VMAT did not provide significantly different treatment plan quality for like-sized tumour volumes. This study indicates that IMRT and VMAT have provided similar dosimetric quality, which is superior to the dosimetric quality achieved with 3DCRT.

  9. Impact of cutout off axis on electron beam dosimetric parameters.

    PubMed

    Arunkumar, T; Supe, S S; Ravikumar, M; Sathiyan, S; Ganesh, K M

    2012-04-01

    Dosimetric changes caused by the positional uncertainty of centering a small electron cutout to the machine central axis (CAX) of the linear accelerator (linac) were investigated. Six circular cutouts with 4 cm diameter were made with their centres shifted off by 0, 2, 4, 6, 8 and 10 mm from the machine CAX. The 6 x 6 cm(2) electron applicator was used for the measurement. The percentage depth doses (PDDs) were measured at the Machine CAX and also with respect to cutout centre for 6, 9, 12, 16 and 20 MeV electron beams. The in-line and cross-line profiles were measured at the depth of maximum dose (R100). The relative output factor (ROF) was measured at the reference depth. All the measurements were made at nominal source to surface distance (100 cm SSD) as well as at extended SSDs (100, 102, 106 and 110 cm). When the cutout centre was shifted away from the machine CAX for low energy beams the depth of 100% dose (R(100)), the depth of 90% dose (R(90)) and the depth of 80% dose (R(80)) had no significant change. For higher energies (>9 MeV) there was a reduction in these dosimetric parameters. The isodose coverage of the in-line and cross-line profile was reduced when the cutout centre was shifted away from the machine CAX. At extended SSDs the dosimetric changes are only because of geometric divergence of the beam and not by the positional uncertainty of the cutout. It is important for the radiation oncologist, dosimetrist, therapist and physicist to note such dosimetric changes while using the electron beam to the patients. PMID:22335408

  10. Dosimetric verification of modulated photon fields by means of compensators for a kernel model.

    PubMed

    Weber, Lars; Laursen, Finn

    2002-01-01

    The approach in treatment planning of applying beam quality correction factors to model compensator-induced depth-hardening effects is investigated and the present work comprises a dosimetric verification of the model for a common compensator material. Lead sheet modulators for four different phantom shapes were designed using a treatment planning system based on the model. The modulators were designed to yield homogeneous dose in a plane. The calculated modulation created by the lead sheets was re-imported into the treatment planning system and applied to a water phantom geometry for verification purposes. Comparing measurements, a total of 31 different geometries were measured, with calculations in this geometry showing good agreement for depth doses, dose profiles and output data with a maximum deviation of 4% except locally in the penumbra region and close to the edges of the cut lead sheets.

  11. The Dosimetric Parameters Investigation of the Pulsed X-ray and Gamma Radiation Sources

    NASA Astrophysics Data System (ADS)

    Stuchebrov, S. G.; Miloichikova, I. A.; Shilova, X. O.

    2016-01-01

    The most common type of radiation used for diagnostic purposes are X-rays. However, X-rays methods have limitations related to the radiation dose for the biological objects. It is known that the use of the pulsed emitting source synchronized with the detection equipment for internal density visualization of objects significant reduces the radiation dose to the object. In the article the analysis of the suitability of the different dosimetric equipment for the radiation dose estimation of the pulsed emitting sources is carried out. The approbation results on the pulsed X-ray generator RAP-160-5 of the dosimetry systems workability with the pulse radiation and its operation range are presented. The results of the dose field investigation of the portable betatron OB-4 are demonstrated. The depth dose distribution in the air, lead and water of the pulsed bremsstrahlung generated by betatron are shown.

  12. Dosimetric differences in flattened and flattening filter-free beam treatment plans

    PubMed Central

    Yan, Yue; Yadav, Poonam; Bassetti, Michael; Du, Kaifang; Saenz, Daniel; Harari, Paul; Paliwal, Bhudatt R.

    2016-01-01

    This study investigated the dosimetric differences in treatment plans from flattened and flattening filter-free (FFF) beams from the TrueBeam System. A total of 104 treatment plans with static (sliding window) intensity-modulated radiotherapy beams and volumetric-modulated arc therapy (VMAT) beams were generated for 15 patients involving three cancer sites. In general, the FFF beam provides similar target coverage as the flattened beam with improved dose sparing to organ-at-risk (OAR). Among all three cancer sites, the head and neck showed more important differences between the flattened beam and FFF beam. The maximum reduction of the FFF beam in the mean dose reached up to 2.82 Gy for larynx in head and neck case. Compared to the 6 MV flattened beam, the 10 MV FFF beam provided improved dose sparing to certain OARs, especially for VMAT cases. Thus, 10 MV FFF beam could be used to improve the treatment plan. PMID:27217620

  13. Dosimetric Characteristics of 6 MV Modified Beams by Physical Wedges of a Siemens Linear Accelerator.

    PubMed

    Zabihzadeh, Mansour; Birgani, Mohammad Javad Tahmasebi; Hoseini-Ghahfarokhi, Mojtaba; Arvandi, Sholeh; Hoseini, Seyed Mohammad; Fadaei, Mahbube

    2016-01-01

    Physical wedges still can be used as missing tissue compensators or filters to alter the shape of isodose curves in a target volume to reach an optimal radiotherapy plan without creating a hotspot. The aim of this study was to investigate the dosimetric properties of physical wedges filters such as off-axis photon fluence, photon spectrum, output factor and half value layer. The photon beam quality of a 6 MV Primus Siemens modified by 150 and 450 physical wedges was studied with BEAMnrc Monte Carlo (MC) code. The calculated present depth dose and dose profile curves for open and wedged photon beam were in good agreement with the measurements. Increase of wedge angle increased the beam hardening and this effect was more pronounced at the heal region. Using such an accurate MC model to determine of wedge factors and implementation of it as a calculation algorithm in the future treatment planning systems is recommended. PMID:27221838

  14. 78 FR 2695 - Privacy Act of 1974; System of Records

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-14

    ... Records Accordingly, for the reasons stated, the Postal Service proposes changes in the existing system of..., Social Security Number, Employee Identification Number, postal assignment information, veteran status... include Social Security Number or Employee Identification Number, name and address of facility where...

  15. 77 FR 46528 - Privacy Act of 1974; System of Records

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-03

    ... to the system manager title update, there is a continuing need to reflect changes in the identity or... records in the Federal Register when there is a revision, change, or addition. The Postal Service TM has... Postal Service made additional management and organizational changes. II. Rationale for Changes to...

  16. SU-E-T-119: Dosimetric and Mechanical Characteristics of Elekta Infinity LINAC with Agility MLC

    SciTech Connect

    Park, J; Xu, Q; Xue, J; Zhai, Y; An, L; Chen, Y

    2014-06-01

    Purpose: Elekta Infinity is the one of the latest generation LINAC with unique features. Two Infinity LINACs are recently commissioned at our institution. The dosimetric and mechanical characteristics of the machines are presented. Methods: Both Infinity LINACs with Agility MLC (160 leaves with 0.5 cm leaf width) are configured with five electron energies (6, 9, 12, 15, and 18 MeV) and two photon energies (6 and 15 MV). One machine has additional photon energy (10 MV). The commissioning was performed by following the manufacturer's specifications and AAPM TG recommendations. Beam data of both electron and photon beams are measured with scanning ion chambers and linear diode array. Machines are adjusted to have the dosimetrically equivalent characteristics. Results: The commissioning of mechanical and imaging system meets the tolerances by TG recommendations. The PDD{sub 10} of various field sizes for 6 and 15 MV shows < 0.5% difference between two machines. For each electron beams, R{sub 80} matches with < 0.4 mm difference. The symmetry and flatness agree within 0.8% and 0.9% differences for photon beams, respectively. For electron beams, the differences of the symmetry and flatness are within 1.2% and 0.8%, respectively. The mean inline penumbras for 6, 10, and 15 MV are respectively 5.1±0.24, 5.6±0.07, and 5.9±0.10 mm for 10x10 cm at 10 cm depth. The crossline penumbras are larger than inline penumbras by 2.2, 1.4, and 1.0 mm, respectively. The MLC transmission factor with interleaf leakage is 0.5 % for all photon energies. Conclusion: The dosimetric and mechanical characteristics of two Infinity LINACs show good agreements between them. Although the Elekta Infinity has been used in many institutions, the detailed characteristics of the machine have not been reported. This study provides invaluable information to understand the Infinity LINAC and to compare the quality of commissioning data for other LINACs.

  17. Dosimetric advantages of IMPT over IMRT for laser-accelerated proton beams

    NASA Astrophysics Data System (ADS)

    Luo, W.; Li, J.; Fourkal, E.; Fan, J.; Xu, X.; Chen, Z.; Jin, L.; Price, R.; Ma, C.-M.

    2008-12-01

    As a clinical application of an exciting scientific breakthrough, a compact and cost-efficient proton therapy unit using high-power laser acceleration is being developed at Fox Chase Cancer Center. The significance of this application depends on whether or not it can yield dosimetric superiority over intensity-modulated radiation therapy (IMRT). The goal of this study is to show how laser-accelerated proton beams with broad energy spreads can be optimally used for proton therapy including intensity-modulated proton therapy (IMPT) and achieve dosimetric superiority over IMRT for prostate cancer. Desired energies and spreads with a varying δE/E were selected with the particle selection device and used to generate spread-out Bragg peaks (SOBPs). Proton plans were generated on an in-house Monte Carlo-based inverse-planning system. Fifteen prostate IMRT plans previously used for patient treatment have been included for comparison. Identical dose prescriptions, beam arrangement and consistent dose constrains were used for IMRT and IMPT plans to show the dosimetric differences that were caused only by the different physical characteristics of proton and photon beams. Different optimization constrains and beam arrangements were also used to find optimal IMPT. The results show that conventional proton therapy (CPT) plans without intensity modulation were not superior to IMRT, but IMPT can generate better proton plans if appropriate beam setup and optimization are used. Compared to IMRT, IMPT can reduce the target dose heterogeneity ((D5-D95)/D95) by up to 56%. The volume receiving 65 Gy and higher (V65) for the bladder and the rectum can be reduced by up to 45% and 88%, respectively, while the volume receiving 40 Gy and higher (V40) for the bladder and the rectum can be reduced by up to 49% and 68%, respectively. IMPT can also reduce the whole body non-target tissue dose by up to 61% or a factor 2.5. This study has shown that the laser accelerator under development has a

  18. Dosimetric comparison between model 9011 and 6711 sources in prostate implants

    SciTech Connect

    Zhang, Hualin; Beyer, David

    2013-07-01

    The purpose of this work is to evaluate the model 9011 iodine-125 ({sup 125}I) in prostate implants by comparing dosimetric coverage provided by the 6711 vs 9011 source implants. Postimplant dosimetry was performed in 18 consecutively implanted patients with prostate cancer. Two were implanted with the 9011 source and 16 with the 6711 source. For purposes of comparison, each implant was then recalculated assuming use of the other source. The same commercially available planning system was used and the specific source data for both 6711 and 9011 products were entered. The results of these calculations are compared side by side in the terms of the isodose values covering 100% (D100) and 90% (D90) of prostate volume, and the percentages of volumes of prostate, bladder, rectum, and urethra covered by 200% (V200), 150% (V150), 100% (V100), 50% (V50), and 20% (V20) of the prescribed dose as well. The 6711 source data overestimate coverage by 6.4% (ranging from 4.9% to 6.9%; median 6.6%) at D100 and by 6.6% (ranging from 6.2% to 6.8%; median 6.6%) at D90 compared with actual 9011 data. Greater discrepancies of up to 67% are seen at higher dose levels: average reduction for V100 is 2.7% (ranging from 0.6% to 7.7%; median 2.3%), for V150 is 14.6% (ranging from 6.1% to 20.5%; median 15.3%), for V200 is 14.9% (ranging from 4.8% to 19.1%; median 16%); similarly seen in bladder, rectal, and urethral coverage. This work demonstrates a clear difference in dosimetric behavior between the 9011 and 6711 sources. Using the 6711 source data for 9011 source implants would create a pronounced error in dose calculation. This study provides evidence that the 9011 source can provide the same dosimetric quality as the 6711 source, if properly used; however, the 6711 source data should not be considered as a surrogate for the 9011 source implants.

  19. Dosimetric Characteristics of a Two-Dimensional Diode Array Detector Irradiated with Passively Scattered Proton Beams

    PubMed Central

    Liengsawangwong, Praimakorn; Sahoo, Nanayan; Ding, Xiaoning; Lii, MingFwu; Gillin, Michale T.; Zhu, Xiaorong Ronald

    2015-01-01

    Purpose: To evaluate the dosimetric characteristics of a two-dimensional (2D) diode array detector irradiated with passively scattered proton beams. Materials and Methods: A diode array detector, MapCHECK (Model 1175, Sun Nuclear, Melbourne, FL, USA) was characterized in passive-scattered proton beams. The relative sensitivity of the diodes and absolute dose calibration were determined using a 250 MeV beam. The pristine Bragg curves (PBCs) measured by MapCHECK diodes were compared with those of an ion chamber using a range shift method. The water-equivalent thickness (WET) of the diode array detector’s intrinsic buildup also was determined. The inverse square dependence, linearity, and other proton dosimetric quantities measured by MapCHECK were also compared with those of the ion chambers. The change in the absolute dose response of the MapCHECK as a function of accumulated radiation dose was used as an indicator of radiation damage to the diodes. 2D dose distribution with and without the compensator were measured and compared with the treatment planning system (TPS) calculations. Results: The WET of the MapCHECK diode’s buildup was determined to be 1.7 cm. The MapCHECK-measured PBC were virtually identical to those measured by a parallel-plate ion chamber for 160, 180, and 250 MeV proton beams. The inverse square results of the MapCHECK were within ±0.4% of the ion chamber results. The linearity of MapCHECK results was within 1% of those from the ion chamber as measured in the range between 10 and 300 MU. All other dosimetric quantities were within 1.3% of the ion chamber results. The 2D dose distributions for non-clinical fields without compensator and the patient treatment fields with the compensator were consistent with the TPS results. The absolute dose response of the MapCHECK was changed by 7.4% after an accumulated dose increased by 170 Gy. Conclusions: The MapCHECK is a convenient and useful tool for 2D dose distribution measurements using passively

  20. Dosimetric evaluation of the interplay effect in respiratory-gated RapidArc radiation therapy

    SciTech Connect

    Riley, Craig; Yang, Yong Li, Tianfang; Zhang, Yongqian; Heron, Dwight E.; Huq, M. Saiful

    2014-01-15

    Purpose: Volumetric modulated arc therapy (VMAT) with gating capability has had increasing adoption in many clinics in the United States. In this new technique, dose rate, gantry rotation speed, and the leaf motion speed of multileaf collimators (MLCs) are modulated dynamically during gated beam delivery to achieve highly conformal dose coverage of the target and normal tissue sparing. Compared with the traditional gated intensity-modulated radiation therapy technique, this complicated beam delivery technique may result in larger dose errors due to the intrafraction tumor motion. The purpose of this work is to evaluate the dosimetric influence of the interplay effect for the respiration-gated VMAT technique (RapidArc, Varian Medical Systems, Palo Alto, CA). Our work consisted of two parts: (1) Investigate the interplay effect for different target residual errors during gated RapidArc delivery using a one-dimensional moving phantom capable of producing stable sinusoidal movement; (2) Evaluate the dosimetric influence in ten clinical patients’ treatment plans using a moving phantom driven with a patient-specific respiratory curve. Methods: For the first part of this study, four plans were created with a spherical target for varying residual motion of 0.25, 0.5, 0.75, and 1.0 cm. Appropriate gating windows were applied for each. The dosimetric effect was evaluated using EDR2 film by comparing the gated delivery with static delivery. For the second part of the project, ten gated lung stereotactic body radiotherapy cases were selected and reoptimized to be delivered by the gated RapidArc technique. These plans were delivered to a phantom, and again the gated treatments were compared to static deliveries by the same methods. Results: For regular sinusoidal motion, the dose delivered to the target was not substantially affected by the gating windows when evaluated with the gamma statistics, suggesting the interplay effect has a small role in respiratory-gated Rapid

  1. The International Postal Network and Other Global Flows as Proxies for National Wellbeing

    PubMed Central

    Rutherford, Alex; Anson, Jose; Luengo-Oroz, Miguel; Mascolo, Cecilia

    2016-01-01

    The digital exhaust left by flows of physical and digital commodities provides a rich measure of the nature, strength and significance of relationships between countries in the global network. With this work, we examine how these traces and the network structure can reveal the socioeconomic profile of different countries. We take into account multiple international networks of physical and digital flows, including the previously unexplored international postal network. By measuring the position of each country in the Trade, Postal, Migration, International Flights, IP and Digital Communications networks, we are able to build proxies for a number of crucial socioeconomic indicators such as GDP per capita and the Human Development Index ranking along with twelve other indicators used as benchmarks of national well-being by the United Nations and other international organisations. In this context, we have also proposed and evaluated a global connectivity degree measure applying multiplex theory across the six networks that accounts for the strength of relationships between countries. We conclude by showing how countries with shared community membership over multiple networks have similar socioeconomic profiles. Combining multiple flow data sources can help understand the forces which drive economic activity on a global level. Such an ability to infer proxy indicators in a context of incomplete information is extremely timely in light of recent discussions on measurement of indicators relevant to the Sustainable Development Goals. PMID:27248142

  2. The International Postal Network and Other Global Flows as Proxies for National Wellbeing.

    PubMed

    Hristova, Desislava; Rutherford, Alex; Anson, Jose; Luengo-Oroz, Miguel; Mascolo, Cecilia

    2016-01-01

    The digital exhaust left by flows of physical and digital commodities provides a rich measure of the nature, strength and significance of relationships between countries in the global network. With this work, we examine how these traces and the network structure can reveal the socioeconomic profile of different countries. We take into account multiple international networks of physical and digital flows, including the previously unexplored international postal network. By measuring the position of each country in the Trade, Postal, Migration, International Flights, IP and Digital Communications networks, we are able to build proxies for a number of crucial socioeconomic indicators such as GDP per capita and the Human Development Index ranking along with twelve other indicators used as benchmarks of national well-being by the United Nations and other international organisations. In this context, we have also proposed and evaluated a global connectivity degree measure applying multiplex theory across the six networks that accounts for the strength of relationships between countries. We conclude by showing how countries with shared community membership over multiple networks have similar socioeconomic profiles. Combining multiple flow data sources can help understand the forces which drive economic activity on a global level. Such an ability to infer proxy indicators in a context of incomplete information is extremely timely in light of recent discussions on measurement of indicators relevant to the Sustainable Development Goals.

  3. The International Postal Network and Other Global Flows as Proxies for National Wellbeing.

    PubMed

    Hristova, Desislava; Rutherford, Alex; Anson, Jose; Luengo-Oroz, Miguel; Mascolo, Cecilia

    2016-01-01

    The digital exhaust left by flows of physical and digital commodities provides a rich measure of the nature, strength and significance of relationships between countries in the global network. With this work, we examine how these traces and the network structure can reveal the socioeconomic profile of different countries. We take into account multiple international networks of physical and digital flows, including the previously unexplored international postal network. By measuring the position of each country in the Trade, Postal, Migration, International Flights, IP and Digital Communications networks, we are able to build proxies for a number of crucial socioeconomic indicators such as GDP per capita and the Human Development Index ranking along with twelve other indicators used as benchmarks of national well-being by the United Nations and other international organisations. In this context, we have also proposed and evaluated a global connectivity degree measure applying multiplex theory across the six networks that accounts for the strength of relationships between countries. We conclude by showing how countries with shared community membership over multiple networks have similar socioeconomic profiles. Combining multiple flow data sources can help understand the forces which drive economic activity on a global level. Such an ability to infer proxy indicators in a context of incomplete information is extremely timely in light of recent discussions on measurement of indicators relevant to the Sustainable Development Goals. PMID:27248142

  4. Dosimetric Comparison of Helical Tomotherapy and Linac-IMRT Treatment Plans for Head and Neck Cancer Patients

    SciTech Connect

    Zhang Xin; Penagaricano, Jose; Moros, Eduardo G.; Corry, Peter M.; Yan Yulong; Ratanatharathorn, Vaneerat

    2010-01-01

    The rapid development and clinical implementation of external beam radiation treatment technologies continues. The existence of various commercially available technologies for intensity-modulated radiation therapy (IMRT) has stimulated interest in exploring the differential potential advantage one may have compared with another. Two such technologies, Hi-Art Helical Tomotherapy (HT) and conventional medical linear accelerator-based IMRT (LIMRT) have been shown to be particularly suitable for the treatment of head and neck cancers. In this study, 23 patients who were diagnosed with stages 3 or 4 head and neck cancers, without evidence of distance metastatic disease, were treated in our clinic. Treatment plans were developed for all patients simultaneously on the HT planning station and on the Pinnacle treatment planning system for step-and-shoot IMRT. Patients were treated only on the HT unit, with the LIMRT plan serving as a backup in case the HT system might not be available. All plans were approved for clinical use by a physician. The prescription was that patients receive at least 95% of the planning target volume (PTV), which is 66 Gy at 2.2 Gy per fraction. Several dosimetric parameters were computed: PTV dose coverage; PTV volume conformity index; the normalized total dose (NTD), where doses were converted to 2 Gy per fraction to organs at risk (OAR); and PTV dose homogeneity. Both planning systems satisfied our clinic's PTV prescription requirements. The results suggest that HT plans had, in general, slightly better dosimetric characteristics, especially regarding PTV dose homogeneity and normal tissue sparing. However, for both techniques, doses to OAR were well below the currently accepted normal tissue tolerances. Consequently, factors other than the dosimetric parameters studied here may have to be considered when making a choice between IMRT techniques.

  5. A survey of IAEA/WHO 60Co TLD postal dose intercomparison exercises during 1985-2003.

    PubMed

    Salman, Ahmad Syed; Mahmood, Khalid; Orfi, Saraj Din

    2005-07-01

    Results of the survey of IAEA/WHO Co postal dose intercomparison exercises in which the Secondary Standard Dosimetry Laboratory participated during the period 1985-2003 are presented. In 14 exercises spread over a period of 19 years, the deviation in therapy dose level measurements of the Secondary Standard Dosimetry Laboratory has never exceeded the International Atomic Energy Agency Dosimetry Laboratory acceptable levels of accuracy. The IAEA/WHO thermoluminescent dosimeter postal dose intercomparison service, the procedure for irradiation of thermoluminescent dosimeters, and the water absorbed dose determination are briefly described.

  6. 77 FR 23396 - Revisions to the Requirements for Authority To Manufacture and Distribute Postage Evidencing Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-19

    ... of the providers of Postage Evidencing Systems (PES) to notify the U.S. Postal Service of any cyber... applies the same standard to cyber attacks against the provider's systems. List of Subjects in 39 CFR Part... comments to the Manager, Payment Technology, U.S. Postal Service, 475 L'Enfant Plaza SW., Room...

  7. Biologic data, models, and dosimetric methods for internal emitters

    SciTech Connect

    Weber, D.A.

    1990-01-01

    The absorbed radiation dose from internal emitters has been and will remain a pivotal factor in assessing risk and therapeutic utility in selecting radiopharmaceuticals for diagnosis and treatment. Although direct measurements of absorbed dose and dose distributions in vivo have been and will continue to be made in limited situations, the measurement of the biodistribution and clearance of radiopharmaceuticals in human subjects and the use of this data is likely to remain the primary means to approach the calculation and estimation of absorbed dose from internal emitters over the next decade. Since several approximations are used in these schema to calculate dose, attention must be given to inspecting and improving the application of this dosimetric method as better techniques are developed to assay body activity and as more experience is gained in applying these schema to calculating absorbed dose. Discussion of the need for considering small scale dosimetry to calculate absorbed dose at the cellular level will be presented in this paper. Other topics include dose estimates for internal emitters, biologic data mathematical models and dosimetric methods employed. 44 refs.

  8. Determination of dosimetric quantities in pediatric abdominal computed tomography scans*

    PubMed Central

    Jornada, Tiago da Silva; da Silva, Teógenes Augusto

    2014-01-01

    Objective Aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL). Materials and methods The study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom. Results No significant difference was observed in the values for weighted air kerma index (CW), but the differences were relevant in values for volumetric air kerma index (CVOL), air kerma-length product (PKL,CT) and effective dose. Conclusion Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, PKL,CT and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans. PMID:25741103

  9. Dosimetric algorithm to reproduce isodose curves obtained from a LINAC.

    PubMed

    Estrada Espinosa, Julio Cesar; Martínez Ovalle, Segundo Agustín; Pereira Benavides, Cinthia Kotzian

    2014-01-01

    In this work isodose curves are obtained by the use of a new dosimetric algorithm using numerical data from percentage depth dose (PDD) and the maximum absorbed dose profile, calculated by Monte Carlo in a 18 MV LINAC. The software allows reproducing the absorbed dose percentage in the whole irradiated volume quickly and with a good approximation. To validate results an 18 MV LINAC with a whole geometry and a water phantom were constructed. On this construction, the distinct simulations were processed by the MCNPX code and then obtained the PDD and profiles for the whole depths of the radiation beam. The results data were used by the code to produce the dose percentages in any point of the irradiated volume. The absorbed dose for any voxel's size was also reproduced at any point of the irradiated volume, even when the voxels are considered to be of a pixel's size. The dosimetric algorithm is able to reproduce the absorbed dose induced by a radiation beam over a water phantom, considering PDD and profiles, whose maximum percent value is in the build-up region. Calculation time for the algorithm is only a few seconds, compared with the days taken when it is carried out by Monte Carlo. PMID:25045398

  10. Dosimetric Algorithm to Reproduce Isodose Curves Obtained from a LINAC

    PubMed Central

    Estrada Espinosa, Julio Cesar; Martínez Ovalle, Segundo Agustín; Pereira Benavides, Cinthia Kotzian

    2014-01-01

    In this work isodose curves are obtained by the use of a new dosimetric algorithm using numerical data from percentage depth dose (PDD) and the maximum absorbed dose profile, calculated by Monte Carlo in a 18 MV LINAC. The software allows reproducing the absorbed dose percentage in the whole irradiated volume quickly and with a good approximation. To validate results an 18 MV LINAC with a whole geometry and a water phantom were constructed. On this construction, the distinct simulations were processed by the MCNPX code and then obtained the PDD and profiles for the whole depths of the radiation beam. The results data were used by the code to produce the dose percentages in any point of the irradiated volume. The absorbed dose for any voxel's size was also reproduced at any point of the irradiated volume, even when the voxels are considered to be of a pixel's size. The dosimetric algorithm is able to reproduce the absorbed dose induced by a radiation beam over a water phantom, considering PDD and profiles, whose maximum percent value is in the build-up region. Calculation time for the algorithm is only a few seconds, compared with the days taken when it is carried out by Monte Carlo. PMID:25045398

  11. SU-E-T-09: A Dosimetric Analysis of Various Clinically Used Bolus Materials

    SciTech Connect

    Stowe, M; Yeager, C; Zhou, F; Hand, C

    2014-06-01

    Purpose: To evaluate the dosimetric effect of various clinically used bolus materials. Methods: Materials investigated include solid water, superflab, wet gauze, wet sheets, Play-Doh{sup ™}, and gauze embedded with petroleum jelly. Each bolusing material was scanned in a Philips CT to determine the Hounsfield unit (HU) and to verify uniformity throughout the material. Using the corresponding HU, boluses of 0.5 cm and 1.0 cm thicknesses were created in the Eclipse treatment planning system (TPS) on a solid water phantom. Dose was calculated at various depths for beam energies 6 MV, 6 MeV, 9 MeV, and 12 MeV to determine the effects of each material on deposition of dose. In addition, linac-based measurements at these energies were made using a farmer chamber in solid water. Wet sheets and wet gauze were measured with various water content to quantify the effects on dose. Results: Preliminary CT scans find a range in HU of bolus materials from −120 to almost 300. There is a trend in the dose at depth based on the HU of the material; however inconsistencies are found when the bolus materials have a negative HU value. The measured data indicates that there is a linear relationship between the mass of water in a material and the dose reading, the slope of which is material dependent. Conclusion: Due to the variation in HU of the bolus materials studied, it is recommended that any new bolus be evaluated before clinical use to determine physical and dosimetric properties. If possible, patients should have bolus included in their CT scans; or if the bolus is created in the TPS, the HU should correspond to the material used. For water-soaked materials, once the bolus material is selected (gauze or sheet), the bolusing effect is only dependent on the amount of water applied to the material.

  12. Dosimetric Quantities for Computed Tomography Examinations of Paediatric Patients on the Thoracic and Abdominal Regions

    SciTech Connect

    Flores-M, E.; Gamboa de Buen, I.; Buenfil, A. E.; Ruiz-Trejo, C.; Dies, P.

    2010-12-07

    Computed Tomography (CT) is a high dose X ray imaging procedure and its use has rapidly increased in the last two decades fueled by the development of helical CT. The aim of this study is to present values of the dosimetric quantities for CT paediatric examinations of thoracic and abdominal regions. The protocols studied were those of chest, lung-mediastine, chest-abdomen, pulmonary high resolution and mediastine-abdomen, which are the more common examinations performed at ''Hospital Infantil de Mexico Federico Gomez'' in the thoracic-abdominal region. The measurements were performed on a Siemens SOMATOM Sensation 16 CT Scanner and the equipment used was a CT pencil ionization chamber, connected to an electrometer. This system was calibrated for RQT9 CT beam quality. A PMMA head phantom with diameter of 16 cm and length of 15 cm was also used. The dosimetric quantities measured were the weighted air kerma index (C{sub w}), the volumetric dose index (C{sub vol}) and the CT air kerma-length product. It was found that the pulmonary high resolution examination presented the highest values for the C{sub w}(31.1 mGy) and C{sub vol}(11.1 mGy). The examination with the lowest values of these two quantities was the chest-abdomen protocol with 10.5 mGy for C{sub w} and 5.5 mGy for C{sub vol}. However, this protocol presented the highest value for P{sub KL,CT}(282.2 mGy cm) when considering the average clinical length of the examinations.

  13. SU-E-J-167: Dosimetric Consequences From Minimal Displacements in APBI with SAVI Applicators

    SciTech Connect

    Chandrasekara, S; Dumitru, N; Hyvarinen, M; Pella, S

    2015-06-15

    Purpose: To determine the importance of providing proper solid immobilization in every fraction of treatment in APBI with brachytherapy. Methods: 125 patients treated with APBI brachytherapy with SAVI applicators at SFRO Boca Raton, from 2013–2015 were considered for this retrospective study. The CT scans of each patient, which were taken before each treatment, were imported in to the Oncentra treatment planning system. Then they were compared with the initial CT scan which was used for the initial plan. Deviation in displacements in reference to ribs and skin surface was measured and dosimetric evaluations respective to the initial image were performed. Results: Small deviations in displacements were observed from the SAVI applicator to the ribs and the skin surface. Dosimetric evaluations revealed, very small changes in the inter-fractionation position make significant differences in the maximum dose to critical organs. Additionally, the volume of the cavity also changed between fractions. As a Result, the maximum dose manifested variance between 10% and 32% in ribs and skin surface respectively. Conclusion: It appears that taking a CT scan before each treatment is necessary to minimize the risk of delivering undesired high doses to the critical organs. This study indicates, in 30% of the cases re-planning was necessary between treatments. We conclude that, treatment planning teams should evaluate the placement of the device by analyzing the CT images before each treatment and they must be prepared for re-planning if needed. This study also reveals the urgent need of improving the immobilization methods with APBI when treating with the SAVI applicator.

  14. Conventional Versus Automated Implantation of Loose Seeds in Prostate Brachytherapy: Analysis of Dosimetric and Clinical Results

    SciTech Connect

    Genebes, Caroline; Filleron, Thomas; Graff, Pierre; Jonca, Frédéric; Huyghe, Eric; Thoulouzan, Matthieu; Soulie, Michel; Malavaud, Bernard; Aziza, Richard; Brun, Thomas; Delannes, Martine; Bachaud, Jean-Marc

    2013-11-15

    Purpose: To review the clinical outcome of I-125 permanent prostate brachytherapy (PPB) for low-risk and intermediate-risk prostate cancer and to compare 2 techniques of loose-seed implantation. Methods and Materials: 574 consecutive patients underwent I-125 PPB for low-risk and intermediate-risk prostate cancer between 2000 and 2008. Two successive techniques were used: conventional implantation from 2000 to 2004 and automated implantation (Nucletron, FIRST system) from 2004 to 2008. Dosimetric and biochemical recurrence-free (bNED) survival results were reported and compared for the 2 techniques. Univariate and multivariate analysis researched independent predictors for bNED survival. Results: 419 (73%) and 155 (27%) patients with low-risk and intermediate-risk disease, respectively, were treated (median follow-up time, 69.3 months). The 60-month bNED survival rates were 95.2% and 85.7%, respectively, for patients with low-risk and intermediate-risk disease (P=.04). In univariate analysis, patients treated with automated implantation had worse bNED survival rates than did those treated with conventional implantation (P<.0001). By day 30, patients treated with automated implantation showed lower values of dose delivered to 90% of prostate volume (D90) and volume of prostate receiving 100% of prescribed dose (V100). In multivariate analysis, implantation technique, Gleason score, and V100 on day 30 were independent predictors of recurrence-free status. Grade 3 urethritis and urinary incontinence were observed in 2.6% and 1.6% of the cohort, respectively, with no significant differences between the 2 techniques. No grade 3 proctitis was observed. Conclusion: Satisfactory 60-month bNED survival rates (93.1%) and acceptable toxicity (grade 3 urethritis <3%) were achieved by loose-seed implantation. Automated implantation was associated with worse dosimetric and bNED survival outcomes.

  15. Effect of heterogeneity correction on dosimetric parameters of radiotherapy planning for thoracic esophageal cancer

    SciTech Connect

    Nakayama, Masao; Yoshida, Kenji; Nishimura, Hideki; Miyawaki, Daisuke; Uehara, Kazuyuki; Okamoto, Yoshiaki; Okayama, Takanobu; Sasaki, Ryohei

    2014-04-01

    The present study aimed to investigate the effect of heterogeneity correction (HC) on dosimetric parameters in 3-dimensional conformal radiotherapy planning for patients with thoracic esophageal cancer. We retrospectively analyzed 20 patients. Two treatment plans were generated for each patient using a superposition algorithm on the Xio radiotherapy planning system. The first plan was calculated without HC. The second was a new plan calculated with HC, using identical beam geometries and maintaining the same number of monitor units as the first. With regard to the planning target volume (PTV), the overall mean differences in the prescription dose, maximum dose, mean dose, and dose that covers 95% of the PTV between the first and second plans were 1.10 Gy (1.8%), 1.35 Gy (2.2%), 1.10 Gy (1.9%), and 0.56 Gy (1.0%), respectively. With regard to parameters related to the organs at risk (OARs), the mean differences in the absolute percentages of lung volume receiving greater than 5, 10, 20, and 30 Gy (lung V{sub 5}, V{sub 10}, V{sub 20}, and V{sub 30}) between the first and second plans were 7.1%, 2.7%, 0.4%, and 0.5%, respectively. These results suggest that HC might have a more pronounced effect on the percentages of lung volume receiving lower doses (e.g., V{sub 5} and V{sub 10}) than on the dosimetric parameters related to the PTV and other OARs.

  16. Dosimetric uncertainty in prostate cancer proton radiotherapy

    SciTech Connect

    Lin Liyong; Vargas, Carlos; Hsi Wen; Indelicato, Daniel; Slopsema, Roelf; Li Zuofeng; Yeung, Daniel; Horne, Dave; Palta, Jatinder

    2008-11-15

    Purpose: The authors we evaluate the uncertainty in proton therapy dose distribution for prostate cancer due to organ displacement, varying penumbra width of proton beams, and the amount of rectal gas inside the rectum. Methods and Materials: Proton beam treatment plans were generated for ten prostate patients with a minimum dose of 74.1 cobalt gray equivalent (CGE) to the planning target volume (PTV) while 95% of the PTV received 78 CGE. Two lateral or lateral oblique proton beams were used for each plan. The authors we investigated the uncertainty in dose to the rectal wall (RW) and the bladder wall (BW) due to organ displacement by comparing the dose-volume histograms (DVH) calculated with the original or shifted contours. The variation between DVHs was also evaluated for patients with and without rectal gas in the rectum for five patients who had 16 to 47 cc of visible rectal gas in their planning computed tomography (CT) imaging set. The uncertainty due to the varying penumbra width of the delivered protons for different beam setting options on the proton delivery system was also evaluated. Results: For a 5 mm anterior shift, the relative change in the RW volume receiving 70 CGE dose (V{sub 70}) was 37.9% (5.0% absolute change in 13.2% of a mean V{sub 70}). The relative change in the BW volume receiving 70 CGE dose (V{sub 70}) was 20.9% (4.3% absolute change in 20.6% of a mean V{sub 70}) with a 5 mm inferior shift. A 2 mm penumbra difference in beam setting options on the proton delivery system resulted in the relative variations of 6.1% (0.8% absolute change) and 4.4% (0.9% absolute change) in V{sub 70} of RW and BW, respectively. The data show that the organ displacements produce absolute DVH changes that generally shift the entire isodose line while maintaining the same shape. The overall shape of the DVH curve for each organ is determined by the penumbra and the distance of the target in beam's eye view (BEV) from the block edge. The beam setting option

  17. Contura Multi-Lumen Balloon Breast Brachytherapy Catheter: Comparative Dosimetric Findings of a Phase 4 Trial

    SciTech Connect

    Arthur, Douglas W.; Vicini, Frank A.; Julian, Thomas B.; Cuttino, Laurie W.; Mukhopadhyay, Nitai D.

    2013-06-01

    Purpose: Final dosimetric findings of a completed, multi-institutional phase 4 registry trial using the Contura Multi-Lumen Balloon (MLB) breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer are presented. Methods and Materials: Three dosimetric plans with identical target coverage were generated for each patient for comparison: multilumen multidwell (MLMD); central-lumen multidwell (CLMD); and central-lumen single-dwell (CLSD) loading of the Contura catheter. For this study, a successful treatment plan achieved ideal dosimetric goals and included the following: ≥95% of the prescribed dose (PD) covering ≥95% of the target volume (TV); maximum skin dose ≤125% of the PD; maximum rib dose ≤145% of the PD; and V150 ≤50 cc and V200 ≤10 cc. Results: Between January 2008 and February 2011, 23 institutions participated. A total of 318 patients were available for dosimetric review. Using the Contura MLB, all dosimetric criteria were met in 78.93% of cases planned with MLMD versus 55.38% with the CLMD versus 37.66% with the CLSD (P≤.0001). Evaluating all patients with the full range of skin to balloon distance represented, median maximum skin dose was reduced by 12% and median maximum rib dose by 13.9% when using MLMD-based dosimetric plans compared to CLSD. The dosimetric benefit of MLMD was further demonstrated in the subgroup of patients where skin thickness was <5 mm, where MLMD use allowed a 38% reduction in median maximum skin dose over CLSD. For patients with rib distance <5 mm, the median maximum rib dose reduction was 27%. Conclusions: Use of the Contura MLB catheter produced statistically significant improvements in dosimetric capabilities between CLSD and CLMD treatments. This device approach demonstrates the ability not only to overcome the barriers of limited skin thickness and close rib proximity, but to consistently achieve a higher standard of dosimetric planning goals.

  18. Analysis of superficial fluorescence patterns in nonmelanoma skin cancer during photodynamic therapy by a dosimetric model

    NASA Astrophysics Data System (ADS)

    Salas-García, I.; Fanjul-Vélez, F.; Arce-Diego, J. L.

    2016-03-01

    In this work the superficial fluorescence patterns in different nonmelanoma skin cancers and their photodynamic treatment response are analysed by a fluorescence based dosimetric model. Results show differences of even more than 50% in the fluorescence patterns as photodynamic therapy progresses depending on the malignant tissue type. They demonstrate the great relevance of the biological media as an additional dosimetric factor and contribute to the development of a future customized therapy with the assistance of dosimetric tools to interpret the fluorescence images obtained during the treatment monitoring and the differential photodiagnosis.

  19. TH-E-BRE-05: Analysis of Dosimetric Characteristics in Two Leaf Motion Calculator Algorithms for Sliding Window IMRT

    SciTech Connect

    Wu, L; Huang, B; Rowedder, B; Ma, B; Kuang, Y

    2014-06-15

    Purpose: The Smart leaf motion calculator (SLMC) in Eclipse treatment planning system is an advanced fluence delivery modeling algorithm as it takes into account fine MLC features including inter-leaf leakage, rounded leaf tips, non-uniform leaf thickness, and the spindle cavity etc. In this study, SLMC and traditional Varian LMC (VLMC) algorithms were investigated, for the first time, in dosimetric characteristics and delivery accuracy of sliding window (SW) IMRT. Methods: The SW IMRT plans of 51 cancer cases were included to evaluate dosimetric characteristics and dose delivery accuracy from leaf motion calculated by SLMC and VLMC, respectively. All plans were delivered using a Varian TrueBeam Linac. The DVH and MUs of the plans were analyzed. Three patient specific QA tools - independent dose calculation software IMSure, Delta4 phantom, and EPID portal dosimetry were also used to measure the delivered dose distribution. Results: Significant differences in the MUs were observed between the two LMCs (p≤0.001).Gamma analysis shows an excellent agreement between the planned dose distribution calculated by both LMC algorithms and delivered dose distribution measured by three QA tools in all plans at 3%/3 mm, leading to a mean pass rate exceeding 97%. The mean fraction of pixels with gamma < 1 of SLMC is slightly lower than that of VLMC in the IMSure and Delta4 results, but higher in portal dosimetry (the highest spatial resolution), especially in complex cases such as nasopharynx. Conclusion: The study suggests that the two LMCs generates the similar target coverage and sparing patterns of critical structures. However, SLMC is modestly more accurate than VLMC in modeling advanced MLC features, which may lead to a more accurate dose delivery in SW IMRT. Current clinical QA tools might not be specific enough to differentiate the dosimetric discrepancies at the millimeter level calculated by these two LMC algorithms. NIH/NIGMS grant U54 GM104944, Lincy Endowed

  20. Dosimetric comparison of split field and fixed jaw techniques for large IMRT target volumes in the head and neck.

    PubMed

    Srivastava, Shiv P; Das, Indra J; Kumar, Arvind; Johnstone, Peter A S

    2011-01-01

    Some treatment planning systems (TPSs), when used for large-field (>14 cm) intensity-modulated radiation therapy (IMRT), create split fields that produce excessive multiple-leaf collimator segments, match-line dose inhomogeneity, and higher treatment times than nonsplit fields. A new method using a fixed-jaw technique (FJT) forces the jaw to stay at a fixed position during optimization and is proposed to reduce problems associated with split fields. Dosimetric comparisons between split-field technique (SFT) and FJT used for IMRT treatment is presented. Five patients with head and neck malignancies and regional target volumes were studied and compared with both techniques. Treatment planning was performed on an Eclipse TPS using beam data generated for Varian 2100C linear accelerator. A standard beam arrangement consisting of nine coplanar fields, equally spaced, was used in both techniques. Institutional dose-volume constraints used in head and neck cancer were kept the same for both techniques. The dosimetric coverage for the target volumes between SFT and FJT for head and neck IMRT plan is identical within ± 1% up to 90% dose. Similarly, the organs at risk (OARs) have dose-volume coverage nearly identical for all patients. When the total monitor unit (MU) and segments were analyzed, SFT produces statistically significant higher segments (17.3 ± 6.3%) and higher MU (13.7 ± 4.4%) than the FJT. There is no match line in FJT and hence dose uniformity in the target volume is superior to the SFT. Dosimetrically, SFT and FJT are similar for dose-volume coverage; however, the FJT method provides better logistics, lower MU, shorter treatment time, and better dose uniformity. The number of segments and MU also has been correlated with the whole body radiation dose with long-term complications. Thus, FJT should be the preferred option over SFT for large target volumes.

  1. Dosimetric Comparison of Split Field and Fixed Jaw Techniques for Large IMRT Target Volumes in the Head and Neck

    SciTech Connect

    Srivastava, Shiv P.; Das, Indra J.; Kumar, Arvind; Johnstone, Peter A.S.

    2011-04-01

    Some treatment planning systems (TPSs), when used for large-field (>14 cm) intensity-modulated radiation therapy (IMRT), create split fields that produce excessive multiple-leaf collimator segments, match-line dose inhomogeneity, and higher treatment times than nonsplit fields. A new method using a fixed-jaw technique (FJT) forces the jaw to stay at a fixed position during optimization and is proposed to reduce problems associated with split fields. Dosimetric comparisons between split-field technique (SFT) and FJT used for IMRT treatment is presented. Five patients with head and neck malignancies and regional target volumes were studied and compared with both techniques. Treatment planning was performed on an Eclipse TPS using beam data generated for Varian 2100C linear accelerator. A standard beam arrangement consisting of nine coplanar fields, equally spaced, was used in both techniques. Institutional dose-volume constraints used in head and neck cancer were kept the same for both techniques. The dosimetric coverage for the target volumes between SFT and FJT for head and neck IMRT plan is identical within {+-}1% up to 90% dose. Similarly, the organs at risk (OARs) have dose-volume coverage nearly identical for all patients. When the total monitor unit (MU) and segments were analyzed, SFT produces statistically significant higher segments (17.3 {+-} 6.3%) and higher MU (13.7 {+-} 4.4%) than the FJT. There is no match line in FJT and hence dose uniformity in the target volume is superior to the SFT. Dosimetrically, SFT and FJT are similar for dose-volume coverage; however, the FJT method provides better logistics, lower MU, shorter treatment time, and better dose uniformity. The number of segments and MU also has been correlated with the whole body radiation dose with long-term complications. Thus, FJT should be the preferred option over SFT for large target volumes.

  2. Correlation of dosimetric parameters obtained with the analytical anisotropic algorithm and toxicity of chest chemoradiation in lung carcinoma

    SciTech Connect

    Cartier, Lysian; Auberdiac, Pierre; Khodri, Mustapha; Malkoun, Nadia; Chargari, Cyrus; Thorin, Julie; Melis, Adrien; Talabard, Jean-Noeel; Laroche, Guy de; Fournel, Pierre; Tiffet, Olivier; Schmitt, Thierry; and others

    2012-07-01

    The purpose of this study was to analyze and revisit toxicity related to chest chemoradiotherapy and to correlate these side effects with dosimetric parameters obtained using analytical anisotropic algorithm (AAA) in locally unresectable advanced lung cancer. We retrospectively analyzed data from 47 lung cancer patients between 2005 and 2008. All received conformal 3D radiotherapy using high-energy linear accelerator plus concomitant chemotherapy. All treatment planning data were transferred into Eclipse 8.05 (Varian Medical Systems, Palo Alto, CA) and dosimetric calculations were performed using AAA. Thirty-three patients (70.2%) developed acute pneumopathy after radiotherapy (grades 1 and 2). One patient (2.1%) presented with grade 3 pneumopathy. Thirty-one (66%) presented with grades 1-2 lung fibrosis, and 1 patient presented with grade 3 lung fibrosis. Thirty-four patients (72.3%) developed grade 1-2 acute oesophagic toxicity. Four patients (8.5%) presented with grades 3 and 4 dysphagia, necessitating prolonged parenteral nutrition. Median prescribed dose was 64 Gy (range 50-74) with conventional fractionation (2 Gy per fraction). Dose-volume constraints were respected with a median V20 of 23.5% (maximum 34%) and a median V30 of 17% (maximum 25%). The median dose delivered to healthy contralateral lung was 13.1 Gy (maximum 18.1 Gy). At univariate analysis, larger planning target volume and V20 were significantly associated with the probability of grade {>=}2 radiation-induced pneumopathy (p = 0.022 and p = 0.017, respectively). No relation between oesophagic toxicity and clinical/dosimetric parameters could be established. Using AAA, the present results confirm the predictive value of the V20 for lung toxicity as already demonstrated with the conventional pencil beam convolution approach.

  3. 39 CFR 111.3 - Amendments to the Mailing Standards of the United States Postal Service, Domestic Mail Manual.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Amendments to the Mailing Standards of the United... of CFR Sections affected at the end of this volume. Transmittal letter for issue Dated Federal... 48437. 26 April 3, 1988 53 FR 18557. 27 June 19, 1988 53 FR 21821. 28 Sept. 18, 1988 53 FR 35315. 29...

  4. 39 CFR 254.1 - Adoption of U.S. Access Board Standards as Postal Service Standards of Facility Accessibility.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Barriers Act (ABA) “Standards for Facility Accessibility,” the following sections of 36 CFR part 1191... THE ARCHITECTURAL BARRIERS ACT § 254.1 Adoption of U.S. Access Board Standards as Postal Service... Barriers Act, Scoping (which contains ABA Chapter 1, Application and Administration, and ABA Chapter...

  5. 39 CFR 3050.11 - Proposals to change an accepted analytical principle applied in the Postal Service's annual...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) To improve the quality, accuracy, or completeness of the data or analysis of data contained in the... include the data, analysis, and documentation on which the proposal is based, and, where feasible, include... the petitioner requests access to data from the Postal Service to support the assertions...

  6. Dosimetric and geometric evaluation of a novel stereotactic radiotherapy device for breast cancer: The GammaPod Trade-Mark-Sign

    SciTech Connect

    Mutaf, Yildirim D.; Yi, Byong Yong; Prado, Karl; D'Souza, Warren D.; Regine, William F.; Feigenberg, Steven J.; Zhang Jin; Yu, Cedric X.

    2013-04-15

    Purpose: A dedicated stereotactic gamma irradiation device, the GammaPod Trade-Mark-Sign from Xcision Medical Systems, was developed specifically to treat small breast cancers. This study presents the first evaluation of dosimetric and geometric characteristics from the initial prototype installed at University of Maryland Radiation Oncology Department. Methods: The GammaPod Trade-Mark-Sign stereotactic radiotherapy device is an assembly of a hemi-spherical source carrier containing 36 {sup 60}Co sources, a tungsten collimator, a dynamically controlled patient support table, and the breast immobilization system which also functions as a stereotactic frame. The source carrier contains the sources in six columns spaced longitudinally at 60 Degree-Sign intervals and it rotates together with the variable-size collimator to form 36 noncoplanar, concentric arcs focused at the isocenter. The patient support table enables motion in three dimensions to position the patient tumor at the focal point of the irradiation. The table moves continuously in three cardinal dimensions during treatment to provide dynamic shaping of the dose distribution. The breast is immobilized using a breast cup applying a small negative pressure, where the immobilization cup is embedded with fiducials also functioning as the stereotactic frame for the breast. Geometric and dosimetric evaluations of the system as well as a protocol for absorbed dose calibration are provided. Dosimetric verifications of dynamically delivered patient plans are performed for seven patients using radiochromic films in hypothetical preop, postop, and target-in-target treatment scenarios. Results: Loaded with 36 {sup 60}Co sources with cumulative activity of 4320 Ci, the prototype GammaPod Trade-Mark-Sign unit delivers 5.31 Gy/min at the isocenter using the largest 2.5 cm diameter collimator. Due to the noncoplanar beam arrangement and dynamic dose shaping features, the GammaPod Trade-Mark-Sign device is found to deliver

  7. Dosimetric characterization of the M-15 high-dose-rate Iridium-192 brachytherapy source using the AAPM and ESTRO formalism.

    PubMed

    Ho Than, Minh-Tri; Munro Iii, John J; Medich, David C

    2015-05-08

    The Source Production & Equipment Co. (SPEC) model M-15 is a new Iridium-192 brachytherapy source model intended for use as a temporary high-dose-rate (HDR) brachytherapy source for the Nucletron microSelectron Classic afterloading system. The purpose of this study is to characterize this HDR source for clinical application by obtaining a complete set of Monte Carlo calculated dosimetric parameters for the M-15, as recommended by AAPM and ESTRO, for isotopes with average energies greater than 50 keV. This was accomplished by using the MCNP6 Monte Carlo code to simulate the resulting source dosimetry at various points within a pseudoinfinite water phantom. These dosimetric values next were converted into the AAPM and ESTRO dosimetry parameters and the respective statistical uncertainty in each parameter also calculated and presented. The M-15 source was modeled in an MCNP6 Monte Carlo environment using the physical source specifications provided by the manufacturer. Iridium-192 photons were uniformly generated inside the iridium core of the model M-15 with photon and secondary electron transport replicated using photoatomic cross-sectional tables supplied with MCNP6. Simulations were performed for both water and air/vacuum computer models with a total of 4 × 109 sources photon history for each simulation and the in-air photon spectrum filtered to remove low-energy photons belowδ = 10 keV. Dosimetric data, including D·(r,θ), gL(r), F(r,θ), φan(r), and φ-an, and their statistical uncertainty were calculated from the output of an MCNP model consisting of an M-15 source placed at the center of a spherical water phantom of 100 cm diameter. The air kerma strength in free space, SK, and dose rate constant, Λ, also was computed from a MCNP model with M-15 Iridium-192 source, was centered at the origin of an evacuated phantom in which a critical volume containing air at STP was added 100 cm from the source center. The reference dose rate, D·(r0,θ0) ≡ D· (1cm

  8. Telephone reminders are a cost effective way to improve responses in postal health surveys

    PubMed Central

    Salim, S; Smith, W; Bammer, G

    2002-01-01

    Study objective: To assess the effectiveness of a telephone reminder in increasing responses to postal surveys and to calculate the differential costs per completed questionnaire. Design: Randomised controlled trial. Setting: Australian university and rehabilitation medicine practice. Participants: The trial was conducted in 1999 among the 143 non-respondents to a questionnaire about work related neck and upper body disorders. The questionnaire was sent to two Australian female samples: 200 office workers (Sample A) and 92 former rehabilitation medicine patients (Sample B). A reminder letter, another copy of the questionnaire and a final letter were sent at two week intervals. Half of the non-respondents within each sample were randomly selected to receive a telephone reminder just after the second mailout of the questionnaire. All direct costs were calculated. Main results: Responses were significantly higher among those who received the telephone reminder intervention (relative risk 2.54, 95% confidence intervals 1.43 to 4.52). Analysed by intention to phone, 47% of non-respondents in Sample A and 38% in Sample B returned a complete questionnaire after the intervention, compared with 21% and 10%, respectively, in the control groups. For the 112 women (combined samples) who returned completed questionnaires before randomisation, the average cost per respondent was AUD14. There was a higher total cost for the intervention groups (AUD851 versus AUD386 for controls), but the significantly higher number of additional completed responses (31 versus 12) resulted in a 15% lower marginal cost per completed questionnaire in those groups. Conclusion: Telephone reminders are cost effective in improving responses to postal surveys. PMID:11812810

  9. Postal urine specimens: are they a feasible method for genital chlamydial infection screening?

    PubMed Central

    Macleod, J; Rowsell, R; Horner, P; Crowley, T; Caul, E O; Low, N; Smith, G D

    1999-01-01

    BACKGROUND: A United Kingdom (UK) screening programme for Chlamydia trachomatis has recently been announced. Pilot projects involving the opportunistic testing of women attending health facilities are due to commence in several sites. There is a danger that this approach will fail to obtain adequate population coverage. The alternative--true systematic population screening--is generally assumed to be unfeasible. Studies in Denmark using postal urine specimens have challenged this assumption. No such studies have been reported from the UK. AIM: To assess the potential of urine specimens sent by post as the basis for a UK population screening strategy for genital chlamydial infection. METHOD: Two hundred patients (100 men, 100 women) aged 18 to 45 years were randomly sampled from the list of one urban group practice. Subjects were mailed an explanatory letter, a urine sample container, a sexual lifestyle questionnaire, and a prepaid return envelope. Non-responders were contacted by telephone; persistent non-responders were visited at home. Samples were tested for Chlamydia by DNA amplification and enzyme immunoassay. RESULTS: Sixty-four (32%) subjects were no longer living at their GP registered address. Of the remaining 136, 126 (93%) responded to the survey and 113 (83%) accepted the request for a urine sample and completed a questionnaire. Acceptance rates were similar for men and women and across age groups. Four samples (3%) were Chlamydia positive. CONCLUSION: Home mailed urine specimen collection in conjunction with a self-completed postal questionnaire is feasible. This could provide a viable basis both for determining population Chlamydia prevalence and for a UK Chlamydia population screening strategy. Overall cost effectiveness of such a strategy will depend on the cost of the test used. Comparative performance characteristics of the different currently available tests in this setting have yet to be fully determined. PMID:10562745

  10. EFFECTIVE DOSIMETRIC HALF LIFE OF CESIUM 137 SOIL CONTAMINATION

    SciTech Connect

    Jannik, T; P Fledderman, P; Michael Paller, M

    2008-01-09

    In the early 1960s, an area of privately-owned swamp adjacent to the US Department of Energy's Savannah River Site (SRS), known as Creek Plantation, was contaminated by site operations. Studies conducted in 1974 estimated that approximately 925 GBq of {sup 137}Cs was deposited in the swamp. Subsequently, a series of surveys--composed of 52 monitoring locations--was initiated to characterize and trend the contaminated environment. The annual, potential, maximum doses to a hypothetical hunter were estimated by conservatively using the maximum {sup 137}Cs concentrations measured in the soil. The purpose of this report is to calculate an 'effective dosimetric' half-life for {sup 137}Cs in soil (based on the maximum concentrations) and compare it to the effective environmental half-life (based on the geometric mean concentrations).

  11. Bremsstrahlung dosimetric parameters of beta-emitting therapeutic radionuclides

    NASA Astrophysics Data System (ADS)

    Manjunatha, H. C.

    2016-03-01

    Dosimetric parameters such as efficiency of bremsstrahlung, probability of energy loss of beta during bremsstrahlung production, intensity and dose rate of high, medium and low-energy beta-emitting therapeutic radionuclides in different tissues of human organs are computed. These parameters are lower in adipose tissue than all other studied tissues. The efficiency, intensity and dose rate of bremsstrahlung increases with maximum energy of the beta nuclide (Emax) and modified atomic number (Zmod) of the target tissue. The estimated bremsstrahlung efficiency, intensity and dose rate are useful in the calculations of photon track-length distributions. These parameters are useful to determine the quality and quantity of the bremsstrahlung radiation (known as the source term). Precise estimation of this source term is very important in planning for radiotherapy and diagnosis.

  12. Dosimetric comparison of two arc-based stereotactic body radiotherapy techniques for early-stage lung cancer

    SciTech Connect

    Liu, Huan Ye, Jingjing; Kim, John J.; Deng, Jun; Kaur, Monica S.; Chen, Zhe

    2015-04-01

    To compare the dosimetric and delivery characteristics of two arc-based stereotactic body radiotherapy (SBRT) techniques for early-stage lung cancer treatment. SBRT treatment plans for lung tumors of different sizes and locations were designed using a single-isocenter multisegment dynamic conformal arc technique (SiMs-arc) and a volumetric modulated arc therapy technique (RapidArc) for 5 representative patients treated previously with lung SBRT. The SiMs-arc plans were generated with the isocenter located in the geometric center of patient's axial plane (which allows for collision-free gantry rotation around the patient) and 6 contiguous 60° arc segments spanning from 1° to 359°. 2 RapidArc plans, one using the same arc geometry as the SiMs-arc and the other using typical partial arcs (210°) with the isocenter inside planning target volume (PTV), were generated for each corresponding SiMs-arc plan. All plans were generated using the Varian Eclipse treatment planning system (V10.0) and were normalized with PTV V{sub 100} to 95%. PTV coverage, dose to organs at risk, and total monitor units (MUs) were then compared and analyzed. For PTV coverage, the RapidArc plans generally produced higher PTV D{sub 99} (by 1.0% to 3.3%) and higher minimum dose (by 2.7% to 12.7%), better PTV conformality index (by 1% to 8%), and less volume of 50% dose outside 2 cm from PTV (by 0 to 20.8 cm{sup 3}) than the corresponding SiMs-arc plans. For normal tissues, no significant dose differences were observed for the lungs, trachea, chest wall, and heart; RapidArc using partial arcs produced lowest maximum dose to spinal cord. For dose delivery, the RapidArc plans typically required 50% to 90% more MUs than SiMs-arc plans to deliver the same prescribed dose. The additional intensity modulation afforded by variable gantry speed and dose rate and by overlapping arcs enabled RapidArc plans to produce dosimetrically improved plans for lung SBRT, but required more MUs (by a factor > 1.5) to

  13. Adaptive radiotherapy in lung cancer: dosimetric benefits and clinical outcome

    PubMed Central

    Kataria, T; Bisht, S S; Goyal, S; Pushpan, L; Abhishek, A; Govardhan, HB; Kumar, V; Sharma, K; Jain, S; Basu, T; Srivastava, A

    2014-01-01

    Objective: Anatomical changes during radiotherapy (RT) might introduce discrepancies between planned and delivered doses. This study evaluates the need for adaptive treatment in lung cancer RT. Methods: 15 patients with non-small-cell lung cancer, undergoing radical RT with or without concurrent chemotherapy, consecutively underwent planning CT scans at baseline and after 44–46 Gy. Target volumes were delineated on both scans. Phase I delivered 44–46 Gy to the initial planning target volume (PTV). Two Phase II plans for 16–20 Gy were developed on initial and mid-treatment scans, the treatment being delivered with the mid-treatment plan. The second CT structure set was fused with the initial scan data set using dose wash. Volumetric and dosimetric changes in target volumes and critical structures were assessed. Results: There was significant reduction in primary gross tumour volume (34.00%; p = 0.02) and PTV (34.70%; p < 0.01) in the second scan. In Plan 2, delivering the same dose to the initial PTV would have resulted in a significantly higher dose to the lung PTV (V20, 52.18%; V5, 21.76%; mean, 23.93%), contralateral lung (mean, 29.43%), heart (V10, 81.47%; V5, 56.62%; mean, 35.21%) and spinal cord (maximum dose, 37.53%). Conclusion: Treatment replanning can account for anatomical changes during RT and thereby enable better normal tissue sparing, while allowing radical target doses with the possibility of maximizing local control. Advances in knowledge: This study supports the sparse dosimetric data regarding the quantitative tumour volume reduction, re-emphasizing the need for adaptive replanning for minimizing normal tissue toxicity without compromising local control, and adds to the existing body of literature. PMID:24628269

  14. Dosimetric Analysis of Respiratory-Gated Radiotherapy for Hepatocellular Carcinoma

    SciTech Connect

    Xi Mian; Zhang Li; Liu Mengzhong; Deng Xiaowu; Huang Xiaoyan; Liu Hui

    2011-07-01

    The purpose of this study was to define individualized internal target volume (ITV) for hepatocellular carcinoma (HCC) using 4D computed tomography (4DCT), and to determine the geometric and dosimetric benefits of respiratory gating. Gross tumor volumes (GTVs) were contoured on 10 respiratory phases of 4DCT images for 12 patients with HCC. Three treatment plans were prepared using different planning target volumes (PTVs): (1) PTV{sub 3D}, derived from a single helical clinical target volume (CTV) plus conventional margins; (2) PTV{sub 10phases}, derived from ITV{sub 10phases}, which encompassed all 10 CTVs plus an isotropic margin of 0.8 cm; (3) PTV{sub gating}, derived from ITV{sub gating}, which encompassed three CTVs within gating-window at end-expiration plus an isotropic margin of 0.8 cm. The PTV{sub 3D} was the largest volume for all patients. The ITV-based plans and gating plans spared more normal tissues than 3D plans, especially the liver. Without increasing normal tissue complication probability of the 3D plans, the ITV-based plans allowed for increasing the calculated dose from 50.8 Gy to 54.7 Gy on average, and the gating plans could further escalate the dose to 58.5 Gy. Compared with ITV-based plans, the dosimetric gains with gating plan strongly correlated with GTV mobility in the craniocaudal direction. The ITV-based plans can ensure target coverage with less irradiation of normal tissues compared with 3D plans. Respiratory-gated radiotherapy can further reduce the target volumes to spare more surrounding tissues and allow dose escalation, especially for patients with tumor mobility >1 cm.

  15. SU-E-T-134: Dosimetric Implications From Organ Segmentation

    SciTech Connect

    Wu, Z; Turian, J; Chu, J

    2014-06-01

    Purpose: To evaluate the dosimetric implications resulting from organ segmentation performed by different clinical experts Methods: Twelve patients received SBRT treatment to thoracic region within the past year were selected for this study. Three physicians contoured a set of organs following RTOG guideline. DVHs of all contours were generated from the approved plans used for treatment, and were compared to those produced during planning. Most OARs were evaluated on their max dose, some, such as heart and chest wall, were also evaluated on metrics such as max dose to 4cc of volume, or 30Gy volume dose. Results: In general, there is a greater dosimetric difference between the RTOG contour sets and clinical contour sets than among the three RTOG contour sets themselves for each patient. For example, there was no difference in esophagus max dose between the RTOG contour sets for ten patients. However, they showed an average of 2.3% higher max dose than the clinical contour set, with a standard deviation of 6.6%. The proximal bronchial tree (PBT) showed a similar behavior. The average difference of PBT max dose for seven patients is 0% between the three RTOG contour sets, with standard deviation of 1%. They showed an average of 16.1% higher max dose than the clinical contour set, with a standard deviation of 126%. Conclusion: This study shows that using RTOG contouring standards improves segmentation consistency between different physicians; most of the contours examined showed less than 1% dose difference. When RTOG contour sets were compared to the clinical contour set, the differences are much more significant. Thus it is important to standardize contouring guidelines in radiation therapy treatment planning. This will reduce uncertainties in clinical outcome analysis and research studies.

  16. A revised dosimetric model of the head and brain

    SciTech Connect

    Bolch, W.E.; Poston, J.W. Sr.

    1995-05-01

    The use of PET and SPECT radiopharmaceuticals in brain imaging has greatly expanded over the past several years. Many of these agents localize within particular subregions of the brain, thus allowing for detailed physiologic and metabolic imaging. Dosimetric models to support these advances in nuclear medicine have been lacking. For example, the brain within the phantom of MIRD Pamphlet No. 5 Revised is modeled simply as a single ellipsoid of tissue with no differentiation of its internal structures. To address this need, the MIRD Committee established a Task Group in 1992 to construct a revised dosimetric model of the brain to include the following subregions: the cerebral cortex, the white matter, the cerebellum, the thalamus, the caudate nucleus, the lentiform nucleus (putamen and globus pallidus), the cerebral spinal fluid (within the subarachnoid space of the brain), the lateral ventricles, and the third ventricle. Estimates of both electron and photon absorbed fractions (AF) were subsequently calculated using the EGS4 radiation transport code. For most of the internal brain structures, electron AFs are shown to fall fellow unity for all regions within the energy range of {approximately}200 keV to 4 MeV. For example, AFs for the caudate nucleus as both a source and target region and estimated as 0.98, 0.84, 0.39 for 200-keV, 1-MeV, and 4-MeV electron sources, respectively. Corresponding AFs within the white matter as a source and target region are estimated as 1.0, 0.95, and 0.79 for these same electron energies. Revised S values were subsequently calculated for a variety of beta-particle and positron emitters used in brain imaging.

  17. Electronic and postal reminders for improving immunisation coverage in children: protocol for a systematic review and meta-analysis

    PubMed Central

    Chachou, Martel J; Mukinda, Fidele K; Motaze, Villyen; Wiysonge, Charles S

    2015-01-01

    Introduction Worldwide, suboptimal immunisation coverage causes the deaths of more than one million children under five from vaccine-preventable diseases every year. Reasons for suboptimal coverage are multifactorial, and a combination of interventions is needed to improve compliance with immunisation schedules. One intervention relies on reminders, where the health system prompts caregivers to attend immunisation appointments on time or re-engages caregivers who have defaulted on scheduled appointments. We undertake this systematic review to investigate the potential of reminders using emails, phone calls, social media, letters or postcards to improve immunisation coverage in children under five. Methods and analysis We will search for published and unpublished randomised controlled trials and non-randomised controlled trials in PubMed, Scopus, CINAHL, CENTRAL, Science Citation Index, WHOLIS, Clinicaltrials.gov and the WHO International Clinical Trials Platform. We will conduct screening of search results, study selection, data extraction and risk-of-bias assessment in duplicate, resolving disagreements by consensus. In addition, we will pool data from clinically homogeneous studies using random-effects meta-analysis; assess heterogeneity of effects using the χ2 test of homogeneity; and quantify any observed heterogeneity using the I2 statistic. Ethics and dissemination This protocol does not need approval by an ethics committee because we will use publicly available data, without directly involving human participants. The results will provide updated evidence on the effects of electronic and postal reminders on immunisation coverage, and we will discuss the applicability of the findings to low and middle-income countries. We plan to disseminate review findings through publication in a peer-reviewed journal and presentation at relevant conferences. In addition, we will prepare a policymaker-friendly summary using a validated format (eg, SUPPORT Summary) and

  18. Dosimetrically determined doses of radioiodine for the treatment of metastatic thyroid carcinoma.

    PubMed

    Van Nostrand, Douglas; Atkins, Frank; Yeganeh, Fred; Acio, Elmo; Bursaw, Randy; Wartofsky, Leonard

    2002-02-01

    In the absence of definitive studies relating radioiodine dose to outcomes, selection of a dose of radioiodine to treat metastatic thyroid carcinoma is problematic, and several approaches have been used. These include empiric fixed doses and doses used on dosimetric approaches specific for each patient. This paper is a review of the rationale and technique for dosimetrically-determined doses of radioiodine for the treatment of metastatic thyroid carcinoma. This review (1) discusses the alternatives for selection of a dose, (2) discusses the two major approaches for determining radioiodine doses dosimetrically, (3) briefly reviews several modifications of these approaches, (4) reviews the literature regarding the results, (5) discusses the side effects of these different approaches, and (6) concludes with recommendations for patient management and future research. This review does not address use of dosimetrically-determined doses of radioiodine for the initial ablation of thyroid tissue postoperatively.

  19. Effects of Dosimetrically Guided I-131 Therapy on Hematopoiesis in Patients With Differentiated Thyroid Cancer.

    PubMed

    Bikas, Athanasios; Schneider, Mark; Desale, Sameer; Atkins, Frank; Mete, Mihriye; Burman, Kenneth D; Wartofsky, Leonard; Van Nostrand, Douglas

    2016-04-01

    A retrospective analysis was performed to evaluate the effects of dosimetrically-guided I-131 treatment on hematopoiesis. Statistically significant decreases in CBC parameters following a specific time-pattern were shown.

  20. The investigation of prostatic calcifications using μ-PIXE analysis and their dosimetric effect in low dose rate brachytherapy treatments using Geant4.

    PubMed

    Pope, D J; Cutajar, D L; George, S P; Guatelli, S; Bucci, J A; Enari, K E; Miller, S; Siegele, R; Rosenfeld, A B

    2015-06-01

    Low dose rate brachytherapy is a widely used modality for the treatment of prostate cancer. Most clinical treatment planning systems currently in use approximate all tissue to water, neglecting the existence of inhomogeneities, such as calcifications. The presence of prostatic calcifications may perturb the dose due to the higher photoelectric effect cross section in comparison to water. This study quantitatively evaluates the effect of prostatic calcifications on the dosimetric outcome of brachytherapy treatments by means of Monte Carlo simulations and its potential clinical consequences.Four pathological calcification samples were characterised with micro-particle induced x-ray emission (μ-PIXE) to determine their heavy elemental composition. Calcium, phosphorus and zinc were found to be the predominant heavy elements in the calcification composition. Four clinical patient brachytherapy treatments were modelled using Geant4 based Monte Carlo simulations, in terms of the distribution of brachytherapy seeds and calcifications in the prostate. Dose reductions were observed to be up to 30% locally to the calcification boundary, calcification size dependent. Single large calcifications and closely placed calculi caused local dose reductions of between 30-60%. Individual calculi smaller than 0.5 mm in diameter showed minimal dosimetric impact, however, the effects of small or diffuse calcifications within the prostatic tissue could not be determined using the methods employed in the study. The simulation study showed a varying reduction on common dosimetric parameters. D90 showed a reduction of 2-5%, regardless of calcification surface area and volume. The parameters V100, V150 and V200 were also reduced by as much as 3% and on average by 1%. These reductions were also found to relate to the surface area and volume of calcifications, which may have a significant dosimetric impact on brachytherapy treatment, however, such impacts depend strongly on specific factors

  1. A dosimetric uncertainty analysis for photon-emitting brachytherapy sources: report of AAPM Task Group No. 138 and GEC-ESTRO.

    PubMed

    DeWerd, Larry A; Ibbott, Geoffrey S; Meigooni, Ali S; Mitch, Michael G; Rivard, Mark J; Stump, Kurt E; Thomadsen, Bruce R; Venselaar, Jack L M

    2011-02-01

    This report addresses uncertainties pertaining to brachytherapy single-source dosimetry preceding clinical use. The International Organization for Standardization (ISO) Guide to the Expression of Uncertainty in Measurement (GUM) and the National Institute of Standards and Technology (NIST) Technical Note 1297 are taken as reference standards for uncertainty formalism. Uncertainties in using detectors to measure or utilizing Monte Carlo methods to estimate brachytherapy dose distributions are provided with discussion of the components intrinsic to the overall dosimetric assessment. Uncertainties provided are based on published observations and cited when available. The uncertainty propagation from the primary calibration standard through transfer to the clinic for air-kerma strength is covered first. Uncertainties in each of the brachytherapy dosimetry parameters of the TG-43 formalism are then explored, ending with transfer to the clinic and recommended approaches. Dosimetric uncertainties during treatment delivery are considered briefly but are not included in the detailed analysis. For low- and high-energy brachytherapy sources of low dose rate and high dose rate, a combined dosimetric uncertainty <5% (k=1) is estimated, which is consistent with prior literature estimates. Recommendations are provided for clinical medical physicists, dosimetry investigators, and source and treatment planning system manufacturers. These recommendations include the use of the GUM and NIST reports, a requirement of constancy of manufacturer source design, dosimetry investigator guidelines, provision of the lowest uncertainty for patient treatment dosimetry, and the establishment of an action level based on dosimetric uncertainty. These recommendations reflect the guidance of the American Association of Physicists in Medicine (AAPM) and the Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) for their members and may also be used as

  2. A dosimetric uncertainty analysis for photon-emitting brachytherapy sources: report of AAPM Task Group No. 138 and GEC-ESTRO.

    PubMed

    DeWerd, Larry A; Ibbott, Geoffrey S; Meigooni, Ali S; Mitch, Michael G; Rivard, Mark J; Stump, Kurt E; Thomadsen, Bruce R; Venselaar, Jack L M

    2011-02-01

    This report addresses uncertainties pertaining to brachytherapy single-source dosimetry preceding clinical use. The International Organization for Standardization (ISO) Guide to the Expression of Uncertainty in Measurement (GUM) and the National Institute of Standards and Technology (NIST) Technical Note 1297 are taken as reference standards for uncertainty formalism. Uncertainties in using detectors to measure or utilizing Monte Carlo methods to estimate brachytherapy dose distributions are provided with discussion of the components intrinsic to the overall dosimetric assessment. Uncertainties provided are based on published observations and cited when available. The uncertainty propagation from the primary calibration standard through transfer to the clinic for air-kerma strength is covered first. Uncertainties in each of the brachytherapy dosimetry parameters of the TG-43 formalism are then explored, ending with transfer to the clinic and recommended approaches. Dosimetric uncertainties during treatment delivery are considered briefly but are not included in the detailed analysis. For low- and high-energy brachytherapy sources of low dose rate and high dose rate, a combined dosimetric uncertainty <5% (k=1) is estimated, which is consistent with prior literature estimates. Recommendations are provided for clinical medical physicists, dosimetry investigators, and source and treatment planning system manufacturers. These recommendations include the use of the GUM and NIST reports, a requirement of constancy of manufacturer source design, dosimetry investigator guidelines, provision of the lowest uncertainty for patient treatment dosimetry, and the establishment of an action level based on dosimetric uncertainty. These recommendations reflect the guidance of the American Association of Physicists in Medicine (AAPM) and the Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) for their members and may also be used as

  3. A dosimetric uncertainty analysis for photon-emitting brachytherapy sources: Report of AAPM Task Group No. 138 and GEC-ESTRO

    PubMed Central

    DeWerd, Larry A.; Ibbott, Geoffrey S.; Meigooni, Ali S.; Mitch, Michael G.; Rivard, Mark J.; Stump, Kurt E.; Thomadsen, Bruce R.; Venselaar, Jack L. M.

    2011-01-01

    This report addresses uncertainties pertaining to brachytherapy single-source dosimetry preceding clinical use. The International Organization for Standardization (ISO) Guide to the Expression of Uncertainty in Measurement (GUM) and the National Institute of Standards and Technology (NIST) Technical Note 1297 are taken as reference standards for uncertainty formalism. Uncertainties in using detectors to measure or utilizing Monte Carlo methods to estimate brachytherapy dose distributions are provided with discussion of the components intrinsic to the overall dosimetric assessment. Uncertainties provided are based on published observations and cited when available. The uncertainty propagation from the primary calibration standard through transfer to the clinic for air-kerma strength is covered first. Uncertainties in each of the brachytherapy dosimetry parameters of the TG-43 formalism are then explored, ending with transfer to the clinic and recommended approaches. Dosimetric uncertainties during treatment delivery are considered briefly but are not included in the detailed analysis. For low- and high-energy brachytherapy sources of low dose rate and high dose rate, a combined dosimetric uncertainty <5% (k=1) is estimated, which is consistent with prior literature estimates. Recommendations are provided for clinical medical physicists, dosimetry investigators, and source and treatment planning system manufacturers. These recommendations include the use of the GUM and NIST reports, a requirement of constancy of manufacturer source design, dosimetry investigator guidelines, provision of the lowest uncertainty for patient treatment dosimetry, and the establishment of an action level based on dosimetric uncertainty. These recommendations reflect the guidance of the American Association of Physicists in Medicine (AAPM) and the Groupe Européen de Curiethérapie–European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) for their members and may also be used

  4. A breathing thorax phantom with independently programmable 6D tumour motion for dosimetric measurements in radiation therapy

    NASA Astrophysics Data System (ADS)

    Steidl, P.; Richter, D.; Schuy, C.; Schubert, E.; Haberer, Th; Durante, M.; Bert, C.

    2012-04-01

    Irradiation of moving targets using a scanned ion beam can cause clinically intolerable under- and overdosages within the target volume due to the interplay effect. Several motion mitigation techniques such as gating, beam tracking and rescanning are currently investigated to overcome this restriction. To enable detailed experimental studies of potential mitigation techniques a complex thorax phantom was developed. The phantom consists of an artificial thorax with ribs to introduce density changes. The contraction of the thorax can be controlled by a stepping motor. A robotic driven detector head positioned inside the thorax mimics e.g. a lung tumour. The detector head comprises 20 ionization chambers and 5 radiographic films for target dose measurements. The phantom’s breathing as well as the 6D tumour motion (3D translation, 3D rotation) can be programmed independently and adjusted online. This flexibility allows studying the dosimetric effects of correlation mismatches between internal and external motions, irregular breathing, or baseline drifts to name a few. Commercial motion detection systems, e.g. VisionRT or Anzai belt, can be mounted as they would be mounted in a patient case. They are used to control the 4D treatment delivery and to generate data for 4D dose calculation. To evaluate the phantom’s properties, measurements addressing reproducibility, stability, temporal behaviour and performance of dedicated breathing manoeuvres were performed. In addition, initial dosimetric tests for treatment with a scanned carbon beam are reported.

  5. Dosimetric impact of applicator displacement during high dose rate (HDR) Cobalt-60 brachytherapy for cervical cancer: A planning study

    NASA Astrophysics Data System (ADS)

    Yong, J. S.; Ung, N. M.; Jamalludin, Z.; Malik, R. A.; Wong, J. H. D.; Liew, Y. M.; Ng, K. H.

    2016-02-01

    We investigated the dosimetric impact of applicator displacement on dose specification during high dose rate (HDR) Cobalt-60 (Co-60) brachytherapy for cervical cancer through a planning study. Eighteen randomly selected HDR full insertion plans were restrospectively studied. The tandem and ovoids were virtually shifted translationally and rotationally in the x-, y- and z-axis directions on the treatment planning system. Doses to reference points and volumes of interest in the plans with shifted applicators were compared with the original plans. The impact of dose displacement on 2D (point-based) and 3D (volume-based) treatment planning techniques was also assessed. A ±2 mm translational y-axis applicator shift and ±4° rotational x-axis applicator shift resulted in dosimetric changes of more than 5% to organs at risk (OAR) reference points. Changes to the maximum doses to 2 cc of the organ (D2cc) in 3D planning were statistically significant and higher than the reference points in 2D planning for both the rectum and bladder (p<0.05). Rectal D2cc was observed to be the most sensitive to applicator displacement among all dose metrics. Applicator displacement that is greater than ±2 mm translational y-axis and ±4° rotational x-axis resulted in significant dose changes to the OAR. Thus, steps must be taken to minimize the possibility of applicator displacement during brachytherapy.

  6. Dosimetric feasibility of real-time MRI-guided proton therapy

    SciTech Connect

    Moteabbed, M. Schuemann, J.; Paganetti, H.

    2014-11-01

    Purpose: Magnetic resonance imaging (MRI) is a prime candidate for image-guided radiotherapy. This study was designed to assess the feasibility of real-time MRI-guided proton therapy by quantifying the dosimetric effects induced by the magnetic field in patients’ plans and identifying the associated clinical consequences. Methods: Monte Carlo dose calculation was performed for nine patients of various treatment sites (lung, liver, prostate, brain, skull-base, and spine) and tissue homogeneities, in the presence of 0.5 and 1.5 T magnetic fields. Dose volume histogram (DVH) parameters such as D{sub 95}, D{sub 5}, and V{sub 20} as well as equivalent uniform dose were compared for the target and organs at risk, before and after applying the magnetic field. The authors further assessed whether the plans affected by clinically relevant dose distortions could be corrected independent of the planning system. Results: By comparing the resulting dose distributions and analyzing the respective DVHs, it was determined that despite the observed lateral beam deflection, for magnetic fields of up to 0.5 T, neither was the target coverage jeopardized nor was the dose to the nearby organs increased in all cases except for prostate. However, for a 1.5 T magnetic field, the dose distortions were more pronounced and of clinical concern in all cases except for spine. In such circumstances, the target was severely underdosed, as indicated by a decrease in D{sub 95} of up to 41% of the prescribed dose compared to the nominal situation (no magnetic field). Sites such as liver and spine were less affected due to higher tissue homogeneity, typically smaller beam range, and the choice of beam directions. Simulations revealed that small modifications to certain plan parameters such as beam isocenter (up to 19 mm) and gantry angle (up to 10°) are sufficient to compensate for the magnetic field-induced dose disturbances. The authors’ observations indicate that the degree of required

  7. Dosimetric feasibility of real-time MRI-guided proton therapy

    PubMed Central

    Moteabbed, M.; Schuemann, J.; Paganetti, H.

    2014-01-01

    Purpose: Magnetic resonance imaging (MRI) is a prime candidate for image-guided radiotherapy. This study was designed to assess the feasibility of real-time MRI-guided proton therapy by quantifying the dosimetric effects induced by the magnetic field in patients’ plans and identifying the associated clinical consequences. Methods: Monte Carlo dose calculation was performed for nine patients of various treatment sites (lung, liver, prostate, brain, skull-base, and spine) and tissue homogeneities, in the presence of 0.5 and 1.5 T magnetic fields. Dose volume histogram (DVH) parameters such as D95, D5, and V20 as well as equivalent uniform dose were compared for the target and organs at risk, before and after applying the magnetic field. The authors further assessed whether the plans affected by clinically relevant dose distortions could be corrected independent of the planning system. Results: By comparing the resulting dose distributions and analyzing the respective DVHs, it was determined that despite the observed lateral beam deflection, for magnetic fields of up to 0.5 T, neither was the target coverage jeopardized nor was the dose to the nearby organs increased in all cases except for prostate. However, for a 1.5 T magnetic field, the dose distortions were more pronounced and of clinical concern in all cases except for spine. In such circumstances, the target was severely underdosed, as indicated by a decrease in D95 of up to 41% of the prescribed dose compared to the nominal situation (no magnetic field). Sites such as liver and spine were less affected due to higher tissue homogeneity, typically smaller beam range, and the choice of beam directions. Simulations revealed that small modifications to certain plan parameters such as beam isocenter (up to 19 mm) and gantry angle (up to 10°) are sufficient to compensate for the magnetic field-induced dose disturbances. The authors’ observations indicate that the degree of required corrections strongly depends

  8. To designate the facility of the United States Postal Service located at 200 South Morgan Street in Shelbyville, Illinois, as the "Jesse M. Donaldson Post Office".

    THOMAS, 112th Congress

    Rep. Shimkus, John [R-IL-19

    2011-05-03

    05/13/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  9. To designate the facility of the United States Postal Service located at 4110 Almeda Road in Houston, Texas, as the "George Thomas 'Mickey' Leland Post Office Building".

    THOMAS, 112th Congress

    Rep. Jackson Lee, Sheila [D-TX-18

    2011-01-05

    02/08/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  10. To designate the facility of the United States Postal Service located at 1900 West Gray Street in Houston, Texas, as the "Hazel Hainsworth Young Post Office Building".

    THOMAS, 112th Congress

    Rep. Jackson Lee, Sheila [D-TX-18

    2011-01-05

    02/08/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  11. To designate the facility of the United States Postal Service located at 2271 Lake Avenue in Altadena, California, as the "First Lieutenant Oliver Goodall Post Office".

    THOMAS, 112th Congress

    Rep. Schiff, Adam B. [D-CA-29

    2011-02-14

    02/18/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  12. To amend title 39, United States Code, to allow the United States Postal Service to provide nonpostal services, and for other purposes.

    THOMAS, 112th Congress

    Rep. Cohen, Steve [D-TN-9

    2011-09-23

    10/03/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  13. To designate the facility of the United States Postal Service located at 16300 Broadway Avenue in Maple Heights, Ohio, as the "Daniel Kondas Post Office".

    THOMAS, 112th Congress

    Rep. Fudge, Marcia L. [D-OH-11

    2011-05-02

    05/13/2011 Referred to the Subcommittee on Federal Workforce, U.S. Postal Service, and Labor Policy . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  14. Dosimetric evaluations of the interplay effect in respiratory-gated intensity-modulated radiation therapy

    SciTech Connect

    Chen Hungcheng; Wu, Andrew; Brandner, Edward D.; Heron, Dwight E.; Huq, M. Saiful; Yue, Ning J.; Chen Wencheng

    2009-03-15

    The interplay between a mobile target and a dynamic multileaf collimator can compromise the accuracy of intensity-modulated radiation therapy (IMRT). Our goal in this study is to investigate the dosimetric effects caused by the respiratory motion during IMRT. A moving phantom was built to simulate the typical breathing motion. Different sizes of the gating windows were selected for gated deliveries. The residual motions during the beam-on period ranged from 0.5 to 3 cm. An IMRT plan with five treatment fields from different gantry angles were delivered to the moving phantom for three irradiation conditions: Stationary condition, moving with the use of gating system, and moving without the use of gating system. When the residual motion was 3 cm, the results showed significant differences in dose distributions between the stationary condition and the moving phantom without gating beam control. The overdosed or underdosed areas enclosed about 33% of the treatment area. In contrast, the dose distribution on the moving phantom with gating window set to 0.5 cm showed no significant differences from the stationary phantom. With the appropriate setting of the gating window, the deviation of dose from the respiratory motion can be minimized. It appeals that limiting the residual motion to less than 0.5 cm is critical for the treatments of mobile structures.

  15. Angiostrongylus vasorum in Great Britain: a nationwide postal questionnaire survey of veterinary practices.

    PubMed

    Kirk, L; Limon, G; Guitian, F J; Hermosilla, C; Fox, M T

    2014-08-01

    The lungworm, Angiostrongylus vasorum, was first reported in indigenous dogs in southwestern England in 1980 and has since been recorded in Wales, southeastern England and, more recently, in the West Midlands, northern England and Scotland. The nationwide distribution of the parasite was evaluated using a postal questionnaire sent to 3950 small animal practices during 2009. Information was sought on the location of each practice, awareness of the parasite locally, number of cases diagnosed over the past year and whether diagnosis was based on clinical signs alone or supported by additional tests. 1419 practices returned a usable response, the majority being located in a city/town. Nearly one-third of responding practices were aware of the parasite locally, 20.7 per cent had seen at least one confirmed case and 0.3 per cent >20 confirmed cases over the past year. The most widely used tests were faecal examination and any type of imaging. Existing clusters of infection were detected in southeastern England and south Wales; infection was also found to be widespread in central England, though patchy in northern England and Scotland. Using distribution of clinical cases as an indicator of parasite distribution, this study confirmed that A. vasorum has spread beyond traditional UK endemic foci.

  16. Public Health Investigation After the Discovery of Ricin in a South Carolina Postal Facility

    PubMed Central

    Schier, Joshua G.; Patel, Manish M.; Belson, Martin G.; Patel, Amee; Schwartz, Michael; Fitzpatrick, Nicole; Drociuk, Dan; Deitchman, Scott; Meyer, Richard; Litovitz, Toby; Watson, William A.; Rubin, Carol H.; Kiefer, Max

    2007-01-01

    Objectives. In October 2003, a package containing ricin and a note threatening to poison water supplies was discovered in a South Carolina postal facility, becoming the first potential chemical terrorism event involving ricin in the United States. We examined the comprehensive public health investigation that followed and discuss the lessons learned from it. Methods. An investigation consisting primarily of environmental sampling for ricin contamination, performance of health assessments on affected personnel, and local, regional, and national surveillance for ricin-associated illness. Results. Laboratory analysis of 75 environmental sampling specimens revealed no ricin contamination. Health assessments of 36 affected employees were completed. Local surveillance initially identified 3 suspected cases, and national surveillance identified 399 outliers during the 2-week period after the incident. No confirmed cases of ricin-associated illness were identified. Conclusions. A multifaceted and multidisciplinary approach is required for an effective public health response to a chemical threat such as ricin. The results of all of the described activities were used to determine that the facility was safe to reopen and that no public health threat existed. PMID:17413057

  17. The dosimetric impact of dental implants on head-and-neck volumetric modulated arc therapy

    NASA Astrophysics Data System (ADS)

    Lin, Mu-Han; Li, Jinsheng; Price, Robert A., Jr.; Wang, Lu; Lee, Chung-Chi; Ma, C.-M.

    2013-02-01

    This work aims to investigate the dosimetric impact of dental implants on volumetric modulated arc therapy (VMAT) for head-and-neck patients and to evaluate the effectiveness of using the material's electron-density ratio for the correction. An in-house Monte Carlo (MC) code was utilized for the dose calculation to account for the scattering and attenuation caused by the high-Z implant material. Three different dental implant materials were studied in this work: titanium, Degubond®4 and gold. The dose perturbations caused by the dental implant materials were first investigated in a water phantom with a 1 cm3 insert. The per cent depth dose distributions of a 3 × 3 cm2 photon field were compared with the insert material as water and the three selected dental implant materials. To evaluate the impact of the dental implant on VMAT patient dose calculation, four head-and-neck cases were selected. For each case, the VMAT plan was designed based on the artifact-corrected patient geometry using a treatment planning system (TPS) that was typically utilized for routine patient treatment. The plans were re-calculated using the MC code for five situations: uncorrected geometry, artifact-corrected geometry and artifact-corrected geometry with one of the three different implant materials. The isodose distributions and the dose-volume histograms were cross-compared with each other. To evaluate the effectiveness of using the material's electron-density ratio for dental implant correction, the implant region was set as water with the material's electron-density ratio and the calculated dose was compared with the MC simulation with the real material. The main effect of the dental implant was the severe attenuation in the downstream. The 1 cm3 dental implant can lower the downstream dose by 10% (Ti) to 51% (Au) for a 3 × 3 cm2 field. The TPS failed to account for the dose perturbation if the dental implant material was not precisely defined. For the VMAT patient dose calculation

  18. Dosimetric effects on small-field beam-modeling for stereotactic body radiation therapy

    NASA Astrophysics Data System (ADS)

    Cho, Woong; Kim, Suzy; Kim, Jung-In; Wu, Hong-Gyun; Jung, Joo-Young; Kim, Min-Joo; Suh, Tae-Suk; Kim, Jin-Young; Kim, Jong Won

    2015-02-01

    The treatment planning of stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) requires high accuracy of dosimetric data for small radiation fields. The dosimetric effects on the beam-modeling process of a treatment planning system (TPS) were investigated using different measured small-field data sets. We performed small-field dosimetry with three detectors: a CC13 ion chamber, a CC01 ion chamber, and an edge detector. Percentage depth doses (PDDs) and dose profiles for field sizes given by 3 × 3 cm2, 2 × 2 cm2, and 1 × 1 cm2 were obtained for 6 MV and 15 MV photon beams. Each measured data set was used as data input for a TPS, in which a beam-modeling process was implemented using the collapsed cone convolution (CCC) algorithm for dose calculation. The measured data were used to generate six beam-models based on each combination of detector type and photon energy, which were then used to calculate the corresponding PDDs and dose profiles for various depths and field sizes. Root mean square differences (RMSDs) between the calculated and the measured doses were evaluated for the PDDs and the dose profiles. The RMSDs of PDDs beyond the maximum dose depth were within an accuracy of 0.2-0.6%, being clinically acceptable. The RMSDs of the dose profiles corresponding to the CC13, the CC01, and the edge detector were 2.80%, 1.49%, and 1.46% for a beam energy of 6 MV and 2.34%, 1.15%, and 1.44% for a beam energy of 15 MV, respectively. The calculated results for the CC13 ion chamber showed the most discrepancy compared to the measured data, due to the relatively large sensitive volume of this detector. However, the calculated dose profiles for the detectors were not significantly different from another. The physical algorithm used in the beam-modeling process did not seem to be sensitive to blurred data measured with detectors with large sensitive volumes. Each beam-model was used to clinically evaluate lung and lymphatic node SBRT plans

  19. Dosimetric characterization of a microDiamond detector in clinical scanned carbon ion beams

    SciTech Connect

    Marinelli, Marco; Prestopino, G. Verona, C.; Verona-Rinati, G.; Ciocca, M.; Mirandola, A.; Mairani, A.; Raffaele, L.; Magro, G.

    2015-04-15

    Purpose: To investigate for the first time the dosimetric properties of a new commercial synthetic diamond detector (PTW microDiamond) in high-energy scanned clinical carbon ion beams generated by a synchrotron at the CNAO facility. Methods: The detector response was evaluated in a water phantom with actively scanned carbon ion beams ranging from 115 to 380 MeV/u (30–250 mm Bragg peak depth in water). Homogeneous square fields of 3 × 3 and 6 × 6 cm{sup 2} were used. Short- and medium-term (2 months) detector response stability, dependence on beam energy as well as ion type (carbon ions and protons), linearity with dose, and directional and dose-rate dependence were investigated. The depth dose curve of a 280 MeV/u carbon ion beam, scanned over a 3 × 3 cm{sup 2} area, was measured with the microDiamond detector and compared to that measured using a PTW Advanced Markus ionization chamber, and also simulated using FLUKA Monte Carlo code. The detector response in two spread-out-Bragg-peaks (SOBPs), respectively, centered at 9 and 21 cm depths in water and calculated using the treatment planning system (TPS) used at CNAO, was measured. Results: A negligible drift of detector sensitivity within the experimental session was seen, indicating that no detector preirradiation was needed. Short-term response reproducibility around 1% (1 standard deviation) was found. Only 2% maximum variation of microDiamond sensitivity was observed among all the evaluated proton and carbon ion beam energies. The detector response showed a good linear behavior. Detector sensitivity was found to be dose-rate independent, with a variation below 1.3% in the evaluated dose-rate range. A very good agreement between measured and simulated Bragg curves with both microDiamond and Advanced Markus chamber was found, showing a negligible LET dependence of the tested detector. A depth dose curve was also measured by positioning the microDiamond with its main axis oriented orthogonally to the beam

  20. An evaluation of a novel synthetic diamond probe for dosimetric applications

    NASA Astrophysics Data System (ADS)

    Ade, N.; Nam, T. L.

    2015-10-01

    A study is presented that characterises the dosimetric performances of two synthetic diamond sensors (HP1 and HP2) when either one or both detectors are subjected to clinical beams of various types under large as well as small-field conditions. Detector performances were evaluated using a prototype probe housing constructed of tissue-equivalent materials. The probe can accommodate diamond sensors of various sizes and is configured for radiation detection in different exposure orientations without having first to re-orient the sensor plate within its body. Also, the diamond sensor is aligned in the same configuration as its rectangular housing and the probe is designed to be compatible with commercially available electrometer systems. Dosimetric measurements were conducted using mammography X-rays (25-32 kVp) and megavoltage electron (6-21 MeV) and photon (60Co γ-ray, 6-18 MV X-ray) beams. Whereas HP1 was evaluated using all beam types under large-flied conditions and small-photon-beam fields down to 0.7×0.7 cm2, HP2 was evaluated using small-electron and photon-beam conditions down to 0.3×0.3 cm2 6 MV photon field. Using HP1 sensor, the synthetic diamond probe was found not to require daily pre-irradiation as long as it is properly shielded from ambient light and its response stabilised. Furthermore, the diamond probe exhibited linear response characteristics with absorbed dose and on exposure parameters to various beam types, negligible energy dependence and almost no variation in angular response. Exposing the sensor HP2 under a 0.4×0.4 cm2 6 MV photon radiation field, a sensitivity value of 197.3 nC Gy-1 mm-3 was established compared to a value of 136.1 nC Gy-1 mm-3 obtained with a small-field diode detector. Also, a figure of 5.5×103 for the SNR was established for the sensor in the same radiation field. Relative beam data measured with the diamond sensors were found to agree within 1-2% with data obtained with reference detectors. The presentation